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101.
目的评价磁共振尿路成像(Magneticresonanceurography,MRU)对泌尿系疾病的诊断价值。方法对36例泌尿系疾病患者进行MRU检查,并结合临床手术、病理资料和其他影像学资料进行回顾性分析。结果36例患者中,均有MRU阳性结果,3例肾盂、肾盏癌,4例前列腺癌,8例前列腺增生症,2例输尿管癌定性、定位明确;9例肾盂、输尿管移行段梗阻定位明确,定性有帮助;10例输尿管下段梗阻中6例诊断明确,4例未能确诊。结论MRU在泌尿系疾病的诊断中,对肿瘤的定位、定性参考价值较高,对尿路梗阻定位诊断有价值,对定性诊断帮助有其局限性。  相似文献   
102.
BACKGROUND: It has been demonstrated that mild hypothermia has obvious protective effect on both whole and local cerebral ischemia. However, the definite mechanism is still unclear for the brain protection of mild hypothermia on cerebral edema, inhibiting inflammatory reaction, stabilizing blood brain barrier, etc. OBJECTIVE: To investigate the effect of mild hypothermia on the expression of vascular endothelial growth factor and the infarct volume after cerebral ischemia in rats, and analyze the brain protective mechanism of mild hypothermia. DESIGN: A randomized grouping and controlled animal trial. SETTING: Department of Neurology, People's Hospital of Yunyang Medical College. MATERIALS: Twenty adult male SD rats of clean degree, weighing (250±30) g, were provided by the animal experimental center, School of Medicine, Wuhan University. The kits for SP immunohistochemistry were purchased from Beijing Zhongshan Golden Bridge Biotechnology Co., Ltd. METHODS: The experiments were carried out in the laboratory of Department of Neurology, Renmen Hospital of Wuhan University from May to July 2005. ① The 20 rats were divided randomly into normal temperature group (n =10) and mild hypothermia group (n =10). Models of permanent middle cerebral artery occlusion were established with modified nylon suture embolization. The rats were assessed with the Longa standards: 0 point for without nerve dysfunction; 1 for mild neurological deficit (fore claws could no extend completely); 2 for moderate neurological deficit (circling towards the affected side); 3 for severe neurological deficit (tilting towards the affected side); 4 for coma and unconscious; 1-3 points represented that models were successfully established. The rats of the normal temperature group were fed at room temperature, and those in the mild hypothermia group were induced by hypothermia from 2 hours postoperatively, and the rectal temperature was kept at 34-35 ℃ for 72 hours. ② Measurement of infarct volume: All the rats were anesthetized by intraperitoneal injection overdose sodium pentobarbital 7 days postoperatively, and then the heads were cut down to harvest brain. The brain tissues were placed into -20 ℃ refrigerator for 20 minutes, coronal sections of 2 mm were prepared. The infarct sites were not stained, whereas normal brain tissues were stained as red. The infarct volumes were calculated by using MPLAS-500 multimedia color pathological image&&word analytical system. ③ Counting positive cells of vascular endothelial growth factor protein: The brains were harvested by cutting heads, then coronal sections of 2 mm were prepared. Routine dehydration, hyalinization, wax immersion and embedding were performed, then the detected with SP immunohistochemistry, the kits were purchased from Beijing Zhongshan Golden Bridge Biotechnology Co., Ltd. The cells whose cytoplasm was yellow-brown were positive ones, a single sample as a unit, peri-ischemic site and ischemic core were selected, and the corresponding sites in controlateral hemisphere were taken as controls. Five visual fields were selected from each site to be observed under microscope, the cells were counted, and the average number of positive cells was calculated in each group. The numbers of positive cells were determined with the image analytical apparatus. MAIN OUTCOME MEASURES: Number of the positive cells of vascular endothelial growth factor protein; Infarct volume of rat brain tissue. RESULTS: All the 20 rats were involved in the analysis of results. ① Number of positive cells of vascular endothelial growth factor protein in brain tissue: It was obviously lower in the mild hypothermia group than in the normal temperature group [(24.02±5.05), (36.07±2.69) cells/high power visual field, P < 0.01]. ② Comparison of infarct volume of brain tissue: After MCAO, it was obviously smaller in the mild hypothermia group than in the normal temperature group [(153.25±23.14), (253.45±36.21) mm3, P < 0.01]. CONCLUSION: Mild hypothermia can inhibit the expression of vascular endothelial growth factor and decrease the volume of cerebral infarction. The inhibition of mild hypothermia on the expression of vascular endothelial growth factor may be one of the brain protective mechanisms.  相似文献   
103.
胰腺实性-假乳头状瘤影像与病理诊断分析   总被引:29,自引:0,他引:29  
目的 探讨胰腺实性-假乳头状瘤的影像及病理学的诊断要点。资料与方法 回顾分析11例经手术切除、病理学和免疫组织化学证实的胰腺实性一假乳头状瘤患者的临床资料,以比较其影像和病理学特点。结果 (1)本病多发于30岁以下女性,临床主要表现为腹痛。(2)CT、MRI表现为肿瘤内有实性和囊性结构,可分为3型;特征性表现为“浮云征”。(3)肿瘤大部分位于胰腺,多有完整包膜,不伴有胆总管扩张。(4)病理学特点为肿瘤实性部分由实性区、假乳头区及两者过渡区以不同比例混合而成。囊性区由坏死、液化、陈旧性出血组成。(5)肿瘤的囊实性结构是形成“浮云征”的病理基础。结论 胰腺实性-假乳头状瘤有相对特征性的影像和病理学表现,术后预后较好。  相似文献   
104.
