全文获取类型
收费全文 | 9352篇 |
免费 | 859篇 |
国内免费 | 254篇 |
专业分类
耳鼻咽喉 | 55篇 |
儿科学 | 223篇 |
妇产科学 | 189篇 |
基础医学 | 2045篇 |
口腔科学 | 180篇 |
临床医学 | 814篇 |
内科学 | 1477篇 |
皮肤病学 | 141篇 |
神经病学 | 871篇 |
特种医学 | 319篇 |
外科学 | 680篇 |
综合类 | 799篇 |
现状与发展 | 1篇 |
预防医学 | 1056篇 |
眼科学 | 114篇 |
药学 | 639篇 |
4篇 | |
中国医学 | 266篇 |
肿瘤学 | 592篇 |
出版年
2024年 | 18篇 |
2023年 | 173篇 |
2022年 | 316篇 |
2021年 | 481篇 |
2020年 | 458篇 |
2019年 | 389篇 |
2018年 | 379篇 |
2017年 | 377篇 |
2016年 | 339篇 |
2015年 | 386篇 |
2014年 | 620篇 |
2013年 | 698篇 |
2012年 | 493篇 |
2011年 | 553篇 |
2010年 | 429篇 |
2009年 | 452篇 |
2008年 | 395篇 |
2007年 | 390篇 |
2006年 | 331篇 |
2005年 | 260篇 |
2004年 | 313篇 |
2003年 | 200篇 |
2002年 | 205篇 |
2001年 | 174篇 |
2000年 | 134篇 |
1999年 | 157篇 |
1998年 | 121篇 |
1997年 | 134篇 |
1996年 | 101篇 |
1995年 | 91篇 |
1994年 | 88篇 |
1993年 | 74篇 |
1992年 | 79篇 |
1991年 | 52篇 |
1990年 | 67篇 |
1989年 | 57篇 |
1988年 | 51篇 |
1987年 | 38篇 |
1986年 | 36篇 |
1985年 | 65篇 |
1984年 | 60篇 |
1983年 | 32篇 |
1982年 | 41篇 |
1981年 | 38篇 |
1980年 | 25篇 |
1979年 | 18篇 |
1978年 | 16篇 |
1977年 | 13篇 |
1976年 | 16篇 |
1974年 | 7篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
脾脏切除对胸腺和淋巴结免疫功能的影响 总被引:4,自引:0,他引:4
报道脾脏切除(脾切)对动物胸腺和淋巴结免疫功能的影响,脾切后3w大鼠胸腺细胞自发增殖及ConA诱导增殖均无明显变化,ConA诱导淋巴结细胞增殖脾切组明显高于假手术对照组,脾切后3w再用SRBC免疫,5d后小鼠腹腔淋巴结数量脾切明显高于对照组,用QHS法测定淋巴结细胞对SRBC初次抗体产生脾切组则明显低于对照组。 相似文献
32.
O. D. Golenko E. E. Batrak M. F. Kharchenko 《Bulletin of experimental biology and medicine》1998,125(3):282-285
Inhibitory effect of glycosaminoglycans isolated from peripheral blood granulocytes of patients with chronic myeloleukemia
and normal subjects on increment in colony-forming units of fibroblasts in monolayer cultures of rat bone marrow is determined
by the degree of sulfation of their main component chondroitin-4-sulfate and by increased content of heparan sulfate.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 125, No. 3, pp. 319–322, March, 1998 相似文献
33.
ABSTRACT. The effects of procedures which stimulate sympathetic activity, viz. mental stress induced by a colour-word conflict test (CWT) for 20 min, and orthostasis (ORT) for 8 min were studied in 8 young (16-20 yr) insulin-dependent diabetes mellitus (IDDM) patients and 9 age and sex-matched healthy controls. The IDDM patients showed no signs of neuropathy or retinopathy and their mean HbA1c value was 8.4 ±0.6% (normal value < 5.0 %). Blood pressure and heart rate increased significantly during CWT and ORT in both groups. The changes in systolic blood pressure and heart rate were comparable in both groups during CWT; the IDDM group showed a higher ( p < 0.05) heart rate after 8 min of orthostasis, however. CWT and ORT elicited equivalent increases in noradrenaline in venous plasma in both groups ( p < 0.05), but the IDDM patients had 50% lower values ( p < 0.01) at rest, during CWT and at rest after CWT than controls. CWT and ORT evoked equivalent plasma adrenaline increases in both groups. The lipolysis marker, plasma glycerol, was about 40 % lower ( p < 0.05) in the IDDM group before and after CWT. Yet, mental stress evoked equivalent increases in glycerol levels ( p < 0.01) in both groups. These findings indicate that sympathetic activity in the young diabetic patients without signs of neuropathy may be blunted. 相似文献
34.
35.
