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991.
Lee-Wei Chen Wei-Jung Chang Pei-Hsuan Chen Ching-Mei Hsu 《Journal of biomedical science》2010,17(1):48
Background
Major burn is associated with decreased gut barrier function and increased bacterial translocation (BT). This study is to investigate whether commensal microflora induce host defense and decrease BT in burn mice. 相似文献992.
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Recent studies indicated that alendronate enhanced osteogenesis in osteoblasts and human bone marrow-derived stem cells. However, the time- and dose-dependent effects of Aln on ostegenic differentiation and cytotoxicity of hBMSCs remain undefined. In present study, we investigated the effective dose range and timing of hBMSCs. hBMSCs were treated with various Aln doses (1, 5 and 10 µM) according to the following groups: group A was treated with Aln during the first five days of bone medium, groups B, C and D were treated during the first, second, and final five days of osteo-induction medium and group E was treated throughout the entire experiment. The mineralization level and cytotoxicity were measured by quantified Alizarin Red S staining and MTT assay. In addition, the reversal effects of farnesyl pyrophosphate and geranylgeranyl pyrophosphate replenishment in group B were also investigated. The results showed that Aln treatment in groups A, B and E enhanced hBMSC mineralization in a dose-dependent manner, and the most pronounced effects were observed in groups B and E. The higher dose of Aln simultaneously enhanced mineralization and caused cytotoxicity in groups B, C and E. Replenishment of FPP or GGPP resulted in partial or complete reverse of the Aln-induced mineralization respectively. Furthermore, the addition of FPP or GGPP also eliminated the Aln-induced cytotoxicity. We demonstrated that hBMSCs are susceptible to 5 µM Aln during the initiation stage of osteogenic differentiation and that a 10 µM dose is cytotoxic. 相似文献
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996.
Kuang-Hua Chen Sheng-Chi Hsu Hou-Yu Chen Kwai-Fong Ng Tse-Ching Chen 《Biochemical and biophysical research communications》2014
Discrimination between complete moles (CMs), partial moles (PMs), and hydropic abortions (HAs) is important as the risk of persistent gestational trophoblastic disease (GTD) differs for each condition. We evaluated whether ancillary fluorescence in situ hybridization (FISH) with a set of chromosome enumeration probes (CEP) for chromosomes X, Y, and 17 and p57 immunostaining could improve the clinical diagnosis. Forty-one products of conception (POC) were reclassified according to clinical performance, morphology, p57 immunostaining results, and FISH results. The accuracy of histological examination alone was 85% for the original diagnosis. FISH analysis showed diploidy in 19 of 20 CMs and triploidy in 4 of 6 PMs. The concordance rate was 92.5% on using the CEP probes. p57 Staining was negative in all CMs and positive in all PMs and HAs. Chromosomal abnormality was detected in 3 cases of HA by using FISH. In conclusion, combined p57 immunostaining and FISH with a set of 3 CEP probes for chromosomes X, Y, and 17 could be useful in the classification of hydatidiform moles. 相似文献
997.
Chih-Ming Liang Chun-Hsiung Hung Shu-Chuan Hsu Ing-Chih Yeh 《Applied microbiology and biotechnology》2010,86(2):709-719
This study investigates the diversity and the potential phosphorus-accumulating ability among the purple nonsulfur (PNS) bacteria.
Traditional methods and molecular biotechniques were applied. Microscopic visualization using 4′,6-diamidino-2-phenylindole
staining as well as chemical analysis demonstrated that most of the isolated PNS bacteria presented different levels of phosphorus
accumulation. Four of the pure cultures, denoted as Rhodopseudomonas palustris CC1, CC7, G11, and GE1, based on their differences in the PNS’s pufM gene, exhibited higher internal phosphorus content compared to other isolated strains in this study. In addition, substantial
polyphosphate accumulation was observed after the bacteria entered their stationary growth phase. Among them, the isolated
R. palustris G11 could accumulate internal phosphorus up to 13%–15% of its cell dry weight under anaerobic illuminated incubation conditions.
