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51.
52.
KIT (c-kit oncogene product) pathway is constitutively activated in human testicular germ cell tumors 总被引:5,自引:0,他引:5
Nakai Y Nonomura N Oka D Shiba M Arai Y Nakayama M Inoue H Nishimura K Aozasa K Mizutani Y Miki T Okuyama A 《Biochemical and biophysical research communications》2005,337(1):289-296
We investigated the expression of KIT (product of c-kit oncogene), gain-of-function mutations, and activation of its downstream signal transduction in human testicular cancers. KIT was expressed in 88% (22/25) of seminomas and in 44.4% (4/9) of non-seminomas compared to adjacent normal testicular tissue. Nine of the KIT-expressing seminomas had mutations (40.9%; 9/22) in the c-kit gene; two cases in exon 11 and 7 cases in exon 17. Two of these mutations in exon 17 were novel, and the other seven mutations were identical to the already known gain-of-function mutations which cause activation of KIT without ligand stem cell factor. All of the mutant KIT and 53.8% (7/13) of wild-type KIT were phosphorylated (activated) and associated with phosphorylated phosphatidylinositol 3-kinase (PI3K). Akt was also phosphorylated in these seminomas, suggesting that the KIT-PI3K-Akt pathway is activated in seminoma. These findings suggest that the KIT-PI3K-Akt pathway is constitutively activated in testicular germ cell tumors, due to overexpression of KIT protein and/or gain-of-function mutations in the c-kit gene. 相似文献
53.
54.
Maruf Mohammad Akbor Koji Tomobe Tomomi Yamada Juhyon Kim Hiroki Mano Nobuyuki Kurosawa Kazuo Sasaki Yasuyuki Nomura Masaharu Isobe 《Biochemical and biophysical research communications》2013
The senescence-accelerated mouse prone 8 (SAMP8) strain exhibits age-related learning and memory deficits (LMD) at 2 months of age. Combined linkage analysis of 264 F2 intercross SAMP8 × JF1 mice and RNA-seq analysis identified Hcn1 gene out of 29 genes in the LMD region on chromosome 13. Hcn1 in SAMP8 strain showed 15 times less polyglutamine repetition compared to Japanese fancy mouse 1 (JF1). Whole cell patch clamp analysis showed that Hcn1 ion conductivity was significantly lower in SAMP8 compared to that of JF1, which may be associated with learning and memory deficiency. 相似文献
55.
In the tip-growing filamentous cell of the xanthophycean alga Vaucheria terrestris sensu Götz, a new growing tip develops in the non-growing, cylindrical region of the cell that was exposed by local illumination. The present study examined changes in the strength and extensibility of the cell wall of the new growing tip and in the matrix components of the inner surface of the cell wall. The internal pressure required to rupture the cell walls decreased remarkably during the early to middle stages of growing tip development, but the cell wall hardly extended before rupture. In contrast, during the middle and late stages of development, cell walls were extended by internal pressure. Atomic force microscopy revealed that protease-resistant, fine granular matrix components were present only at the apical portion of a normal growing tip, and were absent in the non-growing cylindrical region. In the early and middle stages of new growing tip development, these matrix components appeared in the cell walls in patches. These results suggest that first cell wall strength decreases and then cell wall extensibility increases in the development of new growing tips, and that protease-resistant, fine granular matrix components may be involved in rendering a cell wall extensible. 相似文献
56.
Kimi Araki Naoki Takeda Atsushi Yoshiki Yuichi Obata Naomi Nakagata Toshihiko Shiroishi Kazuo Moriwaki Ken-ichi Yamamura 《Mammalian genome》2009,20(1):14-20
MSM/Ms is an inbred mouse strain established from the Japanese wild mouse, Mus musculus molossinus, which has been phylogenetically distinct from common laboratory mouse strains for about 1 million years. The nucleotide
substitution rate between MSM/Ms and C57BL/6 is estimated to be 0.96%. MSM/Ms mice display unique characteristics not observed
in the commonly used laboratory strains, including an extremely low incidence of tumor development, high locomotor activity,
and resistance to high-fat-diet-induced diabetes. Thus, functional genomic analyses using MSM/Ms should provide a powerful
tool for the identification of novel phenotypes and gene functions. We report here the derivation of germline-competent embryonic
stem (ES) cell lines from MSM/Ms blastocysts, allowing genetic manipulation of the M. m. molossinus genome. Fifteen blastocysts were cultured in ES cell medium and three ES lines, Mol/MSM-1, -2, and -3, were established.
