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81.
本研究建立了大鼠气管上皮细胞体内-体外转化模型,大鼠气管内滴注苯并芘,三天后处死大鼠,消化气管上皮细胞,接种于无血清完全培养基。细胞形成集落后,换为选择培养基继续培养五周,统计转化率。结果显示,25mg/kg和50mg/kg的苯并芘可诱导大鼠气管上皮细胞转化及微核增加,用同样方法研究了煤焦沥青提取物,结果表明,剂量为8mg/kg和25mg/kg的煤焦沥青提取物能明显诱导大鼠气管上皮细胞转化。 相似文献
82.
3种氟喹诺酮类药物抗生素后效应的研究 总被引:40,自引:2,他引:38
应用AVANTAGF分析仪的光密度法测定了环丙沙星(CPLX)、氧氟沙星(OFLX)和氟罗沙星(FLRX)的抗生素后效应(PAE).结果表明氟喹诺酮类抗菌药物对革兰氏阳性球菌和革兰氏阴性杆菌均产生明显的PAE.并随抗菌药物浓度的增大、对受试菌的PAE逐渐延长.呈现了明显的浓度依赖性;3种抗菌药物对铜绿假单胞菌的PAE都较长.MIC均较小.显示了良好的杀菌效果:氯罗沙星对除金葡球菌之外的受试菌的PAE均比其它2药较长.PAE的存在提示在临床设计给药方案时.可适当延长给药间期.减少给药次数与剂量.仍能维持抗菌效果。 相似文献
83.
不同缺氧时间对大鼠肺循环改变的影响 总被引:7,自引:2,他引:5
为了解缺氧时间与肺动高压发生的关系,采用动物缺氧模型观察不同缺氧时间大鼠的肺血流动力学、右心室肥厚和肺血管结构等指标的变化。结果发现经缺氧处理后,大鼠肺动脉压于第3天开始升高,2周时达高峰;右心室重量在1周时明显增加;肺血管结构改变于3天时出现内皮细胞长、变性,并逐渐发生细胞外基质增多,1周时出现管壁增厚,以缺氧3周最为明显。由此提示在3周以内,缺氧时间的长短与大鼠肺循环的改变程度具有明显的相关性 相似文献
84.
目的:观察偏瘫患者早期床上训练的效果。方法:对58例脑血管意外致偏瘫患者随机分成2组:观察组30例,护理中指导早期床上体操训练;对照组28例,按常规护理。以上、下肢肌力和日常生活活动能力(ADL)为评价指标,于训练开始时、训练4周、训练8周各评价1次。结果:观察组训练4周、8周时患侧上肢肌力以及ADL水平明显增加,与对照组比较有显著差异(P<001)。患侧下肢肌力训练4周及8周时均增加,与对照组比较,4周时无明显差异(P>005),8周时有显著性差异(P<001)。结论:对早期偏瘫患者实施床上功能训练,不仅可以提高患者的生命质量,而且可以减少、甚至解除患者及家属的经济和精神负担。 相似文献
85.
纤维支气管镜胸膜腔检查对原因不明胸腔积液的诊断价值 总被引:2,自引:0,他引:2
为评价纤维支所管镜行胸膜检查在诊断原因不明胸腔积液中的价值,用纤维支气管镜对10例原因不明的胸腔积液患者进行胸腔检查。结果9例2检查后明确了病因,且无并发症,提示该法对于不明胸腔积液的诊断是一种阳性率高、安全、简便的检查方法。 相似文献
86.
Denise Haderski Sergey Nazarenko Chih-Min Cheng Anne Hiltner Eric Baer 《Macromolecular chemistry and physics.》1995,196(8):2545-2561
The crystallization behavior of coextruded microlayered sheets comprised of 657 alternating layers of polycarbonate (PC) and a miscible copolyester of mainly 1,4-cyclohexanedimethanol and terephthalic acid (KODAR) was investigated as a function of annealing time when the KODAR was crystallized isothermally from the glass at 195°C. Comparisons were made with crystallization of KODAR alone, and with crystallization of KODAR from melt blends with PC. The kinetics of crystallization and the morphology of the crystallized KODAR were characterized with differential scanning calorimetry, and by examination of thin sections microtomed from annealed specimens in the polarized light microscope and the transmission electron microscope. The growth rate of small, birefringent KODAR spherulites was non-linear, and was strongly affected by diffusion of PC into the KODAR layers. Diffusion of amorphous PC into the KODAR layers retarded nucleation and spherulite growth and decreased spherulite density. The effect became more pronounced as the KODAR layer thickness was reduced. Spherulities nucleated randomly throughout the KODAR layers in the PC/KODAR 20/80 (w/w) microlayer and grew rapidly to form a continuous layer of impinged spherulites. In contrast, spherulites in the PC/KODAR 40/60 and 60/40 microlayers nucleated and grew along the center of the KODAR layers where the KODAR concentration was highest. 相似文献
87.
卡介苗激活杀伤细胞抗膀胱肿瘤作用研究 总被引:1,自引:0,他引:1
为了进一步探讨BCG抗膀胱肿瘤的作用机理,采取15例膀胱肿瘤患者外周血单个核细胞(PBMC),置于含BCG或IL2的培养基中培养,计算扩增倍数,检测培养细胞抗自体及异体膀胱癌细胞活性。结果:卡介苗激活杀伤细胞(BAK)与淋巴因子激活杀伤细胞(LAK)分别于培养第7和第3天达增殖高峰,对自体瘤杀伤率分别为36.2%和31.4%,差异有显著性(P<0.05);对异体瘤杀伤率分别为25.2%和28.3%,差异无显著性。结果表明:BAK细胞抗自体瘤活性高于LAK细胞,死BCG对PBMC无激活作用,BAK细胞抗肿瘤效应可能是BCG抗膀胱肿瘤重要作用机理之一。 相似文献
88.
89.
Twenty-one patients, under 6 years of age, with root avulsion of the brachial plexus were treated from 1975 to 1987. Among them, 9 had root avulsion of the upper trunk, 2 root avulsion of the lower trunk with middle trunk broken, and 10 root avulsion of the whole brachial plexus. Follow-up of 16 patients showed excellent results in 2 patients, good in 11, fair in 1 and poor in 2. It is suggested that good results can be obtained if multi-paired nerve transfer is adopted in treatment. We conclude that owing to anatomical and physiological characteristics of the respiratory system in children, it is harmful to perform phrenic nerve transfer concomitantly with intercostal nerve transfer. Advisably, two-stage operation is required, otherwise dyspnea and pneumonia are liable to occur. In addition, the time of the operation could be extended to 4-5 years after injury in children, but best results are obtained if the operation is performed within 1 year.
相似文献
90.
CM Reid M. Nelson P. Beckinsale P. Ryan LMH Wing LJ Beilin MA Brown GLR Jennings CI Johnston J. Marley JJ McNeil TO Morgan J. Shaw ID Steven MJ West 《Clinical and experimental pharmacology & physiology》1997,24(5):370-373
1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial. 相似文献