全文获取类型
收费全文 | 6896篇 |
免费 | 608篇 |
国内免费 | 1篇 |
专业分类
7505篇 |
出版年
2022年 | 46篇 |
2021年 | 101篇 |
2020年 | 68篇 |
2019年 | 89篇 |
2018年 | 110篇 |
2017年 | 97篇 |
2016年 | 175篇 |
2015年 | 258篇 |
2014年 | 289篇 |
2013年 | 348篇 |
2012年 | 457篇 |
2011年 | 445篇 |
2010年 | 298篇 |
2009年 | 220篇 |
2008年 | 347篇 |
2007年 | 337篇 |
2006年 | 371篇 |
2005年 | 341篇 |
2004年 | 339篇 |
2003年 | 295篇 |
2002年 | 271篇 |
2001年 | 108篇 |
2000年 | 114篇 |
1999年 | 111篇 |
1998年 | 91篇 |
1997年 | 54篇 |
1996年 | 63篇 |
1995年 | 65篇 |
1994年 | 64篇 |
1993年 | 74篇 |
1992年 | 68篇 |
1991年 | 66篇 |
1990年 | 63篇 |
1989年 | 55篇 |
1988年 | 50篇 |
1987年 | 43篇 |
1986年 | 43篇 |
1985年 | 47篇 |
1984年 | 66篇 |
1983年 | 43篇 |
1982年 | 57篇 |
1981年 | 55篇 |
1980年 | 51篇 |
1979年 | 39篇 |
1978年 | 39篇 |
1977年 | 43篇 |
1975年 | 37篇 |
1974年 | 38篇 |
1973年 | 50篇 |
1969年 | 33篇 |
排序方式: 共有7505条查询结果,搜索用时 15 毫秒
41.
Histochemical studies on urate oxidase in several mammals with special reference to uricolytic ability of primates 总被引:1,自引:0,他引:1
Summary Strong reactivity for urate oxidase was found in the liver parenchymal cells of the prosimians (i.e. the tree shrew, slow loris, potto and galago) as well as those of lower mammals. The liver parenchymal cells of the platyrrhine monkeys (i.e. the marmoset, owl monkey, squirrel monkey, capuchin monkey and spider monkey) were moderately positive. There was no preferential distribution of granular reaction products in zones of liver lobules of these species. The prosimians and platyrrhine monkeys seem to be uricolytic as lower mammals are. On the other hand, the old world monkeys (i.e. Java monkey and rhesus monkey) and the apes (i.e. the orang-utan and chimpanzee) were histochemically negative. 相似文献
42.
43.
T. R. Shanthaveerappa Morton B. Waitzman Geoffrey H. Bourne 《Histochemistry and cell biology》1966,7(1):80-95
Summary Detailed studies on phosphorylase localization in various components of the eyeball of rabbit and squirrel monkey have been made. Corneal epithelium, endothelium, and stromal cells, extrinsic and intrinsic muscles of the eyeball, ciliary process, endothelial cells of the anterior chamber angle, vitreal cells, lens epithelium, inner segment of cones; plexiform layer, ganglion cell layer, internal and external limiting membrane and Muller cells show high phosphorylase activity. Surprisingly, we observed phosphorylase activity inside the nucleus in the posterior 2 to 3 layers of corneal epithelium. The significance of phosphorylase localization in relation to glycogen distribution in various components of the eyeball and their energy requirements is stressed. 相似文献
44.
45.
46.
Geoffrey Dean 《BMJ (Clinical research ed.)》1959,2(5156):852-857
47.
Marion Barclay R. K. Barclay V. P. Skipski Olga Terebus-Kekish C. H. Mueller Ellen Shah W. L. Elkins 《The Biochemical journal》1965,96(1):205-209
1. Lipoproteins were measured in sera from 11 young women having a similar environment and diet. Sera were obtained at weekly intervals over a 12-week period. The values of the lipoproteins during periods in the normal ovulatory cycle were compared to assess their relation to reported hormone concentrations in blood. 2. Only the 4–0sf (HDL2) (d 1·125 sodium chloride) fraction changed significantly; it increased at ovulation in ten of the 11 subjects and fell as menstruation approached. 3. There was greater variability in most of the low-density rather than the high-density lipoproteins within individuals. The lipoprotein class most characteristic for an individual was the 4–0sf or HDL2 fraction. 相似文献
48.
Geoffrey Myddelton 《BMJ (Clinical research ed.)》1965,2(5456):304-305
49.
50.
Sensory interaction and sensory adaptation in short- and long-lasting space flights (SF) and the dynamics of stability of adaptive shifts were studied by the phenomenology of spontaneous and visually induced illusory reactions. It was shown that perceptive impairment developed during the initial adaptation to microgravity should be considered regular reactions of sensory systems under given environmental conditions rather than special features of the individuals examined. The classification of spontaneous illusory reactions (SIR) under conditions of microgravity and the results of investigation of the vertical vection (vection is a visual illusion evoked by the optokinetic stimulation) are presented. The following previously unknown phenomena were registered for the first time: inversion of the vertical vection illusion (VVI) evoked by vertical and sinusoidal optokinetic stimulation, impairment of perception of the body schema during VVI, change in the character of VVI, and development of VVI asymmetry. During long-lasting existence under conditions of weightlessness the anomalous perceptive reactions continued to be registered episodically (the period of adaptation was replaced by that of deadaptation). A hypothesis was suggested for the possible mechanisms of the phenomena found. [Translated from Fiziologiya Cheloveka, vol. 21, no. 4, p. 50-62, July-August, 1995] 相似文献