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61.
The CYP11A gene encodes the cholesterol side-chain cleavage enzyme (P450scc) that catalyzes the first and rate-limiting step for the biosynthesis of sex hormones. A pentanucleotide repeat [(TAAAA)n] polymorphism in the 5' of the CYP11A gene has been reported to be related to the risk of polycystic ovary syndrome, an inherited endocrine disorder characterized by hyperandrogenemia. We investigated the association of this polymorphism with breast cancer risk in a population-based case-control study conducted among Chinese women in Shanghai. Genotype assays were completed for 1015 incident breast cancer cases and 1082 community controls. Three common alleles with 4, 6, or 8 TAAAA repeats were identified in the study population. The frequency of the 8 repeat allele was more common in cases (12.6%) than controls (8.5%) (odds ratio = 1.6, 95% confidence interval = 1.3-1.9; P < 0.0001). Compared to subjects who did not carry this allele, adjusted odds ratios were 1.5 (95% confidence interval = 1.2-1.9) and 2.9 (1.3-6.7) (P for trend, <0.001), respectively, for those who carried one and two copies of this allele. This positive association was observed in both pre- and postmenopausal women and all strata defined by major breast cancer risk factors, including years of menstruation, body mass index, and waist-to-hip ratio. The results from this study indicate that the TAAAA repeat polymorphism near the promoter region of the CYP11A gene may be an important susceptibility factor for breast cancer risk.  相似文献   
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64.
Increase of hepatocyte growth factor after renal transplantation   总被引:2,自引:0,他引:2  
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65.
Immune inner ear disease results in rapidly progressive, bilateral sensorineural hearing loss and is one of the few forms of sensorineural hearing loss that can be treated medically. The purpose of this study is to identify and preserve several populations of sensitized lymphocytes from patients with immune inner ear disease as a first step toward cloning autoreactive T cells, in order to study the pathogenesis of disease. Lymphocytes from four patients with high reactivity (stimulation index of 2.5 or greater) were placed in frozen storage. At 8 to 14 months they were thawed and restimulated. All four samples were viable. Two reacted again to inner ear homogenate, but with different intensities. Some lymphocytes sensitized to inner ear antigens can retain reactivity after frozen storage. This methodology may be useful to clone highly reactive T cells.  相似文献   
66.
The objective of this study was to examine the effects of the intakeof dietary fat upon colorectal cancer risk in a combined analysis of datafrom 13 case-control studies previously conducted in populations withdiffering colorectal cancer rates and dietary practices. Original datarecords for 5,287 cases of colorectal cancer and 10,470 controls werecombined. Logistic regression analysis was used to estimate odds ratios (OR)for intakes of total energy, total fat and its components, and cholesterol.Positive associations with energy intake were observed for 11 of the 13studies. However, there was little, if any, evidence of anyenergy-independent effect of either total fat with ORs of 1.00, 0.95, 1.01,1.02, and 0.92 for quintiles of residuals of total fat intake (P trend =0.67) or for saturated fat with ORs of 1.00, 1.08, 1.06, 1.21, and 1.06 (Ptrend = 0.39). The analysis suggests that, among these case-control studies,there is no energy-independent association between dietary fat intake andrisk of colorectal cancer. It also suggests that simple substitution of fatby other sources of calories is unlikely to reduce meaningfully the risk ofcolorectal cancer.  相似文献   
67.
大肠癌防治现场研究   总被引:10,自引:1,他引:10  
郑树 《中国肿瘤》2005,14(6):352-354
大肠癌在我国近几年发病率上升,5年生存率在60%左右,但治疗效果30年来无显著提高.20世纪70年代以来,浙江大学肿瘤研究所课题组负责大肠癌防治"六五"、"七五"、"八五"及"九五"攻关研究,历时二十余年,进行了从现场到实验室,从病因机制到干预阻断的系列研究.  相似文献   
68.
Pathologic accumulation of neurofilament protein (NF), both within spheroids of the proximal axon and within inclusions of motor neuron somata, is a hallmark of neurodegeneration in amyotrophic lateral sclerosis (ALS). Transgenic mice that express mutations in superoxide dismutase (SOD-1), which were genetically linked to familial ALS, develop symptomatology and pathology that strongly resemble ALS and therefore provide a useful model for studying the disease. Examining NF in the G86R mutant SOD-1 transgenic mice, we previously demonstrated that phosphorylated NF accumulates in motor neuron somata of symptomatic transgenic mice. In the present study, we expand these results by examining the immunocytochemical distribution of the three subunits of NF (i.e., light, medium, and heavy chains) as well as tubulin in presymptomatic and symptomatic SOD-1 transgenic mice. Although all NF subunits, but not tubulin, accumulate along with phosphorylated NF in the spinal cord inclusions of symptomatic mice, numerous inclusions containing only light chain NF are found in the spinal cord of presymptomatic SOD-1 transgenic mice. In addition to these results in the spinal cord, intensely immunoreactive aggregates of NF-L, but not the other NF subunits or tubulin, were observed in the sciatic nerve of both symptomatic and presymptomatic mutant SOD-1 transgenic mice. These results suggest that the mechanism of NF alteration in SOD-1 transgenic mice, and also perhaps in ALS patients, originates with the disruption of NF-L, only later involving the other subunits.  相似文献   
69.
非凝固手术联合氪多波长激光治疗单纯孔源性视网膜脱离   总被引:1,自引:0,他引:1  
目的:探讨将巩膜扣带术中冷凝改为术后氪多波长激光光凝封闭裂孔治疗视网膜脱离的疗效、适应证范围及临床意义。方法:回顾性分析2001/2003在我院行非凝固巩膜扣带手术联合术后氪多波长激光封闭裂孔治疗孔源性视网膜脱离36例(36眼),观察其疗效并对结果进行评价。结果:术后随访3-24mo,视网膜完全复位的32例,术后0.5a后矫正视力≥0.132例,最佳矫正视力为1.5。结论:非凝固巩膜扣带术联合氪多波长激光治疗单纯孔源性视网膜脱离,简化了手术操作,无凝固手术相关的并发症,术后采用氪多波长激光封闭裂孔,可以根据裂孔的部位及届光介质混浊的程度选用不同波长的激光进行封孔,是治疗单纯孔源性视网膜脱离的有效方法之一。  相似文献   
70.
重度妊高征并发腹水48例临床分析   总被引:13,自引:0,他引:13  
目的 :分析重度妊娠高血压综合征 (简称妊高征 )并发腹水的临床特点和防治方法。方法 :将我院 1996年 1月~ 2 0 0 2年 12月间 2 0 4例重度妊高征分为并发腹水组 (A组 ,4 8例 )和未并发腹水组 (B组 ,15 6例 ) ,比较其临床特点。结果 :A、B两组间比较 ,终止妊娠的时间、肝功能检查总蛋白、白蛋白、白 /球比值、乳酸脱氢酶、血肌酐、2 4小时尿蛋白定量、宫内死胎发生率、新生儿早产发生率、孕产妇并发症的发生率差异有显著性 (P <0 .0 5 )。结论 :重度妊娠高血压综合征并发腹水病情极为严重 ,应及时终止妊娠 ,分娩后腹水可消退 ;早期、系统、定期的产前检查可及时发现、预防重度妊高征及并发症的发生。  相似文献   
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