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21.
22.
By the end of 1990, 51 symptomatic children with perinatally acquired HIV infection had been admitted to Baragwanath Hospital. Of 42 children who were followed up for at least 3 months, 15 (35.7%) died and 16 (38.1%) were lost to follow-up. The case fatality rate for these children lies between 35.7% and 73.8%. Most children became symptomatic before the age of 6 months and presenting features seen in over 70% of cases included lymphadenopathy, failure to thrive and hepatomegaly. Surviving children had recurrent admissions to hospital, predominantly for respiratory distress. Many had bacterial pneumonias. Cardiac involvement (cardiomyopathy and cor pulmonale), recurrent serious bacterial infections and neurodevelopmental abnormalities were common. Our experience confirms that vertically acquired HIV infection has a relatively short incubation period and progresses rapidly with cardiorespiratory symptoms predominating. Five HIV seroprevalence studies have been conducted in pregnant women attending Baragwanath Hospital and the Soweto clinics since 1988. The calculated doubling time is between 7 and 21 months. At the end of 1990 the HIV seroprevalence rate in pregnant women was 0.82% (95% confidence limits 0.44-1.19%). 相似文献
23.
Lynn McIntyre Edwin G. Belzer Lise Manchester Wade Blanchard Suzanne Officer A. Catherine Simpson 《The Journal of school health》1996,66(3):132-137
ABSTRACT: The Dartmouth Health Promotion Study was a longitudinal, quasi-experimental field study with a qualitative research arm, designed to learn whether coordinating school health instruction, health services, and a healthful environment enhanced the program's effect on the heart health and mental health of children. The research strategy — the Coordinated Approach — was applied to approximately 300 children in each of two cohorts in grades four to six attending nine trial schools; a further 600 children attended 10 comparison schools in Dartmouth and nine distal comparison schools. Although the qualitative analysis demonstrated that positive feelings were engendered in most areas of the study, when either the classroom or the individual was used as the unit of analysis, the Coordinated Approach did not have a more favorable effect on the heart or mental health of children than did the standard school health program. Thus, the effect of an existing school health program was not directly enhanced through coordinating its components. 相似文献
24.
Anderson RA; Evans LW; Irvine DS; McIntyre MA; Groome NP; Riley SC 《Human reproduction (Oxford, England)》1998,13(12):3319-3325
Follistatin is a binding protein for the activin and inhibin family of
hormones, regulating their biological activity. In the male reproductive
tract, the interaction of these factors is likely to be involved in the
regulation of the proliferation of several cell types. We have investigated
the presence of follistatin and activin A in seminal plasma using specific
immunoassays and have localized follistatin and activin/inhibin subunits in
the adult human testis, prostate and seminal vesicle to establish their
likely sources. High concentrations of immunoreactive follistatin were
present in seminal plasma in normal men (mean 97.9 ng/ml; 1.43 ng/ml in
peripheral plasma) and were similar in men with oligo/azoospermia and
following vasectomy. Follistatin immunoreactivity was localized to both
Leydig and Sertoli cells of the testis, and to epithelial cells of the
prostate gland and seminal vesicle, which are likely to be the predominant
sources of the hormone in seminal plasma. Activin A was also present in
seminal plasma in normal men but was undetectable following vasectomy, thus
deriving from the testis. Consistent with this finding, the betaA-subunit
was immunolocalized in Sertoli and Leydig cells but was not present in
seminal vesicle or prostate gland. The functional significance of the high
concentrations of follistatin secreted into seminal plasma by the prostate
gland and/or seminal vesicle is uncertain, but they may regulate the
biological activity of testis-derived activin A and inhibin B.
相似文献
25.
The diagnosis and management of ascites related to liver diseases is discussed. We emphasize that although treating ascites improves the symptoms, it does not influence prognosis, whereas injudicious treatment may cause life-threatening side effects. 相似文献
26.
Periosteal Ewing sarcoma 总被引:3,自引:0,他引:3
27.
28.
In a prospective, randomized study of insemination with donor semen,
intracervical insemination by straw was compared with insemination using a
cervical cap with an intracervical reservoir. A total of 91 patients
completed 486 treatment cycles. There were no significant differences in
age, parity, indication for insemination by donor, or method of cycle
monitoring between women who became pregnant and those who did not conceive
with either insemination method. In 236 standard intracervical insemination
cycles, 14 patients became pregnant (5.9% per cycle), whereas 38 patients
conceived in 250 cervical cap cycles (15.2% per cycle). Both the crude
pregnancy rates and the cumulative pregnancy rates calculated by the
Kaplan-Meier life-table method were significantly different (chi(2)-test, P
< 0.001, and log-rank test, P < 0.005 respectively). Pregnancy rates
in artificial insemination with cryopreserved donor semen may be improved
by the use of a cervical cap when compared to cervical insemination by
straw. The use of the cervical cap may prolong the exposure of the
spermatozoa to the cervical mucus and prevent the backflow of semen into
the vagina.
相似文献
29.
30.
Meniscal abnormalities: prospective correlation of double-contrast arthrography and arthroscopy 总被引:2,自引:0,他引:2
In a prospective study conducted over a 12-month period, 30 patients underwent double-contrast arthrography of the knee followed by arthroscopic study. An 80% correlation rate was found between results. Arthrography had a higher rate of accuracy (93%) than arthroscopy (84%) and had a 7% false-positive and 0% false-negative rate. A commonly overlooked arthrographic sign--the triple-S or stuck sail sign--was 91% accurate in the prediction of meniscal tears. The complementary nature of the two examinations is discussed. 相似文献