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1.
J Fish Biol ; 82(5): 1484-96, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23639149

RESUMO

Early-stage Chinook salmon Oncorhynchus tshawytscha embryos were incubated in artificial redds that mimicked hyporheic conditions in gravel-augmented habitat to assess survivorship. Two complementary experiments were conducted where units varied along gradients of (1) increasing interstitial flow velocity (0·05-2·50 cm s⁻¹) in a uniformly coarse (particles ≥22 mm) sediment mixture and (2) increasing sediment porosity with interstitial flow velocity held constant. Embryonic survivorship increased moderately along a gradient of interstitial flow velocity, while survivorship among units with varying sediment porosities was consistent. No evidence for flow-induced agitation and mortality was observed. Results suggest that high interstitial flow velocities may confer a moderate advantage for incubating salmonid embryos when conditions that typically reduce embryonic mortality (i.e. low concentrations of fine particles) are ideal.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Rios , Salmão/embriologia , Salmão/fisiologia , Animais
2.
Int J Obes (Lond) ; 37(3): 448-54, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22546778

RESUMO

BACKGROUND: Obesity prevalence stabilized in the US in the first decade of the 2000s. However, obesity prevalence may resume increasing if younger generations are more sensitive to the obesogenic environment than older generations. METHODS: We estimated cohort effects for obesity prevalence among young adults born in the 1980s. Using data collected from the National Health and Nutrition Examination Survey between 1971 and 2008, we calculated obesity for respondents aged between 2 and 74 years. We used the median polish approach to estimate smoothed age and period trends; residual non-linear deviations from age and period trends were regressed on cohort indicator variables to estimate birth cohort effects. RESULTS: After taking into account age effects and ubiquitous secular changes, cohorts born in the 1980s had increased propensity to obesity versus those born in the late 1960s. The cohort effects were 1.18 (95% CI: 1.01, 1.07) and 1.21 (95% CI: 1.02, 1.09) for the 1979-1983 and 1984-1988 birth cohorts, respectively. The effects were especially pronounced in Black males and females but appeared absent in White males. CONCLUSIONS: Our results indicate a generational divergence of obesity prevalence. Even if age-specific obesity prevalence stabilizes in those born before the 1980s, age-specific prevalence may continue to rise in the 1980s cohorts, culminating in record-high obesity prevalence as this generation enters its ages of peak obesity prevalence.


Assuntos
Obesidade/epidemiologia , Saúde Pública/estatística & dados numéricos , Adolescente , Adulto , Distribuição por Idade , Idoso , Índice de Massa Corporal , Criança , Pré-Escolar , Efeito de Coortes , Suscetibilidade a Doenças , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Obesidade/prevenção & controle , Prevalência , Saúde Pública/tendências , Fatores de Risco , Estados Unidos/epidemiologia
3.
Int J Obes (Lond) ; 37(8): 1129-34, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23229734

RESUMO

BACKGROUND: Abdominal obesity predicts a wide range of adverse health outcomes. Over the past several decades, prevalence of abdominal obesity has increased markedly in industrialized countries like the United States No previous analyses, however, have evaluated whether there are birth cohort effects for abdominal obesity. Estimating cohort effects is necessary to forecast future health trends and understand the past population-level trends. METHODS: This analysis evaluated whether there were birth cohort effects for abdominal obesity for the Silent Generation (born 1925-1945), children of the Great Depression; Baby Boomers (born 1946-1964); or Generation X (born 1965-1980). Cohort effects for prevalence of abdominal obesity were estimated using the median polish method with data collected from the National Health and Nutrition Examination Survey (NHANES) between 1988 and 2008. Respondents were aged 20-74 years. RESULTS: After taking into account age effects and ubiquitous secular changes, the Silent Generation and Generation X had higher cohort-specific prevalence of abdominal obesity than the Baby Boomers. Effects were more pronounced in women than men. CONCLUSIONS: This work presents a novel finding: evidence that the birth cohorts of the post-World War II Baby Boom appeared to have uniquely low cohort effects on abdominal obesity. The growing prosperity of the post-World War II US may have exposed the baby-boom generation to lower levels of psychosocial and socioeconomic stress than the previous or subsequent generations. By identifying factors associated with the Baby Boomers' low cohort-specific sensitivity to the obesogenic environment, the obesity prevention community can identify early-life factors that can protect future generations from excess weight gain.


