全文获取类型
收费全文 | 843篇 |
免费 | 64篇 |
出版年
2021年 | 17篇 |
2020年 | 14篇 |
2018年 | 13篇 |
2017年 | 14篇 |
2016年 | 19篇 |
2015年 | 29篇 |
2014年 | 25篇 |
2013年 | 33篇 |
2012年 | 49篇 |
2011年 | 50篇 |
2010年 | 29篇 |
2009年 | 14篇 |
2008年 | 27篇 |
2007年 | 35篇 |
2006年 | 28篇 |
2005年 | 20篇 |
2004年 | 20篇 |
2003年 | 25篇 |
2002年 | 18篇 |
2001年 | 22篇 |
2000年 | 13篇 |
1999年 | 15篇 |
1998年 | 7篇 |
1995年 | 6篇 |
1994年 | 12篇 |
1993年 | 7篇 |
1992年 | 31篇 |
1991年 | 21篇 |
1990年 | 17篇 |
1989年 | 13篇 |
1988年 | 14篇 |
1987年 | 16篇 |
1986年 | 14篇 |
1985年 | 18篇 |
1984年 | 8篇 |
1983年 | 10篇 |
1982年 | 8篇 |
1981年 | 8篇 |
1979年 | 10篇 |
1978年 | 10篇 |
1977年 | 6篇 |
1976年 | 8篇 |
1975年 | 10篇 |
1974年 | 10篇 |
1973年 | 9篇 |
1971年 | 12篇 |
1970年 | 6篇 |
1969年 | 9篇 |
1968年 | 10篇 |
1964年 | 9篇 |
排序方式: 共有907条查询结果,搜索用时 15 毫秒
901.
902.
H S Bhatti S Bhushnurmath R C Mahajan N K Ganguly R Sehgal 《Experimental parasitology》1992,74(3):283-289
Among the wide variety of clinicopathological manifestations of intestinal amebiasis, amebomas occur rarely and their pathogenesis is not well understood. When cholesterol-fed, 2- to 4-week-old guinea pigs were infected intracecally with a virulent, monoaxenic strain of Entamoeba histolytica, gross and histologically characteristic amebomas developed in 85% of the animals by the 3rd day, in 94% by the 9th day, and in 96% by the 12th day postinfection, by which time most of them had died. Amebomas were confirmed by histopathology. Thus, a model of consistent production of amebomas was documented. 相似文献
903.
904.
A new neolignan designated (?)-maglifloenone and the known one futoenone, both of which contain the rarely occurring spirocyclohexadienone skeleton, have been isolated together with the tetrahydrofuranolignan (+)-veraguensin, an optically inactive tertiary base taspine and β-sitosterol from the leaves and twigs of Magnolia liliflora. The structure and stereochemistry of (?)-maglifloenone have been deduced from the spectral data and the mass fragmentation of (?)-maglifloenone and futoenone have been rationalized. This is the first report of two neolignans of spirocyclohexadienone skeleton and of taspine from the Magnoliaceae family and the second report of the natural occurrence of futoenone. 相似文献
905.
Studies on metabolism of vitamin A. The effect of the stage of vitamin A deficiency on sulphate activation in rat liver 总被引:2,自引:2,他引:0
1. The synthesis of ;active sulphate' in rat liver was studied at various stages of vitamin A deficiency, with the corresponding pair-fed controls. 2. The activity was significantly decreased even at the onset of the deficiency, and at the acute stage there was further loss. 3. Only at the earlier stages of the deficiency was the addition of retinol, in vitro, fully effective in restoring the lost activity; retinoic acid was partially active. No such restoration was possible at the acute deficiency stage. 相似文献
906.
N. Kaul K. I. Andrabi N. K. Ganguly P. L. Wahi 《Molecular and cellular biochemistry》1993,120(1):81-85
Administration of nifedipine to mice over a period of six months caused a significant (p<0.05) decrease in neutrophilic functions viz superoxide generation, coupled to NADPH oxidase activity as well as NADPH production by HMP shunt. Properties like chemotaxis and phagocytosis showed a similar decrease. From this study, it is seen that nifedipine causes neutrophil functional abrogation which is therefore an apparent concern for the prolonged usage of the drug. However, relevance of the mouse model to clinical situation needs further investigation. 相似文献
907.
Rubicoumaric acid and rubifolic acid isolated from Rubia cordifolia have been shown to be 30-hydroxy-3β-p-hydroxycoumaryloxy-urs-12-ene-28-oic acid and 3β,30-dihydroxy-urs-12-ene-28-oic acid(30-hydroxyursolic acid) respectively on the basis of 1H NMR, 13C NMR and mass spectral and chemical evidence. 相似文献