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41.
PURPOSE: For cancer patients receiving cytotoxic chemotherapy, hepatitis B virus (HBV) reactivation is a well described complication resulting in varying degrees of liver damage. The objectives of this study were to assess the efficacy of the antiviral agent lamivudine in reducing the incidence of HBV reactivation and diminishing morbidity and mortality of cancer patients with chronic HBV infection during chemotherapy. PATIENTS AND METHODS: Two groups were compared in this nonrandomized study. The prophylactic lamivudine group consisted of 65 patients in a phase II study who were treated with lamivudine before and until 8 weeks after discontinuing chemotherapy. The historical controls consisted of 193 consecutive patients who underwent chemotherapy without prophylactic lamivudine. Significant prognosticators for the development of HBV reactivation were determined based on data from the controls. Potential confounding factors were identified between the two groups. The outcomes were compared. RESULTS: In the controls, lymphoma and anthracycline usage were factors identified to be associated with reactivation. The two groups were comparable in most baseline characteristics, although in the prophylactic lamivudine group, there were significantly more patients with lymphoma and receiving anthracyclines. In the prophylactic lamivudine group, there was significantly less HBV reactivation (4.6% v 24.4% in the controls; P <.001), fewer incidences of hepatitis (17.5% v 44.6%; P <.0001) that were less severe (4.8% v 18.7%; P =.0005), and less disruption of chemotherapy (15.4% v 34.6%; P =.0029). The reduction in overall mortality was not statistically different. CONCLUSION: Prophylactic lamivudine significantly reduced the incidence of HBV reactivation and the overall morbidity of cancer patients undergoing chemotherapy.  相似文献   
42.
消瘀散消肿止痛作用的实验观察   总被引:2,自引:2,他引:2  
消瘀散在临床运用中有较好的消肿止痛之功效.为了证实其药理作用,作者用大白鼠建立急性软组织损伤和血肿的实验模型,使用消疾散进行治疗。观察结果表明该药能够有效抑制创伤性无菌性炎症反应,促进血肿吸收,提高实验动物的痛阈值;而且药效随作用时间的延长而逐渐增加。实验结果为该药的消肿止痛作用提供了科学依据。  相似文献   
43.
目的:观察N-(4-羟苯基)维甲酰胺(4-HPR)联合γ-射线对人膀胱移行细胞癌的生长抑制和诱导凋亡作用,分析两者之间是否存在协同作用.方法:应用四甲基偶氮蓝比色(MTT)法检测4-HPR对膀胱癌细胞株T24的细胞毒性作用、半数抑瘤率及起效浓度和时间.应用流式细胞仪检测4-HPR、γ-射线及两者联合应用时对T24细胞生长抑制作用.结果:2.5μmol/L、5μmol/L、10μmol/L的4-HPR作用T24细胞5天的凋亡率分别为6.2%、28.0%和26.0%,死亡率分别为0.3%、12.5%和26.7%.联合作用组细胞分别加入2.5μmol/L、5μmol/L的4-HPR,100cgy的γ-射线照射一次,3天后T24细胞的凋亡率分别为20.0%、26.0%,细胞的死亡率均在5.0%以下.5天后T24细胞的凋亡率分别为38.0%、35.0%,而细胞的死亡率分别为12.4%、21.1%.结论:小剂量的4-HPR可以诱导T24细胞凋亡,大剂量的4-HPR主要导致T24细胞死亡.小剂量的4-HPR联合小剂量的γ-射线对T24细胞凋亡有明显的协同作用.  相似文献   
44.
目的了解马根维显(Gd-DTPA)动态增强核磁共振(MRI)评估肾积水术后疗效的应用价值。方法单侧肾积水患者11例,年龄7~42岁,平均19.5岁,均为男性;左侧肾积水9例,右侧2例;病因经静脉尿路造影(intravenousurography,IVU)和B超确诊,10例为先天性肾盂输尿管连接部狭窄(pelvicureterjunctionobstruction,PUJO),1例为输尿管中段慢性炎症所致不完全性梗阻;10例PUJO实施狭窄部成形术,另1例施行输尿管狭窄段切除并输尿管端端吻合术。应用Gd-DTPA作为对比剂,分别在术前1个月和术后3个月实施动态增强MRI检查,选取肾实质、肾盂和集合系统的类圆形区域作为兴趣区(regionofinteresting,ROI),计算不同时间点不同兴趣区的信号强度(signalintensity,SI)和相对信号强度(relativeSI,RSI),绘制T-SI曲线,对术前术后肾脏的形态和功能状态进行评估和比较。结果积水肾脏术前肾实质与术后综合评价无显著性差异(P>0.05),肾盂和集合系统排泄对比剂明显减慢,各ROI和SI以及持续时间与术后肾脏相比均有明显的差异(P<0.05)。结论动态增强MRI作为一种简单、安全无创的技术、联合评估肾形态和功能,对于评价肾积水手术疗效具有重要的临床价值。  相似文献   
45.
