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31.
Influence of large molecular polymeric pigments (LMPP) isolated from fermented Zijuan tea on the activity and mRNA expression of key enzymes involved in lipid metabolism in rat was explored. The results show that intragastric infusion of high-dose LMPP (1.215g/kg body weight) effectively suppressed the elevation in TC and LDL-C (p<0.05), and prevented the reduction in HDL-C (p<0.05), compared with the hyperlipidemia model group. LMPP significantly enhanced the activity of HL and HSL, and increased the HSL mRNA expression in the liver tissue and adipose tissue. High-LMPP treatment significantly reduced the HMG-CoA reductase expression by 56.5% in the liver compared with hyperlipidemia model group. In contrast, LDL-R expression was increased by 120% in the presence of high-LMPP treatment. These results suggest that LMPP have the hypolipidemic effect to some extent and significantly enhance HSL mRNA expression in the liver and adipose tissue, thereby increasing HSL activity in rat.  相似文献   
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33.

Background and aims

The role of lipoprotein (a) [Lp(a)] in coronary artery diseases (CAD) with special clinical background such as type 2 diabetes mellitus (T2DM) has not been fully determined. The aim of the present study was to investigate the relation of Lp(a) to type 2 diabetic patients with or without CAD.

Methods and results

A total of 2040 consecutive patients with T2DM who received selective coronary angiography (CAG) due to angina-like chest pain were enrolled. The patients were subsequently divided into CAD and non-CAD groups according to the results of CAG. The severity of CAD was evaluated by the Gensini Score (GS), number of stenotic vessels, and history of myocardial infarction (MI). Data showed that Lp(a) levels were higher in the CAD group than in the non-CAD group (median: 15.00 mg/dL vs. 11.88 mg/dL, P = 0.025). The results from CAD subgroup analysis indicated that the patients with MI, multiple-vessel disease and high GS had higher Lp(a) levels compared with those in their matched subgroups (P < 0.05, respectively). After adjustment for confounders, Lp(a) levels were independently related to the presence and severity of CAD (CAD:OR = 1.564; MI:OR = 1.523; high GS:OR = 1.388; multiple-vessel disease:OR = 1.455; P < 0.05, respectively).

