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91.
Ectopic ureter and ureterocele: their varied sonographic manifestations   总被引:1,自引:0,他引:1  
The sonographic examinations of four patients with simple ectopic ureters and 11 with ectopic ureteroceles were reviewed to determine distinguishing characteristics. Ectopic ureters, in cases of extreme dilatation and tortuosity, sometimes mimic multiseptated, cystic abdominal masses. However, the proximal portions of some severely dilated ureters are surprisingly small. Ectopic ureters sometimes indent the lower vesical wall, simulating a ureterocele. Ectopic ureteroceles are dynamic structures, changing in shape and size according to intravesical pressure. The lower pole of a duplex kidney may be difficult to detect because of displacement by the dilated upper renal pelvis and ureter. The renal parenchyma associated with an ectopic ureter may be equally difficult or impossible to find because of diminutive dysplasia or, less commonly, acquired atrophy. Dysplasia is characterized sonographically by highly echogenic parenchyma, lack of corticomedullary differentiation, and occasionally massive enlargement by cysts. Ectopic ureters and ureteroceles can be identified by fetal sonography.  相似文献   
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The Kheda project experience has shown that bio-environmentalcontrol of malaria is feasible, cost effective and ecologicallysound. It clearly brings out the need to consider health issuesat the planning stage of all developments. Bio-environmentalcontrol of malaria is suggested as the first line of attackfor the control of mosquitoes, malaria and other mosquito-bornediseases. Insecticides may be reserved for short-term use. Thiswill enable judicious and selective use of insecticides in solelyepidemic situations. The growing problem of resistance to insecticidesin mosquitoes as well as environmental pollution, can then besolved on a long term basis.  相似文献   
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Six normal and 16 neoplastic colorectal specimens were examined with 8.5-MHz ultrasound (US). An articulated system facilitated precise spatial correlation between US and histologic sections. Images were blindly interpreted and then compared with histologic results. All six normal specimen showed five distinct echo layers and were distinguished from neoplastic specimens by all the observers. The central echogenic layer, corresponding to the submucosa, is useful in determining the depth of origin of a neoplasm and the presence of submucosal invasion. US had an accuracy of 92.5% in demonstrating invasion of the submucosa and 77% for invasion of the muscularis externa. For mucosal neoplasms with invasion through the muscularis externa and extension into the subserosal tissues, nearly 90% of US interpretations were correct. High-frequency US may be useful in determining the depth of invasion of mucosal tumors with respect to the submucosa and in differentiating mucosal from extramural masses.  相似文献   
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Rholl  KS; Lee  JK; Ling  D; Sicard  GA; Griffith  RC; Freeman  M 《Radiology》1986,160(1):113-117
Findings of magnetic resonance (MR) imaging in acute renal rejection and acute tubular necrosis (ATN) were studied in dogs. On T1-weighted images, corticomedullary differentiation was absent in kidneys undergoing acute rejection. The loss of corticomedullary differentiation in these kidneys was secondary to a decrease in the relative signal intensity of the cortex, indicating prolongation of the T1 relaxation time of the cortex. In contrast, corticomedullary differentiation was preserved on T1-weighted images of autotransplanted kidneys and kidneys with ATN. MR imaging findings correlated with changes in water content in these three groups of kidneys. Kidneys undergoing acute rejection showed a marked increase in water content compared with kidneys in the other two groups. No change in fat content was found in any group.  相似文献   
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Baker  R; Fraser  RC 《Family practice》1997,14(2):107-111
BACKGROUND: It is commonly accepted that ownership is an important factor in determining the acceptability and use of protocols or guidelines. OBJECTIVES: We aimed to determine whether Medical Audit Advisory Groups (MAAGs) are prepared to accept and use audit protocols developed systematically by an external agency. METHOD: A postal questionnaire was sent to all 105 MAAG chairmen in England and Wales to seek their views on the external development of protocols, the inclusion of evidence-based prioritized criteria, the general design of the protocols issued by the Lilly Audit Centre and the numbers of practices reported by MAAGs as making use of at least one of the first four protocols issued. RESULTS: Ninety-five MAAGs (90%) responded. Of these, 86% were in favour of the external development of protocols, and 98% and 94%, respectively, found evidence-based and prioritized criteria valuable; 98% felt the overall design and content of the Audit Centre protocols were excellent or good. A total of 1018 practices was known to have made use of one of these protocols, 261 taking part in multi-practice audits organized by their MAAGs. CONCLUSION: Ownership is not necessarily more important than scientific credibility and/or perceived utility. Externally developed audit protocols containing evidence-based, prioritized review criteria are acceptable to MAAGs, which are prepared to recommend their use in practice. Accordingly, such systematically developed protocols offer a promising and practical method for improving clinical effectiveness. Further research is needed, however, to determine the comparative impact on standards of care of protocols and other methods such as clinical guidelines.   相似文献   
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