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991.
992.
To explore if change in the extent of emphysema correlated with change in lung function, the effect of resection of emphysematous tissue was studied by computed tomography (CT) densitometry. In addition, the current authors studied how surgery-induced change in emphysema related to lung density in control subjects. In total, 30 patients (14 females; mean+/-sd age 59+/-10 yrs) with severe emphysema before and 3 months after lung volume reduction surgery (LVRS), 48 patients with moderate emphysema and 76 control subjects were investigated. Lung density (15th percentile point) of both lungs and heterogeneity of lung density between 12 isovolumetric partitions in each lung were calculated from chest CT images. The 15th percentile point and its heterogeneity could distinguish controls from subjects with moderate emphysema with a sensitivity and specificity of >95%. LVRS significantly increased lung density by 5.0+/-10.9 g.L(-1) (n=30). Improvement in the diffusing capacity of the lung for carbon monoxide and in residual volume significantly correlated with an increase in lung density (n=20 and 28, respectively). Change in forced expiratory volume in one second did not correlate with change in lung density. In conclusion, lung density 15th percentile point is a valuable surrogate marker for detection of both the extent of and reduction in emphysema.  相似文献   
993.
994.
Coronary artery fistula is often considered to be a benign and rare congenital anomaly. It is usually an incidental finding encountered during routine cardiac catheterization. We report a case of a patient presenting with endocarditis involving a large coronary artery fistula connecting an aneurysmal circumflex coronary artery to the coronary sinus. The diagnosis was initially made by echocardiography and confirmed by cardiac catheterization. In addition, we briefly discuss the literature on management of this coronary anomaly.  相似文献   
995.
PURPOSE: To describe and discuss the status of patient safety in U.S. hospitals. METHODS: Personal interview. This report is part of a series of discussions with a leading expert on patient safety. FINDINGS AND CONCLUSIONS: Some improvements have been made in the past 10 years. But changes have not been adequate. Continuing barriers include the punitive environment in hospitals, physicians' denial of the scope of the problem, lack of national leadership, and lack of systems thinking.  相似文献   
996.
BACKGROUND: The effective dose for treating glabellar lines with botulinum toxin type A in men has not been studied adequately. OBJECTIVE: To compare the safety, efficacy, and duration of response of four doses of botulinum toxin type A on glabellar rhytids in men. METHODS: Eighty men were randomized to receive a total dose of either 20, 40, 60, or 80 U of botulinum toxin type A (BOTOX, BOTOX Cosmetic, or Vistabel, Allergan, Inc., Irvine, CA, USA) in the glabellar area. Glabellar lines were assessed at rest and maximum frown by a trained observer at baseline, 2 and 4 weeks, and monthly thereafter. Patients provided self-evaluations at the same visits. Adverse events were monitored throughout. RESULTS: The 40, 60, and 80 U doses of botulinum toxin type A were consistently more effective in reducing glabellar lines than the 20 U dose (duration, peak response rate, improvement from baseline). There was a dose-dependent increase in both the response rate at maximum frown and the duration of effect assessed by the trained observer. In addition, the participants reported a dose-dependent reduction in the ability to frown, improvement in their global assessment, and increased feelings of attractiveness, self-confidence, and satisfaction. The incidence of adverse events was not increased with higher doses. CONCLUSION: Male participants with glabellar rhytids benefit from starting doses of at least 40 U of botulinum toxin type A.  相似文献   
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Actin cytoskeletal polymerization is associated with a pro-proliferative, pro-survival state. We hypothesized that the actin polymerization of wound cells is increased in the presence of wound matrix attachment and is decreased after disruption of this attachment. Musculocutaneous flap and wound splinting models were used to investigate the effect of wound matrix attachment on the actin cytoskeleton. Disruption of wound matrix attachment was accomplished by incision of the wound matrix/dermis interface (wound matrix release) and/or desplinting. Polymerized actin was assayed with phalloidin labeling of wound specimens 24 hours after disruption of attachment and a method to quantify the content and organization of polymerized actin in granulation tissue was used. Disruption of wound matrix attachment decreased the content of polymerized actin, the actin staining intensity, and the actin fiber organization in the granulation tissue of both the flap and splint models. Disruption of wound matrix attachment decreased actin polymerization and fiber organization in the granulation tissue. Our data support the concept that the state of wound matrix attachment regulates the actin cytoskeleton of wound cells.  相似文献   
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