Conclusion

Elevated Lp(a) levels were independently associated with the presence and severity of CAD in patients with T2DM. More studies are necessary to confirm our findings.  相似文献   
34.
Background and aimsThe Mediterranean diet has been recognised as having a protective role on the cardiovascular system due to its low lipid and high antioxidant content. Lipid profile and oxidant status represent two important risk factors related to endothelial dysfunction, even at early stages of cardiovascular diseases. The aim of the study was to evaluate the influence of a 12-month Mediterranean diet on the variation of lipid profile and carotid intima–media thickness (cIMT) in pre-pubertal hypercholesterolaemic children.Methods and resultsWe performed a cross-sectional study comparing lipid profile and cIMT in a group of 68 pre-pubertal children (36 with hypercholesterolaemia and 32 controls). In addition, in the hypercholesterolaemic children a 12-month intervention programme with a Mediterranean diet was started to evaluate the variation of lipid profile and cIMT. At baseline, hypercholesterolaemic children showed a significantly higher cIMT (both right and left carotid artery) compared to controls (both p < 0.05). After 12 months of diet intervention, a significant reduction of total cholesterol, LDL-cholesterol and cIMT was documented (all p < 0.05). Furthermore, at the end of follow-up, delta body mass index-Standard Deviation score and delta LDL-cholesterol were significantly and independently related to the changes of cIMT (both p < 0.05).ConclusionThe Mediterranean diet represents a valid approach in the treatment of hypercholesterolaemia even during childhood.  相似文献   
35.
Background and aimsKiwifruit has the potential to improve markers of metabolic dysfunction, but the response may be influenced by inflammatory state. We aimed to investigate whether inflammatory state would modulate the effect of consuming two green kiwifruit daily on plasma lipids and markers of inflammation.Methods and resultsEighty-five hypercholesterolaemic men completed a 4-week healthy diet run-in, before randomisation to a controlled cross-over study of two 4-week interventions of two green kiwifruit/day plus healthy diet (intervention) or healthy diet alone (control). Anthropometric measures and fasting blood samples (plasma lipids, serum apolipoproteins A1 and B, high-sensitivity C-reactive protein (hs-CRP) and interleukin (IL)-6, tumour necrosis factor-alpha (TNF-α) and IL-10) were taken at baseline, 4 and 8 weeks. Subjects were divided into low and medium inflammatory groups, using pre-intervention hs-CRP concentrations (hs-CRP <1 and 1–3 mg/L, respectively).In the medium inflammatory group the kiwifruit intervention resulted in significant improvements in plasma high-density lipoprotein cholesterol (HDL-C) (mean difference 0.08 [95% CI: 0.03, 0.12] mmol/L [P < 0.001]), total cholesterol (TC)/HDL-C ratio (−0.29 [−0.45, −0.14] mmol/L [P = 0.001]), plasma hs-CRP (−22.1 [−33.6, −4.97]% [P = 0.01]) and IL-6 (−43.7 [−63.0, −14.1]% [P = 0.01]) compared to control treatment. No effects were seen in the low inflammatory group. There were significant between inflammation group differences for TC/HDL-C (P = 0.02), triglyceride (TG)/HDL-C (P = 0.05), and plasma IL-6 (P = 0.04).ConclusionsInflammatory state modulated responses to the kiwifruit intervention by improving inflammatory markers and lipid profiles in subjects with modestly elevated CRP, suggesting this group may particularly benefit from the regular consumption of green kiwifruit.Registered 16th March 2010, Australian New Zealand Clinical Trials Registry (no. ACTRN12610000213044), www.ANZCTR.org.au.  相似文献   
36.
Titanium alloys are extensively employed in the fabrication of various aviation structural parts, of which the most crucial processing step is hot working. In order to study the high-temperature deformation behavior of the TC21 titanium alloy, high-temperature tensile tests were performed. The results reveal that the flow stress of the material gradually decreases with an increased strain rate, and the stress increases rapidly with an increase in strain during the deformation of the alloy. Following this, flow stress gradually decreases. Flow stress decreases sharply, and the sample fractures when the appearance of necking and microvoids is observed. The Arrhenius and Radial basis function (RBF) neural network constitutive models are established in order to accurately describe the high-temperature deformation behavior of the material. In the modified Arrhenius model, strain rate indexes are expressed as a function of deformation temperature and strain rates; furthermore, the high prediction ability of the model was obtained. For the Radial basis function, the network parameters were obtained using the trial-and-error method. The established models could better forecast the flow stress of materials, and highly accurate results are obtained using the radial basis function model. The relationships between the stress index and the deformation activation energy with strain indicate that the primary deformation mechanism involves grain boundary slip and viscous slip of dislocations. The process of dynamic recrystallization primarily promotes the softening of the material.  相似文献   
37.
目的 :探讨氟伐他汀对老年原发性高胆固醇血症 (PHC)的疗效、安全性及耐受性。方法 :采用随机双盲平行对照法 ,将 82例老年PHC病人分成氟伐他汀组 (试验组 ) 42例和安慰剂组 (对照组 ) 40例 ,氟伐他汀 2 0mg/d~ 40mg/d ,治疗 12周后观察疗效和安全性。结果 :用药 12周后血清总胆固醇(TC )、低密度脂蛋白胆固醇(LDL -C)、三酰甘油 (TG)结果升高 ,两组较治疗前均值下降率比较有统计学意义 (P <0 .0 5~ 0 .0 1) ,两组副反应发生率分别为 7.5 %和5 .1% (P >0 .0 5 ) ,主要表现为胃肠道症状 ,均可耐受。结论 :服用氟伐他汀 2 0mg/d~ 40mg/d治疗老年PHC ,能明显降低TC、TG、LDL -C ,升高HDL -C ,且安全性好 ,易于耐受。  相似文献   
38.

Aims

This study aimed to evaluate the association between baseline bilirubin (TBiL) and follow-up TBiL changes for diabetic kidney disease (DKD) incidence and progression based on a 5?years' cohort study.

