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91.
· Background: The aim of this study was to evaluate the focal electroretinogram (FERG), an objective indicator of outer retinal function, in nonexudative age-related macular degeneration (NE-AMD), and to compare FERG results with morphological lesions assessed by stereoscopic fundus photographs and fluorescein angiograms. · Methods: Twenty-five patients (25 eyes) with bilateral NE-AMD (visual acuity of the study eyes ≥0.4) as well as 10 age- and sex-matched control subjects (10 eyes) were evaluated. FERGs were recorded from the macular region (9°) in response to sinusoidal stimuli flickered at 32 Hz. Amplitude and phase angle of the Fourier-analyzed FERG fundamental component were measured. Fundus lesions were graded from color slides according to the Wisconsin age-related maculopathy grading system [15]. Fluorescein angiograms were evaluated by an image analysis technique to compute the area with pathological hyperfluorescence (associated with drusen and/or retinal pigment epithelial atrophy) within the macular (approximately 9°×9°) region. · Results: Compared to control eyes, NE-AMD eyes had a reduction in the mean FERG amplitude (57% loss, P<0.001) with no phase changes. Amplitudes of individual affected eyes were negatively correlated with either the Wisconsin grading score (r=–0.63, P<0.001) or the percentage area of pathological hyperfluorescence (r=–0.70, P<0.01). Eyes with minimal NE-AMD lesions (Wisconsin score ≤6) and normal acuity had a lower mean amplitude (47% loss, P<0.05) than that of control eyes. · Conclusions: The results indicate that, in NE-AMD, the FERG is altered in parallel with the extent and severity of fundus lesions. However, a functional impairment of outer macular layers, which is detected by FERG losses, could precede morphological changes typical of more advanced disease. Received: 6 March 1998 Revised version received: 5 June 1998 Accepted: 17 June 1998  相似文献   
92.
PURPOSE: Loss of a certain amount of cutaneous tissue of the perineal region may be remedied by first intention with creation of cutaneous flaps, thus preventing second intention healing. METHODS: We present three emblematic cases in which the posterior perineal region was reconstructed by means of vertical subcutaneous pedicle flaps, subsequent to cutaneous tissue loss after surgery for extensive condilomas or neoplastic pathologies. RESULTS: Tissue loss was repaired by means of a V-Y type vertical subcutaneous pedicle flap, constructed laterally of the extirpation zone and advanced in a median direction. In all cases, no ischemia or infection of flaps occurred; sphincteral continence and long-term aesthetic results have proved to be satisfactory. CONCLUSIONS: Vertical pedicle subcutaneous flaps are well vascularized, extremely mobile, and easy to perform and have no serious postoperative complications.  相似文献   
93.
Multiple sclerosis (MS) is a T-cell-mediated autoimmune demyelinating disease of the central nervous system (CNS), associated with an altered immunoregulation. Interferon (IFN)-, also known as immune IFN, is a cytokine with several effects on the immune system. Specific IFN- receptors have been found on human lymphocytes, as well as on other cell types (e.g. gliocytes), even in the CNS. The aim of the present study was to evaluate IFN- binding on peripheral blood T-lymphocytes from MS patients, compared with those from healthy subjects. Thirty-two patients were selected according to the classical criteria for definite MS; as controls, 21 healthy subjects were studied. We have found that T-lymphocytes from MS patients bear a significantly smaller amount of IFN- receptors than those from controls [B max: 568, 18 vs 708, 14 (mean, SE) receptors/cell]. Such IFN- binding sites are of the same type in patients and healthy subjects [K d: 1.0, 0.05 vs 0.9, 0.02 (mean, SE) nM]. These findings are discussed in terms of immunopathogenesis of MS, since it has been reported that activated T-lymphocytes have decreased amounts of IFN- receptors.  相似文献   
94.
