小型猪在异种移植中的应用前景

目的 建立狂犬病病毒感染动物疾病模型.方法 狂犬病病毒CVS-B2C毒株以10LD50剂量腿部肌肉注射接种4～6周龄的BALB/c小鼠,0.2 mL/只,于BSL2实验室负压IVC设备内饲养观察,并对其模型进行评价.结果 小鼠接种狂犬病病毒后一周左右就出现临床症状,表现为饮食量下降,毛皮慢慢失去原先的光泽,体重下降,并出现麻痹等症状,进而死亡,部分小鼠出现躁狂的症状或抽搐性和强直性痉挛,而对照组小鼠则表现正常.DFA法检测结果:感染上狂犬病毒的小鼠脑组织涂片中出现特异性荧光抗体染色反应,而对照组动物的小鼠脑组织涂片未出现荧光抗体染色反应.RT-PCR法检测结果:从感染小鼠脑组织标本中提取病毒RNA,引物扩增出的目的 基因片段,大小约为1kb,为N蛋白.免疫组化法检测结果:感染狂犬病毒的小鼠脑切片显示出棕色阳性颗粒,对照组小鼠脑切片染色阴性.病理检测结果:HE染色可见感染小鼠脑组织炎性细胞浸润.神经细胞胞质内出现内基体以及神经细胞退行性病变.结论 成功的复制出小鼠狂犬病病毒感染模型,为研究和控制狂犬病奠定了基础.     

ENDOSCOPIC MUCOSAL RESECTION AND SUBMUCOSAL DISSECTION METHOD FOR LARGE COLORECTAL TUMORS

The goal of endoscopic mucosal resection (EMR) is to allow the endoscopist to obtain tissue or resect lesions not previously amenable to standard biopsy or excisional techniques and to remove malignant lesions without open surgery. In this article, we describe the results of conventional EMR and EMR using an insulation‐tipped (IT) electrosurgical knife (submucosal dissection method) for large colorectal mucosal neoplasms and discuss the problems and future prospects of these procedures. At present, conventional EMR is much more feasible than EMR using IT‐knife from the perspectives of time, money, complication, and organ preservation. However, larger lesions tend to be resected in a piecemeal fashion; and it is difficult to confirm whether EMR has been complete. For accurate histopathological assessment of the resected specimen en bloc EMR is desirable although further experience is needed to establish its safety and efficacy. Further improvements of in EMR with special knife techniques are required to simply and safely remove large colorectal neoplasms.     

Caffeic acid improves the bioavailability of l‐dopa in rabbit plasma

The impacts of caffeic acid (3,4‐dihydroxycinnamic acid, CA) on the pharmacokinetics of levodopa (L‐dopa) were studied in rabbits. A single dose of 5/1.25 mg·kg^?1 l ‐dopa/carbidopa was administered alone or was co‐administered with three different doses of caffeic acid (2.5, 5, and 10 mg·kg^?1), or a single dose of 5 mg·kg^?1 caffeic acid was administered alone via an intramuscular route to six rabbits each in a crossover treatment protocol. Plasma levels of l ‐dopa, 3‐O‐methyldopa (3‐OMD), caffeic acid, and ferulic acid were determined and subsequently used to calculate their pharmacokinetic parameters. The results indicated that caffeic acid administered at a dose of 10 mg·kg^?1 decreased about 22% of the peripheral formation of 3‐OMD and about 31% of the C_max of 3‐OMD. In addition, the metabolic ratios (MR, AUC of 3‐OMD/AUC of L‐dopa) decreased by about 22%. Results also indicated that caffeic acid significantly decreased the proportion of 3‐OMD (p < 0.05). In contrast, the parameters of neither caffeic acid nor ferulic acid were significantly affected by l ‐dopa/carbidopa. In conclusion, caffeic acid at a dose of 10 mg·kg^?1 can significantly affect the COMT metabolic pathway of L‐dopa. Copyright © 2009 John Wiley & Sons, Ltd.     

Development of specificity in corticospinal connections by axon collaterals branching selectively into appropriate spinal targets

Corticospinal projections in adult rodents arise exlusively from layer V neurons in the sensorimotor cortex. These neurons are topographically organized in their connections to spinal cord targets. Previous studies in rodents have shown that the mature distribution pattern of corticospinal neurons develops during the first 2 weeks postnatal from an initial widespread pattern that includes the visual cortex to a distribution restricted to the sensorimotor cortex. To determine whether specificity in corticospinal connections also emerges from an intially diffuse set of projections, we have studied the outgrowth of corticospinal axons and the formation of terminal arbors in developing hamsters. The sensitive fluorescent tracer 1, 1′, dioctadecyl-3, 3, 3′, 3′-tetramethylindocarbocyanine perchlorat (DiI) was used to label corticospinal axons from the visual cortex or from small regions of the forelimb or hindlimb sensorimotor cortex in living animals at 4–17 days postnatal. Initially axon outgrowth was imprecise. Some visual cortical axons extended transiently beyond their permanent targets in the pontine nuclei, by growing through the pyramidal decussation and in some cases extending as far caudally as the lumbar enlargement. Forelimb sensorimotor axons also extended past their targets in the cervical enlargement, in many cases growing in the corticospinal tract to lumbar levels of the cord. By about 17 days postnatal these misdirected axons or axon segments were withdrawn from the tract. Despite these errors in axon trajectories within the corticospinal tract, terminal arbors branching into targets in the spinal gray matter were topographically appropriate from the earliest stages of innervation. Thus visula cortical axons never formed connections in the spinal cord, forelimb sensorimotor axons arborized only in the cervical enlargement, and hindlimb cortical axons terminated only in the lumbar cord at all stages of development examined. Corticospinal arbors formed from collaterals that extended at right angles from the shafts of primary axons, most likely by the process of interstitial branching after the primary growth cone had extended past the target. Once collaterals extended into the spinal gray matter, highly branched terminal arbors formed within 2–4 days, beginning at about 4 and 8 days postnatal for the cervical and lumbar enlargements, respectively. These results show that specificity in connectivity is achieved by selectivty growth of axon collaterals in to appropriate spinal targets from the beginning and not by the later remodeling of intially diffuse connections. In contrast, errors occur in the initial outgrowth of axons in the corticospinal tract, which are subsequently corrected. Copyright © 1994 Wiley-Liss, Inc.     

