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We report the case of a 4-year-old child with an atypical presentation of an aspirated unwitnessed foreign body in the airway. During an attempt to obtain a biopsy of what appeared to be a mucosal growth, the foreign body was removed. This may be the first report of foreign body removal in a child this young, using a flexible fiberoptic bronchoscope. Pediatr Pulmonol. 1994; 18:51–52. © 1994 Wiley-Liss. Inc. 相似文献
3.
Eigenstructure assignment using output feedback is reformulated using an auxiliary principle of minimization of control effort. In the general eigenstructure assignment procedure, the feedback gain matrix is uniquely determined for a set of explicitly specified desired eigenvalues and eigenvectors. However, for the controller design proposed in this paper, only the most necessary constraints are imposed on the desired eigenvalues and eigenvectors, and the unspecified model parameters of the closed-loop system are determined by minimizing the control effort. Numerical examples are presented for comparison of the proposed method with standard eigenstructure assignment methods, and an experimental example gives an insight into the feasibility of the proposed control algorithm with application to the vibration control of flexible structures undergoing forced vibration. 相似文献
4.
William H. Isbister 《ANZ journal of surgery》1995,65(1):44-47
Total colonoscopy is arguably the best method available for examination of the colon and rectum. Colonoscopy costs are high and rising and it may be that in the future practitioners will be unable to afford to colonoscope all of the patients presently being examined. This retrospective study was undertaken in an attempt to examine the cost, in terms of lesions missed, of a limited endoscopy programme. During a 15 year period, 1426 colonoscopies were performed at Wellington Hospital, New Zealand. Total colonoscopy was possible in 79% of all patients. Three perforations occurred. Nine patients bled and two required blood transfusion after biopsy or ‘snaring’ of polyps. After exclusion of patients with continuous inflammatory bowel disease (IBD) 75% of all lesions were found in or distal to the descending colon. More cancers were found in patients colonoscoped because of bleeding. Thirty-two of 93 cancers diagnosed were proximal to the descending colon but 18 presented with bleeding. A further seven had a radiological abnormality. Only 7.5% of colorectal cancers would be missed by flexible sigmoidoscopy (65 cm) and 758 of the costs of total colonoscopy would be avoided if only patients presenting with bleeding and IBD were offered total colonoscopy and patients with radiological abnormalities were treated according to the abnormality. This compromise, based on the data presented, may represent a rational way to reduce colonoscopy costs. 相似文献
5.
JOHN H BOND 《Journal of gastroenterology and hepatology》1998,13(Z3):S252-S256
Abstract Colorectal cancer is the second most common cancer killer of Americans. Recently developed and tested methods of screening and surveillance can effectively diagnose and treat the disease in most patients before symptoms develop when the chance of cure is high. It is also possible to prevent colorectal cancer by detecting and resecting premalignant adenomatous polyps. Evidence-based guidelines recommend that the average-risk population greater than age 50 be screened with annual faecal occult blood tests plus periodic flexible sigmoidoscopy. This approach is feasible, efficacious, affordable and cost-effective in a high-risk country such as the US. Widespread compliance with these recommendations could reduce the mortality from this malignancy by more than 50%. 相似文献
6.
Unfried G Wieser F Albrecht A Kaider A Nagele F 《Human reproduction (Oxford, England)》2001,16(1):168-171
To evaluate patient acceptance, optical properties and the clinical feasibility of flexible compared with rigid hysteroscopes, 142 patients undergoing outpatient hysteroscopy were included in a prospective, randomized clinical trial. The flexible hysteroscope was used in 70 patients, and the rigid instrument in 72. At different stages of the hysteroscopy the level of pain experienced by the women was assessed using a 10 cm visual analogue scale. Optical properties characterized by the parameters intrauterine visibility, hysteroscopic view and diagnostic accuracy were ranked by the surgeons using a 5-point scale (1 = excellent to 5 = insufficient), and duration of the hysteroscopy was measured. Hysteroscopy was successful in 87.5 and 100% of patients in the flexible and rigid groups respectively. With the use of rigid telescopes, discomfort at introduction and during the hysteroscopy was significantly greater (median 1.7 versus 0.7, P = 0.003; 3.1 versus 1.2, P < 0.001 respectively), but optical properties were judged to be far superior (P < 0.001 for all three comparisons) and procedure time was significantly shorter (median 70 versus 120 s, P = 0.003). In conclusion, outpatient hysteroscopy seems to be less painful when using flexible telescopes. However, rigid hysteroscopes provide superior optical qualities and permit a more rapid performance with higher success rates at much lower cost. 相似文献
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双氯芬酸钠柔性脂质体的制备及其对离体小鼠皮肤的透皮效果 总被引:7,自引:1,他引:7
利用同离子效应制备双氯芬酸钠柔性脂质体,并考察脂质浓度对包封率的影响.同时比较了双氯芬酸钠乳膏、传统脂质体与柔性脂质体对离体小鼠皮肤的透皮效果.结果表明,同离子效应可显著增大柔性脂质体的包封率,较理想的脂质浓度为卵磷脂-胆酸钠为6∶1.2(g,w/w),离体小鼠皮肤12h累积透过率依次为:柔性脂质体>>传统脂质体>乳膏. 相似文献
9.
Christopher R. Gilbert Andrew Lerner Michael Baram Bharat K. Awsare 《Archivos de bronconeumologia》2013,49(5):189-195
IntroductionPulmonary infiltrates are common within the hematopoietic stem cell transplant (HSCT) population and unfortunately portend an increased mortality. Bronchoscopy is often utilized as an initial diagnostic tool, but the literature supporting its diagnostic utility and effect on clinical management varies significantly. The aim of this study was to investigate the diagnostic ability, complication rate, and clinical impact of flexible bronchoscopy (FB) in evaluating pulmonary infiltrates in a large HSCT population.Patients and methodRetrospective review of all patients undergoing FB after HSCT in the Bone Marrow Transplant Unit from 1996 to 2009.ResultsFB was performed 162 times in 144 patients with pulmonary infiltrates yielding positive results in 52.5%. The most common positive results were bacterial pneumonia (31%), fungal pneumonia (15%), and alveolar hemorrhage (11%). Treatment changes occurred in 44% of patients after FB. Treatment changes included antibiotic modification (59%), addition of corticosteroids (21%), antifungal modification (12%), and antiviral modification (7%). The overall complication rate associated with FB was 30%, although 84% of these complications were considered minor.ConclusionsFB in patients with pulmonary infiltrates after HSCT should still be considered a valuable tool in the evaluation and management of pulmonary infiltrates in the HSCT population. Future prospective, multicenter randomized studies are needed to evaluate the overall clinical impact that bronchoscopic results and management changes have in this unique population. 相似文献
10.
目的:探讨膀胱软镜在复杂性肾结石开放手术中的应用价值。方法:将膀胱软镜应用于复杂性肾结石开放手术中辅助结石取出及检查28例,术中经膀胱软镜探查,并配合钳夹冲洗肾盏切开等方法取出结石。结果:28例均获得成功,术后行B超及X片复查,仅2例结石残留。结论:肾多发结石开放手术中配合膀胱软镜检查可以提高手术成功率,减少结石残留率,减少对患者损伤,是一种安全有效的方法,同时还能对其他病变起到检查及治疗作用。 相似文献