全文获取类型
收费全文 | 664162篇 |
免费 | 72145篇 |
国内免费 | 330篇 |
专业分类
736637篇 |
出版年
2016年 | 7061篇 |
2015年 | 9309篇 |
2014年 | 11152篇 |
2013年 | 16318篇 |
2012年 | 17890篇 |
2011年 | 18489篇 |
2010年 | 12429篇 |
2009年 | 11668篇 |
2008年 | 16607篇 |
2007年 | 17354篇 |
2006年 | 16578篇 |
2005年 | 15903篇 |
2004年 | 15805篇 |
2003年 | 15466篇 |
2002年 | 15187篇 |
2001年 | 31369篇 |
2000年 | 31716篇 |
1999年 | 24940篇 |
1998年 | 8193篇 |
1997年 | 8687篇 |
1996年 | 8180篇 |
1995年 | 7594篇 |
1994年 | 7473篇 |
1993年 | 7553篇 |
1992年 | 20909篇 |
1991年 | 20614篇 |
1990年 | 20121篇 |
1989年 | 19818篇 |
1988年 | 18565篇 |
1987年 | 17457篇 |
1986年 | 16075篇 |
1985年 | 16382篇 |
1984年 | 13261篇 |
1983年 | 11460篇 |
1982年 | 8588篇 |
1981年 | 7682篇 |
1980年 | 7230篇 |
1979年 | 12550篇 |
1978年 | 9787篇 |
1977年 | 9145篇 |
1976年 | 8474篇 |
1975年 | 9330篇 |
1974年 | 10054篇 |
1973年 | 9910篇 |
1972年 | 9067篇 |
1971年 | 8290篇 |
1970年 | 7184篇 |
1969年 | 7124篇 |
1968年 | 6533篇 |
1967年 | 5619篇 |
排序方式: 共有10000条查询结果,搜索用时 10 毫秒
51.
52.
Trigger finger is a relatively common clinical entity, most frequently caused by stenosing tenosynovitis. Several other conditions not related to tenosynovitis also have been described as a cause of triggering, and these have been reviewed. We present a rare anomaly of the fourth lumbrical muscle insertion as a cause of triggering of the right little finger. This was completely relieved following excision of the anomalous muscle. This rare anatomic variant should be added to the list of potential causes of trigger finger. 相似文献
53.
54.
55.
56.
57.
58.
SSU1 encodes a plasma membrane protein with a central role in a network of proteins conferring sulfite tolerance in Saccharomyces cerevisiae. 下载免费PDF全文
The Saccharomyces cerevisiae SSU1 gene was isolated based on its ability to complement a mutation causing sensitivity to sulfite, a methionine intermediate. SSU1 encodes a deduced protein of 458 amino acids containing 9 or 10 membrane-spanning domains but has no significant similarity to other proteins in public databases. An Ssu1p-GEP fusion protein was localized to the plasma membrane. Multicopy suppression analysis, undertaken to explore relationships among genes previously implicated in sulfite metabolism, suggests a regulatory pathway in which SSU1 acts downstream of FZF1 and SSU3, which in turn act downstream of GRR1. 相似文献
59.
60.
The frequency of cytokine-producing CD4-/CD8- mononuclear cells was assessed in patients of different age groups (29 infants, aged 1-5 years; 30 schoolchildren, aged 6-14 years, 26 adults, aged > 15 years) with acute Plasmodium falciparum malaria, from Gabon. Fifteen patients were followed up before antimalarial treatment (day 0), during parasite clearance (day 3) and after resolution of parasitemia (day 10). By using flow cytometry for intracellular detection of cytokines, a striking expansion of CD4-/CD8- cells producing the type 1 cytokines interleukin (IL)-2-/interferon (IFN)-gamma+, IL-2+/IFN-gamma+ and IL-2+/IFN-gamma- was observed in adults as compared with children. Type 2 cytokine expression (IL-4+/IFN-gamma-, IL-13+/IFN-gamma-) and type 0 cells (IL-4+/IFN-gamma+, IL-13+/IFN-gamma+) were not significantly different between the three age groups. Patients with severe malaria had a significantly increased frequency of type 2 cytokine-producing CD4-/CD8- cells. Drug-induced clearance of parasitemia was characterized by a decrease of IL-2+/IFN-gamma- and type 2 cytokine expressing CD4-/CD8- cells and by a gradual increase of IL-10+/IFN-gamma- expression. The type 1/type 2 dichotomy observed within the CD4-/CD8- cell population is likely to be of significance in the host response against P. falciparum malaria. 相似文献