全文获取类型
收费全文 | 1263840篇 |
免费 | 94821篇 |
国内免费 | 1578篇 |
专业分类
耳鼻咽喉 | 16313篇 |
儿科学 | 41002篇 |
妇产科学 | 34947篇 |
基础医学 | 189390篇 |
口腔科学 | 34731篇 |
临床医学 | 117754篇 |
内科学 | 247813篇 |
皮肤病学 | 27278篇 |
神经病学 | 101849篇 |
特种医学 | 46761篇 |
外国民族医学 | 265篇 |
外科学 | 178580篇 |
综合类 | 25749篇 |
现状与发展 | 3篇 |
一般理论 | 568篇 |
预防医学 | 104654篇 |
眼科学 | 28044篇 |
药学 | 92557篇 |
7篇 | |
中国医学 | 2022篇 |
肿瘤学 | 69952篇 |
出版年
2018年 | 13531篇 |
2017年 | 10391篇 |
2016年 | 11324篇 |
2015年 | 13079篇 |
2014年 | 17999篇 |
2013年 | 27477篇 |
2012年 | 37573篇 |
2011年 | 39967篇 |
2010年 | 23053篇 |
2009年 | 22250篇 |
2008年 | 37753篇 |
2007年 | 40381篇 |
2006年 | 39963篇 |
2005年 | 39099篇 |
2004年 | 37544篇 |
2003年 | 35955篇 |
2002年 | 34866篇 |
2001年 | 56032篇 |
2000年 | 57043篇 |
1999年 | 48097篇 |
1998年 | 13397篇 |
1997年 | 12222篇 |
1996年 | 12644篇 |
1995年 | 11914篇 |
1994年 | 11107篇 |
1993年 | 10399篇 |
1992年 | 38198篇 |
1991年 | 37672篇 |
1990年 | 36446篇 |
1989年 | 35258篇 |
1988年 | 32691篇 |
1987年 | 32031篇 |
1986年 | 30524篇 |
1985年 | 28787篇 |
1984年 | 21944篇 |
1983年 | 19193篇 |
1982年 | 11366篇 |
1981年 | 10322篇 |
1979年 | 20945篇 |
1978年 | 15393篇 |
1977年 | 12790篇 |
1976年 | 11846篇 |
1975年 | 12811篇 |
1974年 | 15589篇 |
1973年 | 15363篇 |
1972年 | 14512篇 |
1971年 | 13552篇 |
1970年 | 12786篇 |
1969年 | 12065篇 |
1968年 | 11230篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
151.
Data on 232 members of a single pedigree, descended from two pairs of original parents, were made available to the participants of Genetic Analysis Workshop 8 (GAW8). In addition to information concerning age and sex, measurements for 10 quantitative traits and genotypes at 22 polymorphic marker loci were also provided for a subset of 193 of these family members. © 1993 Wiley-Liss, Inc. 相似文献
152.
153.
A E van der Merwe F J Mattheyse M Bedford P D van Helden D J Rossouw 《Burns : journal of the International Society for Burn Injuries》1990,16(3):193-197
Cultured keratinocytes were used as allografts on burn wounds in two patients. In both patients successful covering of the wounds was obtained. DNA fingerprinting of the epidermis covering the wounds 21 days later showed that the cultured keratinocytes were replaced by the patients' cells. 相似文献
154.
M Parry-Billings B Leighton G D Dimitriadis J Bond E A Newsholme 《Biochemical pharmacology》1990,40(5):1145-1148
The effects of physiological and pathological concentrations of glucocorticoids were investigated using the glucocorticoid antagonist RU486 and the synthetic glucocorticoid dexamethasone, respectively. The effects of these treatments on the concentrations of glutamine and other amino acids in skeletal muscle and plasma and on the rates of release of glutamine and alanine from incubated preparations of skeletal muscle of the rat were investigated. Dexamethasone treatment increased the concentration of glutamine and the rate of release of this amino acid from incubated soleus muscle preparations. This treatment decreased the concentration of glutamine in both gastrocnemius and EDL muscles, but was without effect on the rate of glutamine release from EDL muscles. In contrast, administration of the glucocorticoid antagonist RU486 decreased the rate of glutamine release from muscle. It is concluded that glucocorticoids have marked effects on the metabolism of glutamine by skeletal muscle per se and that these hormones may be important in the control of the rate of glutamine release from muscle in both physiological and pathological conditions. 相似文献
155.
