头孢替唑钠与头孢哌酮治疗小儿急性细菌性下呼吸道感染的临床疗效比较

目的:评价头孢替唑钠治疗小儿急性细菌性下呼吸道感染的临床有效性、安全性。方法:轻、中度急性细菌性下呼吸道感染患儿115例分成2组,头孢替唑组58例,予头孢替唑钠20～80mg/(kg·d),溶于10%葡萄糖溶液中,分2次静脉滴注。头孢哌酮组57例,予头孢哌酮50～150mg/(kg·d),分二次静脉滴注。两组均以7~10d为一疗程。结果:头孢替唑钠组与头孢哌酮组的临床有效率分别为93%与91%(P>0.05),细菌清除率分别为92%与89%(P>0.05)。两组均无明显的不良反应。结论:头孢替唑可作为治疗小儿轻、中度急性细菌性下呼吸道感染有效和安全的抗生素。     

一种新型人TNFα对人肝癌裸鼠移植瘤的抗瘤作用

用人肝癌Ｂｅｌ７４０２瘤株建立了人肝癌裸鼠移植瘤模型，探讨新型重组人ＴＮＦａ对这种移植瘤的抗瘤作用，结果表明，ｒｈＴＦａＤ１１ａ和原型重组人ＴＮＦａ的抑瘤率在３０％左右时，后者后用的活性产闰数是前者的２倍；两者用量相同时，前者的抑产经比后者提高２３个百分     

Phase-derivative analysis in MR angiography: Reduced Venc dependency and improved vessel wall detection in laminar and disturbed flow

A problem of current MRA techniques is the inability to accurately depict the vascular anatomy, particularly in areas of disturbed flow. Various reasons, such as intravoxel phase dispersion, saturation, temporal variations, and maximum intensity projection (MIP) nonlinearity, cause a wrong delineation of vessel boundaries. A phase contrast (PC)-based postprocessing operation, the phase derivative (PhD), is introduced to detect phase fluctuations indicating flow. Two-dimensional and three-dimensional angiographic reconstruction algorithms are presented. Mathematical formulas are derived to predict the effect of sampling to flow profiles and the effect on the PhD of these profiles. Numerical, phantom, and preliminary in vivo experiments demonstrate that PhD images do not suffer from phase wraps and allow a velocity dynamic range extension only limited by a differential phase change. It is also shown that PhD MIPs produce higher signal-to-noise ratios than conventional PC angiograms and give a better impression of the anatomy of (stenotic) vessels and of their diameters for both laminar and disturbed flow.     

CT仿真结肠内窥镜的临床应用研究

目的:研究CT仿真结肠内窥镜(CT Virtual Colonoscopy,CTVC)的使用价值,应用方法及镜下表现。方法:使用Hispeed FX/i扫描机,扫描层厚3～5mm,螺距1～2,重叠重建率50％～67％。利用Navigator Smooth软件对容积扫描数据进行三维重建,获得仿真结肠内窥镜的影像,并与纤维肠镜和/或手术所见对照分析,全部病例经病理证实。结果:通过选择不同的观察方位,角度和阈值,CTVC能清楚显示靶器官内正常解剖结构的立体影像和病变的部位、大小、形态及其侵犯范围。CTVC对结肠病变形态的显示与FC或/和标本显示具有良好的对应性,另外,CTVC能从闭塞和狭窄的远端观察病变。但CTVC不能显示组织的颜色变化,不能活检。结论:CTVC作为一种新的非侵袭性结肠检查方法,可以作为纤维结肠镜的有效补充手段,有较好的临床应用价值。     

Vessel enhancement filtering in three-dimensional MR angiograms using long-range signal correlation

Small vessels in three-dimensional MR angiograms have low visibility in maximum-intensity projection images because of their low contrast. In a previous study, we had two nonlinear filters that appeared to give significant improvement in small vessel detail. In this paper, we report on a generalization of this filter that allows a more general modeling of the vessels and a more complete suppression of background. One implementation of the general filter gave a vessel mean contrast-to-noise ratio that is 2.52 and 3.51 times higher than the vessel mean contrast-to-noise ratio obtained using our previously reported maximum-minimum (max-min) filter and cross- section filter, respectively.     

