全文获取类型
收费全文 | 15332篇 |
免费 | 1074篇 |
国内免费 | 607篇 |
专业分类
耳鼻咽喉 | 50篇 |
儿科学 | 186篇 |
妇产科学 | 39篇 |
基础医学 | 1393篇 |
口腔科学 | 518篇 |
临床医学 | 1096篇 |
内科学 | 1665篇 |
皮肤病学 | 399篇 |
神经病学 | 841篇 |
特种医学 | 379篇 |
外国民族医学 | 1篇 |
外科学 | 756篇 |
综合类 | 2220篇 |
现状与发展 | 2篇 |
预防医学 | 699篇 |
眼科学 | 336篇 |
药学 | 5331篇 |
23篇 | |
中国医学 | 827篇 |
肿瘤学 | 252篇 |
出版年
2024年 | 22篇 |
2023年 | 135篇 |
2022年 | 297篇 |
2021年 | 537篇 |
2020年 | 450篇 |
2019年 | 400篇 |
2018年 | 387篇 |
2017年 | 401篇 |
2016年 | 445篇 |
2015年 | 428篇 |
2014年 | 892篇 |
2013年 | 1118篇 |
2012年 | 956篇 |
2011年 | 943篇 |
2010年 | 807篇 |
2009年 | 683篇 |
2008年 | 689篇 |
2007年 | 716篇 |
2006年 | 656篇 |
2005年 | 575篇 |
2004年 | 554篇 |
2003年 | 489篇 |
2002年 | 397篇 |
2001年 | 337篇 |
2000年 | 271篇 |
1999年 | 245篇 |
1998年 | 227篇 |
1997年 | 215篇 |
1996年 | 225篇 |
1995年 | 193篇 |
1994年 | 168篇 |
1993年 | 154篇 |
1992年 | 130篇 |
1991年 | 129篇 |
1990年 | 120篇 |
1989年 | 119篇 |
1988年 | 114篇 |
1987年 | 81篇 |
1986年 | 89篇 |
1985年 | 245篇 |
1984年 | 174篇 |
1983年 | 162篇 |
1982年 | 145篇 |
1981年 | 141篇 |
1980年 | 100篇 |
1979年 | 68篇 |
1978年 | 47篇 |
1977年 | 33篇 |
1976年 | 29篇 |
1975年 | 29篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
肝素钠软膏(海普林)治疗皮质类固醇激素依赖性皮炎疗效观察 总被引:3,自引:0,他引:3
目的观察肝素钠软膏(海普林)治疗皮质类固醇激素依赖性皮炎的效果。方法随机抽取部分病例组成对照组,其余病例组成治疗组,分别使用单纯乳剂和肝素钠软膏外涂,配合相关内服药物治疗,比较治疗组和对照组疗效。结果对照组治疗有效率为24.81%,治疗组治疗有效率为52.24%,两组结果差异有非常显著性。结论应用肝素钠软膏外用治疗皮质类固醇激素依赖性皮炎取得了满意的疗效。 相似文献
62.
用差速离心方法分离提取荷Lewis肺癌小鼠癌组织和肝组织富含溶酶体部分,并以溶酶体标志酶酸性磷酸酶(ACP)的游离酶和总酶活性比值作为观察溶酶体膜稳定性变化的指标,观察了亚硒酸钠对两种组织ACP酶活性和膜稳定性的影响。发现硒对癌组织和肝组织ACP活性的异常升高有抑制作用、稳定溶酶体膜,在癌瘤增殖前期作用明显(P<0.05)。提示这种拮抗效应与硒直接和间接的抗脂质过氧化有关。 相似文献
63.
The post-mortem diagnosis of acute myocardial ischaemia may be difficult to establish in the absence of morphological changes in the myocardium or recent coronary thrombosis. Ischaemic cell injury leads to potassium (K) efflux and sodium (Na) influx and, if the blood is still circulating, the K:Na ratio of the tissue falls. In this study, the K:Na ratio was measured by eluting the ions from samples of myocardium and assaying the eluate. The method yields similar results to those obtained by a previous method, in which myocardial samples were homogenized. The K:Na ratios on samples of horizontal slices through the heart were plotted on maps of the slices. A low K:Na ratio corresponded to, but extended beyond, areas where there was morphological evidence of ischaemia. The method is simple and may be of use in routine practice. 相似文献
64.
65.
