全文获取类型
收费全文 | 7924篇 |
免费 | 709篇 |
国内免费 | 575篇 |
专业分类
9208篇 |
出版年
2024年 | 20篇 |
2023年 | 114篇 |
2022年 | 278篇 |
2021年 | 449篇 |
2020年 | 300篇 |
2019年 | 351篇 |
2018年 | 327篇 |
2017年 | 234篇 |
2016年 | 384篇 |
2015年 | 510篇 |
2014年 | 653篇 |
2013年 | 595篇 |
2012年 | 713篇 |
2011年 | 608篇 |
2010年 | 422篇 |
2009年 | 333篇 |
2008年 | 413篇 |
2007年 | 397篇 |
2006年 | 290篇 |
2005年 | 250篇 |
2004年 | 198篇 |
2003年 | 188篇 |
2002年 | 134篇 |
2001年 | 140篇 |
2000年 | 129篇 |
1999年 | 146篇 |
1998年 | 89篇 |
1997年 | 77篇 |
1996年 | 67篇 |
1995年 | 48篇 |
1994年 | 56篇 |
1993年 | 31篇 |
1992年 | 49篇 |
1991年 | 39篇 |
1990年 | 23篇 |
1989年 | 31篇 |
1988年 | 22篇 |
1987年 | 29篇 |
1986年 | 13篇 |
1985年 | 20篇 |
1984年 | 12篇 |
1983年 | 6篇 |
1982年 | 5篇 |
1981年 | 3篇 |
1980年 | 2篇 |
1979年 | 3篇 |
1978年 | 3篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1965年 | 1篇 |
排序方式: 共有9208条查询结果,搜索用时 15 毫秒
51.
52.
53.
Dongliang Liu Yang Li Jing Zhao Fei Deng Xiaomei Duan Chun Kou Ting Wu Yijie Li Yongxing Wang Ji Ma Jianhua Yang Zhihong Hu Fuchun Zhang Yujiang Zhang Surong Sun 《PloS one》2014,9(11)
Crimean-Congo hemorrhagic fever (CCHF), a severe viral disease known to have occurred in over 30 countries and distinct regions, is caused by the tick-borne CCHF virus (CCHFV). Nucleocapsid protein (NP), which is encoded by the S gene, is the primary antigen detectable in infected cells. The goal of the present study was to map the minimal motifs of B-cell epitopes (BCEs) on NP. Five precise BCEs (E1, 247FDEAKK252; E2a, 254VEAL257; E2b, 258NGYLNKH264; E3, 267EVDKA271; and E4, 274DSMITN279) identified through the use of rabbit antiserum, and one BCE (E5, 258NGYL261) recognized using a mouse monoclonal antibody, were confirmed to be within the central region of NP and were partially represented among the predicted epitopes. Notably, the five BCEs identified using the rabbit sera were able to react with positive serum mixtures from five sheep which had been infected naturally with CCHFV. The multiple sequence alignment (MSA) revealed high conservation of the identified BCEs among ten CCHFV strains from different areas. Interestingly, the identified BCEs with only one residue variation can apparently be recognized by the positive sera of sheep naturally infected with CCHFV. Computer-generated three-dimensional structural models indicated that all the antigenic motifs are located on the surface of the NP stalk domain. This report represents the first identification and mapping of the minimal BCEs of CCHFV-NP along with an analysis of their primary and structural properties. Our identification of the minimal linear BCEs of CCHFV-NP may provide fundamental data for developing rapid diagnostic reagents and illuminating the pathogenic mechanism of CCHFV. 相似文献
54.
In this review, the recent progress in using transient absorption microscopy to image charge transport and dynamics in semiconducting hybrid organic–inorganic perovskites is discussed. The basic principles, instrumentation, and resolution of transient absorption microscopy are outlined. With temporal resolution as high as 10 fs, sub‐diffraction‐limit spatial resolution, and excited‐state structural resolution, these experiments have provided crucial details on charge transport mechanisms that have been previously obscured in conventional ultrafast spectroscopy measurements. Morphology‐dependent mapping unveils spatial heterogeneity in carrier recombination and cooling dynamics. By spatially separating the pump and probe beams, carrier transport across grain boundaries has been directly visualized. Further, femtosecond temporal resolution allows for the examination of nonequilibrium transport directly, revealing extraordinarily long‐range hot carrier migration. The application of transient absorption microscopy is not limited to hybrid perovskites but can also be useful for other polycrystalline materials in which morphology plays an important role in carrier transport. 相似文献
55.
