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1.
Int J Biometeorol ; 58(10): 2165-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24619461

RESUMO

Polyethylene hutches are a popular method of housing dairy calves from 0 to 60 or more days of age, although these hutches get hot when in full sun. This study characterized the relative differences in the ability of four different types of radiant barriers to reduce black-globe temperature within these hutches. Treatments included three different types of covers (two types of laminates (Cadpak P and Cadpak ESD) and an aluminized 3.0-mil white low-density polyethylene (LDPE)) and a reflective paint (LO/MIT-1). The reflective covers were 1.8 × 3 m finished size, and covered the top and sides of the hutch down to 0.15 m above the ground, leaving the front and back exposed. The LO/MIT-1 paint covered the entire sides and roof of the hutch. Two 24-h trials 1 week apart were conducted during relatively hot and clear days in early August. Black-globe temperatures were recorded in duplicate and averaged at 20-min intervals using blackened table tennis balls mounted 0.3 m above the floor in the center of each hutch. Ambient temperature (shade) during the hottest 2-h period for both trials averaged 39.9 °C while the uncovered control averaged 41.1 °C, and LO/MIT-1 averaged 39.9 °C; both of which were significantly higher (P < 0.01) than the Cadpak P (38.9 °C), Cadpak ESD (38.6 °C), and aluminized LDPE (38.7 °C). During periods of high solar radiation, the hutches with covers had lowest black-globe temperatures followed by hutches painted with reflective paint, while control hutches had the highest temperature.


Assuntos
Abrigo para Animais , Alumínio , Animais , Bovinos , Indústria de Laticínios , Pintura , Polietileno , Energia Solar , Temperatura
2.
Nature ; 438(7069): 779-84, 2005 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-16319830

RESUMO

Saturn's largest moon, Titan, remains an enigma, explored only by remote sensing from Earth, and by the Voyager and Cassini spacecraft. The most puzzling aspects include the origin of the molecular nitrogen and methane in its atmosphere, and the mechanism(s) by which methane is maintained in the face of rapid destruction by photolysis. The Huygens probe, launched from the Cassini spacecraft, has made the first direct observations of the satellite's surface and lower atmosphere. Here we report direct atmospheric measurements from the Gas Chromatograph Mass Spectrometer (GCMS), including altitude profiles of the constituents, isotopic ratios and trace species (including organic compounds). The primary constituents were confirmed to be nitrogen and methane. Noble gases other than argon were not detected. The argon includes primordial 36Ar, and the radiogenic isotope 40Ar, providing an important constraint on the outgassing history of Titan. Trace organic species, including cyanogen and ethane, were found in surface measurements.


Assuntos
Atmosfera/química , Meio Ambiente Extraterreno/química , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Voo Espacial , Argônio/análise , Carbono/análise , Carbono/química , Isótopos/análise , Metano/análise , Metano/química , Nitrogênio/análise , Nitrogênio/química , Voo Espacial/instrumentação
3.
Org Lett ; 3(11): 1665-8, 2001 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-11405681

RESUMO

The installation of the novel N,N-dimethylglycolamide ester auxiliary onto the C(1)-position of protected neuraminic acid donors allows for the exploitation of C(1)-neighboring group participation to generate sialoside conjugates with good to excellent alpha-selectivity under a variety of sialylation protocols, including those that would otherwise lead to nonselective or beta-selective sialoside products.


Assuntos
Glicosídeos/síntese química , Indicadores e Reagentes , Conformação Molecular , Ácidos Neuramínicos/química , Estereoisomerismo
4.
Eur J Ophthalmol ; 9(3): 181-95, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10544973

RESUMO

The authors report a 46-year-old father and 17-year-old son who each presented with unilateral central retinal vein occlusion (CRVO) and bilateral abnormalities of retinal vascular perfusion. The son presented with a nonperfused CRVO in the left eye, developed traction-rhegmatogenous retinal detachment treated with vitreous surgery, and developed prolonged arteriovenous filling in the retina of the fellow eye. The father presented with progressive CRVO in the right eye, developed choroido-vitreal neovascularization following laser treatment to create a chorioretinal anastomosis, underwent vitrectomy for retinal detachment and vitreous hemorrhage in that eye, and developed prolonged arm-eye and retinal arteriovenous circulation times in the fellow eye. An extensive evaluation (including hematological studies and imaging of the major vessels of the neck) failed to reveal a predisposing cause in either patient although echocardiography disclosed a mitral valve thrombus in the father. After institution of coumadin therapy, the circulatory parameters in the fellow eye of each patient improved.


