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131.
背景及目的:随机对照临床试验已经表明阿司匹林可降低结直肠癌的发生风险,动物实验还发现其可抑制肿瘤生长与转移,但阿司匹林与已确诊结直肠癌患者存活率的关系仍不可知.本研究探讨了在已确诊的结直肠癌患者中,阿司匹林与结直肠癌总体存活率的关系.  相似文献   
132.
背景及目的:随机对照临床试验已经表明阿司匹林可降低结直肠癌的发生风险,动物实验还发现其可抑制肿瘤生长与转移,但阿司匹林与已确诊结直肠癌患者存活率的关系仍不可知.本研究探讨了在已确诊的结直肠癌患者中,阿司匹林与结直肠癌总体存活率的关系.  相似文献   
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134.
The purpose of the study was to determine if there is a relationship between types of entry-level preparatory nursing programmes in which a nurse receives basic nursing education and conceptual and theoretical approaches to patient care. A secondary purpose of the study was to determine if there is a relationship between entry-level basic preparatory nursing education and nursing leadership, the ability to make nursing diagnosis, and implementation, as well as evaluation of the nursing process. Three nursing practice categories were identified and included: professional, all-nurse and technical. Useable data collected by short-essay questionnaire from 343 out of 344 sample subjects were computed to determine the relationship, if any, between basic preparatory nursing education and conceptual and theoretical approaches to patient care. Decisions about three null hypotheses were made at the 0.05 level of significance utilizing analysis of covariance and the 0.01 level of significance utilizing chi-square analysis. For Hypothesis 1, the main effect for degree work when covaried with Verbal Scholastic Aptitude Test scores, Quantitative Scholastic Aptitude Test scores, time and age indicated a significance of 0.001 for all item associations in the professional, all-nurse and technical categories utilizing analysis of covariance, and 0.001 utilizing chi-square analysis. For Hypotheses 2 and 3, the main effect for degree work when covaried with the aforementioned variables indicated a significance of 0.001 utilizing analysis of covariance, and 0.001 utilizing chi-square analysis. In conclusion, the findings from the study suggest that graduates of baccalaureate degree programmes do vary in conceptual and theoretical approach to nursing care in specific nursing care situations.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
135.
In 22 hemodialysis patients, during a dialysis session, the solute removal index (SRI) for urea obtained from the use of a partial spent dialysate collection method was compared with that derived from the use of a total spent dialysate collection technique. The partial spent dialysate collection method was used to harvest a small representative sample of the total spent dialysate. The volumes of spent dialysate collected by the partial and the total spent dialysate collection methods were 1.7 +/- 0.4 L and 129.6 +/- 15.3 L, respectively. The total amount of urea nitrogen removed by dialysis as estimated by the partial spent dialysate collection method was similar to that determined by the total spent dialysate collection approach. As a result, the SRI value for urea obtained by the partial spent dialysate collection method (namely, 63% +/- 8%) correlated very well (r = 0.95, P < 0.001) with that derived by the total spent dialysate collection technique (namely, 62% +/- 8%). Our data suggest that it is feasible to use a simple partial spent dialysate collection method to obtain SRI results in patients treated with hemodialysis.  相似文献   
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137.
Glioblastoma multiforme (GBM) is the most common type of primary malignant brain tumor. Although comprehensive therapeutic measures are available, recurrence is very frequent and the prognosis of GBM remains dismal. To date, little is known about the molecular pathogenesis associated with GBM recurrence. According to Knudson ' s two-hit hypothesis of tumor suppressor gene (TSG) inactivation,1 deletion of a chromosomal region, as revealed by loss of heterozygosity (LOH), is often indicative of the presence of a potential TSG. Allelotype studies involving a comprehensive LOH analysis of the whole genome can provide more detailed and thorough information for detecting genetic anomalies than traditional LOH analysis. The present study is designed to conduct a genome-wide allelotype analysis of one patient ' s primary and corresponding recurrent GBM tumors in an effort to reveal molecular genetic alterations associated with the recurrence of this malignancy.  相似文献   
138.
139.
d-生物素的立体专一性全合成研究   总被引:1,自引:0,他引:1  
对confaione的d-生物素(1)全合成进行了改进,从半胱氨酸计算,总收率3.7%。5与4-溴代三苯膦丁酸甲酯进行Wittig-Schlosser缩合反应可立体专一性地转化成反式-烯(6)。以叠氮三甲基硅烷代替叠氮化锂亲核进攻9分子中C3-溴原子,可显著地提高顺式-叠氮内酰胺10的收率。  相似文献   
140.
In the present study we have investigated the effect of CD45, CD45RA and CD45RO monoclonal antibodies (MoAbs) on the CD3 receptor-mediated proliferation of human T lymphocytes. It is shown that CD3-induced proliferation of purified resting T cells and quiescent T lymphoblasts (QTL) is promoted via all of the investigated CD45-associated epitopes. It is also shown that the CD45 molecules are required to be cross-linked for costimulation. The MoAbs enhance the interleukin-2 (IL-2) production of CD3-stimulated QTL. The elevation of the IL-2 production correlates with the increase in CD3-induced cell proliferation suggesting that the CD45-driven regulation of T lymphocyte activation is linked to the IL-2 pathway.  相似文献   
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