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51.
The preoperative radiographs of 1015 patients undergoing 1163 total hip replacements for osteoarthritis were evaluated to determine if a relationship exists between the extent of osteoarthritis and the clinical results of a total hip replacement. Preoperative radiographs were graded with respect to the degree of cartilage space loss, direction of cartilage space loss (femoral head migration), and severity of osteophyte formation. Followup averaged 32.1 months (range, 6-93 months). Greater degrees of cartilage space loss correlated with lower hip scores preoperatively but were unrelated to preoperative pain. These patients had statistically less pain at 6 months and 1 year. Patients with superior cartilage space loss before surgery also had statistically less pain at 6 months. However, at 3 years and beyond, pain was independent of degree of preoperative cartilage space loss, osteophyte formation, or femoral head migration. In addition, hip scores at any followup were independent of the degree of osteoarthritis observed on the preoperative radiograph. These findings provide statistical support to the concept that greater degrees of joint space loss correlate with better relief of pain and less severe joint space loss correlates with less relief of pain within the first year after total hip replacement. At 3 years and beyond, hip and pain scores were independent of the degree of preoperative osteoarthritis.  相似文献   
52.
Background:Virtual reality (VR) is an advanced technique used in physical rehabilitation of neurological disorders, however the effects of VR on balance, gait, and motor function in people with Parkinson’s (PD) are still debated. Therefore, the systematic review aimed to determine the role of VR on motor function, balance and gait in PD patients.Methods:A comprehensive search to identify similar randomised controlled trials was conducted targeting 5 databases including Web of Science, PubMed, CINHAL, Cochrane Library, and Physiotherapy Evidence Database. A total of 25 studies were found eligible for this systematic review, and the methodological assessment of the quality rating of the studies was accomplished using the physiotherapy evidence database scale by 2 authors.Results:Out of the 25 included studies, 14 studies reported on balance as the primary outcome, 9 studies were conducted to assess motor function, and 12 assessed gait as the primary outcome. Most studies used the Unified Parkinson disease rating scale UPDRS (part-III) for evaluating motor function and the Berg Balance Scale as primary outcome measure for assessing balance. A total of 24 trials were conducted in clinical settings, and only 1 study was home-based VR trainings. Out of 9 studies on motor function, 6 reported equal improvement of motor function as compared to other groups. In addition, VR groups also revealed superior results in improving static balance among patient with PD.Conclusion:This systemic review found that the use of VR resulted in substantial improvements in balance, gait, and motor skills in patients with PD when compared to traditional physical therapy exercises or in combination with treatments other than physical therapy. Moreover, VR can be used as a supportive method for physical rehabilitation in patients of PD. However, the majority of published studies were of fair and good quality, suggesting a demand for high quality research in this area.  相似文献   
53.
Axitinib is a potent vascular endothelial growth factor receptor (VEGFR) inhibitor, which has a strong inhibitory effect on the three isoforms of VEGFR 1–3. Having strong therapeutic efficacy, its broad use is limited by its side effects such as hypertension, proteinuria, cardiovascular damage, and liver and kidney dysfunction. Selenium compounds are broadly reported to have a good protective effect on cardiovascular disease, inflammation, infection, and immune function. In this study, a selenium substitute of axitinib was synthesized, and its anti-renal cell carcinoma activity and side effects were investigated. The results of the study indicated that Se-axitinib had potent antitumor activity on renal cell carcinoma (RCC), alleviated vascular hyperpermeability, and also alleviated axitinib-related side effects including hypertension, liver dysfunction and kidney dysfunction significantly. Therefore, we suggest that Se-axitinib could be a solution to the severe side effects of VEGFR inhibitors and provide evidence to improve the outcome of RCC treatment.

Se-axitinib is a selenium substitution of sulfur in axitinib, which reduced the side effect of VEGFR inhibitors and maintained the potent anticancer activity of the original drug.  相似文献   
54.
A recently independent state, Timor-Leste, is progressing towards socioeconomic development, prioritizing women empowerment while its increased fertility rate (4.1) could hinder the growth due to an uncontrolled population. Currently, limited evidence shows that indicators of women''s empowerment are associated with fertility preferences and rates. The objective of this study was to assess the association between women empowerment and fertility preferences of married women aged 15 to 49 years in Timor-Leste using nationally representative survey data. The study was conducted using the data of the latest Timor-Leste Demographic and Health Survey 2016. The study included 4040 rural residents and 1810 urban residents of Timor-Leste. Multinomial logistic regression has been performed to assess the strength of association between the exposures indicating women''s empowerment and outcome (fertility preference). After adjusting the selected covariates, the findings showed that exposures that indicate women empowerment in DHS, namely, the employment status of women, house and land ownership, ownership of the mobile phone, and independent bank account status, contraceptive use, and the attitude of women towards negotiating sexual relations are significantly associated with fertility preferences. The study shows higher the level of education, the less likely were the women to want more children, and unemployed women were with a higher number of children. Our study also found that the attitude of violence of spouses significantly influenced women''s reproductive choice. However, employment had no significant correlation with decision-making opportunities and contraceptive selection due to a lack of substantial data. Also, no meaningful data was available regarding decision-making and fertility preferences. Our findings suggest that women''s empowerment governs decision-making in fertility preferences, causing a decline in the fertility rate.  相似文献   
55.
56.
