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51.
Early life experience differentially shapes later stress reactivity, as evidenced by both animal and human studies. However, early experience-related changes in the function of central visceral neural circuits that control stress responses have not been well characterized, particularly in humans. The paraventricular nucleus of the hypothalamus (PVN), bed nucleus of the stria terminalis (BNST), amygdala (Amyg) and subgenual anterior cingulate cortex (sgACC) form a core visceral stress-responsive circuit. The goal of this study is to examine how childhood emotional and physical abuse relates to adulthood stressor-evoked activity within these visceral brain regions. To evoke acute states of mental stress, participants (n = 155) performed functional magnetic resonance imaging (fMRI)-adapted versions of the multi-source interference task (MSIT) and the Stroop task with simultaneous monitoring of mean arterial pressure (MAP) and heart rate. Regression analyses revealed that childhood physical abuse correlated positively with stressor-evoked changes in MAP, and negatively with unbiased, a priori extractions of fMRI blood-oxygen level-dependent signal change values within the sgACC, BNST, PVN and Amyg (n = 138). Abuse-related changes in the function of visceral neural circuits may reflect neurobiological vulnerability to adverse health outcomes conferred by early adversity.  相似文献   
52.

Aim

To investigate the effect of changes in fasting plasma glucose (FPG) variability, as assessed by 2-year trajectories of FPG variability, on mortality risk in patients with type 2 diabetes (T2D).

Methods

From 2009 to 2012, outpatients with T2D, aged > 18 years, were enrolled from a medical centre. FPG was measured every 3 months for 2 years in 3569 people. For each of the eight 3-month intervals, FPG variability and means were calculated, with variability defined as the coefficient of variation of FPG. Also, trajectories of FPG variability and means were determined separately, using group-based trajectory analysis with latent class growth models. These models were fitted using the SAS Proc Traj procedure. The primary outcome was all-cause mortality, which was followed-up to the end of 2014.

Results

Five distinct trajectories of FPG variability (low, increasing, fluctuating, decreasing and high) and means (well controlled, stable control, worsening control, improving control and poor control) were established. The five trajectories of mean FPG were all associated with the same mortality risk. In contrast, in comparison to the low FPG variability trajectory, the fluctuating, decreasing and high variability trajectories all had significantly higher risks of mortality, with respective hazards ratios of 2.63 (95% CI: 1.40–4.93; P = 0.003), 2.78 (95% CI: 1.33–5.80; P = 0.007) and 4.44 (95% CI: 1.78–11.06; P = 0.001) after multivariable adjustment.

Conclusion

Changes in FPG variability were independently associated with increased mortality risk in patients with T2D.  相似文献   
53.
The serum HBsAg in 4 chronic HBsAg carrier patients with hepatocellular carcinoma (HCC) cleared within 4-38 months after surgical resection of their hepatic tumors. Two patients developed anti-HBs. During the follow-up period from 21 to 28 months after HBsAg clearance, none of the patients regained positive serum HBsAg. Two patients who had had tissue HBsAg present, exclusively in the tumor, showed quick HBsAg clearance after resection. The other 2 patients had a delayed HBsAg clearance. One had tissue HBsAg in both the tumor and nontumoral liver. Only 1 patient had tissue HBsAg in the liver, but not in the tumor. During the same period of observation of 323 chronic HBsAg carriers, who had a variety of histologically-verified chronic liver diseases and were followed for more than 6 months, only 1 cleared the antigen. The spontaneous HBsAg clearance in our HBsAg carriers (1/323) was significantly lower than that (4/64) of HBsAg-positive HCC patients with tumor resection, P less than 0.004. The mechanisms of HBsAg clearance in HCC patients after surgical resection of tumors are discussed.  相似文献   
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OBJECTIVE: This study was designed to evaluate the effects of rosiglitazone (ROS) on insulin sensitivity, beta-cell function, and glycaemic response to glucose challenge and meal in subjects with impaired glucose tolerance (IGT). METHODS: Thirty patients with IGT (ages between 30 and 75 years and BMI (body mass index) < or = 27 kg/m2) were randomly assigned to receive either placebo (n = 15) or ROS (4 mg/day) (n = 15). All participants underwent a 75-g oral glucose tolerance test (OGTT), meal test, and frequently sampled intravenous glucose tolerance test (FSIGT) before and after the 12-week treatment. RESULTS: After 12 weeks of ROS treatment, there were significant increases in total cholesterol (TC) (4.25 +/- 0.22 vs 4.80 +/- 0.17 mmol/l, P < 0.001), high-density lipoprotein cholesterol (HDL-C) (1.25 +/- 0.07 vs 1.43 +/- 0.06 mmol/l, P < 0.05), and low-density lipoprotein cholesterol (LDL-C) (2.70 +/- 0.15 vs 3.37 +/- 0.17 mmol/l, P < 0.05) without changes in triglyceride concentration, TC/HDL-C and LDL-C/HDL-C ratio. Although the acute insulin response (AIR) to intravenous glucose and disposition index (measured as the ability of pancreatic beta-cell compensation in the presence of insulin resistance) remained unchanged, the insulin sensitivity (SI) and glucose effectiveness (SG) were remarkably elevated (0.38 +/- 0.06 vs 0.54 +/- 0.09 x 10(-5) min(-1)/pmol, P < 0.05; 0.017 +/- 0.002 vs 0.021 +/- 0.001 min(-1), P < 0.05, respectively) in the ROS group. The glucose, insulin, and c-peptide areas under curve (AUC) in response to OGTT and the glucose and insulin AUC during meal were significantly ameliorated in the ROS group. Five out of 15 (33%) and two out of 15 (13%) subjects treated with ROS and placebo, respectively, reversed to normal response during OGTT (P < 0.05). CONCLUSION: Rosiglitazone treatment significantly improved insulin resistance and reduced postchallenge glucose and insulin concentrations in patients with impaired glucose tolerance without remarkable effects on beta-cell secretory function.  相似文献   
57.

