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BACKGROUND The adenoma detection rate(ADR) is inversely associated with the incidence of interval colorectal cancer and serves as a benchmark quality criterion during screening colonoscopy. However, adenoma miss rates reach up to 26% and studies have shown that a second inspection of the right colon in retroflected view(RFV) can increase ADR.AIM To assess whether inspection of the whole colon in RFV compared to standard forward view(SFV) can increase ADR.METHODS Patients presenting for screening or surveillance colonoscopy were invited to participate in this randomized controlled trial and randomized into two arms. In RFV arm colonoscopy was initially performed with SFV, followed by a second inspection of the whole colon in RFV. In the SFV arm first withdrawal was performed with SFV, followed by a second inspection of the whole colon again with SFV. Number, size and morphology of polyps found during first and second inspection in each colonic segment were recorded and all polyps were removed and sent for histopathology in separate containers.RESULTS Two hundred and five patients were randomly assigned to the RFV(n = 101) and SFV(n = 104) arm. In the RFV arm, both polyp detection rate(PDR) and ADR were increased under second inspection in RFV(PDR 1~(st) SFV: 39.8%, PDR 2~(nd)RFV: 46.6%; ADR 1~(st) SFV: 35.2%, ADR 2~(nd) RFV: 42%). Likewise, in the SFV arm,PDR and ADR were increased under second inspection(PDR 1~(st) SFV: 37.5%, PDR 2~(nd) SFV: 46.6%; ADR 1~(st) SFV: 34.1%, ADR 2~(nd)SFV: 44.3%) with no significant differences in ADR and PDR between the SFV and RFV arm. Mean number of adenomas per patient(APP) was increased in the RFV and SFV(APP RFV arm: 1~(st) SFV: 1.71; 2~(nd) RFV: 2.38; APP SFV arm: 1~(st) SFV: 1.83, 2~(nd)SFV:2.2). The majority of adenomas additionally found during second inspection in RFV or in SFV were located in the transverse and left-sided colon and were 5 mm in size.CONCLUSION Second inspection of the whole colon leads to increased adenoma detection with no differences between SFV and RFV. Hence, increased detection is most likely a feature of the second inspection itself but not of the inspection mode.  相似文献   
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Diastematomyelia is a congenital dysraphism of the spinal cord in which the affected segment is longitudinally divided by a band of fibrous tissue, cartilage, or bone. Diastematomyelia has been well described in the cervical, thoracic, lumbar, and sacral spinal cord; this paper presents a case involving the basicranium. Based on the early embryologic development of the basicranium and brain, this case demonstrates that the same mechanisms proposed as the origin of spinal diastematomyelia may also operate at a more cephalad level.  相似文献   
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BACKGROUND: Toxic epidermal necrolysis (TEN) is a severe and potentially fatal drug reaction characterized by an extensive skin rash with blisters and exfoliation, frequently accompanied by mucositis. The wounds caused by TEN are similar to second-degree burns and severe cases may involve large areas of skin loss. OBJECTIVES: Analysis of our results in patients with TEN and evaluation of the variety of therapeutic interventions that has been studied and suggested in TEN. PATIENTS/METHODS: Retrospective analysis of 19 consecutive patients with TEN treated in our burns centre between 1989 and 2004. RESULTS: Immediate withdrawal of any potentially fatal drug, maximum supportive care, and a restricted and tailored antibiotic, medical and surgical treatment regimen confined mortality to 21%, whereas prognosis scores like APACHE II and SCORTEN predicted mortality of 22 and 30%, respectively. A positive contribution of selective digestive decontamination is suggested but has yet to be established. CONCLUSIONS: Because of a potentially fatal outcome, fast referral of a patient suspected of TEN to a specialized centre (mostly a burns unit or specialized dermatology centre) for expert wound management and tailored comprehensive care is strongly advised and contributes to survival.  相似文献   
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OBJECTIVE: To analyse the image quality and diagnostic effectiveness of a new C-arm-based 3D imaging method (C-arm-CT) for intraoperative evaluation of screw osteosyntheses adjacent to a peripheral joint. MATERIALS AND METHODS: Insertion of screws into four cadaveric specimens simulated the surgical treatment of talus neck fractures. Ten orthopedic surgeons and 10 radiologists evaluated X-ray, C-arm fluoroscopy, C-arm-CT and CT images. RESULTS: The best image quality was obtained with X-rays (p < 0.001), followed by C-arm fluoroscopy (2D) and CT, with the C-arm-CT (3D) being rated lowest (p < 0.001). The most correct diagnoses were obtained with CT and C-arm-CT (with no statistical difference between them), while C-arm-fluoroscopy was inferior (p < 0.001) and X-rays were the worst (p < 0.05). CONCLUSIONS: Even if the image quality of C-arm-CT is definitely inferior to that of CT, screw misplacements can be reliably detected using C-arm-CT. As compared to the current standard procedures (intraoperative fluoroscopy and postoperative radiography), C-arm-CT performed better. C-arm-CT is ideally suited to the intraoperative diagnosis of high-contrast inquiries like bone fragments and OS material, especially at the extremities. Coupling of the new 3D imaging to existing navigation systems is possible. C-arm-CT will support the further development and implementation of open and minimally invasive surgical procedures.  相似文献   
5.
1背景 育龄妇女常见慢性下腹痛,可造成身体损害、情绪忧伤及导致巨大的健康服务费用。美国在这方面的花费超过8亿8千万美元(Mathias 1996)。英国全国数据库的一般性诊治资料显示,慢性下腹痛发病率及流行率与偏头痛、背部痛、哮喘发病率相似(Zondervan 1999)。  相似文献   
6.
One of the causes of implant failures in cemented implant-retained prostheses is the fracture of abutment screw or UCLA abutment. This article reports a case of simultaneous fracture of two UCLA abutments screws occurring in an implant-supported prosthesis placed in the mandibular molar region. The fractured structures were examined under scanning electron microscopy to investigate the probable causes of the failure, which were not related to failures on materials or fabrication of the screws, but rather were due to shear forces. The misfit in cemented prostheses may be the most likely cause of shear force generation.  相似文献   
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After p.o. administration of 5-piperidino-7-[N-pentyl-N-(beta- hydroxyethyl)]amino-s-triazolo[1,5-a]pyrimidine (1; AR 12463) more than 15 metabolites were isolated from urine and feces of male Wistar rats. Only small amounts of unchanged 1 were observed. The structure of 12 metabolites was elucidated or proposed on the basis of UV-, 13C NMR- and mass spectra. Main metabolites are 5-piperidin-4'-olyl-7-[N-pentyl-N-(beta- hydroxyethyl)]amino-s-triazolo[1,5-a]pyrimidine and 5-piperidin-4'-olyl-7-[N-pent-4-olyl-N-(beta-hydroxyet hyl)]amino-s- triazolo[1,5-a]pyrimidine. The other metabolites are mainly hydroxy- or ketopentyl derivatives and piperidinoles or piperidinones, respectively. Conjugates of most of the metabolites were identified, but the ratio phase-I/II metabolites was about 3:1. In contrast to trapidil, 5-methyl-7-diethylamino-s- triazolo[1,5-a]pyrimidine, no hydroxy derivatives of the bicyclic system were observed. The major part of unchanged 1 and metabolites is excreted via kidneys.  相似文献   
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