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61.
The presence of vascular permeability factors in the extracellular products (ECP) of 10 strains of Renibacterium salmoninarum with different geographical origin and serological characteristics are reported. All the ECP produced haemorrhagic and/or oedematous zones at the injection site with a diameter ranging from 10-30 mm. However, the ECP samples did not display toxic effect in fish at the same dose as inoculated in rabbit (180-400 micrograms protein/0.1 ml). No differences were observed in the production of this dermatotoxic factor between the two antigenic groups found in this microorganism. Whereas heating (80 and 100 degrees C/15 min) the ECP samples resulted in a complete loss of their proteolytic activity, only a decrease (but not total inactivation) of the dermatotoxic effects was detected. Therefore, although proteases could be implicated in the permeability factor, they are not totally responsible for this activity. 相似文献
62.
J N dos Santos A M e Silva P Alexandrino T Saldanha M O Carrageta E Ferreira F de Pádua 《The Netherlands journal of medicine》1991,38(5-6):212-216
Inherited defects of the natural coagulation inhibitors predispose patients to thrombosis. These disorders have similar clinical presentations with a strong family history of thrombosis, episodes of recurrent venous thromboembolism, beginning in early adulthood. We report a case of upper gastrointestinal bleeding in a patient with portal hypertension due to portal-vein thrombosis secondary to hereditary protein C deficiency, an association that has seldom been reported. 相似文献
63.
Mark Hans Emanuel M.D. Augustinus Hart M.Sc. Kees Wamsteker M.D. Frits Lammes M.D. 《Fertility and sterility》1997,68(5):881-886
Objective: To determine the contribution of several variables to fluid loss during transcervical resection of submucous myomas.Design: An observational study using multiple linear regression analyses.Setting: A university-affiliated training hospital and a university department of clinical epidemiology and biostatistics.Patient(s): Patients with submucous myomas.Intervention(s): Transcervical resection of submucous myomas and monitoring of fluid loss.Main Outcome Measure(s): Patient age, uterine enlargement, treatment with GnRH analogues or 8-ornithine-vasopressin, type of anesthesia, number of myomas, intramural extension of the myoma (type of myoma), and operating time were tested as variables.Result(s): Only intramural extension of the myoma and operating time were obviously related to fluid loss. For the other variables, such a relation was weak at best. The relation between fluid loss and operating time was not modified by any of the other variables.Conclusion(s): Because fluid loss is an important limiting factor in the transcervical resection of submucous myomas, special attention should be paid to reduction of the operating time and preoperative assessment of the intramural extension of the myoma to guide appropriate patient selection. 相似文献
64.
The authors present the third installment of the guidelines and recommendations from the Safety Committee of the Society for Magnetic Resonance Imaging (now the Society of Magnetic Resonance) concerning various issues related to the safety and management of patients undergoing magnetic resonance (MR) procedures. This document was developed to provide standardized and consistent information for use by health practitioners involved in screening patients or other individuals for MR procedures. 相似文献
65.
John Hill Robert C. Stuart Hin K. Fung Enders K.W. Ng Fanny M. Cheung Sidney C.S. Chung C. Andrew van Hasselt 《The Laryngoscope》1997,107(10):1373-1377
The aim of this study was to investigate the origin of globus pharyngis with particular reference to esophageal disorders such as gastroesophageal reflux disease (GERD), motility disorders, structural abnormalities, other gastrointestinal tract diseases, and psychological profile. Previous studies on this subject using 24-hour pH monitoring give conflicting results and are hampered by the high background prevalence of asymptomatic GERD in the normal Western population. The local Chinese population is known to have a very low background level of GERD and therefore is an ideal study population. Twenty-six patients with globus pharyngis underwent 24-hour ambulatory pH monitoring, esophageal manometry, and esophagogas-troduodenoscopy with lower esophageal biopsy. A control group of 20 patients presenting with non-ulcer dyspepsia was similarly investigated. Personality profiles of the globus pharyngis subjects and an appropriate control group were assessed. Eight of the globus pharyngis group (30.7%) had evidence of GERD, whereas only one of the controls (5%) demonstrated GERD on 24-hour esophageal pH monitoring (P < 0.05). The manometric and personality profile studies did not show significant differences between study and control groups. We concluded that the finding of GERD in patients with globus pharyngis is not a coincidental finding but that there is a true association between GERD and globus pharyngis. 相似文献
66.
F. Veiga Fernandes J. Coutinho M. P. Henriques B. da Silva A. Baptista A. I. Santos F. Godinho 《Transplant international》1992,5(Z1):S193-S195
A new technique of choledochoenterostomy was devised to solve some of the problems of enterobiliary anastomosis with a normal calibre. The distal extremity of the common bile duct is completely surrounded by the bowel mucosa to a length of 3 cm after seromyectomy of a bowel wall rectangle of 4 × 1 cm. Experimental studies in rats and dogs demonstrated that this procedure prevents the risks of anastomotic disruption and functions like a mechanical unidirectional valve, which has great efficacy in stopping enterobiliary reflux. Studies in ten patients with obstructive jaundice with an extrahepatic biliary dilation less than 1.2 cm diameter submitted to this procedure Confirmed the experimental results. All patients were asymptomatic, without jaundice and with normalization of the liver enzymes after 2 months. The permeability of the valvular anastomosis studied by cholangiography, the HIDA 99mTc test and manometry was quite similar to other classical biliary-enteric anastomosis. In contrast, anti-reflux efficacy was only demonstrated in patients with a valvular anastomosis. 相似文献
67.
