全文获取类型
收费全文 | 1335篇 |
免费 | 169篇 |
出版年
2022年 | 9篇 |
2021年 | 12篇 |
2020年 | 13篇 |
2018年 | 15篇 |
2017年 | 11篇 |
2016年 | 21篇 |
2015年 | 37篇 |
2014年 | 44篇 |
2013年 | 53篇 |
2012年 | 61篇 |
2011年 | 81篇 |
2010年 | 46篇 |
2009年 | 38篇 |
2008年 | 53篇 |
2007年 | 53篇 |
2006年 | 67篇 |
2005年 | 61篇 |
2004年 | 53篇 |
2003年 | 59篇 |
2002年 | 54篇 |
2001年 | 43篇 |
2000年 | 36篇 |
1999年 | 39篇 |
1998年 | 20篇 |
1997年 | 16篇 |
1996年 | 17篇 |
1995年 | 16篇 |
1994年 | 18篇 |
1993年 | 12篇 |
1992年 | 31篇 |
1991年 | 31篇 |
1990年 | 25篇 |
1989年 | 33篇 |
1988年 | 25篇 |
1987年 | 17篇 |
1986年 | 23篇 |
1985年 | 16篇 |
1984年 | 17篇 |
1983年 | 19篇 |
1982年 | 8篇 |
1981年 | 8篇 |
1980年 | 15篇 |
1979年 | 22篇 |
1978年 | 16篇 |
1977年 | 9篇 |
1976年 | 13篇 |
1974年 | 12篇 |
1973年 | 11篇 |
1972年 | 7篇 |
1970年 | 12篇 |
排序方式: 共有1504条查询结果,搜索用时 15 毫秒
71.
Yuzuru Sanemitsu Norio Kurihara Minoru Nakajima G. E. McCasland L. F. Johnson L. C. Carey 《Bioscience, biotechnology, and biochemistry》2013,77(5):845-857
Two diastereomers of 6-bromo-1, 2, 3, 4, 5-pentachlorocyclohexane were synthesized from the dl (36/45)-diastereomer of 3, 4, 5, 6-tetrachlorocyclohexene (α-BTC) and the dl (346/5)-diastereomer (γ-BTC) by several stepwise routes. Both of these new products were shown to have the configuration of lindane by NMR studies at 300 MHz and by the synthetic routes. Three diastereomers of 6-bromo-3, 4, 5-trichlorocyclohexene were also prepared and the configurations determined partly by means of 300 MHz NMR. 相似文献
72.
73.
Adipose tissue fibrosis,hypertrophy, and hyperplasia: Correlations with diabetes in human obesity
下载免费PDF全文
![点击此处可从《Obesity (Silver Spring, Md.)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Lindsey A. Muir Christopher K. Neeley Kevin A. Meyer Nicki A. Baker Alice M. Brosius Alexandra R. Washabaugh Oliver A. Varban Jonathan F. Finks Brian F. Zamarron Carmen G. Flesher Joshua S. Chang Jennifer B. DelProposto Lynn Geletka Gabriel Martinez‐Santibanez Niko Kaciroti Carey N. Lumeng Robert W. O'Rourke 《Obesity (Silver Spring, Md.)》2016,24(3):597-605
74.
75.
C García-Vielma MI Dávila-Rodríguez F Hernández-Garza RM Cerda-Flores 《Biotechnic & histochemistry》2016,91(2):102-107
We performed a hospital-based, unmatched case-control study to investigate the association between progressive stages of cervical neoplasia and digital analysis of cell proliferation by silver stained nucleolus organizer region associated proteins (AgNORs). We measured cell proliferation levels in the cervical epithelial cells of 10 women with low grade squamous intraepithelial lesions (LG-SIL), eight with high grade squamous intraepithelial lesions (HG-SIL), 11 with cervical cancer (CC) and eight with no cervical lesions (controls) using the AgNORs technique. Cell proliferation was measured by digital image analysis (DIA). DIA revealed increased total areas of AgNORs in HG-SIL and CC compared to LG-SIL and control patients. AgNORs with a kidney or cluster shape exhibited greater areas than those with a spherical or long shape. We propose a cut-off of 118 pixels to differentiate benign (control and LG-SIL) from malignant (HG-SIL and CC) lesions. DIA of AgNORs is a simple and inexpensive method for studying proliferation. The increased total area of AgNORs in malignant lesions provides information regarding cell behavior and may be related to cervical carcinogenesis; however, further validation studies are required to establish its usefulness in cytological analysis. 相似文献
76.