Assuntos
Oclusão da Veia Retiniana/diagnóstico , Adolescente , Progressão da Doença , Família , Angiofluoresceinografia , Humanos , Pressão Intraocular , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional , Hemorragia Retiniana/diagnóstico , Oclusão da Veia Retiniana/genética , Oclusão da Veia Retiniana/fisiopatologia , Acuidade Visual
5.
Eur J Ophthalmol ; 9(3): 165-80, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10544972

RESUMO

Central retinal vein occlusion is usually a disease of the elderly and is often associated with systemic vascular disease, e.g., hypertension, diabetes mellitus, arteriosclerotic vascular disease. Younger patients, especially those less than 45 years of age, with retinal vein occlusion should be evaluated carefully for the possibility of an underlying thrombotic tendency. The authors describe the ocular manifestations, pathogenesis, associated conditions, patient evaluation, and treatment of patients with central retinal vein occlusion.


Assuntos
Oclusão da Veia Retiniana , Fatores Etários , Transtornos da Coagulação Sanguínea/complicações , Comorbidade , Humanos , Oclusão da Veia Retiniana/etiologia , Oclusão da Veia Retiniana/terapia
6.
Adv Space Res ; 21(11): 1455-61, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-11541457

RESUMO

The Galileo Probe entered the atmosphere of Jupiter on December 7, 1995. Measurements of the chemical and isotopic composition of the Jovian atmosphere were obtained by the mass spectrometer during the descent over the 0.5 to 21 bar pressure region over a time period of approximately 1 hour. The sampling was either of atmospheric gases directly introduced into the ion source of the mass spectrometer through capillary leaks or of gas, which had been chemically processed to enhance the sensitivity of the measurement to trace species or noble gases. The analysis of this data set continues to be refined based on supporting laboratory studies on an engineering unit. The mixing ratios of the major constituents of the atmosphere hydrogen and helium have been determined as well as mixing ratios or upper limits for several less abundant species including: methane, water, ammonia, ethane, ethylene, propane, hydrogen sulfide, neon, argon, krypton, and xenon. Analysis also suggests the presence of trace levels of other 3 and 4 carbon hydrocarbons, or carbon and nitrogen containing species, phosphine, hydrogen chloride, and of benzene. The data set also allows upper limits to be set for many species of interest which were not detected. Isotope ratios were measured for 3He/4He, D/H, 13C/12C, 20Ne/22Ne, 38Ar/36Ar and for isotopes of both Kr and Xe.


Assuntos
Atmosfera/química , Meio Ambiente Extraterreno , Gases/análise , Júpiter , Voo Espacial/instrumentação , Atmosfera/análise , Pressão Atmosférica , Hélio/análise , Hidrocarbonetos/análise , Hidrogênio/análise , Espectrometria de Massas , Gases Nobres/análise , Astronave/instrumentação
7.
J Geophys Res ; 103(E10): 22831-45, 1998 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-11543372

RESUMO

The Galileo probe mass spectrometer determined the composition of the Jovian atmosphere for species with masses between 2 and 150 amu from 0.5 to 21.1 bars. This paper presents the results of analysis of some of the constituents detected: H2, He, Ne, Ar, Kr, Xe, CH4, NH3, H2O, H2S, C2 and C3 nonmethane hydrocarbons, and possibly PH3 and Cl. 4He/H2 in the Jovian atmosphere was measured to be 0.157 +/- 0.030. 13C/C12 was found to be 0.0108 +/- 0.0005, and D/H and 3He/4He were measured. Ne was depleted, < or = 0.13 times solar, Ar < or = 1.7 solar, Kr < or = 5 solar, and Xe < or = 5 solar. CH4 has a constant mixing ratio of (2.1 +/- 0.4) x 10(-3) (12C, 2.9 solar), where the mixing ratio is relative to H2. Upper limits to the H2O mixing ratio rose from 8 x 10(-7) at pressures <3.8 bars to (5.6 +/- 2.5) x 10(-5) (16O, 0.033 +/- 0.015 solar) at 11.7 bars and, provisionally, about an order of magnitude larger at 18.7 bars. The mixing ratio of H2S was <10(-6) at pressures less than 3.8 bars but rose from about 0.7 x 10(-5) at 8.7 bars to about 7.7 x 10(-5) (32S, 2.5 solar) above 15 bars. Only very large upper limits to the NH3 mixing ratio have been set at present. If PH3 and Cl were present, their mixing ratios also increased with pressure. Species were detected at mass peaks appropriate for C2 and C3 hydrocarbons. It is not yet clear which of these were atmospheric constituents and which were instrumentally generated. These measurements imply (1) fractionation of 4He, (2) a local, altitude-dependent depletion of condensables, probably because the probe entered the descending arm of a circulation cell, (3) that icy planetesimals made significant contributions to the volatile inventory, and (4) a moderate decrease in D/H but no detectable change in (D + 3He)/H in this part of the galaxy during the past 4.6 Gyr.


