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1.
Background Percutaneous abdominal aortic aneurysm(AAA) repair has been previously described using the "preclose"technique and general endotrachial anesthesia (GA).  相似文献   
2.
Porphyrin dimers 9 with either linkages and possible isomers bis[1-[6,7-bis[2-(methoxycarbonyl)ethyl]-1,3,5,8-tetramethyl-2- vinylporphin-4-yl]ethyl] ether (10) bis[1-[6,7-bis[2-(methoxycarbonyl)ethyl]-1,3,5,8-tetramethyl-4- vinylporphin-2-yl]ethyl] ether (11), and 1-[6,7-bis[2-(methoxycarbonyl)ethyl]-1,3,5,8-tetramethyl-2-vinylporph in- 4-yl]ethyl 1-[6,7-bis[2-(methoxycarbonyl)ethyl]-1,3,5,8-tetramethyl-4-vinylporph in- 2-yl]ethyl ether (12) were synthesized from the corresponding (1-hydroxyethyl)vinyldeuteroporphyrin IX dimethyl esters (Hvd). The pure Hvd isomers 2-(1-hydroxyethyl)-4-vinyldeuteroporphyrin IX dimethyl ester (7) and 4-(1-hydroxyethyl)-2-vinyldeuteroporphyrin IX dimethyl ester (8) were obtained from 2-acetyl-4-(1-hydroxyethyl) deuteroporphyrin IX dimethyl ester (3) and 4-acetyl-2-(1-hydroxyethyl)deuteroporphyrin IX dimethyl ester (4). Porphyrins 3 and 4 were prepared either by partial reduction of 2,4-diacetyldeuteroporphyrin IX dimethyl ester (2) or by oxidation of hematoporphyrin IX dimethyl ester (1) by using tetra-n-propylammonium perruthenate (Prn4N)(RuO4) with N-methylmorpholine N-oxide as an oxidizing agent. The in vivo photosensitizing ability and therapeutic ratios of dimers 9-12 were compared with that of Photofrin II in the SMT-F tumor growing subcutaneously in DBA/2 Ha mice. These dimers were found to have better tumoricidal activity than Photofrin II with reduced skin phototoxicity.  相似文献   
3.
BACKGROUND: The dopamine transporter (DAT) is known to be a key regulator of dopamine, and recent studies of genetics, treatment, and imaging have highlighted the role of DAT in attention-deficit/hyperactivity disorder (ADHD). The findings of in vivo neuroimaging of DAT in ADHD have been somewhat discrepant, however. METHOD: Dopamine transporter binding was measured using a highly selective ligand (C-11 altropane) and positron emission tomography (PET). The sample consisted of 47 well-characterized, treatment-na?ve, nonsmoking, non-comorbid adults with and without ADHD. Additionally, control subjects had few symptoms of ADHD. RESULTS: Results showed significantly increased DAT binding in the right caudate in adults with ADHD compared with matched control subjects without this disorder. CONCLUSIONS: These results confirm abnormal DAT binding in the striatum of adults with ADHD and provide further support that dysregulation of DAT may be an important component of the pathophysiology of ADHD.  相似文献   
4.
Contact lens disinfection systems were evaluated for their effectiveness in killing Acanthamoeba castellanii and Acanthamoeba polyphaga trophozoites and cysts. Amoebae were inoculated into commercially available contact lens cleaning and soaking solutions. At intervals varying from 30 minutes to 24 hours, solutions were filtered. The filters were removed and cultured for Acanthamoeba organisms. Striking differences were observed in the abilities of the different disinfecting solutions to kill the organisms. Solutions containing chlorhexidine were effective at very short exposure times. Solutions containing benzalkonium chloride required slightly longer exposure times but were faster than solutions containing only thimerosal. Solutions containing sorbate, polyaminopropyl biguanide, or polyquaternium-1 were not effective at killing Acanthamoeba organisms in the time allotted for the experiment. Solutions containing hydrogen peroxide were quite effective if the agent was not prematurely catalyzed. A. polyphaga generally required longer exposure to disinfectants than did A. castellanii for complete inhibition to occur.  相似文献   
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Urine drug testing has become an increasingly controversial issue in today's society. In this paper, several issues involved in urine drug testing are discussed. These include the limitations of the accuracy of urine testing, testing in schools, athletics, the military and industry, and the legalities of drug testing. Also discussed is background information about urine drug screening and key factors in obtaining specimens for testing. Conclusions about the role of urine drug testing in the battle against substance abuse are drawn.  相似文献   
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华蟾蜍毒素对离体豚鼠输精管的作用   总被引:3,自引:0,他引:3  
韩永晶  张力  崔荣芬 《药学学报》1992,27(4):252-255
华蟾蜍毒素(华蟾素)使离体豚鼠输精管产生剂量依赖性收缩反应,利血平化豚鼠输精管及冷藏输精管对华蟾素反应减弱。给酚妥拉明、维拉帕米后,输精管对华蟾素反应均受抑制,溴苄胺可使反应潜伏期缩短。结果提示华蟾素收缩输精管反应可能与其促进肾上腺素能神经末稍NA释放有关。  相似文献   
9.
The role of excitatory amino acids (EAAs) in the excitation of monkey spinothalamic tract (STT) neurons following activation of cutaneous primary afferent fibers by noxious and non-noxious stimuli was investigated. The responses of STT neurons to either NMDA or non-NMDA EAA ligands were blocked by infusion of specific antagonists through a microdialysis fiber into the region surrounding the cells. Our results show that blockade of non-NMDA receptors results in a nearly complete elimination of the responses of STT neurons to all stimuli. Blockade of NMDA receptors results in an attenuation of the responses to noxious stimuli but, in addition, prevents the development of the sensitization of STT neurons that is often observed after intradermal injection of capsaicin. These observations further support a role of EAAs in the transmission of sensory information from primary afferent fibers to dorsal horn neurons and a role for NMDA receptors in the generation of hyperalgesia.  相似文献   
10.
PURPOSE: Many behavioral studies have found impaired perception of dynamic visual stimuli in dyslexia and several neuroimaging studies have found reduced activation of the human motion area MT+ in dyslexia. These results are often interpreted as a magnocellular (MC) deficit in dyslexia. It has also been claimed that colored filters can help dyslexics to read. One defining feature of the MC-pathway is a greater weight for L-cone input than M-cone input, and at most very weak S-cone input. We measured the subjective speed matches between L-, M-, and S-cone isolating stimuli in good and poor readers. METHODS: Subjects performed a speed-matching task with drifting cone-isolating stimuli to find the point of subjective equality between two drifting patterns. Such a task is known to activate cortical area MT+, presumably via the MC-pathway. RESULTS: L- to M-cone speed-match ratios were negatively correlated with single-word (r=-0.46) and irregular-word reading (r=-0.56) but not with non-word reading. CONCLUSIONS: Results suggest that relative L-cone sensitivity within the MC-pathway may limit orthographic reading performance.  相似文献   
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