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71.
ABSTRACT The efficacy and safety of propafenone, 150 mg four times daily, were compared with those of disopyramide, 100 mg four times daily, in a randomized single-blind, cross-over study in 38 patients with symptomatic premature ventricular complexes (PVCs). The 24-hour ambulatory ECG, employed for assessing antiarrhythmic efficacy, was analyzed blindly. The median reduction in the number of PVCs was higher with propafenone than with disopyramide (91.4% vs. 63.5%, respectively, p<0.01). A reduction of at least 80% was achieved by propafenone in 22 (59%) and by disopyramide in 16 patients (43%) (NS). Ventricular tachycardias (VTs) were abolished by propafenone in eight out of 11, and by disopyramide in five out of nine patients with VTs (NS) A possible proarrhythmic effect was seen in three patients during disopyramide and in one patient during propafenone treatment. Micturition disturbances (p<0.001) and a dry mouth (p<0.01) were more commonly associated with disopyramide than with propafenone. In conclusion, in the given dosages, propafenone was superior to disopyramide in suppressing PVCs and had fewer side-effects.  相似文献   
72.
Twenty-four patients about to undergo surgery for mitral stenosisor constxictive pericarditis were studied by recording intra-arterialblood pressure and heart rate continuously during the inductionperiod. In two groups of patients, narcosis was induced withthiopentone or hexobarbitone. In the third group, inductiontook place with nitrous oxide. The investigation shows that:(1) A significant increase in blood pressure occurred duringintubation in all three groups, and was most marked in the thiopentonegroup. The blood pressure returned to the initial values inthe thiopentone and nitrous oxide groups. Pronounced hypotensionappeared in the hexobarbitone group. (2) A significant increasein heart rate during intubation occurred only in the barbiturategroups. Bradycardia appeared in the hexobarbitone group. *Present addresses; Anaesthesia Department, East Hospital, Universityof Gothenburg, Sweden. Present addresses; Anaesthesia Department, County Hospital,Skellefteft, Sweden.  相似文献   
73.
Tryptophan (Trp) metabolism and disposition and excitatory andother amino acid concentrations were determined in alcohol-dependentsubjects in relation to the alcohol-withdrawal syndrome (AWS).Parameters were examined in 12 alcohol-dependent male subjects,undergoing elective upper digestive tract tumour resection,and 12 age-, gender-, and medication-matched controls on threeoccasions: pre-operatively, post-operatively, and immediatelybefore (i.e. within 24 h of) the appearance of the AWS. No significantdifferences were observed between controls and alcoholic subjectson the first or second of these occasions. On the third occasion,within 24 h of the appearance of the AWS, alcoholics showeda dramatic elevation (117%) in free serum Tip concentrationand a consequent increase (111%) in the ratio of [free Trp]/[competingamino acids], which is an accurate predictor of Trp entry intothe brain. Increases were also observed on this third occasionin concentrations of total Trp (49%), cortisol (123%), and norharman(137%). Concentrations of glutamate, glycine, aspartate, serine,and taurine did not differ significantly within or between thecontrol and alcohol-dependent groups of subjects on any of thethree occasions. The possible significance of the Trp and relatedmetabolic changes in relation to the behavioural features ofthe AWS is discussed.  相似文献   
74.
Abstract. In order to study the natural course of venous flow and temperature reaction in the legs after symptomatic first episode of deep vein thrombosis (DVT), 65 patients (57 with proximal DVT) without further thromboembolic complications during the observation period were followed for 1 year by repeated plethysmography (PG) and thermography (TG). Regarding the non-invasive parameters substantial individual variations were observed during the observation period. After 1 year pathologic PG and TG were still demonstrated in 39% (Iμ (95%) = /0.43±0.05/) and 65% (Iμ (95%) = /1.18±0.11/), respectively, of the patients after proximal DVT. Only a minority of the patients were normalized permanently in both PG and TG during the first year. The high frequency of remaining venous obstruction and especially, persistent thermoactivity is notable and may be of clinical importance.  相似文献   
75.
