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991.
The purpose of this study was to investigate the role of infliximab on acute lung injury induced by intestinal ischemia/reperfusion (I/R). A total of 30 male Wistar albino rats were divided into three groups: sham, I/R and I/R+ infliximab; each group contain 10 animals. Sham group animals underwent laparotomy without I/R injury. After I/R groups animals underwent laparotomy, 1 h of superior mesenteric artery ligation were followed by 1 h of reperfusion. In the infliximab group, 3 days before I/R, infliximab (3 mg/kg) was administered by intravenously. All animals were sacrificed at the end of reperfusion and lung tissues samples were obtained for biochemical and histopathological investigation in all groups. To date, no more biochemical and histopathological changes on intestinal I/R injury in rats by infliximab treatment have been reported. Infliximab treatment significantly decreased the elevated tissue malondialdehyde levels and increased of reduced superoxide dismutase, and glutathione peroxidase enzyme activities in lung tissues samples. Intestinal I/R caused severe histopathological injury including edema, hemorrhage, increased thickness of the alveolar wall and a great number of inflammatory cells that infiltrated the interstitium and alveoli. Infliximab treatment significantly attenuated the severity of intestinal I/R injury. Furthermore, there is a significant reduction in the activity of inducible nitric oxide synthase and arise in the expression of surfactant protein D in lung tissue of acute lung injury induced by intestinal I/R with infliximab therapy. It was concluded that infliximab treatment might be beneficial in acute lung injury, therefore, shows potential for clinical use. Because of its anti-inflammatory and antioxidant effects, infliximab pretreatment may have protective effects in acute lung injury induced by intestinal I/R.  相似文献   
992.
The aim of this study was to evaluate the therapeutic efficacy of caffeic acid phenethyl ester (CAPE) with an experimental traumatic brain injury (TBI) model in rats. Twenty-four adult male Sprague–Dawley rats were randomly divided into three groups of 8 rats each: control, TBI, and TBI + CAPE treatment. In TBI and TBI + CAPE treatment groups, a cranial impact was delivered to the skull from a height of 7 cm at a point just in front of the coronal suture and over the right hemisphere. Rats were sacrificed at 4 h after the onset of injury. Brain tissues were removed for biochemical and histopathological investigation. To date, no biochemical and histopathological changes of neurodegeneration in the frontal cortex after TBI in rats by CAPE treatment have been reported. The TBI significantly increased tissue malondialdehyde (MDA) levels, and significantly decreased tissue superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities, but not tissue catalase (CAT) activity, when compared with controls. The administration of a single dose of CAPE (10 μmol/kg) 15 min after the trauma has shown protective effect via decreasing significantly the elevated MDA levels and also significantly increasing the reduced antioxidant enzyme (SOD and GPx) activities, except CAT activity. In the TBI group, severe degenerative changes, shrunken cytoplasma and extensively dark picnotic nuclei in neurons, as well as vacuolization indicating tissue edema formation. The morphology of neurons in the CAPE treatment group was well protected. The number of neurons in the trauma alone group was significantly less than that of both the control and TBI +CAPE treatment groups. The caspase 3 immunopositivity was increased in degenerating neurons of the traumatic brain tissue. Treatment of CAPE markedly reduced the immunoreactivity of degenerating neurons. TBI caused severe degenerative changes, shrunken cytoplasma, severely dilated cisternae of endoplasmic reticulum, markedly swollen mitochondria with degenerated cristae and nuclear membrane breakdown with chromatin disorganization in neurons of the frontal cortex. In conclusion, the CAPE treatment might be beneficial in preventing trauma-induced oxidative brain tissue damage, thus showing potential for clinical implications. We believe that further preclinical research into the utility of CAPE may indicate its usefulness as a potential treatment on neurodegeneration after TBI in rats.  相似文献   
993.
994.
A new series of N,N'-diarylureas (1-9) was synthesized. These compounds were investigated as inhibitors of polyphenol oxidase (PPO) which had been purified from banana by an affinity gel comprised of Sepharose 4B-l-tyrosine-p-amino benzoic acid. K(i) values for (1), (2), (3), (5), (6), (7) and (8) were determined as 0.285, 17.97, 0.187, 0.108, 0.063, 0.044 and 0.047?mM, respectively. Thus (2) was by far the most effective inhibitor. Interestingly, (4) and (9) behaved as an activator of PPO in this study.  相似文献   
995.

