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31.
目的探讨LDL/HDL比值与绝经后女性2型糖尿病患者骨强度以及骨折风险的相关性。方法选取2014年1月至2018年1月在我院内分泌科就诊的女性2型糖尿病(type 2 diabetes mellitus,T2DM)患者226例,其中113例已绝经,将患者分为未绝经组与已绝经组。运用超声骨密度仪(QUS)分别测量受试者的骨强度指数(stiffness index,SI),同时收集患者一般资料如年龄、体质量指数(bone mass index,BMI)、糖尿病病程等,测定血脂、糖化血红蛋白、骨钙素(BGP)、血清Ⅰ型原胶原N-端前肽(PINP)、血清1型胶原交联β-C-末端肽(β-CTX),并计算TC/HDL比值(THR)、LDL/HDL比值(LHR)。采用骨折风险预测工具模型(FRAX)计算患者10年任何重要部位骨质疏松性骨折(PMOF)、髋部骨折(PHF)概率。采用线性回归分析不同血脂指标与SI相关性,进一步评估LHR与骨代谢、PMOF和PHF等的相关关系。结果 (1)与未绝经组相比,已绝经组SI[(79. 96±11. 35) VS (92. 50±15. 95),P0. 001)]、BGP[(13. 47±4. 11) VS (21. 00±10. 90),P=0. 039)]、PINP [(34. 59±16. 16) VS (56. 70±37. 33),P=0. 016]降低,β-CTX[(590. 71±263. 24) VS (423. 07±198. 04),P=0. 021]、LHR[(2. 16±0. 76)VS (1. 89±0. 81),P=0. 040)]、PMOF[(3. 67±1. 28) VS (1. 50±0. 14),P=0. 009]、PHF[(1. 44±0. 61) VS (0. 65±0. 12),P=0. 005]升高,差异有统计学意义;(2) Pearson相关性分析结果提示SI与PMOF、PHF呈负相关(β=-0. 749;β=-0. 681,P均0. 001);(3)分别校正年龄与BMI(β=-0. 245,P=0. 006),Hba1c与病程(β=-0. 240,P=0. 009),年龄、BMI、Hba1c、病程和肌酐(β=-0. 248,P=0. 005),绝经后2型糖尿病患者LHR与SI均有显著负相关;(4) LHR与PMOF、PHF、β-CTX呈正相关(β=0. 336;β=0. 319;β=277,P均0. 05),与BGP、PINP呈负相关(β=-0. 310;β=-0. 298,P均0. 05)。结论绝经后2型糖尿病患者LHR与SI、FRAX骨折风险评分以及骨代谢指标相关,高LHR可能引起SI下降、骨折风险增高,其机制可能与成骨减少、破骨增加有关。  相似文献   
32.
目的探讨阿魏酸钠(Sodium ferulate,SF)对HepG2细胞低密度脂蛋白受体(low density lipoproteinreceptor,LDLR)mRNA表达的影响。方法培养HepG2细胞,不同浓度阿魏酸钠干预后,通过RT-PCR技术,半定量检测LDLR mRNA的表达。结果阿魏酸钠100μg/ml可上调HepG2细胞LDLR mRNA表达26%,200μg/ml可上调46%。结论阿魏酸钠具有上调LDLR mRNA表达的作用,且呈量效依赖关系。  相似文献   
33.
救心胶囊对LDL损伤内皮细胞血管舒缩因子释放的影响   总被引:3,自引:0,他引:3  
目的 :通过观察救心胶囊对损伤内皮细胞血管舒缩因子释放的影响 ,探讨该药防治冠心病的作用机制。方法 :建立LDL损伤内皮细胞模型 ,用两种不同的给药方式———无菌中药提取液和载药血清处理以上模型 ,分别运用放免和生化的方法检测ET 1、TXB2 、PGFlα、和NO的表达。结果 :内皮细胞损伤后舒张因子水平降低而收缩因子表达明显增加 ,救心胶囊可以调节血管舒缩因子的失衡状态。结论 :救心胶囊通过保护内皮细胞 ,维持血管的正常舒缩状态 ,从而延缓冠心病的发生发展  相似文献   
34.
