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991.
家兔实验性动脉粥样硬化血管重塑的形态定量分析   总被引:1,自引:0,他引:1  
目的 :探讨AS血管重塑的几何形态变化规律。方法 :将 40只新西兰雄性家兔随机等分为正常对照组 (C组 )和动脉粥样硬化模型组 (AS组 ) ,分别于实验的第 4、8、12周末取各组家兔的胸主动脉进行定性观察及定量分析。结果 :随时间延长 ,AS组斑块面积逐渐增大 ,斑块检出率逐渐增加。管腔面积在早期斑块形成时并无改变 ,晚期则明显缩小。斑块面积及管腔面积均分别与内弹性膜包围面积 (IELA)、外弹性膜包围面积 (EELA)呈正相关关系 (P <0 .0 5 ) ,IELA和EELA间也呈显著正相关关系 (P <0 .0 1) ,但斑块面积与管腔面积间并无直线相关关系 (P >0 .0 5 )。结论 :家兔AS病变随时间延长逐渐加重 ,且在斑块形成时伴内弹性膜和外弹性膜的同时扩张 ,管腔狭窄与否主要与IELA和EELA相关。IELA和EELA可作为判断管腔狭窄及评价血管重塑的指标。  相似文献   
992.
边远驻军官兵身心健康状况及相关因素的调查   总被引:2,自引:0,他引:2  
目的:调查边远驻军官兵的身心健康状况及其影响因素。方法:以边远驻军官兵为被采用症状自评量素(SCL-90),孤独量表(非大学生版)及自编的一般情况问卷进行测评。结果:250人中有72人(29.2%)存在不同程度的身心健康问题,其中人际敏感,躯体化和强迫症状等是边远驻军官兵主要问题,与部队常模及军校大学生比较,边远驻军官兵的身心健康水平相对较差;其身心健康问题与孤独感,对环境的不适应,睡眠问题及自慰行为存在着显著的线性关系。结论:总体上边远驻军兵的身心健康水平相对较差,存在身心症状的人数较多,其中孤独感,对环境的不适应,睡眠问题及自慰行为等是主要的影响因素。  相似文献   
993.
We purified the 17 kDa protein abundant in Clonorchis sinensis crude extracts. The N-terminal amino acid sequence of this protein was determined and an oligonucleotide probe synthesized. Using this probe, the cDNA encoding the protein was cloned and sequenced from the C. sinensis cDNA library. It was found to consist of a total of 150 amino acids and to have 41% conserved homology with the myoglobin of the trematodes Paramphistomum epiclitum and Isoparorchis hypselobagri. The gene product over-expressed in the bacterial system was purified and identified as the same molecule in the adult worms. BALB/c mouse sera raised against the adult 17 kDa protein revealed that this myoglobin was distributed throughout the parenchymal tissues except for the eggs and reproductive organs and that the protein may be involved in the survival of C. sinensis in the oxygen-depleted environment of the host.  相似文献   
994.
Hypertension is an age-dependent disorder. Oxidative stress has been suggested to play a role in aging and age-dependent disorders. The objective of this study is to examine the oxidant and antioxidant status in the aorta of a mouse model with high blood pressure (BPH). Our results showed that the level of malondialdehyde (MDA) in the aorta of BPH mice was approximately 2.6-fold higher than that of the normal blood pressure (BPN) mice, suggesting an increased in vivo oxidative stress in the arterial wall of BPH mice. In addition, the release of hydrogen peroxide (H2O2) from the aorta of BPH mice was significantly faster than that of BPN mice. To determine if the increased H2O2 release is related to a down-regulation of antioxidant enzymes in the arterial wall, we measured the activities of the major antioxidant enzymes in mouse aortas. We observed that the activities of Cu/Zn-superoxide dismutase (SOD) and glutathione peroxidase-1 in BPH mice were similar to BPN mice. On the other hand, the catalase activity in the aorta of BPH mice was significantly reduced while the activities of Mn-SOD and extracellular (EC)-SOD in the aorta of BPH mice were significantly elevated as compared with BPN mice. These results suggest that increase in SOD activity and decrease in catalase activity might be responsible for the increased release of H2O2 in the arterial wall of BPH mice.  相似文献   
995.
