全文获取类型
收费全文 | 179篇 |
免费 | 26篇 |
出版年
2021年 | 2篇 |
2020年 | 2篇 |
2018年 | 1篇 |
2017年 | 2篇 |
2016年 | 5篇 |
2015年 | 8篇 |
2014年 | 2篇 |
2013年 | 10篇 |
2012年 | 15篇 |
2011年 | 3篇 |
2010年 | 6篇 |
2009年 | 5篇 |
2008年 | 10篇 |
2007年 | 8篇 |
2006年 | 11篇 |
2005年 | 15篇 |
2004年 | 7篇 |
2003年 | 9篇 |
2002年 | 6篇 |
2001年 | 3篇 |
2000年 | 6篇 |
1999年 | 5篇 |
1998年 | 1篇 |
1997年 | 5篇 |
1996年 | 1篇 |
1995年 | 3篇 |
1994年 | 6篇 |
1993年 | 2篇 |
1992年 | 4篇 |
1991年 | 1篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1988年 | 4篇 |
1987年 | 3篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1982年 | 4篇 |
1981年 | 1篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1978年 | 3篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 2篇 |
1974年 | 2篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1969年 | 2篇 |
1967年 | 4篇 |
排序方式: 共有205条查询结果,搜索用时 46 毫秒
171.
Tatsuyuki Muratake Shigenobu Hayashi Yuka Ichimura Ken Morii Ryozo Kuwano Tomio Ichikawa Toshiro Kumanishi Toshiaki Isobe Masahiko Watanabe Hisatake Kondo Yasuo Takahashi 《Molecular neurobiology》1995,11(1-3):223-230
14·3·3 protein, a brain-specific protein, is an activator of tyrosine and tryptophan hydroxylases, key enzymes for biosynthesis of dopamine and serotonin. In this article, we describe cloning of cDNA for human brain 14·3·3 ν chain and expression of 14·3·3 ν chain mRNA in some human cultured cells. The cloned cDNA is 1730 bp long and contains 191 bp of a 5′-noncoding region, the complete 738 bp of coding region, and 801 bp of a 3′-noncoding region, containing three polyadenylation signals. This cDNA encoded a polypeptide of 246 amino acids (M, 28,196). Furthermore, usingin situ hybridization histochemistry, the expression of mRNA for this protein was examined in the rat central nervous system.In situ hybridization histochemistry indicated that 14·3·3 ? chain mRNA is detected not only in the monoamine-synthetic neurons, but also in other neurons in the discrete nuclei, which synthesize neither cathecholamine nor serotonin. Northern blot analysis demonstrated that the addition of methamphetamine into the cultured medium increased the mRNA level for 14·3·3 ? chain in U-251 cells, but did not increase that of GFAP. 相似文献
172.
Ogiso Manabu; Nishiyama Ichiro; Saito Nobuyuki; Okinaga Tatsuyuki; Hoshi Motonori; Komoto Michiji 《Glycobiology》1995,5(2):187-194
Rat lens was found to contain several neutral and acidic glycosphingolipidsin lens epithelia, cortex and nucleus, and showed developmentalchanges in their content and localization. TLC-immunostainingof gangliosides revealed the enrichment of some ganglio-seriesgangliosides (GM3, GM1, GD3 and GD1b) in lens epithelia andthe presence of GM3 and GD3 in the lens nucleus. Immunohistochemicalstudies confirmed the distribution of GM3 and GM1 in anteriorlens epithelial cells and the cortex, with expression decreasingtoward the lens nucleus. Immunoreaction to GD3 was more intensein the lens nucleus than in epithelial cells. In contrast, theexpression of neolacto-series glycosphingolipids was restrictedto the lens nucleus. In order to investigate the pathologicalchanges of glycosphingolipids in cataract, galactose-inducedcataractous lenses were examined. However, no significant changeswere observed in the content and composition of glycosphingolipids.In addition, Lewisx epitopes found in human cataractous lenseswere not detected in the cataractous lenses of galactosaemicrats and hereditary cataractous Emory mice. cataract gangliosides glcosphingolipids Lewisx rat lens 相似文献
173.
