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51.
BACKGROUND: During formation of prolactin neoplasia, how cells and its structure in adenohypophysis affect prolactin cells should be further studied. Intermediate lobe can be regarded as a driving region to release prolactin (PRL) and may promote formation of prolactin neoplasia in pituitary anterior lobe. OBJECTIVE: To observe the effect of diethylstilbestrol (DES) on the expressions of μ and m-calpains in pituitary intermediate lobe of female Wistar rats. DESIGN: Observational contrast animal study. SETTING: Beijing Neurosurgical Institute. MATERIALS: A total of 21 female Wistar rats, 3 weeks old weighing 70–80 g were housed with free access to tap water and standard pellet food. They were kept in a CL-grade condition, at (24±1)℃ and a humidity of (55±5)%, and with a 12 hours day-night cycle. Caprine anti-μ- and m-calpains antibodies were provided by Santa Cruz Biotechnology, CA, USA; rabbit-anti-PRL antibodies by Dako, Denmark; rabbit-anti-ACTH antibody by Boster Company, Wuhan. METHODS: The experiment was carried out in Pathophysiological Department and Animal Laboratory, Beijing Neurosurgical Institute from August 2006 to January 2007. ① Rats were randomly divided into groups with 7 in each group, including vehicle control group, in which rats were injected intraperitoneally with sun-flower seed oil (1 mL/kg, twice a week) for 16 weeks; DES group, where animals were administered with DES (5 mg/kg, twice a week) for 16 weeks; DES + vehicle control group, in which DES was administered for 12 weeks at the same dose with those in DES group, and then was discontinued and replaced by sun-flower seed oil (1 mL/kg, twice a week) for the following 4 weeks. ② At 16 weeks later, pituitary tissue was dealt with HE staining and PRL immunohistochemical examination to observe evoke of tumor; meanwhile, immunohistochemical examination was used to observe expression of PRL of pituitary anterior lobe, expressions of μ- and m-calpains of pituitary intermediate lobe and distribution of adrenocorticotropin. MAIN OUTCOME MEASURES: ① Expression of PRL of pituitary anterior lobe, expressions of μ- and m-calpains of pituitary intermediate lobe and distribution of adrenocorticotropin. ② Morphological observation of pituitary tissue. RESULTS: All 21 rats were involved in the final analysis. ① Results of immunohistochemical examination: Morphological changes of neoplasia in DES group were strongly positive to PRL, and this suggested that formation of prolactin adenoma was observed in pituitary tissue. As compared with vehicle control group, expression of adrenoeorticotropic hormone (ACTH) was increased in both DES group and DES + vehicle control group. In addition, expressions of μ- and m-calpains in pituitary intermediate lobe were higher in DES group than that in vehicle control group. Otherwise, expressions of m-calpains in pituitary intermediate lobe was decreased in DES + vehicle control group, but expression of μ-calpains was still increased. ② Morphological observation of pituitary tissue: Gland tubes were orderly arranged in rats in vehicle control group. Anterior pituitary gland in rats of DES group demonstrated an apparent disappearance of gland tubes and a relatively large-scaled vasculature formation, namely the vascular lake lined by tightly arranged endothelial cells. Local integrated tumor cell arrangements were also detected. In addition, the border between the IL and the anterior lobe was locally blurred. The definite tumor-like changes in pituitary tissues were confirmed in 6 of 7 female Wistar rats in DES group, and one spontaneous occurrence of tumor formation was found in vehicle control group. In DES + vehicle control group, DES withdrawal led to the subtile emergence of gland tube cavity, although tumor-like cells still existed in 4 of 7 rats, suggesting occurrence of the tumor regression due to the withdrawal of DES. CONCLUSION: A long-term application of DES can enhance the expressions of ubiquitours neutral cysteine protease in pituitary intermediate lobe and this suggests that both of them play a key role in release of hormone and formation of prolactin neoplasia through directly promoting PRL expression and release of neighboring pituitary intermediate lobe.  相似文献   
52.
Methyl tert-butyl ether which is a powerful cholesterol monohydrate solvent does not completely dissolve mixed cholesterol gallstones when directly infused into the biliary tree. In this work, we compared the effect of various solvents containing different proportions of methyl tert-butyl ether and dimethylsulfoxide in anhydrous and aqueous systems on the in vitro solubilization of human cholesterol stones. The dissolution rates of cholesterol obtained in the presence of methyl tert-butyl ether was markedly decreased when 10 p. 100 water was added. In contrast, the addition of dimethylsulfoxide (30 p. 100) to methyl tert-butyl ether-water system enhanced the stone-solvent contact, improved the cholesterol dissolution rates and left less stone debris. A subsequent dissolution with an alkaline, pH = 8.8, aqueous dimethylsulfoxide-ethylenediaminetetraacetic acid solution strongly reduced the non cholesterol residues. In vivo, nearly complete dissolution of human cholesterol stones implanted in the gallbladder of rabbits was obtained within 8 hours when methyl tert-butyl ether/dimethylsulfoxide (70/30) solvent was infused at a rate of 0.6 ml/h/kg. With methyl tert-butyl ether, only 84 p. 100 of the original stone weight was dissolved. The infusion of these solvents leads to morphological changes in the gallbladder wall with some focal ulcerations. These alterations can be almost completely recovered after two weeks. No histologic evidence of hepatic, duodenal or renal damage was found. We conclude that the mixture methyl tert-butyl ether/dimethylsulfoxide (70/30) constitutes a good solvent for mixed cholesterol stones. Compared with pure methyl tert-butyl ether, the mixed system allows for a more rapid and a more complete dissolution of gallstones.  相似文献   
53.