Assuntos
Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Inquéritos Nutricionais , Obesidade Abdominal/epidemiologia , Crescimento Demográfico , Adulto , Distribuição por Idade , Idoso , Índice de Massa Corporal , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Efeito de Coortes , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade Abdominal/etiologia , Obesidade Abdominal/prevenção & controle , Prevalência , Fatores de Risco , Fatores Socioeconômicos , Fatores de Tempo , Estados Unidos/epidemiologia
4.
Arzneimittelforschung ; 44(9): 1032-43, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7986240

RESUMO

The novel compounds SDI 157 (2-methyl-4(4-N,N-dimethylaminosulfonyl-1-piperazino)pyrimid ine, CAS 131816-54-1) and SDI 158 (2-hydroxymethyl-4-(4-N,N-dimethylaminosulfonyl-1- piperazino) pyrimidine, CAS 140687-51-0) have been found to be inhibitors of sorbitol dehydrogenase. In normal and diabetic animals both compounds induced a dose-dependent increase of tissue sorbitol, especially in the peripheral nerve, without alteration of the blood glucose. In contrast to SDI 158, SDI 157 does not act in vitro. However, in the isolated perfused rat liver SDI 157 induced a high sorbitol release and plasma samples of animals treated with SDI 157 induced a sorbitol accumulation in vitro in erythrocytes like SDI 158. SDI 157 seems to be a prodrug. In accordance with the polyol theory, the chronic administration of SDI 157 to diabetic rats accelerated the cataract development and depleted the lens of total and oxidized glutathione. Surprisingly, however, it accelerated the motor nerve conduction velocity in normal and diabetic rats, normalized the glomerular filtration rate in diabetic rats and did not induce retinal capillary lesions in normal rats or aggravate those in diabetic rats. At single oral doses up to 100 mg/kg, SDI 157, was well tolerated by diabetic and normal rats. Except for a reduction of drinking water consumption, the chronic administration of SDI 157 in drinking water at doses up to 100 mg/kg per day had no side effects in normal, diabetic and galactoselfructose-rich diet rats.


Assuntos
Pirimidinas/farmacologia , Sorbitol/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Glicemia/metabolismo , Catarata/induzido quimicamente , Diabetes Mellitus Experimental/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Eritrócitos/metabolismo , Taxa de Filtração Glomerular/efeitos dos fármacos , Glutationa/sangue , Técnicas In Vitro , Lactatos/sangue , Ácido Láctico , Fígado/metabolismo , Masculino , Neurônios Motores/efeitos dos fármacos , Condução Nervosa/efeitos dos fármacos , Coelhos , Ratos , Vasos Retinianos/efeitos dos fármacos , Ovinos , Sorbitol/sangue , Sorbitol/urina
5.
Appl Microbiol Biotechnol ; 32(5): 511-7, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1366437

RESUMO

The production of the lanthionine-containing polypeptide antibiotics gallidermin from Staphylococcus gallinarum TU 3928 and pep 5 from S. epidermidis 5 is investigated with respect to regulation and stimulation of productivity by media components, optimization of both the media used and the fermentation process and is compared to the production of the lantibiotic epidermin from S. epidermidis TU 3298. Efficient methods for rapid quantification of lantibiotics, optimization of the media and a primary enrichment by adsorption chromatography are reported.


Assuntos
Antibacterianos , Fermentação/fisiologia , Peptídeos , Staphylococcus epidermidis/metabolismo , Staphylococcus/metabolismo , Alanina/análogos & derivados , Alanina/metabolismo , Sequência de Aminoácidos , Bacteriocinas , Cromatografia em Gel , Meios de Cultura , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Biossíntese Peptídica , Peptídeos Cíclicos/biossíntese , Peptídeos Cíclicos/metabolismo , Sulfetos
6.
Acta Radiol ; 29(2): 237-42, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-2965911

RESUMO

The present study was initiated by a severe complication in a patient with renal dysfunction who developed cortical blindness and weakness of her left extremities 30 hours following renal and abdominal angiography. To evaluate the impact of prolonged high serum concentrations of contrast medium (CM) this clinical situation was simulated in a laboratory model using sheep with elevated serum levels of contrast medium maintained for 48 hours. The experimental data did not support the theory that the prolonged exposure to high circulating levels of contrast medium (4 ml/kg body weight of meglumine diatrizoate 60%) is sufficient alone to cause penetration of the blood-brain barrier.


Assuntos
Barreira Hematoencefálica , Encéfalo/efeitos dos fármacos , Diatrizoato de Meglumina/efeitos adversos , Idoso , Angiografia/efeitos adversos , Animais , Anuria/fisiopatologia , Encéfalo/diagnóstico por imagem , Hemorragia Cerebral/diagnóstico por imagem , Diatrizoato de Meglumina/administração & dosagem , Diatrizoato de Meglumina/sangue , Extravasamento de Materiais Terapêuticos e Diagnósticos/diagnóstico por imagem , Feminino , Humanos , Ovinos , Tomografia Computadorizada por Raios X
7.
Acta Radiol ; 28(4): 375-81, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-2958049

RESUMO

Technical aspects on surface coil magnetic resonance imaging of the spine using a superconducting system with a field strength of 1.5 tesla are described. By using a flat surface coil instead of the body coil the image quality was markedly improved and the signal-to-noise ratio (S/N) was increased approximately 2.6 times. Small voxels resulted in low S/N. The best image quality was achieved with a slice thickness of 5 mm, a field of view of 20 to 24 cm and a matrix of 256 X 256. Interleaved slices provided superior image quality compared with contiguous slices at the expense of acquisition time. For sagittal images the phase encoding gradient should be in the cranio-caudal direction to minimize motion artifacts. To obtain T1 and T2 images of high quality, spin echo pulse sequences with TR 600/TE 20 ms and TR 2000/TE 40 to 80 ms are useful.


