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1.
Eur Rev Med Pharmacol Sci ; 21(1): 61-67, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-28121355

RESUMEN

OBJECTIVE: Bone metastasis is a common complication of prostate cancer. This study investigates serum bone sialoprotein (BSP), prostate specific antigen doubling time (PSADT), and extracellular matrix protein Spondin-2 levels in prostate cancer and the diagnostic significance of their ROC curves in bone metastasis. PATIENTS AND METHODS: A total of 85 cases of prostate cancer patients, including 43 cases with bone metastases and 42 cases without bone metastases, were enrolled. Serum BSP, Spondin-2, and PSA were tested by ELISA and Electrochemical Luminescence method. PSADT was calculated upon multiplication formula. The diagnostic significances of BSP, Spondin-2, and PSADT on bone metastasis were evaluated by ROC curve. RESULTS: Serum BSP, Spondin-2, and PSA levels were highest in prostate cancer with bone metastasis, followed by no bone metastasis, hyperplasia, and control (p < 0.05). Gleason scores of BSP, Spondin-2, and PSA were highest in low differentiation, followed by moderate differentiation and high differentiation (p < 0.05). ROC curve revealed that diagnostic efficiency was in PSADT, Spondin-2, and BSP in the order. Their sensitivity and specificity for the diagnosis of bone metastasis were 79.07, 88.37, 86.05%, and 71.54, 81.30, 83.74%, respectively. Their joint detection elevated the sensitivity to 97.67%, the negative predictive value up to 99.11%, and AUC to 0.973 (95% CI 0.942-0.998). PSADT + BSP exhibited better efficiency among two indicators combination as AUC reached 0.963 (95% CI 0.935-0.992). CONCLUSIONS: Serum BSP, Spondin-2, and PSADT upregulated in prostate cancer patients with bone metastasis. Their joint detection can improve the diagnostic sensitivity.


Asunto(s)
Neoplasias Óseas/secundario , Proteínas de la Matriz Extracelular/sangre , Sialoproteína de Unión a Integrina/sangre , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/patología , Neoplasias Óseas/sangre , Estudios de Casos y Controles , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Próstata/sangre , Curva ROC
2.
Epidemiol Infect ; 143(4): 704-10, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24945365

RESUMEN

We investigated a gastroenteritis outbreak in Erzurum city, Turkey in December 2012 to identify its cause and mode of transmission. We defined a probable case as onset of diarrhoea (⩾3 episodes/day) or vomiting, plus fever or nausea or abdominal pain during 19-27 December, 2012 in an Erzurum city resident. In a case-control study we compared exposures of 95 randomly selected probable cases and 95 neighbourhood-matched controls. We conducted bacterial culture and real-time multiplex PCR for identification of pathogens. During the week before illness onset, 72% of cases and 15% of controls only drank water from antique neighbourhood fountains; conversely, 16% of cases and 65% of controls only drank bottled or tap water (adjusted odds ratio 20, 95% confidence interval 4·6-84, after controlling for age and sex using conditional logistic regression). Of eight stool specimens collected, two were positive for Shigella sonnei, one for astrovirus, one for astrovirus and norovirus, and one for astrovirus and rotavirus. Water samples from the fountains had elevated total coliform (38-300/100 ml) and Escherichia coli (22-198/100 ml) counts. In conclusion, drinking contaminated fountain water caused this multi-pathogen outbreak. Residents should stop drinking water from these fountains, and clean water from the water treatment plant should be connected to the fountains.


Asunto(s)
Brotes de Enfermedades , Agua Potable/microbiología , Gastroenteritis/etiología , Microbiología del Agua , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Infecciones por Astroviridae/epidemiología , Infecciones por Astroviridae/etiología , Infecciones por Caliciviridae/epidemiología , Infecciones por Caliciviridae/etiología , Estudios de Casos y Controles , Niño , Preescolar , Coinfección/epidemiología , Coinfección/etiología , Coinfección/microbiología , Coinfección/virología , Agua Potable/virología , Disentería Bacilar/epidemiología , Disentería Bacilar/etiología , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/etiología , Femenino , Gastroenteritis/epidemiología , Gastroenteritis/microbiología , Gastroenteritis/virología , Humanos , Masculino , Mamastrovirus , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa Multiplex , Norovirus , Características de la Residencia , Rotavirus , Infecciones por Rotavirus/epidemiología , Infecciones por Rotavirus/etiología , Shigella sonnei , Turquía/epidemiología , Adulto Joven
3.
J Adv Dielectr ; 1(1): 85-89, 2011 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-21785672

