全文获取类型
收费全文 | 682篇 |
免费 | 32篇 |
国内免费 | 2篇 |
出版年
2024年 | 1篇 |
2023年 | 2篇 |
2022年 | 1篇 |
2021年 | 11篇 |
2020年 | 4篇 |
2019年 | 17篇 |
2018年 | 10篇 |
2017年 | 19篇 |
2016年 | 26篇 |
2015年 | 22篇 |
2014年 | 18篇 |
2013年 | 39篇 |
2012年 | 59篇 |
2011年 | 62篇 |
2010年 | 40篇 |
2009年 | 32篇 |
2008年 | 55篇 |
2007年 | 37篇 |
2006年 | 31篇 |
2005年 | 34篇 |
2004年 | 30篇 |
2003年 | 33篇 |
2002年 | 29篇 |
2001年 | 6篇 |
2000年 | 3篇 |
1999年 | 18篇 |
1998年 | 10篇 |
1997年 | 7篇 |
1996年 | 5篇 |
1995年 | 5篇 |
1994年 | 4篇 |
1993年 | 4篇 |
1992年 | 1篇 |
1991年 | 8篇 |
1990年 | 3篇 |
1989年 | 4篇 |
1988年 | 1篇 |
1987年 | 3篇 |
1986年 | 3篇 |
1985年 | 5篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 5篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1973年 | 1篇 |
1958年 | 1篇 |
排序方式: 共有716条查询结果,搜索用时 184 毫秒
101.
Chiaki Sato Atushi Katumata Ikuo Takashima Nobuo Hashimoto 《FEMS microbiology letters》1991,80(2-3):201-206
Abstract: Genes from Chlamydia psittaci P-1041 were cloned into the Bam HI site of pUC19 and were transformed to host Escherichia coli JM109. Two recombinant plasmids that expressed protein antigens of Chlamydia were isolated. The sizes of the DNA fragments were 1350 and 1710 bp, and encoded for polypeptides of M r 25 and 42 kilodaltons (kDa), respectively. The 25-kDa protein had cross-reactivity with antisera to ten C. psittaci strains and two C. trachomatis strains, whereas the 42-kDa protein reacted only with homologous antiserum to the C. psittaci P-1041 strain. Furthermore, in Southern hybridization analysis these two fragments as probes hybridized with DNA of ten C. psittaci strains and four C. trachomatis strains. These results indicated that the two fragments shared a DNA sequence common to the chlamydial genus. 相似文献
102.
A new enzyme has been obtained in a crystalline state from the muscle of blue white dolphin. This enzyme resembles to methemoglobin reductase from erythrocyte with respect to (a) elution pattern of DEAE-Sephadex column chromatography, (b) absorption spectra, (c) molecular weight and (d) activity of reducing methemoglobin, metmyoglobin and ferric cytochrome c. However, distinct differences can be observed between two enzymes with regard to (a) sedimentation coefficient, (b) diffusion coefficient, (c) frictional ratio, (d) pH-mobility curve and (e) specific activity of reducing the above three substrates. It is advocated that enzyme is termed metmyoglobin reductase. 相似文献
103.
Hisataka Kitano Chiaki Hidai 《Biochemical and biophysical research communications》2010,393(4):757-761
Mouse Del1 is an extracellular matrix protein mainly expressed in the developing embryo. Del1 has three EGF motifs and two discoidin domains. The second EGF motif reportedly contains an RGD sequence that binds to integrin receptors. Here, we provide evidence that Del1 protein induces cell death in vitro. Chromatin condensation and DNA laddering were observed, suggestive of apoptosis. The results of analysis using the TUNEL method and annexin V staining were also consistent with apoptosis. The apoptosis-inducing activity of Del1 could be mapped to the third EGF motif, which fitted the consensus sequence CX(D/N)XXXX(F/Y)XCXC, wherein the aspartic acid residue (D) could be β-hydroxylated. As little as twenty-five picomolar of recombinant E3 could induce apoptosis. 相似文献
104.
Chiaki Motegi Toshi Nagata Takeshi Miki Markus G. Weinbauer Louis Legendre Fereidoun Rassoulzadegan 《PloS one》2013,8(11)
A general model of species diversity predicts that the latter is maximized when productivity and disturbance are balanced. Based on this model, we hypothesized that the response of bacterial diversity to the ratio of viral to bacterial production (VP/BP) would be dome-shaped. In order to test this hypothesis, we obtained data on changes in bacterial communities (determined by terminal restriction fragment length polymorphism of 16S rRNA gene) along a wide VP/BP gradient (more than two orders of magnitude), using seawater incubations from NW Mediterranean surface waters, i.e., control and treatments with additions of phosphate, viruses, or both. In December, one dominant Operational Taxonomic Unit accounted for the major fraction of total amplified DNA in the phosphate addition treatment (75±20%, ± S.D.), but its contribution was low in the phosphate and virus addition treatment (23±19%), indicating that viruses prevented the prevalence of taxa that were competitively superior in phosphate-replete conditions. In contrast, in February, the single taxon predominance in the community was held in the phosphate addition treatment even with addition of viruses. We observed statistically robust dome-shaped response patterns of bacterial diversity to VP/BP, with significantly high bacterial diversity at intermediate VP/BP. This was consistent with our model-based hypothesis, indicating that bacterial production and viral-induced mortality interactively affect bacterial diversity in seawater. 相似文献
105.