Assuntos
Coluna Vertebral/anatomia & histologia , Espaço Epidural/anatomia & histologia , Humanos , Aumento da Imagem , Imageamento por Ressonância Magnética/métodos , Controle de Qualidade , Espaço Subaracnóideo/anatomia & histologia
8.
Radiology ; 163(2): 455-8, 1987 May.
Artigo em Inglês | MEDLINE | ID: mdl-3562826

RESUMO

Lumbar myelography was performed with high volumes of iohexol (15-24 ml) at a concentration of 180 mgI/ml (average dose, 20 ml) in 48 patients. In 44 patients receiving more than the currently recommended upper dose limit of 17 ml, the frequency of headache (41%), nausea (14%), and vomiting (9%) was comparable to results for routine-dose lumbar metrizamide myelography. Overall, adverse reactions were more frequent, particularly at the highest dose levels, than reported for conventional-dose iohexol myelography. However, there were no occurrences of neuropsychiatric disorder, encephalopathy, or seizure. High-dose technique allows superior visualization of upper lumbar and conus detail and may be advantageous in patients with large subarachnoid spaces and in multi-level examinations. This study supports the results of previous trials that suggested the relative safety of iohexol as a contrast agent and extends those observations to a higher dose range. Because of the increased rate of adverse reactions at the highest dose levels (despite the absence of major adverse reactions), iohexol should continue to be used conservatively, with doses carefully tailored to each examination.


Assuntos
Iohexol/administração & dosagem , Mielografia/métodos , Adulto , Idoso , Avaliação de Medicamentos , Feminino , Seguimentos , Cefaleia/induzido quimicamente , Humanos , Iohexol/efeitos adversos , Masculino , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Risco
9.
Radiology ; 160(2): 363-7, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3726114

RESUMO

Examination with magnetic resonance imaging of 40 patients with confirmed diagnoses of multiple sclerosis showed that corpus callosum involvement is common. Thirty percent of the patients had focal callosal lesions similar to those described in the pathology literature. Long, inner callosal-subcallosal lesions were found in 55% of patients. These lesions had signal characteristics similar to those of noncallosal periventricular lesions. Diffuse moderate to severe atrophy of the corpus callosum was noted in 40% of patients, with one exception concurrent with inner callosal lesions. The nature of the inner callosal lesions is not known, since these lesions are not typically described in the literature. These lesions may represent demyelination or increased water content and may be the precursor to atrophy that progresses from the ependymal surface toward the outer fibers of the corpus callosum.


Assuntos
Corpo Caloso/patologia , Esclerose Múltipla/diagnóstico , Adulto , Idoso , Ventrículos Cerebrais/patologia , Corpo Caloso/anatomia & histologia , Feminino , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade
10.
J Comput Assist Tomogr ; 9(4): 725-7, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3894439

RESUMO

The CT findings in two patients with the unusual presentation of malignant lymphoma in the skull are described. The dominant CT findings were contrast enhanced large soft tissue masses without calcifications on both sides of the bone with very little or no changes in the bone itself. This characteristic CT appearance may be helpful to differentiate primary lymphoma of the skull from other bone tumors and osteomyelitis.


Assuntos
Osso Frontal/diagnóstico por imagem , Linfoma Difuso de Grandes Células B/diagnóstico por imagem , Linfoma/diagnóstico por imagem , Neoplasias Cranianas/diagnóstico por imagem , Neoplasias de Tecidos Moles/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
11.
AJR Am J Roentgenol ; 144(1): 101-5, 1985 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3871127

RESUMO

Although adhesive capsulitis of the shoulder is a common clinical syndrome, adhesive capsulitis in other joints has rarely been reported. Four patients who developed adhesive capsulitis of the hip joint after trauma and two patients with adhesive capsulitis of the ankle, also precipitated by trauma, are described. The diagnosis of adhesive capsulitis is easily made during arthrography when a joint of low volume and high intracapsular pressure is encountered.


Assuntos
Articulação do Tornozelo/diagnóstico por imagem , Articulação do Quadril/diagnóstico por imagem , Periartrite/diagnóstico por imagem , Adulto , Traumatismos do Tornozelo , Feminino , Lesões do Quadril , Humanos , Masculino , Radiografia
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