RESUMEN

Novel PZT-5A ceramic-polymer composite was prepared via freezing technology. This composite exhibited good dielectric and ferroelectric behaviors. At 1 kHz, the dielectric constant and the dielectric loss were 546 and 0.046, respectively, while the remnant polarization was 13.0 µC/cm(2) at room temperature. The electromechanical coupling coefficient (k(t)) of PZT-5A composite was measured to be 0.54, which is similar to that of PZT piezoelectric ceramic. The piezoelectric coefficient (d(33)) of PZT-5A composite was determined to be ~250 pC/N. Using this composite, a 58MHz single element transducer with the bandwidth of 70% at -6dB was built, and the insertion loss was tested to be -29dB around the central frequency.

4.
Appl Phys Lett ; 94(10): 102901, 2009 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-19529788

RESUMEN

Using a simple rapid heating process, Pb(Zr(0.52)Ti(0.48))O(3) (PZT) thick films prepared by hydrothermal method were separated from a Ti substrate. Scanning electron microscopy (SEM) revealed that the self-separated films were crack-free. After solution infiltration and high temperature annealing, the PZT thick films were shown to possess good electric properties. At 1 kHz, the dielectric constant and the loss were 593 and 0.05, respectively. The remnant polarization was 30.0 muCcm(2) at room temperature. A high frequency single element ultrasound transducer fabricated with these films showed a bandwidth at -6 dB of 73% at a center frequency of 67 MHz.

5.
J Phys Condens Matter ; 20(27): 275230, 2008 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-21694391

RESUMEN

The structural properties associated with the orbitally induced Peierls transition in MgTi(2)O(4) are characterized by in situ cooling TEM observations. A distinctive structural modulation with the wavevector of q(1) = 1/4 (0, 0, 4) has been well demonstrated below a critical temperature of about 260 K for MgTi(2)O(4). Systematic analysis demonstrates that this structural modulation can be well explained by an orbital order existing in the low-temperature insulating phase. It is also noted that the nonstoichiometric feature commonly appearing in the present system could yield visible changes in both physical and structural properties. A low-temperature study of the microstructure of Mg[Ti(1.9)Mg(0.1)]O(4) reveals that a little substitution of Mg(2+) for Ti(3+) ions on the octahedral sites can disrupt the long-range order of the t(2g) orbitals, resulting in complex tweed structures in the superstructure phase.

6.
Nanotechnology ; 19(4): 045605, 2008 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-21817511

RESUMEN

A low-cost and catalyst-free two-step approach has been developed to produce ZnO nanotubes (ZNTs) by simple thermal oxidation of Zn nanowires under 20 Pa at a low temperature of 400 °C. The growth mechanism of ZNTs is discussed in detail. The formation of these tubular structures is closely linked to the oxidation pressure and temperature, which involves a process consisting of the deposition of Zn nanowires, cracking of the Zn nanowires and sublimation of the Zn cores, and subsequent oxidation to ZNTs. The optical properties were studied by using Raman and photoluminescence spectra, where a strong green emission related to the single ionized oxygen vacancy appears. The photocatalytic activity measurement indicates an enhanced photocatalytic activity of the prepared ZNTs due to their high surface-to-volume ratios and abundant oxygen vacancies near the surfaces of the ZNTs. This type of high surface area structural ZNTs could find promising potential for optoelectronic and environmental applications.