Objective To establish a colorectal cancer colostomy orthotopic transplantation mice model. Methods A colostomy was preformed in BALB/C nu-nu nude mice. After two weeks, when the stoma healed, tumor tissues developed from Lovo cells were implanted into the submucosa of the stoma. When tumor grew up to 5 nun, fluorouracil(5-FU, 20 mg/kg) was administrated by intraperitoneal injection. Tumor developed at the colostomy was observed and its biological characteristics and behaviour were evaluated. Results Colostomy was performed in 10 mice and stoma healed at two weeks. Ten colostomies developed detectable tumor in two to three weeks. Three to five weeks later, the tumors grew up to 5 mm. Survival time of mice injected with 5-FU was (15.2±3.7) weeks (ranged: 11-21 weeks), and the survival time of the no-treantment group was (12.3±2.8)weeks (ranged:9-19 weeks). The difference was statistically significant (P=0.001). The rate of mesenteric metastasis was 1/5 and 2/5 in the treatment and no-treatment group respectively. Conclusion Colostomy orthotopic transplantation mice model is an ideal mice model with the advantages of having high success rate, visualization of implanted tumor in living animal, long survival time and significant tumor response to common chemotherapeutic agent.  相似文献   
105.
目的 :观察高血压患者在监护拔牙过程中血压、心率、心电图变化及手术应激反应的年龄差异 ,探讨安全科学的监护方法。方法 :对 739例高血压患者监护拔牙的临床资料进行回顾性分析。观察高血压患者和不同年龄组高血压患者麻醉前、中、后 ,拔牙中、拔牙后 ,血压、心率变化。结果 :高血压组血压、心率比对照组显著增高、加快 (P <0 .0 1) ;80岁以上年龄组收缩压显著升高 (P <0 .0 1) ,4 9岁以下年龄组收缩压显著降低 (P <0 .0 5 ,P <0 .0 1)。结论 :各种高血压患者特别是高龄高血压患者 ,在分时安全管理下可以接受无痛拔牙。  相似文献   
106.
AIM:ToinvestigatethepathogenesisofAβ42yieldingandnewdrugtargetsaswellasthepossibilityofRNAinterference(RNAi)techniquefortreatmentofAlzheimerdisease(AD).METHODS:HumanADpresenilin1(PS1)cDNAsequencewasobtainedfromNCBIwebsite.ThethreesitesofRNAiactionandonemissensecontrolsitewereselectedinPS1cDNAthroughonlinedesignofAmbioncompany.Toconfirmspecificityofthesesites,weconductedaBLASTsearchoftheIMAGEESTlibrary.Thecorrespondingdouble-strandedDNAwasusedtoconstructpSilencer3.1-H1p…  相似文献   
107.
不同婴儿食品铝含量的测定   总被引:1,自引:0,他引:1  
本文应用原子吸收光谱法测定母乳、牛奶、奶粉及不同喂养方式婴儿血清中锌、铜、铁及铝含量。母乳中锌、铜、铁含量均较牛奶丰富,铝含量低于牛奶;奶粉中锌、铜、铁含量高于牛奶,与母乳无显著差异,铝含量高于牛奶。母乳、牛奶及奶粉喂养的贫血患儿血清铝含量无显著差异,均明显低于铝中毒的血清铝水平。  相似文献   
108.
The effects of combined use of earthworm extract(912)and HpD-laser on the produc-tion of reactive oxygen and the biosynthesis of DNA in S_(180) tumor cells were studied throughchemiluminescence measurement and[~3H]-TdR incorporation assay.The results showed that as com-pared with the control,the intensity of chemiluminescence emitted by tumor cells treatedsimultaneously with 912 and HpD-laser was enhanced more than ten-folds,while that treated with912 or HpD-laser alone was increased only 2~4 folds.The[~3H]-TdR incorporation into tumorcells of the former group was inhibited upto 74.1%,and that of the latter groups decreased onlyby 42.2% and 40.0%,respectively.In accordance with these biochemical changes,the ultrastructuraldamage of tumor cells of the former,combinedly treated group appeared to be the most serious.This suggests an additive effect of 912 with HpD-laser on tumor cells.In addition,if free radicalscavengers,such as catalase and superoxide dismutase,were added to the reaction systembefore chemiluminescence assay,the luminescent enhancement effect mentioned above was dramaticallyalleviated,implying the presence of O_2~ and H_2O_2 in the system.Therefore,as to the toxic effecton tumor cells,912 and HpD-laser are not only additive in efficiency,but also similar in theunderlying mechanism of action.  相似文献   
109.
18只犬切除右肾,钳夹左肾动脉60分的肾缺血模型,再灌注5小时。将动物随机分成对照组、川芎嗪组及维拉帕米组。观察尿量、菊糖清除率、利钠指数、平均动脉压及心率;再灌注5小时取肾组织作形态学检查。结果显示川芎嗪对肾功能及形态有保护作用,维拉帕米则无此作用,提示在手术中有肾缺血时以川芎嗪作为肾保护药物优于维拉帕米。  相似文献   
110.
视网膜色素变性的遗传分离分析   总被引:4,自引:0,他引:4  
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