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1.
Arch Intern Med ; 160(10): 1495-500, 2000 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-10826464

RESUMEN

BACKGROUND: Hypertension has been linked to several psychological factors, including depression, but the relation between hypertension incidence and depressive symptoms has not been adequately examined. OBJECTIVE: To determine if depressive symptoms independently predict hypertension incidence. DESIGN AND SETTING: A prospective, multicenter, epidemiological cohort of young adults (aged 23-35 years at study entry) from the general community without hypertension followed up for 5 years. SUBJECTS: A sample of 3343 adults from 4 urban areas stratified for race (black and white) from the CARDIA (Coronary Artery Risk Development in Young Adults) study. MAIN OUTCOME MEASURE: Hypertension incidence, which was defined as blood pressure higher than 160/95 mm Hg (assessed on a single occasion) or the use of prescribed antihypertensive medication. RESULTS: Participants with high scores (> or = 16) on the Center for Epidemiological Studies Depression (CES-D) Scale were at significant risk for hypertension incidence compared with those with low CES-D scores (< or =7; odds ratio, 2.10; 95% confidence interval, 1.22-3.61) after adjustment for other hypertension risk factors (eg, age, resting systolic blood pressure at the 5-year examination, physical activity, daily alcohol use, parental history of hypertension, education, presence of diabetes mellitus or heart disease, sex, and race) in fixed logistic models. Those with intermediate depressive symptoms (CES-D scores 8-15) were also at significant risk (adjusted odds ratio, 1.78; 95% confidence interval, 1.06-2.98). These associations were significant in blacks alone but were not found in whites, who had a lower hypertension incidence (29 [2%] of 1806) than blacks (89 [6%] of 1537). CONCLUSIONS: Depressive symptoms were predictive of later hypertension incidence in young adults, and young blacks with depressive symptoms were at high risk of developing hypertension.


Asunto(s)
Depresión/psicología , Hipertensión/psicología , Adulto , Estudios de Cohortes , Depresión/diagnóstico , Depresión/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Hipertensión/diagnóstico , Hipertensión/epidemiología , Incidencia , Masculino , Estudios Prospectivos , Factores de Riesgo
2.
J Invest Dermatol ; 66(4): 239-41, 1976 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-178805

RESUMEN

Adenosine 3',5'-monophosphate (cyclic AMP) has been localized in mouse epidermal cells using an immunofluorescent technique. Within 10 min following the intraperitoneal injection of isoproterenol or 30 hr following the topical application of croton oil in acetone, staining was clearly visible in the cytoplasm of the basal cells.


Asunto(s)
AMP Cíclico/análisis , Piel/análisis , Animales , Aceite de Crotón/farmacología , Técnica del Anticuerpo Fluorescente , Isoproterenol/farmacología , Ratones
3.
Am J Trop Med Hyg ; 34(3): 435-7, 1985 May.
Artículo en Inglés | MEDLINE | ID: mdl-3890575

RESUMEN

A clinical field trial was conducted to determine if mefloquine is effective in the treatment of malaria due to Plasmodium vivax. Forty patients with P. vivax malaria were treated with either mefloquine, chloroquine or chloroquine plus primaquine and followed for 28 days. All patients responded rapidly and were cured. There were no significant side effects.


Asunto(s)
Malaria/tratamiento farmacológico , Quinolinas/uso terapéutico , Adulto , Cloroquina/uso terapéutico , Ensayos Clínicos como Asunto , Quimioterapia Combinada , Humanos , Mefloquina , Plasmodium vivax , Primaquina/uso terapéutico , Distribución Aleatoria
4.
Am J Trop Med Hyg ; 32(3): 631-2, 1983 May.
Artículo en Inglés | MEDLINE | ID: mdl-6344673

RESUMEN

Mefloquine, a new antimalarial which has been effective in curing malaria due to Plasmodium falciparum and P. vivax, was used for the first time in a patient infected with P. malariae. Treatment was successful, and the relatively long parasite clearance time and fever clearance time were probably characteristic of P. malariae rather than true drug resistance.