7.
J Phys D Appl Phys ; 42(2): nihpa129997, 2008 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-19668350

RESUMEN

In this paper, we report on 4.5µm piezoelectric Pb(Zr(0.52)Ti(0.48))O(3) (PZT) thick films deposited on flexible stainless steel (SS) foils with LaNiO(3) (LNO) buffer layers using a ceramic powder/sol-gel solution modified composite method. The polycrystalline thick films show a hysteresis loop at an applied electric field of 900 kV cm(-1) with remanent polarization and coercive electric field values of 27µC cm(-2) and 85 kV cm(-1), respectively. At 1 kHz, the dielectric constant is 653 and the dielectric loss is 0.052. The leakage current density of the film is lower than 1.55 × 10(-5) Acm(-2) over the range of 0 to ±150V. The conduction current shows ohmic behaviour at a low electric field and space-charge-limited current characteristics at a high electric field.

8.
Appl Phys A Mater Sci Process ; 2008: 161-163, 2008 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-20953269

RESUMEN

In this work, a novel high-frequency ultrasonic transducer structure is realized by using PMNPT-on-silicon technology and silicon micromachining. To prepare the single crystalline PMNPT-on-silicon wafers, a hybrid processing method involving wafer bonding, mechanical lapping and wet chemical thinning is successfully developed. In the transducer structure, the active element is fixed within the stainless steel needle housing. The measured center frequency and -6 dB bandwidth of the transducer are 35 MHz and 34%, respectively. Owing to the superior electromechanical coupling coefficient (k(t)) and high piezoelectric constant (d(33)) of PMNPT film, the transducer shows a good energy conversion performance with a very low insertion loss down to 8.3 dB at the center frequency.

9.
Int J Obes (Lond) ; 30(1): 164-70, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16231026

RESUMEN

BACKGROUND: Obesity interventions are implemented at state or sub-state level in the United States (US), where only self-reported weight and height data for adults are available from the Behavioral Risk Factor Surveillance System (BRFSS). The prevalence estimates of overweight and obesity generated from self-reported weight and height from BRFSS are known to underestimate the true prevalence. However, whether this underestimation is consistent across different demographic groups has not been fully investigated. METHODS: In this study, we compared the prevalence estimates of obesity (body mass index (BMI) > or =30 kg/m(2)) and overweight (BMI > or =25 kg/m(2)) in different demographic groups in the US from the National Health and Nutrition Examination Survey (NHANES) and BRFSS during 1999-2000. We also compared the rank orders of the obesity and overweight prevalence across different demographic groups from the two data sources. RESULTS: Compared to NHANES, BRFSS underestimated the overall prevalence of obesity and overweight by 9.5 and 5.7 percentage points, respectively. The underestimation differed across different demographic groups: the underestimation of obesity and overweight prevalence was higher among women (13.1 and 12.2 percentage points, respectively) than among men (5.8 and -0.6 percentage points, respectively). The variation of underestimation was higher among men. A clear inverse association between educational attainment and obesity prevalence among non-Hispanic African American women was observed from BRFSS data. However, no such association was found from NHANES. While BRFSS can identify correctly the population with the highest obesity and overweight burden, it did not accurately rank the obesity and overweight prevalence across different demographic groups. CONCLUSION: Compared to NHANES, BRFSS disproportionately underestimates the prevalence of obesity and overweight across different gender, race, age, and education subgroups.


Asunto(s)
Obesidad/epidemiología , Adulto , Negro o Afroamericano/estadística & datos numéricos , Distribución por Edad , Escolaridad , Métodos Epidemiológicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obesidad/etnología , Sobrepeso , Distribución por Sexo , Factores Socioeconómicos , Estados Unidos/epidemiología , Población Blanca/estadística & datos numéricos
10.
Int J Gynaecol Obstet ; 89 Suppl 1: S25-33, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15820365

RESUMEN

The relationship between interpregnancy interval and adverse birth outcomes (i.e., low birth weight, preterm birth, and small size for gestational age) was examined in three recent studies conducted in Utah and Michigan of the United States. These studies were conducted among different populations, used different study designs (i.e., cross-sectional and retrospective cohort designs), and addressed several other methodological limitations in the previously published literature. In addition, the data were stratified by, and controlled for, several maternal reproductive risk factors. A J-shaped relationship between interpregnancy interval and adverse birth outcomes was observed in all three studies. The risk for adverse birth outcomes is lowest when the interpregnancy interval was 18-23 months and increased when the interval departed from 18-23 months. This J-shaped relationship existed at levels of maternal reproductive risk factors and after these risk factors were controlled for using logistic regression. Based on the consistency of the findings from all three studies, it appears that the J-shaped relationship between interpregnancy interval and adverse birth outcomes is causal. This information can be used by health care providers and public health programs to counsel and educate women who recently gave births on reducing the risk for adverse birth outcomes by means of appropriate pregnancy spacing.