They were tested for germline competency by aggregation with ICR morulae and germline chimeras were obtained from all three
lines. We also injected Mol/MSM-1 ES cells into blastocysts of ICR or C57BL/6 × BDF1 mice and found that blastocyst injection
resulted in a higher production rate of chimeric mice than did aggregation. Furthermore, Mol/MSM-1 subclones electroporated
with a gene trap vector were also highly efficient at producing germline chimeras using C57BL/6 × BDF1 blastocyst injection.
This Mol/MSM-1 ES line should provide an excellent new tool allowing the genetic manipulation of the MSM/Ms genome. 相似文献
57.
Kazuo Hozumi 《Journal of plant research》1989,102(1):75-83
To gain a better understanding of growth curve, biomass duration in several growth models, such as the exponential, linear,
Gompertz, Mitscherlich, logistic, Richards and Bertalanffy, is formulated. Generally, biomass duration in these models can
be given in two ways; thet- andw-representations. The latter representation, which can be defined as the summed value of reciprocal of relative growth rate
with respect to biomass, gives a new significance to biomass duration. The utility of both representations is exemplified
by the observed data of a fir. The idea of biomass duration is extended to get total amounts of anabolism and catabolism in
the Bertalanffy model. 相似文献
58.
59.
Takashi Umeda Kazuo Saito Masashi Matsuzaka Shigeyuki Nakaji Manabu Totsuka Toshiki Okumura Toshiaki Tsukamoto Makoto Yaegaki Umi Kudoh Ippei Takahashi 《Luminescence》2008,23(3):115-120
In order to examine in detail the influence on the neutrophil immune function in sumo wrestlers of performing traditional and original training we examined changes in the neutrophil immune function in 17 male amateur university sumo wrestlers (aged 20.2 ± 1.5 years), before (‘Pre’) and after the training (‘Post’) for 2.5 h under fasting conditions. Assays included blood leukocyte and neutrophil counts, serum concentration of immunoglobulins, complements, myogenic enzymes and neutrophil oxidative burst activity (OBA) and phagocytic activity (PA). Myogenic enzymes, neutrophil counts, the ratio of neutrophil counts:leukocyte counts significantly increased and immunoglobulins and complements decreased in Post compared with Pre. There was a positive correlation between the change of neutrophil counts before and after the training and the change of creatine kinase (r = 0.667, p < 0.01). The Post OBA significantly increased and PA significantly decreased compared with Pre. It was concluded that sumo training causes muscular damage and an increase in the neutrophil count as a response. In this time, although OBA increased, PA decreased after training. Compensation between PA and reactive oxygen species production may exist to maintain the overall integrity of the neutrophil immune function. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
60.
Expression, purification, and crystallization of endopolygalacturonase from a pathogenic fungus, Stereum purpureum, in Escherichia coli 总被引:1,自引:0,他引:1
Shimizu T Shibata H Araya T Nakatsu T Miyairi K Okuno T Kato H 《Protein expression and purification》2005,44(2):558-135
Endopolygalacturonases (EC 3.2.1.15) catalyze random hydrolysis of the alpha-1,4 glycosidic linkages in polygalacturonic acid, a component of pectin. Previously, we reported crystal structures of endogenously produced Stereum purprureum endopolygalacturonase I (endoPG I), both in its native form and complexed with its product, galacturonate. However, the substrate-binding mechanism of endoPG I is still unclear, because crystals have not yet been obtained with a substrate analog, or with mutant enzymes that can bind substrates. We describe here an expression system using Escherichia coli and a purification method to prepare functionally active endoPG I for such mutation and crystallographic studies. Expression in E. coli strain Origami (DE3) provided a soluble and active enzyme with proper disulfide bond formation, whereas the enzyme expressed in BL21 (DE3) was localized in inclusion bodies. A sufficient amount of recombinant endoPG I produced by Origami (DE3) was purified by a single-step procedure using cation exchange chromatography. The specific activity of recombinant endoPG I was equivalent to that of the enzyme produced by S. purpureum. Recombinant endoPG I was crystallized under the same conditions as those used for the native enzyme produced by S. purpureum. The crystals diffracted beyond 1.0 A resolution with synchrotron radiation. 相似文献