全文获取类型
收费全文 | 1732篇 |
免费 | 91篇 |
国内免费 | 33篇 |
学科分类
医药卫生 | 1856篇 |
出版年
2021年 | 18篇 |
2019年 | 16篇 |
2018年 | 25篇 |
2017年 | 22篇 |
2016年 | 27篇 |
2015年 | 29篇 |
2014年 | 36篇 |
2013年 | 84篇 |
2012年 | 36篇 |
2011年 | 43篇 |
2010年 | 66篇 |
2009年 | 66篇 |
2008年 | 32篇 |
2007年 | 60篇 |
2006年 | 39篇 |
2005年 | 41篇 |
2004年 | 29篇 |
2003年 | 27篇 |
2002年 | 36篇 |
2001年 | 36篇 |
2000年 | 25篇 |
1999年 | 37篇 |
1998年 | 88篇 |
1997年 | 75篇 |
1996年 | 78篇 |
1995年 | 52篇 |
1994年 | 63篇 |
1993年 | 51篇 |
1992年 | 17篇 |
1991年 | 24篇 |
1990年 | 31篇 |
1989年 | 44篇 |
1988年 | 53篇 |
1987年 | 38篇 |
1986年 | 34篇 |
1985年 | 30篇 |
1984年 | 31篇 |
1983年 | 19篇 |
1982年 | 26篇 |
1981年 | 20篇 |
1980年 | 17篇 |
1979年 | 21篇 |
1978年 | 18篇 |
1977年 | 23篇 |
1976年 | 18篇 |
1975年 | 19篇 |
1974年 | 13篇 |
1973年 | 14篇 |
1972年 | 11篇 |
1971年 | 11篇 |
排序方式: 共有1856条查询结果,搜索用时 15 毫秒
11.
12.
13.
14.
Rupture of an intra-aortic balloon counterpulsator (IABCP) demands immediate removal. We report a case of thrombus formation within a Datascope IABCP secondary to IABCP rupture, necessitating surgical exploration for removal. There is a disturbing pattern of balloon ruptures with this type of IABCP. 相似文献
15.
16.
17.
Verschuren MC; Blom B; Bogers AJ; Spits H; van Dongen JJ 《International immunology》1998,10(12):1873-1880
Recombination of deltaRec to psiJalpha will delete the TCR delta gene,
which is thought to play an important role in the bifurcation of the TCR
alphabeta versus TCR gammadelta differentiation lineages. We recently
detected a DNA-binding protein in human thymocytes, the so- called PJA-BP,
which recognizes the psiJalpha gene segment and might be one of the factors
involved in the regulation of preferential deltaRec- psiJalpha
rearrangements. We now investigate PJA-BP expression and its correlation
with TCR delta gene deletion in thymocytes. Our electrophoretic mobility
shift assay experiments showed that the PJA-BP is evolutionary conserved in
human, murine and simian thymocytes. Using a large series of human
hematopoietic malignancies (n = 30), we conclude that PJA-BP expression is
thymocyte specific and seems to be restricted to thymocytes committed to
the TCR alphabeta lineage. Analysis of seven well-defined human thymocyte
subpopulations showed that preferential deltaRec-psiJalpha rearrangements
as well as PJA-BP expression can be detected from the immature
CD34-/CD1+/CD3- /CD4+/CD8alpha+beta- thymocyte differentiation stage
onwards. These experiments indicate that expression of PJA-BP in human
thymocytes starts simultaneously with preferential deltaRec-psiJalpha
rearrangements, which supports our hypothesis that PJA-BP is one of the
factors involved in the preferential recombination of deltaRec to
psiJalpha.
相似文献
18.
Circulating antibodies to peripheral nerve in American trypanosomiasis (Chagas' disease). 总被引:12,自引:4,他引:12 下载免费PDF全文
E L Khoury V Ritacco P M Cossio R P Laguens A Szarfman C Diez R M Arana 《Clinical and experimental immunology》1979,36(1):8-15
An antibody reacting with Schwann sheaths of myelinated somatic and unmyelinated autonomic peripheral nerve was found in sixty-one out of seventy-one chronic, and nine out of ten acute, Chagas' disease sera. Indirect immunofluorescence (IFL) was carried out on rat, mouse and human somatic nerves and rat sympathetic nerves with initial serum dilutions of 1 : 10, and the staining reached a final titre of 1 : 320 in some cases. The antibodies fixed complement and were absorbed out by lyophilized epimastigotes of T. cruzi. Lipid extraction of the tissue sections enhanced the staining of myelinated nerve, whereas unfixed unmyelinated sympathetic nerve was strongly reactive. Central nervous tissue did not display any positive staining on neurons, glial cells or periaxonal sheaths. Furthermore, by using a double-labelled IFL technique, it was possible to show that a rabbit antiserum raised against guinea-pig spinal cord and the chagasic anti-nerve antibodies reacted with different structures in the rat sciatic nerve. These findings suggest that the reactive antigen(s) could be located on Schwann cells. The majority, but not all, of the chagasic individuals with anti-nerve antibodies also showed the sarcolemmal and endothelial staining (EVI) previously described in Chagas' disease. The possible recognition of Schwann cell antigens by circulating antibodies in Chagas' disease could be relevant, since an autonomic denervation has been postulated as a pathogenic mechanism of cardiomyopathy and megaviscera in this condition. 相似文献
19.
20.
Missense mutation in a von Willebrand factor type A domain of the alpha 3(VI) collagen gene (COL6A3) in a family with Bethlem myopathy 总被引:2,自引:0,他引:2
Pan TC; Zhang RZ; Pericak-Vance MA; Tandan R; Fries T; Stajich JM; Viles K; Vance JM; Chu ML; Speer MC 《Human molecular genetics》1998,7(5):807-812
The Bethlem myopathy is a rare autosomal dominant proximal myopathy
characterized by early childhood onset and joint contractures. Evidence for
linkage and genetic heterogeneity has been established, with the majority
of families linked to 21q22.3 and one large family linked to 2q37,
implicating the three type VI collagen subunit genes, COL6A1 (chromosome
21), COL6A2 (chromosome 21) and COL6A3 (chromosome 2) as candidate genes.
Mutations of the invariant glycine residues in the triple-helical
domain-coding region of COL6A1 and COL6A2 have been reported previously in
the chromosome 21-linked families. We report here the identification of a
G-->A mutation in the N-terminal globular domain-coding region of COL6A3
in a large American pedigree (19 affected, 12 unaffected), leading to the
substitution of glycine by glutamic acid in the N2 motif, which is
homologous to the type A domains of the von Willebrand factor. This
mutation segregated to all affected family members, to no unaffected family
members, and was not identified in 338 unrelated Caucasian control
chromosomes. Thus mutations in either the triple-helical domain or the
globular domain of type VI collagen appear to cause Bethlem myopathy.
相似文献