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961.
    
BACKGROUND: The benefit of coarctation repair in adults has been questioned by suggesting that hypertension may not be relieved by the operation and that surgical intervention may have no impact on the natural history of the disease. METHODS: To delineate the impact of surgical intervention on systolic hypertension, we conducted a retrospective review of 26 adults with a mean age of 32 +/- 10 years who underwent coarctation repair between 1987 and 1993. All patients were hypertensive (mean systolic blood pressure, 174 +/- 21 mm Hg; range, 140 to 220 mm Hg), and 18 patients (69%) were on a regimen of at least one hypertensive medication at the time of surgical admission. All patients underwent catheterization, and the mean peak systolic gradient across the coarctation was 61 +/- 25 mm Hg (range, 25 to 120 mm Hg). Operation included resection and end-to-end anastomosis (3 patients), resection with an interposition tube graft (6 patients), a bypass graft (11 patients), and patch angioplasty (6 patients). There was no hospital mortality or late morbidity. RESULTS: Intermediate follow-up was available at a mean of 2.3 +/- 2 years (range, 1 to 7 years). At last follow-up, the peak systolic gradient between the upper and lower body was trivial (< or = 10 mm Hg) in 23 patients (88%) and mild (11 to 20 mm Hg) in 3 (12%). All patients had significant improvement in systolic blood pressure (p < 0.001) compared to preoperative values, and the majority (23, 88%) were normotensive. More than half of the patients (14, 54%) were still on a regimen of antihypertensive medication at last follow-up, with a trend (p = 0.06) toward older patients requiring medication. CONCLUSIONS: Surgical repair of coarctation in adults is an effective, low-risk procedure, which results in a significant improvement in systolic hypertension and a decreased requirement of antihypertensive medications.  相似文献   
962.
    
Enzyme immunoassay (EIA) with sixty types of monoclonal antibodies (MAbs) was used to study cross-reactive epitopes on the attenuated and virulent strains of the Eastern equine encephalomyelitis (EEE) and Venezuelan equine encephalomyelitis (VEE) viruses. All three structural proteins of the EEE and VEE viruses were demonstrated to have both cross-reactive and specific antigenic determinants. The glycoprotein E1 of EEE and VEE viruses possesses three cross-reactive epitopes for binding to MAbs. The glycoprotein E2 has a cluster of epitopes for 20 cross-reacting MAbs produced to EEE and VEE viruses. Cross-reactive epitopes were localised within five different sites of glycoprotein E2 of VEE virus and within four sites of that of the EEE virus. There are no cross-neutralising MAbs to the VEE and EEE viruses. Only one type of the protective Mabs was able to cross-protect mice against lethal infection by the virulent strains of the VEE and EEE viruses. Eight MAbs blocked the hemagglutination activity (HA) of both viruses. Antigenic alterations of neutralising and protective sites were revealed for all attenuated strains of the VEE and EEE viruses. Comparative studies of the E2 proteins amino acid sequences show that the antigenic modifications observed with the attenuated strains of the VEE virus may be caused by multiple amino acid changes in positions 7, 62, 120, 192 and 209-213. The escape-variants of the VEE virus obtained with cross-reactive MAbs 7D1, 2D4 and 7A6 have mutations of the E2 protein at positions 59, 212-213 and 232, respectively. Amino acid sequences in these regions of the VEE and EEE viruses are not homologous. These observations indicate that cross-reactive MAbs are capable of recognising discontinuous epitopes on the E2 glycoprotein.  相似文献   
963.
PURPOSE: To test whether physician's diagnostic inferences can be improved by communicating information using natural frequencies instead of probabilities. Whereas probabilities and relative frequencies are normalized with respect to disease base rates, natural frequencies are not normalized. METHOD: The authors asked 48 physicians in Munich and Düsseldorf to determine the positive predictive values (PPVs) of four diagnostic tests. Information presented in the four problems appeared either as probabilities (the traditional way) or as natural frequencies. RESULTS: When the information was presented as probabilities, the physicians correctly estimated the PPVs in only 10% of cases. When the same information was presented as natural frequencies, that percentage increased to 46%. CONCLUSION: Representing information in natural frequencies is a fast and effective way of facilitating diagnosis insight, which in turn helps physicians to better communicate risks to patients, and patients to better understand these risks.  相似文献   
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966.
A case of Goodpasture's syndrome in a patient of 26 is described. The disease mainly involved the lungs and the kidneys. The development of the pneumo-renal syndrome in the patient was favoured by the occurrence of chronic focal diseases (rhinitis, otitis, sinusitis) which created opportunities for long-term microbial sensitization of the organs.  相似文献   
967.
On the basis of 24 cases reported in the literature and 2 personal observations of the authors the indications for surgical correction of a single ventricle of the heart are discussed. Two different surgical techniques are described: 1) haemodynamic correction of the defect comprising a closure of the venous atrioventricular valve, oversewing the proximal pulmonary artery, and anastomosing the right atrium and the distal pulmonary artery; 2) radical correction--creation of the ventricular septum. The variants of the disease permitting a radical correction are indicated, the results of surgery, the causes of complications and mortality are discussed.  相似文献   
968.
969.
The authors present a work intended to assess the effects of lumbar sympathectomy using radioactive microspheres. These contain 99mTe and are injected into the femoral artery. The distribution of radioactivity is then measured at the lower limb with a gamma camera linked to a computer. Seventeen patients were tested before and after lumbar sympathectomy. It appears from this short series that lumbar sympathectomy causes a redistribution of the radioactive material directed towards the extremities, mainly the feet.  相似文献   
970.
    
Cowpea (Vigna unguiculata) is a very important crop for people living in the north‐east of Brazil where it constitutes the principal source of protein and carbohydrate. In this study, it was observed that the in vitro digestibility of the seed albumin and globulin fractions extracted from eight Brazilian cowpea cultivars was high when treated with pepsin but resistant to degradation by trypsin or chymotrypsin even after 3 h of treatment. When the albumin and globulin fractions were given to rats by intragastric intubation it was observed that intact proteins or their fragments were immunodetected in the faeces. Immunohistochemical analyses of the gut sections of these rats showed that a proportion of the albumin fraction (or its fragments), but not the globulin one, was bound to the brush border enterocytes in the duodenum. Thus the incomplete enzymatic degradation of both globulin and albumin fractions as well as the albumin binding to the gut may have a bearing upon the growth depression, malabsorption and diarrhoea observed on rats fed on cowpea seeds. Copyright © 2004 Society of Chemical Industry  相似文献   
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