When the incubation status was switched from anaerobic to aerobic, the bacterial phosphorus content had a tendency to decrease
slightly or remain about the same throughout the whole aerobic stage. The growth rate and biomass were higher when the PNS
bacteria grew under photoheterotrophic conditions rather than the chemoheterotrophic ones. Furthermore, the environmental
pH value could affect the contents of internal bacterial phosphate. Results of this study demonstrated that PNS bacteria are
a group of the polyphosphate-accumulating organisms, of which this ability had never been properly studied. The conditions
that PNS bacteria accumulating polyphosphate presented from this study were unique and showed characteristics that were different
from the well-known enhanced biological phosphorus removal model. 相似文献
998.
X.-L. Chen † T.-Y. Chiang †‡ H.-D. Lin ‡ H.-S. Zheng K.-T. Shao § Q. Zhang K.-C. Hsu ‡¶ 《Journal of fish biology》2007,70(SA):75-93
Whole mitochondrial DNA cytochrome b sequences in 62 fish from 13 locations in Southeast China identified two major clades corresponding to two allopatric taxa, Glyptothorax fokiensis fokiensis and Glyptothorax fokiensis hainanensis . Reciprocal monophyly and a molecular clock separation between these two taxa of 2·3 million years indicate these taxa should be elevated to species. Mismatch distributions and Fu's F S statistic suggest that both G. fokiensis and G. hainanensis have experienced recent population expansions. Analysis of molecular variance indicates that most of the genetic variation resides among populations within both species, with Φ ST = 0·645 for G. fokiensis and 0·801 for G. hainanensis , suggesting restricted gene flow among populations. Significant correlations between the geographic and the genetic distances provide support for the importance of geographic isolations between populations. Nested clade analysis also confirms low levels of genetic exchanges between the two major groups and between populations within each group. The phylogeographical pattern among populations of Glyptothorax in East Asia can be attributed to historical fragmentations, demographic expansions and occasional long-distance dispersals stimulated by tectonic activity and Ice Age climate changes. 相似文献
999.
C-W Tsai F-J Lai H-M Sheu Y-S Lin T-H Chang M-S Jan S-M Chen P-C Hsu T-T Huang T-C Huang M-C Sheen S-T Chen W-C Chang N-S Chang L-J Hsu 《Cell death & disease》2013,4(9):e792
Squamous cell carcinoma (SCC) cells refractory to initial chemotherapy frequently develop disease relapse and distant metastasis. We show here that tumor suppressor WW domain-containing oxidoreductase (WWOX) (also named FOR or WOX1) regulates the susceptibility of SCC to methotrexate (MTX) in vitro and cure of SCC in MTX therapy. MTX increased WWOX expression, accompanied by caspase activation and apoptosis, in MTX-sensitive SCC cell lines and tumor biopsies. Suppression by a dominant-negative or small interfering RNA targeting WWOX blocked MTX-mediated cell death in sensitive SCC-15 cells that highly expressed WWOX. In stark contrast, SCC-9 cells expressed minimum amount of WWOX protein and resisted MTX-induced apoptosis. Transiently overexpressed WWOX sensitized SCC-9 cells to apoptosis by MTX. MTX significantly downregulated autophagy-related Beclin-1, Atg12–Atg5 and LC3-II protein expression and autophagosome formation in the sensitive SCC-15, whereas autophagy remained robust in the resistant SCC-9. Mechanistically, WWOX physically interacted with mammalian target of rapamycin (mTOR), which potentiated MTX-increased phosphorylation of mTOR and its downstream substrate p70 S6 kinase, along with dramatic downregulation of the aforementioned proteins in autophagy, in SCC-15. When WWOX was knocked down in SCC-15, MTX-induced mTOR signaling and autophagy inhibition were blocked. Thus, WWOX renders SCC cells susceptible to MTX-induced apoptosis by dampening autophagy, and the failure in inducing WWOX expression leads to chemotherapeutic drug resistance. 相似文献
1000.