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991.
ObjectiveTo further refine the Chinese Adult Strabismus-20 (CAS-20) health-related quality of life(HRQOL) questionnaire using Rasch analysis. MethodsIn this cross-sectional study, the CAS-20 questionnaire was independently completed by 246 adult strabismus patients. Based on the score for each item, Rasch analysis was performed on the original CAS-20 using the following aspects: dimensionality, response order, local dependence, infit and outfit analysis, differential item function, subject targeting and confirmatory dimensionality. ResultsThe original CAS-20 was divided into 4 subscales, which were labeled ″self-perception″, ″interaction″, ″reading function″, and ″general function″. Response ordering was appropriate for all of the 4 subscales. As a result of infit and outfit analysis, 3 items were removed, one each from ″self-perception″, ″reading function″, and ″general function″. No significant differential item function was found for sex or age. Compared with the ability of the patients and item difficulty, the 3 subscales matched well except for ″reading function″. ConclusionThe original CAS-20 was reduced to 17 items, and divided into 4 subscales, which were ″self-perception″, ″interaction″, ″reading function″, and ″general function″. Subject response choices saved 5 test options. The refined CAS-20 may prove to be more responsive to HRQOL changes in adult strabismus patients.  相似文献   
992.
Pulmonary arterial hypertension (PAH) is a severe cardiovascular disease that can lead to vascular remodelling and hypertension. Clinical diagnosis of PAH is very difficult. Uric acid (UA) can act as a biological marker for screening of PAH in patients. Multiple studies have indicated that reactive oxygen species (ROS) play an important role in the development of PAH. Thus, it is important to study the relationship between UA and ROS based on the pathogenesis of PAH. For monitoring PAH, a high performance liquid chromatography-electrospray ionization-tandem mass spectrometry (HPLC-ESI-MS/MS) method was developed to measure the concentration of UA from rat models and pulmonary arterial endothelial cells (PAECs) models, which were induced by monocrotaline (MCT) and hypoxia, respectively. In addition, the treatment groups were treated by N-acetyl-l-cysteine (NAC), a ROS scavenger. With the confirmation from hematoxylin-eosin (H&E) staining, the HPLC-ESI-MS/MS method was adopted to successfully analyze the concentration of UA. In this study, for the first time, thymine was used as an internal standard (I.S.) of uric acid. The results showed that the UA concentration in the PAH groups was higher than that in the normal groups, while the UA concentration in the treatment groups decreased compared to that in the PAH group (p < 0.05). It was experimentally proven that the HPLC-ESI-MS/MS method is a rapid, efficient and reliable quantitative method to detect PAH. Furthermore, our results indicated that UA and ROS have a double-regulator role.

Thymine firstly was used as an internal standard for uric acid.  相似文献   
993.
A cyclodextrin aldehyde based molecularly imprinted polymer with thermally responsive Diels–Alder (DA) linkages of grafted furan-type dienes was polymerized. The synthesized DA-MIP has dienophile characteristics and the specific absorption of ethyl carbamate (EC) can be switched on or off simply by thermal adjustment to 130 °C and 60 °C, respectively. The imprinting factors (α) of the MIP and rDA-MIP to EC were 6.2 and 5.0, and the selection factors (β) were 5.2 and 4.0, respectively. The restoration of the molecular target ratio was 88%, as determined by absorption and desorption experiments. The thermal restoration ratio, determined by thermal cycling experiments, was 78%. A new electrochemical sensor was prepared using the DA-MIP and its responsiveness for detecting trace amounts of EC was investigated. The results indicate that the electrode response has good affinity and excellent specific recognition performance for template molecular chemicals.

A cyclodextrin aldehyde based molecularly imprinted polymer with thermally responsive Diels–Alder (DA) linkages of grafted furan-type dienes was polymerized. The synthesized DA-MIP has dienophile characteristics and the specific adsorption of ethyl carbamate (EC) can be switched on or off simply by thermal adjustment.   相似文献   
994.
Calcium phosphate (CaP) has similar chemical properties to those of the inorganic component of human bone tissue, for potential application in drug delivery for the chemotherapy of osteosarcoma. In this work, CaP with a porous microsphere structure has been synthesized using fructose-1,6-bisphosphate (FBP) as the phosphorus source by a simple wet-chemical strategy at room temperature. The CaP porous microspheres, as an organic–inorganic hybrid nano-platform, exhibit good doxorubicin (Dox) loading capacity, and Dox-loading CaP, enhancing the in vitro chemotherapy of osteosarcoma cells. The CaP porous microspheres show high biocompatibility, and induce the osteogenic differentiation of MC3T3-E1. These results indicate that the CaP porous microspheres reported in this study are promising for application as an anti-osteosarcoma drug carrier and osteoinductive material for bone regeneration in the treatment of osteosarcoma.

Porous calcium phosphate microspheres were prepared at room temperature, and displayed potential for application in the chemotherapy of osteosarcoma and osteogenic differentiation.  相似文献   
995.

