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Neurologic outcome after heart transplantation in Chagas' disease   总被引:1,自引:0,他引:1  
Objective - To evaluate the neurologic morbidity after orthotopic heart transplantation (OHT), we examined consecutive Chagas' (Ch) and non-Chagas' (NCh) patients, before and after surgery. Material and methods - We undertook neurological and neuropsychological evaluations in Ch and NCh patients with end-stage cardiac failure, from September 1993 to September 1995. Results - Of 10 Ch patients (mean age=33.6 years; 7 male; mean follow-up=10.8 months) and 13 NCh patients (mean age=50.9 years; 12 male; mean follow-up=15 months) 3 died (rejection and sepsis) without neurologic symptoms. Neurologic complications occurred in 4 Ch and 5 NCh patients. Two Ch patients had skin and myocardial Chagas' reactivation successfully treated, without CNS involvement. NPS performance and return to work rates were similar in both groups. Conclusions - Although Ch patients are potentially at a higher risk of Trypanosoma cruzi reactivation, in addition to all known neurologic complications of OHT, early neurologic complications detected in this sample were similar in Ch and NCh patients and could not be specifically related to Chagas' disease.  相似文献   
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The in vitro release of LHRH from hypothalami of adult male rats (intact, 5-day castrates, 5-day castrates replaced with various doses of testosterone) was measured under basal conditions and after the addition of KCl, the opiate antagonist naloxone or the opiate agonist DAGO to the perifusion medium. Hypothalami from all treatment groups responded to 56 mM KCl with an increased output of LHRH. LHRH release was also induced by naloxone (10(-6)M), but only from tissues derived from intacts and castrates given physiological doses of testosterone. The opiate agonist DAGO (10(-6)M) did not alter the basal release of LHRH; it, however, caused a significant decrease in the K+-induced release of LHRH from hypothalami derived from intact rats and rats replaced with physiological levels of testosterone but not from those derived from castrate rats or castrate rats replaced with small amounts of testosterone. The specificity of this latter response was shown by its reversibility with naloxone. The lack of DAGO effects upon tissues from rats with low levels of steroid implied steroid dependency of the response to opioidergic influences and indeed, the response to DAGO was restored when testosterone was replaced at physiological doses. Measurement of hypothalamic LHRH content showed no significant differences between tissues obtained from intact, castrate and testosterone-replaced castrate rats. These in vitro data support the view that the inhibitory influence of opioids upon LHRH release depends on the presence of gonadal steroids in vivo.  相似文献   
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Uroscopy in the 21st century: high-field NMR spectroscopy   总被引:1,自引:1,他引:0  
From the experiments described, it can be seen that there are different research approaches that can be taken and these are summarized in Table 1. Whereas much scientific research is principally hypothesis led, there remains, nevertheless, an important place for exploratory research. High resolution NMR can measure, directly and simultaneously, a wide range of endogenous metabolites in biological fluids and has the unique capability of providing structural information on the metabolites detected. It has proved to be a powerful research tool with which to study inherited metabolic diseases, renal disease, drug metabolism, and toxicity, and can be used to monitor the effects of drug therapy. For instance, by using a library of experimental toxins one can map the metabolic profile of site-specific nephron injury. With this approach in man one could eventually take an unknown disease such as Balkan nephropathy and predict the initial site of tubular injury, the mode of injury and therefore the kind of toxin capable of producing that injury. NMR spectroscopic techniques are still advancing rapidly, with ever increasing sensitivity and sophistication of NMR pulse sequences to enhance structural elucidation in complex mixtures. Given the advances in directly coupled HPLC-NMR and even HPLC-NMR-mass spectroscopy it is likely that these technologies in conjunction with pattern recognition will make major contribution to our understanding of renal processes and provide new diagnostic insights in the 21st century.   相似文献   
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The author presents 83 cases of "a frigore" peripheral facial palsy, occurred in the mountain city of Petropolis which has characteristics such as a tropical climate without any traces of a dry season and an average temperature of 50 degrees F to 73.5 degrees F. The author relates them with virus infections which appear within a year period. Fifty six patients belong to his clinic and have a follow up, while other 25 patients proceed from another clinics and from them he only has reports on sex, age, side of palsy and the beginning of illness. He shows that the largest number of cases occurred along the months of May, August, September and October. Season distribution for southern hemisphere is analysed. He also considers etiology, incidence, prevalence, treatment and results on patients studied.  相似文献   
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Owing to the large size of the APC gene, responsible for familial adenomatous polyposis, direct screening for individual mutations is not a practical approach. In the present study we establish the methodology of fluorescence based semi-automated DNA analysis to perform presymptomatic diagnosis of members at risk from 11 Portuguese FAP families with three (CA)n markers flanking the APC gene, MBC, CB26, and YN5.64, and four intragenic RFLPs. Haplotypes were constructed on the basis of individual genotypes and their segregation through generations were followed. The study was informative for 12% of subjects using only intragenic RFLPs and increased to 90% when we used the three (CA)n flanking markers. We report two of the 11 families under study in our laboratory and show recombinant events leading to a precise localisation of the CB26 marker between D5S82 and the APC gene. In one family there was a loss of (CA) units of one allele of the CB26 marker from an unaffected mother to her son.  相似文献   
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