In our Institute we have performed 124 vertical banded gastroplasties. Patients with a follow-up beyond 3 months were studied with a barium meal, in order to evaluate the efficiency of surgery and the eventual complications. Seventy-nine patients have had one or more X-ray investigations at various times after surgery (for a total of 136 studies). The first 20 patients were routinely studied at 1, 2 and 3 years after the operation; the next 32 patients were studied for features such as vomiting, poor weight loss or low food intake; the last 27 patients were studied with an early overlook beginning 3 months after surgery. We noted gastroesophageal reflux in eight (10.1%) cases, outlet dilatation in four (5%) cases, outlet substenosis (diameter 6-8 mm) in 13 (16.4%) cases, outlet stenosis (diameter ≤5 mm) in four (5%) cases, peanut-type deformation in three (3.7%) cases, and staple-line disruption in 17 (21.5%) cases. The staple-line disruption was correlated in the first part of the series with a reinforcement of such a suture, while the last 27 patients, with vertical stapling carried out with a 4-row stapler without reinforcement, did not present any disruption. The radiographic examination gives information about weight loss and side effects.  相似文献   
95.
INTRODUCTION: Knowledge accumulation is overfilling the thematic content of medical graduation. Medical Schools must be alert to define a minimal content related with the most frequent disturbs. We intent to suggest topics for the minimal content, to the program of Neurology in medical graduation. METHOD: 1. To identify the places where young doctors are working outside the School Hospital (SH): we analysed the answers of the letters sent to 6415 resident - doctors (RD) in S?o Paulo's State and we made personal interview with 201 RD. 2. To verify the most frequent neuropsychiatric disturbs (ND) in the population: we made the analysis of the patient's diagnostic records in emergency room of three institutions: Municipal of Taubaté-SP, Municipal of S?o José dos Campos-SP and Faculty of Medicine of S?o Paulo Santa Casa de Misericórdia. RESULTS: 1. The RD are young and, outside the SH, they work in other emergency services. 2. The most frequent diagnosis in institutions were listed: alcoholism, cerebrovascular disease, coma, cranial trauma, dementia, dizziness, epilepsy, facial paralysis, faint, headache, hemiplegia or paraplegia, meningitis, others paralysis, periferical neuropathy and psychiatric disorders. CONCLUSIONS: Those diagnostics most frequent are relevant topics of the programmatic content to the program of Neurology in medical graduation.  相似文献   
96.
During the last 20 years, various conservative surgical techniques have been proposed to treat larynx cancer. On the basis of our various experiences and of the ultrastructural data on the tissues treated with radiowaves, we decided to also use radiosurgery in operations under direct microlaryngoscopy. We select 18 patients suffering from epidermoid carcinoma. These patients had been referred to our ENT clinic at the Polichnico of Palermo between 1999 and 2001. The authors describe the surgical procedures used and emphasize the advantages of radiosurgery in the treatment of larynx cancer.  相似文献   
97.
Nimesulide release from micronized and unmicronized drug particles was tested at pH 7.4 by measuring the transfer to dimyristoylphosphatidylcholine liposomes (multilamellar and unilamellar vesicles), chosen as a biomembrane model. The perturbing effect of increasing molar fractions of pure nimesulide on the thermotropic behaviour of dimyristoylphosphatidylcholine liposomes was investigated by differential scanning calorimetry. In order to study the drug dissolution process by its uptake into void liposomes, measurements were carried out on suspensions of blank liposomes added to weighed amounts of free powdered nimesulide (micronized and unmicronized). The amount of drug transferred was quantified by comparing the effect caused by the dissolved and released drug to that caused by the free drug that had been previously molecularly dissolved in the liposomes. The calorimetric results show that the dissolution rate depends on the nimesulide form (micronized or unmicronized), and that the transfer to the void liposomes is quicker when the drug is in a micronized form. The uptake was faster when unilamellar vesicles were used instead of multilamellar vesicles because of the greater lipid surface. The calorimetric technique could represent an alternative 'in vitro' method that can be applied to the study of the dissolution kinetics directly at the site of drug uptake, mimicking a biological system.  相似文献   
98.