abstract — Biopsies of homogeneous leukoplakias and non-involved oral mucosa were obtained from the same patient, and buccal mucosa samples were obtained from individuals free of oral mucous membrane disease. Activities of glucose-6-phosphate dehydrogenase (G6PDH), pyruvate kinase (PK), glycerol-3-phosphate dehydrogenase (G3PDH), NAD and NADP dependent isocitrate dehydrogenases (ICDH) were quantitated in microdissected specimens of the superficial third of the epithelium. ICDH (NAD) was measured photo-kinetically with the aid of a bioluminescent system. The remaining enzymes were assayed according to the techniques developed by l owry and co-workers. The activities of G6PDH and G3PDH in non-involved mucosa of leukoplakia patients were double those of mucosa from healthy controls. The activities of PK and ICDH (NAD and NADP) in these two groups of lesion-free mucosa were similar. Non-involved mucosa differed from leukoplakias with respect to the two ICDH's. In hyperorthokeratinized leukoplakias, NAD and NADP dependent ICDH activities were decreased by 59% and 37%, respectively. The values for the two ICDH's in hyperparakeratinized lesions lay between the levels of activity in noninvolved mucosa and hyperorthokeratotic leukoplakias but did not differ significantly from either.  相似文献   
76.
ABSTRACT Two patients, 15 and 20 years old, were admitted after an overdose of theophylline in a slow-release preparation. The gradual occurrence of clinical symptoms reflected the slow gastrointestinal absorption of the drug, and therefore active treatment was not started until 10 and 12 hours after intake, respectively. Peak s-concentrations were 275 and 1295 μmol/l, respectively. One patient was treated with hemoperfusion only, whereas the more severely intoxicated patient was treated with combined hemoperfusion and hemodialysis. Only about 0.2 g theophylline was eliminated by hemodialysis in this patient compared to a calculated amount of 6.9 g by hemoperfusion. Severely theophylline-intoxicated patients should be treated with supportive therapy and hemoperfusion.  相似文献   
77.
78.
abstract — Odontoblasts isolated from rat incisors were incubated in vitro in the presence of tritiated leucine or fucose, and the amount of precursor incorporated into TCA-precipitated proteins was determined. The effect on precursor incorporation of varying the total precursor concentration was examined. The incorporation of leucine and fucose into TCA-precipitated proteins was found to be linear with time for at least 90 min. Inhibition studies with puromycin, cycloheximide and chloramphenicol demonstrated the presence of odontoblastic protein synthesis. One hour after in vivo administration of tritiated leucine the highest specific activity of odontoblast-predentin protein material was noted the corresponding maximum for pulp proteins was found to occur after 30 min. The in vivo incorporation of tritiated fucose was maximal after 4 h in both odontoblasts and pulp tissue.  相似文献   
79.
ABSTRACT: Samuelson, G., Blomquist, H. K:son, Crossner, C.-G., Holm, A.-K. and Grahnén, H. (Departments of Paediatrics and Pedodontics, University of Umeå, Umeå, Sweden). An epidemiological study of child health and nutrition in a northern Swedish county. VII. A comparative study of general and dental health, food habits and socioeconomic conditions in 4-year-old children. Acta Paediatr Scand, 64:241, 1975.–A study of the general and dental health and the food habits of randomly selected 4-year-old Swedish urban children was performed. The results were compared with the findings of an investigation carried out four years earlier in the same area. In comparison with the earlier study no significant differences were found in haemoglobin values, packed red cell volume, microsedimentation rate and anthropometric measurements. The food habits had altered. A reduction in the frequency of between-meal consumption, particularly of sweets and soft drinks, as well as a reduction of the frequency of meat, fish and egg consumption was found. The children had an increased sandwich and milk consumption. The caries frequency was markedly reduced, which might be explained by the decreased between-meal consumption and an increased consumption of fluoride tablets. The food habits and the caries situation were generally influenced by the parents' socio-economic conditions, especially their educational level.  相似文献   
80.
Abstract – The dissolution of two analytical calcium fluoride preparations was studied in aqueous solution. Dissolved calcium fluoride was determined from analysis Ca and F in solution. Original samples of the two preparations and the residue after partial dissolution were studied by X-ray diffractometry in comparison with natural fluorite. The dissolution of calcium fluoride was found to be extremely slow. After a period of 1–15 weeks, depending on the experimental conditions, a state was reached where apparently no further dissolution occurred, although the solution was far from saturation. The dissolution rate was obviously closely related to the crystal size. On partial dissolution the mean crystal size increased, probably due to the disappearance of the finest fractions. Placing the salt in a dialysis bag before immersion in the water lowered the dissolution rate and increased the undissolved fraction considerably. The results seem to support the assertion that calcium fluoride accumulated in early carious lesions after topical applications of fluoride may persist for considerable periods of time.  相似文献   
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