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The present study examines the reproducibility and validity of computerized muscle strength and endurance evaluation protocols using the Ariel Computerized Exercise System (ACE). Since the ACE has only recently become commercially available, there are no published normative data for various exercises, nor are the measurements' accuracy and validity for the various exercise protocols documented. Twenty males (17 to 30 years old) performed a set of isokinetic maximal leg and arm exercises on the ACE Multi Function Unit twice on 2 separate days. Test-retest correlation coefficient ranged from 0.44 (bench press) to 0.91 (bench pull and leg extension flexion). Thirty additional male subjects (16 to 31 years old) performed, on 2 separate days, the Wingate Anaerobic Test (WAnT) (leg), and various force and endurance leg exercises (squat) on the ACE. Correlation coefficients of the various performance indices between the 2 test systems ranged from -0.02 to 0.23. The results obtained on the ACE indicate moderate to high reproducibility and low concurrent validity with WAnT.  相似文献   
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C J Swallow  S Grinstein  R A Sudsbury  O D Rotstein 《Surgery》1990,108(2):363-8; discussion 368-9
Within the acidic milieu of an abscess or tumor, macrophages must be able to maintain their cytoplasmic pH (pHi) close to the physiologic range to ensure optimal cell function. Our recent studies have demonstrated that a proton-extrusion mechanism with the characteristics of an H+ adenosine triphosphatase mediates pHi recovery in acid-loaded macrophages. These studies were designed to examine the role of these H+ pumps in maintaining cell function in an acidic extracellular environment. Peritoneal macrophages were tested for superoxide production in response to phorbol myristate acetate at either physiologic or acidic extracellular pH (pHo; 7.35 or 6.70, respectively). pHi was measured with the fluorescent dye 2',7'-biscarboxy-ethyl-5(6)-carboxy-fluorescein. Bafilomycin A1, a specific H+ adenosine triphosphatase inhibitor, was used to examine the contribution of the H+ pump to pHi regulation and cell function. At pHo 7.35, bafilomycin A1 had no effect on pHi or phorbol myristate acetate-stimulated superoxide production. However, at pHo 6.70, bafilomycin A1 reduced pHi to 6.61 +/- 0.01 versus 6.79 +/- 0.01 in control cells (p less than 0.001) and caused a concomitant reduction in superoxide production to 4.8 +/- 1.2 versus 13.0 +/- 1.2 nmol/10(6) cells/40 min in control cells (p less than 0.001). To determine whether the observed reduction in superoxide formation was the result of the pHi reduction, superoxide production was measured in cells whose pHi was pharmacologically clamped at various levels according to the K+/nigericin method. Lowering pHi from 6.80 to 6.60 caused a significant reduction in superoxide production from 13.1 +/- 1.8 to 7.5 +/- 0.9 nmol/10(6) cells/40 min (p less than 0.01). Thus H+ extrusion pumps are important to maintenance of macrophage pHi at low pHo, permitting continued superoxide production under these conditions. By keeping pHi close to the physiologic range, these pumps serve to optimize cell function in an acidic extracellular environment.  相似文献   
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Cancer survival in Estonian migrants to Sweden.   总被引:2,自引:0,他引:2       下载免费PDF全文
OBJECTIVE: To quantify the eventual extra loss of life incurred to cancer patients in Estonia compared with those in Sweden that was possibly attributable to differences in society. DESIGN: Population based survival of cancer patients in Estonia was compared with that of Estonian immigrants to Sweden and that of all cancer patients in Sweden. The cancer sites studied were female breast and ovary, male lung and prostate, and male and female stomach and colon. SETTING: Data on incident cases of cancer were obtained from the population based Swedish and Estonian cancer registries. PARTICIPANTS: Data from Estonian patients in Sweden, Estonian patients in Estonia, and patients from the total Swedish population were included in the study. MAIN RESULTS: Differences in survival among the three populations, controlling for follow-up time and age at diagnosis, were observed in breast, colon, lung, ovarian, and prostate cancers. The survival rates of Estonians living in Sweden and the total population of Sweden were better than that of the Estonians living in Estonia. For cancers of the breast and prostate, the excess mortality in the older age group (75 and above) was much greater in Estonia than in the other populations. CONCLUSIONS: Most differences in cancer survival between Estonian and Swedish populations studied could be attributed to a longer delay in diagnosis, and also to inferior treatment (including access to treatment) in Estonia compared with Sweden. Estonia's lag in socioeconomic development, particularly in its public health organisation and funding, is probably the main source of the differences observed.  相似文献   
