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101.
目的:观察肝癌形成过程中明胶酶表达(蛋白及mRNA水平)的动态变化,探索明胶酶在肝癌生长浸润中的作用。方法:应用免疫组化法、明胶酶谱法和RT-PCR法对大鼠肝癌形成过程中各期明胶酶表达情况进行观察,并与正常对照组进行比较分析。结果:正常肝组织及肝硬化组织内明胶酶有表达,肝癌形成后主要在癌细胞内表达;明胶酶原在正常肝组织中有低表达,诱癌过程中呈持续增高趋势;明胶酶-2mRNA与其酶蛋白表达趋向一致。结论:在肝癌形成过程中明胶酶转录和翻译水平均呈持续增高趋势。  相似文献   
102.
目的 探讨旋磁场与大面积静磁场对置对胆结石病人胆汁中总胆红素(BIT)、直接胆红素(BID)、间接胆红素(BII)、钙(Ca)、胆固醇(CH)和pH的影响。方法 旋磁组30例,测定旋磁处理前后65对胆汁样本。空白对照组15例,留取前后30对胆汁样本。将直径12mm圆形稀土永磁片110块,表面磁感应强度210mT,分别间隔10mm贴于210mm×220mm铁皮上形成一个大面积磁板与旋磁头表面静磁感应强度160mT,旋转平均表面磁感应强度100mT呈异名极对置,磁板置肝区背侧,旋磁头置剑突下处理40min。结果 旋磁组胆结石病人胆汁(n=65):经旋磁场与磁板对置处理前减去处理后差值的x±s和t值分别为BIT41.81±93.52、3.59;BID 13.57±43.70、2.46;BII28.27±61.67、3.32;Ca 0.19±0.31、4.87;CH0.12±0.29、3.36;pH 0.01±0.27、0.30。除pH外,其余各项指标P值均<0.05。对照组胆汁(n=30):间隔时间前后差值的x±s和t值分别为BIT4.42±22.05、1.14;BID2.40±12.37、1.06;BII2.52±46.27、0.30;Ca0.01±0.18、0.50;CH0.03±0.15、0.94;pH 0.009±0.06、0.84。P值均>0.05。结论 在本项磁场类型、强度和时间处理条件下,旋磁场与磁板对置能明显影响胆结石病人胆汁中的BIT、BID、BII、Ca和CH的浓度变化,且有显著降低的作用。  相似文献   
103.
目的 构建大鼠MMP1 3重组腺病毒载体。方法 将MMP1 3cDNA目的片段插入腺病毒柯氏质粒中 ,再将此质粒与腺病毒DNA末端蛋白复合物共转染 2 93细胞 ,通过同源重组构建MMP1 3 重组腺病毒载体。结果 MMP1 3 重组腺病毒载体经PCR鉴定正确 ,包装纯化后 ,检测病毒滴度为 4× 1 0 9PFU/ml。结论 成功地构建了RatMMP1 3 重组腺病毒载体 ,为下一步行MMP 1 3转基因治疗低顺应性膀胱的研究提供了条件  相似文献   
104.
7例睾丸静脉和2例卵巢静脉变异的解剖学研究   总被引:2,自引:0,他引:2  
目的:了解睾丸静脉和卵巢静脉的变异。方法:观测了73具(146侧)成人尸体(男58,女15)两种静脉的形态结构。结果:发现两种静脉有变异者7例,其中睾丸静脉5例,卵巢静脉2例,另外,作者还对变异与国内文献作了比较。结论:本研究为探讨睾丸静脉和卵巢静脉曲张发生原因及治疗等提供解剖学资料。  相似文献   
105.
OBJECTIVE: To study the clinical value of muscle autograft denatured by microwave for repair of gaps in removal of facial neuromas. METHODS: Two cases of patients with facial nerve Schwann cell neuromas were reported. The operations for removal of facial neuromas were completed, and the gaps of the nerves were repaired with muscle autograft denatured by microwave of 250 W for 120 sec. RESULTS: The patients were followed up for two years, and the recovery of facial function on the affected sides were satisfactory. CONCLUSION: Muscle autograft denatured by microwave technique is convenient, highly efficient for repairing facial nerve gap after removal of facial neuroma.  相似文献   
106.
Copper (Cu)-dependent lysyl oxidase (LO) catalyzes crosslinking of collagen and elastin stabilizing the extracellular matrix (ECM). Chronic inhalation of cadmium (Cd), a toxic metal, induces emphysema. To probe mechanisms of Cd injury to the lung, we developed Cd-resistant (CdR) cells from rat fetal lung fibroblasts (RFL6) by chronic exposure to CdCl(2) from 1 to 40 microM and further examined their expressions of LO, LO substrates, and Cu-scavenging thiols. Levels of cellular thiols, metallothionein, and glutathione in CdR cells were elevated to 13.0- and 3.2-fold of parental controls, respectively, whereas LO mRNA and protein levels were markedly reduced in these cells, with catalytic activity declining to only 16% of the parental control. A conspicuous 52 kDa species rather then the normal 50 kDa proenzyme appeared in the CdR cell extract but not in the conditioned medium, which was codistributed with the endoplasmic reticulum marker [DiOC5(3)] within the cell, implying the Cd-induced 52 kDa species as a product of an abnormal LO-processing defect in secretion. Addition of Cu into CdR cell cultures enhanced the expression of LO mRNA, protein and catalytic activities reflecting limitation of Cu bioavailability for LO in these cells. With inhibition of LO, CdR cells also displayed downregulation of collagen and elastin, substrates of LO. Restoration of collagen synthesis by exposure of CdR cells to purified LO or Cu suggests that inhibition of LO and limitation of Cu cofactor by Cd, as key phenotype changes, accelerated collagen and elastin damage, a critical event pertinent to emphysema pathogenesis.  相似文献   
107.
