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排序方式: 共有10000条查询结果,搜索用时 203 毫秒
101.
Bradley J Catalone Shendra R Miller Mary Lee Ferguson Dan Malamud Tina Kish-Catalone Nina J Thakkar Fred C Krebs Mary K Howett Brian Wigdahl 《Biomedicine & Pharmacotherapy》2005,59(8):430-437
C31G, which has potent activity against the human immunodeficiency virus type 1 (HIV-1) and an established record of safety in animal studies and human trials, is a microbicidal agent comprised of a buffered equimolar mixture of two amphoteric, surface-active agents: an alkyl amine oxide (C14AO) and an alkyl betaine (C16B). Studies of long-term in vitro exposure to C31G and its constituents have suggested that the components of C31G may contribute differentially to its toxicity and efficacy. In the present studies, in vitro assays of cytotoxicity and anti-HIV-1 activity demonstrated that C16B was slightly less cytotoxic compared to either C31G or C14AO, whereas the anti-HIV-1 activities of C31G and its individual constituents were similar. In the murine model of cervicovaginal microbicide toxicity, in vivo exposure to C14AO resulted in severe cervical inflammation followed by a delayed disruption of the columnar epithelium. In contrast, exposure to C16B caused severe cervical epithelial disruption and a secondary, less intense inflammatory response. These results demonstrate that (i) there are both mechanistic and temporal differences in toxicity associated with the components of C31G not necessarily predicted by in vitro assessments of cytotoxicity and (ii) contributions of each component to the anti-HIV-1 activity of C31G appear to be equal. In addition, these findings indicate that direct and indirect mechanisms of in vivo toxicity can be observed as separate but interrelated events. These results provide further insight into the activity of C31G, as well as mechanisms potentially associated with microbicide toxicity. 相似文献
102.
肩关节周围炎的循证针灸治疗 总被引:3,自引:0,他引:3
目的:从循证医学的角度,向临床医生介绍肩关节周围炎的循证针灸治疗方案的确立方法.方法:以一位具体的肩关节周围炎患者为例,介绍如何提出临床问题,怎样检索相关文献,如何对所检索的文献进行评价,如何结合本病例的具体情况和医生的个人经验,运用所检索的证据拟定治疗方案.结果:采用按照循证医学方法确立的肩关节周围炎的针灸治疗方案治疗15次后,患者生活质量明显好转.结论:通过临床提出问题、寻找证据、分析证据、循证决策、循证实践过程,不但患者可达到满意疗效,主管医生也提高了理论水平和临床能力. 相似文献
103.
104.
硬胶囊剂系指将一定量的药材提取物,药材提取物加药材细粉或辅料制成的均匀粉末或颗粒,充填于空心胶囊中制成,或将药材细粉直接充填于空心胶囊中制成.通常由中药复方制成胶囊剂,其药料最后常制成18~22目颗粒再充填于胶囊中,制成颗粒是为了增加药料的流动性,并减少充填时的粉末飞扬.我们在制备本院协定处方制剂“消渴安胶囊”、“仙灵胶囊”、“愈胃胶囊”及“脑立通胶囊”等时,发现整粒后的药料如果烘干后立即充填胶囊,以及粉性成分较多的药料如果按常规工艺制粒、整粒,烘干后进行充填胶囊,均会出现药料吸附性较强,充填中出现“沾盘”现象,对上述两种情形我们进行了多次工艺摸索,最终较好地解决了上述药料吸附问题,现介绍如下. 相似文献
105.
106.
107.