Takashi Hineno M.D. Mutsuhiko Mizobuchi M.D. Oh-ichi Nishimatsu M.D. Jun Horiguchi M.D. Yasuo Kakimoto M.D. 《Psychiatry and clinical neurosciences》1994,48(3):583-587
Abstract: Studies on the circadian rhythm of urine excretion in healthy men have demonstrated that the maximal urine flow occurs in the early afternoon and the minimal around midnight. In this study, an abnormality in the variation of urine volume was found in parkinsonian patients. Urine samples were collected during daytime (9:00–21:00) and nighttime (21:00–9:00). Fifteen healthy control subjects were examined and found to excrete 60% during the daytime and 40% during the nighttime of the total urine volume. Sixteen parkinsonian patients excreted 43% during the daytime and 57% during the nighttime. In contrast to the control subjects, the parkinsonian patients excreted a smaller volume of their urine during the daytime than during the nighttime. This finding might be related to the degeneration of dopaminergic and/or nondopaminergic neurons in the brain which control urinary excretion. 相似文献
36.
目的 探讨神经系统疾病患者血小板参数的变化。方法 测定神经系统疾病患者血小板数(PLT)和平均血小板体积(MPV),并与对照组作比较。结果 与对照组比较,脑梗死、椎-基底动脉供血不足患者PLT明显减少,MPV明显增大;脑出血组MPV、PLT均减少。结论 血小板参数的变化对神经系统疾病的诊断、预防和治疗有重要的参考价值。 相似文献
37.
Pharmacokinetics of orally administered hexobarbital in plasma and saliva of healthy subjects 总被引:1,自引:0,他引:1
M van der Graaff N P Vermeulen P Heij J K Boeijinga D D Breimer 《Biopharmaceutics & drug disposition》1986,7(3):265-272
Hexobarbital (HB) concentrations were determined in plasma and saliva of 8 healthy subjects, following oral administration of 500 mg HB-Na. Mean plasma half-lives were 3.2 +/- 0.1 h, and salivary half-lives 3.3 +/- 0.2 h. Mean plasma clearance was 22.9 +/- 2.3 1 h-1. There was a linear relationship between HB concentrations in saliva and plasma (r = 0.92). Mean salivary levels were 34 per cent of plasma levels. Salivary pH was constant throughout the experiment, 7.06 +/- 0.09. There was an inconsistent tendency of the saliva over plasma ratios to increase as a function of time. The percentage of protein binding calculated from saliva over plasma ratios was in reasonable agreement with in vitro data of equilibrium dialysis, 64.1 +/- 2.6 per cent and 65.9 +/- 0.8 per cent, respectively. The experiment was repeated in 4 subjects, and considerable intraindividual differences were shown to exist in saliva over plasma ratio, half-lives, and protein binding. It was concluded that HB elimination half-lives can relatively accurately be determined from salivary concentrations. Oral plasma clearance can only be estimated if the individual saliva over plasma ratios are known; this would require the taking of at least one blood sample during the experiment. When employing HB as a model substrate for drug metabolizing enzyme activity in vivo, the determination of its pharmacokinetic parameters, particularly oral plasma clearance as a reflection of cytochrome P-450 activity, cannot be achieved by taking saliva samples only. 相似文献
38.
M. B. Regazzi R. Rondanelli E. Vida F. Farinelli R. A. Upton 《European journal of clinical pharmacology》1987,33(3):243-247
Summary Slower drug absorption at night can leave residual drug from an evening dose of a sustained-release product remaining to be absorbed at the time of the next morning's dose, thereby giving higher plasma concentrations of the drug during the day than the night.When a capsule product releasing theophylline over 12 h after a morning dose was given repetitively at 8 a.m. and 8 p.m. for 4 days, daytime plasma concentrations from 4 h to 8 h after the dose were about 40% greater than corresponding night-time concentrations, and the mean steady-state concentration during the night-time interval was only 81% of that during the daytime interval.Altering the regimen to one capsule at 12 noon and one at 10 p.m. eliminated all significant differences between a.m. and corresponding p.m. plasma concentrations of theophylline and between the mean steady-state concentrations for each of the interdose intervals within a day. 相似文献
39.
Foropenseverewoundandthewoundafterdebridement,mostscholarsthinkthewoundshouldbeclosedindelayedfirst-phase.Meshrelaxingshortincision(MRSI)methodcanclosemoreskindeficiencyandhightensionopenwound,andavoidsubcutaneoushematomaandskinflapdrift.Intheexperiment,theexperimentalmodelonrattensionskinflaphasbeeninvolved,andthecontentofendothelin(ET)inratskinflaptissuehasbeenmeasuredinvariousperiodofwoundhealingaftermeshedrelaxingshortincisionsuturewithimmunohistochemistry,inordertodiscussprobablemechani… 相似文献
40.