全文获取类型
收费全文 | 3584篇 |
免费 | 295篇 |
国内免费 | 108篇 |
出版年
2023年 | 20篇 |
2022年 | 53篇 |
2021年 | 151篇 |
2020年 | 92篇 |
2019年 | 133篇 |
2018年 | 142篇 |
2017年 | 101篇 |
2016年 | 118篇 |
2015年 | 186篇 |
2014年 | 212篇 |
2013年 | 260篇 |
2012年 | 296篇 |
2011年 | 222篇 |
2010年 | 172篇 |
2009年 | 125篇 |
2008年 | 164篇 |
2007年 | 135篇 |
2006年 | 143篇 |
2005年 | 131篇 |
2004年 | 124篇 |
2003年 | 134篇 |
2002年 | 105篇 |
2001年 | 100篇 |
2000年 | 88篇 |
1999年 | 76篇 |
1998年 | 45篇 |
1997年 | 31篇 |
1996年 | 29篇 |
1995年 | 30篇 |
1994年 | 17篇 |
1993年 | 14篇 |
1992年 | 25篇 |
1991年 | 21篇 |
1990年 | 21篇 |
1989年 | 26篇 |
1988年 | 17篇 |
1987年 | 16篇 |
1985年 | 20篇 |
1984年 | 13篇 |
1983年 | 12篇 |
1982年 | 11篇 |
1979年 | 13篇 |
1977年 | 10篇 |
1976年 | 10篇 |
1975年 | 9篇 |
1974年 | 9篇 |
1973年 | 9篇 |
1972年 | 13篇 |
1971年 | 11篇 |
1967年 | 9篇 |
排序方式: 共有3987条查询结果,搜索用时 625 毫秒
101.
102.
Three, six, nine, and twelve V of electric pulse (EP) was applied to a culture of Weissella cibaria SKkimchi1 in MRS medium and kimchi-making culture (KMC). Viable cell number of SKkimchi1 in MRS medium was decreased in proportion to pulse intensity but that of bacteria in KMC was not. Lactic acid and ethanol produced by SKkimchi1 tended to be decreased in proportion to EP intensity but acetic acid was proportionally increased to EP intensity. Lactic acid, ethanol, and propionic acid produced in KMC were proportionally decreased, but acetic acid was proportionally increased to the EP intensity. Bacterial community and diversity in KMC were analyzed based on culture time by a temperature gradient gel electrophoresis (TGGE) technique. Most bacterial communities grown in freshly prepared kimchi belonged to Bacillus genus. Lactic acid bacteria responsible for kimchi fermentation began to grow on day 4, and were completely substituted for Bacillus genus on day 8, but some Bacillus genus began to grow again on day 12. However, bacterial community diversities were not different based on varying EP intensity. 相似文献
103.
104.
105.
Christopher I Keeling Macaire MS Yuen Nancy Y Liao T Roderick Docking Simon K Chan Greg A Taylor Diana L Palmquist Shaun D Jackman Anh Nguyen Maria Li Hannah Henderson Jasmine K Janes Yongjun Zhao Pawan Pandoh Richard Moore Felix AH Sperling Dezene P W Huber Inanc Birol Steven JM Jones Joerg Bohlmann 《Genome biology》2013,14(3):R27
106.
Fernanda Hurbath BÁrbara SimÕes Santos Leal Otávio Luis Marques Da Silva Clarisse Palma-Silva INês Cordeiro 《分类学与生物多样性》2013,11(7):658-667
A new species of Euphorbia sect. Brasilienses V.W. Steinm. & Dorsey is described. Euphorbia tetrangularis Hurbath & Cordeiro is endemic to the Serra de Montevidéu, a part of the Espinhaço Range located in the state of Minas Gerais, Brazil. It differs from other species within the section based on the following characters: 4-ribbed branches, green cyathia, and green cyathial glands with erect appendages. This new species would qualify as critically endangered (CR) according to IUCN criteria. An inferred phylogeny based on a combined dataset of nuclear (ITS1) and plastid regions (psbA-trnH, trnC-ycf6, matK, atpI-atpH, psbJ-petA, trnQ-rps16?×?1) confirms the monophyly of Euphorbia sect. Brasilienses and supports the recognition of E. tetrangularis. The phylogeny also suggests that this group probably underwent a recent radiation. 相似文献
107.
