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HORTON, R.P., et.al .: Diagnosis of ICD Lead Failure Using Continuous Event Marker Recording . Stored electrograms enhance the ability to evaluate therapy episodes in the third-generation implantable cardioverter defibrillator. These electrograms are recorded from either the shocking or rate sensing leads, but not both. As a result, differentiation of certain types of sensing abnormalities may be difficult prior to surgical exploration. We present a case of rate sensing lead failure due to an insulation break. Several minutes of recording of the event marker in the laboratory failed to document any abnormal sensing; the diagnosis was made by recording the event marker on a 24-hour continuous (Holter) monitor. The Holter monitor/event marker combination was of substantial diagnostic value and allowed for a more focused surgical evaluation and treatment.  相似文献   
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2-Mercaptopyridine was used to effect the selective, mild and efficient cleavage of the o-nitrophenylsulphenyl amino-protecting group from several amino acids and peptides. By utilization of this reagent a stepwise synthesis of the tetrapeptide Thr-Lys-Leu-Arg([Leu3]tuftsin) was successfully achieved. The potential use of 2-mercaptopyridine in mechanized peptide synthesis via the polymeric reagents approach is discussed.  相似文献   
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Abstract: :We report two patients with inferior myocardial infarction, complicated by bradyarrhythmia, hypotension, and clinical evidence of right ventricular infarction. Conventional therapy of volume expansion and inotropic support was insufficient to maintain an adequate blood pressure. Sequential atrioventricular (AV) pacing for AV block (Case 1) or atrial pacing for junctional bradycardia (Case 2) resulted in immediate and sustained improvement in blood pressure and clinical indices of perfusion. We recommend consideration of these pacing modes in patients with inferior infarction with evidence of right ventricular infarction, bradyarrhythmia, and cardiogenic shock. The likely mechanism of improvement is by restoration of atrial transport with consequent improvement in ventricular function.  相似文献   
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Summary. In 92 Hindu Asians, 59% of them vegetarian, and 51 Europeans longitudinal measurements were made during pregnancy of the zinc and copper concentrations in plasma and hair together with urinary zinc excretion, as indices of their zinc and copper status. Maternal diets were assessed once at booking. Zinc intakes ranged from 3·1 to 16·9 mg/day, with average intakes least in vegetarian Hindus and most in Europeans. Average copper intakes ranged between 1·48 and 1·80 mg/day and were similar in the three patient groups. Both ethnic groups showed the pregnancy-associated fall in the plasma concentration of zinc and rise in that of copper but throughout the study Hindus had statistically significant lower levels of zinc and higher levels of copper than Europeans. Urinary zinc excretion was not only significantly lower throughout the study in Hindus than in Europeans but the increase in excretion which occurred after 20 weeks gestation was smaller. There were no ethnic differences in the zinc content of hair. Urinary zinc excretion correlated with both plasma zinc levels and dietary zinc. Mean birth-weight in the Hindus was 2912 g and 34% of infants were below the 10th centile, using the Aberdeen standards, compared with 6% of the European babies (mean birthweight 3349 g). No association was found between crude or adjusted birthweight and any of the measures of zinc or copper status in either ethnic group. The Hindus had an apparently lower average zinc status than the Europeans, but there was no evidence that this had acted as a nutritional constraint and was the cause of their slower rate of intrauterine growth.  相似文献   
307.
Operant conditioning offers a new therapeutic modality for fecal incontinence. Our experience with biofeedback therapy in six male and six female patients (ages 12–78 years) is presented. Incontinence was associated with a surgical procedure in six patients and with a medical condition in six patients. Rectosphincteric manometry was performed using a three balloon technic. with one balloon positioned in the rectum as a distending stimulus and the others at the internal and external sphincters. Pressure responses to measured volumes of rectal distention were displayed on a polygraph. Rectosphincteric reflexes and sensory thresholds for rectal distention were determined. Patients were then encouraged to elevate sphincter pressures while observing their manometric responses. Follow-up of 10–96 weeks showed ten patients had good responses, with complete continence in six patients. Nine of 10 responders required only one treatment session. Operant conditioning is a valuable technic in properly selected patients with an 80% probability of success.  相似文献   
308.
A 28-year-old, 16 week primigravida presented with an acute anteroseptal myocardial infarction and a past history of recurrent venous thromboembolism and primary infertility. Although she lacked other clinical features of systemic lupus erythematosus, she had a circulating lupus' anticoagulant, anticardiolipin antibodies, a weakly positive anti-nuclear antibody and thrombocytopenia. She died suddenly despite corticosteroid therapy and autopsy revealed coronary arteritis and thrombosis.  相似文献   
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Gastrointestinal bleeding in aortic stenosis is an uncommon condition but when present it is often undiagnosed. The usual radiological proceedures fail to demonstrate the source of bleeding. Mesenteric angiography, however, will identify the lesion. The lesion is usually a vascular malformation located in the right colon. The angiodysplasia may also occur in other parts of the gastrointestinal tract. We have encountered five patients with aortic stenosis who had multiple massive hemorrhages of the lower gastrointestinal tract who defied diagnosis by the conventional methods. Mesenteric angiography, however, disclosed the orgin of the bleeding. In four patients vascular malformations were found in the right colon and one in the jejunum. Right hemicolectomy and partial jejunectomy resulted in a cure in all.  相似文献   
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