Assuntos
Atmosfera/química , Júpiter , Voo Espacial/instrumentação , Calibragem , Carbono/análise , Meio Ambiente Extraterreno , Gases/análise , Hélio/análise , Hidrocarbonetos/análise , Hidrogênio/análise , Espectrometria de Massas/instrumentação , Espectrometria de Massas/métodos , Gases Nobres/análise , Astronave/instrumentação
8.
Science ; 272(5263): 846-9, 1996 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-8629016

RESUMO

The composition of the jovian atmosphere from 0.5 to 21 bars along the descent trajectory was determined by a quadrupole mass spectrometer on the Galileo probe. The mixing ratio of He (helium) to H2 (hydrogen), 0.156, is close to the solar ratio. The abundances of methane, water, argon, neon, and hydrogen sulfide were measured; krypton and xenon were detected. As measured in the jovian atmosphere, the amount of carbon is 2.9 times the solar abundance relative to H2, the amount of sulfur is greater than the solar abundance, and the amount of oxygen is much less than the solar abundance. The neon abundance compared with that of hydrogen is about an order of magnitude less than the solar abundance. Isotopic ratios of carbon and the noble gases are consistent with solar values. The measured ratio of deuterium to hydrogen (D/H) of (5 +/- 2) x 10(-5) indicates that this ratio is greater in solar-system hydrogen than in local interstellar hydrogen, and the 3He/4He ratio of (1.1 +/- 0.2) x 10(-4) provides a new value for protosolar (solar nebula) helium isotopes. Together, the D/H and 3He/4He ratios are consistent with conversion in the sun of protosolar deuterium to present-day 3He.


Assuntos
Atmosfera , Meio Ambiente Extraterreno , Júpiter , Água/análise , Amônia/análise , Carbono/análise , Hélio/análise , Hidrogênio/análise , Espectrometria de Massas , Nitrogênio/análise , Gases Nobres/análise , Oxigênio/análise
9.
Eur J Radiol ; 21(3): 225-32, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8777915

RESUMO

The clinical, radiographic, and pathologic features of 17 patients with documented peripheral primitive neuroectodermal tumor (PNET) were evaluated in a retrospective study. The age at diagnosis ranged from 9 months to 46 years (median, 15.8 years). Primary sites of involvement were the abdomen (n = 8), extremities (n = 5), chest (n = 1), temporal bone (n = 1), maxilla (n = 1), and diploe (n = 1). At the time of diagnosis, six patients had distant metastases; all of these patients died, with an average survival of 8.8 months. Radiologic workup included standard radiographs, ultrasound, computed tomography (CT), magnetic resonance imaging (MRI), and bone scintigraphy. The radiographic appearance of these tumors was not specific for differentiation of PNETs from other types of bone and soft tissue tumors. The typical appearance resembled large non-calcified, soft tissue masses with cystic or necrotic areas. Heterogeneous enhancement with intravenous contrast agents was evident on CT, as was an intermediate signal intensity on Tl-weighted images and hyperintense signal on T2-weighted and STIR sequences. After gadolinium administration, variable enhancement was seen. MRI and CT were useful in predicting resectability, in detecting distant metastases, and in the evaluation of response to treatment. Surgery was performed in all cases, either for definitive diagnosis or for therapy. All patients received combined chemotherapy and radiotherapy and five patients received autologous bone marrow transplantation. Clinical follow-up was obtained over a mean period of 3 years (range 1 day to 6 years). Prognosis was poor with a median survival of 3.4 years. Our experience in 17 patients with peripheral neuroectodermal tumors indicates that although their radiologic features are non-specific, they should be included in differential diagnosis of soft tissue tumors of aggressive behavior, especially in a young age group. CT and MRI are useful in delineating the extent and resectability of tumor and in monotoring treatment.


