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991.
PURPOSE: We studied the relation of breast cancer to common deletion mutations in GSTM1 and GSTT1 and the functional Ile(105)Val polymorphism in GSTP1 in a large, population-based case-control study conducted in China and performed a meta-analysis to summarize the literature. EXPERIMENTAL DESIGN: In the case-control study, a total of 1144 breast cancer cases and 1221 community controls were genotyped for GSTM1, GSTP1, and GSTT1 using PCR-based methods. Associations of genotypes and breast cancer were evaluated in logistic regression models. Meta-analysis odds ratios (ORs) were estimated using a fixed effects model. RESULTS: In the case-control study, associations were null for GSTM1 [age-adjusted OR 0.97, 95% confidence interval (CI): 0.82-1.14] and GSTT1 (OR 0.97, 95% CI: 0.83-1.15). A significant increase in risk was observed among homozygotes for the variant Ile(105)Val polymorphism (OR 1.92, 95% CI: 1.21-3.04). No combined effects of GSTM1, GSTP1, and GSTT1 genotypes or interactions with potential effect modifiers were detected. All results were similar in pre- and postmenopausal women and for early versus advanced stage breast cancer. The meta-analysis, based predominantly on Caucasian women, supported null results for the homozygous deletion variant in GSTM1 (summary OR 1.05; combining 19 studies) and GSTT1 (summary OR 1.11; 15 studies). Meta-analysis results for the homozygous GSTP1 variant indicated no overall association (summary OR 1.04; 10 studies), although results varied significantly across studies (P = 0.009). CONCLUSIONS: This large case-control study provides strong support for earlier studies showing no overall association of the GSTM1 and GSTT1 deletion polymorphisms with breast cancer risk. The GSTP1 variant may be relevant to breast cancer risk in Asian populations.  相似文献   
992.
993.
Objective: To evaluate the diagnostic implications of immunohistochemieal markers in uterine smooth muscle tumors. Methods: Formalin-fixed paraffin-embedded tissue blocks were selected from 17 uterine leiomyosarcomas, 40 uterine unusual leiomyomas and 25 uterine usual leiomyomas. Utilizing immunohistochemical techniques with antigen retrieval, serial sections of each tumor for immunoreactivity with myogenic markers, ovarian steroid receptors, CD44v3, proliferating cell nuclear antigen and mast cells were assessed. Results: Although the myogenic markers and CD44v3 showed less frequent positivity in uterine leiomyosarcomas than those in unusual leiomyomas,they were not reliable markers for differentiating leiomyosarcoma from leiomyoma. Uterine leiomyosarcoma tended to have lower ovarian steroid receptors immunoreactivity rates than leiomyoma. Leiomyoma tended to have a higher quantity of intratumoral mast cells than leiomyosarcoma, while the expression of proliferating cell nuclear antigen was lower in them. Conclusion: Because the estimation of mitotic count was subject to significant variation, the immunohistochemical expression of ovarian steroid receptors, mast cells and proliferating cell nuclear antigen seemed to be helpful for the discrimination of unusual leiomyoma from leiomyosarcoma.  相似文献   
994.
BACKGROUND: We used a murine model of orthotopic corneal transplantation to determine whether host deficiency in ICAM-1 promotes survival of corneal grafts with different degrees of allodisparity. METHODS: ICAM-1-/- and wild-type C57BL/6 (ICAM-1+/+) received corneal grafts from the following strains of mice: BALB/c (fully mismatched), BALB.b (mismatched at multiple minor H only), or B10.D2 [including major histocompatibility complex (MHC) mismatch]. Graft rejection, induction of allospecific delayed-type hypersensitivity (DTH) responses, and leukocytic infiltration of grafts were measured. RESULTS: There were no differences in long-term survival of allografts that were either fully mismatched or had only minor H disparity in ICAM-1+/+ vs. ICAM-1-/-hosts. However, whereas B10.D2 grafts were accepted in only 58% of the ICAM-1+/+ hosts, graft survival in ICAM-1-/- recipients was 100% (P=0.006). Moreover, none of the ICAM-1-/- mice receiving B10.D2 grafts developed allospecific DTH. CONCLUSIONS: Prolonged survival seen in MHC-mismatched grafts in ICAM-1-/- mice, along with a suppressed DTH response to donor alloantigens after transplantation, suggest that ICAM-1 is associated with recipient sensitization to MHC alloantigens.  相似文献   
995.
嗜铬细胞瘤临床诊治   总被引:16,自引:1,他引:15  
Zhu Y  Wu Y  Liu D  Sun F 《中华外科杂志》2000,38(11):852-854
目的 提高嗜铬细胞瘤的诊治水平。方法 总结1958年至1998年间经手术和病理证实的嗜铬细胞瘤286例。结果 本组220例患者肿瘤位于肾上腺,66例位于肾上腺外。在29例恶性嗜铬细胞瘤中,7例位于肾上腺,22例位于肾上腺外。19例为静止型嗜铬细胞瘤。手术切除肿瘤281例。结论 对潜在的儿茶酚胺性心肌病的防治可降低手术死亡率。恶性嗜铬细胞瘤的诊断要靠长期严密的随访。  相似文献   
996.