Naixiong Peng Zejian Zhang Yaomin Wang Minlong Yang Jiqing Fan Qinjun Wang Ling Deng Dong Chen Yuefeng Cai Qihui Li Xisheng Wang Wei Li 《Journal of cellular and molecular medicine》2021,25(22):10627-10637
Prostate cancer is the second most frequent malignancy in men worldwide, and its incidence is increasing. Therefore, it is urgently required to clarify the underlying mechanisms of prostate cancer. Although the long non-coding RNA LINC00115 was identified as an oncogene in several cancers, the expression and function of LINC00115 in prostate cancer have not been explored. Our results showed that LINC00115 was significantly up-regulated in prostate cancer tissues, which was significantly associated with a poor prognosis for prostate cancer patients. Functional studies showed that knockdown LINC00115 inhibited cell proliferation and invasion. In addition, LINC00115 served as a competing endogenous RNA (ceRNA) through sponging miR-212-5p to release Frizzled Family Receptor 5 (FZD5) expression. The expression of miR-212-5p was noticeably low in tumour tissues, and FZD5 expression level was down-regulated with the knockdown of LINC00115. Knockdown LINC00115 inhibited the Wnt/β‑catenin signalling pathway by inhibiting the expression of FZD5. Rescue experiments further showed that LINC00115 inhibits prostate cancer cell proliferation and invasion via targeting miR-212-5p/ FZD5/ Wnt/β-catenin axis. The present study provided clues that LINC00115 may be a promising novel therapeutic target for prostate cancer patients. 相似文献
56.
57.
In vitro vegetative propagation of Chinese cabbage 总被引:1,自引:0,他引:1
Explants from cotyledons, axillary buds, inflorescence stems and flower buds of Brassica campestris ssp. pekinensis (Lour.) Olsson (Chinese cabbage, cv. Wongbok) were cultured on MS medium with growth regulators. Multiple shoots were obtained from cotyledons, axillary buds and flower buds but not from inflorescence stems. Propagation of shoots from cotyledons was more successful than from axillary buds and flower buds. The vegetative propagation rates varied amongst clones derived from cotyledons of the same cultivar and seed lot. The propagation rates of the cotyledon-derived material followed a normal distribution with an average propagation rate of 2.6 shoots per two weeks subculture when cultured on MS media plus 44.4 m benzyladenine (BA) and 14.8 m -indolebutyric acid (IBA). Shoots from three clones were cultured on MS medium with nine different concentrations of BA. The concentration of BA which promoted the highest rate of shoot propagation varied for the three clones and was in the range 44.4 to 177.6 m. 相似文献
58.
Huihui Deng Ye Han Yuanyuan Liu Wei Jia Zhijiang Zhou 《Journal of industrial microbiology & biotechnology》2012,39(11):1663-1672
A new erythritol-producing yeast (strain BH010) was isolated in this study. Analysis of the D1/D2 domain of the 26S rDNA sequence, the ITS/5.8S rDNA sequence, and the 18S rDNA sequence allowed the taxonomic position of strain BH010 to be discussed and it was identified and named Moniliella sp. BH010. Physiological characteristics were described. Scanning electron micrography clearly indicated that the cells were cylindrical to elliptical with an average size of 5?×?10?μm when growing in liquid medium, and that pseudohyphae and blastoconidia were observed when cultivated in agar plates. The erythritol reductase genes were cloned, sequenced, and analyzed. BLAST analysis and multiple sequence alignment demonstrated that erythritol reductase genes of Moniliella sp. BH010 shared very high homology with that of Trichosporonoides megachiliensis SNG-42 except for the presence of introns. The deduced amino acid sequences showed high homology to the aldo–keto reductase superfamily. 相似文献
59.
60.