全文获取类型
收费全文 | 17750篇 |
免费 | 1276篇 |
国内免费 | 577篇 |
专业分类
耳鼻咽喉 | 81篇 |
儿科学 | 218篇 |
妇产科学 | 169篇 |
基础医学 | 1130篇 |
口腔科学 | 612篇 |
临床医学 | 1732篇 |
内科学 | 2822篇 |
皮肤病学 | 407篇 |
神经病学 | 874篇 |
特种医学 | 721篇 |
外科学 | 2145篇 |
综合类 | 1784篇 |
现状与发展 | 1篇 |
预防医学 | 852篇 |
眼科学 | 165篇 |
药学 | 4298篇 |
4篇 | |
中国医学 | 351篇 |
肿瘤学 | 1237篇 |
出版年
2023年 | 203篇 |
2022年 | 343篇 |
2021年 | 636篇 |
2020年 | 603篇 |
2019年 | 605篇 |
2018年 | 626篇 |
2017年 | 595篇 |
2016年 | 646篇 |
2015年 | 673篇 |
2014年 | 991篇 |
2013年 | 1711篇 |
2012年 | 966篇 |
2011年 | 1050篇 |
2010年 | 834篇 |
2009年 | 773篇 |
2008年 | 760篇 |
2007年 | 782篇 |
2006年 | 653篇 |
2005年 | 659篇 |
2004年 | 547篇 |
2003年 | 516篇 |
2002年 | 420篇 |
2001年 | 357篇 |
2000年 | 315篇 |
1999年 | 261篇 |
1998年 | 239篇 |
1997年 | 272篇 |
1996年 | 184篇 |
1995年 | 195篇 |
1994年 | 171篇 |
1993年 | 177篇 |
1992年 | 157篇 |
1991年 | 156篇 |
1990年 | 118篇 |
1989年 | 133篇 |
1988年 | 133篇 |
1987年 | 136篇 |
1986年 | 119篇 |
1985年 | 121篇 |
1984年 | 112篇 |
1983年 | 75篇 |
1982年 | 82篇 |
1981年 | 77篇 |
1980年 | 68篇 |
1979年 | 62篇 |
1978年 | 51篇 |
1977年 | 51篇 |
1976年 | 46篇 |
1975年 | 28篇 |
1973年 | 30篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
凝固酶阴性葡萄球菌检测在慢性前列腺炎中的意义 总被引:21,自引:0,他引:21
目的 研究慢性前列腺炎与凝固酶阴性葡萄球菌 (CNS)的关系 ,探讨前列腺液中CNS检测的临床意义。 方法 对 4 2 8例慢性前列腺炎患者采用Meares Stamey四段取样法作前列腺液细菌培养和药敏试验。患者年龄 18~ 4 6岁 ,平均 31岁。病程 3~ 32个月 ,平均 6个月。慢性前列腺炎症状指数 (NIH CPSI)平均 2 3.2分。 结果 4 2 8例均行细菌培养 ,其中 2 4 8例 (5 7.94 % )分离出细菌。革兰阳性菌 195例 (78.6 3% ) ,其中葡萄球菌 16 0例 (6 4 .5 2 % ,16 0 / 2 4 8) ,CNS 89例 (35 .89% ,89/ 2 4 8) ;CNS中以表皮葡萄球菌为主者 81例 (32 .6 6 % ) ,其次为腐生葡萄球菌 3例和溶血性葡萄球菌 2例 ;NIH CPSI积分与细菌培养结果无明显相关。CNS对常用抗菌药物 (β 内酰胺类、喹诺酮类、氨基糖苷类 )耐药率较高 (5 1.9%~ 10 0 % )。 结论 CNS为慢性前列腺炎的主要致病菌 ,应引起高度重视 ;适时监测前列腺液病原菌及药敏试验对临床诊断和治疗慢性前列腺炎具有重要意义。 相似文献
72.
目的 :探讨移植肝一氧化氮合酶的表达与急性排斥反应间关系及其细胞定位。方法 :应用近交系 BN至 Lew大鼠原位肝移植急性排斥反应及同基因 ( Lew- Lew)肝移植动物模型 ,用免疫组化法检测移植肝组织中诱导型一氧化氮合酶 ( i NOS)的表达。同时观察 i NOS抑制剂氨基胍和免疫抑制剂 FK5 0 6对肝移植术后急性排斥反应的影响。结果 :在急性排斥组 i NOS表达强阳性 ,与氨基胍组、FK5 0 6组及同基因对照组比较差异显著。结论 :在大鼠原位肝移植发生急性排斥反应时 i N-OS增高程度与排斥反应的强度有明显关系。氨基胍、FK5 0 6可以抑制 i NOS的表达。抑制 i NOS的表达可明显减轻移植肝组织的急性排斥反应 相似文献
73.
本文报道2-氧化-1,3,2-二氧磷杂环己烷类衍生物的合成,希望寻找效果较好的可逆性胆碱酯酶抑制剂。初步药理实验证明,所合成的大部分化合物具有一定的抑制乙酰胆碱酯酶的作用,且毒性较低。通过对中间体Ⅱ进行质谱分析,发现该类化合物中大部分存在M-57碎片离子峰,利用高分辨质谱和亚稳离子测定,确定了该碎片离子的生成过程。 相似文献
74.
75.
76.
利用仿生化学的原理,本文设计并合成了两个儿茶酚胺类和两个羟基吡啶酮类八配位的螯合剂,初步动物试验表明,具有较强的钚促排能力。 相似文献
77.
