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Background  

South African households are severely affected by human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) but health and economic impacts have not been quantified in controlled cohort studies.  相似文献   
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Six normal fasting males received on four separate occasions in random order (1) a placebo tablet followed 60 min later by 200 microgram of TRH intravenously (2) bromocriptine 2.5 mg orally followed by TRH intravenously (3) bromocriptine 2.5 mg orally followed by a placebo injection and (4) placebo tablet followed by placebo injection. Plasma prolactin and TSH responses to TRH were decreased following bromocriptine pretreatment. The rise of plasma growth hormone after bromocriptine was inhibited by TRH. The rise in plasma FSH seen after TRH injection was not influenced by bromocriptine pretreatment. Circulating LH and insulin concentrations were unaffected by any drug administration. These results suggest a dopaminergic influence on prolactin and TSH release in normal men, an inhibitory effect of TRH on bromocriptine stimulated growth hormone secretion, and no dopaminergic modulation of basal insulin secretion.  相似文献   
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Serum thymidine kinase (STK) levels have recently been used to detect tumour regression and progression in a number of hematological malignancies. In this study, patients with myeloma were monitored longitudinally for STK and several other potentially useful tumour markers to determine which laboratory parameters are the most useful for differentiating between stable and progressive disease. STK was determined by radioenzyme assay, lymphocyte surface markers were analysed by flowcytometry, plasma cell labelling index (LI) by immunofluorescence with anti BU-1, serum B2-microglobulin (SB2M) by radioimmunoassay and M proteins by radial immunodiffusion. Detailed multiparameter longitudinal investigations of 5 patients and ongoing studies of 70 other patients suggest that STK is a more reliable marker of progressive disease than either SB2M, LI, M-protein or CD10 positive lymphocytes. A rise in STK during the emergence of progressive disease at least paralleled and usually preceded any change in the other parameters which often did not change at all. All samples from patients with progressive disease (n = 29) had a STK above the normal range (0–5U/I) whereas 76% of patients in clear stable disease had a STK within the normal range. All samples (n = 34) from patients with light chain isotype suppression (LCIS) had STK values of less than 12 U/L and 82% of samples (n = 33) from patients without LCIS had a STK above the normal range (0–5U/L). The correlation between STK and LI was r = 0.65; p < 0.001 (n = 21). The radioenzyme assay for STK is simple, reproducible and a valuable tool for monitoring patients with myeloma and when used in conjunction with other clinical and laboratory investigations, aids in the separation of patients with stable myeloma from patients whose disease is progressive.  相似文献   
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Electromyographic studies of the onset of action of tubocurarine or alcuronium were performed on eight occasions in five patients who had liver masses. There was a slow onset of action and an increased dose requirement in those with malignant disease. Normal responses were found in a patient with benign nodular hyperplasia and in another where the malignant tumour was successfully treated with chemotherapy.  相似文献   
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