全文获取类型
收费全文 | 15564篇 |
免费 | 1390篇 |
国内免费 | 1070篇 |
专业分类
耳鼻咽喉 | 118篇 |
儿科学 | 221篇 |
妇产科学 | 142篇 |
基础医学 | 1752篇 |
口腔科学 | 301篇 |
临床医学 | 2106篇 |
内科学 | 2496篇 |
皮肤病学 | 168篇 |
神经病学 | 723篇 |
特种医学 | 803篇 |
外国民族医学 | 11篇 |
外科学 | 1335篇 |
综合类 | 2605篇 |
现状与发展 | 3篇 |
一般理论 | 1篇 |
预防医学 | 1082篇 |
眼科学 | 481篇 |
药学 | 1574篇 |
16篇 | |
中国医学 | 829篇 |
肿瘤学 | 1257篇 |
出版年
2024年 | 49篇 |
2023年 | 247篇 |
2022年 | 543篇 |
2021年 | 783篇 |
2020年 | 574篇 |
2019年 | 498篇 |
2018年 | 488篇 |
2017年 | 466篇 |
2016年 | 407篇 |
2015年 | 623篇 |
2014年 | 752篇 |
2013年 | 694篇 |
2012年 | 1090篇 |
2011年 | 1217篇 |
2010年 | 897篇 |
2009年 | 752篇 |
2008年 | 753篇 |
2007年 | 878篇 |
2006年 | 765篇 |
2005年 | 746篇 |
2004年 | 487篇 |
2003年 | 430篇 |
2002年 | 397篇 |
2001年 | 329篇 |
2000年 | 339篇 |
1999年 | 335篇 |
1998年 | 350篇 |
1997年 | 295篇 |
1996年 | 269篇 |
1995年 | 214篇 |
1994年 | 193篇 |
1993年 | 144篇 |
1992年 | 116篇 |
1991年 | 105篇 |
1990年 | 97篇 |
1989年 | 91篇 |
1988年 | 82篇 |
1987年 | 82篇 |
1986年 | 74篇 |
1985年 | 57篇 |
1984年 | 29篇 |
1983年 | 30篇 |
1982年 | 29篇 |
1981年 | 30篇 |
1980年 | 19篇 |
1978年 | 11篇 |
1977年 | 14篇 |
1976年 | 16篇 |
1975年 | 12篇 |
1930年 | 11篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
Serologic epidemiology of hepatitis B viral infection and observation on the immunologic effect of hepatitis B vaccine 总被引:1,自引:0,他引:1
Q Y Ge 《中华预防医学杂志》1988,22(2):92-94
12.
尼卡地平控制性降压对家犬脊髓血流的影响 总被引:2,自引:1,他引:1
目的 观察尼卡地平控制性降压对家犬脊髓血流的影响。方法 成年杂种犬 6只 ,体重 12 5~ 16kg ,以 2 5 %硫喷妥钠麻醉。股动脉置管监测MAP。以尼卡地平 8μg·kg 1·min 1持续静脉注射控制性降压。以激光多普勒血流仪测定脊髓血流 (SCBF)。结果 降压前MAP为 (12 5 7±10 6 )mmHg ,降压后为 (72 0± 11 2 )mmHg ,平均下降 4 2 8%。降压前SCBF为 (9 80± 1 0 5 )v ,降压后为 (8 0 4± 0 96 )v ,降低幅度为 18%。结论 尼卡地平控制性降压对SCBF影响较小 ,可安全用于脊髓手术。 相似文献
13.
14.
Elke Wezenberg Robert Jan Verkes Ge S F Ruigt Wouter Hulstijn Bernard G C Sabbe 《Neuropsychopharmacology》2007,32(6):1272-1283
Ampakines act as positive allosteric modulators of AMPA-type glutamate receptors and facilitate hippocampal long-term potentiation (LTP), a mechanism associated with memory storage and consolidation. The present study investigated the acute effects of farampator, 1-(benzofurazan-5-ylcarbonyl) piperidine, on memory and information processes in healthy elderly volunteers. A double-blind, placebo-controlled, randomized, cross-over study was performed in 16 healthy, elderly volunteers (eight male, eight female; mean age 66.1, SD 4.5 years). All subjects received farampator (500 mg) and placebo. Testing took place 1 h after drug intake, which was around Tmax for farampator. Subjects performed tasks assessing episodic memory (wordlist learning and picture memory), working and short-term memory (N-back, symbol recall) and motor learning (maze task, pursuit rotor). Information processing was assessed with a tangled lines task, the symbol digit substitution test (SDST) and the continuous trail making test (CTMT). Farampator (500 mg) unequivocally improved short-term memory but appeared to impair episodic memory. Furthermore, it tended to decrease the number of switching errors in the CTMT. Drug-induced side effects (SEs) included headache, somnolence and nausea. Subjects with SEs had significantly higher plasma levels of farampator than subjects without SEs. Additional analyses revealed that in the farampator condition the group without SEs showed a significantly superior memory performance relative to the group with SEs. The positive results on short-term memory and the favorable trends in the trail making test (CTMT) are interesting in view of the development of ampakines in the treatment of Alzheimer's disease and schizophrenia. 相似文献
15.
