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41.
Our previous study of natural autoantibodies showed that anti-lymphocyte antibodies are frequently produced by perinatal B cells from normal strains of mice. One-third of these monoclonal antibodies (mAb) recognized similar epitopes on the surface of thymocytes. In the present report, we have characterized the molecule recognized by three of these mAb (D10, G7, 22). These mAb identified a 100-kDa protein (p100) on the surface of thymocytes. This protein resolved into 70-kDa polypeptide chains under reducing conditions. Inhibition experiments as well as antibody immunoprecipitations in the presence of mild detergents revealed non-covalent association of the p100 with Thy-1 and ThB. A similar multimolecular complex was identified following chemical cross-linking of thymocyte surface proteins. Analysis of several Thy-1-defective mutant cells lines, and thymocytes treated with phosphatidylinositol-specific phospholipase C (PI-PLC) showed that the expression of p100 was strongly influenced by Thy-1 molecule. The p100 was resistant to PI-PLC treatment and was not released into the supernatant as was the case for Thy-1 and ThB molecules. These data lead us to propose that the p100 is a transmembrane protein, the expression of which in the plasma membrane is dependent on the association or presence of Thy-1 molecule. 相似文献
42.
F. Calais da Silva 《Infection》1992,20(Z3):S221-S223
The aim of prophylactic antibiotic therapy in urological surgery is the prevention of local or systemic infections. The authors treated 100 patients prophylactically; 62 were treated with amikacin and 38 with cefotaxime. Of the 62 patients treated with amikacin, 18 had infectious complications. Of the 38 patients treated with cefotaxime, ten had infectious complications. We conclude that in the Hospital do Desterro the incidence of infectious complications is high, despite antibiotic prophylaxis.Das Ziel der Antibiotikaprophylaxe bei urologischen Operationen ist die Verhinderung von lokalen und systemischen Infektionen. Die Autoren führten bei 100 Patienten eine Prophylaxe durch; 62 Patienten wurden mit Amikacin und 38 Patienten mit Cefotaxim behandelt. Von den 62 mit Amikacin behandelten Patienten hatten 18 und von den 38 mit Cefotaxim behandelten Patienten hatten zehn Patienten infektiöse Komplikationen. Daraus ergibt sich, daß trotz Antibiotikaprophylaxe das Auftreten infektiöser Komplikationen im Hospital do Desterro hoch ist.
Dr.Calais da Silva's discussion could not be presented during the meeting because of an unforeseen event, but the kindly provided us with this discussion. 相似文献
Dr.Calais da Silva's discussion could not be presented during the meeting because of an unforeseen event, but the kindly provided us with this discussion. 相似文献
43.
44.
BACKGROUND/AIMS: Hepatocytes (HEP) have been the major target for structural quantification in the liver, but an estimation of their total number (N), their percentage in relation to the global number of liver cells and the evaluation of the percentage of binucleated hepatocytes (BnHEPs) have never been performed with modern design-based stereological techniques. The establishment of sound technical guidelines and baseline quantitative data in non-pathological conditions are relevant to properly evaluate HEP hyperplasia and BnHEP responses. METHODS: In this study, we combined immunocytochemistry with sound design-based stereology for estimating the N of HEP and the N of non-hepatocytic cells (NHCs). For obtaining systematic uniform random sections (30 microm thick), a smooth fractionator sampling scheme was applied to the liver of five male Wistar rats (3 month old). Those sections were immunostained with polyclonal antibodies against carcinoembryonic antigen. Because biliary canaliculi were then marked, an unequivocal counting of mononucleated hepatocytes (MnHEP) and BnHEP was allowed. RESULTS: The N of HEP was estimated to be 1.93 x 10(9), with a coefficient of error (CE) of 0.02, corresponding to 129 x 10(6) HEP/g of liver. BnHEP represented 26% of total HEP number. The N of NHC was estimated as 1.31 x 10(9) (CE=0.02). CONCLUSION: The strategy here presented provides a reliable method for accessing the N of HEP (distinguishing MnHEP from BnHEP) in situations in which these parameters are relevant, namely for evaluating the magnitude of an hyperplastic liver response from its very early onset. 相似文献
45.
Guilherme Santoro-Lopes Erika Ferraz de Gouvêa Rodrigo Carreira M Monteiro Rodrigo Castelo Branco José Rodolfo Rocco Márcia Halpern Adriana Lúcia Pires Ferreira Elaine Gama Pessoa de Araújo Samanta T Basto Vinicius Gomes Silveira Joaquim Ribeiro-Filho 《Liver transplantation》2005,11(2):203-209
Methicillin-resistant Staphylococcus aureus (MRSA) is a frequent cause of infection after orthotopic liver transplantation (OLT). Colonization with MRSA is associated with a higher risk of infection. Previous studies have shown a high prevalence of MRSA colonization among OLT candidates. However, the risk of colonization with MRSA after OLT is still unclear. The objective of this study was to estimate the incidence and the factors associated with colonization with MRSA after OLT. This was a prospective cohort study including patients submitted to OLT between the years 2000 and 2002. Surveillance cultures of nasal swab specimens were performed within the 1st 72 hours of hospital admission and, subsequently, on weeks 2, 6, 13, and 26. Patients whose baseline cultures revealed nasal carriage of MRSA were excluded. A total of 60 patients were included in the study. The median follow-up was 72 days. A total of 9 patients (15%) became colonized. In multiple logistic regression analyses, the use of a urinary catheter for > or =5 days (P = .006), postoperative bleeding at the surgical site (P = .009), and preoperative use of fluoroquinolones (P = .08) were associated with a higher risk of colonization. Patients without any of these risk factors did not become colonized. In conclusion, nasal carriage of MRSA is frequently acquired after OLT. Periodic postoperative screening for MRSA carriage should be an integral component in programs designed to reduce nosocomial MRSA transmission in these patients. Further studies are needed to set up and validate a predictive model that could allow targeting postoperative screening to high-risk OLT recipients. 相似文献
46.
