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81.
Follicle stimulating hormone (FSH) is considered to be essential for spermatogenesis. Therefore, genetic abnormalities of FSH signalling on testicular Sertoli cells would be expected to affect sperm production negatively in males. Inactivating FSH receptor mutations have been reported earlier in both males and females. All affected males had elevated FSH serum concentrations and abnormal sperm parameters. We postulated that inactivating FSH receptor mutations might be a cause of oligozoospermia or azoospermia and reviewed the clinical data of 151 male intracytoplasmic sperm injection (ICSI) candidates with special attention to FSH serum concentrations. The exclusion criteria for mutation screening of the FSH receptor gene were: a history of operative sterilization or testicular malignancy, congenital abnormality other than cryptorchidism, and a chromosomal aberration or a Y-chromosome microdeletion. The inclusion criteria were: male (ICSI candidate) with azoospermia or oligoasthenoteratozoospermia (OAT) and elevated FSH serum concentrations. In total, 23 males with OAT and five males with azoospermia were tested for mutations of the coding sequences and the intron-exon boundaries of the FSH receptor gene by polymerase chain reaction (PCR) followed by single strand conformation polymorphism analysis (SSCP). Neutral polymorphisms were readily detected using this technique in both probands and controls. None of the 28 selected patients showed a pathogenic FSH receptor mutation. Mutations in the FSH receptor gene are not a common cause of infertility in ICSI candidates.  相似文献   
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Virus infections have been thought to be involved in the development of childhood leukaemia. In order to address this issue we determined, in a case-control study, the prevalence of antibodies to viruses infecting blood or bone-marrow cells [Epstein-Barr virsus (EBV), human herpes virus type 6 (HHV-6), parvovirus B19] as well as to the human virus known for its tumour-suppressive properties, the adeno-associated virus type 2 (AAV-2), in the sera of 121 children with leukaemia in Germany, and in 197 control individuals, hospitalized for other reasons, and matched for age and gender to the cases. In addition, we developed a questionnaire to be answered by the children's parents, in order to gain information on previous infections of the children as well as to calculate for factors which may influence serological findings. Comparative determination of the prevalence of antibodies against AAV-2, B-19 or HHV-6 revealed no significant differences in cases and controls. However, antibodies to EBV were more frequently found in children with leukaemia younger than 6 years of age (age at the time of diagnosis of leukaemia) than in controls. Apparently, infection with AAV-2 has no protective effect in childhood leukaemia, in contrast to results observed for other malignancies. Similarly, and in accordance with results on leukaemia in adults, we found no indication of a protective effect of infection with the parvovirus B-19. The data suggest that EBV, which is known to be involved in various lymphomas, may play a role in the development of childhood leukaemia in young children.  相似文献   
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The effect of Mycobacterium tuberculosis infection on the viability of healthy (control) human alveolar macrophages was evaluated by staining with ethidium homodimer and calcein to discriminate live from dead cells. Infection with M. tuberculosis H37Ra or H37Rv increased macrophage mortality at 6 days from the control level of 3.8% +/- 0.7% to 28.7% +/- 6.9% or 12.6% +/- 3.1%, respectively (P < 0.001 for comparisons of all conditions). A role for tumor necrosis factor alpha (TNF-alpha) in the M. tuberculosis-induced cytolysis of alveolar macrophages was demonstrated by increased cytotoxicity following the addition of exogenous TNF-alpha to the cultures and by enhancement of macrophage survival when M. tuberculosis-infected alveolar macrophages were treated with pentoxifylline or anti-TNF-alpha antibody. The cytolytic mechanism was determined to be apoptosis by the demonstration of a characteristic internucleosomal ladder of genomic DNA by agarose gel electrophoresis, by finding nuclear fragmentation and condensation by electron microscopy, and by in situ terminal transferase-mediated nick end labeling of fragmented DNA in alveolar macrophages infected with M. tuberculosis in vitro. The latter technique was employed to reveal extensive apoptosis within caseating granulomas from lung tissue samples from clinical tuberculosis cases. The induction of apoptosis in alveolar macrophages by M. tuberculosis may play a role in the macrophage-pathogen interaction of tuberculosis in vivo.  相似文献   
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OBJECTIVES: To investigate the changes in the cholesterol:phospholipids (C/PL) ratio of erythrocyte membrane in post-menopausal women with and without hormone replacement therapy (HRT). STUDY DESIGN: A cross-sectional study including 83 patients divided into three groups according to HRT (group 1, no HRT (n = 52); group 2, combined HRT (n = 16); and group 3, estrogen-only therapy (n = 15)). RESULTS: The C/PL ratio was lower in group 2 with respect to group 1 and group 3 (P = 0.03). No difference was found in erythrocyte membrane cholesterol between the three groups; however, the phospholipid concentration was higher in group 2 with respect to the other groups (P < 0.05). In the control group, C/PL values correlated positively with plasma LDL levels (P < 0.005) and negatively with HDL levels (P < 0.005). CONCLUSIONS: From our data the addition of progestogens in HRT appears to decrease the C/PL of the erythrocyte membrane possibly resulting in a beneficial effect on rheological properties of erythrocyte membrane. The results of our study thus suggest additional benefits from supplementation of progestogens in HRT, in addition to prevention of estrogen dependent endometrial hyperplasia and adenocarcinoma.  相似文献   
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OBJECTIVES: To compare the differences in correlates of different levels of depression in medically ill hospitalized older adults. DESIGN, SETTING, AND PARTICIPANTS: A consecutive series of 542 patients aged 60 or older admitted to the medical inpatient services of Duke Hospital underwent a structured psychiatric evaluation administered by a psychiatrist. MEASUREMENT: A wide range of demographic, social, psychiatric, and physical health data were collected, and associations with major and minor depression were assessed. RESULTS: Compared with patients without depression, those with major depression were more likely to have a history of prior episodes of depression, higher dysfunctional attitude scores, greater overall severity of medical illness, cognitive impairment, and symptoms of pain or other somatic complaints. Specific medical diagnosis was less important a predictor of major depression than overall severity of medical illness. Compared with patients without depression, those with minor depression were more likely to report non-health-related stressors during the year before hospital admission, have a diagnosis of immune system disorder, and have greater severity of medical illness. When major and minor depression were compared directly, on the other hand, no significant differences were observed except for history of depression, and that relationship was weak and present only when the etiologic approach to diagnosis was used. CONCLUSION: During hospital admission, certain psychosocial, psychiatric, and physical health characteristics of older medical patients place them at high risk for different levels of depression. Patients with major and minor depression resemble each other more than they do patients without depression. These findings may help clinicians better understand the causes of different types of depression in this setting and lead to improved diagnosis and treatment.  相似文献   
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