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41.
The selective cyclooxygenase-2 (COX-2) inhibitor has been reported to have antiinflammatory, neuroprotective, and antioxidant effects in ischemia models. In this study, the authors examined whether a selective COX-2 inhibitor (celecoxib) reduces cerebral inflammation and edema after intracerebral hemorrhage (ICH), and whether functional recovery is sustained with longer treatment. ICH was induced using collagenase in adult rats. Celecoxib (10 or 20 mg/kg) was administered intraperitoneally 20 minutes, 6 hours, and 24 hours after ICH and then daily thereafter. Seventy-two hours after ICH induction, the rats were killed for histologic assessment and measurement of brain edema and prostaglandin E2. Behavioral tests were performed before and 1, 7, 14, 21, and 28 days after ICH. The brain water content of celecoxib-treated rats decreased both in lesioned and nonlesioned hemispheres in a dose-dependent manner. Compared with the ICH-only group, the number of TUNEL-positive, myeloperoxidase-positive, or OX42-positive cells was decreased in the periphery of hematoma and brain prostaglandin E2 level was reduced in the celecoxib-treated group. Celecoxib-treated rats recovered better by the behavioral tests at 7 days after ICH throughout the 28-day period, and the earlier the drug was administered, the better the functional recovery. Evidence of similar effects in an autologous blood-injected model showed that direct collagenase toxicity was not the major cause of inflammation or cell death. These data suggest that celecoxib treatment after ICH reduces prostaglandin E2 production, brain edema, inflammation, and perihematomal cell death in the perihematomal zone and induces better functional recovery.  相似文献   
42.
CT影像学评分预测急性胰腺炎病情及转归的研究   总被引:2,自引:0,他引:2  
目的 探讨CT影像学评分对急性胰腺炎病情和转归的预测价值。方法 回顾性分析入院后经CT检查的急性胰腺炎46例,按一定的规则对每例患进行CT影像学评分与分型,并与临床治疗中的有关资料进行对照。结果 46例患CT评分后获得:轻型24例,中型13例,重型9例。轻型患较重型住院日少、恢复顺利,中转手术及死亡率均以重型为高。结论 CT评分对急性胰腺炎病情及预后评估具有重要意义。  相似文献   
43.
44.
矽肺患者肺功能与血气分析   总被引:1,自引:0,他引:1  
以67名Ⅱ、Ⅲ期矽肺患做了肺功能(VC,FVC,FEV,FEV1/FVC,MVV,DLCO和血气分析(PaO2,PaCogm2,pH)。结果表明Ⅲ期矽肺肺功能较Ⅱ期矽肺降低,其中VC,FVC、MVV降低有显著差异,PaO2和pH随矽肺期别增加呈降低有显著差异。PaO2降低尤为明显,PaCO2呈增高趋势。肺功能与PaO2改变显著相关,与PaCO2和PH无相关关系。PaO2〈10kPa发生率与尘肺劳动  相似文献   
45.
46.
本文观察了从西宁地区(2260m)快速进入高海拔地区(3700m(5天)和4600m(10天)时,尿中微量蛋白的排泄变化,结果表明,在西宁地区尿中微量蛋白水平与平原无异,到达3700m时,尿中AIb排出明显增多(P<0.01),至4600m时AIb排出更多(与3700m相比P<0.001),IgM也有增多趋势,而世居藏族除AIb明显增多外,尿中IgM亦较西宁地区明显增高(P<0.05),作者以为尿中微量蛋白的排泄变化有高度和时间界限,发生机理可能与低氧环境所致的交感、肾上腺内分泌系统的应激反应以及血液流变学改变有关。  相似文献   
47.
用PowerPoint XP设计幻灯片元素动画效果的实践   总被引:6,自引:1,他引:5  
PowerPoint XP新特性中突出的就是其动画设计功能的加强。文中对新增加的与动画没计相关的功能使用要点结合实际作了较详细的叙述。  相似文献   
48.
手部创伤性骨关节缺损的处理   总被引:4,自引:0,他引:4  
治疗手部骨关节缺损常采用植骨内固定、关节融合、关节成形及关节置换等方法.为总结经验,对1989年以来101例手部创伤性骨与关节缺损进行分析。单纯掌、指骨缺损39例,行直接短缩对位,克氏针内固定6例,1例发主骨不连;对33例缺损较大者用自体骨块植入克氏针交叉内固定,部分病例同时植人RBX或异体骨粒,10例发生延迟愈合,余全部正常愈合。骨与关节部分或完全缺损62例,采用关节成形术46例,其中以肋软骨移植效果最好,骨膜移植次之,筋膜衬垫或硅胶膜植入法较差;行关节融合术11例.均达顺利融合;采用自体关节置换5例,均成活,术后关节活动度均>70°。我们认为:自体骨块植入克氏针交叉内固定,必要时植入RBX骨粒.是治疗手部创伤性骨缺损的有效方法。关节缺损应按关节的重要性,分别采用关节融合术、关节成形术或关节置换术。  相似文献   
49.
Effects of posts on dentin stress distribution in pulpless teeth.   总被引:5,自引:0,他引:5  
A finite element analysis was carried out to study the roles of posts in reducing dentin stress in pulpless teeth. Two-dimensional plane strain models of the midlabiolingual section of a human maxillary central incisor were first analyzed. The results showed that the gold alloy post reduced maximal dentin stress by as much as 30%. However, the integrity of the dentin was compromised and the effects of the post were likely to be exaggerated in such models. In an effort to correct for these problems, plane stress models with side plates and axisymmetric models were analyzed. Posts were found to reduce maximal dentin stress by only 3% to 8% when the teeth were subjected to masticatory and traumatic loadings in these latter models. Although posts reduced maximal dentin stress by as much as 20% when the teeth were loaded vertically, teeth such as incisors and canines normally are not subjected to vertical loadings. Thus the reinforcement effects of posts seem to be doubtful in these teeth.  相似文献   
50.
Laparoscopic nephrectomy was performed in 15 male pigs, the procedure was successful in 14. Extraction of the intact kidney through a 5-cm lower abdomen incision was done in 7 animals; complete destruction and evacuation of the kidney was accomplished by a round-knife suction device through a 1-cm port in another 7 pigs. Grossly, the specimen consisted of sausage-like tubular renal tissue and a small amount of tissue debris. Pathology revealed that the glomerular and tubular structures were well preserved, no interstitial hematoma could be found. Four ports were usually used, one 1-cm umbilical camera port, one 0.5-cm port for ureter traction, and two 1-cm working ports along the midclavicular line. All the pigs recovered uneventfully. The average operation time was 3 h 20 min. The application of endo-GIA (United States Surgical Corporation) for renal hilum reduced the operative time to 2 h 20 min. Complications included renal vein tear during endoclip application and cutting in the first case, mild subcutaneous emphysema in 2 cases. This first pig received exploratory laparotomy for the repair and ligation of the renal vein. No more major complications occurred with increasing experience. From this porcine experiment, we conclude that the combination of laparoscopy, a tissue destroyer and an endobag for the entrapment of kidney seem to be a promising technique for clinical nephrectomy.  相似文献   
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