Purpose

Myeloid differentiation-2 (MD-2) has been associated with endotoxin and inflammatory disorders because it can recognize lipopolysaccharide (LPS) binding and attenuate Toll-like receptor 4 (TLR4)-mediated signaling. However, its role in allergic inflammation has yet to be clarified. We examined whether single nucleotide polymorphisms (SNPs) in MD-2 promoter can affect MD-2 expression and aimed to clarify the relationship between Der p 2 allergy and SNPs of MD-2 promoter.

Methods

The function of SNPs of MD-2 promoter and the effects of cytokines and immunoglobulin on the secretion and mRNA expression were investigated in 73 allergic subjects with different MD-2 gene promoter variants. Peripheral blood mononuclear cells were cultured with or without LPS in the presence of Dermatophagoides pteronyssinus group 2 allergen (Der p 2), followed by mRNA extraction and cytokine expression analysis. The culture supernatants were collected for cytokine measurement.

Results

Patients with the MD-2 promoter SNPs (rs1809441/rs1809442) had increased mRNA expressions of MD-2, ε heavy chain of IgE (Cε), and interleukin (IL)-8; however, only MD-2 and IL-8 were further up-regulated after Der p 2 stimulation. Patients with SNPs of MD-2 promoter tended to have high levels of IL-1β, IL-6, IL-8, IL-10, and tumor necrosis factor (TNF)-α after Der p 2 and LPS stimulation. Increased secretions of IL-6, IL-8, and IL-10 were found to be up-regulated by Der p 2 stimulation, and an increased secretion of IFN-γ and decreased secretion of IL-4 were noted after LPS stimulation.

Conclusions

The high levels of proinflammatory cytokines secreted by Der p 2 were predetermined by MD-2 promoter SNPs (rs1809441/rs1809442). Through cytokine secretion by Der p 2 and LPS, these SNPs may serve as an indicator of the pathological phenotype of Der p 2-induced allergic inflammation.  相似文献   
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BackgroundCardiovascular dysfunction was associated with progression of renal function decline. This study was to assess whether combination of brachial-ankle pulse wave velocity (baPWV) and the ratio of brachial pre-ejection period (bPEP) to brachial ejection time (bET) was independently associated with progression of renal function decline.MethodsWe included 363 patients and classified them into four groups according to median values of bPEP/bET and baPWV. Groups 1, 2, 3, and 4 were patients with bPEP/bET and baPWV below the median, bPEP/bET above but baPWV below the median, bPET/bET below but baPWV above the median, and bPET/bET and baPWV above the median, respectively. The decline in renal function was assessed by the estimated glomerular filtration rate (eGFR) slope and the renal end points were defined as commencement of dialysis or ≥25% decline in eGFR. The relative risk of renal end points was analyzed by Cox regression method.ResultsThe eGFR slope was significantly associated with baPWV, bPEP/bET, and patients in groups 2, 3, and 4 (vs. group 1) (P < 0.006). Multivariate forward Cox regression analysis showed that high baPWV, high bPEP/bET, and patients in groups 2, 3, and 4 (vs. group 1) (P ≤ 0.047) were independent predictors of renal end points.ConclusionsOur results demonstrated higher baPWV and bPEP/bET were associated with faster renal function decline and adverse renal end points. Dividing patients into four groups using these two parameters might be useful in risk stratification for progression of renal function decline.American Journal of Hypertension 2012; doi:10.1038/ajh.2012.77.  相似文献   
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