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51.
One new stilbene glucoside (6), along with five known compounds (1-5), were isolated from the roots of Polygonum multiflorum Thumb., and their chemical structures established based on physicochemical and spectroscopic data. Of the compounds, compound 3 showed DNA topoisomerase I and II inhibitory activities.  相似文献   
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Four alkaloids (1-4), three quinolone alkaloids (5-7), and three flavanoid glucosides (8-10) were isolated from the fruits of Evodia officinalis Dode, and their structures were determined from chemical and spectral data. Compounds, 3, 8, 9 and 10 were isolated from this plant for the first time. Of these compounds, 1-3 and 5-7 exhibited moderate cytotoxicities against cultured human colon carcinoma (HT-29), human breast carcinoma (MCF-7), and human hepatoblastoma (HepG-2). Compound 8 showed strong inhibitory effects on DNA topoisomerases I and II (70 and 96% inhibition at a concentration of 20 microM, respectively).  相似文献   
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OBJECTIVES: Claudin proteins represent a large family of integral membrane proteins crucial for tight junction formation and function and they have been shown to be expressed differently in various cancers. We investigated whether the expressions of claudin-1 and claudin-7 are associated with the progression of uterine cervical neoplasia. METHODS: We analyzed 89 formalin-fixed paraffin embedded cervical tissues that included 10 normal cervical epithelium, 19 low-grade squamous intraepithelial lesion (LSIL), 20 high-grade squamous intraepithelial lesion (HSIL), 20 invasive squamous cell carcinoma (ISCC) without lymph node (LN) metastasis, and 20 ISCC with LN metastasis. The expressions of claudin-1 and claudin-7 were determined by immunohistochemistry. RESULTS: The expressions of claudin-1 and claudin-7 were undetectable in normal cervical squamous epithelium, but had variable staining in the basal layer of normal endocervical glands. The expressions of both proteins, mainly as membranous staining, gradually increased in accordance with the progression from LSIL to HSIL and ISCC (both P values are <0.001) and were detected in all cases of ISCC. CONCLUSIONS: These results suggest that claudin-1 and claudin-7 may play a significant role in tumor progression of cervical neoplasia and may represent useful markers for malignant transformation of cervical squamous cells. Further studies would likely result in the development of novel approaches for early detection and therapy for this disease.  相似文献   
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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   
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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   
56.

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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