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91.
Chlorotoxin, one of the key toxins in scorpion Leiurus quinquestriatus venom, has been shown to bind specifically to glioma cell surface as a specific chloride channel blocker. In this study, a purified, recombinant chlorotoxin-like peptide from the scorpion Buthus martensii Karsch (named rBmK CTa) was characterized by in vivo and in vitro studies. The results from cell proliferation assay with human glioma (SHG-44) cells showed that rBmK CTa inhibits the growth of glioma cells in a dose-dependent manner, with an IC50 value of approximately 0.28 μM. Under the same conditions, the IC50 value for normal astrocytes increased to 8 μM. This clearly indicated that rBmK CTa had specific toxicity against glioma cells but not astrocytes. Results from whole-cell patch-clamp recording showed that chloride current in SHG-44 was inhibited by rBmK CTa in a voltage-dependent manner and percent inhibitions for the blocking action of rBmK CTa (0.07 and 0.14 μM) on ICl was 17.64 ± 3.06% and 55.86 ± 2.83%, respectively. Histological analysis of rBmK CTa treated mice showed that brain, leg muscle and cardiac muscle were the target organs of this toxin. These results suggest that rBmK CTa may have potential therapeutic application in clinical treatment of human glioma. It represents an approach for developing a novel therapeutic agent.  相似文献   
92.
The vulnerability of epidemic process during the period of minimum annual incidence of the disease is validated. Biological properties of Shigella sonnei are studied and their variability examined using the index for evaluation of the mean number of variations for a sign. Minimum agent heterogeneity coincides with minimum incidence of disease and maximum heterogeneity with its seasonal rises.  相似文献   
93.
目的 观察经皮穿刺囊内注射消痔灵治疗肝囊肿的疗效。方法 回顾性分析58例肝囊肿患者(男18例,女40例;年龄16-78岁,平均39.5岁),行B超引导下经皮穿刺肝囊肿内注射消痔灵注射液的临床疗效。结果 58例随访10个月,总治愈率94.8%(55/58),显效率5.2%(3/58),总有效率100%。未出现感染、发热等。结论 B超引导下穿刺囊肿内注射消痔灵治疗肝囊肿疗效好,方法安全、简便、实用,患者易于接受。  相似文献   
94.
Five cases of primary sclerosing scrotal lipogranuloma were examined histologically and immunohistochemically. Every case lacked a history of injection or trauma, and revealed Common histologicat features; a typical granuloma composed of epithelioid cells and multinucleated giant cells, and inflammatory infiltrates of eosinophils, lymphocytes and macrophageimonocytes in the interstitium. lmmunahistochemistry disclosed the epithelioid cells and multinuclaated giant cells of the granuloma to be monocytetr in nature, as bath types of cells were positive for lyso-yme, α-1-antltrypin, α-1-antichymotrypsin, and KP-1. In the interstitium, KP-1 positive monocytes, L-26 positive B lymphocytes, UCHL-1 positive T lymphocytes and 5–100 protein positive Langerhans-like cells were frequently found. 5100 protein positive cells could not be detected in the granuloma. Primary sclerosing lipogranuloma of the scrotum, therefore, is a peculiar inflammation characterized by granulomas consisting of monocytes and marked tissue eosinophilia of unknown etiology.  相似文献   
95.
Clinical trials have demonstrated that buspirone (BuSpar) is effective in the treatment of anxiety with efficacy and dosage comparable to diazepam or chlorazepate. Buspirone has a unique structure and a pharmacologic profile which distinguishes it from the benzodiazepines. Because it lacks the anticonvulsant, sedative, and muscle-relaxant properties associated with other anxiolytics, buspirone has been termed "anxioselective." Animal studies suggest that it lacks potential for abuse, and this finding is supported by clinical investigations. Further preclinical work supports the contention that buspirone lacks liability to produce physical dependence or to significantly interact with central nervous system depressants such as ethanol. Moreover, biochemical investigations have not identified any direct interaction of buspirone with the benzodiazepine-gamma-aminobutyric acid-chloride ionophore complex. Pharmacologic studies on the molecular level indicate that buspirone interacts with dopamine and serotonin receptors. Recent behavioral, electrophysiological, and biochemical studies have clearly demonstrated that early hypotheses that buspirone might be considered a neuroleptic are no longer tenable. Recent evidence indicates that other neurotransmitter systems (serotonin, norepinephrine, acetylcholine) mediate buspirone's effects. It is hoped that future studies can define the mechanism by which buspirone alleviates the clinical manifestations of anxiety.  相似文献   
96.