目的评价屈颈MRI对青年性上肢远端肌萎缩症的诊断价值。方法男性患者5例,平均年龄21岁,临床表现为一侧或两侧上肢远端肌萎缩。对照组为健康志愿者,21岁男性8例。2组均行常规及屈颈颈椎MR平扫,矢状、轴面SET1WI、T2WI、液体衰减反转恢复(FLAIR)序列扫描。结果常规颈椎扫描:5例患者下段颈髓变细;屈颈位MR扫描:下颈段颈6以下脊髓前屈、变扁平,矢状径4~6mm,硬膜囊后壁前移,硬膜后间隙明显增宽,可见多发条状、迂曲流空信号影及软组织信号。对照组:常规扫描,下颈段脊髓(颈6~胸2)可见颈膨大,屈颈位脊髓略变细(6~7mm),硬膜囊后壁无前移,硬膜后间隙未见扩张血管影。结论屈颈MRI有助于显示下颈段脊髓及硬膜囊改变,结合临床资料可准确诊断青年性上肢远端肌萎缩症。 相似文献
108.
聚磷酸钙纤维和左旋聚乳酸软骨支架复合自体骨髓间充质干细胞构建组织工程化人工关节软骨 总被引:1,自引:0,他引:1
目的应用组织工程学技术,体外初步构建组织工程化人工关节软骨。方法制备三维多孔软骨支架材料CPP/PLLA,体外诱导兔MSCs向软骨细胞表型分化,免疫组织化学染色检测软骨特异性Ⅱ型胶原表达,将诱导细胞与软骨支架材料CPP/PLLA复合,体外培养构建人工关节软骨,1周后终止培养,扫描电镜观察组织工程化人工软骨的微观结构;同时将构建人工软骨移植于兔大腿皮下,3周后处死动物,甲苯胺蓝染色观察。结果扫描电镜观察可见该复合材料CPP/PLLA为高孔隙率的网状、连通、微孔结构,微孔分布均匀,孔径大小为300~400Ⅳn之间;兔MSCs经体外软骨表型定向诱导后,Ⅱ型胶原免疫组化染色阳性。诱导后的MSCs可在支架材料内良好贴附生长,细胞被分泌的胶原基质包裹;从体内获取的培养物组织切片观察可见大量的软骨细胞生成,甲苯胺蓝染色阳性。结论经软骨起源诱导后的MSCs与CPP/PLLA复合培养可以构建自体软骨移植的替代物,为应用软骨组织工程方法修复关节软骨缺损和功能重建提供一种新材料,具有较大的潜在应用价值。 相似文献
109.
危重患者经外周静脉置入中心静脉导管的临床研究——前瞻性随机对照研究 总被引:3,自引:0,他引:3
目的 比较经外周静脉置入中心静脉导管(peripherally inserted central catheter,PICC)与经锁骨下静脉中心静脉置管在危重患者中的临床应用.方法 通过前瞻性随机对照研究方法,将80例ICU危重患者分为PICC组(40例)和锁骨下静脉组(40例),观察两组穿刺成功率、穿刺时间、穿刺不良反应发生率等.结果 PICC组较锁骨下静脉组一次穿刺成功率高(92.5%vs 75.0%,χ2=4.501,P=0.034),穿刺时间短[(15.7±5.3)min vs(23.9±6.3)min,t=-6.263,P=0.000],总不良反应发生率低(10.0%vs 27.5%,χ2=4.021,P=0.045).结论 PICC穿刺简便易行,危险性小,在危重患者中PICC置管优于锁骨下静脉置管. 相似文献
110.
BACKGROUND: As a non-invasive technique which can provide comprehensive biological information, 1H-magnetic resonance spectroscopy (1H-MRS) may provide valuable reference data for irreversible recovery or reversible changes in ischemic tissue after stroke.
OBJECTIVE: To monitor and evaluate the effect of the urokinase thrombolytic therapy after experimental acute cerebral ischemia by 1H-MRS technology and investigate its adaptability.
DESIGN: Randomly controlled animal study.
SETTINGS: Shenzhen Hospital of Peking University and National Key Laboratory of Pattern and Atom & Molecular Physics, Wuhan Physics and Mathematics Institute, Chinese Academy of Science.
