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1.
N Engl J Med ; 327(17): 1192-7, 1992 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-1406792

RESUMEN

BACKGROUND: Early diagnosis of human immunodeficiency virus (HIV) infection in infants born to infected mothers is important for the infants' medical care, but the presence of maternal antibodies makes serologic tests uninformative. METHODS: In a cohort study of 181 infants born to HIV-infected mothers, we assessed the diagnostic value of HIV viral culture and testing for the presence of p24 antigen. The infants were tested at birth, again during the first 3 months, then followed and tested at the age of at least 18 months. RESULTS: Of the 181 infants, 3 died of HIV infection and 37 were seropositive after the age of 18 months. Viral cultures at birth were positive in 19 of the 40 infected infants and in none of the uninfected infants, yielding a sensitivity of 48 percent (95 percent confidence interval, 32 to 63 percent) and a specificity of 100 percent (95 percent confidence interval, 97 to 100 percent). By the age of three months, 30 of the 40 infants (75 percent) had positive cultures; again, there were no false positive results among the infants who were tested a second time, of the 141 who remained uninfected. The sensitivity of testing for p24 antigen at birth was only 18 percent, with a specificity of 100 percent. The presence of p24 antigen at birth was associated with the development of early and severe HIV-related disease (P less than 0.04). CONCLUSIONS: Viral culture at birth can correctly identify about half of newborns with HIV infection. The fact that this usually sensitive technique fails to identify about half the ultimately infected neonates suggests that vertical transmission of HIV may occur late in pregnancy or during delivery.


Asunto(s)
Proteína p24 del Núcleo del VIH/análisis , Infecciones por VIH/congénito , Infecciones por VIH/diagnóstico , VIH-1/aislamiento & purificación , Reacciones Falso Negativas , Femenino , Humanos , Lactante , Recién Nacido , Tamizaje Neonatal , Embarazo , Complicaciones Infecciosas del Embarazo , Sensibilidad y Especificidad , Pruebas Serológicas
2.
Hum Reprod ; 4(7): 794-7, 1989 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2606957

RESUMEN

The effects of maternal age on the quality of offspring are well known. Those due to the father's age are less obvious, apart from the role of increasing paternal age in the onset of many dominant autosomal disorders. But an experimental model has demonstrated that, in rats, increasing paternal age, without any other anomalies, might produce a decreased learning capacity in progeny. The object of the epidemiological investigation presented here was to verify whether this effect might also occur in man. The study involved the distribution of scores obtained in psychometric tests by 18-year-old male subjects, according to their father's age at the time of their birth. This distribution indicated not only that increasing paternal age is accompanied by effects similar to those observed in animals, but also that very young paternal age was also related to these effects. Thus, the curve of such scores produced an inverted U-shape, with maximum scores obtained when the father was about thirty years of age. Maternal age did not appear to play a part in this event. These results pose the problem of identifying genetic and/or psychosocial factors which might have an impact on the quality of the conceptus.


Asunto(s)
Aprendizaje , Edad Paterna , Adolescente , Adulto , Humanos , Masculino , Psicometría
3.
Andrologia ; 20(3): 211-7, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3177899

RESUMEN

Human sperm heads which present disturbances of chromatin condensation are stained by acidic aniline, blue. To determine whether the proportion of unstained heads, i.e. with well condensed chromatin, can be considered as an index of sperm quality, a study was undertaken in 157 men during an infertility evaluation. In addition to the usual sperm characteristics, the percentages of unstained heads and of morphologically normal and abnormal forms were concomitantly evaluated. In a total of 15760 spermatozoa, the percentage of unstained heads was much higher in the population of morphologically normal forms than in that of abnormal forms (79.1% and 49.4% respectively, p less than 10(-9]. Among spermatozoa with structural abnormalities, it was much higher in cells with a single anomaly than in those with associated anomalies (53.9% and 40.6% respectively, p less than 10(-9]. When morphology was taken into account, only vitality was found to vary significantly with the percentage of unstained heads.


