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71.
72.

Objective

To determine if the prevalence of diastolic dysfunction is increased in rheumatoid arthritis (RA) patients.

Methods

We conducted a time‐ and language‐restricted literature search to identify studies conducted to compare echocardiographic parameters in patients with RA and controls. The mean difference for echocardiographic variables of interest was calculated using a random‐effects model. A systematic review of the literature was performed.

Results

A total of 25 studies reporting on 5,836 subjects (1,614 with RA) were included. Results reflect mean differences, with positive values denoting higher values in RA patients. Patients with RA had larger mean left atrial dimension (mean difference 0.09 cm [95% confidence interval (95% CI) 0.01, 0.17]; P = 0.02), higher left ventricular mass index (mean difference 6.2 gm/m2 [95% CI 1.08, 11.33]; P = 0.02), higher mean systolic pulmonary artery pressure (mean difference 5.87 mm Hg [95% CI 4.36, 7.38]; P < 0.00001), prolonged isovolumetric relaxation time (mean difference 9.67 msec [95% CI 5.78, 13.56]; P < 0.00001), and higher transmitral A wave velocity (mean difference 0.13 meters/second [95% CI 0.07, 0.18]; P < 0.00001) compared to controls. A subanalysis of 2,183 subjects excluding 2 large unmatched studies showed the same results, with the exception that patients with RA had a lower mitral E/A ratio (mean difference ?0.17 [95% CI ?0.25, ?0.09]; P < 0.00001), suggestive of diastolic dysfunction. There were no differences in left ventricular ejection fraction (%), transmitral E wave velocity (meters/second), and mitral deceleration time (msec).

Conclusion

Patients with RA were more likely to have echocardiographic parameters of diastolic dysfunction, and have higher systolic pulmonary artery pressures and larger left atrial sizes.
  相似文献   
73.
Kelley GL  Allan G  Azhar S 《Endocrinology》2004,145(2):548-555
High-fructose feeding causes diet-induced alterations of lipid metabolism and decreased insulin sensitivity with alterations of hepatic pyruvate dehydrogenase and hepatic very low-density lipoprotein secretion. Inflammatory cytokines also induce dramatic changes in lipid metabolism, particularly in serum triglycerides via increased hepatic secretion and/or delayed clearance of very low-density lipoprotein. The aim of this study was to determine whether the mechanism of lipid dysregulation in the high-fructose diet is induced by stress response pathways. Animals were fed a high-fructose diet for 14 d to establish hypertriglyceridemia and then were treated with lipoxygenase inhibitors for 4 d concurrent with the diet. At the end of drug treatment, the animals were divided into two groups and treated with lipopolysaccharide or a vehicle. Serum samples were taken pretreatment and posttreatment, and liver tissue was harvested at the end of study. Serum samples were tested for metabolic parameters, and the tissue samples were tested for metabolic and stress pathway responses. Our results show that fructose-fed rats have changes in the c-Jun N-terminal kinase pathway with correspondingly elevated activator protein-1 activity, consistent with an inflammatory response. Treatment with lipoxygenase inhibitors reversed the hypertriglyceridemia and also reduced activator protein-1 activation, suggesting that the basis for lipid dysregulation in this model is due to activation of inflammatory pathways in the liver.  相似文献   
74.
Sympathetic skin response (SSR) in erythromelalgia   总被引:2,自引:0,他引:2  
BACKGROUND: Erythromelalgia (EM) is characterized by severe pain associated with local redness and hotness in the extremities. When the extremity is lowered, or heat is applied, the pain is intensified and when coldness is applied, or the extremity is elevated the pain is decreased. OBJECTIVE: To evaluate if there is any sympathetic nervous system involvement in erythromelalgia, sympathetic skin response (SSR) test was done. SETTING: This study was conducted during the years 1998-2000 in the Department of Physical medicine and Rehabilitation, Shiraz University of Medical Sciences. METHODS: SSR study was done on 22 patients with erythromelalgia and 22 normal subjects were matched for age and sex for comparison. RESULTS: There is a significant difference between the patients and controls especially in the lower extremity findings (P = 0.000). More than 72.7% of the patients had abnormal SSR. CONCLUSION: It is concluded that sympathetic peripheral fibers (C fibers) are involved in erythromelalgia and it is probably the pathogenesis of the disease.  相似文献   
75.
Viral diseases like influenza, AIDS, hepatitis, and Ebola cause severe epidemics worldwide. Along with their resistant strains, new pathogenic viruses continue to be discovered so creating an ongoing need for new antiviral treatments. RNA interference is a cellular gene‐silencing phenomenon in which sequence‐specific degradation of target mRNA is achieved by means of complementary short interfering RNA (siRNA) molecules. Short interfering RNA technology affords a potential tractable strategy to combat viral pathogenesis because siRNAs are specific, easy to design, and can be directed against multiple strains of a virus by targeting their conserved gene regions. In this review, we briefly summarize the current status of siRNA therapy for representative examples from different virus families. In addition, other aspects like their design, delivery, medical significance, bioinformatics resources, and limitations are also discussed.  相似文献   
76.
77.
Allogeneic hematopoietic stem cell transplantation (alloHCT) is offered increasingly to elderly patients with hematologic malignancies. However, outcome data in those who are 70 years or older are limited, and no standard conditioning regimen has been established for this population. In this retrospective study we evaluated the outcome of 53 consecutive patients aged 70 years and older who underwent alloHCT with melphalan-based reduced-intensity conditioning (RIC) at City of Hope. Engraftment was prompt, with median time to neutrophil engraftment of 15 days. More than 95% of patients achieved complete donor chimerism within 6 weeks from HCT, consistent with the “semiablative” nature of this regimen. With a median follow-up of 31.1 months, the 2-year overall survival (OS), progression-free survival (PFS), and nonrelapse mortality (NRM) were 68.9%, 63.8%, and 17.0%, respectively. Cumulative incidence of relapse at 1 and 2 years was 17.0% and 19.3%, respectively. One hundred–day cumulative incidence of grades II to IV acute graft-versus-host disease was 37.7% (grades III to IV, 18.9%), and 2-year cumulative incidence of chronic graft-versus-host disease was 61.9% (extensive, 45.9%). The only significant predictor for poor OS was high/very high disease risk index. Transplant-related complications and morbidities observed here did not differ from the commonly expected in younger patients treated with RIC. In conclusion, alloHCT with a melphalan-based conditioning regimen is associated with acceptable toxicities and NRM, lower incidence of relapse, and favorable OS and PFS in patients aged 70 years or older.  相似文献   
78.