改进虎杖、鸡血藤炮制方法的研究

对虎杖、鸡血藤作了切制、干燥时间和成品、主要成分及水浸出物的比较。结果表明,趁鲜切片优于传统切块、再切片,既能提高饮片的规格质量和成分含量,亦能减少重复劳动,节约能源,避免药材的浪费。     

In vivo comparison of two through-plane MR velocity mapping methods: Fast fourier encoding and phase mapping

Magnetic resonance imaging maps of velocity were acquired with a 1.5-T system in 10 subjects in a plane perpendicular to the main pulmonary artery. Velocity images were successively acquired with a method developed from Fourier-encoding velocity imaging (FEVI) principles with eight gradient steps and one excitation, and with two-point phase-subtraction mapping. Reconstruction in FEVI was implemented by zero-filling interpolation around the eight gradient steps and then around the four central steps. The methods were compared by using estimates of noise in velocity measurements based on the difference between the experimental map and a smooth fitted map. For the same acquisition time, FEVI with four encoding steps was more precise in velocity measurements than phase mapping. Precision was further increased by the use of eight encoding steps, but acquisition time was doubled.     

腹部CTA检查的质量保证

目的:探讨螺旋CT血管造影(Spiral CT angiography,SCTA)技术,以期提高SCTA造影的质量。材料与方法:采用Somatom Plus 4螺旋CT扫描系统对10例病人行腹部SCTA检查。扫描技术和造影剂参数按病变范围和性质而定,三维重建采用最大强度投影法(MIP)或表面阴影显示法(SSD)或弯曲平面重建法(CPR)。结果:SCTA检查技术能可靠地显示血管形态和病变,评价腹部肿瘤与邻近血管关系。结论:SCTA是无创伤性的血管成像术,在很大范围可替代创伤性的血管造影。     

几种咪唑类外用抗真菌药接触性皮炎的初步研究

用３种常用外用咪唑类抗真菌药，达克宁霜（咪康唑）、联苯苄唑霜及癣敌软膏（益康唑）对１８５例有外用此类药物史的皮肤病病人进行了斑贴试验。结果斑试刺激反应及过敏反应阳性率分别为３．８％及４．３％，说明此类药物是常见的致敏原及刺激原之一。抗真菌剂致敏可出现急性接触性皮炎，应与真菌病加重相鉴别。斑贴试验可以诊断抗真菌剂接触性皮炎，并区分刺激反应与过敏反应。     

Dopamine receptor agonists alter gap prestimulus modulation

An innocuous sensory event (a prestimulus) that briefly precedes a startle-eliciting stimulus (SES) will reduce the amplitude of the subsequently elicited reflex. In three experiments brief silent periods in otherwise continuous noise (gaps) were used as prestimuli to investigate the effects of the D₁ dopamine receptor agonist (±)-SKF-38393 (SKF) and the dopamine D₂ receptor group agonist (−)-quinpirole hydrochloride on gap inhibition of the rat’s acoustic startle reflex. Gap durations of 4 and 50 ms were analyzed. Quinpirole (0–1.6 mg/kg) had a biphasic effect on gap inhibition. Lower doses increased gap inhibition, an effect that peaked at the 0.4 mg/kg dose. For higher doses, inhibition returned to control levels for the 4-ms long gap, but remained elevated for the 50-ms long gap. SKF had no effect on gap inhibition, and haloperidol (0.2 mg/kg) reversed the quinpirole-induced increase of gap inhibition. These data implicate the D₂ dopamine receptor group in gap inhibition of startle modulation. The results are discussed in terms of the effects of catecholamine agonists on attention. Received: 25 July 1995/Final version: 28 April 1997