Introduction

Rheumatoid arthritis (RA) is a multifactorial autoimmune disease in which genetic and environmental factors interact in the etiology. In this study, we investigated whether smoking and HLA-DRB1 shared-epitope (SE) alleles interact differently in the development of the two major subgroups of rheumatoid arthritis (RA), anti-citrullinated proteins antibody (ACPA)-positive and ACPA-negative disease, in a multiethnic population of Asian descent.

Methods

A case-control study comprising early diagnosed RA cases was carried out in Malaysia between 2005 and 2009. In total, 1,076 cases and 1,612 matched controls participated in the study. High-resolution HLA-DRB1 genotyping was performed for shared-epitope (SE) alleles. All participants answered a questionnaire on a broad range of issues, including smoking habits. The odds ratio (OR) of developing ACPA-positive and ACPA-negative disease was calculated for smoking and the presence of any SE alleles separately. Potential interaction between smoking history (defined as "ever" and "never" smoking) and HLA-DRB1 SE alleles also was calculated.

Results

In our multiethnic study, both the SE alleles and smoking were associated with an increased risk of developing ACPA-positive RA (OR SE alleles, 4.7; 95% confidence interval (CI), 3.6 to 6.2; OR smoking, 4.1; 95% CI, 1.9 to 9.2). SE-positive smokers had an odds ratio of ACPA-positive RA of 25.6 (95% CI, 10.4 to 63.4), compared with SE-negative never-smokers. The interaction between smoking and SE alleles was significant (attributable proportion due to interaction (AP) was 0.7 (95% CI, 0.5 to 1.0)). The HLA-DRB1*04:05 SE allele, which is common in Asian populations, but not among Caucasians, was associated with an increased risk of ACPA-positive RA, and this allele also showed signs of interaction with smoking (AP, 0.4; 95% CI, -0.1 to 0.9). Neither smoking nor SE alleles nor their combination was associated with an increased risk of ACPA-negative RA.