16.
WINOCOUR PH; KALUVYA S; BROWN L; FARRER M; MILLAR JP; NEIL HAW; ALBERTI KGMM 《QJM : monthly journal of the Association of Physicians》1991,79(3):539-560
Hyperinsulinaemia is said to be a risk factor for cardiovasculardisease, but the extent to which different insulinaemic measuresare associated with vascular risk factors in ostensibly healthyindividuals, and whether they operate independently in men andwomen, remains uncertain. The association between risk factors and various insulinaemicmeasures was examined in 148 men and 118 women who were normoglycaemic,normotensive, and non-obese (body mass index in men <27,in women <25). A 75 g glucose tolerance test was administeredafter blood sampling for fibrinogen, lipids, lipoproteins andinsulin. Insulin was also measured after 1 and 2 hours. Significantunivariate correlations (p<0.01) were most consistently recordedbetween insulinaemic measures and fasting serum triglyceridesin men and women, whilst systolic blood pressure only correlatedwith insulinaemia in women, and diastolic blood pressure correlatedwith fasting and 2 hour insulinaemic measures in men and women.Inconsistent associations were noted with total serum cholesterolin men and women, with high density lipoprotein cholesterol,body mass index, apoprotein B and A1 in men, and with fibrinogenin women. Age was not correlated with any insulinaemic measurein men or women. Differences in vascular risk factors between quintiles of theinsulinaemic measures were examined, after correction for bodymass index. The dominant association with fasting and post-glucoseload insulinaemic measures was with triglycerides, especiallyin women, with less frequent graded differences between quintilesobserved for total cholesterol, and diastolic and systolic bloodpressures in men and women. The incidence of other risk factors often only differed in thelowest or highest quintile in comparison to other quintiles,suggesting a threshold rather than a graded effect. Furthermore,differences in HDL cholesterol and apoprotein B were only recordedfor top quintiles of post-glucose challenge/integrated insulinaemicmeasures in men, whilst serum fibrinogen concentrations onlydiffered significantly in women in the top insulinaemic areaunder the curve quintile. In the absence of additional risk factors such as diabetes,hypertension and obesity, insulinaemic measures are not consistentlyrelated to blood pressure and measures of lipid metabolism andcoagulation, and are thus a weak predictor of other cardiovascularrisk factors. The vascular risk profile associated with insulinappears somewhat different in apparently healthy men and women. 相似文献
17.
支气管动脉灌注化疗联合直线加速器放射治疗Ⅲa期非小细胞肺癌 总被引:1,自引:1,他引:0
目的 研究支气管动脉灌注化疗联合直线加速器放射治疗Ⅲa期非小细胞肺癌 (NSCLC)的可行性及临床价值。方法 76例NSCLC患者随机分成A、B 2组 ,A组先行 2次支气管动脉灌注化疗 (BAI) ,第 2次BAI 1~ 2周后再行直线加速器放射治疗 (RT) ;B组单纯行 2次BAI (对照组 )。结果 临床疗效 ,A组 (BAI RT)和B组 (BAI)分别为 89.47%和 60 .5 3% (Ρ <0 .0 1) ;1、3年生存率 ,A、B组分别为 81.5 8%、5 0 .0 0 %和 60 .5 3%、2 1.0 5 % ( 0 .0 1<Ρ <0 .0 5 )。结论 支气管动脉灌注化疗联合直线加速器放射治疗Ⅲa期非小细胞肺癌的临床疗效和患者 1、3年生存率均显著提高 相似文献
18.
19.
20.
Summary— Acidosis affects multiple steps in the excitation-contraction coupling pathway of myocardium, producing decreased calcium sensitivity of myofibrils and modification of the function of the sarcoplasmic reticulum. Our aim was to evaluate the effectiveness of three different classes of inotropic agents under acidotic conditions: 1) forskolin, an adenylate cyclase activator that enhances cellular cyclic AMP concentrations, 2) elevated extracellular Ca2+ and 3) endothelin-1, an activator of the inositol triphosphate, diacylglycerol pathway. Ferret papillary muscles were mounted in organ baths containing normal physiological solution (pH = 7.4). After baseline tension was measured, the muscles were bathed in an acidotic solution (pH = 6.98) that decreased tension to 40% of the control; subsequently, the muscles were washed with normal physiological solution until they returned to baseline. Each inotropic agent was added to the bathing solution in a concentration sufficient to increase tension by 40% above the baseline. Then the solution was made acidotic (pH = 6.98) in the continuous presence of that concentration of inotropic agent and the resultant steady-state developed tension measured. The increases in tension induced by each inotropic agent at normal pH were adjusted to be similar; in contrast, the response to each drug in acidosis was significantly different. Under acidotic conditions, endothelin-1 was the most effective inotropic agent in restoring the depressed developed tension. This was possibly due to enhancement of the myofilament sensitivity to Ca2+ , which was more effective than increasing [Ca2+ ]i through elevating extracellular Ca2+ or the addition of forskolin which increased [Ca2+ ]i but desensitized the myofilaments to Ca2+ . 相似文献