K Tsujimura Y Obata Y Matsudaira S Ozeki K Yoshikawa S Saga T Takahashi 《Journal of immunology (Baltimore, Md. : 1950)》2001,167(2):759-764
Thymus leukemia (TL) Ags belong to the family of nonclassical MHC class I Ags and can be recognized by both TCRalphabeta and TCRgammadelta CTL with TL, but not H-2 restriction. We previously reported that the CTL epitope is TAP independent, but the antigenic molecule(s) presented by TL has yet to be determined. In the present study, TL tetramers were prepared with T3(b)-TL and murine beta(2)-microglobulin, not including antigenic peptides, and binding specificity was studied. CTL clones against TL Ags were stained with the T3(b)-TL tetramer, and the binding shown to be CD3 and CD8 dependent. Normal lymphocytes from various origins were also studied. Surprisingly, most CD8(+) intraepithelial lymphocytes derived from the small intestines (iIEL), as well as CD8(+) and CD4(+)CD8(+) thymocytes, were stained, while only very minor populations of CD8(+) cells derived from other peripheral lymphoid tissues, such as spleen and lymph nodes, were positive. The binding of T3(b)-TL tetramers to CD8(+) iIEL and thymocytes was CD8 dependent, but CD3 independent, in contrast to that to TL-restricted CTL. These results altogether showed that TL-restricted CTL can be monitored by CD3-dependent binding of T3(b)-TL tetramers. In addition, CD3-independent T3(b)-TL tetramer binding to iIEL and thymocytes may imply that TL expressed on intestinal epithelium and cortical thymocytes has a physiological function interacting with these tetramer(+)CD8(+) T lymphocytes. 相似文献
174.
Hiroki Furuta Tomoko Sawada Kaoru Nishikawa Ichiro Yamamoto Tatsuyuki Yoshida Minoru Tanaka 《Cytotechnology》2008,56(1):27-32
The present study was carried out to investigate development of recipient chicken embryonic reproductive tracts which are
transferred chicken primordial germ cells (PGCs). It is thought that differentiation of PGCs is affected by the gonadal somatic
cells. When female PGCs are transferred to male embryos, it is possible that they differentiate to W-spermatogonia. However,
the relationship development between PGCs and gonads has not been investigated. At stage 12–15 of incubation of fertilized
eggs, donor PGCs, which were taken from the blood vessels of donor embryos, were injected into the blood vessels of recipient
embryos. The gonads were removed from embryos that died after 16 days of incubation and from newly hatched chickens and organs
were examined for morphological and histological features. The survival rate of the treated embryos was 13.6% for homo-sexual
transfer of PGCs (male PGCs to male embryo or female PGCs to female embryo) and 28.9% for hetero-sexual transfer PGCs (male
PGCs to female embryo or female PGCs to male embryo) when determined at 15 days of incubation. The gonads of embryos arising
from homo-sexual transfer appeared to develop normally. In contrast, embryos derived from hetero-sexual transfer of PGCs had
abnormal gonads as assessed by histological observation. These results suggest that hetero-sexual transfer of PGCs may influence
gonadal development early-stage embryos. 相似文献
175.
Evans JG Correia I Krasavina O Watson N Matsudaira P 《The Journal of cell biology》2003,161(4):697-705
Podosomes are actin- and fimbrin-containing adhesions at the leading edge of macrophages. In cells transfected with beta-actin-ECFP and L-fimbrin-EYFP, quantitative four-dimensional microscopy of podosome assembly shows that new adhesions arise at the cell periphery by one of two mechanisms; de novo podosome assembly, or fission of a precursor podosome into daughter podosomes. The large podosome cluster precursor also appears to be an adhesion structure; it contains actin, fimbrin, integrin, and is in close apposition to the substratum. Microtubule inhibitors paclitaxel and demecolcine inhibit the turnover and polarized formation of podosomes, but not the turnover rate of actin in these structures. Because daughter podosomes and podosome cluster precursors are preferentially located at the leading edge, they may play a critical role in continually generating new sites of cell adhesion. 相似文献
176.
Vazquez M McKinley G Mitnik L Desmarais S Matsudaira P Ehrlich D 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2002,779(2):163-171
Optimization of electrophoretic techniques is becoming an increasingly important area of research as microdevices are now routinely adapted for numerous biology and engineering applications. The present work seeks to optimize electrophoresis within microdevices by utilizing ultra-high voltages to increase sample concentration prior to separation. By imaging fluorescently-tagged DNA samples, the effects of both conventional and atypical voltage protocols on DNA migration and separation are readily observed. Experiments illustrate that short periods of high voltage during electrophoretic injection do not destroy the quality of DNA separations, and in fact can enhance sample concentration five-fold. This study presents data that illustrate increases in average resolution, and resolution of longer fragments, obtained from electrophoretic injections utilizing voltages between 85 and 850 V/cm. 相似文献
177.
