全文获取类型
收费全文 | 1912篇 |
免费 | 257篇 |
出版年
2021年 | 24篇 |
2016年 | 25篇 |
2015年 | 41篇 |
2014年 | 33篇 |
2013年 | 54篇 |
2012年 | 72篇 |
2011年 | 77篇 |
2010年 | 36篇 |
2009年 | 43篇 |
2008年 | 59篇 |
2007年 | 61篇 |
2006年 | 65篇 |
2005年 | 62篇 |
2004年 | 76篇 |
2003年 | 52篇 |
2002年 | 54篇 |
2001年 | 64篇 |
2000年 | 65篇 |
1999年 | 50篇 |
1998年 | 32篇 |
1997年 | 22篇 |
1996年 | 26篇 |
1995年 | 31篇 |
1994年 | 19篇 |
1993年 | 30篇 |
1992年 | 40篇 |
1991年 | 36篇 |
1990年 | 56篇 |
1989年 | 54篇 |
1988年 | 55篇 |
1987年 | 50篇 |
1986年 | 48篇 |
1985年 | 52篇 |
1984年 | 37篇 |
1983年 | 29篇 |
1982年 | 31篇 |
1981年 | 34篇 |
1980年 | 26篇 |
1979年 | 31篇 |
1978年 | 25篇 |
1977年 | 28篇 |
1976年 | 34篇 |
1975年 | 32篇 |
1974年 | 30篇 |
1973年 | 33篇 |
1972年 | 25篇 |
1971年 | 21篇 |
1970年 | 20篇 |
1969年 | 16篇 |
1968年 | 18篇 |
排序方式: 共有2169条查询结果,搜索用时 187 毫秒
1.
Summary The degree of satellite association was found to be significantly higher in phytohemagglutinin (PHA)-stimulated lymphocytes from cystic fibrosis (CF) patients than from those of control individuals. PHA-stimulated lymphocytes from obligatory heterozygotes for the CF mutant allele showed an intermediate degree of satellite association. The degree of satellite association was estimated by the frequency of cells exhibiting associations, by the number of associations per cell, and by the number of chromosomes in an association. The differences in the degree of satellite association were dependent on the concentration of colchicine used for cell arrest. These findings may assist in developing a diagnostic method for the early identification of heterozygotes for the CF allele and for prenatal detection of CF homozygous fetuses.This paper is based on a portion of a dissertation to be submitted by Y. Ravia in partial fulfilment of the Ph. D. requirements in the Graduate School of Tel Aviv University 相似文献
2.
3.
4.
5.
6.
7.
8.
9.
1,25-Dihydroxyvitamin D3 and the regulation of the differentiation and function of macrophages and granulocytes 总被引:1,自引:0,他引:1
1,25-Dihydroxyvitamin D3 (1,25(OH)2D3) exerts a differential inhibitory effect on the formation of granulocyte, granulocyte/macrophage, and macrophage colonies grown from mouse bone marrow precursor cells; 50% inhibition was attained at 1.1, 2.3, and 23 nM 1,25(OH)2D3, respectively. The inhibition of colony formation, as well as phagocyte proliferation in liquid cultures, requires the presence of 1,25(OH)2D3 in the early stages of culture (up to 72 h after culture initiation). 1,25(OH)2D3 induces a dose- and time-dependent augmentation of the phagocytic capability of mononuclear phagocytes (up to 100%) towards both heat-killed yeast cells and IgG-coated sheep red blood cells. The augmentation of the phagocytic capability of the mononuclear phagocytes depends critically on when 1,25(OH)2D3 is added. It is effective when added up to 72 h after culture initiation, while at later stages (greater than or equal to 96 h) the cells are no longer induced to express enhanced phagocytic capability. We suggest that these phenomena may be relevant to hemopoietic processes. 相似文献
10.
Summary The child with iminoglycinuria is in our observation. Hyperprolinuria was seen at 5 months by screening program. The child was repeatedly examined in the hospital and was seen last time at 16 months. IQ was 67, in the urine were excessive amounts of glycine, proline a hydroxyproline. In the blood aminoacids were in normal levels. In the child was noticed the same increase of proline in the blood as in the control child of the same age following loading test with L-proline, indicating normal intestinal absoption. Both parents and father's sister's 2-year-old mentally retarded child exhibit excessive glycinuria. The father, his sister, father's father, and grandfather are partialy, congenitaly deaf. 相似文献