Methods

This cohort study was conducted in Beijing between 2009 and 2013. The subjects were consisted of 5342male diabetic patients with baseline retinopathy. Cox proportional risk model was used to calculate hazards ratio (HR).

Results

The mean age of the 5342 diabetic patients was 78.68?±?8.40 (65–102?yrs). The total five year incidence was 8.7% (95%CI: 7.9%–9.4%) for DKD and 10.5% (95%CI: 9.7%–11.3%) for eGFR decrease. The HR of baseline TBiL showed a decreasing trend for both DKD incidence and eGFR decrease. The HRs of baseline TBiL (per μmol/L increase) for DKD and eGFR decrease were 0.967(95%CI: 0.946–0.988) and 0.955(95%CI: 0.936–0.975) respectively. For follow-up TBiL changes, after adjusted for related co-variables and baseline TBiL levels (as continuous variable) in the model, the HRs (per μmol/L of follow-up TBiL changes) for DKD and eGFR decrease were 0.973(95%CI: 0.952–0.995) and 0.991(95%CI: 0.974–0.998) respectively. The results were similar when baseline TBiL and follow-up TBiL changes were used as tertiary variable.

Conclusion

Not only baseline TBiL, but also follow-up changes were significantly associated with DKD incidence and progression.  相似文献   
39.

Objective

The aim of this study was to investigate the metabolic risk factors for fatty liver disease in the elderly, and determine the prevalence of fatty liver disease in the elderly in Wuhan, central China.

Methods

The study was a case–control study based on all 4226 adults above 60 years of age from a cohort investigated in 2010–11 at the medical examination center of Zhongnan hospital, using 3145 randomly selected adults under 60 years of age from the same cohort as controls. Fatty liver disease (FLD) was identified with ultrasound imaging. The risk factors measured were body mass index (BMI), and plasma concentrations of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL), low density lipoprotein (LDL) and serum uric acid (SUA). The probability of steatohepatitis with advanced fibrosis was predicted using a score based on BMI, age, ALT, and TG (BAAT),and using AST/ALT ratio (AAR).

Results

FLD was higher in the elderly (26.7%) than in the non-elderly (22.8%) and similar in the elderly between men and women (26.6% vs 27.0%, p > 0.05). BMI, TC, TG, LDL, SUA, AST and ALT were all significantly higher in FLD, whereas the level of HDL was markedly lower. Multiple regression analyses showed that obesity, high TC, TG, SUA, low HDL, and elevated ALT, AAR < 1 were closely related to the elderly FLD, while male sex, obesity, high TC, TG, low HDL, elevated ALT, AST and AAR < 1 were closely related to the non-elderly FLD. The prevalence of steatohepatitis with advanced fibrosis estimated as BAAT index ≥ 3 was 2.4% in all subjects, and was higher in the elderly FLD patients than in the non-elderly FLD patients.

Conclusion

The prevalence of FLD is higher in the elderly, and is broadly related to the same metabolic risk factors as in the non-elderly. However, female-sex is no longer protective with increasing age, and the prevalence of steatohepatitis with advanced fibrosis is estimated to be considerably higher in the elderly FLD patients than in the non-elderly FLD controls.  相似文献   
40.
目的 研究乙型肝炎病毒核心蛋白c/el表位处TC标签的基因标记对S和e抗原表达的影响,探索TC标签标记HBV病毒体的可行性.方法 以含有1.3倍HBV基因组的载体为模板,在HBV C基因中插入编码TC标签的碱基序列,得到重组的突变型HBV载体,其编码的核心蛋白的c/el表位处嵌入了TC标签.将野生型和突变型HBV载体分别瞬时转染HepG2细胞,Westernblot检测野生型和各种TC嵌合型核心蛋白的表达,酶联免疫吸附法分析病毒S和e抗原的表达.多组间比较用单因素方差分析.结果 Western blot显示各种嵌合型核心蛋白在细胞内成功表达,并且同野生型蛋白的表达水平无显著差别,酶联免疫吸附法检测表明各组细胞S和e抗原表达水平没有明显差别.结论 HBV核心蛋白c/el表位处TC标签的基因标记不会明显影响突变HBV载体表达病毒蛋白.  相似文献   
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