Evelyn Walenta Ariane R. Pessentheiner Helmut J. Pelzmann Alexander Deutsch Madeleine Goeritzer Dagmar Kratky Hubert Hackl Da Young Oh Andreas Prokesch Juliane G. Bogner-Strauss 《PloS one》2013,8(11)
Our knowledge about adipocyte metabolism and development is steadily growing, yet many players are still undefined. Here, we show that α/β-hydrolase domain containing protein 15 (Abhd15) is a direct and functional target gene of peroxisome proliferator-activated receptor gamma (PPARγ), the master regulator of adipogenesis. In line, Abhd15 is mainly expressed in brown and white adipose tissue and strongly upregulated during adipogenesis in various murine and human cell lines. Stable knockdown of Abhd15 in 3T3-L1 cells evokes a striking differentiation defect, as evidenced by low lipid accumulation and decreased expression of adipocyte marker genes. In preconfluent cells, knockdown of Abhd15 leads to impaired proliferation, which is caused by apoptosis, as we see an increased SubG1 peak, caspase 3/7 activity, and BAX protein expression as well as a reduction in anti-apoptotic BCL-2 protein. Furthermore, apoptosis-inducing amounts of palmitic acid evoke a massive increase of Abhd15 expression, proposing an apoptosis-protecting role for ABHD15. On the other hand, in mature adipocytes physiological (i.e. non-apoptotic) concentrations of palmitic acid down-regulate Abhd15 expression. Accordingly, we found that the expression of Abhd15 in adipose tissue is reduced in physiological situations with high free fatty acid levels, like high-fat diet, fasting, and aging as well as in genetically obese mice. Collectively, our results position ABHD15 as an essential component in the development of adipocytes as well as in apoptosis, thereby connecting two substantial factors in the regulation of adipocyte number and size. Together with its intricate regulation by free fatty acids, ABHD15 might be an intriguing new target in obesity and diabetes research. 相似文献
108.
Stefano Da Sacco Kevin V. Lemley Sargis Sedrakyan Ilenia Zanusso Astgik Petrosyan Janos Peti-Peterdi James Burford Roger E. De Filippo Laura Perin 《PloS one》2013,8(12)
Amniotic fluid is in continuity with multiple developing organ systems, including the kidney. Committed, but still stem-like cells from these organs may thus appear in amniotic fluid. We report having established for the first time a stem-like cell population derived from human amniotic fluid and possessing characteristics of podocyte precursors. Using a method of triple positive selection we obtained a population of cells (hAKPC-P) that can be propagated in vitro for many passages without immortalization or genetic manipulation. Under specific culture conditions, these cells can be differentiated to mature podocytes. In this work we compared these cells with conditionally immortalized podocytes, the current gold standard for in vitro studies. After in vitro differentiation, both cell lines have similar expression of the major podocyte proteins, such as nephrin and type IV collagen, that are characteristic of mature functional podocytes. In addition, differentiated hAKPC-P respond to angiotensin II and the podocyte toxin, puromycin aminonucleoside, in a way typical of podocytes. In contrast to immortalized cells, hAKPC-P have a more nearly normal cell cycle regulation and a pronounced developmental pattern of specific protein expression, suggesting their suitability for studies of podocyte development for the first time in vitro. These novel progenitor cells appear to have several distinct advantages for studies of podocyte cell biology and potentially for translational therapies. 相似文献
109.
110.
Hui-Fen Zheng Ya-Ping Yang Li-Fang Hu Mei-Xia Wang Fen Wang Li-Dan Cao Da Li Cheng-Jie Mao Kang-Ping Xiong Jian-Da Wang Chun-Feng Liu 《PloS one》2013,8(8)