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61.
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P-cadherin expression in breast carcinomas has been associated with tumors of high histologic grade and lacking estrogen receptor-alpha, suggesting a link between these proteins. In the MCF-7/AZ breast cancer cell line, blocking estrogen receptor-alpha signaling with the antiestrogen ICI 182,780 induced an increase of P-cadherin, which coincided with induction of in vitro invasion. Retroviral transduction of MCF-7/AZ cells, as well as HEK 293T cells, showed the proinvasive activity of P-cadherin, which requires the juxtamembrane domain of its cytoplasmic tail. This study establishes a direct link between P-cadherin expression and the lack of estrogen receptor-alpha signaling in breast cancer cells and suggests a role for P-cadherin in invasion, through its interaction with proteins bound to the juxtamembrane domain.  相似文献   
63.
OBJECTIVE: To compare the incidence of diplopia after topical or regional injection anesthesia in cataract surgery. STUDY DESIGN: Retrospective, noncomparative interventional case series. PARTICIPANTS AND METHODS: Three thousand five hundred forty-two consecutive cataract surgeries, performed from March 1998 to December 2001, were studied. MAIN OUTCOME MEASURES: Incidence and mechanisms of diplopia. RESULTS: Two thousand one hundred twenty-two patients were operated under regional and 1420 under topical anesthesia. Twenty-four cases of diplopia were observed, 21 (87.5%) in the regional group and 3 (12.5%) after topical anesthesia (P = 0.005). Eleven cases (45.8%) were secondary to motility problems, all in the regional anesthesia group (P = 0.006). Eight cases (33.3%) were secondary to refractive errors or intraocular lens luxation, 5 after regional and 3 after topical anesthesia (P = 0.88). Five cases (20.8%) were secondary to fusion loss, all in the regional anesthesia group (P = 0.06). CONCLUSIONS: In our study, topical anesthesia was associated with a lower incidence of diplopia relative to regional injection anesthesia. No cases of diplopia secondary to fusion loss or muscle damage were found after topical anesthesia surgery.  相似文献   
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OBJECTIVE: The persistence of cerebral blood flow (CBF) in patients with whole brain death (BD) diagnosis is an unusual phenomenon. We describe patients with whole BD diagnosed despite persistence of intracranial blood flow on transcranial Doppler sonography (TDS). MATERIALS AND METHODS: From January 2001 to December 2002, we reviewed the records of 11 patients. Etiology of BD was craniocephalic trauma in 2 cases, schemic cerebrovascular accident (CVA) in 4 cases, Hemorrhagic CVA in 3 cases, subaracnoid hemorrhage in 1 case, and acute hydrocephalus in 1 case. Six patients had a cerebral decompressive mechanism. In all patients, TDS was used to confirm BD after clinical diagnosis. Additionally, all patients underwent an electroencephalogram (EEG). In 3 patients cerebral angiography (CA) and in 2 others radionuclide angiography (RA) with Tc99m HMPAO were done. RESULTS: All TDS studies showed persistent telediastolic positive flow in at least 1 artery. Because the TDS did not confirm the clinical diagnosis of BD, EEG tests were performed showing silence of bioelectrical activity. Those cases showed CA or RA results with a complete absence of CBF. CONCLUSION: The TDS technique directly evaluates the intracranial but not the intracerebral circulation. For this reason, during the BD diagnosis for patients with previous decompressive techniques, it was possible to find persistence of intracranial telediastolic flow using TDS. In those cases, it is advisable to use other tests to confirm the clinical diagnosis of BD.  相似文献   
66.
