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11.
Anomalies in prostaglandin (PG) synthesis have been suggested in both experimental and human diabetes mellitus; increased levels of plasma and tissue eicosanoids has been recently reported by several investigators. One step in prostaglandin synthesis is the enzymatic hydrolysis of membrane phospholipids by Phospholipase A2 (PLA2). Nevertheless the alternative pathway involving Phospholipase C must be considered. An evaluation of PLA2 activity is therefore a useful method for studying prostaglandin synthesis in the peripheral target tissues of insulin activity. We studied PLA2 activity in normal and diabetic rat muscle. Streptozotocin-induced diabetic rats showed significantly higher muscular PLA2 activity when compared with controls (3.04 x 10(-2) +/- 0.50 x 10(-2) versus 1.34 x 10(-2) +/- 0.35 x 10(-2) arachidonic acid pMol.mg protein-1.min-1 (p less than 0.01). This effect was not observed in diabetic animals successfully treated with insulin (1.78 x 10(-2) +/- 0.5 x 10(-2) versus 1.34 x 10(-2) +/- 0.35 x 10(-2) arachidonic acid pMol.mg protein-1.min-1), and a significant correlation was found between blood glucose and muscular PLA2 activity (r = 0.42; p less than 0.05). Our results clearly show that in streptozotocin-induced diabetic rats muscular PLA2 activity is significantly higher. The relationship between blood glucose levels and muscular PLA2 activity and the decrease of PLA2 activity after insulin treatment suggest that these changes may be related to a defect in insulin effect.  相似文献   
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Macrophage infiltration is frequent in the early stages of various proliferative eye disorders, including subretinal neovascularization. In this study, we set out to establish the origin of macrophages found in an animal model of laser-induced subretinal neovascularization. One primate received several intravenous injections of a colloidal carbon suspension. We then applied standard argon laser lesions to the retina of both eyes, which were enucleated eight days later and sectioned serially for histological examination. A quantitative estimate of carbon-laden and non-laden leukocytes was made based on morphological criteria. Mononuclear leukocytes accumulated in the laser lesions and the percentage of carbon-laden mononuclear leukocytes in relation to the total leukocyte number was higher in the extravascular area of the laser sites than in the systemic circulation. These findings indicate that the majority of mononuclear leukocytes that accumulate at the sites of laser lesions are derived from the systemic circulation.  相似文献   
13.
Comorbidity of migraine is important from a number of different perspectives. Co-occurrence of different diseases may complicate diagnosis as a high degree of symptomatic overlap may occur among conditions associated with migraine. Furthermore, comorbidity has also important implications for treatment. The commonest comorbidities of migraine are represented by psychiatric disorders, epilepsy, tremor, stroke, and cardiovascular abnormalities.  相似文献   
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Patients who underwent isolated aortic valve replacement could come to attention for new onset aortic disease or progression of borderline alterations not corrected at the first operation, especially in the subset of bicuspid valve disease. We describe our technique in redo operations for aortic root disease, using only a vascular graft and sparing the previously implanted valve prosthesis. In case of normally functioning mechanical prosthesis, we always left the valve in situ and substituted the aortic root with a Dacron conduit, extending the replacement if necessary to the other diseased portions of the thoracic aorta.  相似文献   
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Editorial comment   总被引:1,自引:0,他引:1  
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Composite resin has proven to be a predictable and reliable restorative material for the treatment of traumatized dentin or dental caries in the anterior region. Ongoing material advancements continue to contribute to favorable results in the treatment of the contemporary patient. In using a resin material, it is important for the dental professional to establish an appropriate clinical approach that will protect healthy tissues, while meeting the patient's expectations. This article presents a series of cases that encompass the clinical and aesthetic possibilities provided by modern composites. LEARNING OBJECTIVES: This article depicts the potential clinical and aesthetic results that can be achieved using contemporary composite resins. Upon reading this article, the reader should: 1) Understand operative techniques for obtaining aesthetic results in the anterior maxilla. 2) Become familiar with the importance of formulating a treatment strategy that combines minimum chairtime with a high-quality, aesthetic result.  相似文献   
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AIM: Ameloblastoma is the most frequent epithelial tumor of the jaws. The spread is locally invasive and it tends to recur. Malignant transformation and occurrence of metastases has been described. Immunohistochemical analysis shows an enhanced expression of P53 protein in ameloblastomas. Mutation of the tp53 tumor suppressor gene was verified in several human tumors. In this study histological sections were analyzed for the expression of P53 protein and the tp53 gene was examined for mutations. MATERIAL AND METHODS: Tumor DNA from 29 patients with an ameloblastoma was examined for mutations in exons 5 to 8 of the tp53 tumor suppressor gene using PCR, SSCP,- and sequential analysis. Histological sections of the tumors were analyzed immunohistochemically for an overexpression of P53 protein. RESULTS: Two tp53 mutations (6.9%) in ameloblastomas were verified for the first time. In all 58.6% of the tumors showed an immunoreactivity for P53 protein. There was a statistically significant positive correlation (Fisher's exact test p<0.0148) between an increased number of P53-positive tumor cells and the appearance of recurrence. DISCUSSION: In the face of the uncertain postoperative behavior of ameloblastomas, the immunohistochemical verification of more than 10% P53-positive tumor cells may give a prognostic indication for a tendency to recurrence.  相似文献   
20.
n = 2), port site infection ( n = 2), and subumbilical hematoma ( n = 1). Major morbidity was bile leakage from the cystic duct stump in two cases due to clips or transcystic duct drainage displacement, respectively. One elderly, high risk patient died after being referred for several failed attempts of endoscopic clearance; she died from cardiogenic shock 3 days after successful laparoscopic treatment. Laparoscopic CBD exploration is feasible and safe in most patients, with short-term results that compare favorably with the results of sequential ES/LC reported in the literature.  相似文献   
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