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91.
We report a case of a 69-yr-old previously healthy man with acute spontaneous Achilles tendon rupture and severe tendonitis, which occurred after 2 weeks of steroid therapy for newly diagnosed giant cell arteritis. The Achilles tendon rupture was treated conservatively and the tendonitis resolved incrementally with steroid dose reduction. The patient made a complete recovery. In view of the widespread use of steroids in practice, this novel case presentation has important clinical implications. The tendon rupture early in the course of high-dose steroid therapy expands the understanding of this adverse reaction, which was previously reported only with long-term steroid therapy. The severe tendonitis responded to steroid therapy reduction suggesting a dose correlation. This report adds to a sole previous report of a spontaneous Achilles tendon rupture associated with giant cell arteritis. 相似文献
92.
Building a better quality measure: are some patients with 'poor quality' actually getting good care?
Kerr EA Smith DM Hogan MM Hofer TP Krein SL Bermann M Hayward RA 《Medical care》2003,41(10):1173-1182
BACKGROUND: National performance measures monitor the proportion of diabetic patients with low-density lipoprotein (LDL) levels >/=130 mg/dL, but such simple intermediate outcomes measure poor control, not necessarily poor care. "Tightly linked" quality measures define good quality either by a good intermediate outcome (LDL <130 mg/dL) or by evidence of appropriate responses to poor control (eg, starting or optimizing medications for high LDL or not doing so in the face of contraindications). OBJECTIVES: We examined hyperlipidemia therapy for patients with diabetes to determine the relative accuracy of quality assessment using simple intermediate outcome versus tightly linked quality measures. RESEARCH DESIGN: Retrospective longitudinal cohort. SUBJECTS: A total of 1154 diabetic patients with an LDL test done between October 1, 1998, and March 31, 1999, in 2 large VA facilities. MEASURES: LDL levels, medication treatment, and explanations for poor quality. RESULTS: Although 27% (307 of 1154) of patients had an LDL >/=130 mg/dL using the simple intermediate outcome measure, only 13% (148 of 1154) were classified as having substandard quality using the tightly linked measure. Among the 159 reclassified to adequate quality, 117 had lipid-lowering medication started or increased within 6 months of an LDL >/=130 mg/dL, 8 were already on high-dose medication, 12 had a repeat LDL <130 mg/dL, and 22 had contraindications to treatment. CONCLUSION: Simple intermediate outcome measures can be an inaccurate reflection of true quality of care, and many patients classified as having substandard quality by "poor control" might actually be receiving good quality of care. 相似文献
93.
Direct conversion detectors offer the potential for very high resolution and high quantum efficiency for x-ray imaging, however, variations in signal can arise due to incomplete charge collection. A charge transport model was developed to describe the signal and noise resulting from incomplete charge collection. This signal to noise ratio (SNR) reduction was incorporated into the cascaded systems model for a simple x-ray detector. A new excess noise factor, A(c) (termed the collection noise factor) is introduced to describe the reduction in detective quantum efficiency (DQE). The DQE is proportional to the product of the quantum efficiency and the collection noise factor. If the trapping cross sections for electrons and holes are very different, and if the detector is biased improperly, the collection noise factor can drop to as low as 50%. In addition, the signal loss due to incomplete charge collection will reduce the DQE in the presence of added noise. Because of this, the DQE generally does not continue to improve with greater detector thickness. The collection noise factor and DQE are predicted for CdZnTe, PbI2, and Se. The optimization of detector thickness should be based not only on quantum efficiency but also on the charge collection statistics, which are influenced by bias field and polarity. 相似文献
94.
Environmental policy with regard to noise abatement has traditionally only considered whether the noise levels in a given setting are high enough to be deemed a source of annoyance, disturbance, or threat to well being. However, laboratory studies using both simple and more complex work-related tasks have shown that task-irrelevant sound, regardless of its intensity, intrudes upon cognitive processing and disrupts performance substantially; furthermore, its damaging effect does not diminish with repeated exposure to the sound over time. For tasks that require short-term memory processing (particularly the short-term maintenance of order information) sound assumes disruptive power if it is acoustically varying over its time course. However, other properties of sound (e.g., the semanticity of speech) can incur an additional cost if the primary task necessitates or tends to evoke the extraction of meaning. It will be argued that interference in each case is explained by reference to a conflict between two concurrent mental processes; that being demanded by the task and that being involuntarily applied to properties of the sound. Such harmful effects, as well as having direct consequences for the general well-being of those working in noisy environments, may have far reaching consequences for health insofar as extraneous sound is a feature of many safety-critical work settings. Implications for noise abatement policy are highlighted. 相似文献
95.