Iwasaki T Murata M Ohshima S Miyake T Kudo S Inoue Y Narita M Yoshimura T Akiba S Tango T Yoshimoto Y Shimizu Y Sobue T Kusumi S Yamagishi C Matsudaira H 《Radiation research》2003,159(2):228-238
IA cohort study of nuclear industry workers was initiated in 1990 to determine the possible health effects of low-level radiation. A total of 5,527 deaths were ascertained among 176,000 male workers who had been retrospectively and/or prospectively followed for an average of 7.9 years during the observation period 1986-1997. Statistical analyses were made mainly on the prospective follow-up outcome of 120,000 workers followed for an average of 4.5 years. The standardized mortality ratio (and its 95% confidence interval) was 0.94 (0.90, 0.97) for 2,934 cases of all causes combined and 0.86 (0.82, 0.91) for 1,305 cases of non-malignant diseases combined, which suggested a healthy worker effect. For 1,191 cases of all cancers combined, it was 0.98 (0.93, 1.04), indicating no difference in mortality from that of the general population. In tests for trend of death rate with increasing radiation dose, no significant correlation was found for all cancers combined. For site-specific cancers, most cancers including leukemia showed no positive correlation with dose, except for cancers of the esophagus, stomach and rectum and multiple myeloma. External causes showed a significant correlation with dose. A separate questionnaire study indicated that these positive findings could be ascribed in part to lifestyle characteristics of the workers. For leukemia only, we attempted to estimate the excess relative risk per unit dose of radiation, which, with reservations because of its wide confidence interval, was within the range of variation of the risks reported in other radiation epidemiological studies. This population must be studied for a longer time and with a consideration of the possible effects of confounding factors. 相似文献
178.
In the presence of an acid catalyst, alpha-alkyl-substituted (Z)-vinylsilanes 1, bearing a tosylamino group, were smoothly cyclized to trans-2-alkyl-3-silylpiperidines 2 (1,2-silyl-migration products) and (2R*, 1'S*)-2-(1'-silylalkyl)pyrrolidines 3. The elaboration of the reaction conditions enabled the selective preparation of each cyclized product. The acid-catalyzed cyclization of (Z)-vinylsilane 5, whose methylene tether is shorter than that of 1 by one carbon, formed only the 1,2-silyl-migration product 6 with high trans-selectivity. These cyclizations were found to proceed in a stereospecific manner. 相似文献
179.
The Saccharomyces cerevisiae calponin/transgelin homolog Scp1 functions with fimbrin to regulate stability and organization of the actin cytoskeleton
下载免费PDF全文
![点击此处可从《Molecular biology of the cell》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Calponins and transgelins are members of a conserved family of actin-associated proteins widely expressed from yeast to humans. Although a role for calponin in muscle cells has been described, the biochemical activities and in vivo functions of nonmuscle calponins and transgelins are largely unknown. Herein, we have used genetic and biochemical analyses to characterize the budding yeast member of this family, Scp1, which most closely resembles transgelin and contains one calponin homology (CH) domain. We show that Scp1 is a novel component of yeast cortical actin patches and shares in vivo functions and biochemical activities with Sac6/fimbrin, the one other actin patch component that contains CH domains. Purified Scp1 binds directly to filamentous actin, cross-links actin filaments, and stabilizes filaments against disassembly. Sequences in Scp1 sufficient for actin binding and cross-linking reside in its carboxy terminus, outside the CH domain. Overexpression of SCP1 suppresses sac6Delta defects, and deletion of SCP1 enhances sac6Delta defects. Together, these data show that Scp1 and Sac6/fimbrin cooperate to stabilize and organize the yeast actin cytoskeleton. 相似文献
180.
Nakatsukasa E Kashiwazaki N Takizawa A Shino M Kitada K Serikawa T Hakamata Y Kobayashi E Takahashi R Ueda M Nakashima T Nakagata N 《Comparative medicine》2003,53(6):639-641
We attempted to cryopreserve spermatozoa from closed colonies (Jcl:SD and Jcl:Wistar), and inbred (BN/Crj, F3441 DuCrj, LEW/Crj, Long-Evans and WKY/NCrj), mutant (Zitter [WTC.ZI-zi] and Tremor [TRM]), transgenic (human A-transferase [A], and green fluorescent protein [GFP]) strains of rats. Rat epididymal spermatozoa suspended in cryopreservation solution (23% egg yolk, 8% lactose monohydrate, and 0.7% Equex Stm, pH 7.4, adjusted with 10% Tris [hydroxymethy] aminomethane) were frozen and stored at -196 degrees C. After thawing at 37 degrees C, the spermatozoa were instilled into the tip of each uterine horn of the recipients. A total of five recipient females for each strain were inseminated with cryopreserved spermatozoa, and normal live offspring of all strains (Jcl:SD: 11, Jcl:Wistar: 13, BN/Crj: 9, F344/DuCrj: 28, LEW/Crj: 4, Long-Evans: 6, WKY/NCrj: 8, TRM: 24, WTC.ZI-zi: 27, A: 30 and GFP: 20) were obtained. 相似文献