Asunto(s)
Malaria/tratamiento farmacológico , Quinolinas/uso terapéutico , Adulto , Humanos , Masculino , Mefloquina , Plasmodium malariae
5.
Am J Trop Med Hyg ; 30(1): 161-4, 1981 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7212162

RESUMEN

An epidemic of Oropouche fever occurred in Santarém, Pará, Brazil in 1975. In the first survey for Oropouche antibodies involving a random sample of an entire city, infection rates varied from 0-44%, depending on the specific area within the city. Women had higher infection rates than men, but this difference was statistically significant only for persons older than 10 years of age. An analysis of school data showed that pupils in the evening classes had a greater increase in absenteeism during the epidemic period than those attending morning or afternoon classes. These data are compatible with the concept that Culicoides paraensis rather than Culex pipiens quinquefasciatus is the main vector of Oropouche virus in Brazil.


Asunto(s)
Infecciones por Arbovirus/epidemiología , Animales , Infecciones por Arbovirus/etiología , Brasil , Ceratopogonidae/microbiología , Culex/microbiología , Brotes de Enfermedades/epidemiología , Femenino , Humanos , Insectos Vectores , Masculino , Factores Sexuales , Factores de Tiempo
6.
Am J Trop Med Hyg ; 30(1): 165-71, 1981 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7212163

RESUMEN

Urban epidemics of Oropouche (ORO) fever in three municipalities in Pará, Brazil were studied in 1975. Culicoides paraensis (Goeldi) were collected during each of the epidemics and there was a positive correlation, by study areas within the city of Santarém, between human seropositivity to ORO virus and population densities of C. paraensis and Culex quinquefasciatus Say. The best numerical correlation was with populations of C. paraensis. The relative absence of other species in the areas of high disease attack rates was further evidence C. paraensis were the probable vectors of ORO virus. These biting midges were found to bite readily inside of houses, with an indoor/outdoor ratio of 29%, and were most active around 1700-1800 hours. Other biological observations on C. paraensis are presented.


Asunto(s)
Infecciones por Arbovirus/epidemiología , Ceratopogonidae/microbiología , Culex/microbiología , Insectos Vectores , Animales , Infecciones por Arbovirus/transmisión , Brasil , Brotes de Enfermedades/epidemiología , Humanos , Factores de Tiempo
7.
Am J Trop Med Hyg ; 54(3): 284-8, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8600767

RESUMEN

A hospital-based, case-control study was conducted to measure risk factors for hemorrhagic fever with renal syndrome in Korean soldiers. Between October 1989 and January 1992, 196 cases and 295 controls were admitted into the study. Information was collected on behavioral and environmental variables, and the data were analyzed by multiple logistic regression. The strongest risk factors were seeing Apodemus in the area (odds ratio [OR] = 4.9), living in a primitive dwelling such as a lean-to (OR = 3.9), and being exposed to dust (OR = 3.7). The most protective factors were living in barracks (OR = 0.3-0.5) and self-reported use of any insecticide or insect repellent (OR = 0.5).


Asunto(s)
Fiebre Hemorrágica con Síndrome Renal/epidemiología , Personal Militar , Adulto , Animales , Estudios de Casos y Controles , Vectores de Enfermedades , Polvo , Fiebre Hemorrágica con Síndrome Renal/etiología , Vivienda , Humanos , Repelentes de Insectos , Insectos , Insecticidas , Entrevistas como Asunto , Corea (Geográfico)/epidemiología , Masculino , Muridae , Factores de Riesgo
8.
FEMS Microbiol Lett ; 106(2): 135-8, 1993 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-8454177

RESUMEN

A hybrid trpPO:lacO regulatory sequence was cloned upstream of a promoterless lacZ gene and recombined onto a lambda bacteriophage. Escherichia coli lysogens representing the four possible phenotypes for lacI and trpR were constructed and the synthesis of beta-galactosidase was assayed under various growth conditions. The results illustrated that both control elements could be efficiently and independently regulated by the addition or omission of appropriate accessory molecules.


Asunto(s)
Escherichia coli/genética , Genes Bacterianos , Regiones Operadoras Genéticas , Regiones Promotoras Genéticas , beta-Galactosidasa/biosíntesis , Clonación Molecular , Escherichia coli/enzimología , Indoles/farmacología , Operón Lac , Triptófano/farmacología
9.
Trans R Soc Trop Med Hyg ; 76(5): 664-7, 1982.
Artículo en Inglés | MEDLINE | ID: mdl-6758224

RESUMEN

Falciparum malaria in 104 Thai patients was treated with either Mefloquine or Fansidar and patients were examined for parasitaemia for the next 28 days. All but one of the 40 patients treated with Mefloquine were cured, but the cure rates for Fansidar were only 9 . 1% for the two-tablet regimen and 19 . 4% for the three-tablet regimen. Most failures were classified as RII. Serum sulpha levels indicated that the Fansidar was being absorbed. Immediate steps should be taken to eliminate this focus of resistance and to protect against further resistance to Fansidar by using it in combination with another effective anti-malarial and by vigorous vector control measures.


