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Occlusion of varicoceles wih detachable balloons   总被引:1,自引:0,他引:1  
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Patient participation in medical care and in decision-making is generally viewed as a precursor to positive health outcomes. Patient participation is not always possible or desirable, however, and not all patients want to take an active part in their own medical care. This study examines the degree to which physician-patient congruence in preference for patient involvement is related to self-reported satisfaction, adherence, and health. Results indicate that when patients and their doctors share similar beliefs about patient participation, patient outcomes tend to be more positive, with highest satisfaction found in cases in which both patient and physician desire more patient involvement.  相似文献   
107.
The aim of this study was to analyze the clinical characteristics of thoracic ossified ligamentum flavum (OLF) and to elucidate prognostic factors as well as effective surgical treatment modality. The authors analyzed 106 thoracic OLF cases retrospectively from January 1999 to December 2008. The operative (n = 40) and the non-operative group (n = 66) were diagnosed by magnetic resonance imaging (MRI) and/or computed tomography (CT) imaging. We excluded cases exhibiting ventral compressive lesions causing subarachnoid space effacement in thoracic vertebrae as well as those with a coexisting cervical compressive myelopathy. Those in the operative group were treated with decompressive laminectomy as well as resection of OLF. The preoperative neurologic status and postoperative outcomes of patients, as indicated by their modified Japanese Orthopedic Association (mJOA) scores and recovery rate (RR), Modic changes, the axial (fused or non-fused) and sagittal (omega or beak) configurations of OLF, and the ratios of the cross-sectional area (CSA) and anteroposterior diameter (APD) of the most compressed level were studied. The most commonly affected segment was the T10–11 vertebral body level (n = 49, 27.1%) and the least affected segment was the T7–8 level (n = 1, 0.6%). The ratios of the CSA in non-fused and fused types were 77.3 and 59.3% (p < 0.001). When Modic changes were present with OLF, initial mJOA score was found to be significantly lower than those without Modic change (7.62 vs. 9.09, p = 0.033). Neurological status improved after decompressive laminectomy without fusion (preoperative vs. last mJOA; 7.1 ± 2.01 vs. 8.57 ± 1.91, p < 0.001). However, one patient exhibited transient deterioration of her neurological status after surgery. In the axial configuration, fused-type OLF revealed a significant risk for a decreased postoperative mJOA score (0–7, severe and moderate) (Odds ratio: 5.54, χ2 = 4.41, p = 0.036, 95% CI: 1.014–30.256). The results indicated that the new categorization of axial-type of OLF is a helpful predictor of postoperative patient outcome and fused type was related with poor prognosis. In OLF cases free from ventral lesions compressing the spinal cord, decompressive laminectomy is enough for successful surgical outcome. Therefore, early surgical treatment will be considered in cases with fused-type OLF compressing spinal cord even though they do not have myelopathic symptoms.  相似文献   
108.

Objective

The purpose of this study was to evaluate the use of diffusion-weighted imaging (DWI) for the detection and characterisation of focal hepatic lesions compared with the use of T2 weighted imaging.

Method

45 patients with 97 hepatic lesions (51 malignant lesions and 46 benign lesions) were included in this retrospective study. Malignant hepatic lesions included 12 hepatocellular carcinomas, 26 metastases and 13 intrahepatic cholangiocarcinomas. Benign hepatic lesions included 19 haemangiomas and 27 cysts. The MRI protocol for the upper abdomen included T2 weighted images, in- and opposed-phase T1 weighted images and dynamic T1 weighted images. Breath-hold fat-suppressed single-shot echo planar DWI was performed with the following parameters: 1338/66; b factors, 0, 50 and 800 s mm–2. Two independent observers reviewed the T2 weighted images and the DWI to detect and to characterise the hepatic lesions.

Results

For detection of malignant hepatic lesions, the use of DWI showed a significantly higher detection rate than the use of T2 weighted images (p<0.05). However, there was no significant difference between the use of DWI and T2 weighted images for benign hepatic lesions. For the differentiation between malignant and benign hepatic lesions, there was no significant difference in sensitivity, specificity and accuracy between the use of T2 weighted images and the use of DWI.

Conclusion

The use of DWI was better for the detection of malignant hepatic lesions than the use of T2 weighted images. However, for detection of benign hepatic lesions and characterisation of hepatic lesions, the use of DWI was equivalent to the use of T2 weighted images.Accurate detection and characterisation of focal hepatic lesions is important for treatment planning in patients with hepatic tumours. For the detection and characterisation of hepatic lesions, CT and MRI are usually employed [1,2]. MRI, T1 weighted, T2 weighted and gadolinium-enhanced T1 weighted imaging have been commonly utilised [3,4].With rapid progress of the use of parallel imaging techniques such as sensitivity encoding (SENSE), the quality of diffusion weighted single-shot echo-planar imaging has improved [5]. Diffusion-weighted MRI of the abdomen has become possible by the use of this technique, which reduces acquisition time, minimises echo-planar imaging artefacts and improves the quality of images [5].Several studies have characterised focal hepatic lesions by measurement of the lesion apparent diffusion coefficient (ADC) [6-11] and have evaluated detection of focal hepatic lesion by use of diffusion-weighted imaging (DWI) [12-16]. However, there is still controversy regarding the value of DWI for the characterisation of focal hepatic lesions as the ADC values of different types of lesions overlap [6-11]. Furthermore, a limited number of studies have been performed using DWI for the detection of hepatic lesions [12-16].The purpose of this study was to evaluate the use of DWI for the detection and characterisation of focal hepatic lesions compared with the use of T2 weighted imaging.  相似文献   
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110.

Background and purpose:

Lipid rafts and caveolae are membrane microdomains with important roles in cell survival signalling involving the Akt pathway. Cholesterol is important for the structure and function of these microdomains. The ginsenoside Rh2 exhibits anti-tumour activity. Because Rh2 is structurally similar to cholesterol, we investigated the possibility that Rh2 exerted its anti-tumour effect by modulating rafts and caveolae.

Experimental approach:

A431 cells (human epidermoid carcinoma cell line) were treated with Rh2 and the effects on cell apoptosis, raft localization and Akt activation measured. We also examined the effects of over-expression of Akt and active-Akt on Rh2-induced cell death.

Key results:

Rh2 induced apoptosis concentration- and time-dependently. Rh2 reduced the levels of rafts and caveolae in the plasma membrane and increased their internalization. Furthermore, Akt activity was decreased and consequently, Akt-dependent phosphorylation of Bad, a pro-survival protein, was decreased whereas the pro-apoptotic proteins, Bim and Bax, were increased upon Rh2 treatment. Unlike microdomain internalization induce by cholesterol depletion, Rh2-mediated internalization of rafts and caveolae was not reversed by cholesterol addition. Also, cholesterol addition did not restore Akt activation or rescue cells from Rh2-induced cell death. Rh2-induced cell death was attenuated in MDA-MB-231 cells over-expressing either wild-type or dominant-active Akt.

Conclusions and implications:

Rh2 induced internalization of rafts and caveolae, leading to Akt inactivation, and ultimately apoptosis. Because elevated levels of membrane rafts and caveolae, and Akt activation have been correlated with cancer development, internalization of these microdomains by Rh2 could potentially be used as an anti-cancer therapy.  相似文献   
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