中国已婚育龄妇女分娩保健服务的状况与变化研究   总被引:5,自引:0,他引:5  
目的:分析我国已婚育龄妇女分娩保健服务状况及其变化。方法:对全国31个省(直辖市、自治区)抽取的调查前三年有生育史的1962名已婚育龄妇女进行问卷调查,结合1997年全国人口与生殖健康调查资料,对两次调查前三年有生育史妇女最近一次活产的分娩保健服务状况进行比较分析。结果:①与1997年调查前三年相比,2001年调查前三年育龄妇女的入院分娩率增加,家庭分娩的比例明显减少;②农村妇女家庭分娩比例明显降低,由1997年调查时的61·41%降为2001年调查时的40·78%,1998~2000年间,92·54%城镇妇女接受分娩保健服务,农村妇女家庭分娩比例高出城镇7·4倍,为40·78%;③分娩保健服务在各地区发展不平衡,东部和中部地区发展快,西部地区,尤其是西南地区发展相对较慢,1998~2000年间,西部地区妇女中,一半以上在家分娩,西部地区农村家庭分娩妇女一半以上由家人接生,约为东部和中部地区的6倍;④少数民族妇女家庭分娩和由家人接生的比例明显高于汉族妇女;⑤随着文化程度和经济收入的增加育龄妇女对分娩保健服务的利用增加,文盲、经济收入低的妇女家庭分娩比例和由家人接生的比例非常高。结论:我国分娩保健服务状况在改善,但发展极不平衡,西部地区农村的分娩保健服务急待提高。应加强对西部地区分娩保健服务的支持力度,研究制定应对策略,加强对西部农村接生人员的专业技术培训。  相似文献   
108.
Objective To test the hypothesis that p53 gene therapy combined with endostatin can enhance tumor response to radiation therapy of RM-1 mouse xenograft prostate cancer and to investigate its mechanism. Methods A mouse prostate cancer model was established. Then mice with xenograft tumor were randomly divided into group A (control), B (radiation), C (radiation and rAdp53), D (radiation and rh-endostatin) and E (radiation and rAdp53 and rh-endostatin). On day 1, rAdp53 was injected intra-tumorously with 1 × 1010 vp per animal to group C and E. From day 1 to 14, rh-endostatin was given 15 mg/kg intraperitoneally daily to group D and E. On day 4 single fraction of 15 Gy was given to tumors in groups B, C, D and E. Normal saline was injected intra-tumorously or intraperitoneaUy accordingly as control. No treatment was done to group A. Tumor volume was measured daily. Samples were collected on Days 5, 10 and 15. Ki67, CD31, p53 and VEGF were detected by means of immunohistochemistry. Results (1) Radiation alone, radiation combined with intra-tumorous injection of Adp53 and/or intraperitoneal injection of rh-endostatin resulted in tumor growth arrest of RM-1 cells in vivo (P = 0.000). Radiation combined with both rAdp53 and rh-endostatin was the most effective treatment (P < 0.05). (2) All the four treatment groups had a decreased expression of mutant type P53 (P = 0.000). The expression of Ki67 in groups B and C were equal (P 0.05) and increasing (P = 0.000), respectively. Group D had a up-down-up curve (P < 0.05), but group E had a up-down one. On day 5 the expresion of VEGF in group E was the lowest (P < 0.05). An increased expression of MVD compared with the control was shown, and MVD in groups C, D and E were always higher than that in the control (P < 0.05). Conclusions The limitation of radiotherapy could be overcome by combination with beth p53 gene therapy and endostatin on the growth of mouse prostate cancer cell. Radiation, rAdp53 and endostatin have their own role but they can be interacted with each other.  相似文献   
109.
患者,女,52岁,因突发呼吸困难5h入院,既往有肺结核病史20a,慢性支气管炎病史10a。X线表现:右肺外带异常透亮,并见压缩肺组织边缘,肺压缩约50%,压缩之肺组织上部见致密斑点影(见图1)。气管纵隔明显左移,左膈明显升高达左胸中部,经透视证实为左膈疝,疝入胸腔组织为胃(见胃泡)。左肺野上部透亮度明显增加,并见清晰光滑边缘,结合透视证实为左肺自发性气胸。双侧胸廓较对称,未见明显塌陷改变。X线诊断:右肺陈旧TB;双侧自发性气胸伴左膈疝形成。讨论:自发性气胸是指在无外伤和人为因素的情况下,肺组织及脏层胸膜突然破裂而引起的胸腔积气。自发…  相似文献   
110.
We previously reported that lymphatic mapping using isosulfan blue can be used to identify sentinel nodes (SNs). This study was undertaken to evaluate the feasibility of using the SN technique in treating early gastric cancer and to explore its usefulness for minimal invasive surgery. Twenty-three patients with early gastric cancer who underwent SN biopsy were retrospectively evaluated. Based on SN evaluation, individualized surgery was performed in five patients with T1N0M0 gastric cancer. When pathological examination of frozen sections revealed metastasis in SNs, we performed a standard D2 gastrectomy. Laparoscopic local resection was applied when the SN biopsy was negative. Our results showed that the success rate with SN biopsy in early gastric cancer was 100%, as were the accuracy, sensitivity, and specificity. All five patients with early gastric cancer had SNs negative for metastases both by frozen section and by postoperative pathology. Thus, all these patients underwent laparoscopic local resection without extended lymphadenectomy. We conclude that SN biopsy is a useful tool to individualize the operative procedure, and laparoscopic local resection can be safely performed using SN guidance in selected patients with early gastric cancer.  相似文献   
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