A study to ascertain suitable conditions for handling biological samples from patients, treated with the antibiotic mitomycin C (MMC), with the objective of improving the accuracy and reliability of the determination is described. Situations frequently occurring in medical practice are simulated to optimize procedures for reliable and reproducible sampling, sample treatment and determination of MMC. Continuation of drug partitioning in whole blood after sampling can be prevented by immediate cooling in ice before the separation of plasma from cells. The adjustment of the pH of urine samples is shown to be particularly important since a low urinary pH causes decomposition of MMC; moreover, it may decrease extraction recovery. Furthermore, long-term exposure of samples to daylight induces drug decomposition. Frozen storage of plasma and urine samples for periods greater than 3 weeks is to be avoided as this results in a considerable drop in MMC concentration. Repeated cycles of freezing and thawing are shown to have no effect upon the analytical results (6 cycles tested). The analysis of extracts of biological samples may take place up to at least 24 h after their preparation without measurable loss of analyte.  相似文献   
97.
目的探讨全国尿标本分离细菌菌种分布及耐药变迁。方法按照全国细菌耐药监测网(CARSS)技术方案,应用WHONET5.6软件对2014—2019年所有CARSS成员单位上报的尿标本分离细菌及药敏结果数据进行分析。结果男性患者尿标本分离细菌居前5位者分别为大肠埃希菌(33.1%~34.6%)、粪肠球菌(9.2%~10.2%)、肺炎克雷伯菌(9.0%~9.4%)、屎肠球菌(7.8%~10.2%)和铜绿假单胞菌(5.6%~6.9%),女性患者尿标本分离细菌居前5位者分别为大肠埃希菌(57.0%~57.4%)、肺炎克雷伯菌(7.5%~8.3%)、屎肠球菌(6.8%~8.7%)、粪肠球菌(5.5%~6.0%)和奇异变形杆菌(3.3%~3.5%)。男性和女性患者尿标本分离粪肠球菌对氨苄西林和呋喃妥因耐药率分别<12%和7%,对万古霉素耐药率<3%;屎肠球菌对氨苄西林、左氧氟沙星耐药率均为90%左右,对万古霉素耐药率<4%。大肠埃希菌对头孢曲松耐药率>47%,对头孢哌酮/舒巴坦、哌拉西林/他唑巴坦、呋喃妥因耐药率≤8%,对于β-内酰胺类耐药率男性比女性高,其中头孢曲松的耐药率高12个百分点左右。男性患者分离肺炎克雷伯菌对头孢曲松耐药率为58%左右,女性患者耐药率为45%左右。男性和女性患者尿标本分离铜绿假单胞菌对头孢哌酮/舒巴坦和哌拉西林/他唑巴坦的耐药率均<14%,对碳青霉烯类耐药率为15%左右。鲍曼不动杆菌对头孢哌酮/舒巴坦和米诺环素耐药率分别<27%和22%,对碳青霉烯类耐药率,男性为31.7%~47.7%,女性为26.5%~41.2%。结论尿标本分离细菌在不同性别构成上有所不同,且部分肠杆菌目细菌耐药率不同性别间也有一定差异,不同年度间部分细菌的耐药率也有一定变化。尿标本分离细菌的耐药监测,可为尿路感染抗菌药物合理应用提供参考数据。  相似文献   
98.