PURPOSE: Recently, we reported that a large number of human hepatocellular cancer (HCC) cell lines were auxotrophic for arginine. Here we report the results obtained with the amino acid-degrading enzyme arginine deiminase (ADI) conjugated to polyethylene glycol (ADI-SS PEG 20,000 mw) as a means of lowering plasma arginine to treat HCC. The study was a cohort dose-escalation phase I/II study. PATIENTS AND METHODS: Pharmacodynamic studies indicated an ADI-SS PEG 20,000 mw dose level of 160 U/m(2) was sufficient to lower plasma arginine from a resting level of approximately 130 micromol/L to below the level of detection (< 2 micromol/L) for more than 7 days, a dose later defined as the optimal biologic dose. All patients were to receive three cycles at the optimum biologic dose. RESULTS: This therapy was well tolerated, even in patients who had no detectable plasma arginine for 3 continuous months of therapy. Of the 19 patients enrolled, two had a complete response, seven had a partial response, seven had stable disease, and three had progressive disease. The median survival for the 19 patients enrolled on this study was 410 days, with four patients still alive at present (> 680 days). CONCLUSION: Elimination of all detectable plasma arginine in patients with HCC was well tolerated and seemed to be effective in the treatment of some patients with HCC. Further testing of ADI-SS PEG 20,000 mw in a larger population of individuals with HCC as well as other human tumors auxotrophic for arginine is warranted.  相似文献   
99.
Prognostic value of CD40 in adult soft tissue sarcomas.   总被引:4,自引:0,他引:4  
PURPOSE: The purpose is to evaluate the expression of CD40, a membrane protein predominantly expressed on B cells, dendritic cells, and macrophages, in a series of adult soft tissue sarcomas and to test its possible prognostic value. EXPERIMENTAL DESIGN: CD40 expression was studied by immunohistochemistry. Correlations with other baseline characteristics of patients and tumors were analyzed with chi(2) test. The prognostic value was studied with univariable and multivariable analysis adjusted by age, sex, tumor size, grade, location, and distant metastases. RESULTS: Eighty-two patients, between January 1994 and May 2001, were analyzed. Membrane or cytoplasmic staining for CD40 protein was absent in 30% of the tumors but present in <10% of cells in 22 (27%), in 10% to 50% in 23 (28%), and in >50% of cells in 12 (15%) tumors. There was no correlation between CD40 expression and age, sex, size, grade, and location of the primary tumor and distant metastases. With 61 patients (74.4%) progressed and 31 (37.8%) dead, CD40 expression was a significant prognostic factor for disease-free and overall survival at univariable and multivariable analysis. Patients with tumors expressing CD40 in >50% of cells had a dramatically unfavorable prognosis with median disease-free and overall survival of 7 and 17 months, respectively, and hazard ratios of relapse and death as compared with patients with CD40-negative tumors of 2.89 (95% confidence interval: 1.26-6.60) and 6.92 (95% confidence interval: 2.18-22.0), respectively. CONCLUSIONS: These data suggest that expression of CD40 protein in >50% of cells might indicate an unfavorable prognosis in adult soft tissue sarcomas.  相似文献   
100.
PURPOSE: Stroma cells play a relevant role in tumor development and progression. We investigated the activity of herceptin (HER), a humanized monoclonal antibody widely used for the treatment of HER2-overexpressing epithelial cancer, toward stroma cell lines L87/4 and L88/5. EXPERIMENTAL DESIGN: We studied the antiproliferative potential of HER and role of human serum in HER activity. We also investigated the ability of HER to alter ancillary functions of L87/4 and L88/5, such as support to long-term hematopoiesis, growth factor production, breast cancer cell adhesion, and proliferation. RESULTS: Flow cytometry showed that HER2 membrane expression in L87/4 and L88/5 stroma cells was intermediate between the expression in HER2-negative/dim MCF-7 breast cancer cells and HER2-bright SK-BC3 breast cancer cells. HER2 gene amplification was not detected by fluorescence in situ hybridization in either stromal cell lines. HER significantly inhibited L87/4 and L88/5 proliferation. Mean ID(50)s were found to be 2000 and 1700 micro g/ml for L87/4 and L88/5, respectively, after 3-day exposure and 800 micro g/ml for both cell lines after 9-day exposure. The presence of 10% human serum in the culture increased HER inhibitory activity. IC(50) of stroma cells was found to be intermediate between HER2-bright breast cancer cells (SK-BC3) and HER2-negative/dim breast cancer cells (MCF-7). The drug did not significantly affect the ability of stroma cells to support long-term hematopoiesis in the cobblestone area forming cell assay. In contrast, in coculture assay, MCF7 cells demonstrated a worse adhesion and growth capability on HER-treated stroma layers when compared with untreated stroma. Moreover, HER significantly reduced vascular endothelial growth factor production by L88/5 cells. CONCLUSIONS: Our data support the novel finding that HER may have a relevant activity against stroma cells.  相似文献   
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