全文获取类型
收费全文 | 7116篇 |
免费 | 713篇 |
国内免费 | 1篇 |
出版年
2021年 | 67篇 |
2020年 | 58篇 |
2019年 | 54篇 |
2018年 | 67篇 |
2017年 | 65篇 |
2016年 | 117篇 |
2015年 | 194篇 |
2014年 | 230篇 |
2013年 | 285篇 |
2012年 | 434篇 |
2011年 | 393篇 |
2010年 | 237篇 |
2009年 | 215篇 |
2008年 | 335篇 |
2007年 | 408篇 |
2006年 | 325篇 |
2005年 | 350篇 |
2004年 | 342篇 |
2003年 | 289篇 |
2002年 | 310篇 |
2001年 | 144篇 |
2000年 | 139篇 |
1999年 | 132篇 |
1998年 | 89篇 |
1997年 | 60篇 |
1996年 | 59篇 |
1995年 | 64篇 |
1994年 | 73篇 |
1993年 | 73篇 |
1992年 | 121篇 |
1991年 | 101篇 |
1990年 | 115篇 |
1989年 | 85篇 |
1988年 | 92篇 |
1987年 | 100篇 |
1986年 | 85篇 |
1985年 | 97篇 |
1984年 | 83篇 |
1983年 | 90篇 |
1982年 | 76篇 |
1981年 | 78篇 |
1980年 | 65篇 |
1979年 | 102篇 |
1978年 | 93篇 |
1977年 | 71篇 |
1976年 | 67篇 |
1975年 | 57篇 |
1974年 | 66篇 |
1973年 | 58篇 |
1972年 | 65篇 |
排序方式: 共有7830条查询结果,搜索用时 109 毫秒
1.
D J Cruickshank P B Terry W T Fullerton 《The International journal of biological markers》1991,6(4):247-252
Seventy four consecutive patients with epithelial ovarian cancer have been followed up longitudinally with serial serum CA125 for up to 48 months. From this database, the CA125 changes in small volume disease have been evaluated. For long term complete responders (n = 12), the mean plateau level of CA125 was 7.2 U/ml (95% confidence interval; 5.6 to 9.2 U/ml). The natural half-life of CA125 at 5.1 days (range 3.8 to 7 days) was calculated from five patients with Stage I and II disease who underwent complete surgical excision. A mean lead time of 99 days (range 14 to 255 days) was demonstrated between marker detection of disease progression and clinically apparent progressive disease in 12 out of 13 patients (92%) who relapsed after chemotherapy induced complete remission. The threshold of tumour volume detection with CA125 is unlikely to be determined by an arbitrary cut-off level. The kinetics of CA125 provide more useful information and the potential to define complete response or indeed cure with CA125 parameters requires further investigation. 相似文献
2.
3.
Fructose transporter in human spermatozoa and small intestine is GLUT5. 总被引:15,自引:0,他引:15
C F Burant J Takeda E Brot-Laroche G I Bell N O Davidson 《The Journal of biological chemistry》1992,267(21):14523-14526
We recently reported that the glucose transporter isoform, GLUT5, is expressed on the brush border membrane of human small intestinal enterocytes (Davidson, N. O., Hausman, A. M. L., Ifkovits, C. A., Buse, J. B., Gould, G. W., Burant, C. F., and Bell, G. I. (1992) Am. J. Physiol. 262, C795-C800). To define its role in sugar transport, human GLUT5 was expressed in Xenopus oocytes and its substrate specificity and kinetic properties determined. GLUT5 exhibits selectivity for fructose transport, as determined by inhibition studies, with a Km of 6 mM. In addition, fructose transport by GLUT5 is not inhibited by cytochalasin B, a competitive inhibitor of facilitative glucose transporters. RNA and protein blotting studies showed the presence of high levels of GLUT5 mRNA and protein in human testis and spermatozoa, and immunocytochemical studies localize GLUT5 to the plasma membrane of mature spermatids and spermatozoa. The biochemical properties and tissue distribution of GLUT5 are consistent with a physiological role for this protein as a fructose transporter. 相似文献
4.
5.
Emily Olfson Catherine E. Cottrell Nicholas O. Davidson Christina A. Gurnett Jonathan W. Heusel Nathan O. Stitziel Li-Shiun Chen Sarah Hartz Rakesh Nagarajan Nancy L. Saccone Laura J. Bierut 《PloS one》2015,10(9)
The American College of Medical Genetics and Genomics (ACMG) recommends that clinical sequencing laboratories return secondary findings in 56 genes associated with medically actionable conditions. Our goal was to apply a systematic, stringent approach consistent with clinical standards to estimate the prevalence of pathogenic variants associated with such conditions using a diverse sequencing reference sample. Candidate variants in the 56 ACMG genes were selected from Phase 1 of the 1000 Genomes dataset, which contains sequencing information on 1,092 unrelated individuals from across the world. These variants were filtered using the Human Gene Mutation Database (HGMD) Professional version and defined parameters, appraised through literature review, and examined by a clinical laboratory specialist and expert physician. Over 70,000 genetic variants were extracted from the 56 genes, and filtering identified 237 variants annotated as disease causing by HGMD Professional. Literature review and expert evaluation determined that 7 of these variants were pathogenic or likely pathogenic. Furthermore, 5 additional truncating variants not listed as disease causing in HGMD Professional were identified as likely pathogenic. These 12 secondary findings are associated with diseases that could inform medical follow-up, including cancer predisposition syndromes, cardiac conditions, and familial hypercholesterolemia. The majority of the identified medically actionable findings were in individuals from the European (5/379) and Americas (4/181) ancestry groups, with fewer findings in Asian (2/286) and African (1/246) ancestry groups. Our results suggest that medically relevant secondary findings can be identified in approximately 1% (12/1092) of individuals in a diverse reference sample. As clinical sequencing laboratories continue to implement the ACMG recommendations, our results highlight that at least a small number of potentially important secondary findings can be selected for return. Our results also confirm that understudied populations will not reap proportionate benefits of genomic medicine, highlighting the need for continued research efforts on genetic diseases in these populations. 相似文献
6.
7.
William J. Sames Terry A. Klein Heung Chul Kim Sung Tae Chong In Yong Lee Se Hun Gu Yon Mi Park Ji Hye Jeong Jin‐Won Song 《Journal of vector ecology》2009,34(2):225-231
The Twin Bridges Training Area (TBTA) in the Republic of Korea consists of dirt roads, barren training areas, and forested hillsides adjacent to linear and broad expanses of tall grasses, herbaceous, and scrub vegetation. Of the six species of small mammals, the striped field mouse, Apodemus agrarius, was the most frequently captured (96.1%). Apodemus agrarius capture rates varied from 17.7 to 33.2% during three trapping periods. Gravid females were observed during November‐December 2006 (8.4%) and March 2007 (5.1%). In 2005, the overall seroprevalence of Hantaan virus (HTNV) was high (34.4%) and lower during surveys in 2006 (14.2%) and 2007 (13.8%). Seroprevalence was directly correlated with weight increase of A. agrarius. 相似文献
8.
9.
10.
Richard Terry 《BMJ (Clinical research ed.)》1952,1(4773):1407-1408