地西泮、苯巴比妥、普萘洛尔、和西咪替丁对大鼠肝微粒体安定氧化代谢的影响

研究地西泮、苯巴比妥、普萘洛尔和西咪替丁对地西泮氧化代谢的影响及其药酶蛋白的初步分析，应用HPLC，SDS－聚丙烯酰胺凝胶电泳和薄层扫描测定地西泮及其代谢物，并对大鼠肝微粒体和酶蛋白进行分离和含量测定，结果表明地西泮，普萘洛尔和西咪替丁使肝微粒体中P－450含量明显降低，地西泮和普萘洛尔明显抑制地西泮C3－羟化活性，大剂量普萘洛尔尚能抑制地西泮N－脱甲基，苯巴比妥明显诱导P－450生成，增强地西泮N－脱甲基和C3－羟化酶活性及分子量为51，000和59，000的电泳蛋白带，而地西泮，普萘洛尔则呈抑制作用，并发现，地西泮N－脱甲基酶活性和分子量为59，000蛋白含量呈线性相关（P＜0．05），而C3－羟化酶活性则与51，000蛋白含量呈线性相关（P＜0．01），因此地西泮C3－羟化代谢可能与51，000的P－450酶蛋白有关，而N－脱甲基代谢则可能与59，000的P－450酶蛋白有关。     

Effects of Diazepam,Phenobarbital,Propranolol,and Cimetidine on Diazepam Oxidizing Isoenzymes in Rat Liver Microsomes

研究地西泮、苯巴比妥、普萘洛尔和西咪替丁对地西泮氧化代谢的影响及其药酶蛋白的初步分析，应用ＨＰＬＣ，ＳＤＳ聚丙烯酰胺凝胶电泳和薄层扫描测定地西泮及其代谢物，并对大鼠肝微粒体和酶蛋白进行分离和含量测定。结果表明地西泮、普萘洛尔和西咪替丁使肝微粒体中Ｐ４５０含量明显降低。地西泮和普萘洛尔明显抑制地西泮Ｃ３羟化活性，大剂量普萘洛尔尚能抑制地西泮Ｎ脱甲基。苯巴比妥明显诱导Ｐ４５０生成，增强地西泮Ｎ脱甲基和Ｃ３羟化酶活性及分子量为５１，０００和５９，０００的电泳蛋白带，而地西泮、普萘洛尔则呈抑制作用。并发现，地西泮Ｎ脱甲基酶活性和分子量为５９，０００蛋白含量呈线性相关（Ｐ＜０．０５），而Ｃ３羟化酶活性则与５１，０００蛋白含量呈线性相关（Ｐ＜０．０１）。因此地西泮Ｃ３羟化代谢可能与５１，０００的Ｐ４５０酶蛋白有关，而Ｎ脱甲基代谢则可能与５９，０００的Ｐ４５０酶蛋白有关。     

不锈钢清创车在外伤伤口清创中的应用

清洗伤口时病人血液常常易溅到医护人员的衣服及地面上，造成环境污染，甚至威胁医护人员的健康。我科于2002年3月设计了不锈钢清创车，经过2年临床使用，效果满意。     

三种粪便隐血试验的比较研究

粪便隐血试验是检测消化道微量出血的重要手段。本文用三种隐血试验:血红蛋白定量试验(HQT)、反向间接血球凝集试验(RPHA)和联苯胺试验(BT)对不同消化道疾病患者的粪便进行检测。结果表明隐血的检出用HQT和RPHA较BT更为特异和敏感。     

Blood cholinesterase levels among agricultural workers in four Asian countries

In this study whole blood cholinesterase activities were determined (tintometric method) of agricultural pesticide users exposed to organophosphorus compounds in Indonesia, Malaysia, Sri Lanka and Thailand. Analysis of the data demonstrated a universal relationship between cholinesterase levels and the time between the last exposure to organophosphorus compounds and the day of blood collection for cholinesterase determination. It is suggested that it takes approximately 5 days before whole blood cholinesterase levels revert to their normal values. No relationship between whole blood cholinesterase levels and the sex of pesticide users was demonstrated except in Sri Lanka where female sprayers had lower values. It is suggested that these lower values are associated with the anaemic status of female agricultural workers. No relationship between whole blood cholinesterase level and age was demonstrated. The measurement of pre-exposure cholinesterase values is essential for comparison of values after pesticide application.