应用0.5%环孢霉素A(cyclosporin A,CsA)滴眼治疗穿透性角膜移植术后发生免疫排斥患者16例(16只眼),治愈9只眼,好转6只眼,无效1只眼。随访5~24个月,其中2只眼因停药复发,1只眼于拆线后复发,继续用药或增加给药次数后治愈。研究表明0.5%CsA滴眼剂治疗术前移植床条件较好,角膜移植术后发生免疫排斥的病例可得到良好疗效;而对术前移植床条件较差,角膜移植术后发生免疫排斥的病例有一定的疗效。作者对眼局部应用CsA治疗角膜移植排斥的疗效和作用机理进行了讨论。  相似文献   
54.
应用DNA重组技术将编码人碱性成纤维细胞生长因子(bbFGF)的基因克隆至原核高效表达质粒pBV_(221)的启动子下游。SDS-SAGE、ELISA和NTT活性监测结果表明:该重组质粒pBV-hbFGF在大肠杆菌DH5α中,经42℃诱导后,可表达出有较高生物活性的hbFGF。  相似文献   
55.
抗人膀胱癌免疫毒素的构建及其体外靶细胞杀伤活性   总被引:3,自引:0,他引:3  
  相似文献   
56.
煤烟型大气污染对儿童肺功能的影响   总被引:4,自引:1,他引:3  
为观察煤烟型大气污染对儿童健康的影响 ,选择了太原市 3个污染程度不同地区的 45 0名儿童进行肺功能测试和问卷调查。研究结果显示 ,儿童呼吸功能表现为重度污染区 <中度污染区 <相对清洁区 ;肺通气功能阻塞性异常率表现为重度污染区 >中度污染区 >相对清洁区 ;Logistic回归分析发现肺通气功能阻塞性异常率与小学生家庭的取暖方式、厨房和卧室是否分开以及污染物的水平有关 ;多元线性回归分析显示重度污染区儿童的FVC、FEF5 0与相对清洁区相比分别减少了 65 80ml、119 2 7ml,中度污染区儿童的FVC、FEF5 0与相对清洁区相比分别减少了 5 7 2 8ml和 114 2 9ml;Ln(SO2 )每升高一个单位 ,FVC和FEF5 0分别减少69 10ml和 119 79ml,Ln(PM1 0 )每升高一个单位 ,FVC、FEF5 0等分别减少了 193 5 0ml和 171 69ml。结果提示 ,太原市煤烟型大气污染对儿童呼吸系统产生了危害。  相似文献   
57.
用适宜浓度的PEG将囊虫病人血清浓缩,达到提高血清中特异性抗体浓度的作用,从而提高检测的敏感性。该法用于囊虫病的诊断,阳性附合率83.33%.特异性较理想。  相似文献   
58.
Lung cancer and prior tuberculosis infection in Shanghai   总被引:1,自引:0,他引:1  
In a population-based case-control study of lung cancer in Shanghai involving interviews during 1984-86 with 1,405 cancer patients and 1,495 controls, a significant 50% elevation in the risk of lung cancer, adjusted for cigarette smoking, was observed among persons who had a history of tuberculosis. Among those diagnosed with tuberculosis within the past 20 years, the risk exceeded 2.5-fold. In males the lung cancers tended to occur on the same side as the previous tuberculosis infection. For both sexes, the effect of recent tuberculosis was most apparent for adenocarcinoma and peripheral tumours. No relationship was found between lung cancer risk and the type of tuberculosis therapy, including use of isoniazid. The findings suggest that tuberculosis may predispose to lung cancer, with the association most apparent among recent survivors of the infection.  相似文献   
59.
Transtemporal supralabyrinthine approach is a modified middle cranial fossa approach. It offers all the advantages of a middle cranial fossa procedure and avoids its disadvantages, mainly the extensive temporal lobe retraction and frightening complications. The principle of the approach is to gain sufficient access toward the internal auditory canal by removing bone from the roof of the petrous pyramid rather than by elevating the middle fossa dura away from it. Fifteen patients underwent this approach for decompression of paralysed facial nerve resulted from temporal bone fracture, Bell's palsy and herpes zoster oticus; for removal of facial neuromas and primary cholesteatomas in temporal bone and for sectioning of great superficial petrous nerve. Preliminary study showed good results.  相似文献   
60.
经胸小切口在食管癌切除手术中的应用   总被引:3,自引:0,他引:3  
目的探讨经胸小切口治疗食管癌手术的地位和可行性。方法对132例不同分期的食管癌行经胸小切口根治性手术,全部采用颈部吻合。结果切口平均长度13.0±2.0 cm,开关胸时间、开胸时出血量、术后伤口疼痛、呼吸功能受限及患肢活动等方面有显著差异,在手术时间、淋巴结清扫、术中出血及术后胸腔引流和常规手术无差异。结论经胸小切口食管癌根治手术安全、可行,并且有创伤小、恢复快等优点,便于推广应用。  相似文献   
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