Conclusions

The risk of developing ACPA-positive RA is associated with a strong gene-environment interaction between smoking and HLA-DRB1 SE alleles in a Malaysian multiethnic population of Asian descent. This interaction seems to apply also between smoking and the specific HLA-DRB1*04:05 SE allele, which is common in Asian populations but not in Caucasians.  相似文献   
996.
The frog Xenopus has been vital for biomedical science for over 80 years, contributing to diverse fields from cell signaling, cell and developmental biology, to ion channel physiology and toxicology. Its experimentally manipulable oocytes and embryos provide abundant material for molecular and biochemical approaches for a wide range of gene discovery and protein function studies. In recent years, the Xenopus community has invested in key resources for functional genomics, including genome-wide full-length cDNA collections and genome assemblies as well as genetic tools. These assets combine with Xenopus' extensive range of functional assays to create exciting new research avenues with medical as well as basic applications. This review describes how these resources were developed and what new tools are on the horizon.  相似文献   
997.
Hepatic glucose production (HGP) is crucial for glucose homeostasis, but the underlying mechanisms have not been fully elucidated. Here, we show that a calcium-sensing enzyme, CaMKII, is activated in a calcium- and IP3R-dependent manner by cAMP and glucagon in primary hepatocytes and by glucagon and fasting in vivo. Genetic deficiency or inhibition of CaMKII blocks nuclear translocation of FoxO1 by affecting its phosphorylation, impairs fasting- and glucagon/cAMP-induced glycogenolysis and gluconeogenesis, and lowers blood glucose levels, while constitutively active CaMKII has the opposite effects. Importantly, the suppressive effect of CaMKII deficiency on glucose metabolism is abrogated by transduction with constitutively nuclear FoxO1, indicating that the effect of CaMKII deficiency requires nuclear exclusion of FoxO1. This same pathway is also involved in excessive HGP in the setting of obesity. These results reveal a calcium-mediated signaling pathway involved in FoxO1 nuclear localization and hepatic glucose homeostasis.  相似文献   
998.
Honey mesquite (Prosopis glandulosa Torr.), a multistemmed tree that grows on grasslands and rangelands in the South Central USA (Texas, Oklahoma, and New Mexico), may have potential as a bioenergy feedstock due to a large amount of existing standing biomass and significant regrowth potential following initial harvest. The objective of this research was to determine the cost to harvest, store, and deliver mesquite biomass feedstock to a bioelectricity plant under the assumption that the rights to harvest mesquite could be acquired in long-term leases. The advantage of mesquite and similar rangeland shrubs as bioenergy feedstocks is that they do not grow on land better suited for growing food or fiber and thus will not impact agricultural food markets as corn grain ethanol has done. In addition, there are no cultivation costs. Results indicated that mesquite biomass density (Mg?ha?1) and harvesting costs are major factors affecting cost of delivered biomass. Annual biomass consumption by the bioelectricity plant and percent of the total system area that contains biomass density that is suitable for harvest significantly affected land- related factors including total system area needed per bioelectricity plant and transport costs. Simulation results based on actual biomass density in Texas showed that higher and more spatially consistent biomass density would be an important factor in selecting a potential location for the bioelectricity plant. Harvesting mesquite has the potential for bioenergy feedstock given certain densities and total land areas since higher harvest and transport costs are offset by essentially no production costs.  相似文献   
999.
Tomographic imaging has been a widely used tool in medicine as it can provide three-dimensional (3D) structural information regarding objects of different size scales. In micrometer and millimeter scales, optical microscopy modalities find increasing use owing to the non-ionizing nature of visible light, and the availability of a rich set of illumination sources (such as lasers and light-emitting-diodes) and detection elements (such as large format CCD and CMOS detector-arrays). Among the recently developed optical tomographic microscopy modalities, one can include optical coherence tomography, optical diffraction tomography, optical projection tomography and light-sheet microscopy. 1-6 These platforms provide sectional imaging of cells, microorganisms and model animals such as C. elegans, zebrafish and mouse embryos.Existing 3D optical imagers generally have relatively bulky and complex architectures, limiting the availability of these equipments to advanced laboratories, and impeding their integration with lab-on-a-chip platforms and microfluidic chips. To provide an alternative tomographic microscope, we recently developed lensfree optical tomography (LOT) as a high-throughput, compact and cost-effective optical tomography modality. 7 LOT discards the use of lenses and bulky optical components, and instead relies on multi-angle illumination and digital computation to achieve depth-resolved imaging of micro-objects over a large imaging volume. LOT can image biological specimen at a spatial resolution of <1 μm x <1 μm x <3 μm in the x, y and z dimensions, respectively, over a large imaging volume of 15-100 mm3, and can be particularly useful for lab-on-a-chip platforms.  相似文献   
1000.
Acne vulgaris is the one of the most common skin diseases. Although isotretinoin (13-cis-retinoic acid) is an effective and well-tolerated medication, it has a wide range of side effects. Because the effects of isotretinoin on oxidant and antioxidant systems have not yet been clarified, we investigated plasma and erythrocyte antioxidant vitamins, lipid peroxidation (LP), reduced glutathione (GSH) and glutathione peroxidase (GSH-Px) values in patients with acne vulgaris before and after isotretinoin treatment. The study was performed on the blood plasma and erythrocytes of 31 acne vulgaris patients. Blood samples were taken from the patients before treatment and after isotretinoin (oral and 0·5-0·7?mg·kg(-1) ) treatment for 2?months. Plasma amtioxidant vitamins, erythrocyte malondialdehyde, GSH and GSH-Px levels were measured. Plasma vitamin E (p?相似文献   
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