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121.
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J G Kang M S Paget Y J Seok M Y Hahn J B Bae J S Hahn C Kleanthous M J Buttner J H Roe 《The EMBO journal》1999,18(15):4292-4298
124.
Kim EK Tucker DF Yun SJ Do KH Kim MS Kim JH Kim CD Birnbaum MJ Bae SS 《Cellular signalling》2008,20(11):2030-2037
The phosphatidylinositol 3-kinase (PI3K) signaling pathway(s) is activated by a variety of agonists to regulate cell migration. Here, we show that the stimulation of mouse embryonic fibroblasts with platelet-derived growth factor (PDGF) induces migration in a PI3K-dependent manner. Cells lacking Akt1/PKBalpha exhibit impaired migration and peripheral ruffling in response to PDGF stimulation, whereas cells lacking Akt2/PKBbeta are normal. In addition, over-expression of Akt1/PKBalpha but not Akt2/PKBbeta is sufficient to restore PDGF-induced cell migration in an Akt1/PKBalpha and Akt2/PKBbeta deficient background. In response to PDGF stimulation, Akt1/PKBalpha selectively translocates to membrane ruffles, however, this localization is abrogated by substituting the linker region of Akt2/PKBbeta. Similarly, expression of an Akt2/PKBalpha chimera containing the linker region of Akt1/PKBalpha restored PDGF-induced migration in cells lacking both Akt1/PKBalpha and Akt2/PKBbeta. Finally, over-expression of constitutively active Rac rescues PDGF-induced migration defects in cells lacking Akt1/PKBalpha. Given these results, we suggest that Akt1/PKBalpha controls cell migration by selectively translocating to the leading edge and activating Rac. 相似文献
125.
Khoshnan A Tindell C Laux I Bae D Bennett B Nel AE 《Journal of immunology (Baltimore, Md. : 1950)》2000,165(4):1743-1754
We explored the role of the NF-kappa B pathway in the survival of primary human CD4+ T lymphocytes during CD28 costimulation. Transduction of proliferating CD4+ T cells with a tetracycline-regulated retrovirus encoding for a dominant-interfering, degradation-resistant I-kappaBalpha (inhibitor of kappa B alpha factor) mutant induced apoptosis. Using DNA arrays, we show that Bcl-xL features as a prominent anti-apoptotic member among a number of early CD28-inducible genes. A 1.2-kb segment of the proximal Bcl-xL promoter, linked to a luciferase reporter, responded to CD3/CD28 stimulation in Jurkat cells. Mutation of an NF-kappa B site around -840 decreased, while ectopic expression of I-kappa B kinase-beta (IKK beta) enhanced reporter gene activity. Na+-salicylate and cyclopentenone PGs, direct inhibitors of IKK beta, interfered in the activation of the Bcl-xL promoter and induced apoptosis in CD28-costimulated CD4+ T cells. Moreover, salicylate blocked nuclear localization of NF-kappa B factors that bind to the NF-kappa B binding site in the Bcl-xL promoter, as well as the expression of Bcl-xL protein. HuT-78, a lymphoblastoid T cell line with constitutive NF-kappa B activity, contained elevated levels of Bcl-xL protein and, similar to proliferating CD4+ T cells, was resistant to apoptotic stimuli such as anti-Fas and TNF-alpha. In contrast, the same stimuli readily induced apoptosis in a Jurkat T cell clone with no detectable Bcl-xL expression. Jurkat BMS2 cells also differed from HuT-78 in collapse of mitochondrial membrane potential and superoxide generation in the mitochondrium. Taken together, these data demonstrate that CD3/CD28-induced activation of IKK beta and expression of Bcl-xL promote the survival of primary human CD4+ T lymphocytes. 相似文献
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127.
JS Goo MK Jang SB Shim SW Jee SH Lee CJ Bae S Park KJ Kim JE Kim IS Hwang HR Lee SI Choi YJ Lee CJ Lim DY Hwang 《Laboratory animal research》2012,28(2):141-145
The drug resistance of microorganisms isolated from laboratory animals never treated with antibiotics is being reported consistently, while the number of laboratory animals used in medicine, pharmacy, veterinary medicine, agriculture, nutrition, and environmental and health science has increased rapidly in Korea. Therefore, this study examined the development of antimicrobial resistance in bacteria isolated from laboratory animals bred in Korea. A total of 443 isolates (7 species) containing 5 Sphingomonas paucimobilis, 206 Escherichia coli, 60 Staphylococcus aureus, 15 Staphylococcus epidermidis, 77 Enterococcus faecalis, 27 Citrobacter freundii, 35 Acinetobacter baumannii were collected from the nose, intestine, bronchus and reproductive organs of ICR mice and SD rats. Of these species, Acinetobacter baumannii and Enterococcus faecalis showed significant antimicrobial resistance according to the minimum inhibition concentration (MIC) in E-test. In case of Acinetobacter baumannii, several isolates showed MIC values 16-128 μg/mL for cefazolin and cefoxitin, and higher resistance (128-512 μg/mL) to nitrofurantoin than that of standard type. Resistance to cefazolin, cefoxitin and nitrofurantoin was detected in 17.14, 20.00, and 8.57% of the Acinetobacter baumannii isolates, respectively. In addition, 44.1% of the Enterococcus faecalis isolates collected from the laboratory animals were resistant to oxacillin concentration of 16-32 μg/mL range, while MIC value of standard type was below oxacillin concentration of 6 μg/mL. These results suggest that in rodent species of laboratory animals, Acinetobacter baumannii are resistance to cefazolin, cefoxitin and nitrofurantoin, whereas those of Enterococcus faecalis were resistance to oxacillin. 相似文献
128.