DMD患者骨骼肌抗肌萎缩蛋白表达与临床病理改变   总被引:2,自引:0,他引:2  
目的探讨抗肌萎缩蛋白(dystrophin)免疫组织化学检查的临床价值及与Duchenne型肌营养不良(DMD)临床病理改变之问的相关性。方法通过组织学观察和免疫组织化学方法,对36例DMD患者骨骼肌dystrophin的表达情况、临床表现和肌肉病理改变进行观察分析。结果发现25例年龄在4岁以上的患儿多有比较典型的DMD临床表现,而11例4岁以下患儿症状比较轻。肌肉病理显示15例早期改变,17例中期改变,4例晚期改变,病理改变的严重程度与年龄相关。免疫组化染色显示36例患者的肌肉标本均有严重的dystrophin缺失,其中9例完全缺失,10例部分肌纤维膜有微弱着色,17例极少数肌纤维膜清楚着色,dystrophin的表达分级与病理改变分期及年龄无明显相关。结论检查dystrophin在肌纤维膜上的表达对DMD具有特异性诊断价值,但临床病理改变的严重程度主要与年龄和病程有关。  相似文献   
996.
Park SY  Kim HS  Hong EK  Kim WH 《Human pathology》2002,33(11):1078-1085
The expressions of cytokeratin (CK) 7 and 20 have been studied in various primary and metastatic carcinomas, and their determination may help distinguish the site of origin of metastatic carcinomas. However, little is known about the factors that determine variations in their expression patterns in primary gastric and colorectal carcinomas. We investigated the expressions of CK7 and CK20 in 289 cases of gastric carcinoma and 225 cases of colorectal carcinoma using a tissue microarray. To evaluate CK7 and CK20 expression patterns of ovarian metastases from gastric or colorectal carcinomas, 54 cases of metastatic carcinomas to the ovary were examined. It was found that 71% (207 of 289) of the gastric carcinomas stained positively for CK7, whereas only 9% (21 of 225) of the colorectal carcinomas proved to be CK7 positive, and that 41% (117 of 289) of the gastric carcinomas and 73% (165 of 225) of the colorectal carcinomas were CK20 positive. The proportion of CK7+/CK20- was highest in the gastric carcinomas at 46% (132 of 289), and was independent of the histologic classification of Lauren (46% of the intestinal type, 45% of the diffuse type). The CK7 and CK20 expression patterns were different in colorectal carcinomas according to histologic grade and location of the tumor. CK7-/CK20+ had the greatest proportion (68%) in colorectal carcinomas, and this was dependent on the tumor's histologic grade (75% of low-grade versus 52% of high-grade) and location (46% of right-sided versus 76% of left-sided). Moreover, 42% (18 of 43) of gastric carcinomas metastatic to the ovary were CK7+/CK20-, whereas 19% (8 of 43) were CK7-/CK20+. All colorectal cancers metastatic to the ovary were CK7-/CK20+, except 1 case that was CK7-/CK20-. In conclusion, the CK7 and CK20 expression patterns in primary gastric carcinomas vary considerably, and those in colorectal carcinomas are associated with histologic grade and tumor location. The CK7-/CK20+ expression pattern is specific for metastatic colorectal carcinomas to the ovary, but has low predictability for colorectal origin in metastatic ovarian carcinoma.  相似文献   
997.
