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991.
探析我国医药市场结构的演变   总被引:1,自引:0,他引:1  
张周卫 《中国药业》2005,14(9):18-19
实证分析我国医药市场结构变化发展两个阶段的特征,探究其演变的历史趋势.  相似文献   
992.
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   
993.
张霞 《卫生职业教育》2010,28(22):26-27
高等院校校园危机频繁发生,危机管理已成为校园稳定和发展的重要内容。校园危机管理包括校园危机预防和校园危机处理。而危机管理重在预防,强化危机意识是危机预防的立足点和出发点。危机处理是危机管理的关键环节,即危机出现时运用有效的危机佘关手段正确处理危机,消除影响。  相似文献   
994.
The recent development of 2-dimensional strain (2D strain) imaging can provide a powerful alternative for assessing left ventricular (LV) torsion. This study was conducted to evaluate the global and regional left ventricular twist by 2D strain in patients with anterior wall myocardial infarction (AMI). A total of 55 AMI patients were divided into two groups according to their ejection fraction (EF) values (group A: LVEF ⩾ 50%; group B: LVEF < 50%), and 35 normal people served as the control group. Using 2-dimensional strain software, global and regional LV rotation and displacement were obtained at two planes. Compared with the control group, patients of group A showed reduced peak LV twist of the anterior and anterior-septal wall (9.26±1.89 vs 10.74±2.67; 9.71±1.71 vs 11.36±2.29, both P < 0.05), but the radial displacement and global twist were maintained (P > 0.05). Differently, regional and global LV twist and radial displacement in patients of group B deceased significantly, especially in the anterior and anterior-septal wall, as compared with patients in the control or group A (both P < 0.05). Moreover, a strong correlation was noted between peak twist and radial displacement; the twist-displacement loop was markedly distorted in patients of group B. This study demonstrated that 2D strain has a potential ability for quantification of left ventricular global and segment twist and radial displacement in patients with coronary artery disease.  相似文献   
995.
Background: Chronic pain models are commonly defined as either nerve-injury or inflammation models, but recent work suggests inflammatory processes are important in nerve injury-induced pain.

Methods: In the rat spinal nerve ligation model, the authors examined effects of systemic corticosteroid triamcinolone acetonide (TA) on the cytokine protein profile and sympathetic sprouting in the axotomized sensory ganglia, excitability of sensory neurons, and mechanical sensitivity.

Results: By postoperative day 3, marked increases (5- to 16-fold) in monocyte chemoattractant protein-1, growth-related oncogene (GRO/KC or CXCL1), and interleukin (IL)-6 were observed, whereas IL-4 and IL-2 levels fell more than fourfold. The increased cytokines and number of sympathetic basket formations in the sensory ganglia were reduced toward normal values by TA given starting at the time of injury. Interleukin-4 and IL-2 levels were not restored by TA. Systemic TA also reduced the firing rate and incidence of bursting activity, but not the overall incidence of spontaneous activity, in large- and medium-sized neurons. Mechanical hypersensitivity on postoperative day 3 was reduced by TA, and some effect could still be observed 4 days after cessation of TA. However, starting TA at day 7 was ineffective.  相似文献   

996.
护理科学研究的对象是人,并且是一批特殊的人群,他们不但承受着躯体的痛苦,而且存在多种心理健康问题。护理科研设计是护理科学研究中非常重要的环节,是对科学研究具体内容和方法的设想和安排,所以护理科研设计应突出人性化,以人为本,以减轻病人痛苦、促进早日康复为目的。  相似文献   
997.
化痰方、肝脾方抗大鼠脂肪肝模型作用机制的比较研究   总被引:7,自引:1,他引:6  
目的 :探讨和比较化痰方、肝脾方抗大鼠脂肪肝模型作用机制。方法 :用高脂饮食联合四环素腹腔注射致大鼠脂肪肝模型 ,观察肝组织病理变化 ,检测肝功能 (ALT、AST)、血甘油三酯 (TG)、肝匀浆TG、游离脂肪酸 (FFA)、丙二醛 (MDA)的含量。并与正常组、东宝肝泰组对照。结果 :三个用药组的血清ALT、AST及肝匀浆FFA、TG、MDA均显著低于模型组 (P <0 .0 1 ) ,并显示抗脂肪肝的作用强弱依次为 :肝脾组优于化痰组优于东宝组 (P <0 .0 5或P <0 .0 1 )。结论 :促进脂质代谢、抗脂质过氧化可能是化痰祛浊、疏肝健脾法治疗脂肪肝作用的主要机制  相似文献   
998.
33例肝占位性病变MRI误诊的分析   总被引:1,自引:0,他引:1  
我院1988年以来4000余例腹部MRI中,发现肝占位性病变误诊33例。所用机型为美国Disonics公司0.5T超导MRI,自旋回波序列(SE序列)、常规T1加权(T1WI)、质子加权(PDWI)、T2加权(T2WI),覆盖全肝。其中,PHC误诊为MHC5例、MHC误诊为PHC6例、PHC误为HHE5例、MHC误诊为HHE2例、HHE误诊为PHC6例、肝硬化结节误诊为PHC2例、炎性假瘤误诊为PHC3例、肝结核误诊为PHC1例、HCY误诊为HHE3例。本文从病变的影像学特征和扫描技术方面详细探讨了误诊的原因和鉴别诊断要点。  相似文献   
999.
颅内生殖细胞瘤综合治疗   总被引:4,自引:0,他引:4  
报告50例颅内生殖细胞瘤,手术治疗19例,放射治疗43例。综合治疗后临床症状改善41例,无效2例。随访32例,其中恢复正常工作或学习者14例,生活能自理12例,生活部分需人帮助4例,死亡2例。5年生存率为50%。推荐放疗为首选治疗手段,并对合并颅内压增高及多发性、复发性肿瘤的治疗作了讨论。  相似文献   
1000.
低温体外循环下手术治疗主动窦瘤破裂16例,采用右房切口1例,右室流出道切口11例,窦瘤破入腔和主动脉根部双切口4例。单纯窦瘤破口修补2例;双头垫片针窦瘤基部与空间隔踬同并列间断褥式缝合修补3例;  相似文献   
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