Asunto(s)
Intervalo entre Nacimientos , Resultado del Embarazo , Estudios Transversales , Femenino , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Recién Nacido Pequeño para la Edad Gestacional , Embarazo , Nacimiento Prematuro , Estudios Retrospectivos , Factores de Riesgo , Estados Unidos
11.
Am J Obstet Gynecol ; 185(6): 1403-10, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11744916

RESUMEN

OBJECTIVE: We evaluated interpregnancy interval in relation to adverse perinatal outcomes and whether the relationship differed by race. STUDY DESIGN: We analyzed the vital statistics data for multiparous white and black women in Michigan who delivered a singleton live birth during the period 1993 through 1998, using stratified and logistic regression techniques. RESULTS: Among women of both races, the risk for delivering low birth weight, premature, and small-for-gestational-age birth was lowest if the interpregnancy interval was 18 to 23 months. In comparison, among white women, the odds ratios for the 3 outcomes were 1.5, 1.3, and 1.3, respectively, if the interval was <6 months, and 1.9, 1.4, and 1.7, respectively, if the interval was > or =120 months, controlling for other factors. Similarly, among black women, the odds ratios were 1.5, 1.2, and 1.3, respectively, if the interval was <6 months, and 1.6, 1.3, and 1.4, respectively, if the interval was > or =120 months. CONCLUSION: An interpregnancy interval of 18 to 23 months is associated with the lowest risk for adverse perinatal outcomes among both white and black women.


Asunto(s)
Intervalo entre Nacimientos , Negro o Afroamericano , Resultado del Embarazo , Población Blanca , Femenino , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Recien Nacido Prematuro , Recién Nacido Pequeño para la Edad Gestacional , Oportunidad Relativa , Embarazo , Factores de Riesgo , Factores de Tiempo
12.
N Engl J Med ; 340(8): 589-94, 1999 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-10029642

RESUMEN

BACKGROUND: A short interval between pregnancies has been associated with adverse perinatal outcomes. Whether that association is due to confounding by other risk factors, such as maternal age, socioeconomic status, and reproductive history, is unknown. METHODS: We evaluated the interpregnancy interval in relation to low birth weight, preterm birth, and small size for gestational age by analyzing data from the birth certificates of 173,205 singleton infants born alive to multiparous mothers in Utah from 1989 to 1996. RESULTS: Infants conceived 18 to 23 months after a previous live birth had the lowest risks of adverse perinatal outcomes; shorter and longer interpregnancy intervals were associated with higher risks. These associations persisted when the data were stratified according to and controlled for 16 biologic, sociodemographic, and behavioral risk factors. As compared with infants conceived 18 to 23 months after a live birth, infants conceived less than 6 months after a live birth had odds ratios of 1.4 (95 percent confidence interval, 1.3 to 1.6) for low birth weight, 1.4 (95 percent confidence interval, 1.3 to 1.5) for preterm birth, and 1.3 (95 percent confidence interval, 1.2 to 1.4) for small size for gestational age; infants conceived 120 months or more after a live birth had odds ratios of 2.0 (95 percent confidence interval, 1.7 to 2.4);1.5 (95 percent confidence interval, 1.3 to 1.7), and 1.8 (95 percent confidence interval, 1.6 to 2.0) for these three adverse outcomes, respectively, when we controlled for all 16 risk factors with logistic regression. CONCLUSIONS: The optimal interpregnancy interval for preventing adverse perinatal outcomes is 18 to 23 months.


