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Assessment of mitral regurgitant jets by three-dimensional color Doppler   总被引:1,自引:0,他引:1  
BACKGROUND: Color Doppler echocardiography is a standard technique for assessing mitral regurgitation before and after mitral valvuloplasty. Mitral valve prolapse produces complex eccentric jet flows that cannot be visualized and measured by two-dimensional color Doppler echocardiography. The aim of this study was to evaluate the clinical impact of three-dimensional color Doppler echocardiography, a new technique developed at our institution, for assessing mitral regurgitation. METHODS: Forty-five patients with mitral regurgitation underwent intraoperative transesophageal echocardiography and three-dimensional Doppler data acquisition. The grade of mitral regurgitation was assessed by angiography. The jet areas were calculated by planimetry from conventional color Doppler; the jet volumes were obtained by three-dimensional Doppler data. RESULTS: New patterns of mitral regurgitant flows were recognized according to the origin, direction, and spatial spreading into the left atrium. Conventional jet areas failed to separate the groups of patients with different degrees of regurgitation, whereas the jet volumes were able to divide patients with different regurgitation grades. No significant correlation was found between jet area and angiographic grading (r = 0.63, p = NS). Jet volumes were significantly correlated to angiography (r = 0.89, p < 0.001). CONCLUSIONS: Three-dimensional color Doppler echocardiography revealed new patterns of regurgitant flow and allowed a more accurate semiquantitative assessment of complex asymmetrical regurgitant jets.  相似文献   
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Brain death impairs coronary endothelial function   总被引:4,自引:0,他引:4  
Szabo G  Buhmann V  Bahrle S  Vahl CF  Hagl S 《Transplantation》2002,73(11):1846-1848
BACKGROUND: To characterize the impact of brain death (BD) on endothelial dysfunction after cardiac transplantation we investigated coronary circulation and vasomotor function in a canine model. METHODS: Left ventricular pressure-volume data (conductance catheter) and coronary blood flow (CBF) were monitored continuously. Endothelium-dependent vasodilatation after acetylcholine and endothelium-independent vasodilation after sodium nitroprusside were assessed before and 3 hr after BD induction (inflation of a subdural balloon). RESULTS: BD led to an initial hyperdynamic reaction with significant (P<0.05) increase of CBF. After 3 hr, CBF decreased significantly (P<0.05). Although before BD, application of acetylcholine led to a monophasic vasodilatative response, after BD a short mild vasodilatation was followed by a longer vasoconstriction. Endothelium-independent vasodilatation remained unchanged. CONCLUSIONS: BD affects coronary circulation by two means: (1) impairment of CBF to decrease in parallel in afterload with consecutive hemodynamic deterioration and (2) severe endothelial dysfunction that may be a contributing factor to posttransplant outcome.  相似文献   
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We evaluated the long-term outcome of patients with an osteosarcoma who had undergone prior manipulative therapy, a popular treatment in Asia, and investigated its effects on several prognostic factors. Of the 134 patients in this study, 70 (52%) patients had manipulative therapy and 64 (48%) did not. The age, location, and size of tumour were not significantly different between the groups. The five-year overall survival rate was 58% and 92% in the groups with and without manipulative therapy (p = 0.004). Both the primary and overall rates of lung metastasis were significantly higher in the manipulative group (primary: 32% vs 3%, p = 0.003; overall lung metastasis rate: 51.4% vs 18.8%, p < 0.001). Patients who had manipulative therapy had higher local recurrence rates in comparison to patients who did not (29% vs 6%, p = 0.011). The prognosis for patients with osteosarcoma who had manipulative therapy was significantly poorer than those who had not. Manipulative therapy was an independent factor for survival. This form of therapy may serve as a mechanism to accelerate the spread of tumour cells, and therefore must be avoided in order to improve the outcome for patients with an osteosarcoma.  相似文献   
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Neurological symptoms of tuberculosis are rare, even if there this pathology has been on the rise for a number of years because of HIV. Intramedullary tuberculoma is an exceptional location. We report the case of a patient with no HIV or immunodepression symptoms with intramedullary tuberculoma, revealed by a clinical presentation of insidious onset of myelopathy. We will discuss the diagnosis, treatment and clinical functional follow-up. The optimal treatment seems to be a combination of microsurgical resection and antibiotic therapy.  相似文献   
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Purpose

The aim of this study was to evaluate risk factors for an acute cellular rejection episode (ARE) among adult liver transplant (OLT) patients.

Materials and methods

We retrospectively reviewed 110 consecutive patients who underwent OLT between May 2007 and December 2010. The diagnosis of ARE was based upon clinical and biochemical data; liver biopsy was only performed when clinical presentation was equivocal. We recorded donor and recipient characteristics, perioperative immune status, and postoperative laboratory data. Forty patients (36.4%) who suffered a clinical rejection episode and received pulsed or recycled steroid therapy (R group), were compared with 70 (63.6%) free of rejection (N group).

Results

The mean age of R recipients was 46.61 ± 9.97 years, which was younger than the N group (51.86 ± 8.37, P = .005). R group patients displayed a lower pre-OLT creatinine (P = .016) and higher alanine aminotransferase (P = .048). Cox regression model showed recipient age to be the only significant factor to predict ARE (odds ratio = 1.071, P = .003). The cutpoint of age was 46 years by receiver operating characteristic analysis. Patients younger than 46 years showed higher initial CD8+ T-cell counts (P = .038).

Conclusion

Recipient age was significantly associated with ARE; younger patients showed higher CD8+ lymphocyte counts than older patients. More aggressive immunosuppression should be considered for younger recipients to prevent ARE.  相似文献   
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Thoracic endovascular aortic repair (TEVAR) has emerged as a promising therapeutic alternative to conventional open aortic replacement but it requires suitable proximal and distal landing zones for stent-graft anchoring. Many aortic pathologies affect in the immediate proximity of the left subclavian artery (LSA) limiting the proximal landing zone site without proximal vessel coverage. In patients in whom the distance between the LSA and aortic lesion is too short, extension of the landing zone can be obtained by covering the LSA's origin with the endovascular stent graft (ESG). This manoeuvre has the potential for immediate and delayed neurological and vascular symptoms. Some authors, therefore, propose prophylactic revascularisation of the LSA by transposition or bypass, while others suggest prophylactic revascularisation only under certain conditions, and still others see no requirement for prophylactic revascularisation in anticipation of LSA ostium coverage. In this review about LSA revascularisation in TEVAR patients with coverage of the LSA, we searched the electronic databases MEDLINE and EMBASE historically until the end date of May 2010 with the search terms left subclavian artery, covering, endovascular, revascularisation and thoracic aorta. We have gathered the most complete scientific evidence available used to support the various concepts to deal with this issue. After a review of the current available literature, 23 relevant articles were found, where we have identified and analysed three basic treatment concepts for LSA revascularisation in TEVAR patients (prophylactic, conditional prophylactic and no prophylactic LSA revascularisation). The available evidence supports prophylactic revascularisation of the LSA before ESG LSA coverage when preoperative imaging reveals abnormal supra-aortic vascular anatomy or pathology. We further conclude that elective patients undergoing planned coverage of the LSA during TEVAR should receive prophylactic LSA transposition or LSA-to-left-common-carotid-artery (LCCA) bypass surgery to prevent severe neurological complications, such as paraplegia or brain stem infarction.  相似文献   
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