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Patients after kidney, heart and lung transplantation differ in their immunosuppressive drug regimens and in susceptibility to infectious complications with cytomegalovirus (CMV). In this study, CMV-specific T-cell responses were characterized in long-term transplant recipients and associated with the frequency of infectious complications. CMV-reactive CD4 T cells from 50 healthy controls, 68 renal, 14 heart and 24 lung transplant recipients were flow cytometrically quantified by the induction of cytokines after specific stimulation. Moreover, the immunosuppressive effect of calcineurin inhibitors on specific T-cell reactivity was quantified in vitro and compared with responses in vivo. Median CMV-specific T-cell frequencies in long-term renal (1.48%; range 0.06-17.26%) and heart transplant recipients (0.90%; 0.13-12.49%) did not differ from controls (1.82%; 0.26-21.00%). In contrast, CMV-specific T-cell levels were significantly lower in lung transplant recipients (0.50%; <0.05-4.98%) and showed a significant correlation with the frequency of infectious episodes (r =-0.57, p = 0.005). The differences within the groups were associated with increasing dosages of immunosuppressive drugs, as exemplified for calcineurin inhibitors that dose dependently reduced specific T-cell reactivity in vitro. In conclusion, monitoring CMV-specific CD4 T cells may serve as a measure for long-term disease susceptibility and may contribute to an improved management of CMV complications after lung transplantation.  相似文献   
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No more than 11 cases of carcinosarcoma of the liver have been reported in the past 40 years that fulfill the definition of hepatocellular carcinoma combined with differentiated sarcomatous elements. Most cases consist of hepatocellular carcinoma with 1 to 2 heterologous elements. We report a case of a 51-year-old woman with liver carcinosarcoma consisting of 3 carcinomatous components and 4 sarcomatous components. Hepatocellular carcinoma, fibrolamellar type, was accompanied by neuroendocrine carcinoma (neuron-specific enolase and synaptophysin positive) and adenocarcinoma (cytokeratin 7 and 20 positive). The sarcomatous elements consisted of poorly differentiated spindle cell neoplasm (vimentin positive), leiomyosarcoma (smooth muscle actin positive), rhabdomyosarcoma (desmin positive), and osteosarcoma. To our knowledge, this is the first case of liver carcinosarcoma with this many differentiated heterologous features. There are differing views on the pathogenesis of this tumor. Findings in this case support the view that metaplasia of carcinomatous cells gives rise to the sarcomatous elements.  相似文献   
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The dielectrophoretic collection spectra of antibiotic-sensitive and antibiotic-resistant strains of Staphylococcus epidermidis have been determined. These indicate that in the absence of antibiotic treatment there is a strong similarity between the dielectric properties of sensitive and resistant strains, and that there is a significant difference between the sensitive strains before and after treatment with the antibiotic streptomycin after 24 h exposure. This method offers possibilities for the assessment of bacterial resistance to antibiotics.  相似文献   
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The school environment plays an important role in children’s diets and overall health, and policies for universal free school meals have the potential to contribute to positive child health outcomes. This systematic review evaluates studies examining the association between universal free school meals and students’ school meal participation rates, diets, attendance, academic performance, and Body Mass Index (BMI), as well as school finances. The search was conducted in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA). A search for studies published in economically developed countries published through December 2020 was performed in PubMed, Education Resources Information Center (ERIC), Thomson Reuters’ Web of Science, and Academic Search Ultimate, followed by examining the references in the resultant literature. A total of 47 studies were identified and the Newcastle-Ottawa Scale (NOS) was applied to assess bias. Nearly all studies examining universal free school meals found positive associations with school meal participation. Most studies examining universal free school meals that included free lunch found positive associations with diet quality, food security, and academic performance; however, the findings of studies examining only universal free breakfast were mixed. Research findings were similarly mixed when examining attendance as an outcome. Concerns about adverse outcomes on student BMI were not supported by the literature; in fact, several studies detected a potentially protective effect of universal free school meals on BMI. Research examining the impact of universal free meals on school finances was limited, but suggest that lower-income school districts in the U.S. may have positive financial outcomes from participation in universal free school meal provisions. Additionally, providing free meals to students may be associated with improved household incomes, particularly among lower-income families with children. Further research is needed to examine the financial implications of universal free meals for both school districts and families. Overall, universal free school meals may have multiple benefits for students and countries should consider universal free school meal provisions with strong nutrition guidelines. (PROSPERO registration: CRD42020221782).  相似文献   
