Role of EDRF in the Regulation of Shear Rate in Large Coronary Arteries in Conscious Dogs

To determine whether dilation of large coronary arteries normalizes shear during increased flow following brief occlusion, six dogs were instrumented to measure aortic and left ventricular pressures, left circumflex coronary artery external diameter, and coronary blood flow. The coronary artery was occluded for 15 or 30 s. Data were obtained before and after blockade of EDRF synthesis with nitro-L-arginine. Internal coronary artery diameter and wall shear were calculated on a moment-to-moment basis and the area under the flow curve was measured. Peak flow and shear rate were unaffected by NLA or by the occlusion duration. Flow curve area increased with the duration of occlusion. Internal and external diameters increased significantly for 15 s occlusions before NLA (by 4 ± 1% in external diameter and by 11 ± 4% in internal diameter) and for 30 s occlusions before NLA (by 5 ± 1% in external diameter and by 14 ± 5% in internal diameter) but not after NLA. Adenosine infusions of 0.05, 0.10, 0.50, and 1.0 μmol/kg/min were also used to dilate the coronary arteries. With each infusion, flow, shear and diameter were allowed to reach steady state. Steady state shear was reduced only slightly and did not approach the baseline state. We conclude that increased shear rate causes an increase in coronary artery diameter which is EDRF dependent. Increased coronary artery diameter during reactive hyperemia and adenosine infusions did not normalize wall shear.     

益母草防治初发期急性肾小管坏死的实验研究

ＳＤ成年雄性大鼠，禁止１６小时，肌注甘油引起急性肾小管坏死（ＡＴＮ），于其初发期给予不同药液，观察到益母草组３、２４及４８小时Ｂｃｒ升高值，２４及４８小时ＢＵＮ升高值均明显低于自来水组和单纯禁水组，而与校正对照异搏停组近似，肾组织损伤程度亦明显减轻。结果表明，益母草对初发期急性肾小管坏死（ＩＡＴＮ）有一定的防治作用。     

健侧颈7移位治疗臂丛神经根性撕脱伤最佳时间选择的实验研究

健侧颈７移位治疗臂丛神经根性撕脱伤手术分第一阶段（健侧颈７移位到移植神经），第二阶段（移植神经另一端移植修复患侧神经），二次手术间隔多少时间才能获得最好的神经再生？选用ＳＤ大鼠及健侧颈７移位的实验模型，按二次手术间隔时间的不同（０、１、２、３、４、８、１６周）分成７组，在第二次术后１２周，进行电生理测定肌张力恢复率及组织切片的形态学观察，结果证实二次手术最佳间隔时间为４～８周．此结果可提供临床参考．     

成核效应蛋白在泡凝聚融合过程中作用的初步研究

为了探讨成核效应蛋白在泡凝聚、融合过程中的作用，作者研究了胆汁中主要的促成核蛋白系统—ＣｏｎＡ结合蛋白对模拟胆汁泡的形态与脂类组成的影响，发现ＣｏｎＡ结合蛋白在加快泡凝聚与融合的同时，也使泡胆固醇增加，磷脂减少，泡胆固醇／磷脂比增高，认为成核效应蛋白促泡凝聚与融合的本质是改变了泡胆固醇饱和度。作者的初步研究还发现泡相蛋白虽量微却具有强的促成核活性；几种已知的成核效应蛋白在泡相与微胶粒相的分布有差异；胆固醇结石患者与色素结石患者相比，泡蛋白的量与促成核活性均增高。通过泡蛋白亲和染色技术，还发现ＣｏｎＡ结合蛋白能与模拟胆汁泡形成脂质－蛋白复合体。作者认为，泡中成核效应蛋白的存在或量与质的改变，在泡凝聚与融合过程中起重要作用。     

Correlation between Cyclin A Gene Expression in Adult Patients with Acute Leukemia and Drug Resistance

Adultacuteleukemia (AL)isoneofthemostcommonmalignanttumorsofhematology .Withtherecentprogressinchemotherapyandsupportivether apy ,theremissionandsurvivalrateinALhavebeenmarkedlyimproved .However ,drugresistanceandrelapsearestillimportantfactorsaffectinglongsur vivalofthese patients .Theabnormalregulationofcellcycleisanotherfactorthatcannotbeignoredex ceptformultipledrugresistance (MDR) .WedetectcyclinA ,multidrugresistantgene (mdrl) ,topoiso meraseⅡα(TopⅡα)andbcl 2inadultpatientswithA…     

