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Twin pregnancies have higher perinatal morbidity and mortality rates than singleton pregnancies. Researchers have demonstrated that one major benefit of prenatal care in the twin gestation is reduced fetal death rate. This study to determine the relationship of nonstress tests (NSTs) to pregnancy outcome in twin gestations comprised 665 women who delivered at Los Angeles County-University of Southern California Women's Hospital from January 1985 to January 1989. These patients, all of whom had prenatal care (PNC), were subdivided into two groups: (1) PNC and NSTs and (2) PNC and no NSTs. The groups did not differ statistically with regard to gravidity, parity and abortions. NSTs were selectively done on twin gestations complicated by discordancy or other fetal/maternal complications. Ten pregnancies were complicated by fetal demise of one or both twins in patients who received prenatal care without NSTs. Among the NST group there was one fetal demise. Although the NST group had fewer fetal deaths, the reduction was not statistically significant (P = .062). Infant birth weight was identified as a confounder because the NST group had a statistically higher mean birth weight. Definitive proof of the ability of NSTs to reduce the fetal death rate in twin gestations complicated by discordancy or other pregnancy complications awaits a large, prospective, randomized trial.  相似文献   
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Fifteen patients with advanced head and neck cancer not curable with radiation or surgery were entered into a phase II study of 10-EdAM. None of the patients had received prior chemotherapy. 10-EdAM was administered intravenously at a dose of 80 mg/m2 each week. Four patients were not eligible for evaluation. Two died before completing four cycles of chemotherapy, one refused further treatment and one developed hepatic toxicity resulting in withdrawal. Of the remaining patients, three had a partial response. The major toxicities were leukopenia and mucositis.  相似文献   
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Although tissues in the case series of anal, penile, vaginal and vulvar neoplasms that have looked for evidence of HPV infection by probing for HPV DNA have been selected for convenience, they support the view that HPV, especially type 16, is associated with approximately 50% of these tumours. A higher percentage of the anal, vaginal and vulvar tumours are associated with HPV 16 than are penile tumours. This discrepancy may be due to the low number of penile tumours studied or to a true difference in the proportion of penile cancer cases related to HPV. HPV 6/11 and 18 are found less frequently at all anatomic sites. About 10% of tumours that are probed for these viruses are positive, although there are some notable exceptions such as a study that found 39% of penile tumours positive for type 18 and a study that found approximately two thirds of vulvar tumours positive for HPV 18 using Southern blot hybridization. For all of these tumours, there is likely to be a subset of the cases who develop their cancer through mechanisms that do not involve HPV. The case-control studies found a strong association with genital warts, number of sexual partners and, with the exception of vaginal cancer, smoking and/or heavy smoking at the time of diagnosis of the disease. A history of genital warts, smoking at diagnosis, and seropositivity to HSV2 are exposures that have also been found to be associated with cervical cancer. A population-based case-control study in western Washington and Vancouver, British Columbia that studied all anogenital cancers found that a history of genital warts was stronger among patients with vulvar, anal, vaginal and penile cancer than among those with cervical cancer. This was also true of smoking at diagnosis, with the exception of vaginal cancer, where there was little excess risk. This study and other supporting data indicate that these anogenital tumours share many of the same risk factors as cervical cancer.  相似文献   
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To study the projection from the pretectum to the lateral geniculate nucleus, we placed wheat-germ agglutinin conjugated to horseradish peroxidase into the lateral geniculate nuclei of six cats, allowed this marker to be retrogradely transported by afferent axons to their parent somata in the pretectum, and revealed the label in these cells with stabilized tetramethylbenzidine histochemistry. In three cases we made large pressure injections that completely infiltrated the lateral geniculate nucleus and extended into neighboring thalamic nuclei; in the other three we made smaller iontophoretic injections largely confined to the A- and C-laminae of the lateral geniculate nucleus. In both types of injection we found labeled pretectal cells mainly in the nucleus of the optic tract but also found some cells labeled in the olivary pretectal nucleus and the posterior pretectal nucleus. After one of the larger injections we analysed both sides of the pretectum and found that 11% of the labeled cells were located contralaterally and were distributed in the same three nuclei. We analysed only the ipsilateral side in the remaining five cats. In those five experiments we also immunohistochemically stained the pretectal sections with an antibody directed against the neurotransmitter, GABA. Of the retrogradely labeled pretectal cells, 40% were also labeled for GABA, and those were similar in soma size (350 microns 2 in cross-sectional area) to those labeled only with the retrograde marker (331 microns 2). GABA-positive cells not labeled by retrograde transport were smaller (246 microns 2) than either of these other cells populations. These results indicate that at least 40% of the cells involved in the projection from the pretectum to the lateral geniculate nucleus are GABAergic. We suggest that this extrathalamic projection may serve to inhibit thalamic GABAergic cells. This, in turn, would disinhibit geniculate relay cells, thereby facilitating the geniculate relay of retinal information to cortex.  相似文献   
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