全文获取类型
收费全文 | 4422篇 |
免费 | 244篇 |
国内免费 | 1篇 |
出版年
2022年 | 20篇 |
2021年 | 53篇 |
2020年 | 27篇 |
2019年 | 37篇 |
2018年 | 65篇 |
2017年 | 60篇 |
2016年 | 82篇 |
2015年 | 133篇 |
2014年 | 154篇 |
2013年 | 257篇 |
2012年 | 276篇 |
2011年 | 285篇 |
2010年 | 172篇 |
2009年 | 148篇 |
2008年 | 270篇 |
2007年 | 269篇 |
2006年 | 261篇 |
2005年 | 231篇 |
2004年 | 227篇 |
2003年 | 195篇 |
2002年 | 214篇 |
2001年 | 113篇 |
2000年 | 113篇 |
1999年 | 99篇 |
1998年 | 52篇 |
1997年 | 56篇 |
1996年 | 28篇 |
1995年 | 22篇 |
1994年 | 33篇 |
1993年 | 22篇 |
1992年 | 71篇 |
1991年 | 58篇 |
1990年 | 57篇 |
1989年 | 50篇 |
1988年 | 76篇 |
1987年 | 46篇 |
1986年 | 35篇 |
1985年 | 26篇 |
1984年 | 33篇 |
1983年 | 22篇 |
1982年 | 21篇 |
1981年 | 11篇 |
1980年 | 15篇 |
1979年 | 21篇 |
1978年 | 24篇 |
1975年 | 16篇 |
1974年 | 13篇 |
1973年 | 19篇 |
1971年 | 12篇 |
1968年 | 9篇 |
排序方式: 共有4667条查询结果,搜索用时 31 毫秒
921.
Thaís Teixeira-Rios Danielle Karla Alves da Silva Bruno Tomio Goto Adriana Mayumi Yano-Melo 《Folia Geobotanica》2018,53(2):191-200
Tropical dry forests are strongly affected by seasonality, but its effects on belowground communities are poorly studied. Thus, the objective of this study was to reveal the effect of the season (dry versus wet) on the mycorrhizal status of roots and their potential colonization, and to determine the composition and abundance of spore-based communities of arbuscular mycorrhizal fungi (AMF) in rhizospheric soil of two dominant woody species in caatinga communities (tropical dry forest of the Brazilian Northeast). Soil and root samples were taken four times in each season (dry and wet). In the cases of the number of glomerospores and the number of infective propagules of AMF, there were significant differences between the hosts, with greater values observed in the rhizosphere of Commiphora leptophloeos than Mimosa tenuiflora. Mycorrhizal colonization and the number of infective propagules of AMF differed also between the seasons, being higher in the dry than the wet season. In total, fourteen AMF species were found in the rhizosphere of C. leptophloeos and twelve species were associated with M. tenuiflora. There was a predominance of the fungal genus Acaulospora, with seven species, followed by Gigaspora and Glomus. The species studied and the seasons differ in the composition and structure of the AMF community in the rhizosphere of the plants. The ecological significance of those differences needs to be examined further. 相似文献
922.
