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981.
The clinical features of the Marcus Gunn (jaw-winking) phenomenon are described and a case is reported in a 23-year-old female who also had congenital left duplex kidneys and ureters.  相似文献   
982.
In a cross-sectional study of 926 subjects from 10 drug treatment programs conducted in 1984 in New Jersey, the seroprevalence of human immunodeficiency virus (HIV) was 35% overall; 30% in whites, 33% in hispanics, and 46% in blacks (p = 0.01 for comparison of blacks to non-blacks). Univariate analysis showed the seroprevalence of HIV was not associated with age or gender, but did correlate with frequency of cocaine or heroin injection (p trend less than 0.001); frequency of needle sharing (p trend = 0.007); and inversely with levels of education (p = 0.05). The prevalence of HIV was also inversely related to the distance of the treatment center from lower Manhattan; being highest for distances of less than 5 miles from lower Manhattan and lowest for distances of 80 miles, with intermediate rates for the intervening distances (p trend less than 0.001). In multivariate analyses, HIV seropositivity was consistently associated with the frequency of needle sharing (p = 0.02) and less than 12 years (high school level) of education (p = 0.02), but not with black race. However, blacks who shared needles less than once a month had a relative risk of 3.2 (95% CI 1.2, 7.7) while non-blacks who shared less than once a month had a relative risk of only 0.9 (95% CI 0.3, 2.4). The risk in non-blacks increased to more than twofold with more frequent needle sharing. When the analysis was stratified by gender and adjusted for needle sharing and geography, a significant twofold increased risk was observed for female (but not male) subjects who had two or more heterosexual partners compared with those who had one partner.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
983.
This is a case report of a low-grade leiomyosarcoma of the bladder in a four-year-old girl. The pitfalls in diagnosing a soft tissue tumor of the bladder in pediatric patients are discussed. This case is particularly instructive because the differential diagnosis was broad, difficult, and of serious consequence. This report discusses the process by which histologic, immunohistologic and ultrastructural data were used to sidestep the pitfalls in diagnosing this unusual tumor. Clinical follow-up data bearing out our conclusion are also presented.  相似文献   
984.
The gene for the catalytic RNA subunit of RNase P has been isolated from several Enterobacteriaceae by complementation of an Escherichia coli strain that is temperature-sensitive for RNase P activity. The selection procedure relies on the ability of the heterologous gene products to function enzymatically in E. coli. This procedure obviates the need for positive results in DNA blot hybridization experiments or for the purification of holoenzyme to identify the RNA component of RNase P and its corresponding gene from organisms other than E. coli. Comparisons of the variations in sequences provide the basis for a refined two-dimensional model of the secondary structure of M1 RNA.  相似文献   
985.
986.
The treatment of adult patients greater than 55 to 70 years of age with acute myelogenous leukemia (AML) is associated with a treatment-related mortality of approximately 25%. This prospective, double-blind randomized study was designed to see if the use of granulocyte- macrophage colony stimulating factor (GM-CSF; yeast-derived) could shorten the period of neutropenia and to determine any effect this would have on therapy-related morbidity and mortality. A total of 124 patients entered this study. Induction consisted of standard daunorubicin and cytarabine. A day-10 bone marrow was examined; if this was aplastic without leukemia, patients received blinded placebo or GM- CSF from day 11 until neutrophil recovery. Patients who entered complete remission received the identical study medication (blinded GM- CSF or placebo) in consolidation that they had received during induction. The overall complete remission rate was 52%; 60% for the GM- CSF arm and 44% for the placebo arm (P = .08). Median times to neutrophil recovery were significantly shortened on the GM-CSF arm. The overall treatment-related toxicity from start of GM-CSF/placebo was reduced on the GM-CSF arm (P = .049). Similarly, the infectious toxicity was significantly reduced on the GM-CSF arm (P = .015). The median survival for all patients was 10.6 months in the GM-CSF group and 4.8 months in the placebo arm (P = .048). It appears that GM-CSF is safe and efficacious for adult patients greater than 55 to 70 years of age with AML; its major impact is in reducing the duration of neutropenia and therapy-related mortality and morbidity. This may result in a better response rate.  相似文献   
987.
红参中多肽成分的分离和鉴定   总被引:6,自引:0,他引:6  
本文报道用反相高效液相色谱技术,自红参中分得两个新的多肷类化合物。根据氨基酸组成分析和分子量测定结果,鉴定为13肽和15肽。文中还应用组织培养技术,研究了红参多肽的活性。  相似文献   
988.
Kaye  JJ 《Radiology》1985,157(1):265-266
Three recent studies on intraarticular knee structures are considered-one on an advance in conventional knee arthrography and two on use of computed tomography in evaluating knee menisci. A resurgence of knee arthrography is predicted.  相似文献   
989.
990.
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