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101.
持续压力超负荷对兔左心室细胞凋亡的影响 总被引:3,自引:1,他引:2
OBJECTIVE: To study the effect of chronic pressure overload on the apoptosis of the left ventricle myocytes in rabbits. METHODS: Rabbit models of chronic pressure overload-induced heart failure were prepared in which dynamic changes of apoptotic myocytes in the left ventricle were observed by way of terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay. RESULTS: Only a few apoptotic cells was observed in the sham-operated group, while in the experimental group, the apoptotic left ventricle myocytes significantly increased after operation, presenting a peak level between day 3 and day 7. Seven days after the operation, the apoptotic myocytes began to decrease and till day 14, the apoptotic cell number had been smaller than that measured on day 1. When signs of heart failure set in, the apoptotic myocytes were again increased (P<0.001). CONCLUSION: During chronic pressure overload, myocyte apoptosis in the left ventricle is elevated at the early stages and undulates subsequently, with the peak occurring before hypertrophy is obvious. 相似文献
102.
高效液相色谱法测定右旋儿茶素血浆浓度及药代动力学参数 总被引:1,自引:0,他引:1
本文建立了体液中右旋儿茶素的RP-HPLC测定方法。采用C_(18)键合相硅胶为填料的固相提取柱进行样品预处理,右旋儿茶素的提取回收率为79.8%.应用二极管阵列检测器对色谱峰纯度进行鉴定。该法精密度好,方法回收率近100%,日内、日间的变异系数为2.4~5.6%,血浓69.6~1160 ng/ml范围内呈线性关系,r=0.9993。家兔静注右旋儿茶素18mg/kg,其药代动力学过程符合二室模型,分布相半衰期为0.129 h,消除相半衰期为1.19h。 相似文献
103.
DICOM通讯程序的设计 总被引:3,自引:0,他引:3
本文在研究DICOM协议的基础上,介绍了DICOM通讯的消息结构;从设计出发,分析了DICOM通讯过程的各个技术环节。 相似文献
104.
单次静注爱肌松(0.3mg·kg-1,对照组)于3.17±0.81分钟(x±s)可获得满意的气管插管条件。预注组(10例)首次量0.27mg·kg-1于预注剂量(0.03mg·kg-1)后5分钟给予,可使爱肌松的起效时间缩短至0.93±0.17分钟(P<0.001),TOF无反应期、25%和90%恢复时间两组无显著差别(P>0.25)。全部病例均获得了良好的气管插管条件,预注的优点还在于能评估患者对所选用非去极化肌松药的敏感性。预往后TOF肌电图T1抑制>10%较无明显TOF抑制者肌松恢复时间显著延长(P<0.05)。同时发现吸入安氟醚可使爱肌松作用时效延长。 相似文献
105.
钙和鸡冠花黄酮提取物对大鼠废用性骨质疏松的作用 总被引:4,自引:0,他引:4
目的探讨钙和鸡冠花黄酮提取物对废用性骨质疏松大鼠的作用,为骨质疏松的防治提供依据.方法选用健康SD大鼠40只,雄性.随机分为5组,第1、2组分别为正常对照和阳性对照,灌胃蒸馏水5 ml/(kg@d),第2~5组制造废用性骨质疏松大鼠模型,第3、4、5组为预防组,分别灌胃等量鸡冠花提取物,碳酸钙,鸡冠花提取物加钙溶液.实验8周后,测骨密度(BMD),股骨CT值,测血清MDA、SOD及24 h尿钙、羟脯氨酸(HOP)、尿肌酐含量等.结果阳性组与正常对照组比较股骨重、灰分重、CT值、血清钙下降,尿钙、尿HOP升高(P<0.05或0.01),预防组与阳性组比较股骨重、CT值显著增加,碳酸钙组、鸡冠花加钙组灰分重显著增加(P<0.05).与阳性组比较各预防组血清钙增加,尿钙、尿HOP减少(P<0.05或<0.01).鸡冠花组、鸡冠花加钙组与阳性组比较股骨BMD、血清SOD升高,MDA降低,单纯补钙组仅BMD升高(P<0.05或<0.01).结论鸡冠花提取物、钙对废用性骨质疏松大鼠骨质代谢均有促进作用,两者合用具有更好的预防效果,能延缓或减轻废用性骨质疏松的发生. 相似文献
106.