Assuntos
Neoplasias Ósseas/diagnóstico , Imageamento por Ressonância Magnética , Tumores Neuroectodérmicos Primitivos Periféricos/diagnóstico , Tumores Neuroectodérmicos Primitivos/diagnóstico , Neoplasias de Tecidos Moles/diagnóstico , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/terapia , Criança , Pré-Escolar , Terapia Combinada , Feminino , Seguimentos , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Tumores Neuroectodérmicos Primitivos/mortalidade , Tumores Neuroectodérmicos Primitivos/terapia , Tumores Neuroectodérmicos Primitivos Periféricos/mortalidade , Tumores Neuroectodérmicos Primitivos Periféricos/terapia , Neoplasias de Tecidos Moles/mortalidade , Neoplasias de Tecidos Moles/terapia , Taxa de Sobrevida
10.
J Urol ; 151(6): 1518-21, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8189560

RESUMO

Despite current practice there is no evidence to demonstrate the efficacy of intraurethral lidocaine gel as an anesthetic for rigid cystoscopy. To evaluate the usefulness of lidocaine in decreasing pain associated with cystoscopy, we performed a prospective, randomized, controlled, double-blind study comparing lidocaine gel with a water based lubricant. The effects of pre-procedure anxiety and prior experience with cystoscopy on pain perception were also evaluated. Physician perception of pain experienced by the patient was compared with the actual pain experienced. We found no decrease in pain perception in men or women following lidocaine gel instillation with a 5 or 10-minute dwell time compared to instillation of the plain lubricant. Increased preprocedure anxiety correlated with increased pain perception in women. Personal experience with prior cystoscopic procedures significantly decreased the current pain perception in men. Physicians underestimated the patient pain perception in all groups. Overall, we found the use of lidocaine gel to be of no benefit in routine rigid cystoscopy. Lowering pre-procedure anxiety may decrease the amount of pain perceived by women but not by men.


Assuntos
Anestesia Local , Ansiedade/prevenção & controle , Cistoscopia/efeitos adversos , Lidocaína/administração & dosagem , Dor/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Ansiedade/etiologia , Método Duplo-Cego , Feminino , Humanos , Instilação de Medicamentos , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Medição da Dor/efeitos dos fármacos , Estudos Prospectivos , Fatores Sexuais , Inquéritos e Questionários , Uretra
11.
J Magn Reson Imaging ; 4(2): 169-72, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8180456

RESUMO

The evaluation of loose bodies in the elbow is usually done by means of clinical examination, radiography, and postarthrographic computed tomography (CT). The authors review their experience with magnetic resonance (MR) imaging in place of post-arthrographic CT for the evaluation of loose bodies in the elbow. The prospective interpretation of MR studies of the elbow in 20 patients was compared with arthroscopic findings. All elbows were imaged in multiple planes with thin sections, surface coils, and combinations of T1, T2, and proton-density weighting. The sensitivity for showing loose bodies with MR imaging was 100%, and the specificity was 67%. Because this was a nonblinded study, the results are biased and caution must be used when extrapolating these results to the general population. In this limited experience, MR imaging has reliably shown loose bodies in the elbow, and in the authors' institutions has replaced postarthrographic CT for that purpose.


Assuntos
Articulação do Cotovelo/patologia , Corpos Livres Articulares/diagnóstico , Imageamento por Ressonância Magnética , Adolescente , Adulto , Artroscopia , Feminino , Humanos , Corpos Livres Articulares/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X
12.
Am J Vet Res ; 52(7): 1128-31, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1892268

RESUMO

Full-thickness skin wounds were created on the dorsum of both metacarpi in 8 horses. Three topical treatment regimens were studied. All wounds were bandaged with a nonadherent dressing, which was held in place with a snug elastic wrap. Group-A wounds were treated with a proprietary topical wound medication that consisted of a spray and an ointment. Group-B wounds were treated with the same regimen, except the putative active ingredients in the ointment were omitted. Group-C wounds were treated with a dry nonadherent bandage only. Wound dressings were changed every day and the limbs were photographed every other day until the wounds were healed. Specimens of normal skin and biopsy specimens of healed wounds were examined histologically and were assayed for hydroxyproline content. Wound healing measurements quantitated for each wound were number of days to healing, maximal wound size attained, day wound contraction commenced, day epithelium first noticed, rate of wound contraction, final wound size, and fraction of the wound that healed by contraction. The cosmetic appearance of the healed wounds was also graded. Significant differences were not noticed in hydroxyproline content, histologic appearance, or any of the wound healing measurements between treatment groups. The cosmetic appearance of healed group-A and -B wounds was significantly better than the appearance of group-C wounds. The topical treatment regimens studied neither enhanced nor inhibited wound healing in this study.