Asunto(s)
Antimaláricos/uso terapéutico , Malaria/tratamiento farmacológico , Pirimetamina/uso terapéutico , Quinolinas/uso terapéutico , Sulfadoxina/uso terapéutico , Sulfanilamidas/uso terapéutico , Combinación de Medicamentos/uso terapéutico , Farmacorresistencia Microbiana , Humanos , Mefloquina , Plasmodium falciparum
10.
Theriogenology ; 15(4): 335-44, 1981 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16725593

RESUMEN

Fifty ejaculates, ten from each of 5 mature stallions, were utilized to study the effects of calcium and fatty acids on equine spermatozoa which were isolated in 3% Bovine Serum Albumin (BSA). The ejaculates were evaluated for percent motile spermatozoa, rate of forward movement, debris, primary abnormalities and secondary abnormalities. The isolation procedure consisted of layering 2 ml of diluted semen (100 x 10(6) spermatozoa/ml) over 6 ml of 3% BSA in 13 x 125 mm columns in a water bath (37 degrees C). After 30 min., the top semen layer and upper half of the BSA layer were withdrawn from all columns and the lower half of the BSA was re-evaluated. A 2 x 2 factorial arrangement of treatments was utilized with either the inclusion or omission of calcium or fatty acids in the BSA isolation media. The percent motile spermatozoa and rate of forward movement were increased (P<.01) when fatty acids were included in the isolation media but decreased (P<.01) when they were omitted. The highest percent motile spermatozoa and rate of forward movement were observed with BSA in the presence of fatty acids and omission of calcium. The calcium by fatty acid interaction, stallion effect and stallion by treatment interaction were significant for percent motile spermatozoa. Less debris was observed in all samples of isolated spermatozoa when compared with the initial estimate. Isolation resulted in a reduction of (P<.01) the primary abnormalities. Also, fewer (P<.01) secondary abnormalities were observed after isolation in all treatments except 4 (-FA+Ca) than were found in the ejaculate sample.

16.
Ciba Found Symp ; 182: 92-110; discussion 110-20, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7835159

RESUMEN

Animal embryos can be classified into three types depending on the time when the adult body form is specified--after metamorphosis, progressively by addition of posterior segments, or as a single event early in development. Segregation of germ cells correlates with specification of adult body form. When the adult body form is specified late in development, e.g. after metamorphosis (molluscs, echinoderms, cirripedes, hemichordates, cephalochordates and ascidians), germ cells appear in the early adult and at the site where the gonads will develop. When the adult body form is specified progressively during development by the sequential addition of posterior segments (annelids, onychophorans and most arthropods) germ cells are segregated either before or during addition of segments, in close association with the growth zone. In nematodes, chaetognaths, collembolans, higher holometabolous insects and vertebrates, the adult body form is specified early in development and germ cells are typically segregated correspondingly early and in extraembryonic regions. Therefore, as a general conclusion, germ cells appear to be segregated in locations and/or at times that exclude them from the process of specification of adult body form. Germ plasm is restricted to embryos in which exclusion of germ cells is difficult because the embryo is small or the signal specifying adult body form is pervasive. A possible role for germ plasm is thus as additional protection for the cells from the processes specifying adult body form.


Asunto(s)
Grupos de Población Animal/embriología , Evolución Biológica , Células Germinativas/citología , Morfogénesis , Animales , Embrión no Mamífero , Larva , Metamorfosis Biológica
17.
Epidemiology ; 8(3): 243-6, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9115017

RESUMEN

The case-crossover design is a new method for studying acute effects of transient exposures, in which cases serve as their own controls. To assess the validity, strengths, and weaknesses of the design, we used both the case-crossover method and the traditional case-control method of multivariate analysis with data collected from 196 cases and 295 hospital controls to study risk factors for hemorrhagic fever with renal syndrome in Korean soldiers. Both case-control and case-crossover methods showed that living in primitive field conditions, exposure to dust, and exposure to rodents were risk factors; use of insecticides or insect repellents was protective. Odds ratios from the case-crossover method were generally somewhat higher for risk factors and lower for protective factors. The case-crossover technique has great potential as a powerful, cost-effective way to assess risk factors for conditions such as infectious diseases and injuries, while avoiding some of the bias and logistical problems of traditional study designs.


