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121.
目的:探讨顺铂作用于卵巢癌细胞的作用机理。方法:通过电镜、光镜、流式细胞仪等方法观察顺铂诱导人亲代和耐药卵巢癌细胞COC1 、COC1/DDP凋亡,进行细胞周期分析及计算凋亡率。结果:顺铂引起细胞S期增多、S期细胞凋亡,COC1 、COC1/DDP细胞凋亡率不同。结论:顺铂药理机制之一是诱导细胞凋亡,耐药与凋亡减少有关。  相似文献   
122.
应用荧光试剂(33258Hoechst)微量测定细胞内DNA含量,应用荧光胺(Fluorescamine)微量测定细胞内蛋白质含量。结果:荧光试剂与DNA的A-T碱基形成复合物后,其激发波长(EX)由320nm移至350nm,发射波长(EM)由480nm移至460nm,且荧光强度大为增强。荧光胺与蛋白质反应生成强荧光化合物,在EX390nm,EM475nm条件下最低检测限为0.5μg/μl。该法操作简便,微量快速,重复性好。可用于荧光微量测定DNA与蛋白质含量,还可用于观察细胞的增殖。  相似文献   
123.
为了能够精确地建立轻、中、重液压冲击分级脑损伤动物模型,我们设计了侧位液压冲击脑损伤装置。该装置由不锈钢储液管、压缩空气、减压设备及计算机等组成,可以精确地控制冲击气压的大小、记录冲击时脑组织所承受的压力、显示压力曲线、液压冲击后可以迅速释放系统内的压力,国内、外均未见报道。侧位液压冲击脑损伤随冲击压力的增加而加重,以冲击侧大脑半球为最重,也可波及对侧及脑底部。  相似文献   
124.
目的:探讨骨肉瘤保肢治疗中肿瘤大小、临床分期、手术方式、术前、术后化疗以及肿瘤多药耐药基因(mdr)表达产物P糖蛋白(P-170)对术后生存时间的影响。方法:统计分析近7年47例骨肉瘤保肢术患者的病理、临床资料及生存时间,并用链菌素生物素标记法(LSAB)免疫组织化学法回顾性检测肿瘤标本中P-170糖蛋白。结果:临床分期为ⅡB期患者1~5年生存率分别是974%,760%,463%,389%和340%;ⅡA期患者相应的生存率为100%,800%,800%,800%和800%;ⅠB期患者相应的生存率皆为100%;各临床分期间的生存率有统计学差异(P<01)。术前有化疗的患者1~5年生存率分别是975%,845%,674%,571%和530%;术前无化疗的患者相应的生存率分别为857%,429%和0%;两组生存率有统计学意义(P<001)。术后有化疗的患者1~5年生存率分别是971%,942%,727%,616%和572%;术后无化疗的患者相应的生存率分别是90%,200%和0%;差异有统计学意义(P<001)。P-糖蛋白阳性组1~5年生存率分别是974%,733%,471%,359%和307%;P-糖蛋白阴性组的相应值皆为100%,差异有统计学意义(P<001)。此外,在不同保肢术式中人工关节置换术患者1~5年生存率最高,分别是967%,930%,700%,631%和520%,差异有统计学意义(P<001)。结论:肿瘤临床分期、肿瘤大小、保肢术式、术前、术后化疗及P-17  相似文献   
125.
