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51.
Clinical trial data and fracture risk prediction models unequivocally demonstrate the utility of identifying prevalent vertebral fractures to predict future fractures of all types. Knowledge of prevalent vertebral fractures can alter patient management decisions and result in initiation of therapy to reduce fracture risk in some patients who would not otherwise be treated. Cost-benefit analysis demonstrates that identifying and treating patients with vertebral fractures, even those with a densitometric classification of osteopenia, is cost effective. Vertebral fractures can be readily identified in the office setting using standard radiography or Vertebral Fracture Assessment (VFA), a software addition to a central dual-energy X-ray absorptiometry (DXA) machine. In the United States, VFA was assigned a Current Procedural Terminology (CPT) code in January 2005. Nevertheless, coverage of VFA has not been uniformly embraced by Medicare carriers, companies that contract with the federal government to administer Medicare coverage and process claims for a region of the United States. Unlike DXA, for which uniform national coverage of qualified Medicare beneficiaries is mandated by the Balanced Budget Act of 1997, VFA coverage policies are determined by the local Medicare carriers. Third-party insurers are also variable in their coverage of VFA. This International Society for Clinical Densitometry (ISCD) White Paper documents the role of VFA in the evaluation and treatment of women with postmenopausal osteoporosis and compares it with standard spine radiography. Arguments used by some Medicare carriers and insurers to deny coverage of VFA in the United States are analyzed and critiqued. For health care providers within the United States, this White Paper may serve as a resource to respond to insurers who deny coverage of VFA. For health care providers regardless of their country, this article underscores the value of VFA as an alternative to spine radiography in the evaluation and management of postmenopausal women with suspected osteoporosis. 相似文献
52.
Coralline hydroxyapatite bone graft substitutes: preliminary report of radiographic evaluation 总被引:1,自引:0,他引:1
A new bone graft substitute made by conversion of the calcium carbonate exoskeleton of reef-building sea coral into hydroxyapatite has recently become clinically available. The normal radiographic appearance of two forms of this material is described. In the immediate postoperative period, the exoskeletal architecture of these implants is readily appreciated. With graft incorporation over the ensuing months, their intrinsic structure is gradually lost in association with poor marginal definition. Evolving radiographic findings reflect the biocompatible nature of these implants, which provides the potential for ingrowth of native bone with preservation of the coralline scaffold, resulting in enhanced biomechanical properties. 相似文献
53.
急性缺血性卒中影像学检查的建议——美国心脏协会的科学声明(中) 总被引:1,自引:0,他引:1
2.3核磁共振血管成像(MRA)
2.3.1背景和方法:在头部MRI检查中常结合MRA,用于急性卒中患者病情评估以指导治疗决策的制定^[19]。日前,有几种不同的MRA技术用于脑血管成像,包括二维时间飞跃(timeof-flight,TOF)序列、三维TOF序列、 相似文献
54.
Rokey R; Verani MS; Bolli R; Kuo LC; Ford JJ; Wendt RE; Schneiders NJ; Bryan RN; Roberts R 《Radiology》1986,158(3):771-774
The feasibility of using magnetic resonance (MR) imaging to estimate myocardial infarct size was explored in an in vitro model using only the inherent differences in contrast between infarcted and noninfarcted myocardium. Eight dogs underwent coronary occlusion; their hearts were removed 6 hours later. Estimates of T2 for normal and infarcted myocardium were derived from MR images. Infarct size was quantified anatomically using triphenyltetrazolium-chloride (TTC) staining and compared with MR estimates. The T2 values derived from the images clearly discriminated between infarcted (126 +/- 22 msec) and normal myocardium (88 +/- 10 msec, P less than .05), providing images with good contrast between normal and infarcted myocardium. Comparable differences in T2 values were also noted from spectrometric determinations. Estimates of infarct size by MR imaging compared well with TTC estimates (r = 0.98) over a wide range of infarct sizes from 3% to 29% of the left ventricular mass. These results suggest the potential for in vivo quantification of infarct size based on the inherent contrast difference between infarcted and normal myocardium. 相似文献
55.
急性失代偿性心力衰竭患者血清肌钙蛋白T水平检测的价值 总被引:1,自引:0,他引:1
目的:研究肌钙蛋白T的水平变化在急性失代偿性心力衰竭患者预后的价值。方法:选取急诊重症监护室收治的68例急性失代偿性心力衰竭患者,按照cTnT的水平分为cTnT阳性组(27例)和cTnT阴性组(41例)。观察两组患者室性期前收缩发生率、APACHEⅡ评分、在ICU入住时间、住院时间、住院病死率、随访出院后6个月内再入院率及6个月死亡率。结果:两组治疗期间利尿剂、扩血管药物使用、多巴胺和(或)多巴酚丁胺的使用和两组患者6个月随访期间死亡率比较差异无统计学意义(P〉0.05)。入院时APACHEⅡ评分、在ICU入住时间、住院时间、住院病死率及出院后6个月内再入院率比较均显示差异有统计学意义(P〈0.05)。结论:肌钙蛋白T水平是与治疗无关的危险因素之一。伴有肌钙蛋白T升高的急性失代偿性心力衰竭患者有较高的室性期前收缩发生率、较长的住院时间、短期预后差,监测cTnT水平对急性失代偿性心力衰竭患者的病情评估和短期预后有重要作用。 相似文献
56.
