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391.
26万女性队列人群中乳腺癌与人工流产关系的研究(上海) 总被引:2,自引:0,他引:2
目的:评估人工流产(指手术流产)对乳腺癌危险性的可能影响.方法:研究在上海267 040例妇女的一项乳房自我检查随机试验的队列人群中进行,由队列研究和巢式病例对照研究两部分组成.结果:依据基线调查表采集的资料分析,人工流产不增加乳腺癌危险性.调整潜在的混淆因素后,OR=1.06(95%CI:0.91~1.25).人工流产次数增加无危险性趋势增加.从更详细的652例乳腺癌病例和694例对照资料分析,得出相似的结果.人工流产发生在首次生育后不增加危险性;少数妇女在首次生育前人工流产以及妊娠13周后人工流产,虽然被观察到危险性有增加,但无显著性统计学意义.结论:在中国,人工流产不是乳腺癌发生的重要原因. 相似文献
392.
White cell-poor blood components are useful in patients with white cell antibodies. White cells are efficiently removed by two different filters, Imugard and Erypur, which have used saline as the filter solution. This study evaluated these filters as to their production of white cell-poor platelets. Pools of random-donor platelet concentrates were filtered. Prefiltration and postfiltration samples were evaluated for percentages of platelet recovery, white cell (WBC) removal, and platelet function. The two filter solutions tested were normal-strength saline (NSS) and fresh-frozen plasma (FFP). Postfiltration samples using NSS showed no measurable platelet aggregation with ADP, epinephrine, or collagen. However, with FFP, both filters showed 100 percent platelet aggregation with ADP, epinephrine, and collagen. The FFP filter solution provided excellent white cell removal in both filters (Imugard: 100% WBC removal or less than 1.0 X 10(6) residual WBC; Erypur: 99.5% removal or greater than 1.0 X 10(7) residual WBC); however, platelet recovery was better with Imugard (95%) than with Erypur (55%). The filtration procedure is an excellent method for the preparation of white cell-poor platelets; however, the quantity of the saline solution recommended for the filtering of red cells must be minimized for platelets. 相似文献
393.
Rui V. Sim?es Inna S. Serganova Natalia Kruchevsky Avigdor Leftin Alexander A. Shestov Howard T. Thaler George Sukenick Jason W. Locasale Ronald G. Blasberg Jason A. Koutcher Ellen Ackerstaff 《Neoplasia (New York, N.Y.)》2015,17(8):671-684
Cancer cells adapt their metabolism during tumorigenesis. We studied two isogenic breast cancer cells lines (highly metastatic 4T1; nonmetastatic 67NR) to identify differences in their glucose and glutamine metabolism in response to metabolic and environmental stress. Dynamic magnetic resonance spectroscopy of 13C-isotopomers showed that 4T1 cells have higher glycolytic and tricarboxylic acid (TCA) cycle flux than 67NR cells and readily switch between glycolysis and oxidative phosphorylation (OXPHOS) in response to different extracellular environments. OXPHOS activity increased with metastatic potential in isogenic cell lines derived from the same primary breast cancer: 4T1 > 4T07 and 168FARN (local micrometastasis only) > 67NR. We observed a restricted TCA cycle flux at the succinate dehydrogenase step in 67NR cells (but not in 4T1 cells), leading to succinate accumulation and hindering OXPHOS. In the four isogenic cell lines, environmental stresses modulated succinate dehydrogenase subunit A expression according to metastatic potential. Moreover, glucose-derived lactate production was more glutamine dependent in cell lines with higher metastatic potential. These studies show clear differences in TCA cycle metabolism between 4T1 and 67NR breast cancer cells. They indicate that metastases-forming 4T1 cells are more adept at adjusting their metabolism in response to environmental stress than isogenic, nonmetastatic 67NR cells. We suggest that the metabolic plasticity and adaptability are more important to the metastatic breast cancer phenotype than rapid cell proliferation alone, which could 1) provide a new biomarker for early detection of this phenotype, possibly at the time of diagnosis, and 2) lead to new treatment strategies of metastatic breast cancer by targeting mitochondrial metabolism. 相似文献
394.
Basic fibroblast growth factor expression in human bone marrow and peripheral blood cells 总被引:9,自引:2,他引:9
We have shown previously that basic fibroblast growth factor (bFGF) is a mitogen for human bone marrow (BM) stromal cells and that bFGF stimulates myelopoiesis in primary BM cultures. In this article, we demonstrate the presence of bFGF in two cell lineages in human BM and peripheral blood as well as the deposition of bFGF into the extracellular matrix of BM stromal cell cultures. In immunofluorescence experiments on BM and peripheral blood smears, megakaryocytes and platelets stained strongly for bFGF, whereas weaker staining was observed in immature and mature cells of the granulocyte series. The presence of bFGF in platelets was confirmed by enzyme-linked immunosorbent assay as well as by immunoprecipitation followed by immunoblotting. bFGF was synthesized by BM stromal cell cultures and was found either cell associated or localized in the nucleus and the nucleoli, and its location was dependent on the fixation procedure used. Addition of exogenous bFGF to stromal cells showed the presence of extracellular binding molecules for this cytokine. bFGF could be released from these sites by soluble heparin or phosphatidylinositol- specific phospholipase C. This study supports the role of bFGF as a stromal cell mitogen and stimulator of myelopoiesis. The data indicate that the stromal cells produce bFGF and that their extracellular matrix can serve as a reservoir for this growth factor. In addition, the results suggest a possible involvement of bFGF in platelet function as well as in megakaryocytopoiesis. 相似文献
395.
Oestmann JW; Kopans DB; Linetsky L; Hall DA; McCarthy KA; White G; Swann C; Kelley JE; Johnson LL 《Radiology》1988,168(3):657-659
A new dual-screen, dual-emulsion-film combination that allows a decrease in radiation dose of approximately 66% was compared with a widely used single-screen, single-emulsion-film system in contact and magnification mammography. Clustered microcalcifications randomly superimposed on a breast phantom were detected, and the location and number of individual calcifications were determined by four observers. The detectability of calcifications, determined with a receiver operating characteristic (ROC) analysis area, was 0.92 for magnification and 0.82 for contact mammography with the single-emulsion-film system, compared with 0.84 and 0.72, respectively, with the dual-emulsion-film system. More clusters were correctly located and more individual calcifications were counted with magnification than with contact mammography. The dual-emulsion-film system with the magnification technique performs as well as the single-emulsion-film system with the contact technique, while retaining a decrease in required dose of approximately 40%. 相似文献
396.
高效液相色谱法对四种双氯灭痛软膏剂透皮效果的研究 总被引:2,自引:0,他引:2
目的:本实验采用高效液相色谱法,以离体小白鼠腹部皮肤为透皮屏障,比较了四种双氯灭痛软膏剂的透皮效果,方法:实验用法国Gilson公司的HPLC仪,以C18为固定相,甲醇-水(含HAc 0.36%)=80:20为流动相,紫外检测波长280nm。平均回收率为99.59%,RSD<3.28%,检测限为1.0ug/ml。结果:1号样品透皮率最高,3号与1号相比较透皮吸收无显著性差异(P>0.05),2号或4号分别与1号相比,其透皮吸收均有显著性差异(P<0.05),结论:1号品值得进一步开发。 相似文献