Asunto(s)
Compuestos de Anilina , Cromatina/análisis , Semen/análisis , Espermatozoides/análisis , Adulto , Colorantes Fluorescentes , Humanos , Masculino , Métodos
6.
Hum Reprod ; 1(4): 255-8, 1986 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3558767

RESUMEN

In a multi-centric study undertaken on 1163 pregnancies obtained by in-vitro fertilization, a 5% risk of ectopic pregnancies was observed. This figure is certainly higher than that admitted for natural reproduction. After simultaneous adjusting for all variables in our data by means of a multiple logistic regression technique, two factors have specific influence: the therapeutic use of clomiphene citrate which increased the rate of ectopic pregnancies from 3 to 6% and the number of patent Fallopian tubes with a change in ectopic pregnancies rate from 3 or 4% (with 0 or 2 patent tubes) to 13% (with one patent tube). These results suggest various physiologic hypotheses as well as therapeutic considerations.


Asunto(s)
Transferencia de Embrión , Fertilización In Vitro , Embarazo Ectópico/etiología , Clomifeno/efectos adversos , Trompas Uterinas/fisiología , Femenino , Humanos , Embarazo , Riesgo
7.
Andrologia ; 18(3): 292-8, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3740484

RESUMEN

A study undertaken on 1345 pregnancies resulting from artificial insemination with donor showed an 18% risk of abortion. This figure is the same as that admitted for natural reproduction. It does not depend on any of the classically studied semen characteristics and in particular remains invariant whatever the postthaw motility, the factor most strongly linked to conception rate. Two results, well known from the literature, i.e. the increased abortion rate mentioned in natural reproduction when the sperm is of poor quality and the high incidence of repeated abortions when sperm quality is particularly good are discussed. The first of these results cannot be considered as being established in a statistically significant way. The second may result from different sources of bias, some of which are identified. In essence a high frequency of abortions signifies simply a high frequency of pregnancies, it is therefore not surprising that the semen is in this case particularly good.


Asunto(s)
Aborto Espontáneo/epidemiología , Inseminación Artificial Heteróloga , Inseminación Artificial , Semen/análisis , Aborto Habitual/epidemiología , Femenino , Francia , Humanos , Masculino , Embarazo , Riesgo , Recuento de Espermatozoides , Motilidad Espermática
8.
Fertil Steril ; 45(2): 255-8, 1986 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3949026

RESUMEN

Among the men who volunteered to become semen donors for artificial insemination at the sperm bank of Centre d'Etude et de Conservation du Sperme Humain, Paris-Bicêtre, some were brothers of the infertile men of couples entering the Artificial Insemination with Donor program. Their sperm characteristics, compared with those of other donor candidates, are clearly lower. The difference is significant for count (78.0 versus 102.8, P less than 0.05) and very significant for the percentage of motile spermatozoa (61.5 versus 66.9, P less than 0.01) and for the percentage of normal forms (51.8 versus 62.7, P less than 0.00001). The differences are even more pronounced when the brothers of azoospermic men are considered. The possibility that some cases of infertility could have a genetic origin is discussed.


Asunto(s)
Infertilidad Masculina/genética , Recuento de Espermatozoides , Motilidad Espermática , Espermatozoides/anomalías , Adulto , Humanos , Inseminación Artificial Heteróloga , Masculino , Oligospermia/genética
9.
Andrologia ; 16(5): 423-8, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6496960

RESUMEN

For the 13 abnormalities under consideration, the mean percentages were found to be the following: irregular head (15.2), microcephalic (9.8), elongated head (5.9), coiled tail (5.8), bent tail (4.7), thin head (4.6), cytoplasmic remains (3.2), macrocephalic (1.6), short tail (1.1), no tail (0.6), duplicate tail (0.5), duplicate head (0.4), lysis (0.4). In so far as the group studied is representative, the results obtained may be considered as "norms" with the 90th percentiles showing the upper limit of the "normal". The same mean percentages were found by MacLeod and Gold (1951) for the five abnormalities they had identified. The length of abstinence preceding the collection of the ejaculate was found to have no influence on the percentage of abnormal forms.


Asunto(s)
Fertilidad , Espermatozoides/anomalías , Factores de Edad , Humanos , Masculino , Abstinencia Sexual , Factores de Tiempo
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