47.
Camila Oliveira Rodini Flávia Sirotheau Corrêa Pontes Hélder Ant?nio Rebelo Pontes Paulo Sérgio da Silva Santos Marina Gallottini Magalh?es Décio Santos Pinto 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(4):e50-e55
Leiomyosarcoma of the oral cavity is a very rare tumor associated with aggressive clinical behavior and low survival. In this paper, we report 2 cases of leiomyosarcoma, affecting the gingival mucosa of a 54-year-old female and the maxillary bone of a 63-year-old male. Histologically, the tumors were composed of variably oriented fascicles of spindle-shaped cells with cigar-shaped nuclei and eosinophilic cytoplasm. The lesions were treated by surgical resection. Immunoreactivity to anti-vimentin, anti-smooth muscle actin, anti-desmin, anti-laminin, and anti-muscle-specific actin antibodies were found; conversely, the tumor cells were negative for anti-S100 and AE1/AE3 proteins. This report emphasizes the role of immunohistochemical study for correct diagnosis of leiomyosarcoma. 相似文献
48.
Eduardo Kazuo Sannomiya Jun-ichi Asaumi Kanji Kishi Gisele da Silva Dalben 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(2):e41-e44
Dens invaginatus is a developmental variation resulting from an alteration in the normal growth pattern of the dental papilla. Synonyms of this disturbance include dens in dente, invaginated odontome, tooth inclusion, and dentoid in dente. Radiographically, it is observed as infolding of a radiopaque ribbon-like structure, with equal density as enamel, extending from the cingulum into the root canal and sometimes reaching the root apex, assigning the appearance of a small tooth within the coronal pulp cavity. This article presents 2 case reports. The first describes an 8-year-old girl with dens invaginatus in a mesiodens; the second report describes a 16-year-old boy presenting with 2 mesiodens, both associated with dens invaginatus. 相似文献
49.
Mariela Dutra Gontijo Moura Tatiane Roberta Morais Guimar?es Linaena Méricy Silva Fonseca Isabela de Almeida Pordeus Ricardo Alves Mesquita 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,103(1):64-71
OBJECTIVE: The objective of this study was to assess the efficiency of topical applications of podophyllin resin (25%) (P) versus podophyllin resin (25%) together with acyclovir cream (5%) (PA) in the treatment of oral hairy leukoplakia (OHL) in accordance with the following criteria: (1) number of applications necessary for the total clinical resolution of OHL; (2) correlation between the decrease of lesion size and the number of applications; (3) total clinical resolution of OHL; and (4) clinical reevaluation 12 months after the end of treatment. STUDY DESIGN: Forty-six OHLs were treated with P (P group) or with PA (PA group). Applications were performed weekly. Student t, Fisher exact, and Pearson correlation tests were used for statistical analysis. RESULTS: All 24 lesions from the PA group presented total clinical resolution while 4 lesions from the P group did not. The P group required up to 25 applications performed weekly while the PA group required up to 18. Observed was a negative significant association between the size of the lesions and the number of applications performed weekly in the PA group. CONCLUSIONS: The present study demonstrated the following: (1) P and PA topical treatments presented a similar average number of applications performed weekly; (2) both groups showed the same clinical response at 12 months post-therapy; and (3) PA presented a 100% clinical resolution and a continuous decrease in OHL size over the course of weekly applications. 相似文献
50.
Edmo Atique Gabriel Rafael Fagionato Locali Carla Cristina Romano Alberto José da Silva Duarte José Honório Palma Enio Buffolo 《European journal of cardio-thoracic surgery》2007,31(3):406-412
OBJECTIVE: The objective of this study is to evaluate the inflammatory response caused by endovascular stents in the treatment of aortic aneurysms. METHODS: Twenty-five patients underwent endovascular stent treatment from March through December 2005. The evolution of mediators (sedimentation velocity, C reactive protein, interleukin-6, interleukin-8, tumor necrosis factor-alpha, intercellular adhesion molecule-1, l-selectin), inflammatory cells (leukocytes, lymphocytes, platelets), serum creatinine and body temperature within preoperative period and in the following postoperative periods--1, 6, 24 and 48 h, 7 days, 1-3 months, was analyzed. In order to achieve statistic significance, Friedman test and Wilcoxon test were used, with index of significance of 5% (p<0.05). RESULTS: Peak values of sedimentation velocity, C reactive protein and interleukin-6 were observed at 7 days (p<0.0001), 48 h (p<0.0001) and 24h (p<0.0001), respectively. Tumor necrosis factor-alpha and interleukin-8 did not show statistically significant variability during the entire follow-up. In terms of intercellular adhesion molecule-1 and l-selectin, their expressive values were found in late phase of follow-up, although without statistical significance. Elevation of leukocytes count occurred in premature phase of follow-up (p<0.0001), while lymphocyte and platelet count occurred in a late phase of follow-up (p<0.0001). Serum levels of creatinine did not show significant variability during follow-up. The period between 24 and 48 h corresponded to major frequency for fever (p<0.0001). CONCLUSION: Individual mediators analysis and inflammatory cells demonstrated variability of their values during postoperative follow-up. This could help in the analysis of the inflammatory response evolution caused by endovascular stent treatment for aortic aneurysms in premature and late phases after implantation of the vascular prosthesis. 相似文献