心外管道全腔肺动脉吻合术的临床应用   总被引:8,自引:1,他引:7  
Wu Q  Chu J  Zhu J  Liu P  Zhang H 《中华外科杂志》2000,38(11):847-849
目的 评价心外管道全腔肺动脉吻合术的临床应用价值。方法 1998年6月~1999年8月,10例先天性心脏复杂畸形的患者接受了心外管道全腔肺动脉吻合术。包括单心室8例,均伴有完全性大动脉转位;右心室发育不良2例。均在全麻低温体外循环下手术。结果 患者全部治愈出院。术后随访6~18个月,无晚期死亡。所有患者症状消失,无静脉压明显升高现象,超声检查显示心外管道血流通畅,无血栓形成;心电图检查显示无严重心  相似文献   
997.
Purpose: To observe the clinical therapeutic effect in the treatment of enuresis by ginger-partitioned moxibustion plus cupping therapy.Methods: Ginger-partitioned moxibustion was applied on Guanyuan (CV 4) and bilateral Zusanli (ST 36) and cupping therapy was applied on Shenque (CV 8) in the treatment of 82 cases of enuresis, in comparison with 76 cases treated by Chinese herbal medicine.Results: The effective rate was 84.1% in the treatment by ginger-partitioned moxibustion plus cupping therapy and was 64.5% in the treatment by Chinese herbal medicine.Conclusion: Ginger-partitioned moxibustion plus cupping therapy was better than Chinese herbal medicine in the treatment of enuresis (P<0.05). Translator: HUANG Guo-qi  相似文献   
998.
Huang X  Wang X  Zhu J  Hou S  Dong J 《中华外科杂志》2000,38(3):226-228
目的 观察化学药物大鼠多发肾囊肿伴肾肿瘤模型的诱发情况和DNA损伤标记物8-羟基脱氧鸟苷(8-OHdG)在其肾组织的表达。方法 用2-氨基4,5-二苯噻唑(DPT)和N-亚硝基吗啉(NNM)诱发和人类获得性肾囊肿(ACDK)伴肾癌相似的大鼠动物模型,并用免疫组化方法(LSAB法)检查8-OHdG在大鼠肾组织的表达。结果在本实验中,NNM组3/10的大鼠诱发肾肿瘤出现,在DPT/NNM组的9只大鼠均  相似文献   
999.
Zhu J  Chen L  Leng X  Du R 《中华外科杂志》2000,38(5):325-328
目的 探讨肝硬化门静脉高压症患者肝脏组织α1肾上腺素受体亚型mRNA的表达。方法 应用半定量逆转录聚合酶链反应检测了12例乙型肝炎后肝硬化门静脉高压症患者和15例无高血压,无肝脏疾患的胆石症或胃肠道肿瘤患者肝脏组织α1肾上腺素受体亚型mRNA的表达。在同一体系中同时逆转录并扩增α1肾上腺素受体亚型特异性片段和内参GAPDH片段,以二者的积分密度比值作为该受体亚型的mRNA相对表达量。结果 肝脏组织  相似文献   
1000.
PURPOSE: Multiple chromosome abnormalities, including gain of chromosome20q, have been detected frequently in human pancreatic cancers. Overexpression of the STK15/BTAK/Aurora A gene located on chromosome 20q13, which encodes a centrosome-associated serine/threonine kinase, has been shown to induce chromosomal instability, leading to aneuploidy and cell transformation in multiple in vitro experimental systems. The purpose of this study was to investigate the expression and copy number alteration of STK15 in pancreatic cancer. EXPERIMENTAL DESIGN: STK15 expression at both the mRNA and protein levels together with the copy number of STK15 gene was measured in nine pancreatic carcinoma cell lines: (a) HPAF-II; (b) Aspc-1; (c) Panc-1; (d) Panc-3; (e) Panc-28; (f) Panc-48; (g) HS766T; (h) MIAPaCa-2; and (i) BxPc3. STK15 protein expression was also examined in normal pancreatic tissues and tumors by Western blotting and immunohistochemistry. RESULTS: STK15 was overexpressed in all of the nine cell lines examined, but gene amplification was infrequent. Western Blot analysis of primary tumor tissues revealed 2-10 times overexpression of STK15 protein compared with normal adjacent tissues from pancreatic cancer patients. Concurrent overexpression of cdc20, an STK15-associated protein, and reduced expression of cdc25, a mitosis-activating protein phosphatase, were detected in the same tumor samples. Elevated STK15 protein expression was detected in 22 of 38 tumor sections (58%) from pancreatic cancer patients. The extent of STK15 expression was not significantly correlated with the size, degree of differentiation, and metastasis status of the tumors. CONCLUSIONS: These results show that STK15 is overexpressed in pancreatic tumors and carcinoma cell lines and suggest that overexpression of STK15 may play a role in pancreatic carcinogenesis.  相似文献   
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