MATERIALS: Eleven healthy adult Sprague-Dawley (SD) rats, weighing 260–300 g and of both genders, were supplied by Experimental Animal Center of Tongji Medical Collage, Huazhong University of Science and Technology [SCXK (e) 2004-007]. 4.7T superconducting nuclear magnetic resonance meter was provided by Brucker Company.
METHODS: The experiment was carried out in Shenzhen Hospital of Peking University and National Key Laboratory of Pattern and Atom & Molecular Physics, Wuhan Physics and Mathematics Institute, Chinese Academy of Science from August 2003 to December 2005. ① The rats were randomly divided into 30-minute self-thrombo-embolism group (n =6) and 60-minute self-thrombo-embolism group (n =5). Six rats in 30-minute self-thrombo-embolism group were occluded with clot embolus for 30 minutes and 5 rats in 60-minute self-thrombo-embolism group were occluded for 60 minutes. 10 000 U/kg urokinase was dissolved in 2 mL saline and the operation lasted for 5 minutes. ② 1H-MRS was performed before thrombolysis and at 3 hours and 24 hours after successful embolization. The metabolic changes of N-acetyl-L-aspartic acid (NAA)/phosphocreatine (PCr) + creatine (Cr), choline phosphate (Cho)/PCr+Cr and lactic acid (Lac)/PCr+Cr in the region of interests were analyzed. ③ The T2W image was conducted 24 hours after the thrombolytic therapy with TR=500 ms and TE=25 ms. ④ The subjects were sacrificed immediately after 1H-MRS and the brain tissues were cut into pieces and stained with HE method; in addition, pathological changes were observed under optic microscope.
MAIN OUTCOME MEASURES: ① Metabolic changes of NAA/PCr+Cr, Cho/PCr+Cr and Lac/PCr+Cr in the region of interests; ② T2W image at 24 hours after the thrombolysis; ③ pathological observation of brain tissue.
RESULTS: Eleven rats were all involved in the final analysis. ① Metabolic changes in the region of interests : In 30-minute self-thrombo-embolism group, the Lac peak emerged immediately after the embolism, but the ischemic zone decreased 3 hours after the thrombolytic therapy (0.252±0.01, 0.603±0.01, P < 0.01). Lac/(PCr+Cr) ratio was 0.290±0.01 at 24 hours after thrombolysis, which was higher than that at 3 hours after thrombolysis (P < 0.01). The NAA/ (PCr+Cr) ratio decreased significantly at 3 hours after the thrombolysis as compared with that before thrombolysis (0.922±0.16, 1.196±0.01, P < 0.05). In 60-minute self-thrombo-embolism group, the Lac/(PCr+Cr) ratio was higher at 3 hours after thrombolysis than that before thrombolysis (0.846±0.12, 0.601±0.11, P < 0.05) and the NAA/(PCr+Cr) decreased at 3 hours after the embolism. Fluctuation of NAA/ (PCr+Cr) ranged from 0.68 to 0.75 before thrombolysis and from 0.71 to 0.75 at 3 hours after thrombolysis. ② T2W image: T2W image showed that 2 subjects in 30-minute self-thrombo-embolism group whose Lac/NAA was higher than 0.7 suffered from intracranial hemorrhage. This meant that the subjects with Lac/NAA > 0.7 were more likely to suffer from intracranial hemorrhage. ③ Histological and morphological examinations: Optic microscope demonstrated that interspace surrounding nerve cells was widened at ischemic center; neurons were swelling; nucleus was stained lightly; pyknosis and mesenchymal edema were mainly observed in lateral cortex of brow and vertex and in lateral part of corpus striatum.
CONCLUSION: ①Compound parameters in ischemic area before thrombolysis should be regarded as an important predicting marker for thrombolytic therapy, effect evaluation and termination. ② 1H-MRS combining with other imaging technique is a detecting way for screening cases who are suitable for thrombolytic therapy. 相似文献