A case of recurrent hemoptysis following bronchial artery embolization is presented. The bleeding was successfully controlled by embolization of the thyrocervical trunk. 相似文献
57.
The effect of barium on blood in the gastrointestinal tract 总被引:2,自引:0,他引:2
58.
No EEG evidence of acute tolerance to desflurane in swine 总被引:1,自引:0,他引:1
Desflurane is a potent inhaled anesthetic associated with a dose-dependent depression of cortical electrical activity. Recently, it has been suggested that the burst suppression pattern seen in dogs given moderately high doses (2.0 MAC) of desflurane may spontaneously subside. This observation suggests the development of acute tolerance to at least some of the anesthetic effects of this drug. No other volatile anesthetic has been found to produce acute tolerance. We attempted to replicate these findings in domestic swine. Five juvenile swine (25-30 kg) were anesthetized with desflurane in oxygen and during normocapnia were exposed to two doses of desflurane sufficient to induce burst suppression (1.5 and 1.7 MAC) for 35 min at each dose, with a period of EEG recovery (0.6 MAC) before, between (in 3 of 5 animals), and after the high doses. Frontoparietal EEG was continuously recorded and the burst suppression ratio continuously calculated. Suppression was more complete at 1.7 MAC than at 1.5 MAC (98.24 +/- 1.75 vs. 90.80 +/- 3.05%, respectively, mean +/- standard deviation). The degree of burst suppression activity did not change over time at either 1.5 (P greater than 0.33) or 1.7 MAC desflurane (P greater than 0.41). There was no EEG evidence of tolerance to desflurane anesthesia in swine. 相似文献
59.
M. A. Listgarten S. Levin C. C. Schifter P. Sullivan C. I. Evian E. S. Rosenberg L. Laster 《Journal of clinical periodontology》1986,13(7):692-700
This report compares the clinical and microbiological status of 2 groups of subjects with treated periodontis on different maintenance schedules. 43 control (C) subjects were given prophylaxes every 3 months. 40 test (T) subjects were given this service on a flexible schedule according to the proportions of spirochetes and/or motile rods in fresh smears of subgingival scrapings. Both groups were examined every 6 months clinically and microbiologically. This report presents base line, 1- and 2-year data. Generally, mean values for both groups did not differ significantly from one another. Both groups exhibited comparable increases in GI and PLI scores during the first 2 years of this study. No change in probing depth was noted between base line and the 2-year examination. However, a slight increase in attachment level, as determined by probing, was noted in both groups. Both groups also exhibited similar proportions of bacterial morphotypes at base line and subsequent examinations. Disease recurrence, defined as an increase in probing depth of 3 mm or more from base line on any tooth surface during the 2-year period, tended to be more prevalent in the C than in the T group (15/43 C and 9/40 T subjects). However, the proportional difference between the groups was not statistically significant. Subjects with disease recurrence in the T group had greater proportions of spirochetes at base line than subjects in the same group without disease recurrence (20.2% versus 9.8%, p less than 0.01). This difference in proportions persisted if both groups were examined jointly, but was only of borderline significance (16.0% versus 10.5%, p = 0.05).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
60.
Decellularized dermis in combination with cultivated keratinocytes in a short- and long-term animal experimental investigation 总被引:4,自引:0,他引:4
H Bannasch† GB Stark† F Knam† RE Horch‡ M Föhn† 《Journal of the European Academy of Dermatology and Venereology》2008,22(1):41-49
Decellularized human dermis as a potentially ideal scaffold for dermal substitution in severe burns was examined in a two‐staged animal experiment. In an initial step, an in vitro generated composite graft consisting of human keratinocytes and decellularized dermis (AlloDerm®) was transplanted onto nude mice in a short‐term trial (n = 20, 14 days). Subsequently, a combined one‐step grafting of full thickness wounds with both decellularized dermis (in part preincubated with fibroblasts) and cultivated autologous keratinocytes as a cell suspension in fibrin glue was done in a long‐term porcine animal model (n = 10, 6 months). In both series, macroscopic wound healing was evaluated by planimetry. Histological investigations included morphological as well as immunohistochemical parameters. The short‐term study showed both successful integration of the composite grafts and reduction of wound contraction compared with the control group (epithelial grafts). The long‐term porcine study displayed reduced myofibroblast formation and contraction in the wounds that had been treated with fibroblast‐preincubated dermis. After 4 weeks, a decline of the structural integrity of the dermal matrix could be noticed. The utility of decellularized dermis as template for both dermal reconstitution and keratinocyte delivery vehicle was shown. The closure of full thickness wounds by a single‐step combination of an autologous keratinocyte fibrin sealant suspension and acellular dermis in a pig animal model could be shown. Incorporation of fibroblasts led to reduced wound contraction but could not prevent the loss of dermal integrity. The engineered ‘skin’ remained viable and stable over a period of 6 months. 相似文献