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991.
From April 2000 to November 2002, the Department of Health (England) placed 681 automated external defibrillators (AEDs) in 110 public places for use by volunteer lay first responders. An audit has been undertaken of the first 250 deployments, of which 182 were for confirmed cardiac arrest. Of these, 177 were witnessed whilst 5 occurred in situations that were remote or initially inaccessible to the responders. The response interval between collapse and the initiation of CPR or AED placement was estimated to be 3-5 min in most cases. Ventricular fibrillation or rapid ventricular tachycardia (one case) was the first recorded rhythm in 146 cases (82%). In all, 44 of the 177 witnessed cases are known to have survived to hospital discharge (25%). Complete downloads are available for 173 witnessed cases and of these 140 were shocked: first-shock success, defined as termination of the fibrillatory waveform for 5 s or more, was achieved in 132 of them. When data quality permitted, the downloads were analysed with special reference to the numbers of compressions given and also to interruptions in compression sequences for ventilations, for rhythm analysis by the AED, for clinical checks, and for unexplained operator delays. The average rate of compressions during sequences was 120 min(-1), but because of interruptions, the actual number administered over a full minute from the first CPR prompt was a median of only 38. The speed of response by the lay first responders in relation to AED use was similar to that reported for healthcare professionals.  相似文献   
992.
993.
Cytotoxicity of three cycloartane triterpenoids from Cimicifuga dahurica   总被引:3,自引:0,他引:3  
Tian Z  Yang M  Huang F  Li K  Si J  Shi L  Chen S  Xiao P 《Cancer letters》2005,226(1):65-75
We first investigated the cytotoxicity of three cycloartane triterpenoids isolated from the aerial part of C. dahurica. Their cytotoxic activity was investigated on several cancer cell lines including solid tumor (HepG2), blood tumor (HL-60), drug resistant tumor (R-HepG2) and primary cultured normal mouse and rat hepatocytes in order to find efficient anti-tumor agents against both parental and drug-resistant tumor with reduced toxicity. Evident cytotoxicity of these compounds on all tested neoplastic cell lines revealed that they are efficient on both drug-resistant tumor and parental tumor. Furthermore, they all showed relatively selective cytotoxicity on cancerous cells based on the higher IC(50) values of them on normal cells than that on tumor cells. Morphological observation and cell cycle analysis were employed to elucidate the cytotoxicity of the tested compounds. They brought out similar apoptotic morphological changes and G(2)/M cell cycle arrest in HepG2, R-HepG2 and HL-60 cells. Moreover, they suppressed the expression of cdc2 and COX-2 protein. These results imply that the three compounds possess potential anti-tumor activities and they exert their cytotoxicity via apoptosis and G(2)/M arrest. In addition, inhibition of cdc2 protein expression correlates with mechanism of G(2)/M arrest.  相似文献   
994.
Detection of Toxoplasma gondii infection with sensitive and specific methods is a key step in the prevention and treatment of toxoplasmosis. Among the available diagnostic tests, serology is commonly used. Although serological tests give satisfactory results, the production of reliable reagents remains laborious and expensive. There is therefore a real need to acquire specific and effective recombinant antigens for the serodiagnosis of T. gondii infection. In this study, a multiepitope peptide was designed and successfully expressed in Escherichia coli, and then IgG and IgM enzyme-linked immunosorbent assays (ELISAs) were developed and evaluated. Our results showed that the new multiepitope antigen is one of the most promising recombinant antigens which could be used in routine screening of human toxoplasmosis.  相似文献   
995.
背景:作者既往研究发现海藻酸多糖衍生物有促进骨细胞生长的作用.目的:探索海藻酸多糖衍生物治疗骨质疏松的效果.方法:60 只Wistar 雌性大鼠随机分成对照组,治疗组和模型组,每组20 只.治疗组和模型组大鼠用维甲酸诱导产生骨质疏松模型.治疗组大鼠每只每公斤每天10 mg 多糖衍生物灌胃,模型组每只每公斤每天10 mg 葡萄糖灌胃,持续2 周.观察大鼠股骨病理形态学和骨组织形态计量学变化.结果与结论:与对照组相比,模型组大鼠股骨骨小梁面积、平均骨小梁厚度、骨小梁密度显著降低,而髓腔质间隔宽度则明显增加;经过海藻多糖衍生物治疗后,治疗组大鼠股骨平均骨小梁密度,平均骨小梁厚度和骨小梁面积较模型组均显著上升,同时髓腔质间隔宽度明显下降;说明海藻酸性多糖能有效促进骨细胞生长,可治疗和预防骨质疏松.  相似文献   
996.
997.
AIM:To investigate the anti-tumor effects of Paris chinensis dioscin(PCD)and mechanisms regarding cell cycle regulation and apoptosis in human gastric cancer SGC-7901 cells.METHODS:Cell viability was analyzed by the 3-(4,5-di-methylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay.Cell apoptosis was evaluated by flow cytometry and laser scanning confocal microscope(LSCM)using Annexin-V/propidium iodide(PI)staining,and the cell cycle was evaluated using PI staining with flow cytom-etry.Intracellular calci...  相似文献   
998.

Background  

Recently, endoscopic submucosal dissection has been carefully applied in early gastric cancer (EGC) with undifferentiated type. However, there are no individual guidelines for endoscopic treatment of EGCs with poorly differentiated tubular adenocarcinoma or signet ring cell carcinoma. The aim of this study was to investigate and compare the clinicopathologic features of these two types of EGC to guide the application of endoscopic treatment.  相似文献   
999.
1000.
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