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The International Journal of Cardiovascular Imaging - To examine the feasibility of the quantification of abdominal periaortic fat tissue (PaFT) (tissue within − 45 to...  相似文献   
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The purpose of this study is to describe the MR imaging features of bone marrow in beta-thalassemia major and investigate their relation to ferritin, liver and spleen siderosis. Spinal bone marrow was prospectively assessed on abdominal MR studies of 40 transfused beta-thalassemic patients and 15 controls using T1-w, Pd, T2*-w Gradient Echo (GRE) and T1-w turbo Spin Echo (TSE) sequences. Signal intensity (SI) ratios of liver, spleen and bone marrow to paraspinous muscles (L/M, S/M, B/M respectively) and the respective T2 relaxation rates (1/T2) were calculated. Serum ferritin levels were recorded. Bone marrow hypointensity in at least T2*-w GRE sequence was noted in 29/40 (72.5%) patients. Eleven/40 patients exhibited normal B/M on all MR sequences. Five/40 patients had normal B/M and low L/M. B/M correlated with L/M in T1-w TSE sequence only (r = 0.471, p = 0.05). B/M correlated with S/M and mean ferritin values in all sequences (r > 0.489, p < 0.01 and r  >  − 0.496, p < 0.03 respectively). Marrow 1/T2 did not correlate with ferritin values or liver and spleen 1/T2. B/M in transfused beta-thalassemic patients is related to splenic siderosis and ferritin levels. Although marrow is usually hypointense, it may occasionally display normal SI coexisting with liver hypointensity, a pattern typical of primary hemochromatosis.  相似文献   
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BACKGROUND: Clinical tests used for the detection of meniscal tears in the knee do not present acceptable diagnostic sensitivity and specificity values. Diagnostic accuracy is improved by arthroscopic evaluation or magnetic resonance imaging studies. The objective of this study was to evaluate the diagnostic accuracy of a new dynamic clinical examination test for the detection of meniscal tears. METHODS: Two hundred and thirteen symptomatic patients with knee injuries who were examined clinically, had magnetic resonance imaging studies performed, and underwent arthroscopic surgery and 197 asymptomatic volunteers who were examined clinically and had magnetic resonance imaging studies done of their normal knees were included in this study. For clinical examination, the medial and lateral joint-line tenderness test, the McMurray test, the Apley compression and distraction test, the Thessaly test at 5 degrees of knee flexion, and the Thessaly test at 20 degrees of knee flexion were used. For all clinical tests, the sensitivity, specificity, false-positive, false-negative, and diagnostic accuracy rates were calculated and compared with the arthroscopic and magnetic resonance imaging data for the test subjects and the magnetic resonance imaging data for the control population. RESULTS: The Thessaly test at 20 degrees of knee flexion had a high diagnostic accuracy rate of 94% in the detection of tears of the medial meniscus and 96% in the detection of tears of the lateral meniscus, and it had a low rate of false-positive and false-negative recordings. Other traditional clinical examination tests, with the exception of joint-line tenderness, which presented a diagnostic accuracy rate of 89% in the detection of lateral meniscal tears, showed inferior rates. CONCLUSIONS: The Thessaly test at 20 degrees of knee flexion can be used effectively as a first-line clinical screening test for meniscal tears, reducing the need for and the cost of modern magnetic resonance imaging methods.  相似文献   
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Beyond lowering lipid levels, 3-hydroxy-3-methyl glutaryl coenzyme A reductase inhibitors (statins) have been shown to possess antioxidant properties, which may explain some of their beneficial effects in reducing atherosclerosis. We sought to determine whether circulating oxidized low-density lipoprotein (ox-LDL) levels differ between subjects with isolated hypercholesterolemia and combined hyperlipidemia, as well as the effect of simvastatin on circulating ox-LDL according to the type of dyslipidemia. Twenty-five subjects with total cholesterol >200 mg/dl and triglycerides <150 mg/dl, and 22 subjects with