目的:构建ox-LDL特异性人血管平滑肌细胞cDNA消减文库。方法:35%ug/ml ox-LDL刺激培养的人血管平滑肌细胞,利用消减杂交技术,构建cDNA消减文库,并运用蓝白斑筛选和影印杂交进一步确定文库克隆的特异性。结果:成功构建ox-LDL特异性血管平滑肌细胞cDNA消减文库,约2000个白色克隆。影印杂交后共获82个差异表达克隆。结论:消减文库的构建为进一步克隆ox-LDL特异性基因cDNA片段和全长奠定了基础。  相似文献   
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37.
杨荣国 《中外医疗》2015,(3):100-101
目的:探讨不同剂量瑞舒伐他汀钙(10 mg和20 mg)对急性冠脉综姓合征(ACS)非PCI药物保守治疗患者血清铁蛋白、血脂水平及炎性因子的影响。方法将2010年1月—2014年6月该院收治的ACS非PCI药物保守治疗患者120例随机分为A、B、C 3组各40例,在给予吸氧、抗凝、扩张冠脉血管等治疗的基础上,A组口服瑞舒伐他汀钙10 mg,B组口服瑞舒伐他汀钙20 mg,C组口服阿托伐他汀钙20 mg,均1次/d。治疗前和治疗16周后抽取静脉血,观察3组治疗前后血清LDL、oxLDL、hsCRP水平。结果 A组治疗后血清铁蛋白、LDL、oxLDL、hsCRP分别为(189.27±11.15) ng/mL、(3.08±0.17) mmol/L、(45.17±1.63) mmol/L、(5.48±0.22) mmol/L;B组治疗后血清铁蛋白、LDL、oxLDL、hsCRP分别为(89.24±12.16) ng/mL、(2.51±0.31) mmol/L、(40.78±0.69) mmol/L、(4.34±0.27) mmol/L;C组治疗后血清铁蛋白、LDL、oxLDL、hsCRP分别为(195.78±13.65)ng/mL、(3.11±0.21) mmol/L、(45.24±1.71) mmol/L、(5.49±0.27) mmol/L。三组患者治疗16周后血清铁蛋白、血清LDL、oxLDL、hsCRP水平均较治疗前明显降低(P<0.05)。其中B组较A、C组降低明显(P<0.05),A组与C组比较有差异,但差异无统计学意义(P>0.05)。结论 ACS非PCI药物保守治疗患者早期使用不同剂量瑞舒伐他汀钙能明显降低血清LDL、oxLDL、hsCRP水平,降低血脂水平,降低炎性因子,减轻炎性反应,可能起到稳定斑块、抗栓、改善预后的作用。  相似文献   
38.
Despite numerous studies, the precise role of dietary n-6 polyunsaturated fatty acids in the pathogenesis of atherosclerosis remains controversial. It has been shown that feeding an n-6-enriched diet resulted in decreased atherosclerosis in African green monkeys and was associated with a reduction in LDL levels. However, other authors reported that n-6 supplementation increased the oxidative stress and the susceptibility of LDL to undergo in vitro oxidation, thus potentially enhancing atherosclerosis. The present study was designed to investigate the effect of dietary supplementation of n-6 polyunsaturated fats (safflower oil), as compared with a saturated fat-rich diet (Paigen), on the blood lipid profile and atherosclerosis in two mouse models. In the first experiment, female C57BL/6 mice (n=23–30 per group) were fed a cholate containing Paigen diet, a safflower oil-rich diet (with cholate), or normal chow for 15 weeks. No significant differences between the high fat diet groups were evident with respect to total cholesterol, LDL, HDL or triglyceride levels. The extent of aortic sinus fatty streaks did not differ significantly between the two groups. In the second experiment, LDL-receptor-deficient (LDL-RD) mice (n=20–30 per group) were randomized into similar dietary regimens. Mice consuming a safflower oil-enriched diet developed significantly less atherosclerosis, in comparison with Paigen diet-fed mice. A reduction in LDL levels, although not of a similar magnitude as the reduction in atherosclerosis, was evident in the safflower oil-fed mice when compared to the Paigen diet-fed littermates. In both mouse models of atherosclerosis, LDL isolated from the plasma of mice on the n-6 polyunsaturated diet was rendered slightly more susceptible to oxidation in vitro, as indicated by a shorter lag period for diene formation. Thus, the effects of n-6 fatty acids on the lipoprotein composition and other potential influences may have contributed to the anti-atherogenic effect in the LDL-RD mouse model.  相似文献   
39.
