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31.
32.

Background

The TIMI Score for ST-segment elevation myocardial infarction (STEMI) was created and validated specifically for this clinical scenario, while the GRACE score is generic to any type of acute coronary syndrome.

Objective

Between TIMI and GRACE scores, identify the one of better prognostic performance in patients with STEMI.

Methods

We included 152 individuals consecutively admitted for STEMI. The TIMI and GRACE scores were tested for their discriminatory ability (C-statistics) and calibration (Hosmer-Lemeshow) in relation to hospital death.

Results

The TIMI score showed equal distribution of patients in the ranges of low, intermediate and high risk (39 %, 27 % and 34 %, respectively), as opposed to the GRACE Score that showed predominant distribution at low risk (80 %, 13 % and 7%, respectively). Case-fatality was 11%. The C-statistics of the TIMI score was 0.87 (95%CI = 0.76 to 0.98), similar to GRACE (0.87, 95%CI = 0.75 to 0.99) - p = 0.71. The TIMI score showed satisfactory calibration represented by χ2 = 1.4 (p = 0.92), well above the calibration of the GRACE score, which showed χ2 = 14 (p = 0.08). This calibration is reflected in the expected incidence ranges for low, intermediate and high risk, according to the TIMI score (0 %, 4.9 % and 25 %, respectively), differently to GRACE (2.4%, 25% and 73%), which featured middle range incidence inappropriately.

Conclusion

Although the scores show similar discriminatory capacity for hospital death, the TIMI score had better calibration than GRACE. These findings need to be validated populations of different risk profiles.  相似文献   
33.
34.

Background

More data on the risk factors and outcomes after Staphylococcus aureus infections in liver transplantation are needed.

Methods

Liver recipients with S. aureus infections (cases) were retrospectively identified and compared to gender-, age-, and transplant type-matched (1:2) non-S. aureus-infected controls. Risk factors associated with S. aureus infections were identified by conditional logistic regression analysis.

Results

We evaluated 51 patients (median age 52?years). First S. aureus infections developed at a median time of 29?days after transplantation, with 52.94% of them in the first month; 88.24% were nosocomial, 41.18% were polymicrobial, and 47.06% were caused by methicillin-resistant S. aureus (MRSA). Surgical site infections represented 58.82% and bacteremia 23.53%. By univariate analysis, patients with S. aureus infections were intubated more frequently (odds ratio [OR] 26.92, 95% confidence interval [CI] 3.23?C3,504.15, p?=?0.0006), had a central line (OR 11.69, 95% CI 1.42?C95.9, p?=?0.02), or recent surgery (OR 26.92, 95% CI 3.23?C3,504.15, p?=?0.0006) compared with controls. By multivariate analysis, subjects who underwent surgery within 2?weeks prior to infection had a 26.9 times higher risk of developing S. aureus infection (95% CI 3.23?C3,504.15, p?=?0.0006); these results were adjusted for matched criteria. S. aureus infections did not affect graft or patient survival, but the study was not powered for such outcomes.

Conclusion

Only recent surgical procedure was found to be a significant independent risk factor for S. aureus infections after liver transplantation.  相似文献   
35.
Obesity markedly increases the risk of hypertension and cardiovascular disease, which may be related to activation of the sympathetic nervous system (SNS). Sympathetic overactivity directly and indirectly contributes to blood pressure (BP) elevation in obesity, including stimulation of the renin-angiotensin-aldosterone system (RAAS). The adipocyte-derived peptide leptin suppresses appetite, increases thermogenesis, but also raises SNS activity and BP. Obese individuals exhibit hyperleptinemia but are resistant to its appetite-suppressing actions. Interestingly, animal models of obesity exhibit preserved sympathoexcitatory and pressor actions of leptin, despite resistance to its anorexic and metabolic actions, suggesting selective leptin resistance. Disturbance of intracellular signaling at specific hypothalamic neural networks appears to underlie selective leptin resistance. Delineation of these pathways should lead to novel approaches to treatment. In the meantime, treatment of obesity-hypertension has relied on antihypertensive drugs. Although sympathetic blockade is mechanistically attractive in obesity-hypertension, in practice its effects are disappointing because of adverse metabolic effects and inferior outcomes. On the basis of subgroup analyses of obese patients in large randomized clinical trials, drugs such as diuretics and RAAS blockers appear superior in preventing cardiovascular events in obesity--hypertension. An underused alternative approach to obesity-hypertension is induction of weight loss, which reduces circulating leptin and insulin, partially reverses resistance to these hormones, decreases sympathetic activation and improves BP and other risk factors. Though weight loss induced by lifestyle is often modest and transient, carefully selected pharmacological weight loss therapies can produce substantial and sustained antihypertensive effects additive to lifestyle interventions.  相似文献   
36.
Posterior reversible encephalopathy syndrome (PRES) is a clinicoradiologic entity not yet understood, that is present with transient neurologic symptoms and particular radiological findings. The most common imaging pattern in PRES is the presence of edema in the white matter of the posterior portions of both cerebral hemispheres. The cause of PRES is unclear. We report a case of 13‐year‐old male who was stung by a scorpion and developed a severe headche, visual disturbance, and seizures and had the diagnosis of PRES with a good outcome. Numerous factors can trigger this syndrome, most commonly: acute elevation of blood pressure, abnormal renal function, and immunosuppressive therapy. There are many cases described showing the relationship between PRES and eclampsia, transplantation, neoplasia and chemotherapy treatment, systemic infections, renal disease acute, or chronic. However, this is the first case of PRES following a scorpion sting.  相似文献   
37.
38.
Ewing sarcoma is a highly malignant tumor of bone preferentially arising in children and young adults. Its 5-year survival rate is only 50% despite the use of multimodal therapeutic approaches, requiring a search for new therapeutic targets and the development of novel therapeutic modalities. KIT and PDGFRs are type III receptor tyrosine kinases, and activating mutations in c-kit (which encodes KIT) and PDGFRs have been reported as oncogenic events in many malignancies. Imatinib is a selective inhibitor of KIT, PDGFR, and ABL tyrosine kinase activity and exerts different anti-tumor effects according to the regions of mutations in c-kit and PDGFR genes. Thus, we evaluated the immunohistochemical expression of KIT protein and the mutational status of exons 9, 11, 13, and 17 of the c-kit gene, exons 12 and 18 of the PDGFRA gene, and exon 12 of the PDGFRB gene in 71 formalin-fixed, paraffin-embedded Ewing sarcomas to increase our understanding of the potential, if any, of imatinib treatment for this malignancy. Of the 71 samples, 27 (38%) were immunohistochemically positive for KIT; however, activating mutations in c-kit were found in only 2 of 71 Ewing sarcomas (2.6%) within exon 9. No activating mutations in the PDGFRA and PDGFRB genes were found, but pleomorphism was identified in exon 18 of the PDGFRA gene. Our results for KIT protein expression agree with those of previous studies. This is the largest series of c-kit mutational analysis in Ewing sarcoma to date, and the results definitively show that c-kit activating mutations are not coincident with KIT protein expression in Ewing sarcoma in most samples. These findings imply other mechanisms for KIT activity and leave open the question of whether imatinib would be efficacious in the treatment of Ewing sarcoma.  相似文献   
39.
40.
Lasers in Medical Science - The benefits of photobiomodulation (PBM) applied to wounds are well-described in the literature; however, its effects in skin graft donor sites have been poorly studied....  相似文献   
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