全文获取类型
收费全文 | 730篇 |
免费 | 74篇 |
专业分类
804篇 |
出版年
2023年 | 3篇 |
2022年 | 3篇 |
2021年 | 12篇 |
2020年 | 4篇 |
2019年 | 4篇 |
2018年 | 7篇 |
2017年 | 12篇 |
2016年 | 10篇 |
2015年 | 18篇 |
2014年 | 34篇 |
2013年 | 31篇 |
2012年 | 52篇 |
2011年 | 48篇 |
2010年 | 28篇 |
2009年 | 21篇 |
2008年 | 31篇 |
2007年 | 24篇 |
2006年 | 37篇 |
2005年 | 26篇 |
2004年 | 24篇 |
2003年 | 16篇 |
2002年 | 22篇 |
2001年 | 21篇 |
2000年 | 24篇 |
1999年 | 22篇 |
1998年 | 22篇 |
1997年 | 12篇 |
1996年 | 11篇 |
1995年 | 11篇 |
1994年 | 10篇 |
1993年 | 12篇 |
1992年 | 19篇 |
1991年 | 29篇 |
1990年 | 11篇 |
1989年 | 10篇 |
1988年 | 16篇 |
1987年 | 18篇 |
1986年 | 11篇 |
1985年 | 6篇 |
1984年 | 7篇 |
1983年 | 4篇 |
1982年 | 3篇 |
1981年 | 4篇 |
1980年 | 8篇 |
1979年 | 10篇 |
1978年 | 5篇 |
1977年 | 10篇 |
1976年 | 4篇 |
1975年 | 4篇 |
1974年 | 3篇 |
排序方式: 共有804条查询结果,搜索用时 0 毫秒
801.
802.
Lars Vinter-Jensen Morten Smerup Peter Kissmeyer-Nielsen Steen Seier Poulsen 《Regulatory peptides》1995,60(2-3):117-124
We examined the effects of treatment with human recombinant epidermal growth factor (EGF) on the functioning small intestine in the rat. Male Wistar rats, 7–8 weeks old, were treated with EGF administered subcutaneously in doses of 0 (n = 7) or 150 μg/kg/day (n = 8) for 4 weeks. The histological composition and mucosal surface area of the perfusion-fixed small intestine was quantified with stereological principles. The length of the gut remained unchanged. The amount of tissue and surface area per length of gut (median (ranges)) were increased from 117 (101–131) mg/cm and 2.6 (2.1–3.5) cm2/cm in the controls to 146 (138–152) mg/cm and 3.5 (2.5–3.8) cm2/cm for the complete small intestine (both comparisons p < 0.02). The weight increase was due to mucosal growth in all parts of the intestine, whereas the surface area was only increased in proximal and middle parts. It is concluded that EGF treatment in rats increases the mucosal weight and surface area of the functioning small intestine. 相似文献
803.
804.
G K Mbassa J S Poulsen 《Comparative biochemistry and physiology. B, Comparative biochemistry》1991,100(2):413-422
1. Plasma calcium, magnesium, inorganic phosphorus, sodium and potassium concentrations, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and creatine kinase activities were determined in young and adult non-pregnant non-lactating, early and late non-lactating pregnant and early, mid- and late non-pregnant lactating Danish landrace goats in five herds. The purpose was to determine the influence of pregnancy and lactation on the levels of these parameters and the effect of age and parity on the changes. 2. Calcium, phosphorus, alanine aminotransferase, alkaline phosphatase and aspartate aminotransferase decreased in late gestation. Magnesium and creatine kinase decreased in early lactating goats but increased in subsequent lactation periods. Sodium and potassium fluctuated little during pregnancy and lactation. Calcium, magnesium and potassium profiles were inversely, while phosphorus was directly, proportional to parity. 3. There were significant differences in most ions and enzymes between goats of different herds (within the same physiological state). 4. The transferases and creatine kinase were higher in young goats than in old ones, while alkaline phosphatase was unpredictably high or low in individual goats. 5. Alterations in the level of plasma electrolytes and enzyme activities occur due to pregnancy and lactation and the degree depends on age and parity, influenced also by environment. 相似文献