J. P. De La Cruz S. Cámara M. A. Frutos F. Sánchez De La Cuesta 《European journal of clinical pharmacology》1992,43(3):307-309
Summary The antiproteinuric effect of the antiplatelet agent dipyridamole has been assessed after inhibiton of thromboxane B2 (TxB2) synthesis in 8 patients with confirmed membranous glomerulonephritis.
There were three study periods, each of 30 days, and 45 days apart, namely a washout period, treatment with dipyridamole 300
mg/d, and dipyridamole 225 mg/d plus aspirin 150 mg/d. On Days 1 and 30 of each study period serum and urine creatinine, 24-h
excretion of protein, creatinine clearance, platelet aggregometry on whole blood and serum TxB2 were measured.
Treatment with dipyridamole alone or with aspirin produced significant inhibition of platelet aggregation and a fall in 24-h
protein excretion; the latter amounted to 54% with dipyridamole alone and 56 % with dipyridamole plus aspirin (NS). Dipyridamole
plus aspirin caused an 82 % reduction in serum TxB2. 相似文献
78.
In order to compare an acceleromyograph (TOF-GuardTM ) with a mechanomyograph (Grass FT03), the dose–response relationship of rocuronium was simultaneously determined in both arms of 15 children aged 3–11 years during anaesthesia with thiopentone, alfentanil and nitrous oxide. Three subgroups of five children received rocuronium 120, 180 or 240 μg.kg−1 randomly. The effective doses to produce 50% and 95% depression of the first twitch of the train-of-four determined by acceleromyography were 206 and 337 μg.kg−1 , respectively, while these values determined by mechanomyography were 151 and 331 μg.kg−1 , respectively. The dose–response curve obtained by acceleromyography was steeper and shifted to the right compared with that obtained by mechanomyography (p < 0.0001). The difference between the effective dose producing 50% twitch depression determined by the two devices was highly significant (p < 0.0001). In 13 out of 15 children, the acceleromyograph control train-of-four ratio was significantly greater than unity. Although there was a good correlation ( r = 0.85) between simultaneous pairs of measurements of neuromuscular block, the acceleromyograph exhibited a bias of −25% relative to the mechanomyograph with wide limits of agreement (−62 to +12%). We conclude that acceleromyographic and mechanomyographic measurements should not be used interchangeably when determining the potency of muscle relaxants. 相似文献
79.
Ropivacaine, a new long–acting amino–amide local anaesthetic agent, and bupivacaine, in various concentrations with or without addition of adrenaline, were tested in a randomized, double–blind study using intradermal wheals. Ten non–smoking, healthy, young male volunteers participated. In series I plain solutions of ropivacaine (0.25%, 0.5%, 0.75% and 1%) and bupivacaine (0.25%, 0.5% and 0.75%) were injected intradermally and in series II the same concentrations, with the addition of adrenaline 5 ug ml-1 ( 1 :200 000), were used. The same volunteers took part in both series, with an interval of at least three weeks between the experiments. Saline was included as control in both series. Pin–pricking was used to assess the dermal analgesia. Plain solutions of ropivacaine produced significantly longer durations of dermal analgesia than did plain solutions of bupivacaine, in all tested concentrations. A significant increase in duration was seen for both local anaesthetics when adding adrenaline. Local vascular effects at the injected areas were determined by visual inspection (nil, pink, pale). Local blanching (pale) was significantly more frequent for plain solutions of ropivacaine, in all tested concentrations. Local redness (pink) was significantly more frequent with plain bupivacaine, in a dose–dependent relation. An initial redness was frequently observed for both local anaesthetics containing adrenaline, followed by blanching at most sites. 相似文献
80.
Koji Tomobe Hajime Fujii Buxiang Sun Hiroshi Nishioka Okezie I Aruoma 《Biomedicine & Pharmacotherapy》2007,61(7):427-434
Oligonol is produced from the oligomerization of polyphenols (typically proanthocyanidin from a variety of fruits such as lychees, grapes, apples, persimmons, etc.) and contains catechin-type monomers and oligomers of proanthocyanidins. The ability of Oligonol to affect infection-dependent eye inflammation, locomotion and longevity in senescence-accelerated prone mice (SAMP8) (a model of senescence acceleration and geriatric disorders with increased oxidative stress and neuronal deficit) was investigated. Oligonol (60mg/kg) significantly modulated the extent of inflammation scores in the eye of SAMP8 mice. Examination of the mice indicated infection with mouse hepatitis virus and pinworm (Syphacia obvelata) in both males and females and with the intestinal protozoa (trichomonad) in males. A comparison of the two groups (using log-rank test) and the difference in the mean life span between groups (using Student's t-test) indicated significant differences in survival (p=0.043) and the mean life span (p=0.033) in male SAMP8 mice. Oligonol increased the mean life span and this was statistically significant. In the open-field locomotive test, the 7-week-old SAMP8 mice crossed more than 40 partitioned lines in 1min. At 48-week-old control untreated male SAMP8 crossed 2 lines. The Oligonol-treated 48-week-old male SAMP8 mice crossed 17 lines however. The improved locomotive activity was statistically significant even after 36weeks in the Oligonol-treated male SAMP8 but this was not the case throughout the time course of the study in the Oligonol-treated female SAMP8. Thus Oligonol treatment to SAMP8 mice modulated the severity of infection-dependent inflammation, prolonged life-span and significantly improved locomotive activity indicating potential benefit to aging-associated diseases such as Alzheimer's or Parkinson's diseases. This presents potential for further research to define infection-dependent inflammation associated with degenerative conditions and the molecular mechanism of dietary antioxidant protection. 相似文献