BACKGROUND AND PURPOSE: MR imaging has revealed putative evidence of subclinical cerebrovascular disease (CVD) as reflected by white matter signal changes and infarct-like lesions (ILLs). Nonetheless, the prevalence of this condition in the general population has been defined only to a limited extent. We herein report the prevalence and anatomic characteristics of ILLs seen on cranial MR images obtained as part of a population-based study of cardiovascular disease in middle-aged adults. These results are contrasted to those of previous similar studies, particularly those of an elderly population in the Cardiovascular Health Study (CHS). METHODS: This Atherosclerosis Risk in Communities (ARIC) cohort consists of a probability sample of community-living persons who were 55 to 72 years old at the time of MR examination. MR imaging of 1890 participants was performed at two ARIC field centers, based on a common protocol. MR studies were evaluated by trained readers at the MR Reading Center using original digital data displayed on a high-resolution workstation. The measures of lesion size, anatomic location, and signal intensity were collected. The definition for an ILL was a non-mass, hyperintense region with an arterial vascular distribution on spin-density and T2-weighted images. RESULTS: Two hundred ninety participants had ILLs, for an overall prevalence of 15.3%. Eighty-two percent of participants with ILLs had lesions that were 3 mm or larger in maximal dimension, although 87% of these lesions were 20 mm or smaller in maximal dimension. The prevalence of ILLs increased with age, from 7.9% in the 55- to 59-year-old age group to 22.9% in the 65- to 72-year-old age group (P < .001). Lesion prevalence was greater in black (20.7%) than in white persons (10.2% [P < .0001]), but did not differ significantly between male and female participants. The basal ganglia and thalamic region was the most commonly affected anatomic site, accounting for 78.9% of the lesions. CONCLUSION: Considering that the prevalence of self-reported stroke or transient ischemic attack in ARIC participants is 1.5%, these results suggest that there is significantly more subclinical than clinical CVD in the general population. Furthermore, the prevalence of this subclinical disease increases with age, and is greater in black persons. ILLs are dominated by "lacunae" in the basal ganglia and thalamus. These results are, in general, similar to those of a comparable study of elderly participants in the CHS, except for a 60% lower prevalence of ILLs in this younger population.  相似文献   
126.
Aim: To study the behavior of external urethral sphincter in chronic prostatitis (CP) patient under natural filling.Methods: Twenty-one CP patients and 17 normal volunteers were involved in the study. Both the patients andvolunteers underwent ambulatory urodynamic monitoring (AM) and conventional medium filling cystometry (CMG).Urodec 500 was used for AM and Menuet for CMG. AM findings from CP patients were compared with those fromnormal volunteers, and the results from AM were compared with those from CMG. Results: In AM, the restingand voiding external urethral sphincter (EUS) pressures and maximum urethral closure pressures (MUCP) weresignificantly higher in CP patients [ ( 121.5 ±10.3) and (85.6±3.5) cm water, respectively ] than in normalvolunteers [ (77.6±11.4) and (10.3±1.6) cm water, respectively)]. Conclusion: The behavioral changes ofEUS in CP patients included spasm and instability of EUS, which were demonstrated using AM under natural filling;the findings were also in accord with the res  相似文献   
127.