为了寻找能够控制硝普钠释放的控释膜,研究了数种高分子膜的通透性,其中以经过热处理的聚乙烯醇(PVA)膜控制硝普钠释放性能较好。进一步研究了热处理条件对PVA膜通透性的影响,发现只要热处理的温度和时间恰当,就可以获得具有一定通透性的PVA膜。 相似文献
66.
Monitoring of skin response to sodium lauryl sulphate: clinical scores versus bioengineering methods
The present trial was designed to evaluate clinical scores (single observer) of sodium lauryl sulphate (SLS)-induced skin irritation in a group of subjects (n = 10) over a 10-day period along with various skin function parameters. In order to avoid significant variations due to secondary phenomena, the following parameters were recorded with non-invasive instruments in this order: skin capacitance (C1; arbitrary units; CM420 Corneometer), transepidermal water loss (TEWL; g/m2.h; Evaporimeter) and laser Doppler flowmetry (CBFV: cutaneous blood flow values; Periflux). All examinations were performed during winter on reclined relaxed subjects present for at least 10 min in a test room with controlled temperature and relative humidity (t degrees: 19.5-20.7 degrees C and RH: 47.3-60.3%). The analysis of differential data (delta = value at tx-value before test; 2-way ANOVA) was made on single parameters as a function of site (volar forearm versus neck) and time (from 24 h after 48-h occlusion with 5% SLS up to 10 days later). The profile of erythema scores over time differed between neck and forearm, but the delta CBFV readings with the laser Doppler instrument did not detect significant site-time interactions. Roughness (blind evaluation with palpating finger) and capacitance readings (delta C1) showed significant differences between sites, but the profile over time was similar in both locations. delta TEWL did not differ according to anatomical location. The reason for different erythema scores on neck and forearm might be related to inherent regional variation of optical properties of the skin or to a substantial contribution of SLS-induced roughness to the readings of erythema.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
67.
血卟啉衍生物(YHpD)合并照光对S180瘤细胞摄取~(86)Rb,瘤细胞的钠泵活性及糖酵解具有明显的抑制作用,且抑制程度随YHpD剂量的增大而增强。瘤细胞的总ATP酶和(Na-K)-ATP酶活性对YHpD的光动力效应也较敏感.YHpD对Mg—ATP酶活性有轻度抑制作用。YHpD并用哇巴因,对瘤细胞摄取~(86)Rb的光动力效应比两种药物单独应用的抑制作用大。 相似文献
68.
Stefan Farese Kushiar Shojaati Bert Kadereit Felix J Frey Markus G Mohaupt 《Nephrology, dialysis, transplantation》2006,21(7):1984-1987
Volume expansion in the presence of elevated aldosterone availabilityis a hallmark of normal pregnancy. Intravascular volume depletioncharacterizes severe pregnancy-associated disease conditionssuch as intra-uterine growth retardation, chronic hypertensionor pre-eclampsia [1]. Two hypotheses have been forwarded toexplain volume depletion in pregnancy: the first hypothesischarges inappropriate sensing of vascular overfilling,resulting in an increased transendothelial loss of fluid tothe extravascular compartment. In contrast, the second hypothesisfocuses on vascular underfilling due to inappropriatelylow aldosterone levels. The second hypothesis is based on theassumption that a compensatory increase in the circulating fluidvolume is required in normal pregnancy to support fetal substratedelivery. According to the second concept, maternal blood pressureincreases due to counter-regulatory mechanisms when placentalblood supply is reduced [2]. In support of the underfillinghypothesis are observations that a 相似文献
69.
A cohort mortality study among cobalt and sodium workers in an electrochemical plant 总被引:3,自引:0,他引:3
J M Mur J J Moulin M P Charruyer-Seinerra J Lafitte 《American journal of industrial medicine》1987,11(1):75-81
We have studied the mortality between 1950 and 1980 of a cohort of 1,143 workers in an electrochemical plant producing cobalt and sodium. The mortality of the whole cohort is significantly lower than in the French population for all causes of death (SMR = 0.77), and especially for deaths from circulatory system diseases (SMR = 0.59). However, among cobalt production workers, there is a relative over-mortality, especially from lung cancers (SMR = 4.66, 4 cases). The relationship between cobalt production and lung cancer mortality was supported by a case-control study nested in the cohort study. The authenticity of the occupational origin of this risk could not be established due to the low number of cases and because the role of tobacco consumption could not be taken into account. Other studies should be carried out in plants producing or using cobalt. 相似文献
70.