The attractiveness of live adult stink bugs used as baits in traps in soybean fields, Milyang, Korea, to conspecific stink bugs was evaluated. Both sexes of bean bug, Riptortus pedestris Fabricius (Hemiptera: Alididae), and one-banded stink bug, Piezodorus hybneri Gmelin (Hemiptera: Pentatomidae), were attracted to conspecific male adults-baited traps. Likewise, both sexes of brown-marmorated stink bug, Halyomorpha halys Stål (Hemiptera: Pentatomidae), and sole bug, Dolycoris baccarum L. (Hemiptera: Pentatomidae), were attracted to traps baited with conspecific male stink bugs. However, in Nezara antennata Scott (Hemiptera: Pentatomidae), both male and female used as baits in traps were attractive to conspecific adults. Accordingly, these results suggest that the only male adults of H. halys and D. baccarum and both sexes of N. antennata are attractive to conspecific male stink bugs. 相似文献
129.
Amyotrophic lateral sclerosis (ALS) is the most common adult onset motor neuron disease. The etiology and pathogenic mechanisms of the disease remain unknown, and there is no effective treatment. Here we show that intrathecal transplantation of human motor neurons derived from neural stem cells (NSCs) in spinal cord of the SOD1G93A mouse ALS model delayed disease onset and extended life span of the animals. When HB1.F3.Olig2 (F3.Olig2) cells, stable immortalized human NSCs encoding the human Olig2 gene, were treated with sonic hedgehog (Shh) protein for 5–7 days, the cells expressed motor neuron cell type-specific phenotypes Hb9, Isl-1 and choline acetyltransferase (ChAT). These F3.Olig2-Shh human motor neurons were transplanted intrathecally in L5–L6 spinal cord of SOD1G93A mice, and at 4 weeks post-transplantation, transplanted F3.Olig2-Shh motor neurons expressing the neuronal phenotype markers NF, MAP2, Hb9, and ChAT were found in the ventral horn of the spinal cord. Onset of clinical signs in ALS mice with F3.Olig2-Shh motor neuron implants was delayed for 7 days and life span of animals was significantly extended by 20 days. Our results indicate that this treatment modality of intrathecal transplantation of human motor neurons derived from NSCs might be of value in the treatment of ALS patients without significant adverse effects. 相似文献
130.
Hansol Bae Soo Min Choi Seong Wook Yang Hyun-Sook Pai Woo Taek Kim 《Molecules and cells》2009,28(1):57-65
CDC48 is a member of the AAA ATPase superfamily. Yeast CDC48 and its mammalian homolog p97 are implicated in diverse cellular
processes, including mitosis, membrane fusion, and ubiquitin-dependent protein degradation. However, the cellular functions
of plant CDC48 proteins are largely unknown. In the present study, we performed virus-induced gene silencing (VIGS) screening
and found that silencing of a gene encoding a tobacco CDC48 homolog, NgCDC48, resulted in severe abnormalities in leaf and
shoot development in tobacco. Furthermore, transgenic tobacco plants (35S:anti-NgCDC48), in which the NgCDC48 gene was suppressed using the antisense RNA method, exhibited severely aberrant development of both vegetative and reproductive
organs, resulting in arrested shoot and leaf growth and sterile flowers. Approximately 57–83% of 35S:anti-NgCDC48 plants failed to develop mature organs and died at early stage of development. Scanning electron microscopy showed that both
adaxial and abaxial epidermal pavement cells in antisense transgenic leaves were significantly smaller and more numerous than
those in wild type leaves. These results indicate that NgCDC48 is critically involved in cell growth and development of tobacco
plants. An in vivo targeting experiment revealed that NgCDC48 resides in the endoplasmic reticulum (ER) in tobacco protoplasts. We consider
the tantalizing possibility that CDC48-mediated degradation of an as-yet unidentified protein(s) in the ER might be a critical
step for cell growth and expansion in tobacco leaves. 相似文献