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71.
目的探讨3H-TdR掺入法在进行SMMC-7721系细胞肿瘤药敏试验实验时的最佳实验条件.方法确定出3H-TdR掺入法药敏实验时的最适细胞浓度、最适实验药物浓度、3H-TdR掺入最适时间;在最适条件下采用3H-TdR掺入法测定肝癌SMMC-7721细胞株对临床常用的9种抗癌药物的敏感性.结果应用3H-TdR掺入法检测肝癌SMMC-7721细胞株药敏试验的最适实验细胞浓度为1×104个/孔,最适试验药物浓度为1×PPC,3H-TdR最适掺入时间为收集细胞前8 h;肝癌SMMC-7721细胞株对DDP、ADM、5-FU、CPT高度敏感,对MTX、VP-16、MMC、NVB低度敏感,对PYM不敏感.结论 3H-TdR掺入法可用于肿瘤药物敏感性测定并确定出它的最适实验条件.  相似文献   
72.
全国细菌药敏试验的室间质量评价   总被引:1,自引:0,他引:1  
目的:了解全国大中型医院细菌药敏试验(AST)状况,提高检测水平和质量。方法:定期向全国各参加评价实验室发放冻干标本,要求在规定时间内报告可疑感染的病原菌及其药敏结果,对回报结果给予数据统计、分析和评价。结果:2000年全国489个细菌室对常见耐药菌的检测正确率分别为:超广谱β-内酰胺酶63%(ESBLs);苯唑西林敏感金黄色葡萄球菌(MSSA)74%;苯唑西林耐药凝固酶阴性葡萄球菌(MRSCoN)48%;对青霉素不敏感肺炎链球菌7%;氨基糖苷类高水平耐药肠球菌95%;产β-内酰胺酶流感嗜血杆菌正确率35%。结论:通过细菌药敏试验的室间质量评价反映出我国的细菌耐药性检测水平急待提高。  相似文献   
73.
Summary. The aim of the present study was to establish a more differentiating indicator of plasma membrane integrity of spermatozoa than the classic version of the hypoosmotic swelling test according to Jeyendraan. Spermatozoa were prepared by density gradient centrifugation (90% Percoll) to select 'fertilization competent' spermatozoa only. After a second washing procedure sufficiently pure sperm cell suspensions were obtained. The volume distributions of these sperm cells were measured with a Coulter Counter at 25 °C after adaptation in 300 mosmolar NaCl solution resp. 150 mosmolar NaCl solution for 5 min. These volume distributions showed significantly different patterns for the isotonic and hypotonic stress situation in the simple salt solution. Moreover, the comparison of the response to hypoosmotic stress showed more than four reproducible characteristic patterns, promising well differentiated results for different sperm populations. The new method for the detection of hypoosmotic swelling effect might be a real and valuable functional parameter.  相似文献   
74.
Background: Malignant hyperthermia (MH) susceptibility is diagnosed using halothane-caffeine contracture testing of a muscle sample maintained at 37˚C. However, there has not been a systematic study that examines the effect of different temperatures on the response of normal muscle to halothane and caffeine. We hypothesized that altering bath temperature would modify the contracture responses.
Methods: We obtained muscle samples from 20 patients undergoing surgical procedures of the lower extremities. The samples were dissected into 245 bundles and the bundles were exposed to halothane 3% or incremental caffeine, according to the North American MH group protocol. Several bundles from each patient were simultaneously studied at four different temperatures (22˚C, 30˚C, 37˚C and 44˚C). Each bundle was studied at only one temperature, the muscle samples of 3 patients were simultaneously studied at all four temperatures for halothane and caffeine.
Results: Maximum contracture to caffeine (32 mM) was highest at 37˚C; however, at lower caffeine concentrations (2–4 mM), there was no consistent effect of temperature on contracture response. Likewise, temperature did not alter contracture responses to halothane. The extremes of temperature (22˚C and 44˚C) were associated with lack of twitch in response to electrical stimulation. For the bundles exposed to halothane at 22"C, the absence of a twitch was associated with the presence of a contracture, although these were never above the diagnostic threshold.
Conclusions: We conclude that temperature has little effect on responses of normal muscle to halothane and caffeine.  相似文献   
75.
