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OBJECTIVES: The purpose of this study was to determine quality of life (QOL) and exercise performance (EP) in patients with persistent atrial fibrillation (AF) converted to sinus rhythm (SR) compared with those remaining in or reverting to AF. BACKGROUND: Restoration of SR in patients with AF improving QOL and EP remains controversial. METHODS: Patients with persistent AF were randomized double-blind to amiodarone, sotalol, or placebo. Those not achieving SR at day 28 were cardioverted and classified into SR or AF groups at 8 weeks (n = 624) and 1 year (n = 556). The QOL (SF-36), symptom checklist (SCL), specific activity scale (SAS), AF severity scale (AFSS), and EP were assessed. RESULTS: Favorable changes were seen in SR patients at 8 weeks in physical functioning (p < 0.001), physical role limitations (p = 0.03), general health (p = 0.002), and vitality (p < 0.001), and at 1 year in general health (p = 0.007) and social functioning (p = 0.02). Changes in the scores for SCL severity (p = 0.01), functional capacity (p = 0.003), and AFSS symptom burden (p < 0.001) at 8 weeks and in SCL severity (p < 0.01) and AF symptom burden (p < 0.001) at 1 year showed significant improvements in SR versus AF. Symptomatic patients were more likely to have improvement. The EP in SR versus AF was greater from baseline to 8 weeks (p = 0.01) and to 1 year (p = 0.02). The EP correlated with physical functioning and functional capacity except in the AF group at 1 year. CONCLUSIONS: In patients with persistent AF, restoration and maintenance of SR was associated with improvements in QOL measures and EP. There was a strong correlation between QOL measures and EP.  相似文献   
13.
A double-blind randomised controlled trial of the effect of low dose lofepramine (70 mg once daily) against placebo was carried out on depressed elderly inpatients on general medical wards for the elderly, comparing measures of depression and side-effects between the randomised groups. Patients were identified for the study using the Geriatric Depression Scale (GDS) and the Brief Assessment Schedule Depression Cards (BASDEC). Sixty-three subjects were randomised: 46 patients completed the entire trial of 28 days treatment. BASDEC and GDS were administered on day 8 post-admission, and depressed patients were randomised double-blind to either low dose lofepramine (70 mg daily) (n = 23) or placebo (n = 23). Assessment of changes in depressive states were made using the Montgomery Asberg Depression Rating Scale (MADRS) on days 8, 18 and 36 post-admission. Both groups improved by a similar amount during the trial. Lofepramine tended to be more effective than placebo in those patients who were more depressed (GDS > or = 18). On the other hand, subjects who were less depressed (i.e. GDS < 18) improved more on placebo than lofepramine. Low dose lofepramine may prove useful in moderately or severely depressed patients treated for only 4 weeks. However, low dose lofepramine is not indicated for mild (GDS 15-18) depression.  相似文献   
14.
Phospholipase A2 (PLA2) activity enhances snake venom cardiotoxin (CTX)-induced and general anesthetic (halothane)-induced hemolysis of red blood cells. In the case of halothane-induced hemolysis, this effect appears to be related primarily to free fatty acids. In the present study, the interaction between CTXs and halothane and the effects of different free fatty acids on cardiotoxin and halothane-induced hemolysis were examined. The hemolytic actions of halothane and a CTX from Naja naja kaouthia venom were examined in erythrocytes with different phospholipid and free fatty acid composition from five species. The extent of hemolysis by CTX or halothane was dependent upon the species examined and appeared to be inversely related to the amount of saturated free fatty acid in the membrane. The order of susceptibility of red blood cells from five species to hemolysis was similar for halothane- and N. n. kaouthia CTX-induced hemolysis, but very different for osmotic fragility. The slope of the hemolysis dose-response curve was considerably steeper for halothane than for CTX. Hemolysis due to N. n. kaouthia CTX was greatly increased by halothane in erythrocytes from humans and horses and to a lesser extent in erythrocytes from sheep, goats and cows. Hemolysis induced by halothane and the N. n. kaouthia or Naja naja atra CTXs was enhanced by unsaturated fatty acids. In contrast, hemolysis induced by halothane was decreased and that caused by the two CTXs was relatively unaffected by saturated fatty acids. Halothane and CTXs differ in their exact mechanisms, but appear to act upon similar fatty acid-sensitive processes.  相似文献   
15.
We describe three patients with the American Indian type of polymorphous light eruption (actinic prurigo), two Cree Indian sisters and a Cree Indian boy, who had eye symptoms similar to those seen in limbal-type vernal catarrh.  相似文献   
16.
The retina contains specific high-affinity receptors for insulin-like growth factor-I (IGF-I). Although IGF-I binding was observed in photoreceptor outer segments, the level of this binding was only 10% of that found in whole retina or mixed preparations of rod outer (ROS) and inner (RIS) segments. The higher IGF-I binding activity in RIS and non-photoreceptor regions of the retina suggests these sites as candidates for putative IGF-I action. Data from crosslinking experiments with and without neuraminidase treatment indicate that the binding subunits of the retinal IGF-I receptor exist in two subpopulations (Mr = 121- and 131 kDa), and that the larger of the two subunits has either a greater number or more exposed sialic acid residues. In these characteristics, the retinal IGF-I receptor is similar to the retinal insulin receptor. Retinal IGF-I and insulin receptors possess kinase activity towards their own beta-subunits, a tyrosine containing copolymer, and various molecular forms and subunits of transducin (T alpha-GDP, T alpha-GTP, T beta). The transducin forms are phosphorylated with different efficiencies (e.g. T alpha-GDP is 10-15 times more effective than T alpha-GTP as substrate). These differences are also observed in basal conditions and may reflect differences in transducin subunit affinity for the IGF-I and insulin receptor. In all retinal areas examined, tracer IGF-I binding is 10 to 20-fold higher than insulin binding; however, autophosphorylation levels are approximately equal.  相似文献   
17.
Preventing and treating pressure sores.   总被引:5,自引:3,他引:2       下载免费PDF全文
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18.
Changes in plasma insulin and glucose concentrations before and after feeding were measured in six female subjects (post-obese) who had regained a normal body mass after a history of severe obesity (mean weight loss, 37.1 +/- 2.6 kg). The responses of the post-obese group were compared with a group of weight- and age-matched subjects who had not been obese (lean). After an overnight fast subjects were fed a meal at 09.00 h and 13.10 h. Fasting and post-prandial insulin concentrations were lower in post-obese than in lean subjects. Immediately after beginning to eat at 13.10 h all subjects showed a rise in insulin concentration with no change in glucose concentration. In this pre-absorptive period there was no significant difference in insulin concentration between post-obese and lean subjects, although the increment in insulin concentration over baseline values was greater in post-obese subjects (P less than 0.05). It is concluded that abnormalities of insulin secretion and action remain after weight loss by obese subjects. These abnormalities may predispose to hyperphagia and accumulation of excess adiposity.  相似文献   
19.
Background: Smoking is considered to be a risk factor for patients undergoing surgery and anesthesia, but it is unclear whether this is applicable to patients undergoing ambulatory surgery. The aim of this study was to determine the risk of respiratory complications and wound infection among smokers.

