全文获取类型
收费全文 | 444篇 |
免费 | 34篇 |
国内免费 | 3篇 |
出版年
2017年 | 5篇 |
2016年 | 3篇 |
2015年 | 4篇 |
2014年 | 13篇 |
2013年 | 22篇 |
2012年 | 15篇 |
2011年 | 18篇 |
2010年 | 10篇 |
2009年 | 7篇 |
2008年 | 12篇 |
2007年 | 12篇 |
2006年 | 12篇 |
2005年 | 11篇 |
2004年 | 6篇 |
2003年 | 17篇 |
2002年 | 8篇 |
2001年 | 12篇 |
2000年 | 10篇 |
1999年 | 12篇 |
1998年 | 5篇 |
1997年 | 8篇 |
1996年 | 6篇 |
1995年 | 5篇 |
1994年 | 3篇 |
1992年 | 5篇 |
1990年 | 6篇 |
1989年 | 11篇 |
1988年 | 12篇 |
1987年 | 8篇 |
1986年 | 18篇 |
1985年 | 10篇 |
1984年 | 12篇 |
1983年 | 4篇 |
1982年 | 3篇 |
1981年 | 11篇 |
1980年 | 12篇 |
1979年 | 17篇 |
1978年 | 6篇 |
1977年 | 13篇 |
1976年 | 13篇 |
1975年 | 10篇 |
1974年 | 4篇 |
1972年 | 6篇 |
1971年 | 6篇 |
1969年 | 3篇 |
1968年 | 4篇 |
1967年 | 3篇 |
1965年 | 3篇 |
1940年 | 6篇 |
1938年 | 3篇 |
排序方式: 共有481条查询结果,搜索用时 15 毫秒
61.
62.
Low-molecular-weight Ia antigens can be detected in mouse serum. A procedure for isolating these antigens from serum in high yield is described. The Ia antigen preparation was found to be rich in carbohydrate, low in protein, and strongly bound to Concanavalin A andLotus lectins. Furthermore, the Ia antigenicity was destroyed by periodate oxidation and neuraminidase treatment, but was unaffected by pronase. These observations strongly suggest that the Ia antigens in serum are oligosaccharide in nature. Such a conclusion implies that at least some of the genes in theI region of theH-2 gene complex code for glycosyl transferase enzymes. 相似文献
63.
64.
65.
66.
67.
G Mazoujian T H Parish D E Haagensen 《The journal of histochemistry and cytochemistry》1988,36(4):377-382
Five monoclonal antibodies (Mabs) raised against separate determinants on a breast gross cystic disease fluid protein of 15 KD (GCDFP-15) were compared to one another and to a rabbit antiserum (Rb) against GCDFP-15 by radioimmunoassay (RIA) and by immunoperoxidase localization in paraffin-embedded tissues. All five Mabs and the Rb were equivalent in recognition of GCDFP-15 in solution, as determined by RIA. However, two of the Mabs (A5, B15) showed only minimal binding to GCDFP-15 in paraffin-embedded tissues, whereas the other three Mabs (B1, B4, D6) were equivalent to the Rb in staining intensity. These latter three Mabs and the Rb were evaluated by the immunoperoxidase technique on a variety of benign and malignant neoplasms as well as normal tissues (150 specimens) for staining specificity. Immunoperoxidase staining by the three Mabs vs the Rb was equivalent in apocrine glands, metaplastic apocrine epithelium of breast, and breast carcinomas with apocrine features. No staining of the Mabs or Rb was seen in the other tissue specimens. 相似文献
68.
Phagocytic Cells in the Peripheral Blood of the Dogfish Scyliorhinus canicula L. I. In Vitro Studies
In vitro phagocytosis by peripheral blood leucocytes of the dogfish Scyliorhinus canicula L. was examined by exposing adherent cells to a variety of particulate and soluble antigens and inert material. Their subsequent uptake was monitored by light, scanning and transmission electron microscopy. The monocyte and the neutrophil-like granulocyte were found to be the major phagocytic cells. Larger particles like yeasts and erythrocytes were the most avidly phagocytosed. From studies on the effects of pH, temperature and the presence of plasma, metabolic inhibitors and divalent ions, it appeared that optimum phagocytosis occurred at pH 7.0 and between 10 and 20°C. Serum factors did not enhance the process in this species. Finally, the in vitro clearance of 5 bacterial species indicated that the presence of blood phagocytes had little or no effect on bacterial numbers. 相似文献
69.
Robert Clarke Peng Xu Derrick Bennett Sarah Lewington Krina Zondervan Sarah Parish Alison Palmer Sarah Clark Lon Cardon Richard Peto Mark Lathrop Rory Collins 《PLoS genetics》2006,2(7)
Lymphotoxin-α (LTA) is a pro-inflammatory cytokine that plays an important role in the immune system and local inflammatory response. LTA is expressed in atherosclerotic plaques and has been implicated in the pathogenesis of atherosclerosis and coronary heart disease (CHD). Polymorphisms in the gene encoding lymphotoxin-α (LTA) on Chromosome 6p21 have been associated with susceptibility to CHD, but results in different studies appear to be conflicting. We examined the association of seven single nucleotide polymorphisms (SNPs) across the LTA gene, and their related haplotypes, with risk of myocardial infarction (MI) in the International Study of Infarct Survival (ISIS) case-control study involving 6,928 non-fatal MI cases and 2,712 unrelated controls. The seven SNPs (including the rs909253 and rs1041981 SNPs previously implicated in the risk of CHD) were in strong linkage disequilibrium with each other and contributed to six common haplotypes. Some of the haplotypes for LTA were associated with higher plasma concentrations of C-reactive protein (p = 0.004) and lower concentrations of albumin (p = 0.023). However, none of the SNPs or related haplotypes were significantly associated with risk of MI. The results of the ISIS study were considered in the context of six previously published studies that had assessed this association, and this meta-analysis found no significant association with CHD risk using a recessive model and only a modest association using a dominant model (with narrow confidence intervals around these risk estimates). Overall, these studies provide reliable evidence that these common polymorphisms for the LTA gene are not strongly associated with susceptibility to coronary disease. 相似文献
70.
The ability of different classes of passively administered guinea pig antibody (γ1, γ2, and IgM) to regulate humoral and cell-mediated immunity to flagellin, polymerized flagellin (POL), and sheep red blood cells (SRBC) was investigated in rats. It was found that at high concentrations, all classes of antibody suppressed the primary antibody responses and usually enhanced the delayed-type hypersensitivity induced by the three antigens. With flagellin and SRBC, the different classes of passive antibody varied in their suppressing and enhancing properties, being in the order: γ2 > γ1 = IgM. At low concentrations, γ1 and IgM enhanced the primary antibody response and suppressed the delayed hypersensitivity induced by flagellin. Such an effect was not observed with either POL or SRBC. Priming for a secondary antibody response was less readily suppressed by all classes of passive antibody. The removal of macrophage cytophilic antibody from γ2 converted this antibody to a preparation (γ2 absorbed) which had effects on humoral and cell-mediated immunity approaching that of γ1 antibody. 相似文献