 目的 了解全国粪便标本分离病原菌的菌群分布及耐药情况。方法 从2014-2019年全国细菌耐药监测网报告中提取粪便标本的相关数据(去除肠道正常定植菌群),分析肠道致病菌及其耐药率的变迁。结果 共分离菌株61 809株,居前3位的是沙门菌属(82.12%)、志贺菌属(8.08%)、弧菌属(4.03%),沙门菌属在每年粪便标本致病菌中占绝对优势,均在70%以上,以2018年占比最高(87.16%)。6年间居前6位的致病菌菌种无变化,仅菌种构成比每年略有变化,沙门菌属呈上升趋势,志贺菌属呈下降趋势。各菌属分别以未分型沙门菌(49.39%)、福氏志贺菌(46.64%),副溶血弧菌(91.20%)、嗜水气单胞菌(55.80%)、肠致病性大肠埃希菌(85.02%)为主。肠道致病菌对氨苄西林耐药率均较高,其中志贺菌属和致腹泻性大肠埃希菌(>90%)高于沙门菌属和弧菌属。沙门菌对左氧氟沙星耐药率较低,但呈上升趋势,由低于3%上升至10%左右;志贺菌属对环丙沙星耐药率2016年较低(29.9%);除氨苄西林外,弧菌属对其他抗菌药物耐药率均较低(<6%);气单胞菌属出现了耐碳青霉烯类菌株,气单胞菌属和致腹泻性大肠埃希菌对阿米卡星耐药率较低。结论 细菌性腹泻的病原菌种类较多,以沙门菌属和志贺菌属为主,耐药情况较为严重,且不同菌属、菌种之间差异较大,应继续加强抗菌药物合理应用的管理及医院感染防控,做好耐药菌监测工作。  相似文献   
99.
复方磺胺嘧啶锌涂膜剂治疗烧伤的疗效观察   总被引:6,自引:1,他引:5  
目的 观察复方磺胺嘧啶锌涂膜剂治疗浅Ⅱ度、深Ⅱ度 烧伤创面、残余创面抗感染和促进创面愈合的作用。方法 治疗组清 创 后应用复方磺胺嘧啶锌涂膜剂涂于创面的表面,对照组应用1%磺胺嘧啶银霜覆盖创面,共治 疗119例烧伤患者(即222个创面),包括浅Ⅱ度烧伤、深Ⅱ度烧伤、残余小创面及供皮区创面 ,并观察创面完全愈合时间、创面表面细菌培养用药前与用药中的情况以及复方磺胺嘧啶锌 涂膜剂对全身情况的影响。结果 浅Ⅱ度烧伤创面治疗组(10.25±1 .6 9)天完全愈合,对照组(13.15±2.03)天愈合;深Ⅱ度创面治疗组(18.10±2.72)天愈合 ,对照组(21.2±3.64)天愈合,治疗组明显优于对照组(P<0.05);治疗组用药前细 菌培养阳性率是38.8%,治疗中降至9.0%;对照组用药前细菌培养阳性率为32.7%,治疗 中降至25.4%;两组间比较具有显著性差异(P<0.05);患者未出现疼痛、过敏反应 和其它不良反应。结论 复方磺胺嘧啶锌涂膜剂治疗烧伤创面可促进上 皮 化、加速创面愈合、有效地防治创面感染,该药应用简便、适用于社区、基层常见的中、小 面积浅度烧伤治疗。  相似文献   
100.
周英琼  邱维加  曾青  黄勤 《华夏医学》2001,14(2):121-123
目的 :研究高、低渗造影剂对甘油致肾损害大鼠和正常大鼠的肾毒性 ,观察山莨菪碱预防肾小管损害的作用。方法 :用 2 5 %甘油按 1ml/ 10 0 g制肾损害大鼠模型 ,然后从静脉注射高渗造影剂 (76 %复方泛影葡胺 ,1ml/ 10 0 g)或优维显 (1m l/ 10 0 g) ,2 4h后各组随机处死 10只大鼠 ,肾脏用 10 %福尔马林固定后做病理检查。结果 :在肾功能损害组 ,给高渗造影剂后 ,可使肾小管管型数和肾小管坏死数明显高于低渗造影剂组和甘油对照组 (P<0 .0 1) ,山莨菪碱可明显减轻肾小管损害 (P<0 .0 5 )。正常肾功能组高、低渗造影剂组之间肾小管损害无显著性差异。结论 :肾功能损害时用低渗造影剂对肾毒性较小 ,山莨菪碱对复方泛影葡胺的肾毒性有一定的预防作用。  相似文献   
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