Application of a 3D volume 19FMR imaging protocol for mapping oxygen tension (pO2) in perfluorocarbons at low field

A limited flip angle gradient-echo 3D volume acquisition imaging protocol for mapping partial pressure of oxygen (pO₂) in perfluorocarbon compounds (PFCs) at low field (0.14 T) is presented. The pO₂ measurement method is based on the paramagnetic effect of dissolved molecular oxygen (O₂) which reduces the PFC ¹⁹F T_1? Specific objectives related to imaging of PFCs through use of the protocol include improved image signal-to-noise characteristics and elimination of ¹⁹F chemical shift artifacts. A parametric Wiener deconvolution filtering algorithm is used for suppression of ¹⁹F chemical shift artifacts. Application of the protocol is illustrated in a series of calculated pO₂ maps of a gas equilibrated, multi-chamber phantom containing perfluorotributylamine (FC-43). The utility of the protocol is demonstrated in vivo through images of a commercially available perfluorocarbon based blood substitute emulsion containing FC-43 sequestered in the liver and spleen of a rat.     

B超,CT与DSA对肝癌介入治疗的指导价值

对１２６列原发性肝癌与３７例转移性肝癌介入治疗前均进行了Ｂ超、ＣＴ与数字减影血管造影（ＤＳＡ）检查。ＤＳＡ显示原发性肝癌多数血供丰富，而转移性肝癌以少血供者为主；ＣＴ显示小病灶的敏感性稍差，病灶的密度和均匀性与血供多少有一定关系，但特异性不高，而病灶的增强次应与血供关系密切，多血供者中９５％有显示的增强效应，少血供者仅占４．７％；Ｂ超所示病灶的回声高低与血供亦有一定关系，但特异性稍差。结果表明，Ｄ     

扩大经蝶入路进入海绵窦内侧腔的应用显微解剖

目的为临床开展扩大经蝶入路进入海绵窦内侧腔手术提供解剖学依据。方法用50例成人头颅标本．在显微镜下对蝶窦外侧壁、蝶鞍、海绵窦及周围结构进行解剖学观察并测量。模拟扩大经蝶入路磨除海绵窦腹侧骨质，切开海绵窦内侧壁，显露海绵窦内侧腔。结果颈内动脉（ICA）明显隆起于蝶窦侧壁的占58％，蝶窦内隆起呈管型占3％。鞍底硬膜分为2层，海绵窦内侧壁的上部南垂体硬膜构成，无骨性结构支撑；下部由骨周硬膜构成，有蝶窦侧壁骨质支撑。两侧海绵窦内侧壁的距离为（14．8±2．7）mm。海绵窦内侧腔位于C4段ICA与垂体之间，腔内为丰富的静脉丛，最宽可达7mm，但常因ICA扭曲而闭塞。无颅神经穿越海绵窦内侧腔，ICA是扩大经蝶入路探查海绵窦遇到的第一个主要结构。结论扩大经蝶入路进入海绵窦内侧腔是安全可行的。     

儿童阻塞性睡眠呼吸暂停低通气综合征的治疗

目的探讨儿童阻塞性睡眠呼吸暂停低通气综合征(obstructive sleep apnea hypopnea syndrome，OSAHS)患儿的治疗方法和疗效观察。方法经多道睡眠监测(polysomnography，PSG)确诊的4～12岁OSAHS患儿59例：扁桃体切除和(或)经口内镜(内窥镜，下同)引导下腺样体刮除54例；选择长期正压通气治疗(continue positive airway pressure，CPAP)2例；保守治疗3例。采用儿童OSAHS生活质量调查表(quality of life for children with obstructive sleep apnea 18 items，OSA-18)对患儿进行治疗前后的随访。结果围手术期无术后出血、急性呼吸道梗阻发生。随访12～18个月，手术患儿无鼻咽闭锁、咽鼓管功能障碍、腺样体残留等并发症；OSA-18调查评分显示：治疗后76．3％(45例)的患儿生活质量总体指标，88．1％(52例)的患儿睡眠呼吸障碍，67．8％(40例)的患儿身体症状得到显著改善。长期CPAP治疗的有效治疗压力在5．6～7．8cm H2O左右。3例保守治疗者略有改善。结论手术切除引起上气道阻塞的肥大的扁桃体和(或)腺样体是儿童OSAHS有效的治疗手段之一，纤维鼻咽镜检查、头颅侧位X线摄片有助于手术适应证的确定。经口内镜引导下腺样体刮除术具有直视下操作，视野清晰，切除彻底，可避免损伤周围重要结构的特点。