Asunto(s)
Intervalo entre Nacimientos , Resultado del Embarazo/epidemiología , Adolescente , Adulto , Certificado de Nacimiento , Factores de Confusión Epidemiológicos , Femenino , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Recien Nacido Prematuro , Recién Nacido Pequeño para la Edad Gestacional , Modelos Logísticos , Edad Materna , Oportunidad Relativa , Embarazo , Factores de Riesgo , Utah/epidemiología
13.
Am J Public Health ; 86(11): 1582-9, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8916524

RESUMEN

OBJECTIVE: This study sought to reassess the relationship between cigarette smoking and education. METHODS: Data from the 1983 to 1991 National Health Interview Survey for participants aged 25 years and older were used to plot the prevalence of current smoking, ever smoking, heavy smoking, and smoking cessation, as well as the adjusted log odds ratios, by years of education. RESULTS: The "less than high school graduate" category consisted of two groups with distinct smoking patterns: persons with 0 to 8 years and persons with 9 to 11 years of education. The latter were the most likely to be current, ever, and heavy smokers and the least likely to have quit smoking, whereas the former were similar to persons having 12 years of education. After 11 years of education, the likelihood of smoking decreased and that of smoking cessation increased with each successive year of education. These results persisted after the statistical adjustment for age, sex, ethnicity, poverty status, employment status, marital status, geographic region, and year of survey. CONCLUSIONS: The relationship between smoking and education is not monotonic. Thus, when evaluating smoking in relation to education, researchers should categorize years of education as follows: 0 to 8, 9 to 11, 12, 13 to 15, and 16 or more years.


Asunto(s)
Escolaridad , Fumar , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Prevalencia , Factores de Riesgo , Fumar/etnología , Cese del Hábito de Fumar , Estados Unidos
15.
Am J Public Health ; 86(3): 368-75, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8604762

RESUMEN

OBJECTIVES: This study investigated patterns of and risk factors for smoking among elementary school children in Beijing, China. METHODS: In 1988, anonymous questionnaires were administered to a multistage stratified cluster sample of 16996 students, aged mostly 10 to 12, in 479 fourth- to sixth-grade classes from 122 Beijing elementary schools. RESULTS: Approximately 28% of boys and 3% of girls had smoked cigarettes. The most frequently cited reasons for smoking initiation were "to imitate others' behavior" and "to see what it was like." Girls were more likely to get cigarettes from home than to purchase their own. Having close friends who smoked and being encouraged by close friends to smoke were strong risk factors for smoking. Smoking was also associated with lower parental socioeconomic status; having parents, siblings, or teachers who smoked; buying cigarettes for parents; performing poorly in school; and not believing that smoking is harmful to health. CONCLUSIONS: Gender differences in smoking prevalence among adolescents in China are larger than those among US teenagers, whereas the proximal risk factors for smoking are similar. Major efforts are needed to monitor and prevent smoking initiation among Chinese adolescents, particularly girls.


Asunto(s)
Fumar/epidemiología , Estudiantes , Adolescente , Niño , China/epidemiología , Análisis por Conglomerados , Femenino , Conocimientos, Actitudes y Práctica en Salud , Encuestas Epidemiológicas , Humanos , Modelos Logísticos , Masculino , Prevalencia , Factores de Riesgo , Fumar/psicología , Factores Socioeconómicos , Estudiantes/psicología , Encuestas y Cuestionarios
16.
Crit Care Med ; 24(1): 57-63, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8565539

