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71.
A 47-y-o man had been suffering from cardiac failure due to refractory ventricular tachycardia (VT) after myocardial infarction. He underwent resection of the left ventricular aneurysm and cryocoagulation of the arrhythmogenic foci. On the 2nd post-operative day, VT often recurred in spite of repeated cardioversion and drug therapy, and threatened his life, even under IABP. Therefore, a veno-arterial bypass route was made and extracorporeal lung and heart assist, ECLHA, was started with a heparin bonded Maxima lung on the following day. Even under ECLHA, VT continued to recur. Cryocoagulation of the VT foci was tried again, without immediate success. A record high dose of beta-blockers, given under the circulatory support by ECLHA, stopped VT on the following day. The patient was weaned from the ECLHA circuit 12 days after the first operation, then from IABP on the 14th day. During the 10 day course of surgeries and ECLHA, the patient had almost 100 defibrillations. But for ECLHA, we may say that the patient couldn't have survived two open heart surgeries, administration of a great amount of beta-blockers, and repeated cardiac arrest without neurological sequelae.  相似文献   
72.
Acute abdomen     
Acute surgical abdomen is the object of urgent surgical attention. The objective of emergency operation is to interrupt a process that has a steadily worsening prognosis on a scale of hours unless effective surgical treatment is rendered. There are basically three processes to address: free or incipient sepsis and peritonitis, gastrointestinal soilage, and hemorrhage.  相似文献   
73.
A double blind placebo controlled study was carried out in 40 subjects newly referred for treatment for obesity to determine the effects of the new thermogenic beta adrenoceptor agonist BRL 26830A. The subjects were randomised to receive either BRL 26830A, 200 mg daily for two weeks then 400 mg daily, or placebo for 18 weeks, and all were instructed to follow a 3.35 MJ diet that was low in fat and high in fibre. Weight loss was 15.4 (SD 6.6) kg in subjects given BRL 26830A compared with 10.0 (5.9) kg in those given placebo (p = 0.02). The relative weight loss was 0.93 (0.39%) a week with BRL 26830A and 0.61 (0.38)% with placebo (p = 0.02). Urinary excretion of nitrogen was similar in both groups, whereas measurements of skinfold thickness indicated a 4.1 kg difference in the amount of fat lost, suggesting that weight loss with BRL 26830A was mainly from adipose and not lean tissue. BRL 26830A had no effect on resting pulse rate or pressor effects on either diastolic or systolic blood pressure. No significant differences were found between the two groups in serum cholesterol concentration, percentage of high density lipoprotein cholesterol, plasma concentrations of glucose and insulin, the ratio of glucose to insulin, serum concentrations of triiodothyronine and thyroxine, and creatinine clearance. Short term administration of BRL 26830A to six subjects who had taken the drug for 18 weeks showed that the expenditure of energy increased by 11.6% during the second hour after administration, which suggests that BRL 26830A may enhance weight loss thermogenically. BRL 26830A may be a useful drug in the treatment of obesity.  相似文献   
74.
Two amphiphilic peptides from hymenopterid insects, melittin and mastoparan, stimulate secretion in a variety of cell types. In PC12 cells, both peptides stimulate calcium influx with melittin some 20-fold more potently than mastoparan. Melittin stimulates both breakdown of phosphoinositides (Pl) by phospholipase C to yield inositol phosphates and hydrolysis of phospholipids by phospholipase A2 to release arachidonic acid (AA). Mastoparan stimulates Pl breakdown, but has no effect on AA release. Maximal stimulation of Pl breakdown occurs at 1 to 2.5 micrograms/ml melittin and 30 micrograms/ml mastoparan, whereas maximal stimulation of AA release occurs at 2 to 5 micrograms/ml melittin. Organic calcium channel blockers (nifedipine, verapamil, diltiazem) have little or no effect on responses to the peptides. The influx of calcium elicited by melittin or mastoparan is completely or nearly completely blocked by inorganic calcium channel blockers (Co++, Mn++, Cd++). Mn++ and Cd++ inhibit melittin-induced Pl breakdown and AA release and mastoparan-induced Pl breakdown. Co++ has no effect on melittin-induced Pl breakdown and potentiates mastoparan-induced Pl breakdown. Pertussis toxin has no effect on the Pl breakdown induced by either peptide. The responses to melittin and mastoparan in PC12 cells are compared to those reported for maitotoxin.  相似文献   
75.
