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691.
Michel Labrecque John Pile David Sokal Ramachandra CM Kaza Mizanur Rahman SS Bodh Jeewan Bhattarai Ganesh D Bhatt Tika Man Vaidya 《BMC urology》2005,5(1):1-9
Background
Simple ligation of the vas with suture material and excision of a small vas segment is believed to be the most common vasectomy occlusion technique performed in low-resource settings. Ligation and excision (LE) is associated with a risk of occlusion and contraceptive failure which can be reduced by performing fascial interposition (FI) along with LE. Combining FI with intra luminal thermal cautery could be even more effective. The objective of this study was to determine the surgical vasectomy techniques currently used in five Asian countries and to evaluate the facilitating and limiting factors to introduction and assessment of FI and thermal cautery in these countries.Methods
Between December 2003 and February 2004, 3 to 6 major vasectomy centers from Cambodia, Thailand, India, Nepal, and Bangladesh were visited and interviews with 5 to 11 key informants in each country were conducted. Vasectomy techniques performed in each center were observed. Vasectomy techniques using hand-held, battery-driven cautery devices and FI were demonstrated and performed under supervision by local providers. Information about interest and open-mindedness regarding the use of thermal cautery and/or FI was gathered.Results
The use of vasectomy was marginal in Thailand and Cambodia. In India, Nepal, and Bangladesh, vasectomy was supported by national reproductive health programs. Most vasectomies were performed using the No-Scalpel Vasectomy (NSV) technique and simple LE. The addition of FI to LE, although largely known, was seldom performed. The main reasons reported were: 1) insufficient surgical skills, 2) time needed to perform the technique, and 3) technique not being mandatory according to country standards. Thermal cautery devices for vasectomy were not available in any selected countries. Pilot hands-on assessment showed that the technique could be safely and effectively performed by Asian providers. However, in addition to provision of supplies, introducing cautery with FI could be associated with the same barriers encountered when introducing FI in combination with LE.Conclusion
Further studies assessing the effectiveness, safety, and feasibility of implementation are needed before thermal cautery combined with FI is introduced in Asia on a large scale. Until thermal cautery is introduced in a country, vasectomy providers should practice LE with FI to maximize effectiveness of vasectomy procedure. 相似文献692.
继前报后,又从异叶梁王茶[Nothopanax davidii(France)Harms]树皮中分离得到两种五环三萜皂甙。经化学和波谱(IR,1HNMR,~(13)CHMR,1H-1HCOSY,13C-1H COSY,MS)分析,分别鉴定为3-O-α-(2’,4’-O-二乙酰基)-L-吡喃阿拉伯糖-3β-羟基齐墩果-12-烯-28,29-双羧酸-28-O-[α-L-吡喃鼠李糖(1-4)-β-D-吡喃葡萄糖(1—6)-β-D-吡喃葡萄糖]酯甙(Ⅲ),命名为异叶梁王茶甙Ⅲ和3-O-β-(2-O-乙酰基)-D-吡喃木糖-3β-羟齐墩果-12-烯-28,29-双羧酸甙(Ⅳ),命名为异叶梁王茶甙Ⅳ。这两种皂甙均系首次从植物中分出的新化合物。 相似文献
693.
CT of the pulmonary nodule: a cooperative study 总被引:31,自引:0,他引:31
Zerhouni EA; Stitik FP; Siegelman SS; Naidich DP; Sagel SS; Proto AV; Muhm JR; Walsh JW; Martinez CR; Heelan RT 《Radiology》1986,160(2):319-327
To evaluate the role of computed tomography (CT) in the investigation of pulmonary nodules, a special reference phantom that enabled CT densitometric measurements independent of variations between scanners and patients was used in ten institutions. A total of 384 nodules not considered calcified by conventional methods were examined; 118 (31%) proved to be benign, and in 65 of these (55%), unsuspected calcification was demonstrated. In 28 of the 65, definite calcification could be identified on thin-section CT scans by simple inspection of the scans at narrow windows. In the remaining 37, presence of calcification could not be clearly established without comparison with the reference CT number from the calibration phantom. CT was most effective in establishing the benignancy of nodules 3 cm or less in diameter and those with discrete or smooth margins. CT rarely yields a confident diagnosis of benign disease in larger nodules and in those with irregular or spiculated borders. After review of prior spot radiographs, low kilovolt peak spot radiographs, and conventional tomograms, the authors conclude that thin-section CT aided by a reference phantom in equivocal cases should be an integral part of the diagnostic approach to the pulmonary nodule. 相似文献
694.
695.
696.
697.
698.
Pulmonary hamartoma: CT findings 总被引:13,自引:0,他引:13
Siegelman SS; Khouri NF; Scott WW Jr; Leo FP; Hamper UM; Fishman EK; Zerhouni EA 《Radiology》1986,160(2):313-317
Forty-seven patients with a proved (n = 31) or presumed (n = 16) diagnosis of pulmonary hamartoma were studied prospectively by thin-section computed tomography (CT). CT criteria for hamartoma included a diameter of 2.5 cm or less, a smooth edge, and focal collections of fat or fat alternating with areas of calcification. No case of cancer (n = 283) or metastatic disease (n = 72) fulfilled these criteria. Seventeen hamartomas with no detectable calcium or fat were not diagnosed by means of CT. Two other lesions contained diffuse calcium deposits. In 28 lesions, a CT diagnosis of hamartoma was based on the detection of fat (n = 18) or calcium plus fat (n = 10). Twelve such cases were proved histologically by means of thoracotomy or needle biopsy; the remainder, including eight in asymptomatic patients aged 65 years or older, were managed with conservative follow-up. 相似文献
699.
Fracture nonunion: CT assessment with multiplanar reconstruction 总被引:2,自引:0,他引:2
Kuhlman JE; Fishman EK; Magid D; Scott WW Jr; Brooker AF; Siegelman SS 《Radiology》1988,167(2):483-488
Nineteen patients with suspected or possible fracture nonunion underwent computed tomography (CT) with multiplanar reconstruction (MPR). Each case represented a difficult problem in fracture management in which clinical and conventional radiographic examinations had failed to provide a definitive diagnosis. CT with MPR demonstrated nonunion in 13 of 19 cases by delineating the lack of bone bridging across the fracture site in multiple planes. Variable amounts bridging were detected in six cases, indicating partial healing or delayed union. Evaluation of fracture healing with MPR was possible despite remaining metal hardware (ten cases), multiple operations (15 cases), or bone grafting (five cases). CT with MPR aided surgical planning and affected treatment options by providing a more detailed assessment of malalignment and angular deformities, the magnitude of the gap in bone, and the integrity of the adjacent weight-bearing joints in multiple projections. It is an important new modality for evaluating fracture nonunion. 相似文献
700.