Objective

To evaluate the effects of growth hormone (GH) as an antioxidant and tissue-protective agent and analyse the biochemical and histopathological changes in rat ovaries due to experimental ischemia and ischemia/reperfusion injury.

Study design

Forty-eight adult female rats were randomly divided into eight groups. In Group 1, a period of bilateral ovarian ischemia was applied. In Groups 2 and 3, 1 and 2 mg/kg of GH was administered, and 30 min later, bilateral ovarian ischemia was applied (after a 3-h period of ischemia, both ovaries were surgically removed). Group 4 received a 3-h period of ischemia followed by 3 h of reperfusion. Groups 5 and 6 received 1 and 2 mg/kg of GH, respectively, 2.5 h after the induction of ischemia. At the end of a 3-h period of ischemia, bilateral vascular clips were removed, and 3 h of reperfusion continued. Group 7 received a sham operation plus 2 mg/kg of GH. Group 8 received a sham operation only. After the experiments, superoxide dismutase and myeloperoxidase activity and levels of glutathione and lipid peroxidation were determined, and histopathological changes were examined in all rat ovarian tissue.

Results

Ischemia and ischemia/reperfusion decreased superoxide dismutase activity and glutathione levels in ovarian tissue, but increased lipid peroxidation levels and myeloperoxidase activity significantly in comparison to the sham group. The 1 and 2 mg/kg doses of GH before ischemia and ischemia/reperfusion decreased lipid peroxidation levels and myeloperoxidase activity in the experimental groups. The administration of GH before ischemia and ischemia/reperfusion treatments also increased superoxide dismutase and glutathione levels. The histopathological findings also suggested a protective role of GH in ischemia/reperfusion injury. That is, ovarian tissues in the ischemia groups showed histopathological changes, such as haemorrhage, cell degeneration, and necrotic and apoptotic cells, but these changes in the GH groups were lesser. Moreover, in the ischemia/reperfusion groups, acute inflammatory processes - such as neutrophil adhesion and migration, apoptotic and degenerative cells, stromal oedema and haemorrhage - were present. However, the ovarian tissues of the IR + GH (1 mg) group had minimal apoptotic cells, and the IR + GH (2 mg) group had no apoptotic cells. In addition, the general ovarian histological structures of these groups were similar to those of the healthy control group.

Conclusions

The administration of GH is protective against ischemia and/or ischemia/reperfusion-induced ovarian damage. This protective effect can be attributed to the antioxidant properties of GH.  相似文献   
79.
To examine the influence of diabetes education on well-being, 255 patients with type 2 diabetes were recruited according to whether they attended a diabetes education program (n=126) or not (n=129). In patients who had participated in the program, the mean anxiety score was significantly lower, whereas positive well-being and general well-being scores were significantly higher than for patients who had not participated. Factors related to lower well-being included: being female, taking insulin, not attending a diabetes education program and having HbA(1c) level greater than 8%. The odds of having better well-being were two-fold higher in patients participating the diabetes education program compared with those who had not. Diabetes education has a crucial role in improving the well-being of patients with type 2 diabetes. All patients with diabetes should be encouraged to attend a diabetes education program.  相似文献   
80.
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