A case of mycotic aneurysm of the intracavernous carotid artery is reported and the literature is reviewed on this uncommon entity. Nineteen cases have been reported, most often occurring in the clinical setting of meningitis. Management recommendations include angiographic confirmation of aneurysm and follow-up with magnetic resonance imaging during antibiotic therapy. Evidence of aneurysm enlargement is an indication for endovascular trapping of the aneurysm or carotid occlusion.  相似文献   
76.
OBJECTIVE: Patients on L-thyroxine with a 'suppressed' TSH (< 0.05 mU/l) were compared to those in whom TSH was detectable but not elevated (0.05-4.0 mU/l), with regard to morbidity data. DESIGN: Biochemical data from Tayside Thyroid Register was matched to hospital admissions data obtained from Health Board Statistics. PATIENTS: The patients were identified from those registered on the computerized Tayside Register. MEASUREMENTS: Serum T4 and TSH assays, clinical assessment scores, and admission records with regard to ischaemic heart disease, overall fractures, fractured neck of femur and breast carcinoma. RESULTS: Over one year, 1180 patients on thyroxine replacement had clinical and biochemical assessment; 59% had a suppressed TSH and 38% 'normal' TSH. Patients with a suppressed TSH exhibited higher median serum thyroxine levels (146 nmol/l, range 77-252 vs 119 nmol/l, 58-224; P < 0.001). Patients under the age of 65 years on L-thyroxine had an increased risk of ischaemic heart disease compared to the general population (female 2.7 vs 0.7%, P < 0.001; male 6.4 vs 1.7%, P < 0.01), but the risk was no different between those with suppressed and normal TSH. There was no increase in risk for overall fracture, fractured neck of femur or breast carcinoma in those on thyroxine with suppressed or normal TSH. CONCLUSION: Patients under the age of 65 years on L-thyroxine had an increased risk of ischaemic heart disease. There was no excess of fractures in patients on L-thyroxine even if the TSH is suppressed.  相似文献   
77.
78.
While there is growing awareness for the need to examine the etiology of problem behaviors across cultural, racial, socioeconomic, and gender groups, much research tends to assume that constructs are equivalent and that the measures developed within one group equally assess constructs across groups. The meaning of constructs, however, may differ across groups or, if similar in meaning, measures developed for a given construct in one particular group may not be assessing the same construct or may not be assessing the construct in the same manner in other groups. The aims of this paper were to demonstrate a process of testing several forms of equivalence including conceptual, functional, item, and scalar using different methods. Data were from the Cross-Cultural Families Project, a study examining factors that promote the healthy development and adjustment of children among immigrant Cambodian and Vietnamese families. The process described in this paper can be implemented in other prevention studies interested in diverse groups. Demonstrating equivalence of constructs and measures prior to group comparisons is necessary in order to lend support of our interpretation of issues such as ethnic group differences and similarities.  相似文献   
79.
80.
In contrast to other types of congenital heart defects, the treatment of hypoplastic left heart syndrome (HLHS) has become comparably successful only within the last decade. Postnatal management of circulatory disturbances of HLHS was previously often performed, similarly to other types of neonatal shock, without considering the peculiarities of postnatal hemodynamics. It is of overwhelming importance to limit pulmonary hyperperfusion by reducing systemic afterload and avoiding artificial respiration. The invention of selective hypothermic cerebral perfusion using the modified Blalock-Taussig shunt has decreased the need for long circulatory arrest times involving the brain, and promises a better neurological outcome. Postoperatively, sophisticated hemodynamic monitoring is mandatory to provide sufficient systemic oxygen delivery. α-blockers are usually given for strong afterload reduction. Hospital mortality is as low as 10–15% in centers experienced with the Norwood operation. The next surgical steps to create a serial systemic and pulmonary circulation involve superior cavopulmonary anastomosis performed as early as possible (4–6 months) and finally total cavopulmonary connection at an age of 3–4 years.  相似文献   
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