全文获取类型
收费全文 | 2020篇 |
免费 | 204篇 |
出版年
2022年 | 18篇 |
2021年 | 41篇 |
2019年 | 25篇 |
2018年 | 39篇 |
2017年 | 34篇 |
2016年 | 39篇 |
2015年 | 69篇 |
2014年 | 64篇 |
2013年 | 83篇 |
2012年 | 138篇 |
2011年 | 113篇 |
2010年 | 78篇 |
2009年 | 57篇 |
2008年 | 82篇 |
2007年 | 76篇 |
2006年 | 79篇 |
2005年 | 65篇 |
2004年 | 57篇 |
2003年 | 62篇 |
2002年 | 58篇 |
2001年 | 49篇 |
2000年 | 46篇 |
1999年 | 41篇 |
1998年 | 24篇 |
1997年 | 18篇 |
1996年 | 16篇 |
1995年 | 23篇 |
1994年 | 21篇 |
1992年 | 33篇 |
1991年 | 37篇 |
1990年 | 41篇 |
1989年 | 33篇 |
1988年 | 48篇 |
1987年 | 34篇 |
1986年 | 27篇 |
1985年 | 37篇 |
1984年 | 28篇 |
1983年 | 26篇 |
1982年 | 24篇 |
1981年 | 18篇 |
1980年 | 15篇 |
1979年 | 25篇 |
1977年 | 19篇 |
1976年 | 16篇 |
1975年 | 27篇 |
1974年 | 31篇 |
1973年 | 27篇 |
1972年 | 17篇 |
1971年 | 14篇 |
1968年 | 16篇 |
排序方式: 共有2224条查询结果,搜索用时 78 毫秒
91.
Amar Chatterjee 《Prostaglandins & other lipid mediators》1976,12(4):525-534
A comparative assessment of the efficacy of prolactin or HCG in reversing the luteolytic property of a single dose (2.0 mg/kg) of PGF2a was conducted in pregnant (day 10) rats. It was found that prolactin maintained pregnancy in 90% of the test animals. HCG though found to maintain pregnancy in 70% of the PGF2a-treated pregnants, the fetal survival rate was, however, recorded to be 62% against the control value of 98%. Conversely, prolactin replacement maintained the fetal survival rate as high as 93.4%. Moreover, the growth of the fetuses, placentae and corpus luteum in the pregnants having prolactin in conjunction with PGF2a was also found to be greater compared to the animals which h ad a combined regimen of PGF2a and HCG, but identical to controls. On the other hand, similar combined regimen when applied to hysterectomized pregnant rats, it was observed that though the vaginal diestrus was maintained by the prolactin or HCG in the presence of PGF2a, the prolactin regimen was found to be superb compared to HCG in the maintenance of luteal weight and functional activity. It was concluded that the antifertility effect of PGF2a in the rat is primarily the consequence of luteolysis and prolactin seems to be a much more appropriate hormonal replacement compared to HCG, a long-acting LH, in antagonizing the luteolytic property of PGF2a. 相似文献
92.
93.
94.
95.
Studies have been carried out on the glycosphingolipids of human KB cells grown in monolayer and suspension culture, and by synchronization of the latter with a double thymidine (2mM) block. Glycosphingolipids were identified tentatively by thin layer chromatography, gas-liquid chromatography, and combined gas-liquid chromatography and mass spectrometry. The predominant gangliosides in the these cells were AcNeu-Gal-Glc-Cer and AcNeu-Gal-GalNAc-Gal-(AcNeu). Glc-Cer. Theprincipal neutral glycosphingolipids were Glc-Cer, Gal-Glc-Cer, Gal-Gal-Glc-Cer, and GalNAc-Gal-Gal-Glc-Cer. Incubation of KB cells (grown in monolayer and subsequently in suspension culture) for 48 hours with D-[1-14Clgalactose resulted in appreciable incorporation of radioactivity into all of the principal glycosphingolipids of these cells. These experiments confirmed that KB cells are capable of synthesizing their constituent glycosphingolipids. KB cells grown in suspension culture showed A 2- to 3-fold increase inthe concentration of Glc-Cer, Gal-Glc-Cer, GalNAc-Gal-Gal-Glc-Cer, and AcNeu-Gal1NAc-Gal-Gal-Glc-Cer, and AcNeu-Gal-Ga1NAcGal-(AcNeu)-Glc-Cer. Thus, the occurrence of tissue culture-dependent changes in the level of glycosphingolipids is demonstrated. Perhaps messages governing the synthesis of glycosphingolipids are translated earlier in thecell cycle under certain conditions of growth and are affected by cell-cell contact and cell adhesion. 相似文献
96.
From the yellow flowers of Chrysanthemum indicum, a new flavone glycoside, acacetin 7-O-β-d-galactopyranoside was isolated and its structure established from spectral evidence and synthesis. 相似文献
97.
98.
99.
Bornali Chakrabarti Hridoy R Bairagya Deepak Kr Mishra Pradip Kumar Chatterjee Bishnu P Mukhopadhyay 《Bioinformation》2013,9(3):126-133
Human matrix metalloproteinase-8 (hMMP-8) plays a important role in the progression of colorectal cancer, metastasis, multiple
sclerosis and rheumetoid arthritis. Extensive MD-simulation of the PDB and solvated structures of hMMP-8 has revealed the
presence of few conserved water molecules around the catalytic and structural zinc (ZnC and ZnS) ions. The coordination of two
conserved water molecules (W and WS) to ZnS and the H-bonding interaction of WS to S151 have indicated the plausible involvement
of that metal ion in the catalytic process. Beside this the coupling of ZnC and ZnS metal ions (ZnC – WH (W1)…..W2 ….H162 - ZnS)
through two conserved hydrophilic centers (occupied by water molecules) may also provide some rational on the recognition of
two zinc ions which were separated by ~13 Å in their X-ray structures. This unique recognition of both the Zn+2 ions in the enzyme
through conserved water molecules may be implemented/ exploited for the design of antiproteolytic agent using water mimic
drug design protocol. 相似文献
100.
Mahalakshmi Vijayaraghavan Sengupta Prattusha Sumantran V. N. Suganya Natarajan Chatterjee Suvro 《Cell and Tissue Biology》2020,14(6):448-457
Cell and Tissue Biology - Besides disease condition, very few stress stimulants were determined to provoke red blood cell (RBC) adhesion to endothelial cells (EC). However, the possible role of... 相似文献