BACKGROUND AND PURPOSE: Neutrophil (PMN) recruitment mediated by increased expression of intercellular adhesion molecule-1 expression (ICAM-1, CD54) in the cerebral microvasculature contributes to the pathogenesis of tissue injury in stroke. However, studies using blocking antibodies against the common beta2-integrin subunit on the PMN, the counterligand for ICAM-1 (CD18), have demonstrated equivocal efficacy. The current study tested the hypothesis that mice deficient in CD18 would be protected in the setting of reperfused but not nonreperfused stroke. METHODS: Two groups of mice were studied, those whose PMNs could express CD18 (CD18 +/+) and those mice hypomorphic for the CD-18 gene (CD18 -/-). PMNs obtained from CD18 -/- or CD18 +/+ mice were fluorescently labeled and tested for binding to murine brain endothelial monolayers. Using a murine model of focal cerebral ischemia in which an occluding suture placed in the middle cerebral artery (MCA) is removed after 45 minutes (transient ischemia, reperfused stroke) or left in place (permanent ischemia, nonreperfused stroke), cerebral infarct volumes (% ipsilateral hemisphere by TTC staining), cerebral blood flow (CBF, % contralateral hemisphere by laser-Doppler flowmetry), and survival (%) were examined 24 hours after the initial ischemic event. Adoptive transfer studies used 111In-labeled PMNs (from either CD18 +/+ or CD18 -/- mice) to examine the relative accumulation of PMNs in the ischemic region. RESULTS: PMNs obtained from CD18 -/- mice exhibit reduced adhesivity (compared with CD18 +/+ PMNs) for both quiescent and cytokine-activated endothelial monolayers. CD18 -/- mice (n=14) subjected to transient focal cerebral ischemia demonstrated a 53% decrease in infarct volumes versus CD18 +/+ mice (n=26, P<0.05), improved penumbral CBF at 24 hours (1.8-fold, P=0.02), and a 3.7-fold decrease in mortality (P=0.02). However, when CD18 -/- mice (n=12) were subjected to permanent focal cerebral ischemia, no differences were noted in infarct volume, mortality, or CBF versus similarly treated CD18 +/+ mice (n=10). There was a greater accumulation of CD18 +/+ PMNs in the ischemic zone of CD18 +/+ animals than CD18 -/- animals subjected to reperfused stroke (82% increase, P=0.02), although there was no difference between groups when subjected to permanent MCA occlusion. CONCLUSIONS: Deficiency for the CD18 gene confers cerebral protection in a murine model of reperfused stroke, but this benefit does not extend to CD18-deficient animals subjected to permanent MCA occlusion. These data suggest that anti-PMN strategies should be targeted to reperfused stroke and may perhaps be used in conjunction with thrombolytic therapy that establishes reperfusion.  相似文献   
128.
Zhao Y  Liao Q  Zhu Z  Fu Q  Cai L  Zhu Y 《中华外科杂志》1999,37(3):144-145
探讨5-氟尿嘧啶能否通过胰十二指肠切除术后的残留胰腺组织进入胰液中,并达有效的治疗浓度,为胰腺为临床合理化疗提供理论依据。方法通过观察胰十二指肠切除术患者胰快速推注5-氟尿嘧啶后血液和胰液中药物动态分布及相关性,术后静脉一次性快速推注5-氟尿嘧啶1.0g/m^2,在给药前后按设计时间点分别采集静脉血和胰液,采用高效液相色谱法测定血浆和胰液5-氟尿嘧啶药物浓度,应用PCNONLIN程序程序计算共动态  相似文献   
129.
Shan G  Wang X  Qiu C  Ren C  Li H  Wang P  Wu Z  Liao S  Li X  Tong S  Zhang K 《中华预防医学杂志》1999,33(6):346-347
目的 探讨血管紧张素转换酶(ACE) 基因多态性与高血压的关系。方法 应用横断面调查方法和PCR 技术。结果 正常血压人群ACE 基因DD、ID 和II基因型分别占13 .0 % 、50 .9 % 和36 .1 % 。I和D等位基因频率分别是为61 .6 % 和38 .4 % 。高血压人群ACE 基因DD、ID 和II基因型分别占9 .7 % 、48 .4 % 和41 .9 % 。I和D 等位基因频率分别是66 .1 % 和33 .9 % 。彝族男性高血压和正常血压人群的ACE基因型分布及I/D 等位基因频率差异无显著性。结论 彝族男性ACE 基因多态性与高血压的关联尚不能确定。  相似文献   
130.
自体角膜缘移植治疗翼状胬肉的临床观察   总被引:10,自引:0,他引:10  
朱美玲  李峻岭 《眼科研究》1999,17(6):493-494
目的 探讨自体角膜移植治疗翼状胬肉的疗效。方法 对42例(48只眼)初发性和复发性翼状胬肉行自体角膜缘移植术,术后随访36例(42只眼),随访时间4个月~2年,平均9个月。结果 上皮愈合良好、稳定,无新生血管及结产生,角膜光滑,未见复发。结论 自体角膜缘移植可通过提供新的干细胞来源,提高翼状胬肉手术的成功率,降低术后的复发率,是一种有推广价值的手术方法。  相似文献   
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