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We investigated the effects of oral L-glutamine (Gln) supplementation, associated or not with physical exercises, in control of glycemia, oxidative stress, and strength/power of knee muscles in elderly women. Physically active (n = 21) and sedentary (n = 23) elderly women aged 60 to 80 years were enrolled in the study. Plasma levels of D-fructosamine, insulin, reduced (GSH) and oxidized (GSSG) glutathione, iron, uric acid, and thiobarbituric acid-reactive substances (TBARs) (lipoperoxidation product), as well as knee extensor/flexor muscle torque peak and average power (isokinetic test), were assessed pre- and post-supplementation with Gln or placebo (30 days). Higher plasma D-fructosamine, insulin, and iron levels, and lower strength/power of knee muscles were found pre-supplementation in the NPE group than in the PE group. Post-supplementation, Gln subgroups showed higher levels of GSH, GSSG, and torque peak, besides lower D-fructosamine than pre-supplementation values. Higher muscle average power and plasma uric acid levels were reported in the PE + Gln group, whereas lower insulin levels were found in the NPE + Gln than pre-supplementation values. TBARs levels were diminished post-supplementation in all groups. Gln supplementation, mainly when associated with physical exercises, improves strength and power of knee muscles and glycemia control, besides boosting plasma antioxidant capacity of elderly women.  相似文献   
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The food environment in New Caledonia is undergoing a transition, with movement away from traditional diets towards processed and discretionary foods and beverages. This study aimed to develop an up-to-date food composition database that could be used to analyze food and nutritional intake data of New Caledonian children and adults. Development of this database occurred in three phases: Phase 1, updating and expanding the number of food items to represent current food supply; Phase 2, refining the database items and naming and assigning portion size images for food items; Phase 3, ensuring comprehensive nutrient values for all foods, including saturated fat and total sugar. The final New Caledonian database comprised a total of 972 food items, with 40 associated food categories and 25 nutrient values and 615 items with portion size images. To improve the searchability of the database, the names of 593 food items were shortened and synonyms or alternate spelling were included for 462 foods. Once integrated into a mobile app-based multiple-pass 24-h recall tool, named iRecall.24, this country-specific food composition database would support the assessment of food and nutritional intakes of families in New Caledonia, in a cross-sectional and longitudinal manner, and with translational opportunities for use across the wider Pacific region.  相似文献   
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Solid organ transplant recipients might be at greater risk for acquisition and mortality because of SARS-CoV-2. There are no data regarding SARS-CoV-2 seroprevalence among liver transplant (LT) recipients, and whether it is different from that of the general population or other immunosuppressed groups. We evaluated the prevalence of IgG SARS-CoV-2 antibodies among LT recipients to estimate the frequency of asymptomatic SARS-CoV-2 infection using serological assays in our outpatient clinic. We conducted a cross-sectional analysis from 10 May to 26 October 2020 of all adult (>18 years) LT recipients that underwent a routine laboratory test for the outpatient clinic follow-up at the Hospital Universitari Vall d’Hebron (Barcelona) in which we included serological testing for SARS-CoV-2. Nine out of 294 LT recipients (3.1%) tested positive for anti-SARS-CoV-2 IgG antibodies. Five of them (55.5%) had suffered clinically symptomatic SARS-CoV-2 infection confirmed by RT-PCR, four (44.4%) had presented compatible symptoms but without microbiological confirmation and only one patient (1/9, 11.1%) tested positive without any previous symptom. SARS-CoV-2 seroprevalence among LT recipients in an area highly affected by the pandemic is lower than in the general population in the same area. These results render the possibility of asymptomatic infection in LT recipients very unlikely.  相似文献   
10.
BackgroundObstructive sleep apnea–hypopnea syndrome (OSAHS) is present in 80% of patients evaluated for bariatric surgery (BS). Extensive evaluation is not widely available, but treatment is mandatory for severe cases. The Snore, Tiredness, Observed apneas and Pressure - Body mass index, Age, Neck circumference and Gender (STOP-Bang) and Epworth questionnaires and neck-to-height ratio (NHtR) are accessible clinical tools to screen for sleep and metabolic disturbances, but their utility to detect severe OSAHS in patients with severe obesity has not been determined.ObjectivesTo evaluate the cutoff point of those clinical tools that may predict severe OSAHS, confirmed by polysomnography in patients referred for BS.SettingTertiary referral center in Mexico City.MethodsWe applied the STOP-Bang and Epworth questionnaires, evaluated anthropometric characteristics, and collected samples for arterial gasometry and metabolic parameters from 68 patients with severe obesity, who were then referred for polysomnography before their evaluation for BS.ResultsOf the 68 patients participating in the study, 67.7% were female, with a median age of 43 years (35–49 years) and a body mass index (BMI) of 45.5 kg/m2 (42.4–50.9 kg/m2; 28.3% had a BMI ≥ 50 kg/m2). A STOP-Bang cutoff >5 points had a sensitivity of 60% and specificity of 90% for detecting severe OSAHS (area under the curve [AUC] = .962); meanwhile, an NHtR >.25 had a sensitivity of 90% and specificity of 52.5% (AUC = .759). The Epworth scale score >11 points had a sensitivity of 57.1% and specificity of 83.3% (AUC = .802).ConclusionClinical data may be useful to detect severe sleep apnea in high-risk populations, allowing for rapid referral and better use of resources.  相似文献   
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