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31.
目的观察化浊清解愈溃煎对溃疡性结肠炎(UC)大鼠血清及结肠组织p38MAPK、肿瘤坏死因子-α(TNF-α)、白细胞介素-4(IL-4)含量的影响。方法清洁级Wistar雄性大鼠50只按随机数字表法分为两组,空白组8只,其余大鼠均为造模组。采用TNBS/乙醇联合造模法构建UC大鼠模型。造模成功后按照随机数字表法将模型大鼠分为模型组、西药组(予美沙拉嗪肠溶片混悬液0.42 g/kg)及中药高、中、低剂量组。中药高、中、低剂量组予化浊清解愈溃煎中药混悬液,剂量分别为22、11、5.5 g/(kg·d),每日灌胃1次,疗程14 d。采用免疫组化法检测各组大鼠结肠组织内p38MAPK的蛋白表达量。ELISA法检测各组大鼠血清内TNF-α、IL-4含量。结果与空白组比较,模型组一般情况较差,血清中TNF-α含量显著升高(P<0.05),IL-4含量则明显降低(P<0.05),结肠组织中p38MAPK水平明显升高(P<0.05)。与模型组比较,西药组、中药各剂量组大鼠一般生存状况改善明显,血清中TNF-α含量下降,IL-4含量明显升高,尤以中药高剂量组和西药组疗效显著(P<0.05)。结论化浊清解愈溃煎高、中剂量可改善UC大鼠一般生存状况,并通过调节血清中IL-4含量,下调TNF-α表达水平和结肠组织中p38MAPK蛋白表达水平而达到保护结肠黏膜和治疗UC的作用。 相似文献
32.
目的研究吗啡依赖和戒断时大鼠杏仁核中神经甾体和氨基酸递质水平的变化。方法连续7天给予大鼠盐酸吗啡建立吗啡依赖模型。使用纳洛酮(2mg/kg)催促戒断,观察戒断症状并进行评分。将大鼠断头处死后,剥离大脑并分离出杏仁核,用液-液萃取和固相萃取法提取游离型和结合型神经甾体。神经甾体(包括脱氢表雄酮、孕烯醇酮、别孕烯醇酮、脱氢表雄酮硫酸酯和孕烯醇酮硫酸酯)的含量使用高效液相色谱-质谱法测定。甘氨酸、谷氨酸和γ-氨基丁酸的含量采用柱前OPA衍生-电化学检测-高效液相色谱法测定。结果与盐水对照组相比,吗啡依赖大鼠杏仁核中的脱氢表雄酮水平降低33 %(P<0·01)。与戒断对照组比较,吗啡戒断大鼠杏仁核中的孕烯醇酮和别孕烯醇酮水平分别升高45 %和42 %(P<0·05) ,γ-氨基丁酸水平降低18 %(P<0·01)。与吗啡依赖组比较,吗啡戒断组大鼠杏仁核中的孕烯醇酮和孕烯醇酮硫酸酯水平分别升高60 %和40 %(P<0·05) ,甘氨酸水平降低14 %(P<0·05)。结论吗啡依赖大鼠杏仁核中的脱氢表雄酮可能参与吗啡依赖的形成而与吗啡戒断症状的表达无关。其他神经甾体(包括孕烯醇酮、别孕烯醇酮和孕烯醇酮硫酸酯)则可能参与吗啡的戒断而与依赖的形成无关。纳洛酮催促戒断时,大鼠杏仁核中抑制性氨基酸递质的合成和释放受到抑制。表明大鼠杏仁核中的各种神经甾体和氨基酸递质在吗啡依赖和戒断时发生了不同的变化。 相似文献
33.
Daoyan Wei Henry Q. Xiong James L. Abbruzzese Keping Xie 《Journal of gastrointestinal cancer》2003,33(1):43-60
Pancreatic cancer is a lethal disease characterized by early metastasis, local invasion, and resistance to conventional therapies. To understand its etiology and eventually make prevention of it possible and effective, appropriate carcinogenesis models will certainly help us understand the effects of environmental and genetic elements on pancreatic carcinogenesis. The development of new treatment strategies to control cancer metastasis is of immediate urgency. Fulfillment of this task relies on our knowledge of the cellular and molecular biology of pancreatic cancer metastasis and the availability of biologically and clinically relevant model systems. Many of the existing pancreatic cancer carcinogenesis and metastasis animal models are described in this review. The advantages and disadvantages of each model and their clinical implications are discussed, and special attention is focused on experimental therapeutic strategies targeting pancreatic cancer metastasis. 相似文献
34.