目的 探讨支气管动脉超选择性介入化疗及栓塞治疗肺癌的疗效。方法 58例肺癌病人均行支气管动脉超选择性介入化疗栓塞术,观察治疗前后原发癌灶体积及最大直径与垂直直径的变化,比较肺CT影像学改变;观察栓塞剂用量与癌灶体积之间的关系;观察临床病征、介入并发症等情况,并进行分析。结果 支气管动脉超选择性介入化疗栓塞术治疗肺癌疗效显,术后原发癌灶的体积大多有不同程度缩小,肿瘤最大直径与垂直直径乘积缩小,降低50%以上的占89.66%,栓塞剂用量小,介入并发症出现率低,副反应轻。  相似文献   
998.
We report a case of ruptured mycotic aneurysm involving innominate artery requiring an urgent surgical treatment. A 62-yr-old woman presented with fever and dyspnea. Previously, she was diagnosed with colon cancer and received right hemicolectomy and one cycle of adjuvant chemotherapy. On echocardiogram, pericardial effusion was noted and emergency pericardiocentesis was performed. CT scan revealed aortic aneurysm involving ascending aorta and innominate artery, and thrombi surrounding those structures. Patch repair of the defect in the ascending aorta and ringed Goretex graft to bypass the innominate and ascending aorta were performed. We believe that this is the first case of ruptured mycotic aneurysm involving innominate artery.  相似文献   
999.
目的:以THP-1巨噬细胞源性泡沫细胞为研究对象,观察载脂蛋白A-I对THP-1巨噬细胞源性泡沫细胞胆固醇流出和三磷酸腺苷结合盒转运体A1(ABCA1)的影响,从而探讨载脂蛋白A-I对动脉粥样硬化(As)发生发展的影响。方法:用液体闪烁计数器检测细胞内胆固醇流出, 高效液相色谱分析细胞内总胆固醇、游离胆固醇和胆固醇酯含量, 运用逆转录-多聚酶链反应和Western 印迹分别检测ABCA1 mRNA 与ABCA1蛋白的表达,用流式细胞术检测细胞平均ABCA1荧光强度。 结果:载脂蛋白A-I引起THP-1巨噬细胞源性泡沫细胞总胆固醇、游离胆固醇与胆固醇酯呈时间依赖性减少, 而ABCA1蛋白质水平、细胞平均ABCA1荧光强度以及细胞内胆固醇流出呈时间依赖性增加,但ABCA1 mRNA没有明显变化。巯基蛋白酶抑制剂(leupeptin 和ALLN)增加ABCA1蛋白质水平,而其它蛋白酶抑制剂(pepstatin A、aprotinin及phosphoramiddon)不增加ABCA1蛋白质水平,蛋白体抑制剂(lactacytin)和溶酶体抑制剂(NH4Cl)也不影响ABCA1蛋白质水平。 结论:巯基蛋白酶可降解THP-1巨噬细胞源性泡沫细胞ABCA1蛋白质,而载脂蛋白A-I可阻碍巯基蛋白酶降解ABCA1蛋白质,从而提高THP-1巨噬细胞源性泡沫细胞ABCA1 蛋白质水平, 增加细胞内胆固醇流出, 降低细胞内胆固醇聚积。  相似文献   
1000.
目的:探讨胃泌素对大鼠胃粘膜环氧合酶(COX)及生长因子表达的影响。方法:雄性SD大鼠皮下注射胃泌素1 μg/kg、10 μg/kg或100 μg/kg,Western blot和免疫组化检查胃粘膜COX-1、COX-2、肝细胞生长因子(HGF)和肝素结合表皮生长因子样生长因子(HB-EGF)表达。评价胃泌素受体拮抗剂YM022对COX-1、COX-2、HGF和HB-EGF表达的影响。结果:胃泌素剂量依赖性地增加大鼠胃粘膜COX-2和HB-EGF表达,而对COX-1和HGF表达无明显影响;YM022阻断胃泌素诱导的COX-2和HB-EGF表达。 结论: 胃泌素调节大鼠胃粘膜COX-2和HB-EGF蛋白表达,提示COX-2和HB-EGF参与与胃泌素相关联的胃粘膜增生和胃癌等的发病过程。  相似文献   
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