Visual assessment of urethrovesical junction mobility   总被引:1,自引:1,他引:0  
The aim of the study was to compare visual assessment of anterior vaginal wall descent with the Q-tip test in evaluating urethrovesical junction mobility. One hundred and eleven patients with prolapse and/or urinary incontinence were examined in the supine lithotomy position with an empty bladder. Maximum straining Q-tip tests and maximum descent of the anterior vaginal wall were measured. Using each centimeter of descent as a cutoff value, the sensitivities, specificities and positive and negative predictive values were compared to those of the Q-tip test. As the cutt-off points were moved distally, specificity increased at the expense of sensitivity. There was no single cut-off point that provided adequate sensitivity and specificity to be clinically useful to replace the Q-tip test. It was concluded that visual assessment of anterior vaginal wall descent does not provide diagnostic accuracy and acceptable sensitivity and specificity to determine urethrovesical junction mobility. Other methods should be employed to assess support.Editorial Comment: Many clinicians claim that they can assess urethrovesical junction mobility visually and thus avoid employing other means, such as the Q-tip test, ultrasonography, bead-chain cystography or fluoroscopy. Montella et al. evaluate a technique of visual assessment of urethrovesical junction mobility based on the International Continence Society's Standardization of Terminology of Female Organ Prolapse and Pelvic Floor Dysfunction as compared to evaluation with the Q-tip test. Their results clearly indicate that this technique (measurement of the descent of point Aa) does not provide adequate sensitivity or specificity in determining urethrovesical junction descent compared to the Q-tip test. Although this technique was only compared to the Q-tip test and not all other modalities available, it is doubtful that visual assessment of anterior wall descent at any level would correspond to urethrovesical junction mobility, as is discussed very succinctly by the authors.  相似文献   
76.
在RPHI试验中,将VitK1或VitK3预先与HBsAg阳性血清作用后,再加抗HBs单克隆抗体诊断红细胞,可见红细胞呈圆点状沉淀,提示HBSAg与抗HBs的结合受到抑制,该抑制作用呈浓度依赖性.RPHI试验后的抗HBs单克隆抗体诊断红细胞,经洗涤后再与HBsAg阳性血清作用,仍出现明显凝集,表明VitK对HBsAg与抗HBs结合的抑制作用不是通过影响抗HBs而产生的。  相似文献   
77.
我们对本地区因不孕而就诊的220对夫妇作精子-宫颈粘液穿透试验(SCMPT),同时,作了宫颈粘液涂片并计数每100个鳞状上皮中的白细胞数,观察这两者的相关关系.结论:随着宫颈粘液中的白细胞数增加,穿透优良的比率下降(P<0.005).因而体外SCMPT评分结果与宫颈粘液中的白细胞增多相关.  相似文献   
78.
应用声振仪对1992年2个月~1993年6个月单胎36~43周妊娠孕妇150例进行了声音振动刺激试验(VAS-T)并与无负荷试验(NST)对照。对此结果VAS-T(+)146例,(-)4例,NST反应型96例,无反应型54例。NST无反应型预测价值8%,假阴性率92%。NST无反应型经声音刺激后50例成VAS-T(+)。VAS-T预测价值99.3%。NST有效率66%,VAS-T有效率99%。NST至少需做20min,VAS-T95%在3min内达到标准,最长15min。为避免NST假无反应型,应进行VAS-T。  相似文献   
79.
79只眼底病患眼的光照黄斑部试验(MPT)结果显示:中心性浆液性脉络膜视网膜病变、老年性黄斑变性渗出型和Rieger型中心性渗出性脉络膜视网膜病变患眼的光照黄斑恢复时间显著延长,其它黄斑部病变患眼也有不同程度的延长。本文结合眼底荧光血管造影和黄斑视野域值试验对光照黄斑部试验的机理进行了探讨。  相似文献   
80.
A simple standardized screening test (South Australian Motor Co-ordination Screening Test, SAM Test) was developed to screen for poor co-ordination in 5 year olds; This SAM Test, which can be used by teachers, nurses and doctors, has explicit pass/fail criteria and has classified correctly 90% of children. The McCarthy Motor Scales, which are time consuming and limited to use by psychologists, were used to categorize 60 poorly co-ordinated and 60 normal children. The 120 children thus selected were tested on 19 items covering gross and fine motor skills. Statistical analysis to determine which items best discriminated between the two groups found the following five gross motor items to be most effective: one leg balancing, hopping, heel-toe walking on line, jumping Over ribbon and dropping ball and catching.  相似文献   
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