Flavia M. N. P. Aslanian Maria Teresa Q. Marques Haroldo J. Matos Luciane F. S. Pontes Luis Cristvo S. Porto Lucia M. S. Azevedo Absalom L. Filgueira 《Journal der Deutschen Dermatologischen Gesellschaft》2006,4(10):842-847
Background: Lichen sclerosus (LS) has been identified with increased frequency in families,often associated with HLA markers, mainly DQ7. A genetic co‐etiology seems likely in this setting. Moreover, there is an association of LS with autoimmune disorders, such as the presence of anti‐thyroid peroxidase autoantibodies (anti‐TPO), a hallmark of autoimmune thyroid diseases. Patients and Methods: In 3 families affected by LS, we verified their HLA markers, and identified previously undiagnosed cases of LS and autoimmune disorders. 30 individuals were examined with history, skin biopsy, HLA class I and II typing by PCR‐SSP, and measurement of anti‐TPO, free thyroxine and thyroidstimulating hormones (TSH) levels. Results: There were 8 cases of LS, 50 % of them anti‐TPO+. Autoimmune disorders were found in 40 % (total) and in 87.5 % of those affected. Most common HLA markers were B*15, B*57, CW*03, CW*07, CW*18, DRB1*04, DRB1*07, DRB4*. The three latter have been previously associated with LS. Conclusion: New cases of LS and autoimmune disorders can be detected in first degree relatives of patients with LS. The presence of anti‐TPO antibodies strongly suggests autoimmune thyroiditis. There is intra‐familial association between the haplotype HLA‐B*15 ‐DRB1*04 ‐DRB4* and anti‐TPO,emphasizing their link with thyroiditis. New familial approaches might help to make clear the pathogenesis of LS and its association with autoimmune diseases. 相似文献
35.
36.
目的 研究乙型肝炎病毒(HBV)自身增强子I(enhancerI,ENHI)对HBV DNA疫苗免疫应答的影响。方法 采用PCR法以HBVadr亚型全基因DNA序列为模板分别扩增表面抗原(HBsAg)和HBsA-ENHI基因片段,重组到载体VR1012中,构建两种HBV DNA疫苗,转染CADS-7细胞及HepG2细胞并免疫BALB/c小鼠。采用蛋白印迹、ELISA、ELISPOT等方法检测其在COS-7和HepG2细胞内的表达及小鼠的体液及细胞免疫应答效果。结果 转染的HepG2和COS-7细胞均表达HBsAg;连接ENHI的HBV DNA疫苗转染HepG2细胞后HBsAg表达量明显升高,两种疫苗转染COS-7细胞表达HBsAg无明显差异;免疫小鼠后第2周产生HBsAb及HBsAg特异性细胞毒T淋巴细胞(CTL),两种疫苗免疫产生的HBsAb及HBsAg特异性CTL无明显差异。结论ENHI可使HBV DNA疫苗转染HepG2细胞表达HBsAg明显增加,对转染COS-7细胞表达HBsAg及接种BALB/C小鼠引起的免疫应答无明显影响。 相似文献
37.
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39.
Emir Q. Haxhija Prof. Dr. Johannes M. Mayr Wolfgang Grechenig Michael E. Höllwarth 《Operative Orthopadie und Traumatologie》2006,18(2):120-134
OBJECTIVE: Surgical reduction and retention of apophyseal avulsion injuries at the medial epicondyle to prevent joint instability, lasting malalignment, or pseudarthrosis. INDICATIONS: Absolute: intraarticular apophyseal dislocation of the medial epicondyle, complete lesion of the ulnar nerve. Relative: dislocation of the apophysis (> 4 mm) in children > 5 years of age; the need for intervention increases in children as the degree of dislocation, age, and athletic activity increase. CONTRAINDICATIONS: Dislocation of the medial epicondyle (< or = 4 mm) in children < 5 years of age, provided the fragment location is not intraarticular. SURGICAL TECHNIQUE: Open reduction of the apophysis through a medial approach. Identification of the ulnar nerve. In young children or with small fragments fixation with Kirschner wire. Screw fixation in older children or for larger fragments. POSTOPERATIVE MANAGEMENT: Long upper-arm plaster cast until wound healing is achieved. Subsequently, upper-arm plaster cast for 3 weeks. Removal of Kirschner wires after 4-6 weeks, screw removal after 8-12 weeks. Physiotherapy only if marked reduction of elbow mobility is found 6 weeks after cast removal. RESULTS: From January 1, 1994 to December 31, 2003, 25 children with an average age of 12 years suffering from medial epicondylar avulsion fractures were operated on using open reduction and Kirschner wire fixation. An average of 3 years after the injury 14 of these children underwent follow-up examination using a procedure that took subjective, clinical and radiologic parameters into account. Two children showed a slight reduction in overall strength of the injured extremity when compared with the contralateral extremity. One child had a flexion deficit of 10 degrees, all other children showed movement limitations of < or = 5 degrees compared to the contralateral extremity. In all the cases available to follow-up, there was a slight increase in valgus alignment of the elbow joint compared with the uninjured side (3 degrees on average). All fractures consolidated within 6 weeks. 相似文献
40.
实习护士的压力源分析及带教老师的应对方式 总被引:4,自引:0,他引:4
护理工作是脑力和体力相结合的双重劳动,对于接触这一工作不久的实习护十来说。由于特定的工作性质和职业的高要求,其身心承受很大的压力。为此,调查了我院115名实习护士压力的影响因素,所获得的信息将有助于临床工作者针对性地采取减轻压力措施,帮助护生掌握应对压力的有效策略,使实习护士在适度的压力状态下身心健康的学习工作,成为护理事业合格的后备力量。 相似文献