RESUMEN

OBJECTIVES: To examine the impact of hospital mortality and intensive care unit (ICU) size on the performance of the Mortality Probability Model II system for use in quality assessment, and to examine the ability of model customization to produce accurate estimates of hospital mortality to characterize patients by severity of illness for clinical trials. DESIGN: Prospective evaluation of model performance, using retrospective data. SETTING: Data for the simulation were assembled from six adult medical and surgical ICUs in Massachusetts and New York. PATIENTS: Consecutive admissions (n = 4,224) to the Massachusetts and New York ICUs were studied. The mortality rate in the database was 18.7%. INTERVENTIONS: A computer simulation of several different hospital mortality rates and ICU sample sizes, using a multicenter database of consecutive ICU admissions, was utilized. We simulated 20 different mortality rates by randomly changing the outcomes at hospital discharge from "survived" to "deceased" and from "deceased" to "survived". Four sample size simulations used 75%, 50%, 25%, and 10% of the database. Ten replications of each mortality rate and samples size were constructed, and model calibration and discrimination were assessed for each replication. Model coefficients were customized, using logistic regression. MEASUREMENTS AND MAIN RESULTS: Vital status at hospital discharge was the outcome measure among the ICU patient population. Model performance was assessed using the Hosmer-Lemeshow C statistic for calibration, and the area under the receiver operating characteristic curve for discrimination. Goodness-of-fit tests and receiver operating characteristic curve areas demonstrated that the models were sensitive to differences in hospital mortality, indicating that they are useful quality assurance tools. Goodness-of-fit tests were more sensitive than the receiver operating characteristic curve areas. The further the hospital mortality rate diverged from the original rate, the worse the performance of the model. Sample size had an impact on these results. The smaller the sample size, the less likely the model was to perform poorly. Model coefficients were successfully customized to demonstrate that improved model performance can be achieved when necessary for clinical trial stratification. CONCLUSION: Mortality Probability Model II models can be used to assess quality of care in ICUs, but the size of the sample should be considered when assessing calibration and discrimination.


Asunto(s)
Simulación por Computador , Mortalidad Hospitalaria , Unidades de Cuidados Intensivos/estadística & datos numéricos , Modelos Estadísticos , Evaluación de Resultado en la Atención de Salud , Adulto , Investigación sobre Servicios de Salud/métodos , Humanos , Unidades de Cuidados Intensivos/normas , Modelos Logísticos , Garantía de la Calidad de Atención de Salud , Curva ROC , Tamaño de la Muestra , Índice de Severidad de la Enfermedad , Estados Unidos
18.
MMWR CDC Surveill Summ ; 43(3): 1-43, 1994 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-7969014

RESUMEN

PROBLEM/CONDITION: Surveillance of tobacco use is an essential component of any tobacco-control program. The information gathered can be used to guide research initiatives, intervention programs, and policy decisions. REPORTING PERIODS: This report covers the period 1900-1994 for per capita cigarette consumption; 1965-1991 for trends in cigarette smoking prevalence and cessation; 1974-1991 for trends in the number of cigarettes smoked daily by current smokers; 1987-1991 for recent patterns of tobacco use; 1970, 1987, and 1991 for trends in cigar/pipe smoking and snuff/chewing tobacco use; 1984-1992 for trends in state-specific prevalences of regular cigarette smoking; 1987-1992 for state-specific estimates of smokeless-tobacco use; and 1976-1993 for trends in cigarette smoking among U.S. high school seniors. DESCRIPTION OF SYSTEMS: Estimates of cigarette consumption are reported by the U.S. Department of Agriculture, which uses data from the U.S. Department of the Treasury, the U.S. Department of Commerce, the Tobacco Institute, and other sources. The National Health Interview Survey uses household interviews to provide nationally representative estimates (for the civilian, noninstitutionalized population) of cigarette smoking and other behaviors related to tobacco use. The Behavioral Risk Factor surveillance System uses telephone surveys of civilian, noninstitutionalized adults (> or = 18 years of age) to provide state-specific estimates of current cigarette smoking and use of smokeless tobacco. The University of Michigan's Institute for Social Research uses school-based, self-administered questionnaires to gather data on cigarette smoking from a representative sample of U.S. high school seniors. RESULTS: During the period 1900-1963, per capita cigarette consumption increased; after 1964, consumption declined. During the years 1965-1991, current cigarette smoking prevalence among persons ages > or = 18 years declined overall and in every sociodemographic category examined. Decrease in current smoking prevalence was slow in some groups (e.g., among persons with fewer years of formal education). Both the prevalence of never smoking and the prevalence of cessation increased from 1965 through 1991. The prevalence of current cigarette smoking, any tobacco smoking, and any tobacco use was highest among American Indians/Alaska Natives and non-Hispanic blacks and lowest among Asians/Pacific Islanders. The prevalence of cigar smoking and pipe smoking has declined substantially since 1970. The prevalence of smokeless-tobacco use among white males ages 18-34 years was higher in 1987 and 1991 than in 1970; among persons > or = 45 years of age, the use of smokeless tobacco was more common among blacks than whites in 1970 and 1987. Cigarette smoking prevalence has decreased in most states. The prevalence of smokeless tobacco use was especially high among men in West Virginia, Montana, and several southern states. From 1984-1993, prevalence of cigarette smoking remained constant among U.S. high school seniors. However, prevalence increased slightly for male seniors and white seniors, decreased slightly for female high school seniors, and decreased sharply for black high school seniors. INTERPRETATION: With the exceptions of increases in cigarette smoking among white and male high school seniors and in the use of smokeless tobacco among white males ages 18-34 years, reductions in tobacco use occurred in every subgroup examined. This decrease must continue if the national health objectives for the year 2000 are to be reached. ACTIONS TAKEN: Surveillance of tobacco use is ongoing. Effective interventions that discourage initiation and encourage cessation are being disseminated throughout the United States.


