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21.
Malignant haemangiopericytoma of the knee joint: MR findings   总被引:2,自引:0,他引:2  
The imaging findings of intra-articular haemangiopericytomas have not been described previously. We report on a 35-year-old man with a primary malignant haemangiopericytoma of the left knee joint. MRI demonstrated joint effusion and a heterogeneous mass with haemorrhagic components and multiple peripheral serpentine signal voids, suggesting the presence of vascular channels. Multiple pulmonary metastases were seen on chest CT. These imaging findings, although not pathognomonic, might be useful in suggesting the diagnosis of intra-articular haemangiopericytoma.  相似文献   
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BACKGROUND: Hypoxia-inducible factor 1alpha (HIF-1alpha) and HIF-2alpha are essential regulatory proteins for the adaptation of tumor cells to hypoxia, and they stimulate angiogenesis through activation of the vascular endothelial growth factor (VEGF) gene. METHODS: HIF-1alpha and HIF-2alpha proteins were studied immunohistochemically in a group of 81 patients with Stage I endometrial adenocarcinoma of the endometrioid cell type. The results were correlated with intratumoral angiogenesis, the expression of the angiogenic factors VEGF and thymidine phosphorylase (TP), and the VEGF/receptor (VEGF/KDR) complex. Relations also were sought with estrogen receptor (ER) and progesterone receptor (PR), with the apoptosis-related proteins bcl-2 and p53, with several histopathologic parameters, and with patient prognosis. In addition, a sample of 25 normal endometria at various phases of the menstrual cycle was studied for the presence of HIF-1alpha and HIF-2alpha. RESULTS: HIF-1alpha expression was detected in 49% of endometrial carcinomas. The expression was cytoplasmic or mixed nuclear/cytoplasmic. HIF-1alpha expression was associated with up-regulation of the VEGF pathway and with increased standard microvessel density (sMVD) and activated VEGF/KDR microvessel density (aMVD). It also was associated with a poor prognosis in both univariate and multivariate analyses. HIF-2alpha protein showed a pattern of expression similar to the pattern seen in HIF-1alpha, but expression of HIF-2alpha protein occurred in only 17% of endometrial carcinomas, and it was associated with increased TP reactivity. There also was a relation of HIF-1alpha expression with well-differentiated endometrial neoplasms, and there was a marginal association of HIF-1alpha and HIF-2alpha with ER expression. With reference to normally cycling tissues, HIF-1alpha nuclear/cytoplasmic expression was particularly strong in the samples of early proliferative phase endometrium compared with HIF-2alpha protein expression, which showed a constant reaction throughout the menstrual cycle. CONCLUSIONS: The up-regulation of HIF-1alpha and, to a lesser extent, of HIF-2alpha is a common event in Stage I endometrial adenocarcinomas. In these tumors, HIF-1alpha expression is related to increased angiogenesis, through activation of the VEGF angiogenic pathway, and to an unfavorable prognosis. HIF-2alpha accumulation is associated with increased expression of the angiogenic factor TP.  相似文献   
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Vascular endothelial growth factor (VEGF) is an important angiogenic factor, linked to poor outcome in human malignancies including non-small cell lung carcinoma (NSCLC). We used the 11B5 monoclonal antibody recognizing the VEGF/KDR complex (R. A. Brekken et al., Cancer Res., 58: 1952-1959, 1998) to assess the VEGF expression in cancer cells and the VEGF/KDR activated microvessel density (aMVD) in early operable NSCLC. The JC70 anti-CD31 monoclonal antibody was used to assess the standard MVD (sMVD). The aMVD was significantly higher in the invading front of the tumors and in the normal lung adjacent to the tumors as compared with normal lung distant to the tumor or to inner tumor areas (P < 0.0002). The sMVD was higher in the normal lung and decreased from the invading front to inner tumor areas (P < 0.0001). However, the vascular activation (aMVD:sMVD) was 4-6 times higher in the tumor areas as compared with lung from normal individuals (36-58% versus 9%; P < 0.0001). Fibroblast 11B5 reactivity, noted in 25% of cases, correlated with high aMVD and sMVD in the inner tumor areas. Multivariate analysis showed that aMVD was the most potent and independent prognostic factor (P = 0.001; t-ratio, 3.28). It is concluded that intense VEGF/KDR angiogenic pathway activation is a tumor-specific feature in more than 50% of NSCLC cases and is associated with poor postoperative outcome. Clinical trials involving targeting of the VEGF/KDR-positive vasculature with specific antibodies, such as 11B5, are, therefore, encouraged.  相似文献   
