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121.
The neurotransmitter dopamine and its dopamine receptor D2 (D2DR) agonists are known to inhibit vascular permeability factor/vascular endothelial growth factor (VEGF)-mediated angiogenesis and vascular permeability. Lung injury is a clinical syndrome associated with increased microvascular permeability. However, the effects of dopamine on pulmonary edema, a phenomenon critical to the pathophysiology of both acute and chronic lung injuries, have yet to be established. Therefore, we sought to determine the potential therapeutic effects of dopamine in a murine model of lipopolysaccharide (LPS)-induced acute lung injury (ALI). Compared with sham-treated controls, pretreatment with dopamine (50 mg/kg body wt) ameliorated LPS-mediated edema formation and lowered myeloperoxidase activity, a measure of neutrophil infiltration. Moreover, dopamine significantly increased survival rates of LPS-treated mice, from 0-75%. Mechanistically, we found that dopamine acts through the VEGF-VEGFR2 axis to reduce pulmonary edema, as dopamine pretreatment in LPS-treated mice resulted in decreased serum VEGF, VEGFR2 phosphorylation, and endothelial nitric oxide synthase phosphorylation. We used D2DR knockout mice to confirm that dopamine acts through D2DR to block vascular permeability in our lung injury model. As expected, a D2DR agonist failed to reduce pulmonary edema in D2DR(-/-) mice. Taken together, our results suggest that dopamine acts through D2DR to inhibit pulmonary edema-associated vascular permeability, which is mediated through VEGF-VEGFR2 signaling and conveys protective effects in an ALI model.  相似文献   
122.
A mixed-ligand ruthenium(III) catalyst complex, [RuIII(TDL*)(bipy)(H2O)]Cl (1) (TDL* = N-3,5-di-(t-butyl)salicylidine-d-glucosamine; bipy = 2,2′-bipyridine) exhibited catalytic activity toward enantioselective alkene epoxidation using tert-butyl hydroperoxide as terminal oxidant. Styrene, 4-chlorostyrene, 4-methylstyrene, 4-methoxystyrene, 1-methylcyclohexene and 1,2-dihydronaphthalene were effectively converted to their organic epoxides with moderate enantioselectivity (37-47% ee) at ambient temperature. A mechanism involving the formation of a high-valent Ru(V)-oxo species, and the subsequent oxo-transfer to the alkene through a metallaoxetane intermediate is proposed.  相似文献   
123.
124.
We consider the efficient estimation of a regression parameter in a partially linear additive nonparametric regression model from repeated measures data when the covariates are multivariate. To date, while there is some literature in the scalar covariate case, the problem has not been addressed in the multivariate additive model case. Ours represents a first contribution in this direction. As part of this work, we first describe the behavior of nonparametric estimators for additive models with repeated measures when the underlying model is not additive. These results are critical when one considers variants of the basic additive model. We apply them to the partially linear additive repeated-measures model, deriving an explicit consistent estimator of the parametric component; if the errors are in addition Gaussian, the estimator is semiparametric efficient. We also apply our basic methods to a unique testing problem that arises in genetic epidemiology; in combination with a projection argument we develop an efficient and easily computed testing scheme. Simulations and an empirical example from nutritional epidemiology illustrate our methods.  相似文献   
125.
Mesenchymal stromal cells (MSCs) are bone marrow-derived cells with multipotent differentiation capability that are mobilized into the circulation in response to injury and localize to areas of tissue damage including solid tumors. They have the capacity to adopt a phenotype similar to carcinoma-associated fibroblasts (CAFs) and, like CAFs, promote tumor growth. The molecular communication between tumor cells and MSCs has not been well defined. However, MSCs have increased expression of the chemokine stromal-derived factor 1 (SDF-1) when exposed to conditioned medium from tumor cells. Additionally, SDF-1 has been shown to be important in the promotion of tumor growth by CAFs. These data suggest that the SDF-1 signaling axis is a key feature of the tumor microenvironment. In this report, we demonstrate that interleukin 8 (IL-8) induces an increase in SDF-1 expression by MSCs. The increase in SDF-1 expression in response to IL-8 is mediated by the activation of the protein kinase C (PKC) zeta isoform. In a functional assay, activation of PKC is required for in vitro MSC migration in response to tumor conditioned medium. These results indicate that IL-8-mediated SDF-1 production by MSCs requires PKC zeta activation. This signaling pathway provides insight into possible molecular targets for cancer therapy aimed at disrupting the interaction between components of the tumor microenvironment.  相似文献   
126.
Sclerostin, a secreted glycoprotein, regulates osteoblast function. Using yeast two-hybrid and direct protein interaction analyses, we demonstrate that sclerostin binds the Wnt-modulating and Wnt-modulated, extracellular matrix protein, cysteine-rich protein 61 (Cyr61, CCN1), which regulates mesenchymal stem cell proliferation and differentiation, osteoblast and osteoclast function, and angiogenesis. Sclerostin was shown to inhibit Cyr61-mediated fibroblast attachment, and Cyr61 together with sclerostin increases vascular endothelial cell migration and increases osteoblast cell division. The data show that sclerostin binds to and influences the activity of Cyr61.  相似文献   
127.