Tomohiro Koga Shuntaro Sato Junya Miyamoto Naoko Hagimori Yurika Kawazoe Kumiko Arinaga Chizu Fukushima Hiroshi Yamamoto Atsushi Kawakami 《Trials》2018,19(1):715
Background
Familial Mediterranean fever (FMF) is an inherited disorder caused by a number of mutations of the Mediterranean fever (MEFV) gene, coding a protein named pyrin that acts as a major regulatory component of the inflammasome. The first-line drug for FMF treatment is colchicine, but 10% of patients with FMF do not respond well to colchicine. Although the efficacy of tocilizumab (TCZ), which is a recombinant, humanized, antihuman interleukin 6 (IL-6) receptor monoclonal antibody, has been reported to prevent FMF attacks, the effects of TCZ on individuals with colchicine-resistant or colchicine-intolerant FMF have not been evaluated in a randomized clinical trial.Methods/design
In this phase III, investigator-initiated, multicenter, double-blind, randomized, parallel-group trial, the efficacy and safety of TCZ will be compared with placebo in patients with colchicine-resistant or colchicine-intolerant FMF. The study will be conducted in nine centers in Japan. Participants (n =?24) will be randomly assigned to receive 162?mg of TCZ (n =?12) or placebo (n =?12) administered subcutaneously once weekly for 24?weeks. Rescue treatment will be allowed if rescue criteria are met. A primary endpoint is the number of fever attacks until 24?weeks. Secondary endpoints include the number of occurrences of accompanying symptoms during attacks; the time until a fever attack occurs; the duration of fever attacks; serum C-reactive protein and serum amyloid A; 36-item Short Form Health Survey; general evaluation by a physician (100-mm visual analogue scale); body temperature; the percentage of subjects who achieve FMF 50 at 12?weeks and 24?weeks; and pharmacodynamic assessment, including the measurement of serum TCZ level and soluble IL-6 receptor.Discussion
The study is expected to produce evidence regarding the efficacy of a potential new therapeutic agent, TCZ, in improving the clinical course and outcome for patients with colchicine-resistant or colchicine-intolerant FMF.Trial registration
University Hospital Medical Information Network Clinical Trials Registry, UMIN000028010. Registered on 7 July 2017.923.
Taku Wakabayashi Hisamichi Naito Jun-ichi Suehiro Yang Lin Hideya Kawaji Tomohiro Iba Tsukasa Kouno Sachi Ishikawa-Kato Masaaki Furuno Kazuhiro Takara Fumitaka Muramatsu Jia Weizhen Hiroyasu Kidoya Katsuhiko Ishihara Yoshihide Hayashizaki Kohji Nishida Mervin C. Yoder Nobuyuki Takakura 《Cell Stem Cell》2018,22(3):384-397.e6
924.
Tumor‐suppressive roles of ΔNp63β‐miR‐205 axis in epithelial–mesenchymal transition of oral squamous cell carcinoma via targeting ZEB1 and ZEB2
下载免费PDF全文
![点击此处可从《Journal of cellular physiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Yuma Hashiguchi Shintaro Kawano Yuichi Goto Kaori Yasuda Naoki Kaneko Taiki Sakamoto Ryota Matsubara Teppei Jinno Yasuyuki Maruse Hideaki Tanaka Masahiko Morioka Taichi Hattori Shoichi Tanaka Tamotsu Kiyoshima Seiji Nakamura 《Journal of cellular physiology》2018,233(10):6565-6577
We previously revealed that epithelial‐to‐mesenchymal transition (EMT) was mediated by ΔNp63β, a splicing variant of ΔNp63, in oral squamous cell carcinoma (OSCC). Recent studies have highlighted the involvement of microRNA (miRNA) in EMT of cancer cells, though the mechanism remains unclear. To identify miRNAs responsible for ΔNp63β‐mediated EMT, miRNA microarray analyses were performed by ΔNp63β‐overexpression in OSCC cells; SQUU‐B, which lacks ΔNp63 expression and displays EMT phenotypes. miRNAs microarray analyses revealed miR‐205 was the most up‐regulated following ΔNp63β‐overexpression. In OSCC cells, miR‐205 expression was positively associated with ΔNp63 and negatively with zinc‐finger E‐box binding homeobox (ZEB) 1 and ZEB2, potential targets of miR‐205. miR‐205 overexpression by miR‐205 mimic transfection into SQUU‐B cells led to decreasing ZEB1, ZEB2, and mesenchymal markers, increasing epithelial markers, and reducing cell motilities, suggesting inhibition of EMT phenotype. Interestingly, the results opposite to this phenomenon were obtained by transfection of miR‐205 inhibitor into OSCC cells, which express ΔNp63 and miR‐205. Furthermore, target protector analyses revealed direct regulation by miR‐205 of ZEB1 and ZEB2 expression. These results showed tumor‐suppressive roles of ΔNp63β and miR‐205 by inhibiting EMT thorough modulating ZEB1 and ZEB2 expression in OSCC. 相似文献
925.
