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51.
Synthesis and cholinergic properties of bis[[(dimethylamino)methyl]furanyl] analogues of ranitidine.
J W Sowell Y Tang M J Valli J M Chapman L A Usher C M Vaughan J W Kosh 《Journal of medicinal chemistry》1992,35(6):1102-1108
The histaminergic H2 antagonist, ranitidine, has also been found to significantly inhibit acetylcholinesterase (AChE) in vitro. In an effort to develop novel, nonquaternary AChE inhibitors capable of penetrating into the CNS and alleviating the cholinergic deficit characteristic of Alzheimer's disease, a series of bis[[(dimethylamino)methyl]furanyl] analogues of ranitidine has been synthesized. All compounds were evaluated for human erythrocyte AChE inhibitory activity and compared to ranitidine, physostigmine, and tetrahydro-9-aminoacridine (THA). The most active AChE inhibitors were N,N'-disubstituted derivatives of 2-nitro-1,1-ethenediamine and 4,6-dinitro-1,3-benzenediamine, with compound 8 demonstrating activity greater than physostigmine. Deletion of the diaminonitroethene group in a series of alkyl and aryl bis-thioethers, yielded a number of slightly less active compounds, comparable in potency to THA. The 13 most active AChE inhibitors all demonstrated a more selective inhibition of AChE, as opposed to butyrylcholinesterase inhibition, than did THA. Compounds 3 and 22 were equally active to THA in potentiating rat ileal contractions. Binding studies demonstrated M1 and M2 cholinergic receptor affinities slightly greater than or equal to THA. Differential receptor binding studies showed compound 12 resembled THA in agonist/antagonist activity. Compounds 11-13 significantly elevated mouse brain acetylcholine levels, when administered at 80% of their approximate lethal doses, but were less active than THA or physostigmine. 相似文献
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53.
本文建立了在常温常速离心条件下进行样品预处理的人血浆三尖杉酯碱高效液相色谱荧光测定法。本法批内CV%为3.08~3.47%,批间CV%为4.36~5.28%,回收率范围为93.6~95%,标准曲线在12.5~500ng/ml范围内线性良好(r=0.998)。方法简单、快速、准确,适于临床应用。 相似文献
54.
55.
注射吸毒致破伤风的临床特点及分析 总被引:1,自引:0,他引:1
目的探讨注射吸毒致破伤风的诊断与治疗。方法回顾性分析了9例注射吸毒者破伤风的临床资料。结果9例注射吸毒致破伤风的病人中,5例治愈,4例死亡,死亡原因:3例因呼吸肌痉挛和分泌物过多阻塞呼吸道窒息死亡,1例因呼吸衰竭死亡。结论注射后皮肤和软组织感染可认为是引起破伤风外伤伤口。注射吸毒破伤风应按重症破伤风处理。及时气管切开或气管插管机械辅助呼吸可降低死亡率。 相似文献
56.
本文报告了我科1978~1990年间收治的降突性皮纤维肉瘤23例,均经组织学证实.治疗以手术切除为主,术后局部复发率为65.2%.无一例发生转移.切除不彻底是复发的主要原因.作者指出广泛切除是防止复发的主要措施,手术前后的放疗有可能减少复发. 相似文献
57.
Parents and children who have been prescribed an Epipen are often unable to demonstrate its correct administration. One contributory factor may be that doctors are unfamiliar with the EpiPen and are unable to demonstrate the correct administration of the pen to the family. The aim of this study was to determine the rate of correct EpiPen demonstration by junior and Senior Medical Staff at a major tertiary paediatric Hospital. Junior and Senior medical staff were scored on their ability to correctly use the EpiPen trainer. A 6 step scoring system was used. One-hundred doctors were recruited (Residents n = 31, Senior Residents n = 39, Fellow/Consultants n = 30). Junior and Senior Medical staff had similar scores for EpiPen demonstration, the number that needed to read the EpiPen instructions prior to use and the frequancy of accidental self-injection into the thumb. Only two doctors (2%) demonstrated all 6 administration steps correctly. The most frequent errors made were not holding the pen in place for >5 seconds (57%), failure to apply pressure to activate (21%), and self-injection into the thumb (16%). Ninety five doctors needed to read the instructions, and of these, only 39 (41%) then proceeded to correctly demonstrate the remaining 5 steps. Forty-five doctors had previously dispensed an EpiPen, but only three demonstrated its use to parents/children with a trainer. The majority of doctors do not know how to use an Epipen and are unable to provide appropriate education to parents/children. In 37% of cases, the demonstration would not have delivered adrenaline to a patient. 相似文献
58.
59.
Churk-Yan Tang 《Ophthalmic & physiological optics》1993,13(2):169-174
Eyewire shapes of some currently available spectacle frames were constructed mathematically and weights of spherical lenses cut to these shapes were computed for different decentrations in three commonly used lens materials. The results confirm a previous observation that the edged shape of a negative lens has only a minor effect on its weight, although this is often not the case for positive lenses. The appropriate diameters of circular centred lenses to be used in comparing lens weight for different materials were also examined Relative to those adopted in previous studies, it was found that the weight of a larger lens, 58 mm diameter for negative lenses and 65 mm diameter for positive lenses, would more adequately represent the average weight of edged lenses in modern spectacle frames. 相似文献
60.
MY Mancao LJ Sindel PH Richardson FM Silver 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(1):118-120
Croup is an acute infectious illness usually occurring in children; it is characterized by brassy cough and stridor. The main pathogens include mainly parainfluenza and influenza viruses. Recently there have been reports of prolonged croup caused by the herpes simplex viruses. We report two cases of prolonged croup due to herpes simplex types 1 and 2. We also review and summarize the reported pediatric cases of herpetic croup. 相似文献