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Background

Oxidative stress is a crucial factor in the pathophysiology of acute pancreatitis and its systemic complications. Lazaroids are a novel class of antioxidants that potently protect pancreatic acinar cells against oxidant attack. The aim of our study was to evaluate the therapeutic potential of 21-aminosteroid U-74389G in pancreatic injury after ischemia and reperfusion of the organ in a swine model.

Materials and methods

Twelve pigs (weighing 28–35 kg) were randomized into the following two experimental groups: group A (control group, n = 6): ischemia of pancreas (30 min) followed by reperfusion for 120 min; and group B (n = 6): ischemia of pancreas (30 min), U-74389G intravenous injection (10 mg/kg) in the inferior vena cava, and reperfusion for 120 min. Tissue and blood sampling was conducted at 0, 30, 60, 90 and 120 min after reperfusion. Repeated measures analysis of variance was performed for the evaluation of differences between the two groups.

Results

Histopathologic evaluation did not reveal a statistically significant difference concerning hemorrhage (P = 0.193), leukocyte infiltration (P = 0.838), acinar necrosis (P = 0.183), and vacuolization (P = 0.185) in the pancreatic tissue between the two groups; nevertheless, edema seemed to be more pronounced in the U-74389G group (P = 0.020). Serum metabolic data in the control and therapy groups were not significantly different; accordingly, tissue malondialdehyde levels (P = 0.705) and tumor necrosis factor α values (P = 0.863) did not differ between the two groups.

Conclusions

On the basis of the histologic data and the absence of reduction in the malondialdehyde and tumor necrosis factor α levels, it is concluded that the administration of U-74389G does not seem to exert a sizable therapeutic effect in attenuating pancreatic damage from ischemia–reperfusion injury.  相似文献   
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Gardner’s syndrome (GS) is an autosomal dominant form of polyposis characterized by the presence of multiple polyps in the colon together with osseous tumors and soft-tissue tumors, such as epidermoid cysts and lipomas. An osteoma is a benign, osteogenic tumor and may be sporadic or related to GS. Here, we present a patient with a giant sino-orbital osteoma and blepharoptosis as the only symptom of incomplete GS. A 74-year-old woman, with no previous history of trauma or ophthalmic surgery, presented with a 2 years history of right blepharoptosis without diplopia. The results of slit-lamp and fundoscopic examination were normal. Computed tomography showed a giant sino-orbital osteoma. With suspicion for GS, we thoroughly examined the patient and found no soft-tissue tumors. Fifteen years ago, the patient, who had a family history of colonic polyposis, underwent right colectomy and chemotherapy for adenocarcinoma. We report a case of incomplete GS with blepharoptosis as the first symptom.  相似文献   
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Objectives

The significance of vascular endothelial growth factor (VEGF) and inhibitor of differentiation/DNA synthesis (Id-1) in tumor neoangiogenesis and tumor progression in pancreatic ductal adenocarcinoma (PDAC) is still unclear. Given the central role of VEGF in cancer angiogenesis and the inconclusive results on Id-1 expression in PDAC, it is of great interest to investigate whether Id-1 and VEGF expression are associated with angiogenesis and prognosis in PDAC.

Methods

Paraffin-embedded specimens from 60 consecutive patients with PDAC were immunostained for VEGF, Id-1 and CD34 and staining quantification was assessed by Image analysis system. The correlations among the expression of individual angiogenic factors and microvessel density (MVD), clinicopathologic features and clinical prognosis were analyzed.

Results

Id-1 and VEGF Positive Activity Indices (PAIs) closely correlated with each other. MVD positively correlated with both Id-1 and VEGF expression. More advanced T and N status correlated with more intense expression of Id-1, VEGF and higher MVD. With regard to prognostic significance higher Id-1 PAI (adjusted HR = 1.69, 95%CI: 1.10–2.59, p = 0.017), higher VEGF PAI (adjusted HR = 2.66, 95%CI: 1.09–6.50, p = 0.032), and MVD (adjusted HR = 1.55, 95%CI: 1.27–1.88, p < 0.001) were associated with poorer survival.

Conclusions

VEGF and Id-1 overexpression were found to be associated with high MVD and emerged as adverse prognostic factors in terms of patient survival in PDAC. The potential of selective anti-angiogenic targeting therapy for pancreatic malignancies should prompt further validation of the present findings in studies encompassing larger samples and more elaborate techniques.  相似文献   
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Estep  TN; Pedersen  RA; Miller  TJ; Stupar  KR 《Blood》1984,64(6):1270-1276
Di-(2-ethylhexyl) phthalate (DEHP) accumulates in blood brought into contact with materials utilizing this compound as a plasticizer. To determine whether this phthalate diester affects red blood cell integrity, we have compared cell morphology, plasma hemoglobin accumulation, micro-vesicle production, and the concentration of intracellular metabolites and electrolytes of erythrocytes from blood stored at 4 degrees C with and without DEHP. When sufficient emulsified DEHP was mixed with blood to give a final concentration of 300 micrograms/mL, plasma hemoglobin accumulation was reduced by an average of 70%, the percentage of cells exhibiting normal morphology was enhanced by at least 20-fold, and the volume of microvesicles released from red blood cells was reduced by 50% after 35 days of refrigerated storage compared to the values obtained from corresponding samples stored without added phthalate. Similar effects were observed regardless of whether blood was stored in nonplasticized polypropylene or tri-(2-ethylhexyl) trimellitate plasticized polyvinylchloride containers and with DEHP solubilized by a variety of emulsifiers. When 300 micrograms/mL DEHP was added to stored blood containing erythrocytes predominantly in the echinocyte conformation, many of the cells reverted to the normal discoid morphology. The addition of this quantity of DEHP to blood had no significant effect on the course of storage-induced changes in erythrocyte adenosine triphosphate (ATP), 2,3-diphosphoglycerate (2,3-DPG), sodium or potassium concentrations. The data are consistent with the hypothesis that DEHP inhibits the deterioration of the red blood cell membrane that results from the refrigerated storage of whole blood.  相似文献   
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