We investigated the promoter polymorphisms of the pituitary growth hormone gene (GH1) and exon 3 deletion polymorphism (GHRd3) in its receptor gene (GHR) in 299 angiographically proven patients with coronary artery disease (CAD) and 231 asymptomatic controls enrolled in the ongoing Indian Atherosclerosis Research Study. Real time PCR based analysis of the GHR variant showed significant association of the GHRd3 deletion allele with CAD (OR 0.48, 95% CI: 0.30–0.76, P = 0.0014) and a dominant model of inheritance (Akaike information criterion = 482). The deletion allele showed significant association with high plasma HDL-c levels (P = 0.001). Sequencing of the proximal promoter region of GH1 revealed 12 novel polymorphisms and a TAGA haplotype constituted by the functional SNPs rs2005171, rs11568828, rs2005172 and rs6171, that showed significant association with CAD alone (adjusted OR of 3.31 (95% CI = 1.33–8.29, P = 0.011) and in CAD patients with diabetes (P = 0.019). Mean standardized height was associated with three of the four haplotype-tagging SNPs in the cohort (P ≤ 0.03). Eleven of the 12 polymorphic promoter SNPs contributed to 14.7% of variation in height in females in the whole dataset (P = 0.029). CAD patients with history of stroke exhibited marginally significantly lower mean height as compared to rest of the cohort (P < 0.006). In conclusion, genetic polymorphisms in the GHR gene and its ligand, GH1, may modulate the risk of CAD in the Asian Indian population.  相似文献   
128.
Plant responses are coordinately controlled by both external and internal signals. Apt perception of pathogen attack and its appropriate conversion to internal signals ultimately determine the outcome of innate immunity. The present review predicts the involvement of unconventional ‘guard/decoy model’ in chickpea-Fusarium encounter. Rapid alkalinization factor is predicted to act as initial ‘Gatekeeper decoy’ counteracting fungal entry. Phospholipases and cystatins probably function as ‘Guardees’ being shielded by R gene(s). Serine Threonine Kinases decodes external pathogenic signals to in planta defense alarms. 14.3.3 provides clues to the wilt mechanism. The versatile sugars serve as signal generators and transmitters maintaining intra and inter cellular connectivity during stress.Key words: R gene, decoy, guardee, RALF, ROS, STK, 14.3.3, sugar, defense‘Survival for existence’ is the dictum followed by the entire living world. Similarly ‘survival of the fittest’ is nature''s preference. Owing to the extensive surveillance system of higher organisms resistance becomes the natural rule while susceptibility the exception.1 All living entities are being exposed to a plethora of interactions ranging from mutualism to antagonism.2 However the adaptive strategies opted by the plants are unique, versatile and still grossly unknown which have attracted the researchers since decades towards looking into the varied responses and diversification of plant adaptation.Plants are hosts to a large number of organisms such as symbiotic/pathogenic bacteria, phytopathogenic fungi, harmful viruses and nematodes. All have their own stratagem to gain over their host.3 However only the plant-fungal interaction with Chickpea-Fusarium case study in particular, shall be the focal area of the present review. Fungi are classified as necrotrophic and biotrophic according to their nutritional requirements.4 Necrotrophs apply ‘brute force’ by killing host cells and thriving on their dead remains while biotrophs prefer subtler ‘modus operandi’—the stealth mechanism used to derive nutrients from live host cells.5 Irrespective of the pathogen type and their mode of nutrition procurement, perception of attack lies central to effective induction of innate immunity in plants.  相似文献   
129.
We report the first use of inorganic fluorescent lanthanide (europium and terbium) ortho phosphate [LnPO4·H2O, Ln = Eu and Tb] nanorods as a novel fluorescent label in cell biology. These nanorods, synthesized by the microwave technique, retain their fluorescent properties after internalization into human umbilical vein endothelial cells (HUVEC), 786-O cells, or renal carcinoma cells (RCC). The cellular internalization of these nanorods and their fluorescence properties were characterized by fluorescence spectroscopy (FS), differential interference contrast (DIC) microscopy, confocal microscopy, and transmission electron microscopy (TEM). At concentrations up to 50 μg/ml, the use of [3H]-thymidine incorporation assays, apoptosis assays (TUNEL), and trypan blue exclusion illustrated the non-toxic nature of these nanorods, a major advantage over traditional organic dyes  相似文献   
130.
Gene prioritization through genomic data fusion   总被引:4,自引:0,他引:4  
The identification of genes involved in health and disease remains a challenge. We describe a bioinformatics approach, together with a freely accessible, interactive and flexible software termed Endeavour, to prioritize candidate genes underlying biological processes or diseases, based on their similarity to known genes involved in these phenomena. Unlike previous approaches, ours generates distinct prioritizations for multiple heterogeneous data sources, which are then integrated, or fused, into a global ranking using order statistics. In addition, it offers the flexibility of including additional data sources. Validation of our approach revealed it was able to efficiently prioritize 627 genes in disease data sets and 76 genes in biological pathway sets, identify candidates of 16 mono- or polygenic diseases, and discover regulatory genes of myeloid differentiation. Furthermore, the approach identified a novel gene involved in craniofacial development from a 2-Mb chromosomal region, deleted in some patients with DiGeorge-like birth defects. The approach described here offers an alternative integrative method for gene discovery.  相似文献   
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