四种可溶性载体对骨形态发生蛋白在小鼠体内诱导成骨活性的影响 总被引:28,自引:0,他引:28
以四种可溶性物质作为牛骨形态发生蛋白(bBMP)的载体,通过实验观察哪种物质是bBMP的有效缓释载体。将聚乙烯吡咯烷酮(PVP)、葡聚糖、羟乙基淀粉(HES)、甘露醇分别与等量bBMP复合后,注射入小鼠股部肌肉,观察组织学成骨及测定标本内钙含量。结果,bBMP/PVP有良好成骨,吸收较快,未见炎症及排斥反应,其混悬液较稳定,具有良好的适针性及可注射性,bBMP/甘露醇只有很低成骨率。其余各组未见成骨。PVP对bBMP具有满意助溶、助悬及缓释载体作用,对bBMP活性无损害,生物相容性好。 相似文献
107.
建立了较完整的估计重油和沥青中饱和碳浓度数方法,其中包括环烷桥头碳、环烷甲基取代碳、环烷烷基(≥C2)取代碳等。基于理论分析,建立了估计环间的桥链和各种平均结构参数的方法,包括平均芳环环核数和环烷环环核数、芳环和环烷环烷工取代度、单元片上芳环和环烷环数。从实验数据出发,提出了烷基链长分布的公式。 相似文献
108.
African Americans experienced massive internal migrations that shifted more than 6 million Southern-born blacks to other sections of the United States over the past century, a trend that only recently has been reversed. Whenever mass migration takes place, there is an opportunity to examine the role of the native and relocated environments in the development of disease. This article examines those relationships for diabetes mellitus, a group of diseases that disproportionately affect African-Americans relative to other racial and ethnic groups in the United States. Age-specific and age-adjusted rates with 95% confidence intervals were calculated for males and females for combinations of five regions of birth and four regions of residence at time of death. Southern-born males had statistically significantly higher death rates from diabetes than did their counterparts who died in the same regions in 9 of 16 comparisons. For females, those born in the South had statistically significantly higher rates in 15 of 16 comparisons. The results of this study indicate that place of birth and early life experiences are statistically associated with diabetes mortality among African Americans regardless of place of residence at time of death. 相似文献
109.
110.
Resection was carried out in 1,025 of 1,654 patients with cancer of the esophagus or esophagogastric junction at the Peking Medical College Hospitals in China from 1953 through 1973. All cancers of the esophagus were squamous cell carcinomas except for five adenocarcinomas. A lesion localized within the esophageal wall was found in 55% and lymph node metastasis in 41.3% of the patients undergoing resection. All cancers of the esophagogastric junction were adenocarcinomas. The tumor had invaded beyond the boundaries of the stomach in 76.7% of these patients, and positive nodes were found in 61% of the patients. The rate of resectability was 81.2% for esophageal cancer and 74% for cancer of the esophagogastric junction. Surgical mortality after resection was 4.9% (50/1,025). The 5-year survival after resection was 20.9% (214/1,025). Better results were found following complete resection: 24% (210/875) for all patients, 28.2% (162/575) for patients with cancer of the esophagus, and 16% (48/300) for patients with cancer of the esophagogastric junction. Late survival at 10, 15, and 20 years after resection of esophageal cancer was 20%, 12%, and 7.4%, respectively. The favorable prognostic factors after resection of esophageal cancer were tumor of the lower third of the esophagus, the absence of lymph node involvement, and the presence of a localized lesion. The 5-year survival for patients with cancer of the lower third of the esophagus was 32.7%. It was 64.2% for patients with a localized lesion with negative nodes in this subgroup. 相似文献