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991.
Ciliopathies are a group of hereditary disorders associated with defects in cilia structure and function. The distal appendages (DAPs) of centrioles are involved in the docking and anchoring of the mother centriole to the cellular membrane during ciliogenesis. The molecular composition of DAPs was recently elucidated and mutations in two genes encoding DAPs components (CEP164/NPHP15, SCLT1) have been associated with human ciliopathies, namely nephronophthisis and orofaciodigital syndrome. To identify additional DAP components defective in ciliopathies, we independently performed targeted exon sequencing of 1,221 genes associated with cilia and 5 known DAP protein-encoding genes in 1,255 individuals with a nephronophthisis-related ciliopathy. We thereby detected biallelic mutations in a key component of DAP-encoding gene, CEP83, in seven families. All affected individuals had early-onset nephronophthisis and four out of eight displayed learning disability and/or hydrocephalus. Fibroblasts and tubular renal cells from affected individuals showed an altered DAP composition and ciliary defects. In summary, we have identified mutations in CEP83, another DAP-component-encoding gene, as a cause of infantile nephronophthisis associated with central nervous system abnormalities in half of the individuals.  相似文献   
992.
We studied centrifugation-mediated mechanical stress-induced tumor necrosis factor-alpha (TNF-alpha) production in the monocyte-like cell line THP-1. The induction of TNF-alpha by mechanical stress was dependent on the centrifugation speed and produced the highest level of TNF-alpha after 1 h of stimulation. TNF-alpha production returned to normal levels after 24 h of stimulation. Mechanical stress also induced Toll-like receptor-2 (TLR2) mRNA in proportion to the expression of TNF-alpha. The inhibition of TLR2 signaling by dominant negative myeloid differentiation factor 88 (MyD88) blocked TNF-alpha expression response to mechanical stress. After transient overexpression of TLR2 in HEK-293 cells, mechanical stress induced TNF-alpha mRNA production. Interestingly, mechanical stress activated the c-Src-dependent TLR2 phosphorylation, which is necessary to induce Ca(2+) fluxes. When THP-1 cells were pretreated with BAPTA-AM, thapsigargin, and NiCl(2).6H(2)O, followed by mechanical stimulation, both TLR2 and TNF-alpha production were inhibited, indicating that centrifugation-mediated mechanical stress induces both TLR2 and TNF-alpha production through Ca(2+) releases from intracellular Ca(2+) stores following TLR2 phosphorylation. In addition, TNF-alpha treatment in THP-1 cells induced TLR2 production in response to mechanical stress, whereas the preincubation of anti-TNF-alpha antibody scarcely induced the mechanical stress-mediated production of TLR2, indicating that TNF-alpha produced by mechanically stimulated THP-1 cells affected TLR2 production. We concluded that TNF-alpha production induced by centrifugation-mediated mechanical stress is dependent on MyD88-dependent TLR2 signaling that is associated with Ca(2+) release and that TNF-alpha production induced by mechanical stress affects TLR2 production.  相似文献   
993.
TLRs can activate two distinct branches of downstream signaling pathways. MyD88 and Toll/IL-1R domain-containing adaptor inducing IFN-beta (TRIF) pathways lead to the expression of proinflammatory cytokines and type I IFN genes, respectively. Numerous reports have demonstrated that resveratrol, a phytoalexin with anti-inflammatory effects, inhibits NF-kappaB activation and other downstream signaling pathways leading to the suppression of target gene expression. However, the direct targets of resveratrol have not been identified. In this study, we attempted to identify the molecular target for resveratrol in TLR-mediated signaling pathways. Resveratrol suppressed NF-kappaB activation and cyclooxygenase-2 expression in RAW264.7 cells following TLR3 and TLR4 stimulation, but not TLR2 or TLR9. Further, resveratrol inhibited NF-kappaB activation induced by TRIF, but not by MyD88. The activation of IFN regulatory factor 3 and the expression of IFN-beta induced by LPS, poly(I:C), or TRIF were also suppressed by resveratrol. The suppressive effect of resveratrol on LPS-induced NF-kappaB activation was abolished in TRIF-deficient mouse embryonic fibroblasts, whereas LPS-induced degradation of IkappaBalpha and expression of cyclooxygenase-2 and inducible NO synthase were still inhibited in MyD88-deficient macrophages. Furthermore, resveratrol inhibited the kinase activity of TANK-binding kinase 1 and the NF-kappaB activation induced by RIP1 in RAW264.7 cells. Together, these results demonstrate that resveratrol specifically inhibits TRIF signaling in the TLR3 and TLR4 pathway by targeting TANK-binding kinase 1 and RIP1 in TRIF complex. The results raise the possibility that certain dietary phytochemicals can modulate TLR-derived signaling and inflammatory target gene expression and can alter susceptibility to microbial infection and chronic inflammatory diseases.  相似文献   
994.