Tomohiro Matsuoka 《Bioscience, biotechnology, and biochemistry》2018,82(9):1652-1655
Rhodococcus erythropolis N9T-4 grows on an inorganic solid-state medium with no additional carbon and energy sources; however, it is unable to grow well in a liquid culture medium under the oligotrophic conditions. We examined submerged cultivations of N9T-4 using a polyurethane foam sponge to achieve approximately 10 times of the oligotrophic growth of the bacterium in the liquid culture medium. 相似文献
926.
Wataru Arai Takeaki Taniguchi Susumu Goto Yuki Moriya Hideya Uehara Kazuhiro Takemoto 《Bioscience, biotechnology, and biochemistry》2018,82(9):1515-1517
MAPLE is an automated system for inferring the potential comprehensive functions harbored by genomes and metagenomes. To reduce runtime in MAPLE analyzing the massive amino acid datasets of over 1 million sequences, we improved it by adapting the KEGG automatic annotation server to use GHOSTX and verified no substantial difference in the MAPLE results between the original and new implementations. 相似文献
927.
Yukinori Yabuta Haruka Mukoyama Yoshimi Kaneda Narisa Kimura Tomohiro Bito Tsuyoshi Ichiyanagi 《Bioscience, biotechnology, and biochemistry》2018,82(9):1584-1590
Streptococcus mutans is a bacterium found in human oral biofilms (dental plaques) that is associated with the development of dental caries. Glucosyltransferases (GTFs) are key enzymes involved in dental plaque formation, and compounds that inhibit their activities may prevent dental caries. We developed a screening system for GTF-inhibitory activities, and used it to profile 44 types of herbal tea extracts. Lemon myrtle (Backhousia citriodora) extract exhibited the highest GTF-inhibitory activity, with an IC50 for GTF in solution of 0.14 mg mL?1. Furthermore, lemon myrtle extracts had the third-highest polyphenol content of all tested extracts, and strongly inhibited S. mutans biofilm. Interestingly, lemon myrtle extracts did not inhibit cell growth. 相似文献
928.
Hidenobu Murafuji Hiroki Sakai Megumi Goto Yoshiaki Oyama Seiichi Imajo Hajime Sugawara Toshiyuki Tomoo Tsuyoshi Muto 《Bioorganic & medicinal chemistry letters》2018,28(8):1371-1375
A novel series of 1,3,6-trisubstituted 1,4-diazepan-7-ones were investigated as human kallikrein 7 (KLK7, stratum corneum chymotryptic enzyme) inhibitors. Based on the X-ray co-crystal structure of compound 1 bound to human KLK7, the derivatives of this scaffold were designed, synthesized, and evaluated. Through structure-activity relationship studies focused on the side chain located in the prime site region of the enzyme, representative compounds 15, 33a, and 35a were identified as highly potent and selective inhibitors of human KLK7. 相似文献
929.
High-rate nitrogen removal from waste brine by marine anammox bacteria in a pilot-scale UASB reactor
Yokota Nobuyuki Watanabe Yasutsugu Tokutomi Takaaki Kiyokawa Tomohiro Hori Tomoyuki Ikeda Daisuke Song Kang Hosomi Masaaki Terada Akihiko 《Applied microbiology and biotechnology》2018,102(3):1501-1512
Applied Microbiology and Biotechnology - The goal of this study was to develop a startup strategy for a high-rate anaerobic ammonium oxidation (anammox) reactor to treat waste brine with high... 相似文献
930.
Asako Kaise Kiminori Ohta Shinya Fujii Akifumi Oda Tokuhito Goto Yasuyuki Endo 《Bioorganic & medicinal chemistry》2018,26(13):3805-3811
Based on the co-crystal structure of bicalutamide with a T877A-mutated androgen receptor (AR), glycerol and aminoglycerol derivatives were designed and synthesized as a novel type of carborane-containing AR modulators. The (R)-isomer of 6c, whose chirality is derived from the glycerol group, showed 20 times more potent cell inhibitory activity against LNCaP cell lines expressing T877A-mutated AR than the corresponding (S)-isomer. Docking studies of both isomers with AR suggested that (R)-6c is in closer spatial proximity to helix-12 of the AR than (S)-6c, which is the most important common motif in the secondary structure of AR for the expression of antagonistic activity. 相似文献