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1.
AimLung metastases are a negative prognostic factor in Ewing sarcoma, however, the incidence and significance of sub-centimetre pulmonary nodules at diagnosis is unclear. The aims of this study were to (1): determine the incidence of indeterminate pulmonary nodules (IPNs) in patients diagnosed with Ewing sarcoma (2); establish the impact of IPNs on overall and metastasis-free survival and (3) identify patient, oncological and radiological factors that correlate with poorer prognosis in patients that present with IPNs on their staging chest CT.Materials & methodsBetween 2008 and 2016, 173 patients with a first presentation of Ewing sarcoma of bone were retrospectively identified from an institutional database. Staging and follow-up chest CTs for all patients with IPN were reviewed by a senior radiologist. Clinical and radiologic course were examined to determine overall- and metastasis-free survival for IPN patients and to identify demographic, oncological or nodule-specific features that predict which IPN represent true lung metastases.ResultsFollowing radiologic re-review, IPN were found in 8.7% of patients. Overall survival for IPN patients was comparable to those with a normal staging chest CT (2-year overall survival of 73.3% [95% CI 43.6–89] and 89.4% [95% CI 81.6–94], respectively; p = 0.34) and was significantly better than for patients with clear metastases (46.0% [95% CI 31.9–59]; p < 0.0001). Similarly, there was no difference in metastasis-free survival between ‘No Metastases’ and ‘IPN’ patients (p = 0.16). Lung metastases developed in 40% of IPN patients at a median 9.6 months. Reduction of nodule size on neoadjuvant chemotherapy was associated with worse overall survival in IPN patients (p = 0.0084).ConclusionIPN are not uncommon in patients diagnosed with Ewing sarcoma. In this study, we were unable to detect a difference in overall- or metastasis-free survival between patients with IPN at diagnosis and patients with normal staging chest CTs.  相似文献   
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Ewing sarcoma (ES) is a rare primary neoplasm in the lumbar adult spine and may mimic a benign tumor. In this case, after a patient's three-month history of lower back pain and rapidly progressing leg numbness and weakness, magnetic resonance imaging (MRI) showed a mass in the third lumbar vertebra. At a two-month follow-up, imaging showed a fracture, compression and lesion enlargement. Decompression and fixation confirmed ES, and the patient began combined radiotherapy and chemotherapy. Two months postoperatively, residual ES was suspected on MRI. The patient underwent a second surgery, and histopathology confirmed necrosis. A six-month follow-up after the first surgery showed no tumor recurrence. This case supports the inclusion of ES in the differential diagnosis of pathologic spinal fracture. Early decompression and spinal fixation are critical for preserving neurologic and spinal functions in ES complicated by a compression fracture. Combined adjuvant radiotherapy and chemotherapy remain the standard therapeutic strategy.  相似文献   
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 目的 研究Ewing’s肉瘤细胞系 (RM 82 )X 射线外照射后肿瘤坏死因子 (TNF α)和转化生长因子 (TGF β)mRNA表达水平的变化 ,探讨X 射线诱导内源性TNF α和TGF β产生的可能性及意义。 方法 应用实时荧光RT PCR ,检测接受不同剂量X 线照射 (2Gy ,5Gy ,10Gy ,2 0Gy ,30Gy ,4 0Gy)和受照后不同时间 (1h ,3h ,6h ,12h ,2 4h ,4 8h ,72h)。TNF α和TGF βmRNA表达水平的变化。 结果 RM 82细胞TNF αmRNA表达水平较外照射前显著升高。一方面受照后TNF αmRNA表达逐渐升高 ,照射剂量达 4 0Gy时TNF αmRNA表达水平达高峰 ,为正常对照组的 10 8倍 ;另一方面 ,照射后 3h后TNF αmRNA表达逐渐升高 ,6h达高峰 ,为正常对照组的 18倍。相反 ,TGF βmRNA表达水平X 射线照射前后无显著变化。结论 Ewing’s肉瘤细胞系 (RM 82 )接受X 线照射后TNF αmRNA表达明显升高 ,且呈现时间、剂量依赖性。放射治疗可诱导Ewing’s肉瘤细胞系 (RM 82...  相似文献   
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The field of molecular genetics continues to see an ever increasing number of applications to pediatric tumor analysis. Studies in pediatric tumors have identified novel genes and other genetic changes, a large number of which reflect one of the following mechanisms: (1) activation of proto-oncogenes; (2) loss of tumor suppressor genes; or (3) creation of novel fusion proteins. At least one of these mechanisms is operational in each of the following pediatric tumors: neuroblastoma, Ewing sarcoma and peripheral primitive neuroectodermal tumor (pPNET), intra-abdominal desmoplastic small-cell tumor, rhabdomyosarcoma, synovial sarcoma, and Wilms tumor. Out of this research has come not only an increased understanding of oncogenesis but also, for each of the tumors listed above, diagnostic and/or prognostic markers that can be used by the pathologist and oncologist to improve overall patient management. Received November 20, 1997; accepted April 20, 1998.  相似文献   