Asunto(s)
Plantas Tóxicas , Cese del Hábito de Fumar/estadística & datos numéricos , Fumar/epidemiología , Tabaco sin Humo , Adolescente , Adulto , Anciano , Recolección de Datos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Vigilancia de la Población , Prevalencia , Fumar/tendencias , Tabaquismo/epidemiología , Estados Unidos/epidemiología
19.
Int J Vitam Nutr Res ; 63(1): 11-6, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8320052

RESUMEN

We performed a double blind randomized study in order to assess the efficacy of a multivitamin supplement for the prevention of common infections in healthy elderly subjects. Non-institutionalized, independent subjects over 60 years of age, living in the Nevers area (central France) were recruited by announcements and randomly assigned to a treatment or a placebo group. The treatment or placebo tablets were to be taken daily for 4 months. The principal criterion of response was the incidence of infections, as recorded from a detailed questionnaire presented at entrance, in the middle (2 months) and at the end (4 months) of the study. Blood samples were taken at the entrance in the study and after two and four months in order to monitor vitamin status. No significant difference was found between the two groups for the incidence of infections. In fact the observed incidences during the two two-month periods were higher in the treatment (0.38 and 0.21) than in the placebo group (0.29 and 0.13). After two months and after four months of supplementation, blood vitamin indicators of the subjects were significantly higher in the treatment than in the placebo group for vitamins B1, B2, B6, E and folates (p < 0.001). The improvement of the vitamin C status was slightly higher in the treatment than in the placebo group. For vitamin A status, the evolution was similar in the two groups. In conclusion, short-term supplementation of healthy elderly subjects with the investigated supplement is not likely to afford a meaningful protection against common infections.


Asunto(s)
Control de Enfermedades Transmisibles/métodos , Vitaminas/uso terapéutico , Anciano , Método Doble Ciego , Femenino , Francia/epidemiología , Humanos , Infecciones/epidemiología , Masculino , Persona de Mediana Edad
20.
Int J Epidemiol ; 21(5): 854-61, 1992 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1468845

RESUMEN

Prevalence, behavioural patterns and risk factors of cigarette smoking were studied in a sample of 8437 junior high school students in Beijing in 1988. Smoking at least occasionally was reported by 34.4% of boys and 3.9% of girls, though the intensity tended to be low. Smoking prevalence increased with age among boys. Inhaling smoke into the lungs was practised by 68.2% of the boys who smoked and 37.3% of the girls. 'Believing that one looks elegant when smoking', 'trying to be fashionable' and 'seeking stimulation' were the most important reasons for smoking. Of the boys 83.5% and of the girls 86.5% usually smoked with friends or schoolmates. Many more boys (19.2%) than girls (1.7%) smoked at home. Examinations of risk factors for teenage smoking showed that it was associated with a combination of familial, psychological and socio-school factors, with peer group pressure being the most important one.


Asunto(s)
Conducta del Adolescente , Fumar/epidemiología , Adolescente , China/epidemiología , Femenino , Humanos , Masculino , Grupo Paritario , Prevalencia , Distribución Aleatoria , Factores de Riesgo
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