106.
HMGB1‐induced inflammatory response promotes bone healing in murine tooth extraction socket 下载免费PDF全文
107.
Increased Levels of Monodehydroascorbate Radical in UV-B-Irradiated Broad Bean Leaves 总被引:1,自引:0,他引:1
Light-induced monodehydroascorbate (MDA) radical productionwas not detectable by EPR spectroscopy in untreated broad beanleaves, but it was observed after exposing the leaves to UV-B(280320 nm) irradiation. After this pre-treatment, alow level of MDA radicals was also detectable without illumination.Light-induced MDA, MDA production in the dark, oxygen evolution,quantum yield of PSII as measured by Chi fluorescence, MDA producingand reducing enzyme activities were determined and comparedin leaves after irradiation with various doses of UV-B. Ourresults suggest that UV-B irradiation disturbs the balance ofMDA radical production and reduction, resulting in increasedlight induced MDA signal. The enhancement of ascorbate photooxidationat the UV-B damaged donor side of PSII appears as a major factorin this process. (Received November 22, 1996; Accepted March 25, 1997) 相似文献
108.
H. Tamegai Lina Li Noriaki Masui Chiaki Kato 《Extremophiles : life under extreme conditions》1997,1(4):207-211
The denitrifying bacterium strain MT-1 was isolated from the mud of the Mariana Trench. The optimal temperature and pressure
for growth of this bacterium were found to be 30°C and 0.1 MPa, respectively. However, it showed greater tolerance to low
temperature (4°C) and high hydrostatic pressure (50 MPa) as compared with denitrifiers obtained from land. From the results,
it can be said that this organism is adapted to the environment of the deep sea. Strain MT-1 was shown to belong to the genus
Pseudomonas by analysis of its 16S rDNA. The cytochrome contents of the bacterium were similar to those of Ps. stutzeri in spectrophotometric studies.
Received: June 2, 1997 / Accepted: August 9, 1997 相似文献
109.
The molecular biology of barophilic bacteria 总被引:4,自引:1,他引:3
Many microorganisms from the deep-sea display high-pressure-adapted — also described as barophilic or piezophilic — growth
characteristics. Phylogenetic studies have revealed that a large proportion of the barophilic bacteria currently in culture
collections belong to a distinct subgroup of the genus Shewanella, referred to as the “barophile branch.“ Many of the basic properties of barophiles that enable their survival at extremes
of pressure remain to be elucidated. However, several genes whose expression is regulated by pressure, or which appear to
be critical to baroadaptation, have been uncovered. One such operon, whose presence appears to be restricted to the “barophile
branch,” has been identifed in DNA samples obtained from sediments recovered in the deepest ocean trench. In the case of another
set of pressure-regulated genes, regulatory elements required for pressure signaling have been uncovered. The nature and regulation
of these genes is discussed.
Received: February 19, 1997 / Accepted: March 3, 1997 相似文献
110.
Takeshi Kobayashi Chihiro Taguchi Kakeru Kida Hiroko Matsuda Takeshi Terahara Chiaki Imada Nant Kay Thwe Moe Su Myo Thwe 《World journal of microbiology & biotechnology》2016,32(10):166
The distribution and characterization of bacteria including lactic acid bacteria (LAB) in the traditional and popular salted fish yegyo ngapi in Myanmar were studied to clarify the contribution of these bacteria to the curing and ripening of this product. Samples of yegyo ngapi purchased from a market in Yangon were used. Most of the isolates obtained using de Man, Rogosa and Sharpe medium containing 10 % NaCl were identified as coccoid LAB on the basis of their basic phenotypic characteristics. From the results of 16S rRNA gene sequencing and PCR-restriction fragment length polymorphism analysis of this gene, most of the isolates were identified as the halophilic LAB Tetragenococcus muriaticus. Analyses of the 16S rRNA gene based on the clone library using DNA extracted from salted fish products were also performed. The results of these molecular-analysis-based techniques showed that spore-forming and non-spore-forming anaerobic bacteria including the genera Clostridium and Halanaerobium in addition to T. muriaticus were also frequently found in bacterial communities. These findings suggest that the anaerobic condition during curing and ripening resulted in bacterial communities composed of strictly anaerobic bacteria and halophilic LAB, and that these bacteria might also contribute to the manufacturing processes of this product. In addition, DNA sequences similar to that of Clostridium botulinum were found in the clone library analysis. Therefore, despite no reports of botulism poisoning from the region where the samples were taken, closer surveillance should be carried out from the viewpoint of food safety. 相似文献