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The assessment of the angiogenic profile of tumors may become an important tool as a guide for the inclusion of novel drugs and molecular therapies into the standard chemoradiotherapy policy. Several studies have shown the prognostic importance of microvessel density (MVD) and of angiogenic factor expression in operable gastric cancer. In the present study we investigated, with immunohistochemistry the MVD, the expression of vascular endothelial growth factor (VEGF) and of thymidine phosphorylase (TP) expression, as well as the nuclear expression of p53 protein, in a series of patients with locally advanced inoperable gastric cancer. A strong association of VEGF with TP expression was noted (P = 0.005), and tumors coexpressing these factors had a statistically higher MVD (P = 0.0001). Nuclear p53 accumulation was also related to a high MVD (P = 0.004), and this was independent of VEGF or TP expression. Microvessel density showed a bell-shaped association with prognosis; cases with an intermediate MVD exhibit a favorable outcome (P < 0.05). A trend of nuclear TP expression to define a group of patients with poorer prognosis was noted (P = 0.06), while none of the remaining variables showed any significant association. The immunostaining results allowed the grouping of the angiogenic profile in four major categories: 1) highly vascularized tumors with VEGF and/or TP expression (about 36% of cases); 2) highly angiogenic tumors with p53 nuclear accumulation and low VEGF/TP expression (7% of cases); 3) poorly vascularized tumor with low VEGF/TP and negative nuclear p53 staining (32% of cases); 4) poorly vascularized tumors with TP expression (7% of cases). Specific therapies targeting hypoxia, VEGF, or TP expression as well as p53 gene therapy have entered clinical experimentation or are already available for clinical use. Using the suggested markers more than 80% of locally advanced gastric carcinomas can be grouped in different categories according to their angiogenic profile. Such a categorization may be useful for phase III trials on novel therapies targeting the major angiogenesis-related features studied here.  相似文献   
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BACKGROUND: We evaluated the value of coronary artery calcification (CAC) score in coronary artery disease (CAD) detection in asymptomatic hemodialysis (HD) patients by evaluating the association among CAC score, exercise electrocardiography (EECG), and Thallium-201 dipyridamole scintigraphy. Correlation between aortic pulse wave velocity (PWV) and CAC score was also evaluated. METHODS: CAC score was assessed with conventional computed tomography in 40 patients. Thirty patients completed EECG and 25; those with a positive CAC score and/or a positive EECG performed Thallium dipyridamole scintigraphy. Carotid-femoral PWV was assessed in all patients. RESULTS: There was no association among CAC score and EECG or Thallium dipyridamole scintigraphy. In contrast, CAC score was correlated with aortic PWV. CONCLUSION: The previous results question the role of CAC score in the detection of CAD in asymptomatic HD patients. The correlation between CAC score and aortic PWV raises the possibility that CAC score represents more an indicator of coronary artery medial wall calcification than a marker of CAD.  相似文献   
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The assessment of tumor molecular features in combination with the detection of occult malignant cells may provide important clinical information, beyond the standard staging of breast cancer. Using a nested RT-PCR technique, we assessed prospectively the presence of cytokeratin-19 (CK19) mRNA positive cells in the blood of 100 operated patients with breast cancer before the initiation of adjuvant chemotherapy and local radiotherapy. Tissue samples were prospectively collected and analyzed for estrogen (ER) and progesterone (PgR) receptor, c-erbB-2 overexpression, mutant-p53 and bcl-2 protein accumulation, proliferation index and microvessel density (MVD). CK-19 mRNA-positive cells were detected in the peripheral blood of 33% of patients. Simultaneous display of high intratumoral MVD and of CK-19 mRNA-positive cells, which characterized highly angiogenic and disseminated in the peripheral blood (HAD) disease was noted in 25% of patients. Detection of CK-19 positive cells was significantly associated with increased MVD (p = 0.002). In univariate analysis (median follow-up 30 months) CK19 mRNA detection and MVD were the most significant factors related to a short relapse-free survival (RFS), (p < 0.0001). In multivariate analysis, CK19 positivity, high MVD and c-erbB-2 overexpression were the only significant and independent variables associated with relapse (p = 0.0005, 0.03 and 0.04, respectively). Patients with HAD had an expected relapse rate close to 70% vs. <5% in the remaining patients irrespectively of the used chemotherapy regimen. The simultaneous presence of high MVD and CK19-positive cells in the blood of patients with early breast is linked with poor prognosis, which cannot be improved with standard chemotherapy regimens.  相似文献   
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