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In a double-blind, crossover study the effect of the potassium channel opener pinacidil (N'-cyano-N'4-pyridyl-N-1,2,2-trimethylpropylguanidine monohydrate) at 25 mg. per day was evaluated in 10 patients with detrusor instability and bladder outlet obstruction. Nine patients completed the study: in 7 pinacidil was without significant effect on urodynamic variables and in 2 detrusor instability was not found at the end of the pinacidil period. Maximum urinary flow, frequency and nocturia were unchanged during pinacidil treatment, compared to the initial test and the placebo period. There was a significant decrease in standing blood pressure but heart rate was stable throughout the study. No patient experienced distinct symptomatic improvement or side effects during pinacidil treatment. The results suggest that pinacidil at the dosage given is not effective for treatment of unstable detrusor contractions associated with bladder outflow obstruction.  相似文献   
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To test the hypothesis that the raised noradrenaline efflux rate constant in platelets observed in hypertensive individuals and some normotensive relatives to hypertensives could be ascribed to disturbances in the protein carboxyl methylation, protein carboxyl methylase activity and noradrenaline efflux rate constant were measured in platelets from 33 young healthy males. Sixteen had inheritance of hypertension. Protein methyl esterase activity and the noradrenaline efflux rate constant were measured in 43 men, 22 of whom had inheritance of hypertension. No correlation was found between unstimulated noradrenaline efflux from platelets and enzyme activity.  相似文献   
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Six painful hips in five patients were examined with magnetic resonance (MR) imaging and were found to have diffuse signal abnormalities in the marrow of the femoral head and neck, which extended into the intertrochanteric area in five cases. The abnormal regions were low in signal intensity on images obtained with a short repetition time (TR) and a short echo time (TE) and were isointense or hyperintense on long TR/TE images--findings that have been attributed by others to bone marrow edema. Edema was also seen in marrow just above the acetabulum in two cases. No focal abnormalities characteristic of osteonecrosis were seen. Osteonecrosis was subsequently shown to be present in all six femoral heads at core biopsy (three cases) or by subsequent development of focal MR abnormalities reported to be highly specific for osteonecrosis (three cases). The affected hips had been radiographically normal or subtly osteopenic and had shown intense radionuclide uptake in the femoral head at scintigraphy, with lesser abnormality in the neck and intertrochanteric region. Follow-up MR examinations of five of the six femoral heads showed the diffuse abnormalities to have been transient. Although diffuse MR abnormalities in the proximal femur are not specific, they may indicate the presence of osteonecrosis of the femoral head.  相似文献   
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In order to describe the British experience of Wegener's granuiomatosisHospital Activity Analysis was used to collect cases diagnosedin England, Wales and Scotland between 1975 and 1985. Wherepossible clinical details, histological material and chest radiographswere obtained. Two hundred and sixty five patients were consideredto have Wegener's granuiomatosis. In 109 a single pathologistconfirmed the diagnosis by finding both granulomas and vasculitisin biopsy material. The diagnosis was made on clinical groundsor clinical grounds together with histological diagnosis inthe local hospital in 156 patients. Wegener's granuiomatosiswas confined to the lung or upper respiratory tract in 22 percent of patients and renal disease occurred in 58 per cent.Laboratory tests showed a pattern of mild anaemia, polymorphleucocytosis, eosinophilia and an elevated ESR and hypergammaglobulinaemia,with no specific pattern of changes. Histological confirmation was most frequently obtained by examinationof nasal biopsy specimens, but multiple biopsies were oftenrequired. Renal biopsies showed focal proliferative glomerulonephritisbut granulomatous glomerulonephritis was uncommon. Of availablechest radiographs 61 per cent were abnormal, large opacitiesbeing most common. Small irregular opacities were found lessoften and other abnormalities were uncommon. Treatment varied widely and 10 per cent of patients receivedno drug therapy. This large series illustrates that even withoutspecific treatment, patients with Wegener's granuiomatosis cansurvive for several years and with modern treatment survivalfor more than a decade is possible. Conclusions about the effectivenessof the various therapies cannot be drawn from this restrospectivestudy. Renal failure and disseminated vasculities were the commonestcauses of death; death was considered to result from complicationsof treatment with cytotoxic drugs or prednisolone in 6 per centof patients.  相似文献   
77.
BACKGROUND: The Kell blood group system comprises 21 antigens residing on a red cell membrane glycoprotein of apparent M(r) 93,000. STUDY DESIGN AND METHODS: Serologic techniques were used to identify a new red cell antigen. The monoclonal antibody-specific immobilization of erythrocyte antigens (MAIEA) assay was used to identify the red cell membrane component carrying that antigen. RESULTS: A new high-frequency red cell antigen was identified and provisionally named RAZ. RAZ is absent from K.o red cells and from red cells treated with 2-amino- ethylisothiouronium bromide and is expressed weakly on McLeod phenotype cells. It differs from all other Kell system antigens, and no depression of other Kell system antigens on RAZ+ red cells was noticed. The RAZ antigen was shown by the MAIEA assay to be located on the Kell glycoprotein. CONCLUSION: RAZ is a new high-frequency antigen located on the Kell glycoprotein. The MAIEA assay is a very effective method of demonstrating the membrane structure carrying a red cell antigen.  相似文献   
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AIM: Antiplatelet therapy in order to reduce the platelet aggregability is widely used to prevent recurrent stroke events. Data from several studies indicates that the inter-individual variation concerning the ability of standard doses of aspirin to inhibit platelet aggregation is substantial. The rationale of the present study was to test whether platelet aggregation in whole blood was enhanced in subjects that had suffered an ischemic stroke event under aspirin treatment. METHODS: Two groups of patients were included: 1) patients that have suffered 1 stroke event and were thereafter under continuous treatment with aspirin 75-160 mg once daily (n=17); 2) patients that have suffered at least 2 stroke events, and aspirin 75-160 mg was prescribed after the 1(st) event (n=17). Platelet aggregation was tested in whole blood with collagen (5 microg/mL and 1 microg/mL), ADP (5 microMol/L) and arachidonic acid (0.5 microg/mL). Aggregation was recorded as change in impedance and release of ATP after the addition of a luciferin-luciferase reagent. RESULTS: The inhibitory effect of aspirin tested with arachidonic acid as an agonist was complete in all the tested subjects. Aggregation induced by ADP 5 microMol/L was significantly higher in the subjects with recurrent stroke compared to those with a single stroke, when tested as impedance change. ATP release with ADP as an agonist was the same in both groups. CONCLUSION: The present study gives some indication that differences in ADP-induced aggregation, with a higher remaining aggregating ability after ASA treatment, might be of importance for the risk of stroke recurrence.  相似文献   
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