Egg production rate (EPR) of the copepod Acartia steueri wasinvestigated by in situ incubation in Ilkwang Bay, Korea. EPRranged from 3.8 to 10.1 eggs female–1 d–1, and weight-specificgrowth rate decreased with increasing body weight of the adultfemale.  相似文献   
995.
Summary Expression of human IL-2 from the cDNA and synthetic gene was compared using theE. coli expression system. Expression plasmids containing the cDNA or synthetic gene in which the only difference was the coding sequences were constructed. Expression of IL-2 from the cDNA and synthetic gene were estimated to be as high as 18% and 14%, respectively. No correlation was found between the major codon bias and high level expression of IL-2 in this system.  相似文献   
996.
997.
Molecular Biology Reports - Colorectal cancer (CRC) is one of the most common cancers, and rates of incidence and diagnosis of CRC have gradually increased. Carcinoembryonic antigen (CEA) is...  相似文献   
998.
In this paper, we investigate K‐group comparisons on survival endpoints for observational studies. In clinical databases for observational studies, treatment for patients are chosen with probabilities varying depending on their baseline characteristics. This often results in noncomparable treatment groups because of imbalance in baseline characteristics of patients among treatment groups. In order to overcome this issue, we conduct propensity analysis and match the subjects with similar propensity scores across treatment groups or compare weighted group means (or weighted survival curves for censored outcome variables) using the inverse probability weighting (IPW). To this end, multinomial logistic regression has been a popular propensity analysis method to estimate the weights. We propose to use decision tree method as an alternative propensity analysis due to its simplicity and robustness. We also propose IPW rank statistics, called Dunnett‐type test and ANOVA‐type test, to compare 3 or more treatment groups on survival endpoints. Using simulations, we evaluate the finite sample performance of the weighted rank statistics combined with these propensity analysis methods. We demonstrate these methods with a real data example. The IPW method also allows us for unbiased estimation of population parameters of each treatment group. In this paper, we limit our discussions to survival outcomes, but all the methods can be easily modified for any type of outcomes, such as binary or continuous variables.  相似文献   
999.
Measures of biodiversity are often hindered by a lack of methodological practices that distinguish cryptic or morphologically similar cohabiting species. This is particularly difficult for marine fishes where direct observations of the ecology and demography of populations are difficult. Dragonets (Foetorepus c.f. calauropomus) were collected as bycatch from research trawls deployed in waters off north-eastern Tasmania, Australia. Morphometric and genetic analyses were conducted on the 43 specimens recovered. Sequence analysis of two mitochondrial loci distinguished three genetic clusters, each having levels of dissimilarity consistent with species-level distinctions between other members of the Callionymidae. While clear morphological distinctions were observed between male and female fish, limited morphometric analyses could not differentiate between members of the three genetic groups. This finding highlights questions about the ability of genetically distinct but morphologically similar groups to occupy the same ecological niche, and points to additional and undescribed hidden biodiversity amongst cryptic species of fish.  相似文献   
1000.
Intestinal organoids have recently emerged as an in vitro model relevant to the gut system owing to their recapitulation of the native intestinal epithelium with crypt–villus architecture. However, it is unclear whether intestinal organoids reflect the physiology of the in vivo stress response. Here, we systemically investigated the radiation response in organoids and animal models using mesenchymal stem cell-conditioned medium (MSC-CM), which contains secreted paracrine factors. Irradiated organoids exhibited sequential induction of viability loss and regrowth after irradiation (within 12 days), similar to the response of the native intestinal epithelium. Notably, treatment with MSC-CM facilitated the reproliferation of intestinal stem cells (ISCs) and restoration of damaged crypt-villus structures in both models. Furthermore, Wnt/Notch signaling pathways were commonly upregulated by MSC-CM, but not radiation, and pharmacologically selective inhibition of Wnt or Notch signaling attenuated the enhanced recovery of irradiated organoids, with increases in ISCs, following MSC-CM treatment. Interestingly, the expression of Wnt4, Wnt7a, and active β-catenin was increased, but not notch family members, in MSC-CM-treated organoid after irradiation. Treatment of recombinant mouse Wnt4 and Wnt7a after irradiation improved to some extent intestinal epithelial regeneration both in vitro and in vivo. Overall, these results suggested that intestinal organoids recapitulated the physiological stress response of the intestinal epithelium in vivo. Thus, our findings provided important insights into the physiology of intestinal organoids and may contribute to the development of strategies to enhance the functional maturation of engineered organoids.  相似文献   
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