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991.
Extremely high radio frequency power densities exist in the vicinity of modern microwave transmitting equipment and constitute a hazard to personnel and material. This paper discusses the problem and describes a new simple means of measuring and indicating the presence of hazardous microwave radiation. The equipment described utilizes a unique integrating component to accumulate the total radiation received from hazardous RF sources during a fixed sampling period. In this manner it correctly measures the damaging dosage received from RF sources which often produce widely time varying fields due to pulsing and antenna scanning.  相似文献   
992.
The basis for the radioimmunoassay of parathormone (PTH) as a routine method is a new sheep antiserum and a labelled PTH stabilised by a modification of the purification technique. The antiserum is obtained by immunisation with pig and cattle parathormone, it is C-terminal specific and is used in the assay in a final dilution of 1:35000. The affinity to human PTH is markedly greater than of the antisera used up to now. Two purification steps of 125J labelled bovine PTH lead to a tracer with a nonspecific binding of approximately 5% which increases to approximately 10% within 6 weeks. All normal sera investigated so far were measurable quantitatively (normal range 0.7 to 2.5 mul/equiv.). The lower sensitivity range was at 0.3 mul/equiv. All patients with chronic renal insufficiency and dialysis patients have an increased PTH concentration (3.9 to greater than 20 mul/equiv.). This also applies to patients with primary hyperparathyroidism (2.9 to greater than 20 mul/equiv.).  相似文献   
993.
Clinical and morphologic observations are described in a 46 year old woman with fatal trichinosis. Attention is called to the occurrence of extensive ventricular endocardial damage with superimposed thrombosis; Evidence is presented to indicate that the most likely cause of the endocardial damage is the associated eosinophilia. The mechanism by which eosinophils damage endocardium, however, remains obscure.  相似文献   
994.
Elevated circulating levels of immunoreactive parathyroid hormone (PTH), hypercalciuria and renal calculi were found in 3 patients with distal renal tubular acidosis (RTA). Treatment with alkali resulted in a fall of PTH toward normal and a reduction in urinary calcium, but the frequency of urolithiasis was unchanged. In one patient in whom prolonged follow-up was possible, a subtotal parathyroidectomy was performed. This was followed by virtual cessation of stone formation despite persistence of the acidification defect. This study suggests that RTA may be associated with secondary hyperparathyroidism and that the consequent elevation in PTH may play a contributory role in the pathogenesis of renal calculi.  相似文献   
995.
996.
997.
The therapeutic approach to vascular lesions, which in fact represents the effective prevention of potential or recurrent brain damage, is discussed. The following problems are considered: asymptomatic localized vascular bruit; transient ischemic attack; minor strokes; progressive strokes; total strokes; and hemorrhages. Supportive therapy in the patient with brain damage is presented.  相似文献   
998.
A new, specific haemolytic assay for C2 is described using EAC43 (Antrypol) cells and serum deficient in C4 and C2 from a patient with hereditary angio-oedema. The method is simple and the results in pathological and normal sera correlate well with those obtained using the EA and C2-deficient serum method.  相似文献   
999.
1000.
Carbamazepine (CA)-induced antidiuresis and fluorescence in urinary cortisol assay was compared during short-term and prolonged treatment in 3 patients with pituitary diabetes insipidus. The fluorescence induced by excreted CA-metabolite(s) (probably CA-10-11 epoxide and its derivatives) was used for the rough clinical estimation of the rate of metabolic elimination of the drug. A marked decrease was observed both in the antidiuretic response induced by CA and excretion of CA metabolite(s) during prolonged treatment - with a fixed dose of CA. These findings suggest that diminishing antidiuretic effectiveness might be due to auto-induction of CA. Auto-induction of CA may explain the delay in improvement of renal concentrating operation in patients with DI during long-term treatment with fixed doses of CA. Another clinical consequence of this mechanism may be the prevention of the development of water intoxication in neuro-psychiatric patients undergoing chronic treatment with CA.  相似文献   
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