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OBJECTIVE: To compare the tolerability of angiotensin-converting enzyme (ACE) inhibitors with that of angiotensin II (AII)-receptor blockers and the incidence of cough and angioedema associated with their use through review of published data. DATA SOURCES: References were identified through a MEDLINE search of articles published between January 1975 and April 1997. Bibliographies of pertinent references were also reviewed. RESULTS: Results of placebo-controlled and comparative trials of the AII blockers demonstrate that they are at least as effective as ACE inhibitors for hypertension, but exhibit an incidence of cough and absent or rare angioedema like that of placebo. CONCLUSIONS: In the 10 comparative trials described, all reported a lower incidence of cough with AII blockers than with ACE inhibitors. Angioedema was not reported in the comparative trials described.  相似文献   
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In six normal subjects forced expiratory flow rates increased progressively with increasing degrees of chest strapping. In nine normal subjects forced expiratory flow rates increased with the time spent breathing with expiratory reserve volume 0.5 liters above residual volume, the increase being significant by 30 s (P less than 0.01), and flow rates were still increasing at 2 min, the longest time the subjects could breathe at this lung volume. The increase in flow after low lung volume breathing (LLVB) was similar to that produced by strapping. The effect of LLVB was diminished by the inhalation of the atropinelike drug ipratropium. Quasistatic recoil pressures were higher following strapping and LLVB than on partial or maximal expiration, but the rise in recoil pressure was insufficient to account for all the observed increased in maximum flow. We suggest that the effects of chest strapping are due to LLVB and that both cause bronchodilatation.  相似文献   
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BACKGROUND: Cyclosporine A (CYA) is primarily utilized as an immunosuppressant, but its mechanisms of action (including decreased neutrophilic free radical production and stabilization of mitochondrial and lysosomal membranes) may have beneficial effects in ischemia and reperfusion (IR) injury. This study was undertaken to examine the effect of CYA pretreatment on porcine liver histopathologic changes and enzymatic release caused by ischemia and reperfusion. MATERIALS AND METHODS: CYA was administered orally for 4 days prior to surgery in two doses (10 or 20 mg/kg) while controls received only the control vehicle. Pigs were then exposed to 4 h of hepatic ischemia followed by 2 h of reperfusion. RESULTS: Significant decreases in AST levels compared to controls were seen in high dose CYA pigs at the end of ischemia and at 30-min intervals during the reperfusion period. Controls exhibited necrotic hepatocytes and severe inflammatory cell infiltration, while high dose CYA animals demonstrated mild inflammatory cell infiltrates. Controls had decreased survival--20% did not survive reperfusion. CONCLUSIONS: This study indicates that CYA may be useful in decreasing initial damage resulting from warm hepatic IR injury.  相似文献   
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Lateral pharyngotomy offers good exposure for the removal of many laryngeal and hypopharyngeal tumors. The simplified operation I present avoids damage to voice, deglutition or airway. This approach can be expanded to reach almost any tumor of the pharynx and radical neck dissection can be incorporated. The cosmetic result has been satisfactory, but if individual consideration prompts it, a more horizontal skin-fold incision can easily be substituted.  相似文献   
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Adenylyl-(5'leads to N)-amino acids containing as amino components, methyl esters of D-, L- and DL-phenylalanine, D-, L- and DL-tyrosine, and D-, L- and DL-tryptophan have been investigated by proton magnetic resonance (PMR) spectroscopy and circular dichroism (CD). The temperature and pD dependences of proton chemical shifts of these compounds have been studied. These data, together with the magnitudes of the upfield chemical shifts of the PMR signals of adenine and aromatic amino acids residues in adenylyl-(5'leads to N)-amino acids, have enabled us to construct conformational models of these compounds. The proposed conformation has been substantiated by the CD results. It is shown that in adenylyl-(5'leads to N)-amino acids the planes of adenine and amino acid aromatic moieties are roughly parallel. The aromatic rings of phenylalanine and tyrosine are localized approximately above the centre of adenine. In adenylyl-(5'leads to N)-D, -(L)-tryptophan, the six-membered rings of the indole overlaps the five-membraned ring of adenine indole partially overlaps the six-membered ring of adenine. A difference in the non-covalent interactions of D- and L-amino acids with nucleotides has been revealed. The mutual localization of the aromatic systems of AMP and the amino acids and also the positions of -OCH3 group with respect to the centre of the amino acid aromatic moiety differs in the series of the studied nucleotide derivatives of D- and L-amino acids.  相似文献   
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A calf into which a biolized, total artificial heart (TAH) had been implanted survived for 145 days. All measured physiological parameters except central venous pressure (CVP) were back to normal one month after implantation, and thereafter the animal's physiological development was similar to that of a normal calf. The intimal weight, which was 96 kilograms at implantation, reached 190 kilogram at the end of experiment, with a daily gain rate of 0.9 kilogram per day. After the nineteenth postoperative week, signs of congestive heart failure appeared, such as high venous pressure, ascites, and enlarged liver although the calf outwardly appeared well. On postoperative day 146, the animal started foaming at the mouth, and a convulsion occurred; then, the experiment was terminated after 3,494 hours of pumping. At autopsy, there were acute bilateral bronchopneumonia involving mostly both upper lobes, pulmonary edema, slight chronic pneumonitis, and hepatomegaly. There were no serious thrombotic deposits inside the cardiac prosthesis.  相似文献   
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