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991.
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We investigated diagnostic testing in polyarteritis nodosa (PAN) by calculating, from published data, the sensitivity and specificity of visceral angiography and muscle, nerve, testicle, kidney, and liver biopsy. Test sequence strategies were constructed by Bayesian inference using a computer program written for this purpose. Test sequences were compared with an aggressive strategy consisting of repeated tests until there was a positive finding or until the available tests were exhausted, and a conservative strategy consisting of 1 biopsy procedure plus angiography. The Bayesian analysis agreed most closely with the conservative approach for most prior probabilities (degree of suspicion) that a patient had PAN. The aggressive strategy had an overall sensitivity of 90% and specificity of 91%, whereas the conservative strategy was 85% sensitive and 96% specific. Furthermore, the aggressive strategy was more costly ($2,986 versus $1,961) and had a higher rate of morbidity (3.8 versus 2.7 days of hospitalization per patient evaluated) than did the conservative strategy. The mortality rates of both strategies were equivalent (∼0.05 deaths per hundred patients evaluated). The per-case cost of diagnosis increased as prevalence decreased, and at 10% prevalence, the aggressive strategy cost more than $17,000 per case diagnosed. Sensitivity analysis revealed that the strategies were moderately affected by the test characteristics, within reasonable assumptions, but that the differences in conservative and aggressive approaches remained. Thus, our analysis based on available data and the assumption of test independence suggests that the preferred diagnostic evaluation of patients with symptoms suggestive of PAN consists, in most cases, of a single biopsy procedure, with angiographic evaluation if necessary.  相似文献   
994.
995.
Long permanent remissions in malignant hematopoietic disorders can often be achieved by autologous bone marrow transplantation (ABMT) or by allogenic bone marrow transplantation (BMT). Previous studies have shown that such therapies may induce osteoporosis due to iatrogenic ovarian failure. The administration of hormone replacement therapy (HRT) in these women could prevent the adverse effects of long-term ovarian failure without remarkable side effects. The aim of this study was to evaluate how the bone mass is affected by HRT in patients undergoing ABMT or BMT adjusting the results for age, weight, and height. Subjects and methods: Thirteen women with previous ABMT/BMT were treated with a standard dose (0.625 mg/day) of conjugated equine estrogen (CEE) or with 50 μg/day of 17-β-estradiol in transdermal therapeutic systems (TTS) plus 5 mg/day of medroxyprogesterone acetate sequentially added to the last 12 days of estrogen therapy. Bone mass was measured prior to and 12 months following HRT. Blood samples were collected before therapy and during the 6th and 12th treatment months. Results: The mean time elapsed between bone transplantation and HRT initiation was 13.0 months (range 3–26 months). Before treatment nine patients were osteopenic and after HRT bone mass increased in all cases. Following ABMT/BMT, hepatic hyperenzymemia was detected in three patients. After 6 and 12 months of treatment no significant changes were observed in hepatic enzymes. Conclusion: Although hepatic hyperenzymemia is commonly considered as a contraindication for HRT, our results suggest that HRT is safe for these patients and that such therapy should be initiated after transplantation in women to prevent adverse effects of long-term ovarian failure.  相似文献   
996.
The purpose of this investigation was to document the clinical presentation of emergency department (ED) patients who tested positive for concurrent cocaine (COC) and ethanol (EtOH) use and the incidence of cocaethylene (CE) formation in this study population. Four study groups were evaluated: (1) drug-free, (2) EtOH-only, (3) COC-only, and (4) COC plus EtOH. CE was detected in plasma or urine specimens in 88% of the COC/EtOH-positive patients, and correlated directly with plasma COC and its metabolite benzoylecognine. Blood pressure and body temperature did not vary across study groups. COC/EtOH-positive patients displayed a significantly higher mean respiratory rate while the EtOH-only study group had an elevated mean heart rate. No significant differences were detected with respect to cardiac and neurological complaints between study groups. Trauma complaints in the drug-positive groups were more frequent than the incidence reported in the drug-free population. COC/EtOH-positive patients had the greatest percentage of trauma complaints (34.6%). Nearly half of the patients who tested positive for CE cited trauma as the primary reason for reporting to the ED. We conclude that ED patients who have concurrently used COC and EtOH are more closely associated with presentations related to traumatic injury than to those related to toxicologic complications.  相似文献   
997.
Jones type fifth metatarsal fractures pose a challenge to the foot and ankle surgeon, given documented high nonunion rates as well as high complication rates including hardware prominence, nerve injury, and screw breakage for existing treatment modalities including screw and plantar plate fixation. We call for the design of innovative Jones-fracture specific implants which contour to the natural curve of the fifth metatarsal. Future research should aim to expand upon existing literature for Jones fracture fixation and evaluate efficacy of novel implants which are designed to address unacceptably high complication rates for existing treatment modalities.  相似文献   
998.
S J Friedman  B J Fox  H L Albert 《Urology》1987,29(2):204-206
A case is reported of a forty-nine-year-old black man in whom numerous skin-colored papules and verrucoid plaques had developed on his penis over the course of fifteen years. He did not seek medical attention, and some of the lesions had become quite large. The initial clinical impression was condyloma acuminatum, and prior to therapeutic intervention histologic evaluation revealed findings diagnostic of seborrheic keratosis. Seborrheic keratoses should be considered in the differential diagnosis of penile lesions especially because of clinical similarities to condylomata acuminata.  相似文献   
999.
The purpose of this paper is to describe the intraoperative management of a type IIIb endoleak after deployment of a bifurcated endograft in a patient with narrow iliac access vessels. A 62-year-old man underwent elective endovascular repair (EVAR) of a 53 mm abdominal aortic aneurysm. After device deployment, a large IIIb endoleak, arising from the main body of the device, was visualized. Narrow iliac vessels precluded deployment of a second bifurcated graft, and the endoleak was successfully excluded with an aortomonoiliac device, followed by contralateral iliac occlusion and subsequent creation of a femorofemoral bypass. At 1-year follow-up, the aneurysm remains excluded and is decreasing in size. Type III endoleaks are a known complication of EVAR, requiring immediate treatment through their association with aneurysm enlargement and rupture. If an additional bifurcated graft cannot be used, aortomonoiliac conversion represents a feasible endovascular alternative treatment for type III endoleaks, other than conversion to open surgical repair. Therefore, aortomonoiliac converters with appropriate occluder devices should be readily available during deployment of bifurcated devices.  相似文献   
1000.
Thoracic endovascular aortic repair (TEVAR) has decreased the morbidity and mortality associated with open surgical repair of descending thoracic aortic diseases, but important complications unique to the procedure remain. Spinal cord ischemia and infarction is a recognized complication caused by endovascular coverage or injury to spinal cord collateral vessels. Stroke is a consequence of thromboembolism or coverage of aortic arch branch vessels with insufficient collateral circulation. Understanding the risk factors and the pathophysiology of neurological complications of TEVAR are important for the successful anesthetic and surgical management and treatment of patients undergoing endovascular procedures involving the thoracic aorta.  相似文献   
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