首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1223篇
  免费   81篇
  国内免费   1篇
  1305篇
  2022年   4篇
  2021年   5篇
  2020年   12篇
  2019年   13篇
  2018年   15篇
  2017年   9篇
  2016年   14篇
  2015年   24篇
  2014年   36篇
  2013年   92篇
  2012年   63篇
  2011年   46篇
  2010年   33篇
  2009年   43篇
  2008年   65篇
  2007年   72篇
  2006年   58篇
  2005年   59篇
  2004年   61篇
  2003年   65篇
  2002年   55篇
  2001年   45篇
  2000年   39篇
  1999年   40篇
  1998年   32篇
  1997年   13篇
  1996年   12篇
  1995年   15篇
  1994年   11篇
  1993年   8篇
  1992年   28篇
  1991年   28篇
  1990年   20篇
  1989年   15篇
  1988年   18篇
  1987年   12篇
  1986年   13篇
  1985年   13篇
  1984年   8篇
  1983年   12篇
  1982年   7篇
  1981年   4篇
  1980年   10篇
  1979年   6篇
  1978年   4篇
  1976年   9篇
  1975年   5篇
  1974年   7篇
  1972年   7篇
  1971年   4篇
排序方式: 共有1305条查询结果,搜索用时 11 毫秒
991.
992.
993.
We characterized Japanese macaque (Macaca fuscata) hematopoietic cells using flow cytometry and identified 28 cross-reactive anti-human antibody clones. Furthermore, productive infection of peripheral T lymphocytes with simian immunodeficiency virus (SIV) in vitro was confirmed by intracellular SIV p27 staining. This study could facilitate using Japanese macaques as models for human hematological and immunological disorders and infectious diseases.  相似文献   
994.
Mitochondria in endothelial cells remodel morphologically when supraphysiological cyclic stretch is exerted on the cells. During remodeling, mitochondria become shorter, but how they do so remains elusive. Drp1 is a regulator of mitochondrial morphologies. It shortens mitochondria by shifting the balance from mitochondrial fusion to fission. In this study, we hypothesized that Drp1 activation is involved in mitochondrial remodeling under supraphysiological cyclic stretch. To verify the involvement of Drp1, its activation was first quantified with Western blotting, but Drp1 was not significantly activated in endothelial cells under supraphysiological cyclic stretch. Next, Drp1 activation was inhibited with Mdivi-1, but this did not inhibit mitochondrial remodeling. Intracellular Ca2+ increase activates Drp1 through calcineurin. First, we inhibited the intracellular Ca2+ increase with Gd3+ and thapsigargin, but this did not inhibit mitochondrial remodeling. Next, we inhibited calcineurin with cyclosporin A, but this also did not inhibit mitochondrial remodeling. These results indicate that mitochondrial remodeling under supraphysiological cyclic stretch is independent of Drp1 activation. In endothelial cells under supraphysiological cyclic stretch, reactive oxygen species (ROS) are generated. Mitochondrial morphologies are remodeled by ROS generation. When ROS was eliminated with N-acetyl-L-cysteine, mitochondrial remodeling was inhibited. Furthermore, when the polymerization of the actin cytoskeleton was inhibited with cytochalasin D, mitochondrial remodeling was also inhibited. These results suggest that ROS and actin cytoskeleton are rather involved in mitochondrial remodeling. In conclusion, the present results suggest that mitochondrial remodeling in endothelial cells under supraphysiological cyclic stretch is induced by ROS in association with actin cytoskeleton rather than through Drp1 activation.  相似文献   
995.
