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991.
Ruey-Hwang Chou Shu-Ching Hsieh Yung-Luen Yu Min-Hsien Huang Yi-Chang Huang Yi-Hsien Hsieh 《PloS one》2013,8(8)
Fisetin (3,3’,4’,7-tetrahydroxyflavone), a naturally occurring flavonoid, has been reported to inhibit proliferation and induce apoptosis in several cancer types. However, its effect on the anti-metastatic potential of cervical cancer cells remains unclear. In the present study, we found that fisetin inhibits the invasion and migration of cervical cancer cells. The expression and activity of urokinase plasminogen activator (uPA) was significantly suppressed by fisetin in a dose-dependent manner. We also demonstrated that fisetin reduces the phosphorylation of p38 MAPK, but not that of ERK1/2, JNK1/2, or AKT. Addition of a p38 MAPK inhibitor, SB203580, further enhanced the inhibitory effect of fisetin on the expression and activity of uPA and the invasion and motility in cervical cancer cells. Fisetin suppressed the TPA (tetradecanoylphorbol-13-acetate)-induced activation of p38 MAPK and uPA, and inhibited the TPA-enhanced migratory and invasive abilities. Furthermore, the promoter activity of the uPA gene was dramatically repressed by fisetin, which disrupted the nuclear translocation of NF-κB and its binding amount on the promoter of the uPA gene, and these suppressive effects could be further enhanced by SB203580. This study provides strong evidence for the molecular mechanism of fisetin in inhibiting the aggressive phenotypes by repression of uPA via interruption of p38 MAPK-dependent NF-κB signaling pathway in cervical cancer cells and thus contributes insight to the potential of using fisetin as a therapeutic strategy against cervical cancer by inhibiting migration and invasion. 相似文献
992.
993.
Andrew F. LoftusVivian L. Hsieh Raghuveer Parthasarathy 《Biochemical and biophysical research communications》2012,426(4):585-589
The sculpting of membranes into highly curved vesicles is central to intracellular cargo trafficking, yet the mechanical activities of trafficking proteins remain poorly understood. Using an optical trap based assay that measures in vitro membrane response to imposed deformations, we examined the behavior of the two human paralogs of Sar1, a key component of the COPII family of vesicle coat proteins. Like their yeast counterpart, the human Sar1 proteins can lower the mechanical rigidity of the membranes to which they bind. Unlike the yeast Sar1, the rigidity is not a monotonically decreasing function of concentration. At high concentrations, we find increased bending rigidity and decreased protein mobility. These features imply a model in which protein clustering governs membrane mechanical properties. 相似文献
994.
995.
Payungsuk Intawicha Shih-Han Wang Ya-Chen Hsieh Neng-Wen Lo Kun-Hsiung Lee San-Yuan Huang Jyh-Cherng Ju 《PloS one》2013,8(7)
Rabbit embryonic stem (rES) cells can be derived from various sources of embryos. However, understanding of the gene expression profile, which distincts embryonic stem (ES) cells from other cell types, is still extremely limited. In this study, we compared the protein profiles of three independent lines of rabbit cells, i.e., fibroblasts, fertilized embryo-derived stem (f-rES) cells, and parthenote-derived ES (p-rES) cells. Proteomic analyses were performed using two-dimensional gel electrophoresis (2-DE) and mass spectrometry. Collectively, the expression levels of 100 out of 284 protein spots differed significantly among these three cell types (p<0.05). Of those differentially expressed spots, 91% were identified in the protein database and represented 63 distinct proteins. Proteins with known identities are mainly localized in the cytoplasmic compartments (48%), nucleus (14%), and cytoskeletal machineries (13%). These proteins were majorly involved in biological functions of energy and metabolic pathways (25%), cell growth and maintenance (25%), signal transduction (14%), and protein metabolisms (10%). When protein expression levels among cell types were compared, six proteins associated with a variety of cellular activities, including structural constituents of the cytoskeleton (tubulins), structural molecule (KRT8), catalytic molecules (α-enolase), receptor complex scaffold (14-3-3 protein sigma), microfilament motor proteins (Myosin-9), and heat shock protein (HSP60), were found highly expressed in p-rES cells. Two proteins related to HSP activity and structural constituent of cytoskeleton in f-rES cells, and one structural molecule activity protein in fibroblasts showed significantly higher expression levels (p<0.05). Marker protein expressions in f-rES and p-rES cells were further confirmed by Western blotting and immunocytochemical staining. This study demonstrated unique proteomic profiles of the three rabbit cell types and revealed some novel proteins differentially expressed between f-rES and p-rES cells. These analyses provide insights into rES cell biology and would invite more in-depth studies toward rES cell applications. 相似文献
996.