In experiments on albino rats it was established that three administrations of indomethacin in a dose of 0.01 g/kg body weight induced a severe damage of the liver characterized by disturbances of hepatocytic membranes, bile-producing and protein-producing functions of the liver, an enhancement of lipid peroxidation, a decrease of reduced glutathione pool. Antioxidants (tocopherol acetate, essentiale, legalon, flacumin) limit manifestations of indomethacin, hepatotoxicity, as a result of which tha functional-biochemical disorders in the liver show up to a lesser degree. During the combined use of antioxidants in indomethacin-induced lesions of the liver their hepatoprotective activity increases. 相似文献
156.
PCP and related compounds inhibit 3H-mazindol binding to the cocaine receptor on dopamine transporters. The relative potencies of these compounds are such that some of the behavioral effects of PCP could be related to its action at the cocaine receptor; however, the affinity of PCP at the cocaine site (Ki = 1.59 microM) is less than its affinity at its own receptor (Ki about 0.12 microM). More data will be needed to conclusively implicate the cocaine receptor in the action of PCP. 相似文献
157.
Neuromuscular junctions (NJs) of fin muscles of teleostean fishes, Lebistes reticulatus, were ultrastructurally analyzed during 60 min of chronic exercise and a subsequent period of 90 min of induced recovery. NJs from 30-min-exercised fishes showed an almost complete depletion of synaptic vesicles (SVs), corresponding to 83% of SV consumption; 76% of axon terminals were branched at the end of this period. During the recovery period, it was possible to observe the reversibility of the changes induced by the exercise and the transitory events that lead to the reacquirement of the normal NJ morphology. After 15 min of rest, SV population increased to a value of 54.6 SVs/micron2 and the percentage of branched axons was 66.5%. At 60 min of recovery the number of SVs reached a value of 84.6 SVs/micron2. The SV population was fully reestablished at 80 min of rest, while the percentage of branched axons was found within normal ranges after 90 min of recovery. These results demonstrate that chronic exercise induced physiological depletion of NJ SVs and other axon terminal morphological changes, as well as that postexercise rest induces the reestablishment of the normal NJ morphology. 相似文献
158.
159.
160.
Facilitated uptake of zinc into human erythrocytes. Relevance to the treatment of sickle-cell anaemia 总被引:1,自引:0,他引:1
R C Hider L Ejim P D Taylor R Gale E Huehns J B Porter 《Biochemical pharmacology》1990,39(6):1005-1012
The ability of a number of heterocyclic metal chelators to deliver zinc into red cells, to release the liganded zinc to haemoglobin and thereby cause a left shift in the oxygen dissociation curve of intact red cells has been investigated. Incubation of neutrally charged zinc-pyrone and zinc-pyridin-2-one complexes with red cells led to the rapid accumulation of zinc within cells, whereas unliganded zinc in the form of zinc acetate, zinc chloride or zinc sulphate accumulated only slowly. The rate at which zinc was delivered to red cells by pyrone and pyridin-2-one ligands increased with increasing lipid solubility of the ligands. The uptake of zinc into both normal adult and sickle red cells was associated with a dose-dependent increase in the oxygen affinity of haemoglobin. The degree of left shift in the oxygen dissociation curve following the incubation of red cells with zinc-pyrone and -pyridin-2-one complexes suggests that these complexes may find application as agents to increase the oxygen affinity of haemoglobin in sickle cell disease and thereby decrease the probability of intravascular sickling at low tissue oxygen tensions. Ethylmaltol appears to be a particularly useful agent due to its known low toxicity. 相似文献