Genetically engineered mice are increasingly important in stroke research. The strains on which these constructs are built are known to have inherent differential sensitivities to ischemic insults. This has been largely attributed to differences in vascular anatomy. This study compared the outcome from forebrain ischemia in two common murine background strains using two different types of ischemic insult. C57Bl/6 and SV129 mice were subjected to two vessel (bilateral carotid) occlusion (2VO) or 2VO plus systemic hypotension (2VO+Hypo; mean arterial pressure=30+/-2 mmHg) for 10-20 min. Ventilation and pericranial temperature were controlled. Cerebral blood flow (CBF) was determined by 14C-iodoantipyrine autoradiography. Histologic damage in forebrain structures was measured 3 days post-ischemia. During 2VO+Hypo, the EEG became isoelectric in all animals. During 2VO alone, EEG isoelectricity occurred in 73% of C57Bl/6 and 50% of SV129 mice. Forebrain CBF was reduced to a similar extent in both strains. Greater CBF variability was seen with 2VO alone versus 2VO+Hypo. CBF was less in the 2VO+Hypo model. SV129 mice had wider posterior communicating but smaller basilar artery diameters. With or without hypotension, SV129 mice had markedly less severe histologic damage than C57Bl/6 mice. A time-dependent increase in histologic damage was demonstrated in the 2VO+Hypo model but not with 2VO alone. The 2VO and 2VO+Hypo models produced similar magnitudes of histologic injury in C57Bl/6 mice subjected to 10-min ischemia. SV129 mice were resistant to ischemia in either model. The 2VO+Hypo model produced a more uniform severity of ischemia as defined by CBF and EEG examination. Despite this, the murine strain had a substantially greater impact on histologic outcome than did cerebrovascular anatomy or the type of model used to produce the ischemic insult.  相似文献   
46.
Birthdates of the neurons that comprise the layers of the mature visual cortex in the wallaby (Macropus eugenii) have been determined with the aid of tritiated thymidine autoradiography. The laminar positions of cells, identified by their birthdates, have then been followed at early stages during development and compared with previously published data on the distribution of thalamocortical afferents and corticothalamic projecting cells (Sheng et al. [1991] J. Comp. Neurol. 307:17-38). Neurons are born in a deep to superficial sequence typical of other mammals. The loosely packed zone of cells, which develops at the base of the thin compact zone of cells at the superficial margin of the cortical plate early in development, was identified as being part of the cortical plate. Afferents did not wait below this zone but grew into the developing cortical layers immediately after the cells that form these layers began accumulating in the loosely packed zone, starting with layer 6 on postnatal day 22 (P22). The genesis of layer 4 did not begin until P32, and these cells reached the superficial cortical plate at P54 and entered the loosely packed zone by P65. Cells of layers 5 and 6 formed the initial projection to the thalamus. Despite the protracted development of the wallaby and the large discrepancy between the time of thalamic ingrowth and genesis of layer 4, there was no extended waiting period for afferents in the subplate.  相似文献   
47.
[目的 ] 分析上海市人类免疫缺陷病毒 (HIV )阳性人群HIV -1分布特征 ,为制定预防HIV传播措施提供科学依据。  [方法 ] 选择 40例不同感染途径的HIV阳性者 ,提取其血浆中核酸进行扩增 ,然后进行序列测定 ,确定其HIV -1型别。  [结果 ]  3 8例分离到核酸的阳性者中 ,发现 4种HIV -1亚型 (A、B、B’和C)、2种重组亚型 (CRF0 1_AE和CRF0 8_BC)和 1种未见报道的亚型 (CRF0 1_AEenvBgagUpol)。不同人群感染毒株不同 ,经性接触传播感染者感染毒株较为广泛 ( 7种 ) ,而经血传播者都为B/B’亚型。  [结论 ] 上海地区存在着多样的HIV -1亚型和重组毒株  相似文献   
48.
MR图像伪影的识别与消除   总被引:3,自引:0,他引:3  
目的 探讨MR图像伪影形成的原因、表现形式及消除方法。方法 对100份有伪影干扰的MR图像进行回颐性分析、总结。结果 MR图像伪影产生的来源主要有4个方面:磁场,包括梯度场的不均匀性;外界射频干扰;采集技术的不恰当;运动和流动效应。结论 正确识别各种伪影的图像特征,对提高MR诊断准确率有着重要意义。  相似文献   
49.
目的探讨临床上对非淋菌性尿道(宫颈)炎合并盆腔感染有效的治疗方法。方法将妇产科及性病科门诊确诊的非淋菌性尿道(宫颈)炎合并盆腔感染201例病人随机分为2组,治疗组采用头孢曲松纳加阿奇霉素治疗,对照组采用头孢曲松纳加口服美满霉素治疗。结果治疗组治愈率为80.95%,总有效率为97.14%;对照组治愈率为58.33%,总有效率为69.79%。两者的,临床治愈率及有效率有显著性的差异(P<0.005)。结论头孢曲松纳加阿奇霉素静脉给药治疗非淋菌性尿道(宫颈)炎合并盆腔感染取得良好的治疗效果,较头孢曲松纳加美满霉素效果有显著性提高。  相似文献   
50.
目的了解城乡蒙汉族中小学女生的经前准备情况,为开展青春期健康教育提供科学依据.方法采用分层整群抽样的方法,对蒙汉族中小学女生6 298名进行经前准备情况调查.结果城乡蒙汉族中小学女生的经前教育情况城市好于农村,汉族好于蒙族,但总体情况不容乐观.对月经感到紧张忧虑的女生其月经失调、痛经和经前期紧张综合征的发生率均较高.结论应对中小学女生进行正确的、恰当的经前教育,以确保其身心健康.  相似文献   
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