全文获取类型
收费全文 | 1830篇 |
免费 | 153篇 |
国内免费 | 1篇 |
专业分类
1984篇 |
出版年
2024年 | 2篇 |
2023年 | 10篇 |
2022年 | 33篇 |
2021年 | 63篇 |
2020年 | 28篇 |
2019年 | 34篇 |
2018年 | 65篇 |
2017年 | 34篇 |
2016年 | 55篇 |
2015年 | 109篇 |
2014年 | 127篇 |
2013年 | 140篇 |
2012年 | 167篇 |
2011年 | 146篇 |
2010年 | 93篇 |
2009年 | 70篇 |
2008年 | 105篇 |
2007年 | 80篇 |
2006年 | 93篇 |
2005年 | 90篇 |
2004年 | 88篇 |
2003年 | 87篇 |
2002年 | 87篇 |
2001年 | 11篇 |
2000年 | 6篇 |
1999年 | 15篇 |
1998年 | 11篇 |
1997年 | 6篇 |
1996年 | 11篇 |
1995年 | 11篇 |
1994年 | 7篇 |
1993年 | 7篇 |
1992年 | 4篇 |
1991年 | 7篇 |
1990年 | 8篇 |
1989年 | 8篇 |
1988年 | 4篇 |
1987年 | 5篇 |
1986年 | 8篇 |
1985年 | 3篇 |
1984年 | 4篇 |
1983年 | 4篇 |
1982年 | 7篇 |
1981年 | 6篇 |
1980年 | 4篇 |
1979年 | 3篇 |
1978年 | 3篇 |
1975年 | 4篇 |
1972年 | 4篇 |
1971年 | 2篇 |
排序方式: 共有1984条查询结果,搜索用时 8 毫秒
31.
32.
A trypsin and chymotrypsin inhibitor was partially purified from Bauhenia purpurea seeds and separated from a second inhibitor by Ecteola cellulose chromatography. The factor inhibited bovine trypsin and chymotrypsin as well as pronase trypsin and elastase. It formed a complex with trypsin and with chymotrypsin, but a ternary complex could not be detected. Differences were detected in the effect on trypsin and on chymotrypsin, although one enzyme interfered with the inhibition of the other. The results obtained point to two active centers on the inhibitor for the trypsin and chymotrypsin inhibition such that the one cannot complex with the inhibitor after this inhibitor had complexed with the other. 相似文献
33.
The ability of the carcinogen, N-acetoxy-2-acetylaminofluorene (N-AcO-AAF), to induce mutations to azaguanine resistance in diploid human cells was quantitatively investigated and shown to be dose-dependent. The 8-azaguanine (AG) resistance was shown to be heritable in the absence of mutagen or selective agent and the cells of the mutant clones were shown to retain normal sensitivity to N-AcO-AAF. 相似文献
34.
35.
James V. McCann Steven R. Bischoff Yu Zhang Dale O. Cowley Veronica Sanchez‐Gonzalez George D. Daaboul Andrew C. Dudley 《Genesis (New York, N.Y. : 2000)》2020,58(7)
Extracellular vesicles (EVs) are abundant, lipid‐enclosed vectors that contain nucleic acids and proteins, they can be secreted from donor cells and freely circulate, and they can be engulfed by recipient cells thus enabling systemic communication between heterotypic cell types. However, genetic tools for labeling, isolating, and auditing cell type‐specific EVs in vivo, without prior in vitro manipulation, are lacking. We have used CRISPR‐Cas9‐mediated genome editing to generate mice bearing a CD63‐emGFPloxP/stop/loxP knock‐in cassette that enables the specific labeling of circulating CD63+ vesicles from any cell type when crossed with lineage‐specific Cre recombinase driver mice. As proof‐of‐principle, we have crossed these mice with Cdh5‐CreERT2 mice to generate CD63emGFP+ vasculature. Using these mice, we show that developing vasculature is marked with emerald GFP (emGFP) following tamoxifen administration to pregnant females. In adult mice, quiescent vasculature and angiogenic vasculature (in tumors) is also marked with emGFP. Moreover, whole plasma‐purified EVs contain a subpopulation of emGFP+ vesicles that are derived from the endothelium, co‐express additional EV (e.g., CD9 and CD81) and endothelial cell (e.g., CD105) markers, and they harbor specific miRNAs (e.g., miR‐126, miR‐30c, and miR‐125b). This new mouse strain should be a useful genetic tool for generating cell type‐specific, CD63+ EVs that freely circulate in serum and can subsequently be isolated and characterized using standard methodologies. 相似文献
36.
Kopruszinski Caroline M. Swiokla Juliana Lee Yeon Sun Navratilova Edita VanderVeen Laurie Yang Miao Liu Yi Miyazaki Takahiro Schmidt William K. Zalevsky Jonathan Porreca Frank 《Cellular and molecular neurobiology》2021,41(5):949-960
Cellular and Molecular Neurobiology - Pharmacological evaluation of the mu-opioid receptor (MOR) agonist properties of NKTR-181 in rodent models. Graded noxious stimulus intensities were used in... 相似文献
37.
Erukainure Ochuko L. Salau Veronica F. Atolani Olubunmi Ravichandran Rahul Banerjee Priyanka Preissner Robert Koorbanally Neil A. Islam Md. Shahidul 《Amino acids》2021,53(7):1135-1151
Amino Acids - The antidiabetic effect of l-leucine has been attributed to its modulatory effect on glucose uptake and lipid metabolism in muscles. However, there is a dearth on its effect on... 相似文献
38.
Anaya-Ramos Laura Díaz-Ruíz Araceli Ríos Camilo Mendez-Armenta Marisela Montes Sergio Aguirre-Vidal Yoshajandith García-Jiménez Sara Baron-Flores Veronica Monroy-Noyola Antonio 《Biometals》2021,34(6):1295-1311
BioMetals - Thallium (TI) is one of the most toxic heavy metals. Human exposure to Tl occurs through contaminated drinking water and from there to food, a threat to health. Recently, environmental... 相似文献
39.
Maglieri Veronica Riccobono Marco Germain Giunchi Dimitri Palagi Elisabetta 《Journal of Ethology》2021,39(3):287-296
Journal of Ethology - By gathering data on people during their ordinary daily activities, we tested if looking at, but not manipulating, smartphones led to a mimicry response in the observer.... 相似文献
40.
Fais Giacomo Malavasi Veronica Scano Paola Soru Santina Caboni Pierluigi Cao Giacomo 《Extremophiles : life under extreme conditions》2021,25(4):357-368
Extremophiles - With an unsupervised GC–MS metabolomics approach, polar metabolite changes of the microalgae Coccomyxa melkonianii SCCA 048 grown under standard conditions for seven weeks... 相似文献