Linda M. Delahanty Thomas A. Wadden Pamela J. Goodwin Catherine M. Alfano Cynthia A. Thomson Melinda L. Irwin Marian L. Neuhouser Tracy E. Crane Elizabeth Frank Patricia A. Spears Bonnie P. Gillis Dawn L. Hershman Electra D. Paskett Judith Hopkins Vanessa Bernstein Vered Stearns Julia White Clifford Hudis Eric P. Winer Lisa A. Carey Ann H. Partridge Jennifer A. Ligibel 《Obesity (Silver Spring, Md.)》2022,30(1):28-38
77.
78.
79.
Alpha-B crystallin gene (CRYAB) mutation causes dominant congenital posterior polar cataract in humans 总被引:10,自引:0,他引:10
下载免费PDF全文
![点击此处可从《American journal of human genetics》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Berry V Francis P Reddy MA Collyer D Vithana E MacKay I Dawson G Carey AH Moore A Bhattacharya SS Quinlan RA 《American journal of human genetics》2001,69(5):1141-1145
Congenital cataracts are an important cause of bilateral visual impairment in infants. In a four-generation family of English descent, we mapped dominant congenital posterior polar cataract to chromosome 11q22-q22.3. The maximum LOD score, 3.92 at recombination fraction 0, was obtained for marker D11S898, near the gene that encodes crystallin alpha-B protein (CRYAB). By sequencing the coding regions of CRYAB, we found in exon 3 a deletion mutation, 450delA, that is associated with cataract in this family. The mutation resulted in a frameshift in codon 150 and produced an aberrant protein consisting of 184 residues. This is the first report of a mutation, in this gene, resulting in isolated congenital cataract. 相似文献
80.
Cross-linking of surface Ig receptors with anti IgM (anti-mu heavy chain, anti-mu), but not anti-IgD (anti-delta heavy chain, anti-delta), Abs leads to growth arrest and apoptosis in several extensively characterized B cell lymphomas. By poorly understood mechanisms, both Igs transiently stimulate c-Myc protein expression. However, ultimately, only anti-mu causes a severe loss in c-Myc and a large induction of p27(Kip1) protein expression. Because phosphatidylinositol 3-kinase (PI3K) has been established as a major modulator of cellular growth and survival, we investigated its role in mediating anti-Ig-stimulated outcomes. Herein, we show that PI3K pathways regulate cell cycle progression and apoptosis in the ECH408 B cell lymphoma. Anti-mu and anti-delta driven c-Myc protein changes precisely follow their effects on the PI3K effector, p70(S6K). Upstream of p70(S6K), signaling through both Ig receptors depresses PI3K pathway phospholipids below control with time, which is followed by p27(Kip1) induction. Conversely, anti-delta, but not anti-mu stimulated PI3K-dependent phospholipid return to control levels by 4-8 h. Abrogation of the PI3K pathway with specific inhibitors mimics anti-mu action, potentiates anti-mu-induced cell death and, importantly, converts anti-delta to a death signal. Transfection with active PI3K kinase construct induces anti-mu resistance, whereas transfection with dominant negative PI3K augments anti-mu sensitivity. Our results show that prolonged disengagement of PI3K or down-regulation of its products by anti-mu (and not anti-delta) determines B cell fate. 相似文献