total cholesterol >200 mg/dl and triglycerides >150 mg/dl were treated with 40 mg simvastatin daily for 3 months. Serum lipids, C-reactive protein, fibrinogen, ox-LDL, and free radicals were measured at baseline and after 3 months of treatment. In both groups studied, simvastatin significantly improved lipids, and reduced C-reactive protein and fibrinogen levels. Free radicals were significantly reduced only in subjects with hypercholesterolemia. Subjects with combined hyperlipidemia had significantly higher baseline levels of ox-LDL compared to those with hypercholesterolemia (64.6 U/l vs 53.5 U/l, P = 0.03). Ox-LDL levels were reduced by 12% in subjects with hypercholesterolemia (P = 0.03) and by 26% in subjects with combined hyperlipidemia (P = 0.001) after simvastatin treatment. In conclusion, subjects with combined hyperlipidemia have increased levels of circulating ox-LDL compared to subjects with isolated hypercholesterolemia. Simvastatin significantly reduced circulating ox-LDL in both groups, but whether this reduction is related to clinical outcomes remains to be shown.  相似文献   
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ObjectiveThe present study aimed to develop and evaluate a simple diagnostic model that could aid physicians to discriminate between infectious and non-infectious causes of fever of unknown origin (FUO).Design/Setting/SubjectsPatients with classical FUO were studied in two distinct, prospective, observational phases. In the derivation phase that lasted from 1992 to 2000, 33 variables regarding demographic characteristics, history, symptoms, signs, and laboratory profile were recorded and considered in a logistic regression analysis using the diagnosis of infection as a dependent variable. In the validation phase, the discriminatory capacity of a score based on the derived predictors of infection was calculated for FUO patients assessed from 2001 to 2007.ResultsData from 112 individuals (mean age 56.5 ± 11.2 years) were analyzed in the derivation cohort. The final diagnoses included infections, malignancies, non-infectious inflammatory diseases, and miscellaneous conditions in 30.4%, 10.7%, 33% and 5.4% of subjects, whereas 20.5% of cases remained undiagnosed. C-reactive protein > 60 mg/L (odds ratio 6.0 [95% confidence intervals 2.5, 9.8]), eosinophils < 40/mm3 (4.1 [2.0, 7.3]) and ferritin < 500 μg/L (2.5 [1.3, 5.2]) were independently associated with diagnosis of infection. Among the 100 patients of the validation cohort, the presence of ≥ 2 of the above factors predicted infection with sensitivity, specificity, and positive and negative predictive values of 91.4%, 92.3%, 86.5%, and 95.2%, respectively.ConclusionsThe combination of C-reactive protein, ferritin and eosinophil count may be useful in discriminating infectious from non-infectious causes in patients hospitalised for classical FUO.  相似文献   
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Numerous studies have shown the presence of high levels of growth factors during the process of healing. Growth factors act by binding to the cell surface receptors and contribute to the subsequent activation of signal transduction mechanisms. Wound healing requires a complex of biological and molecular events that includes attraction and proliferation of different type of cells to the wound site, differentiation and angiogenesis. More specifically, migration of various cell types, such as endothelial cells and their precursors, mesenchymal stem/stromal cells (MSCs) or skin fibroblasts (DFs) plays an important role in the healing process. In recent years, the application of platelet rich plasma (PRP) to surgical wounds and skin ulcerations is becoming more frequent, as it is believed to accelerate the healing process. The local enrichment of growth factors at the wound after PRP application causes a stimulation of tissue regeneration. Herein, we studied: (i) the effect of autologous PRP in skin ulcers of patients of different aetiology, (ii) the proteomic profile of PRP, (iii) the migration potential of amniotic fluid MSCs and DFs in the presence of PRP extract in vitro, (iv) the use of the PRP extract as a substitute for serum in cultivating AF-MSCs. Considering its easy access, PRP may provide a valuable tool in multiple therapeutic approaches.  相似文献   
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