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991.
Expression of multiple drug resistant (MDR) phenotype and over-expression of P-glycoprotein (P-gp) in the human hepatocellular carcinoma (HCC) cell clone P1(0.5), derived from the PLC/PRF/5 cell line (P5), are associated with strong resistance to oxidative stress and a significant (?p<0.01) increase in intracellular vitamin E content as compared with the parental cell line. This study evaluates the role of vitamin E in conferring resistance to drugs and oxidative stress in P1(0.5) cells. Parental drug-sensitive cells, P5, were incubated in α-tocopherol succinate (α-TS, 5?μM for 24?h) enriched medium to increase intracellular vitamin E content to levels comparable to those observed in P1(0.5) cells at basal conditions. Susceptibility to lipid peroxidation and oxidative DNA damage were assessed by measuring the concentration of thiobarbituric-reactive substances (TBARS) and 8-hydroxy-2′-deoxyguanosine (8-OHdG) at basal and after experimental conditions. Cell capacity to form colonies and resistance to doxorubicin were also studied. P5 cells, treated with α-TS, became resistant to ADP-Fe3+ and to ionizing radiation-induced lipid peroxidation as P1(0.5) cells. Exposure to ADP-Fe3+ or ionizing radiation increased TBARS and the 8-OHdG content in the P5 cells, while vitamin E enrichment abolished these effects. Irradiation doses at 5?cGy increased TBARS and 8-OHdG. They also inhibited cell capacity to form colonies in the untreated P5 cells. Incubation with α-TS fully reverted this effect and significantly (p<0.01) reduced the inhibitory effect of cell proliferation induced by irradiation doses at >500?cGy. Resistance to doxorubicin was not affected by α-TS. These observations demonstrate the role of vitamin E in conferring protection from lipid peroxidation, ionizing radiation and oxidative DNA damage on the human HCC cell line. They also rule out any role of P-gp over-expression as being responsible for these observations in cells with MDR phenotype expression.  相似文献   
992.
The need for comprehensive and reliable risk management of chemicals requires appropriate information, data integration, and sharing, as suggested in Europe by Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) regulation. REACH requires more sharing of responsibilities among authorities, chemical manufacturers, importers, and users to manage the risks that chemicals can pose to human health and the environment throughout their life cycle. This has obviously enlarged the audience of people who could be interested in gathering this information. A major bottleneck is that information sources on chemicals are frequently sparsely distributed, collected, and managed by different institutions, with different aims, resulting in several practical problems. This article describes the conceptual design and implementation of a free online access database (DESC) as an integrated information system on chemical substances in compliance with the REACH regulation. An interdisciplinary approach was applied by involving several experts from different disciplines (ecotoxicologists, chemists, information technology specialists, regulators). DESC contains relevant environmental and toxicological data (physico-chemical and ecotoxicological data, inclusion in priority lists, current classification and labeling, etc.) on more than 651 chemicals, which can be easily consulted by people with different degrees of expertise interested in knowing the risk from exposure to chemicals and their safe use.  相似文献   
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Bovine herpesvirus type 4 (BoHV‐4), like other herpesviruses, induces a series of alterations in the host cell that modify the intracellular environment in favor of viral replication, survival and spread. This research examined the impact of BoHV‐4 infection on autophagy in BoHV‐4 infected Madin Darby bovine kidney (MDBK) cells. Protein extracts of BoHV‐4 infected and control MDBK cells were subjected to Western blot. The concentrations of the autophagy and apoptosis‐related proteins Beclin 1, p21, PI3 kinase, Akt1/2, mTOR, phospho mTOR, p62 and the light chain three (LC3) were normalized to the actin level and expressed as the densitometric ratio. Western blot analysis of virus‐infected cells revealed that autophagic degradation pathway was induced in the late phase of BoHV‐4 infection. After 48 h post‐infection the protein LC3II, which is essential for autophagy was found to be markedly increased, while infection of MDBK cells with BoHV‐4 resulted in a depletion of p62 levels. Becline 1, PI3 kinase, Akt1/2 and p21 expression increased between 24 and 48 h post‐infection. Surprisingly, mTOR and its phosphorylated form, which are negative regulators of autophagy, also increased after 24 h post‐infection. In conclusion, our findings suggest that BoHV‐4 has developed mechanisms for modulation of autophagy that are probably part of a strategy designed to enhance viral replication and to evade the immune system. Additional studies on the relationship between autophagy and BoHV‐4 replication and survival, in both lytic and latent replication phases, are needed to understand the role of autophagy in BoHV‐4 pathogenesis. J. Cell. Biochem. 114: 1529–1535, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
996.

Background

A clinical heterogeneity was reported in patients with Cystic Fibrosis (CF) with the same CFTR genotype and between siblings with CF.

Methods

We investigated all clinical aspects in a cohort of 101 pairs of siblings with CF (including 6 triplets) followed since diagnosis.