John F. Tarlton PhD a; Allen J. Bailey PhD a; Elsa Crawford BSc a; Dylan Jones MSc b; Keith Moore PhD b; Keith D. Harding MD b 《Wound repair and regeneration》1999,7(5):347-355
A 25 patient study was conducted into the relationship between markers of collagen metabolism in venous ulcer exudates and healing status, and their prognostic value in predicting healing performance. Wounds were sampled on at least 5 occasions over 12 months, the frequencies of which were determined by the need for clinic attendance. Specimens were taken from several sites on each ulcer using sterile preweighed filters. Wound margins were traced and sites recorded for each collection. Sample sites were evaluated for severity as improving, static, or deteriorating according to subsequent wound progression. Specimens were analyzed for levels of proenzyme and active forms of matrix metalloproteinases 2 and 9, neutrophil elastase, and type I collagen C propeptide. There was an overall trend of greater expression of all markers with increasing severity of wound site, this being highly significant for pro-matrix metalloproteinase-9 (p = 0.006). For samples collected simultaneously from improving and deteriorating regions of the same wound, paired data analysis showed statistically significant differences for pro-matrix metalloproteinase-9 (p < 0.001), neutrophil elastase (p < 0.005) and activated matrix metalloproteinase-9 (p < 0.05). Taken overall, these data show the potential of markers of collagen biochemistry as predictors of repair in venous ulcers; in particular pro-matrix metalloproteinase-9 and neutrophil elastase were found to be accurate prognostic indicators of subsequent healing. 相似文献
96.
97.
Susan L Murphy Dylan M Smith Neil B Alexander 《The American journal of occupational therapy》2008,62(3):329-334
OBJECTIVE: We examined how women with osteoarthritis naturally use activity pacing and how pacing relates to symptoms and physical activity within daily routines. METHOD: Thirty women with knee or hip osteoarthritis (mean age = 63.8 +/- 6.9) wore an actigraph accelerometer and repeatedly reported activity pacing, pain, and fatigue. Using the median split, symptom patterns were compared for low and high pacers. The relationship between activity pacing and physical activity was also examined. RESULTS: Activity pacing was low (1.4 +/- 0.9); pain and fatigue were mild (1.0 +/- 0.7 and 1.1 +/- 0.7, respectively). When compared with low pacers, high pacers had more severe, escalating symptoms. Activity pacing was related to lower physical activity (beta = -28.14, SE = 6.24), t(586) = -4.51, p = .0001. CONCLUSION. Pain, fatigue, and activity pacing use varied depending on average activity pacing level. High pacers may benefit from interventions to manage daily symptoms. 相似文献
98.
Jonathan J Hooper Shaun D James Dylan C Jones Dean M Lee Julianna M Gl 《Journal of Science and Medicine in Sport》2008,11(2):209-213
The purpose of this study was to investigate the influence of training with heavy rugby balls on selected spin pass variables in youth rugby union players. Pre-training, 14 participants performed rapid spin passes (using right and left hands) at a wall-mounted target, from 7-m and 10-m distances. Horizontal (linear) and spin (longitudinal angular) velocities of the passes were recorded using a 25Hz video camera. Participants also performed right- and left-handed spin passes for maximal distance. The participants were then randomly divided into two equal groups, to train twice weekly for eight weeks, using either normal or heavy rugby balls. Each individual performed 50-90 rapid spin passes ranging from 5m to 12m with each hand per session. Following training, participants were reassessed using the same pre-training protocols. Significant changes were found pre-to-post training for both the normal ball, and heavy ball groups, for 7-m right-handed horizontal (linear) velocities (9.80+/-0.45 to 10.27+/-0.82ms(-1), and 9.42+/-1.04 to 10.19+/-1.03ms(-1), respectively; p=0.029), 10-m left-handed spin (longitudinal angular) velocities (5.13+/-1.60 to 6.08+/-1.30revss(-1), and 4.39+/-1.62 to 5.81+/-0.65revss(-1), respectively; p=0.014), right-handed maximal distance passes (19.0+/-3.6 to 20.6+/-4.0m, and 18.6+/-3.4 to 20.7+/-4.3m, respectively; p=0.001) and left-handed maximal distance passes (15.3+/-3.2 to 18.1+/-2.5m, and 15.0+/-3.0 to 17.6+/-3.7m, respectively; p<0.000). No significant changes could be attributed to training exclusively with the heavy rugby balls. The results of this investigation suggest that intense repetitive passing practice increases a small number of selected spin passing variables in youth rugby union players. 相似文献
99.
100.