Assuntos
Colágeno/metabolismo , Cavalos/lesões , Pele/lesões , Cicatrização , Compostos de Zinco , Administração Tópica , Aerossóis , Hidróxido de Alumínio/administração & dosagem , Hidróxido de Alumínio/uso terapêutico , Animais , Bandagens/veterinária , Carbonato de Cálcio/administração & dosagem , Carbonato de Cálcio/uso terapêutico , Cloretos/administração & dosagem , Cloretos/uso terapêutico , Combinação de Medicamentos , Cavalos/fisiologia , Hidroxiprolina/análise , Hidróxido de Magnésio/administração & dosagem , Hidróxido de Magnésio/uso terapêutico , Pomadas , Piridoxina/administração & dosagem , Piridoxina/uso terapêutico , Fenômenos Fisiológicos da Pele , Vitamina A/administração & dosagem , Vitamina A/uso terapêutico , Zinco/administração & dosagem , Zinco/uso terapêutico
13.
J Urol ; 145(2): 294-6, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1988720

RESUMO

Fertility and potential fertility were evaluated in 9 young men on cyclosporine A therapy following renal transplantation. Semen analysis was normal in most parameters in 8 patients as was testicular hormonal function. Of 4 men who had attempted to impregnate their wives 3 succeeded. Cyclosporine A does not seem to affect adversely fertility in men.


Assuntos
Ciclosporinas/efeitos adversos , Fertilidade/efeitos dos fármacos , Transplante de Rim/fisiologia , Sêmen/efeitos dos fármacos , Testículo/efeitos dos fármacos , Adulto , Ciclosporinas/uso terapêutico , Humanos , Masculino , Contagem de Espermatozoides/efeitos dos fármacos , Motilidade dos Espermatozoides/efeitos dos fármacos
14.
J Dent Res ; 63(10): 1201-5, 1984 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6592201

RESUMO

The fluoride content of both sound and white-spot enamel was determined in deciduous teeth collected from an anti-caries clinical trial which compared a 0.243% NaF dentifrice, a 0.4% SnF2 dentifrice, and a placebo. A microdrill enamel biopsy technique was developed for the analysis of white spots. No correlations were found between caries increment scores and the fluoride content of sound enamel. The enamel in white spots from users of the 0.243% NaF dentifrice had a mean fluoride content higher than that from users of the 0.4% SnF2 dentifrice. There was a negative correlation between fluoride found in white-spot enamel and caries increment scores. It is hypothesized that fluoride affects the caries rate by its control over the rate of remineralization in previously demineralized areas.


Assuntos
Cárie Dentária/metabolismo , Esmalte Dentário/análise , Fluoretos/análise , Dente Decíduo/análise , Biópsia/métodos , Cárie Dentária/prevenção & controle , Dentifrícios , Humanos , Placebos , Fluoreto de Sódio/administração & dosagem , Fluoreto de Sódio/uso terapêutico , Fluoretos de Estanho/administração & dosagem , Fluoretos de Estanho/uso terapêutico
16.
Radiology ; 148(2): 393-6, 1983 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6867332

RESUMO

An ROC curve analysis of mammography is presented. This study is based on a blind interpretation of radiographs of patients who underwent screening during the Oklahoma Breast Cancer Detection Demonstration Project (BCDDP). In particular, we evaluated the accuracy of mammography based on 38 incidence cancer cases. Incidence cases are those that develop in a patient after an initial visit and at least one additional annual visit before a biopsy is performed. Using 40 normal subjects, a sensitivity of 72% was attained at a 28% false positive rate. We also evaluated the contribution of viewing radiographs of both breasts (right and left) simultaneously as compared with viewing radiographs of the individual breasts singly. In cases on the threshold of detectability, the breast that did not result in the cancer diagnosis was occasionally identified as the most suspicious for cancer. When mammograms of the two breasts were compared, the false positive rate was lower. These results can be used to assess various screening strategies and to yield a more realistic accuracy estimate of mammography on a rescreened population than is currently available.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Mamografia , Biópsia , Feminino , Humanos , Pessoa de Meia-Idade , Oklahoma , Projetos Piloto
20.
Cancer ; 38(5): 1931-5, 1976 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-991107

RESUMO

The thermal and graphic criteria which should be used to evaluate breast thermograms are outlined. Thermograms are then categorized as normal, suspicious, or abnormal on the basis of the criteria outlined. It is hoped that these criteria can be used widely to standardize breast thermographic evaluation.


Assuntos
Neoplasias da Mama/diagnóstico , Termografia , Feminino , Humanos , Postura , Termografia/instrumentação
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