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A randomized trial was conducted to compare the efficacy and safety of fluconazole versus that of amphotericin B in the treatment of candidemia in non-neutropenic adults. Enrollment was stratified by disease severity (APACHE II score). Patients were randomized (1:1) to receive amphotericin B 0.6 mg/kg/day (cumulative dose 8 mg/kg) or fluconazole 800 mg intravenous loading dose, then 400 mg daily for four weeks (intravenous for at least 10 days). Patients were monitored for six months. A total of 106 patients were enrolled. A protocol amendment implemented midway through the trial required patients to be removed from the study and treated with amphotericin B if species identification indicated candidemia due toCandida glabrata orCandida krusei. Baseline characteristics were similar for the two groups; 103 patients (fluconazole, 50; amphotericin B, 53) met the major enrollment criteria. The intention-to-treat analysis indicated successful therapy in 50% of fluconazole recipients compared to 58% of the amphotericin B group (p=0.39; one-sided 95% Cl, –8 to 24%). The efficacy analysis included 84 patients (fluconazole, 42; amphotericin B, 42); successful outcomes were observed in 57% and 62% of cases in the fluconazole and amphotericin B groups, respectively (p=0.66: one-sided 95% Cl, –12 to 22%). The mortality at day 14 for the fluconazole group was 26% and for the amphotericin B group 21% (p=0.52; chi-square test) and remained similar throughout the course of follow-up. Drug-related adverse events were more frequent with amphotericin B than with fluconazole and prompted switching of therapy for two (4%) and zero cases, respectively. Fluconazole and amphotericin B were associated with similar clinical response rates and survival in the treatment of candidemia among non-neutropenic patients; however, drug-related adverse events were more frequent with amphotericin B.  相似文献   
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This article represents an attempt to clarify questions posed by evidence of varying pathways to change in social anxiety. A new perspective is developed which addresses these questions and, importantly, lays the foundation for an innovative treatment approach. Essentially, social anxiety is construed here as the product of a disorganization in which feelings and cognitions (both conscious and preconscious) about the self, about other people, and about the relations between self and others are organized. Specifically, the socially anxious client experiences others autocentrically: that is, in terms of how the other person perceives, evaluates and affects one's own self. The result is a narrowed capacity for experiencing others. The goal of treatment in the new approach advocated here is to allow the individual to understand, appreciate and share the feelings, thoughts and experience of other people. Therapy is directed toward getting clients out of themselves and into other people.  相似文献   
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The charts of 25 patients who died in the intensive care unit of persistent peritonitis after abdominal operations were reviewed to determine the microbial flora and the efficacy of antibiotic treatment. All patients had undergone two or more surgical procedures for abdominal sepsis and 23 had at least three-system organ failure. The most common organisms cultured were: Staphylococcus epidermidis, 24 cultures from 16 patients, Candida albicans, 19 cultures from 10 patients, Pseudomonas aeruginosa, 16 cultures from 12 patients, Enterobacter, 16 cultures from 8 patients and enterococcus, 14 cultures from 8 patients. The classic isolates, Escherichia coli (11 cultures from six patients) and Bacteroides fragilis (4 cultures from three patients) were found infrequently. To determine the adequacy of antimicrobial therapy for this "new" flora, we examined the ability of appropriate agents to eradicate the micro-organism upon subsequent culture. Candida sp. were eradicated in 54% (6 of 11) of the assessable cases, while enterococcus and S. epidermidis were cleared in only 25% and 28% respectively. The spectrum of intra-abdominal organisms cultured from critically ill surgical patients in the intensive care unit differs from that seen in those with acute peritonitis. Despite administration of appropriate antimicrobial agents, these organisms tend to persist, probably reflecting impaired host defences with multiple-system organ failure rather than antimicrobial failure.  相似文献   
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