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81.
Cardiac arrhythmias are a well known cause of mortality for patients with heart disease. However, sinus tachycardia is a more unusual arrhythmia which can lead to serious heart damage or death. Even young patients with structurally normal hearts may become gravely ill.

This case study outlines the condition of sinus tachycardia, and associated changes in heart function, altered cellular structure of the myocardium and compensatory mechanisms in the body. Treatment modalities, including electro-physiological studies and drug therapies to moderate the tachycardia and myocardial oxygen demand of the heart, are discussed. Fourteen year old ‘Ben’ was previously a well, active and outgoing youth who suddenly became critically ill. He endured weeks of hospitalisation, numerous serious complications including Torsade de pointes arrhythmia, Cheyne-Stokes respirations, nausea and dizziness during this acute phase. Despite challenges, Ben's severely compromised heart muscle recovered at a remarkable rate.  相似文献   

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Gall bladder hydatid cyst is a rare entity. Concurrent occurrence of gall blader hydatid cysts along with liver cysts, especially with the biliary channels clear of cysts, is very rare. We report a 27-year-old man with a gall bladder hydatid cyst that was diagnosed only after opening the resected specimen of the gall bladder.  相似文献   
85.
In an attempt to tap underlying competencies, the ability of children with autism to comprehend pretend acts carried out by an experimenter was compared with that shown by controls. These acts consisted of the pouring of a pretend substance from an appropriate container onto a target figure. There was no significant difference in the groups' ability to identify the pretend substance involved, to predict the pretend outcome of the actions, or to reflect on the pretend nature of the episodes. However, the performance of controls on these latter two tasks was surprisingly poor, limiting the implications that might be drawn from the observed absence of group differences in comprehension abilities.We are very grateful to the teachers and headteachers of the following schools for their cooperation and assistance throughout the period of this research: John Worrall School, Sheffield; Doucecroft School, Kelvedon; East Hill First and Middle School, Sheffield; East Hill Second School, Sheffield; Mossbrook School, Sheffield; Priory School, Doncaster; The Rowan School, Dore; St. Mary's School, Sheffield. We also thank James Russell for his helpful comments of earlier drafts of this paper.  相似文献   
86.
Previous clinical use of the Rotablator(TM) In coronary artery disease has involved a sequential increase in burr sizes up to 2 mm in diameter and has often utilized balloon adjunct to achieve an optimal result. We report our experience and describe our technique using a single, large burr (2.25, 2.5, or 2.75 mm diameter) without balloon assistance. The burr size was selected to approximate 70–90 percent of the apparent normal lumen diameter. Thirty-one patients with 36 lesions of complex morphology (eccentric, irregular, calcified, ulcerated, at bends, at bifurcations, completely occluded, as well as balloon failures) were successfully treated with the Rotablator(TM). Results were assessed by computerized quantitative angiography. The percent diameter stenosis (mean ± SD) for the group was reduced from 69.8 ± 11.3% to 30.9 ± 10% (p < 0.001). The mean absolute diameter stenosis increased from 0.9 ± 0.3 mm to 2.2 ± 0.3 mm (p < 0.001). Angiographically visible dissections were seen in 4 patients and were uncomplicated in 2. One patient had a non-Q-wave myocardial infarction. A fourth patient had a presumed acute occlusion 36 hr after the procedure, necessitating emergency bypass surgery, but without Q waves on the electrocardiogram or wall-motion abnormalities on the echocar-diogram. Nitroglycerin was infused through the Rotablator(TM) catheter and has considerably lowered the degree and frequency of spasm. No other acute complications occurred. The mean procedure time using a single burr was shorter than when multiple burrs were used: 56.5 vs. 97.3 min, respectively (p < 0.05). The use of a single, large-size Rotablator(TM) burr is an effective method of treating complex coronary stenoses without balloon assistance and has an encouragingly low complication rate and short procedure time. © 1992 Wiley-Liss, Inc.  相似文献   
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Vinylogous hydroxamic acids (3-(N-hydroxy-N-alkylamino)-2-propen-1-ones, VHA) were prepared as antiinflammatory agents. The synthesis, chemical properties, and in vitro biological activities of these relatively unexplored compounds are described. The VHAs were prepared by condensation of the appropriate N-substituted hydroxylamine with any of the three reagents: a 1,3-dicarbonyl compound (method A); a vinylogous amide (method B); or an alkynone (method C). The VHAs exist as one or more tautomers in solution with the relative proportions of each being dependent upon the structure of the VHA, solvent, and pH. VHAs undergo some of the typical reactions of hydroxamic acids as well as those of vinylogous amides. VHAs are active as inhibitors of 5-lipoxygenase and of IL-1 biosynthesis in vitro, which do not inhibit other enzymes of the arachidonic acid cascade. They have been shown by ESR studies to bring about inhibition of soybean type 1 15-lipoxygenase by reduction of the active site iron.  相似文献   
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CHIP (325 mg/M2), a second generation cisplatin derivative, was administered intravenously every 3 weeks to 85 pediatric patients with recurrent sarcomas (19), osteosarcomas (20), neuroblastoma (23), germ cell tumors (10), and other malignant tumors (7). Thirty-eight of them had been previously exposed to cisplatin. Partial remissions were only observed in 3 of 23 (13% SE=7%) patients having neuroblastoma. Severe thrombocytopenia (65%) and neutropenia (35%) were the dose limiting factors.  相似文献   
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