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101.
7-(1,7-双取代-1,4-二氢-4-酮-1,8-萘啶-3-甲酰氨基)头孢菌素的合成 总被引:1,自引:0,他引:1
本文报道了以1,7-双取代-1,4-二氢-4-酮-1,8-萘啶-3-羧酸,用混合酸酐法与7-ACA,7-ADCA,7-ACT和7-ACD缩合,合成了24个1,7-双取代-1,4-二氢-4-酮-1,8-萘啶-3-甲酰胺头孢菌素衍生物,通过葡聚糖凝胶(Sephadex LH-20)及离心薄层层析纯化精制,得到纯品。体外抑菌试验结果表明:大多数新头孢菌素衍生物对革兰氏阳性菌具有较好的抗菌作用。尚有一些新头孢菌素衍生物对某些革兰氏阴性菌具有中等敏感程度。 相似文献
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To test the feasibility of teleradiology for use with excretory urograms obtained in the emergency department in cases for suspected renal colic, radiographs from 43 patients were digitized, transmitted via standard phone lines, and viewed on a video monitor 2 miles distant. Diagnostic interpretations of the video image and the original radiograph were reviewed for degree of concordance. The video and film images of the 27 examinations showing obstruction were interpreted with 100% correlation. Agreement as to the site of obstruction was present in 93% of cases. Only two-thirds of renal and ureteral calculi seen on the radiographs were discerned on the video images, however. Teleradiology proved as useful for ongoing monitoring and modification of these examinations as for initial interpretation. 相似文献
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Tomoko Shimakawa David W. Weingaertner Diane M. Schmit Mary M. Brandt 《Journal of food composition and analysis》2009
In the United States, nutrition labeling for raw fruits, vegetables, and fish is currently voluntary. In order to encourage retail stores that sell these foods to participate in the voluntary nutrition labeling program and to be compliant with the guidelines, the United States Food and Drug Administration (FDA) has developed downloadable and printable posters containing nutrition information for the 20 most frequently consumed raw fruits, vegetables, and fish in the United States. The FDA has made the posters available on its website (http://www.cfsan.fda.gov/nutinfo.html), and has urged retail stores to download and print the posters and to display them in their stores for consumers to use in making purchase decisions. In developing these posters, FDA followed the agency's guidelines for voluntary nutrition labeling. The names and nutrition labeling values for the raw fruits, vegetables and fish are based on the updated nutrition labeling regulation published in the Federal Register on August 17, 2006, which corrected the July 25, 2006 final rule. FDA issued a Constituent Update (electronic newsletter) and contacted trade associations representing retail food stores to inform them about the posters. 相似文献
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Arteriovenous malformations of the extremities: MR imaging 总被引:3,自引:0,他引:3
Eight patients with angiographically proved arteriovenous malformations (AVMs) of the extremities (seven congenital, one posttraumatic) were evaluated with magnetic resonance (MR) imaging using a 0.35-T superconducting system and spin-echo pulse sequences. Congenital AVMs appeared as accumulations of dilated tortuous blood vessels infiltrating the involved muscles. A posttraumatic acquired AVM of the shoulder consisted of a large feeding artery associated with a pseudoaneurysm and a soft-tissue mass. MR imaging allowed precise anatomic localization and provided details concerning the size and extent of the AVMs. The relationship of AVMs to specific muscle groups, bones, and vascular structures could be accurately determined. Although major feeding and draining vessels were identified, the exact arteries and veins supplying and draining the AVM could not be ascertained. Images obtained in the transverse plane consistently yielded the most useful information. MR imaging and angiography may be complementary techniques in the initial evaluation, follow-up, and treatment planning of AVMs of the extremities. 相似文献
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