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Background: In the multicenter European Intergroup Cooperative Ewing's Sarcoma Studies, localized Ewing tumors of bone were treated by combination chemotherapy with surgery and/or radiotherapy. Patients with primary metastases (pm-pts) were treated in high risk protocols.Patients and methods: One hundred seventy-seven pm-pts were registered from January 1990 to December 1995, 171 were evaluable for survival analyses. Thirty-six pm-pts received myeloablative megatherapy with stem cell rescue following conventional treatment. Bilateral whole lung irradiation (WLI) was administered in 57 pm-pts with pulmonary involvement. Event-free survival (EFS) rates were estimated by Kaplan–Meier analysis. Prognostic factors were identified by log-rank statistics, Cox procedures and logistic regression.Results: Eighty-nine deaths were recorded by 1 February 1997, EFS four years after diagnosis for all 171 pm-pts was 0.27. EFS for isolated lung metastases was 0.34, for bone/bone marrow (BM) metastases, 0.28, and for combined lung plus bone/BM metastases, 0.14 (P < 0.005). WLI improved outcome in case of isolated pulmonary involvement (0.40 vs. 0.19, P < 0.05). In pm-pts with combined pulmonary/skeletal metastases, intensification by megatherapy and/or WLI improved EFS from 0.00 to 0.27 (P = 0.0001).Conclusions: EFS four years after diagnosis in patients with disseminated Ewing tumors is 0.27. Whole lung irradiation and megatherapy improve outcome in subgroups of patients with disseminated Ewing disease.  相似文献   
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Objective.To describe the clinical, radiological and MRI features of six atypical cases of histologically proven appendicular Ewing sarcoma/ primitive neuroectodermal tumour (PNET). Design. Retrospective review of case notes and available imaging was carried out. Patients. Six patients (4 male, 2 female; mean age 27years, range 19–44 years), presenting over a 77-month period, were identified from the Bone Tumour Register. All had unusual clinical and imaging features for Ewing sarcoma/PNET. Results and conclusions. Four tumours were centred on the distal femoral metaphysis, one in the proximal tibial metaphysis and one in the distal tibial metaphysis. Plain radiographs were available in four cases and showed minor cortical changes. MRI demonstrated a relatively small, eccentrically located intraosseous component with a large, eccentric extraosseous component. Extension into the epiphysis was seen in three cases and into the adjacent joint in two cases. Intraosseous ”skip” metastases were present in three cases. The clinical and imaging features were atypical for conventional intraosseous Ewing sarcoma/PNET and the exact site of origin (intraosseous, periosteal or soft-tissue) was unclear. Received: 6 December 1999 Revision requested: 7 February 2000 Revision received: 20 July 2000 Accepted: 4 August 2000  相似文献   
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目的:探讨三氧化二砷(Arsenic trioxide,As2O3)诱导尤文肉瘤细胞凋亡及对融合蛋白EWS—FLi1表达的影响,.方法:应用噻唑蓝(MTF)法、形态学观察、原位末端标记法(TUNEL)、流式细胞术(FCM)观察As2O3对体外生长的尤文肉瘤RD—ES细胞系生物行为的影响:应用半定量RT—PCR测定应用As2O3前后c—mye基因mRNA水平的变化;应用免疫细胞化学及固定化蛋白印迹法(Western blot)观察用药前后EWS—FLi1融合蛋白表达水平的变化、结果:As2O3对体外生长的RD—ES细胞系具有明显抑制作用,并可诱导细胞凋亡、c-mye基因mRNA表达水平和EWS—FLil融合蛋白表达量随As2O3作用时间延长逐渐降低结论:常规治疗浓度的As2O3对体外生长的尤文肉瘤细胞具有明显的杀伤作用,其作用机制与改变线粒体膜通透性和抑制EWS—Flil融合蛋白、降低c一myc基因表达有关。  相似文献   
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Recent studies in mouse models of cancer have shown that exercise improves tumor vascular function, thereby improving chemotherapy delivery and efficacy. However, the mechanisms underlying this improvement remain unclear and the effect of exercise on Ewing sarcoma (ES), a pediatric bone and soft tissue cancer, is unknown. The effect of exercise on tumor vascular hyperpermeability, which inversely correlates with drug delivery to the tumor, has also not been evaluated. We hypothesized that exercise improves chemotherapy efficacy by enhancing its delivery through improving tumor vascular permeability. We treated ES‐bearing mice with doxorubicin with or without moderate treadmill exercise. Exercise did not significantly alter ES tumor vessel morphology. However, compared to control mice, tumors of exercised mice had significantly reduced hyperpermeability, significantly decreased hypoxia, and higher doxorubicin penetration. Compared to doxorubicin alone, doxorubicin plus exercise inhibited tumor growth more efficiently. We evaluated endothelial cell sphingosine‐1‐phosphate receptors 1 and 2 (S1PR1 and S1PR2) as potential mediators of the improved vascular permeability and increased function afforded by exercise. Relative to tumors from control mice, vessels in tumors from exercised mice had increased S1PR1 and decreased S1PR2 expression. Our results support a model in which exercise remodels ES vasculature to reduce vessel hyperpermeability, potentially via modulation of S1PR1 and S1PR2, thereby improving doxorubicin delivery and inhibiting tumor growth more than doxorubicin alone does. Our data suggest moderate aerobic exercise should be tested in clinical trials as a potentially useful adjuvant to standard chemotherapy for patients with ES.  相似文献   
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