Steel plates with openings are among the important ship structural components used in the ship’s hull to withstand the hydrostatic forces of the ocean, which cause sagging and hogging moments at the ship’s bottom. The existence of openings on plates can cause structural rupture, stress concentration and a decrease in ultimate strength. This research is aimed at investigating the influence of selected parameters on the ultimate capacity of steel plates with rectangular holes subjected to axial stress, using ANSYS finite element analysis (FEA) under its non-linear static structural programme. The main parameters investigated in this paper are the plate thickness, opening aspect ratio, number of openings, position of openings, and the boundary condition of the plate. The influence of these parameters on the stress of plates and their deformation was evaluated. The comparison of the numerical simulation with the well-established analytical method using the Navier solution and Roark’s Formulas showed a good agreement.  相似文献   
57.
The development of cost-effective co-catalysts of high photocatalytic activity and recyclability is still a challenge in the energy transformation domain. In this study, 0D/2D Schottky heterojunctions, consisting of 0D ZnO and 2D Ti3C2, were successfully synthesized by the electrostatic self-assembling of ZnO nanoparticles on Ti3C2 nanosheets. In constructing these heterojunctions, Ti3C2 nanosheets acted as a co-catalyst for enhancing the transfer of excitons and their separation to support the photocatalytic response of ZnO. The as-prepared ZnO/Ti3C2 composites demonstrate an abbreviated charge transit channel, a huge interfacial contact area and the interfacial electrons’ transport potential. The extended optical response and large reactive area of the ZnO/Ti3C2 composite promoted the formation of excitons and reactive sites on the photocatalyst’s surface. The ZnO/Ti3C2 Schottky heterojunction showed significantly high photocatalytic activity for hydrogen production from a water–ethanol solution under the light illumination in the visible region. The hydrogen evolution overoptimized the ZnO/Ti3C2 composition with 30 wt.% of Ti3C2, which was eight times higher than the pristine ZnO. These findings can be helpful in developing 0D/2D heterojunction systems for photocatalytic applications by utilizing Ti3C2 as a low-cost co-catalyst.  相似文献   
58.
Photocatalytic materials attract immense scientific interest due to their possible applications in energy harvesting. These applications are strongly dependent on the material''s band gap and efficient visible light absorption, which ultimately relies on the underlying electronic structure of the material. In this work, we have theoretically studied the electronic and optical response of a Cu3P semiconductor. We have used Density Functional Theory (DFT), and the Many-Body Perturbation Theory (MBPT) based Bethe–Salpeter Equation (BSE). Cu3P has intriguing band gap nature, as DFT predicts a semi-metallic state which was corrected by employing the Hubbard potentials. Only astronomically large values of Hubbard potentials reproduced the semiconducting state of Cu3P. The optical response of the material is computed within a Random Phase Approximation (RPA) and using the BSE on top of DFT+U wavefunctions and on the ground state computed with the PBE0 functional. The BSE captures the excitonic physics, and the optical absorption obtained from it was red-shifted compared to the RPA, which shows the significance of electron–hole interactions in Cu3P. The comparison of the BSE with experiments suggests that BSE@PBE0 reproduces the optical absorption much more closely to the experimental data.

The optical absorption from BSE@PBE0 is in better agreement with the experiment than BSE@DFT+U. The electron–hole interaction and strong correlation between electrons play a vital role in the optoelectronic response of Cu3P.  相似文献   
59.
The use of medical devices for therapeutic and diagnostic purpose is globally increasing; however, bacterial colonization on therapeutic devices can occur, causing severe infections in the human body. It has become an issue for public health. It is necessary to develop a nanomaterial based on photothermal treatment to kill toxic bacterial strains. Appropriately, high photothermal conversion and low-cost powerful photothermal agents have been investigated. Recently, gold nanocomposites have attracted great interest in biological applications. Here, we prepared rod-shaped Se-Te@Au nanocomposites of about 200 nm with uniform shape and surface-coated with gold nanoparticles for the first time showing high anti-bacterial and anti-cancer activities. Se-Te@Au showed proper structural consistency and natural resistance to bacterial and cancer cells. The strong absorption and high photothermal conversion efficacy made it a good photothermal agent material for the photothermal treatment of bacterial and cancer cells. The Se-Te@Au rod showed excellent anti-bacterial efficacy against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus, with highest recorded inhibition zones of 25 ± 2 mm and 22 ± 2 mm, respectively. More than 99% of both types of strains were killed after 5 min with a near-infrared (NIR) laser at the very low concentration of 48 µg/mL. The Se-Te@Au rod’s explosion in HeLa cells was extensively repressed and demonstrated high toxicity at 100 µg/mL for 5 min when subjected to an NIR laser. As a result of its high photothermal characteristics, the exceptional anti-bacterial and anti-cancer effects of the Se-Te@Au rod are considerably better than those of other methods previously published in articles. This study could open a new framework for sterilization applications on the industrial level.  相似文献   
60.
Metal foams possess remarkable properties, such as lightweight, high compressive strength, lower specific weight, high stiffness, and high energy absorption. These properties make them highly desirable for many engineering applications, including lightweight materials, energy-absorption devices for aerospace and automotive industries, etc. For such potential applications, it is essential to understand the mechanical behaviour of these foams. Producing metal foams is a highly challenging task due to the coexistence of solid, liquid, and gaseous phases at different temperatures. Although numerous techniques are available for producing metal foams, fabricating foamed metal still suffers from imperfections and inconsistencies. Thus, a good understanding of various processing techniques and properties of the resulting foams is essential to improve the foam quality. This review discussed the types of metal foams available in the market and their properties, providing an overview of the production techniques involved and the contribution of metal foams to various applications. This review also discussed the challenges in foam fabrications and proposed several solutions to address these problems.  相似文献   
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