Methods: The authors studied a random selection of 489 adult patients undergoing ambulatory surgery. Smoking status was determined by self-report and confirmed with end-expired carbon monoxide analysis. The risk of respiratory complications (i.e., desaturation, cough, laryngospasm, bronchospasm, breath-holding, or apnea) and wound infection (i.e., wound redness or discharge +/- positive microbial culture, requiring antibiotic therapy) in smokers versus nonsmokers was ascertained. Odds ratios were estimated from multivariable logistic regression and adjusted for age, gender, body mass index, partner's smoking status, domiciliary smoking exposure, and extent and duration of surgery.

Results: Most smokers continued to smoke up until the day of surgery. Smokers had a higher rate of respiratory complications (32.8%vs. 25.9%; adjusted odds ratio, 1.71; 95% confidence interval, 1.03-2.84;P = 0.038) and wound infection (3.6%vs. 0.6%; odds ratio, 16.3; 95% confidence interval, 1.58-175;P = 0.019). Odds ratios comparing current plus ex-smokers with nonsmokers were of similar magnitude for most of these complications.  相似文献   

20.
OBJECTIVE: To determine factors influencing rationing decisions in a surgical ICU during a temporary nursing shortage when two to six of the unit's 16 beds were closed. DESIGN: Blinded, concurrent data collection, retrospective chart review. SETTING: Surgical ICU. PATIENTS: All patients (n = 308) for whom a surgical ICU bed was requested were studied during a 3-month period. MEASUREMENTS AND MAIN RESULTS: Admitting patterns did not change and no attempts were made to limit admissions to more severely ill patients during times of the greatest shortage of surgical ICU beds. Contrary to findings in previous reports, the severity of illness of patients admitted to the surgical ICU decreased as bed availability and bed census decreased. Bed allocation across surgical services was influenced by factors other than medical suitability. Of major users, cardiothoracic surgery experienced the highest percentage (59%) of all patient admissions and lowest percentage (1.6%) of all denied admissions. General surgery experienced the lowest percentage (15%) of all admissions and highest percentage (10.4%) of all denied admissions, although these patients had the highest average Acute Physiology and Chronic Health Evaluation (APACHE II) scores for all patients admitted (17.7) and for patients denied admission (15.8). CONCLUSIONS: Surgical attending physicians rarely used other open inhouse ICU beds when surgical ICU beds were unavailable. Political power, medical provincialism, and income maximization overrode medical suitability in the provision of critical care services.  相似文献   
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