A simple equation established by Cordova &; Cordova (LDL-COR) was developed to provide an improved estimation of LDL-cholesterol in a large Brazilian laboratory database. We evaluated this new equation in a general population cohort in Pomerania, north-eastern Germany (SHIP Study) compared to other existing formulas (Anandaraja, Teerakanchana, Chen, Hattori, Martin, Friedewald and Ahmadi), and its power in the prediction of death by atherosclerosis related events as the primary outcome. Analysis was conducted on a cohort of 4075 individuals considering age, gender, use of lipid lowering therapy and associated co-morbidities such as diabetes, hepatic, kidney and thyroid disease. LDL-COR values had a lower standard deviation compared to the previously published equations: 0.92 versus 1.02, 1.02, 1.03, 1.04, 1.09, 1.10 and 1.74?mmol/L, respectively. All of the factors known to affect the results obtained by the Friedewald’s equation (LDL-FW), except fibrate use, were associated with the difference between LDL-COR and LDL-FW (p?p?=?.06). LDL-COR determined a higher hazard ratio (1.23 versus 1.12, 1.19, 1.21, 1.19, 1.21 and 1.19) for cardiovascular disease related mortality, incident stroke or myocardial infarction compared to the other evaluated formulas, except for Ahmadi’s (1.24), and the same adjusted predictive power considering all confounding factors. The proposed simple equation was demonstrated to be suitable for a more precise LDL-c estimation in the studied population. Since LDL-c is a parameter frequently requested by medical laboratories in clinical routine, and will probably remain so, precise methods for its estimation are needed when direct measurement is not available.  相似文献   
40.
AimsTo systematically evaluate the evidence regarding the effects of foods on LDL cholesterol levels and to compare the findings with current guidelines.Data synthesisFrom inception through June 2019, we searched PubMed, Cochrane Database of Systematic Reviews, and Cochrane Central Register of Controlled Trials for guidelines, systematic reviews, and RCTs (for coffee intake only) of at least 13 days duration. Additionally, we searched Trip database for guidelines from 2009 through Oct 2019. Language was restricted to English. The strength of evidence was evaluated using The Grading of Recommendations Assessment, Development, and Evaluation (GRADE). A total of 37 guidelines, 108 systematic reviews, and 20 RCTs were included. With high evidence, foods high in unsaturated and low in saturated and trans fatty acids (e.g. rapeseed/canola oil), with added plant sterols/stanols, and high in soluble fiber (e.g. oats, barley, and psyllium) caused at least moderate (i.e. 0.20–0.40 mmol/L) reductions in LDL cholesterol. Unfiltered coffee caused a moderate to large increase. Soy protein, tomatoes, flaxseeds, and almonds caused small reductions. With moderate evidence, avocados and turmeric caused moderate to large reductions. Pulses, hazelnuts, walnuts, high-fiber/wholegrain foods, and green tea caused small to moderate reductions, whereas sugar caused a small increase. Other identified foods were either neutral or had low or very low evidence regarding their effects.ConclusionsSeveral foods distinctly modify LDL cholesterol levels. The results may aid future guidelines and dietary advice for hypercholesterolemia.  相似文献   
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