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51.
BACKGROUND: Heart transplantation (HT) as a therapeutic option for end-stage chronic Chagas' heart disease (CCHD) is controversial. Reactivation of Trypanosoma cruzi infection and recurrence of the disease in the allograft are likely to occur. Furthermore, active myocarditis has been reported to predispose patients to an increased incidence and severity of rejection. METHODS AND RESULTS: We prospectively investigated the long-term follow-up of 10 patients with CCHD who underwent HT. Immunosuppression was based on cyclosporine A and azathioprine. T cruzi reactivation was prevented with benzonidazole. Besides allograft rejection surveillance, T cruzi infection was monitored through blood tests, myocardial biopsies, and serological tests. Over a mean follow-up period of 34 +/- 38 months (range, 73 to 124 months), 7 patients are alive and in NYHA functional class I. Life expectancy was 78% for the second year and 65% for 10 years. Rejection was less frequent in chagasic than in age- and sex-matched control patients (mean +/- SD, 1.60 +/- 1.26 versus 5.70 +/- 1.89 episodes per patient, respectively; P = .0001); decreased severity of rejection was also observed (P = .006). T cruzi parasitemias detected on three occasions were successfully treated with benzonidazole. There were no signs of recurrence of the disease in the allograft. CONCLUSIONS: These results suggest an important role of HT in the treatment of CCHD. There was a low frequency of T cruzi infection reactivation and no signs of recurrence of the disease in the allograft. The surprisingly decreased rejection incidence and severity require further studies for elucidation.  相似文献   
52.
We evaluated the occurrence of abnormalities in paranasal sinus radiographs in acute asthma by taking a radiograph of the sinuses of 110 consecutive patients admitted to a medical ward a total of 149 times for asthma. Maxillary sinus infection was assessed by taking aspirate from radiologically abnormal maxillary sinuses. An abnormal finding in any paranasal sinus was detected on 87% (130 of 149) of admissions and the yield of maxillary aspirate was macroscopically mucous, purulent or mucopurulent in 60% (42 of 70) of aspirates. A positive bacteriological culture was obtained from 23 aspirates and a virus was detected in 15, there being 7 aspirates in which both a bacterium and a virus could be detected. Although the correlation between radiographic findings and the aspirates was not very close we conclude that radiographic abnormalities of the paranasal sinuses are common in acute asthma as are infections of maxillary sinuses with an abnormal radiographic finding. There is an obvious need to look for sinusitis when a patient with an exacerbation of asthma is being evaluated.  相似文献   
53.
1. The aim of the present study was to characterize neurogenic and pharmacological responses of human penile deep dorsal vein and to determine whether the responses are mediated by nitric oxide from neural or endothelial origin. 2. Ring segments of human penile deep dorsal vein were obtained from 22 multiorgan donors during procurement of organs for transplantation. The rings were suspended in organ bath chambers for isometric recording of tension. We then studied the contractile and relaxant responses to electrical field stimulation and to vasoactive agents. 3. Electrical field stimulation (0.5-2 Hz) and noradrenaline (3 x 10(-10)-3 x 10(-5) M) caused frequency- and concentration-dependent contractions that were of greater magnitude in veins denuded of endothelium. The inhibitor of nitric oxide synthesis NG-nitro-L-arginine methyl ester hydrochloride (L-NAME, l0(-4) M) increased the adrenergic responses only in rings with endothelium. 4. In preparations contracted with noradrenaline in the presence of guanethidine (10(-6) M) and atropine (10(-6) M), electrical stimulation induced frequency-dependent relaxations. This neurogenic relaxation was prevented by L-NAME, methylene blue (3 x 10(-5) M) and tetrodotoxin (10(-6) M), but was unaffected by removal of endothelium. 5. Acetylcholine (10(-8)-3 x 10(-5) M) and substance P (3 x 10(-11) -3 x 10(-7) M) induced endothelium-dependent relaxations. In contrast, sodium nitroprusside (10(-9)-3 x 10(-5) M) and papaverine (10(-8) 3 x 10(-5) M) caused endothelium-independent relaxations. 6. The results provide functional evidence that the human penile deep dorsal vein is an active component of the penile vascular resistance through the release of nitric oxide from both neural and endothelial origin. Dysfunction in any of these sources of nitric oxide should be considered in some forms of impotence.  相似文献   
54.
Using linguistic values to assess results and information about external factors is quite usual in real decision situations. In this article we present a general model for such problems. Utilities are evaluated in a term set of labels and the information is supposed to be a linguistic evidence, that is, is to be represented by a basic assignment of probability (in the sense of Dempster-Shafer) but taking its values on a term set of linguistic likelihoods. Basic decision rules, based on fuzzy risk intervals, are developed and illustrated by several examples. the last section is devoted to analyzing the suitability of considering a hierarchical structure (represented by a tree) for the set of utility labels. © 1992 John Wiley & Sons, Inc.  相似文献   
55.
A case of a 55-year-old man was remitted to Traumatology Department to present back pain of two weeks of evolution. The results of bone scintigraphy and the patient's evolution allowed the diagnosis. This case report and a literature review showed the importance of using a routine bone scan in diagnosis of bone metastases.  相似文献   
56.
