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101.
外源性AA引起兔动脉条收缩,呈剂量依赖性;EPA抑制AA收缩血管亦呈浓度依赖性;DHA对AA收缩血管作用无明显影响。破坏血管内皮后AA收缩血管作用大为减弱,EPA抑制AA收缩血管作用也几乎消失。吲哚美辛能阻断AA收缩兔主动脉条的作用。兔主动脉6-keto-PGF、TXB2及其比值随AA浓度升高而增加,低剂量EPA对前列腺素类代谢无明显影响,较大剂量时则降低上述指标。  相似文献   
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Abdominal radiography, excretory urography, retrograde pyelography, and computed tomography were performed in two patients who had undergone retrograde pyelography with thorium dioxide (Thorotrast) approximately 40 years ago. Both patients developed a transitional cell carcinoma due to suburothelial thorium deposition. Typical thorium densities were demonstrated at CT in the peripelvicalyceal area as well as in retroperitoneal lymph nodes. Elderly patients in whom radiographic examination reveals retained Thorotrast in the kidney should be followed up because of the high risk of renal carcinoma.  相似文献   
104.
Klatskin tumors of the bile ducts: sonographic appearance   总被引:4,自引:0,他引:4  
Meyer  DG; Weinstein  BJ 《Radiology》1983,148(3):803-804
The authors present 3 cases of surgically proved Klatskin tumor diagnosed by ultrasound alone. Sonographic features of these tumors include (a) dilatation of the intrahepatic biliary ducts but not the extrahepatic duct, (b) non-union of the right and left hepatic ducts, and (c) small, solid masses at the hepatic hilus. Local spread to the liver may also be seen. If the pancreas appears normal and no primary tumor can be found, Klatskin tumor can be diagnosed with a high degree of accuracy.  相似文献   
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In this paper, Bayesian decision procedures previously proposed for dose-escalation studies in healthy volunteers are reviewed and evaluated. Modifications are made to the expression of the prior distribution in order to make the procedure simpler to implement and a more relevant criterion for optimality is introduced. The results of an extensive simulation exercise to establish the properties of the procedure and to aid choice between designs are summarized, and the way in which readers can use simulation to choose a design for their own trials is described. The influence of the value of the within-subject correlation on the procedure is investigated and the use of a simple prior to reflect uncertainty about the correlation is explored.  相似文献   
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SUMMARY. This paper was presented to the Fifth Conference of the Institute of Psychotherapy and Counselling whose overall subject was Envy. I chose the subject of sibling rivalry because I have always found it a burning personal issue. Surprisingly not much has been written about it; so I hoped it would be interesting for a change to think about an aspect of envy that is a universal experience and yet different from the primary envy which Melanie Klein located in the motherbaby relationship and the state of part object relating. Rivalry and competition begin in the later developmental phase when the infant has achieved unit status, and when the two-person relationship has expanded into three- and multi-person relationships where the issues are loss, exclusion and intrusion. Then the experience of difference and otherness has to be mastered so that socialisation can take place.  相似文献   
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