Results

Severe lung disease had a 22.2% concordance in sib-pairs, occurred early and the FEV1% at 12?years was predictive of the severity of lung disease in the adulthood. Similarly, CF liver disease occurred early (median: 15?years) and showed a concordance of 27.8% in sib-pairs suggesting a scarce contribution of genetic factors; in fact, only 2/15 patients with liver disease in discordant sib-pairs had a deficiency of alpha-1-antitrypsin (a known modifier gene of CF liver phenotype). CF related diabetes was found in 22 pairs (in 6 in both the siblings). It occurred later (median: 32.5?years) and is strongly associated with liver disease. Colonization by P. aeruginosa and nasal polyposis that required surgery had a concordance >?50% in sib-pairs and were poorly correlated to other clinical parameters. The pancreatic status was highly concordant in pairs of siblings (i.e., 95.1%) but a different pancreatic status was observed in patients with the same CFTR mutations. This suggests a close relationship of the pancreatic status with the “whole” CFTR genotype, including mutations in regulatory regions that may modulate the levels of CFTR expression. Finally, a severe course of CF was evident in a number of patients with pancreatic sufficiency.

Conclusions

Physicians involved in care of patients with CF and in genetic counseling must be aware of the clinical heterogeneity of CF even in sib-pairs that, at the state of the art, is difficult to explain.
  相似文献   
997.
Inflammation and ageing are intertwined in chronic obstructive pulmonary disease (COPD). The histone deacetylase SIRT1 and the related activation of FoxO3 protect from ageing and regulate inflammation. The role of SIRT1/FoxO3 in COPD is largely unknown. This study evaluated whether cigarette smoke, by modulating the SIRT1/FoxO3 axis, affects airway epithelial pro‐inflammatory responses. Human bronchial epithelial cells (16HBE) and primary bronchial epithelial cells (PBECs) from COPD patients and controls were treated with/without cigarette smoke extract (CSE), Sirtinol or FoxO3 siRNA. SIRT1, FoxO3 and NF‐κB nuclear accumulation, SIRT1 deacetylase activity, IL‐8 and CCL20 expression/release and the release of 12 cytokines, neutrophil and lymphocyte chemotaxis were assessed. In PBECs, the constitutive FoxO3 expression was lower in patients with COPD than in controls. Furthermore, CSE reduced FoxO3 expression only in PBECs from controls. In 16HBE, CSE decreased SIRT1 activity and nuclear expression, enhanced NF‐κB binding to the IL‐8 gene promoter thus increasing IL‐8 expression, decreased CCL20 expression, increased the neutrophil chemotaxis and decreased lymphocyte chemotaxis. Similarly, SIRT1 inhibition reduced FoxO3 expression and increased nuclear NF‐κB. FoxO3 siRNA treatment increased IL‐8 and decreased CCL20 expression in 16HBE. In conclusion, CSE impairs the function of SIRT1/FoxO3 axis in bronchial epithelium, dysregulating NF‐κB activity and inducing pro‐inflammatory responses.  相似文献   
998.
Faro Lake is a coastal meromictic lagoon with singular characteristics in the Mediterranean (Messina, Sicily – Italy). It is part of the Natural Oriented Reserve of Capo Peloro (38° 15′ 57″ N; 15° 37′ 50″ E). In this area, traditional mollusc farming activity persists, producing ‘autochthonous’ mussels. This study reports of the Mytilus galloprovincialis haemolymph chemical profile and water variables determination of 1 year‐lasted survey (April 2016 – March 2017). The determinations of electrolytes (Na+, Cl, K+, Ca2+, Mg2+, P inorganic) and heavy metals in both Faro lake water and haemolymph have been carried out. Heavy metals are elements with high density and are quite toxic in low concentrations, such as Aluminum (Al), Arsenic (As), Cobalt (Co), Chrome (Cr), Copper (Cu), Iron (Fe), Magnesium (Mg), Manganese (Mn), Lead (Pb), Tin (Sn), Zinc (Zn). Heavy metals toxicity depends, principally, on bioaccumulation processes. M. galloprovincialis is a good bio‐indicator, ideal for assess levels of environmental pollution thanks to its biological, ecological and physiological characteristics. The results of this study showed a typical fluctuation range in haemolymph and water parameters, related to the water ones; chemical‐physical parameters affected the ions (electrolytes and metals) levels in some period of the year. The study reports the interactions between biotic (Mytilus galloprovincialis) and abiotic (water parameters) components of Faro Lake, and creates reference data for further future study on the same area or on similar ones.  相似文献   
999.
Soft tissue sarcomas (STS) are a heterogeneous group of rare tumors for which identification and validation of biological markers may improve clinical management. The fraction of low‐molecular‐weight (LMW) circulating proteins and fragments of proteins is a rich source of new potential biomarkers. To identify circulating biomarkers useful for STS early diagnosis and prognosis, we analyzed 53 high‐grade STS sera using hydrogel core‐shell nanoparticles that selectively entrap LMW proteins by size exclusion and affinity chromatography, protect them from degradation and amplify their concentration for mass spectrometry detection. Twenty‐two analytes mostly involved in inflammatory and immunological response, showed a progressive increase from benign to malignant STS with a relative difference in abundance, more than 50% when compared to healthy control. 16 of these were higher in metastatic compared to non‐metastatic tumors. Cox‘s regression analysis revealed a statistical significant association between the abundance of lactotransferrin (LTF) and complement factor H‐related 5 (CFHR5) and risk of metastasis. In particular, CFHR5 was associated with the risk of metastasis. The role of circulating proteins involved in metastatic progression will be crucial for a better understanding of STS biology and patient management.  相似文献   
1000.
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