Background and Purpose

Recent reports have suggested that salidroside could protect cardiomyocytes from oxidative injury and stimulate glucose uptake in skeletal muscle cells by activating AMP-activated protein kinase (AMPK). The aim of this study was to evaluate the therapeutic effects of salidroside on diabetic mice and to explore the underlying mechanisms.

Experimental Approach

The therapeutic effects of salidroside on type 2 diabetes were investigated. Increasing doses of salidroside (25, 50 and 100 mg·kg−1·day−1) were administered p.o. to db/db mice for 8 weeks. Biochemical analysis and histopathological examinations were conducted to evaluate the therapeutic effects of salidroside. Primary cultured mouse hepatocytes were used to further explore the underlying mechanisms in vitro.

Key Results

Salidroside dramatically reduced blood glucose and serum insulin levels and alleviated insulin resistance. Hypolipidaemic effects and amelioration of liver steatosis were observed after salidroside administration. In vitro, salidroside dose-dependently induced an increase in the phosphorylations of AMPK and PI3K/Akt, as well as glycogen synthase kinase 3β (GSK3β) in hepatocytes. Furthermore, salidroside-stimulated AMPK activation was found to suppress the expression of PEPCK and glucose-6-phosphatase. Salidroside-induced AMPK activation also resulted in phosphorylation of acetyl CoA carboxylase, which can reduce lipid accumulation in peripheral tissues. In isolated mitochondria, salidroside inhibited respiratory chain complex I and disturbed oxidation/phosphorylation coupling and moderately depolarized the mitochondrial membrane potential, resulting in a transient increase in the AMP/ATP ratio.

Conclusions and Implications

Salidroside exerts an antidiabetic effect by improving the cellular metabolic flux through the activation of a mitochondria-related AMPK/PI3K/Akt/GSK3β pathway  相似文献   
996.
Penicillium cyclopium lipase I (PCL) is a thermolabile triacylglycerol lipase with very low activity against monoacylglycerols, and there have been no reports on the transesterification of oil to produce biodiesel. A mutant PCLG47I with an improved thermostability was previously obtained through replacing Gly47 with Ile in PCL. In this study, a novel Pichia pastoris whole-cell biocatalyst (WCB) with overexpression of PCLG47I was constructed and characterized for biodiesel production from soybean oil. The optimum conditions for biodiesel preparation were 1 g soybean oil, 1 : 2 initial oil/methanol molar ratio with 3 times methanol addition of 1 : 0.75 oil/methanol molar ratio at 4 h intervals, 7% water content, 400 U lipase, temperature of 25 °C, and reaction time of 20 h. Under the optimum conditions, the FAME yield reached 60.7% and remained 47.3% after 4 batch cycles, and no glycerol was generated as a byproduct. These findings indicated that this WCB is a promising biocatalyst for biodiesel production in a relatively cost-effective manner. Additionally, the resulting enzymatic process may provide a potential method for biodiesel production at an industrial scale.

Biodiesel is efficiently produced by a lipase whole-cell biocatalyst with high activity and thermostability at low temperature.  相似文献   
997.
In this study, a convenient and sensitive method for the detection of resveratrol was established based on phosphorescence quenching of resveratrol for MPA-capped Mn:ZnS QDs. The quenching intensity was in proportion to the concentration of resveratrol within a certain range. Under optimal conditions, the present assay was valid for detecting resveratrol in the range from 0.03 μM to 14 μM with a detection limit of 0.01 μM. The mechanism of action was also explored, and its application in actual samples was also demonstrated with satisfactory results. This study aims to provide a convenient method for the detection of resveratrol.

In this study, a convenient and sensitive method for the detection of resveratrol was established based on phosphorescence quenching of resveratrol for MPA-capped Mn:ZnS QDs.  相似文献   
998.
Titanium dioxide nanoparticles (TiO2 NPs) are widely found in food‐related consumer products. Understanding the effect of TiO2 NPs on the intestinal barrier and absorption is essential and vital for the safety assessment of orally administrated TiO2 NPs. In this study, the cytotoxicity and translocation of two native TiO2 NPs, and these two TiO2 NPs pretreated with the digestion simulation fluid or bovine serum albumin were investigated in undifferentiated Caco‐2 cells, differentiated Caco‐2 cells and Caco‐2 monolayer. TiO2 NPs with a concentration less than 200 µg ml–1 did not induce any toxicity in differentiated cells and Caco‐2 monolayer after 24 h exposure. However, TiO2 NPs pretreated with digestion simulation fluids at 200 µg ml–1 inhibited the growth of undifferentiated Caco‐2 cells. Undifferentiated Caco‐2 cells swallowed native TiO2 NPs easily, but not pretreated NPs, implying the protein coating on NPs impeded the cellular uptake. Compared with undifferentiated cells, differentiated ones possessed much lower uptake ability of these TiO2 NPs. Similarly, the traverse of TiO2 NPs through the Caco‐2 monolayer was also negligible. Therefore, we infer the possibility of TiO2 NPs traversing through the intestine of animal or human after oral intake is quite low. This study provides valuable information for the risk assessment of TiO2 NPs in food. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
999.
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