The inflence of household type on reproductive behavior is examined for a national probability sample of Taiwanese women. Data were derived from a 1980 national household survey of the labor force in Taiwan, focusing on 10,624 couples. Reproductive variables include measures of current and prospective fertility as well as cumulative fertility. In spite of remarkable social and economic development over the past 3 decades, extended families are still widely found in Taiwan. Women in extended households have only slightly higher fertility preferences and current fertility than women in nuclear families once marital duration is controlled. Although women in extended households marry earlier and receive more family help with child care than women in nuclear families, such factors are no longer considered sufficient to produce major differentials in reproductive behavior. Residence and husband's class of work are the strongest correlates of whether a household is currently extended or nuclear. In general, the husband's characteristics are more strongly related to family type than the wife's. Findings suggest that preferences for smaller families and low fertility need not await a transformation to a nuclear family structue. 相似文献
997.
998.
Wen-Hsiung Ko Yi-Jung Tsou Yu-Ming Ju Huei-Mei Hsieh Pao-Jen Ann 《Mycopathologia》2010,169(2):125-131
Four fungal isolates that were able to use vegetable tissues for multiplication in soil were isolated and identified as Pseudallescheria boydii based on morphological characteristics and ITS sequence similarity. When grown in broth prepared from the same vegetable
tissues used in soil amendment, all these isolates of P. boydii produced a substance capable of reducing the disease incidence of black leaf spot of spoon cabbage caused by Alternaria brassicicola and inhibiting the germination of A. brassicicola conidia. The substance, which was fungistatic, was very stable under high temperature and high or low pH value. It was soluble
in polar solvents and insoluble in non-polar solvents. Molecular weight estimation and ion exchange ability tests suggest
that the fungistatic compound has a molecular weight between 500 and 1,000 and has no charge on its molecule. Results from
this study suggest the possession of a strong competitive saprophytic ability by P. boydii, which in turn may explain the widespread occurrence of this human pathogen in soil. Production of a fungistatic substance
when P. boydii was grown in broth prepared from vegetable tissues suggests the importance of antibiotic production in its competitive saprophytic
colonization of organic matters in soil. 相似文献
999.
Ho-Chang Kuo Yu-Wen Hsu Chung-Min Wu Shawn Hsiang-Yin Chen Kuo-Sheng Hung Wei-Pin Chang Kuender D. Yang Kai-Sheng Hsieh Wei-Chiao Chen Yoshihiro Onouchi Wei-Chiao Chang 《PloS one》2013,8(7)
Single-nucleotide polymorphisms (SNPs) in inositol 1,4,5-trisphosphate 3-kinase C (ITPKC, rs28493229) and caspase-3 (CASP3, rs113420705) are associated with susceptibility to KD in Japanese and Taiwanese populations. This study was conducted to investigate the involvement of these 2 SNPs in the risk for intravenous immunoglobulin (IVIG) resistance and coronary artery lesion (CAL) in Taiwanese population. A total of 340 KD patients were subjected to assess by the identification of 2-locus genes model. A combinatorial association between ITPKC (rs28493229) and CASP3 (rs113420705) was found in CAL formation (P = 0.0227, OR: 3.06). KD patients with high-risk genotype had a trend of overrepresentation in IVIG resistance compared with individual SNPs. Our findings suggest the existence of genetic factors affecting patients’ risk for CAL formation and IVIG responsiveness in a Taiwanese population. 相似文献
1000.