Felipe A. Calvo David Ortiz de Urbina Luis Sierrasesúmaga Oscar Abuchaibe Ignacio Azinovic Federico Antillon Manuel Santos Jos Canadell 《Pediatric blood & cancer》1991,19(6):478-485
From September 1984 to December 1989, 38 patients of pediatric age with localized bone sarcomas received intraoperative radiotherapy (IORT) as part of a multidisci plinary treatment program. The age ranged from 6 to 21 years. The tumor histologies were 22 osteosarcomas and 16 Ewing's sarcomas. Thirty-four had initial primary disease (90%) and 4 were treated for local recurrence (10%). IORT was used on 32 untreated patients and in 6 previously treated with external beam radiotherapy (EBR). The IORT field included the surgically exposed tumor bed area. Single radiation doses ranging from 10 to 20 Gy were delivered, using 6–20 MeV electron beams. The median follow-up time for the entire group is 25 months (2–65+ months). The projected 5-year disease-free and overall survival rates are 65% and 69%, respectively. One patient developed a local recurrence in each histological group: one chondroblastic osteosarcoma and one cervical Ewing's sarcoma. Six patients died from metastatic progression: 3 initially recurrent tumors and three primary disease cases. Severe neuropathy and soft tissue necrosis were seen in some patients as IORT related complications. IORT is a feasible technique to be integrated in multidisciplinary programs that may promote local control in pediatric and adolescent patients with bone sarcomas. Peripheral nerves are dose-limiting tissue structures for IORT. 相似文献
68.
A Oehling B García F Santos H Córdoba I Diéguez M Fernández M L Sanz 《Journal of investigational allergology & clinical immunology》1992,2(2):78-83
We studied the histories of patients who had visited our Department during the last 5 years, presenting food allergy with exclusively respiratory symptoms (18.5%). We studied the correlation between IgE levels and the histamine release test and the type of food implicated. Seventy-seven percent of patients presented sensitization to one food, and 23% presented polysensitization. We found that foods such as snails and eggs have a strong predilection for the bronchial tree as the shock organ. High total IgE was found in 85.2% of patients. The histamine release test was positive in 66% of cases. We conclude that this is a highly sensitive method for the in vitro diagnosis of food allergy. 相似文献
69.
Andrew P. Thomas Dennis J. Rozanski Dominique C. Renard Emanuel Rubin 《Alcoholism, clinical and experimental research》1994,18(1):121-131
Chronic ethanol consumption leads to a number of alterations in the contractile function of the heart and is a leading cause of cardiomyopathy. Ethanol also has an acute negative inotropic effect mediated by direct interaction with cardiac muscle cells, although this action is often masked by indirect actions resulting from enhanced release of catecholamines in vivo. This article reviews the effects of ethanol on the contractile function of the heart. The specific targets affected by ethanol in cardiac muscle cells are discussed in terms of potential mechanisms underlying the depressions of contractility resulting from both acute and chronic actions of ethanol. 相似文献
70.
Nuno Fonseca Filomena Caetano José Santos Filipe Seixo Leonel Bernardino Isabel Silvestre Paula Cardoso Filomena Segurado Lopes Inês 《Revista portuguesa de cardiologia》2004,23(3):365-375
INTRODUCTION: In patients (pts) with atrial fibrillation (AF) of more than 48 hours' duration, electrical cardioversion (ECV) should only be performed after 3 weeks of effective anticoagulation. Transesophageal echocardiography (TEE) allows earlier ECV; however, despite exclusion of thrombi in the atrium and left atrial appendage (LAA), cases of thromboembolism related to ECV have been documented in AF. To define a low-risk group for cardioversion without previous anticoagulation, pts were selected for immediate ECV if no thrombi or dynamic spontaneous echo contrast (auto-contrast) were found after TEE and if LAA velocity was more than 0.25 m/sec. METHODS AND RESULTS: We performed TEE in 31 consecutive pts referred for ECV for AF of more than 48 hours' duration and without previous anticoagulation. After TEE the pts eligible for immediate ECV began anticoagulation with low molecular weight heparin (enoxaparin), subcutaneously in therapeutic doses, together with warfarin immediately before cardioversion. Enoxaparin was continued until an INR of over 2 was reached. Based on the TEE findings, the pts were divided in 2 groups: immediate ECV, group A, 20 pts with a mean age of 62 +/- 13 years, 6 female; and conventional therapy with warfarin before ECV, group B, 11 pts, mean age of 67 +/- 10 years (p < 0.05), 2 female. None of the pts in either group had mitral stenosis or previous episodes of thromboembolism. The mean transverse diameter of the left atrium in the 31 pts was 47 +/- 4.5 mm, without statistically significant differences between the 2 groups. Of the 11 pts in group B, 3 had a thrombus in the LAA, 6 dynamic spontaneous echo contrast and the remainder LAA velocities of less than 0.25 m/sec. ECV was achieved in all the pts, with no complications. Oral anticoagulation was maintained for at least a month. At one month, sinus rhythm was maintained in 75% of group A and 45% of group B (p < 0.01). CONCLUSION: In pts with AF of more than 48 hours' duration and no previous history of thromboembolism, the use of our exclusion criteria during TEE enabled stratification of a low-risk population for immediate ECV, which was accomplished effectively and safely in 2/3 of the pts. This strategy is associated with early symptomatic improvement, and may contribute to maintenance of sinus rhythm after one month, which was significantly better than in the pts who had prolonged therapy with warfarin before ECV, despite the differences found in age and left ventricular function. 相似文献