Asunto(s)
Fiebre Hemorrágica con Síndrome Renal/etiología , Adulto , Sesgo , Estudios de Casos y Controles , Intervalos de Confianza , Estudios Cruzados , Exposición a Riesgos Ambientales , Métodos Epidemiológicos , Humanos , Corea (Geográfico) , Personal Militar , Análisis Multivariante , Oportunidad Relativa , Factores de Riesgo
18.
Development ; 103(3): 507-18, 1988 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3246221

RESUMEN

In the unfertilized egg, germ plasm is widely distributed throughout the vegetal subcortex in small islets. Following fertilization or artificial activation, the location and organization changes, and by the 4- to 8-cell stage the germ plasm forms a small number of large patches overlying the vegetal pole. We distinguish three processes that produce these changes. The first of these is aggregation which involves the islets moving towards the vegetal pole to form large patches by coalescence. This phase requires microtubules but does not depend on cleavage or dynamic microfilaments. The second phase is ingression during which the patches of germ plasm move to the interior of the egg. The movement is due to a flow of cytoplasm from the vegetal pole internally and the cytoplasmic current does not require either microtubules or dynamic microfilaments. In the third phase, the germ plasm is trapped in the vegetal hemisphere by microtubular arrays--in normal development, the mitotic spindle.


Asunto(s)
Citoplasma/fisiología , Embrión no Mamífero/ultraestructura , Cigoto/ultraestructura , Animales , Microscopía Electrónica , Xenopus
19.
J Anat ; 126(Pt 1): 133-44, 1978 May.
Artículo en Inglés | MEDLINE | ID: mdl-649494

RESUMEN

The intestinal epithelium of feeding Xenopus laevis tadpoles was studied using light microscope, electron microscope and autoradiographic techniques. The wall of the small intestine differs from that of most other vertebrates studied in that it lacks villous-like folds. A single prominent longitudinal fold, the typhlosole, forms about stage 49, and a series of shallow longitudinal epithelial pleats is also present in some animals. The morphology of the epithelial cells indicates that there are no differences between the cells in their degree of specialization. Three epithelial cell types were recognized: principal cells, gland cells and endocrine cells, making up about 65%, 15% and 1%, respectively, of all cells present, while approximately 20% of the cells in the epithelium are lymphocytes, 1% appear to be discharged gland cells, and 2% degenerating cells. No Paneth, caveolated or undifferentiated cells were identified. The findings are discussed in relation to other studies on cell proliferation and on nuclear transplantation.


Asunto(s)
Diferenciación Celular , Intestino Delgado/citología , Xenopus/anatomía & histología , Animales , Anuros , Glándulas Endocrinas/citología , Glándulas Endocrinas/ultraestructura , Células Epiteliales , Epitelio/ultraestructura , Intestino Delgado/ultraestructura , Larva/citología , Linfocitos/ultraestructura , Microscopía Electrónica
20.
J Embryol Exp Morphol ; 34(1): 209-20, 1975 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1237530

RESUMEN

The initial effect of u.v. irradiation of the vegetal pole was to inhibit cleavage in the vegetal hemisphere although karyokinesis was not substantially affected. In this way a syncytium formed in the vegetal hemisphere which broke down into individual cells some time between morula and late blastula. The movement of the germ plasm from the peripheral cortical regions into the interior of the egg was not appreciably delayed although aggregation of the germ plasm did not take place until the individual presumptive primordial germ cells were formed when the syncytium broke down. The method of segregation of the germ plasm and formation of the presumptive primordial germ cells was therefore very different in irradiated embryos from the normal orderly processes which depend on normal cleavage patterns. After neurula, the number of presumptive primordial germ cells declined rapidly and at stage 43/44, when the genital ridges in normal embryos contain primordial germ cells, the genital ridges in irradiated embryos were sterile. These results raise the question whether derangement of the segregation of the presumptive primordial germ cells is solely responsible for the later abnormalities in the cell lineage or whether u.v. irradiation affects the germ plasm and therefore indirectly the germ cells.


Asunto(s)
Células Germinativas/efectos de la radiación , Rayos Ultravioleta , Animales , División Celular/efectos de la radiación , Separación Celular , Embrión no Mamífero/efectos de la radiación , Femenino , Células Germinativas/citología , Mitosis , Óvulo/efectos de la radiación , Efectos de la Radiación , Xenopus
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