OBJECTIVE: Pilocytic astrocytomas (PA) are Grade I brain tumors characterized by an excellent prognosis. In some cases, however, the patient has a bad outcome. The aim of our study was to search for the clinicopathological factors underlying the prognosis for patients with this disease. METHODS: We reviewed the clinical, neuroradiological, and histopathological features of 80 PAs (33 cerebellar, 18 optochiasmatic, 16 brainstem, 7 spinal cord, 3 thalamic, 2 optic nerve, and 1 hemispheric) in pediatric patients. RESULTS: Pathological examination revealed 58 classic PAs and 20 pilomyxoid astrocytomas, which are a histological variant of PAs. Two cases remained unclassified. The mean overall follow-up period was 58 months, the 5-year progression-free survival rate was 75%, and the 5-year survival rates were 100 and 92% after total and partial removal. Univariate statistical analysis revealed that partial resection, optochiasmatic PA localization, and pilomyxoid variant were associated with a worse prognosis, but the latter two parameters were too closely related to the extent of resection to be independent prognostic factors in multivariate analysis. Among the patients who underwent partial surgical removal, only invasion of the surrounding structures was related to prognosis. CONCLUSION: PAs are benign tumors, but some clinicopathological factors, such as partial resection, optochiasmatic location, invasion of surrounding structures, and the pilomyxoid variant, have a worse prognosis.  相似文献   
67.
BACKGROUND AND PURPOSE: Dysembryoplastic neuroepithelial tumors (DNTs) are benign lesions affecting children and are associated with epilepsy. The goal of our study was to better characterize the clinical-radiologic-pathologic spectrum of DNTs (complex and simple forms only) in a series of 14 children. METHODS: Clinical, neuroradiologic, and pathologic features of all cases were retrospectively studied. RESULTS: Eleven cases of complex and three cases of simple DNTs were identified. Mean follow-up was 87 months, and no recurrence was recorded except for one case of simple DNT. We found that some neuroradiologic features may be helpful to support the diagnosis of DNT: presence of "septations," triangular pattern of distribution, and absence of contrast enhancement. CONCLUSION: The evidence of the specific glioneuronal element is found by pathologic examination, but the typical neuroradiologic aspect of DNT suggests this diagnosis preoperatively. Radiologic examination may be helpful for the diagnosis of DNT when pathologic findings are inconclusive.  相似文献   
68.
The role the FAS and BCL-2 in the apoptosis of testicular cells in the contralateral testis after unilateral testicular torsion, was investigated. We compared with control group. These experiments were performed in male Wistar rats prepuberal old. FAS and BCL-2 determination is realized in cells cultures of contralateral testis. Flow cytometry and immunohistochemistry studies, using a FAS and BCL-2 specific monoclonal antibody, were utilized to value FAS y BCL-2 expression on testiculaires cells following unilateral testicular torsion. We observed an increase of expression of FAS and decrease of BCL-2 in the contralateral testis in comparison with control group. The present results may indicate that the expression of this molecules is implicated in cellular apoptosis.  相似文献   
69.
The cellular degeneration, present at the criptorchidism leads to a malfunction in the spermatogenosis and it's due to cellular apoptosis (programed cellular death). This process is turned on and modulated by different ways. One of then is mediated by Ag-Ac reactions and a protein called FAS seems to have an important role in it's modulation. We studied the relation between FAS an the increased apoptosis in undescended testics. Testicular biopsies were done in criptorchid patients during orchidopexy and FAS was measured by immune-techniques. Our results seem to dismiss FAS as a modulation apoptosis factor in the cryptorchidism.  相似文献   
70.
The effect of hesperetin, naringenin and its glycoside form on the Sindbis neurovirulent strain (NSV) replication in vitro was studied. All flavanones tested were not cytotoxic on Baby Hamster cells 21 clone 15 (BHK-21). Antiviral effect was evaluated by a colorimetric assay using MTT (3-(4,5 dimethylthiazol-2-yl)-2,5-dipheyl-tetrazolium bromide) and by plaque reduction assay. Hesperetin and naringenin had inhibitory activity on NSV infection. The 50% inhibitory doses (ID(50%)) of both compounds were 20.5 and 14.9 microg/ml respectively, as established by plaque assay. However their glycosides, hesperidin and naringin did not have inhibitory activity. Implying that the presence of rutinose moiety of flavanones blocks the antiviral effect. Oxygenation on the 3' positions at the B rings on the hesperetin skeleton decrease the anti viral activity at 25 microg/ml.  相似文献   
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