Furuichi  Tatsuya  Tsukamoto  Manami  Saito  Masaki  Sato  Yuriko  Oiji  Nobuyasu  Yagami  Kazuhiro  Fukumura  Ryutaro  Gondo  Yoichi  Guo  Long  Ikegawa  Shiro  Yamamori  Yu  Tomii  Kentaro 《Mammalian genome》2019,30(11):329-338

Cysteine-rich transmembrane bone morphogenetic protein regulator 1 (CRIM1) is a type I transmembrane protein involved in the organogenesis of many tissues via its interactions with growth factors including BMP, TGF-β, and VEGF. In this study, we used whole-exome sequencing and linkage analysis to identify a novel Crim1 mutant allele generated by ENU mutagenesis in mice. This allele is a missense mutation that causes a cysteine-to-serine substitution at position 140, and is referred to as Crim1C140S. In addition to the previously reported phenotypes in Crim1 mutants, Crim1C140S homozygous mice exhibited several novel phenotypes, including dwarfism, enlarged seminal vesicles, and rectal prolapse. In vitro analyses showed that Crim1C140S mutation affected the formation of CRIM1 complexes and decreased the amount of the overexpressed CRIM1 proteins in the cell culture supernatants. Cys140 is located in the internal region 1 (IR1) of the N-terminal extracellular region of CRIM1 and resides outside any identified functional domains. Inference of the domain architecture suggested that the Crim1C140S mutation disturbs an intramolecular disulfide bond in IR1, leading to the protein instability and the functional defects of CRIM1. Crim1C140S highlights the functional importance of the IR1, and Crim1C140S mice should serve as a valuable model for investigating the functions of CRIM1 that are unidentified as yet.

  相似文献   
996.
Cocculolidine isolated from leaves of Cocculus trilobus DC. (Kamiebi in Japanese), the host plant of Japanese fruit-piercing moths, exhibited insecticidal activity to leaf hoppers (Nephotettix bipunctatus cincticepts Uhler) and Azuki-been weevils (Callosobruchus chinensis Linne), however it had no activity to larvae of the fruit-piercing moth, Oraesia excavata Butler (Akaeguriba in Japanese), suggesting an interesting phenomenon of the host-parasite interrelationship.  相似文献   
997.
998.
The early growth of the Pacific tarpon,Megalops cyprinoides, was studied by larval otolith analysis and rearing of larvae and juveniles in the laboratory. Morphology of the sagitta, validation of sagittal daily increments, age at the start of metamorphosis, decrement of standard length in early metamorphosis, and growth under rearing conditions are described. The sagitta of fully-grown Pacific tarpon leptocephali were transparent and circular, with regular intervals between the neighboring rings becoming wider at the onset of metamorphosis. Alizarin complexone treatment of larvae confirmed the daily formation of the sagittal rings. Metamorphosis was estimated to start about one month after hatching. After drastic shrinkage during the first several days of metamorphosis, the body length more or less stabilized for one month and then resumed rapid growth. The early growth of Pacific tarpon was divided into four phases as follows: A) leptocephalus positive growth phase; B) leptocephalus negative growth phase; C) sluggish growth phase; and D) juvenile growth phase.  相似文献   
999.
The temperatures of the lipid phase transition at which the solid phase disappears were determined by using the X-ray diffraction method in thylakoid membranes of the blue-green alga, Anacystis nidulans. The temperatures were determined as 26 and 16°C for cells grown at 38 and 28°C, respectively.  相似文献   
1000.
Specific S-glycoproteins were isolated from three Brassica campestriscultivars homozygous with respect to the S-alleles S8, S9 andS12. Amino acid sequences of various peptide fragments of theS-proteins were determined using a gas-phase protein sequencer,and a nearly complete amino acid sequence of the S8-glycoproteinwas determined on the basis of the revised cDNA sequence ofthe B. oleracea S-specific glycoprotein. The lysyl endopeptidasefragments of S9 and S12-glycoproteins were aligned in comparisonwith the sequence of the S8-glycoprotein. Although extensivesequence homology was evident among the three S-glycoproteins,the sequences of the middle part were relatively different fromeach other. The numbers and positions of N-glycosylation alsodiffered among the S-glycoproteins of Brassica species. (Received April 20, 1987; Accepted July 29, 1987)  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号