After more than a decade of special treatment, HIV medicine is ready to enter the mainstream of medical practice in developed countries. Access to a conveniently located, well informed, primary care doctor who works well with an appropriate specialist is the cornerstone of best medical care for chronic illness, including HIV disease. Managing HIV is part of the second phase of a national educational program aimed at equipping more doctors with the skills to care for people with HIV.  相似文献   
57.
OBJECTIVE: To analyze the contribution of clinical trials in the hospital treatment of acute ischaemic cerebrovascular disease. DEVELOPMENT: In recent studies many trials have been designed for the treatment of the acute phase of this illness. Based on experimental studies, the drugs used in the trial need to be given within a 'therapeutic window' of less than six hours from the onset of the illness. This time factor has led to a radical change in the organization of hospital services dealing with this illness. In order to run clinical trials the medical staff have had to be organized into functional stroke units for the swift protocolized diagnosis of the condition. Also information has to be given to health workers regarding the need for urgent specialized treatment. Several studies have shown that early, specialist treatment reduces morbi-mortality, time spent in hospital and financial cost in these patients. CONCLUSION: Clinical trials in acute cerebrovascular pathology have formed the basis for the creation of stroke units, led to the drawing up of protocols for the diagnosis and guidelines for treatment. It has also made the medical profession more aware of the importance of early diagnosis and specialized treatment in acute cerebral ischaemia.  相似文献   
58.
1. The adaptational changes induced after chronic desipramine treatment on functional responsiveness of alpha 2-adrenoceptor activation were investigated in prostatic portions of the rat vas deferens. 2. For this purpose, clonidine and xylazine were studied for their effects on twitch contractions elicited by electrical field stimulation of prostatic portions removed 48 h after the last injection to the animals of vehicle or desipramine (10 mg kg-1, i.p.; 14 days). Operational model-fitting and the nested hyperbolic method were used to analyse the effects of irreversible receptor alkylation by N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ, 300 nM) on the alpha 2-adrenoceptor-mediated effects of clonidine, either in vehicle- or in desipramine-treated animals. 3. Treatment with desipramine decreased the potency (increased the EC50) of clonidine and xylazine by about 12 and 9 fold respectively. However, the treatment did not modify the maximal effect (alpha) elicited by either agonist. The estimates of apparent affinity for clonidine did not depend on the method of calculation as the 'null' method and the 'operational' method gave similar answers. Estimates of tau values for both agonists revealed that chronic desipramine treatment resulted in significant decreases in the efficacy of agonists. However, desipramine treatment was not associated with significant changes in the affinity constant for clonidine while for xylazine, the operational model provided a higher estimate of KA (lower affinity) after desipramine treatment. 4. The results indicate a large receptor reserve at prejunctional alpha 2-adrenoceptors which is modulated by chronic desipramine treatment. 5. The comparison of results obtained after chronic desipramine exposure with those by using EEDQ suggests that chronic desipramine treatment is not a useful experimental intervention for the purpose of estimating agonist affinities and efficacies.  相似文献   
59.
Three new cases of two different forms of congenital nemaline myopathy are reported. Two of them represent a severe neonatal form. These cases were presented as a floppy infant syndrome. Although neither of them needed intensive care, they had feeding difficulties and one needed a feeding-tube for a period of time. Both of the patients showed a very severe motor delay and neither could manage to walk independently. During their lives, they suffered from repeated pneumonias, which was the cause of death in both cases before the age of two years. The mild congenital type represents a more benign form. Although hypotonic and weak, the patient managed to walk independently before two years of age. The weakness was spread all over, but was focused in the face, extensors of the neck and axial muscles. At 9 years of age, the patient has not experienced any respiratory trouble. The CK (creatine kinase) test were normal in all patients, but the EMG (electromyogram) showed different electromyographic patterns. The rods were in subsarcolemic positions, cytoplasmic positions or in both positions.  相似文献   
60.
In this study, it is presented for the first time, the characterization of an amorphous polyamide after having been subjected to humid thermal conditions such as those typically applied in the industrial sterilization of packaged foods. From a fundamental point of view, it was fortuitously found that the combination of heat and moisture, with and without the assistance of pressure, was capable of inducing some crystallization in the otherwise amorphous polymer. Characterization of the crystallization process was carried out by differential scanning calorimetry, Fourier transform infrared, and simultaneous time‐resolved small and wide angle X‐ray scattering synchrotron experiments. The crystallization of the polymer began as characterized by wide angle X‐ray scattering and differential scanning calorimetry in the presence of humidity at ~90°C and extended up to 120°C under autoclave conditions, and it is thought to be the result of heated moisture being able to disrupt the intense amide groups self‐association. Thus, the thermally activated molecular structure is thought to become plasticized by the combined presence of heat and water which, in turn, provoke sufficient segmental molecular mobility in the system to promote some degree of lateral order. Propertywise, the resulting consequences of this behavior are an increase in the barrier properties to oxygen and a reduction in water sorption. From an applied view point, it is suggested that this unexpected behavior could make this polymer of significant interest in retortable food packaging applications. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1216–1223, 2006  相似文献   
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