Mass spectrometric analysis of the structure of gamma II bovine lens crystallin.

The amino acid sequence of bovine gamma II-crystallin has been verified by a combination of electrospray and fast atom bombardment mass spectrometry. The molecular weight of gamma II, isolated by gel filtration and ion exchange chromatography, was determined to be 20,967 +/- 3 by electrospray mass spectrometry. Another aliquot of gamma II was completely digested by trypsin in a medium of 20% CH3CN and 0.1 M Tris, pH 8.2. The tryptic peptides were separated by reversed phase HPLC and identified by their molecular weights, as determined by fast atom bombardment mass spectrometry (FABMS). The identification of each peptide was confirmed by digesting the peptide further to give new peptides whose molecular weights were also determined by FABMS and related to the proposed amino acid sequences. The data from both types of mass spectrometric analyses were consistent with the sequence previously proposed by Hay et al. (J. Biol. Chem. 1987, 146, 332-338), including threonine at position 119. The FAB mass spectrum of one HPLC fraction suggested that disulfide bonding between Cys 18 and Cys 22 was present in at least half the protein preparation. Whether the Cys 18/Cys 22 disulfide bond was present in native gamma II or was produced during isolation or enzymic digestion could not be determined from these studies. Samples that had been stored for several weeks showed that several of the cysteines had become disulfide bonded. These studies illustrate the power of mass spectrometric techniques to accurately confirm the primary structure of proteins and to identify post-translational modifications.     

^60Co消毒与高温高压消毒胚胎骨的实验研究

在12只健康家兔下颌骨体部的两侧各造成0.7cm×0.5cm×0.3cm的骨缺损区，分别置入^60Co消毒的胚胎骨和高温高压消毒的胚胎骨，发现高温高压消毒可以替代^60Co消毒胚胎骨进行移植，为临床提供了一种新的用作同种异体移植胚胎骨的消毒方法。     

血清白细胞介素－2受体的测定在脑血管性痴呆诊治中意义的探讨

目的 :检测脑血管性痴呆患者血清中可溶性白细胞介素 - 2 (s IL- 2 R)水平 ,评价 s IL- 2 R的测定在诊治脑血管性痴呆中的价值。方法 :采用双抗体夹心的 EL ISA法检测脑血管性痴呆患者血清中 s IL- 2 R的水平。结果 :脑血管性痴呆患者血清中的 s IL- 2 R水平较健康对照组显著增高 ,两组比较差异非常显著 (P <0 .0 1)。结论 :检测脑血管性痴呆患者血清中 s IL- 2 R水平 ,有助于了解患者的免疫功能变化及疗效观察     

腰椎间盘突出症手术后复发的原因分析及防治

目的 分析总结腰椎间盘突出症手术后复发的原因及治疗方法。方法 腰椎间盘突出症手术后复发的范围限定于临床症状、体征及影像学证实为受累神经根与第一次手术的节段相同。回顾1990年～2001年收治的资料完整的病例38例。总结造成复发的原因，分析造成这些原因的因素以及防范措施，并提出治疗方案。结果 复发的原因为髓核再突出20例(占52．7％)、疤痕压迫5例(占13．1％)、硬脊膜及神经根四周粘连5例(占13．1％)、腰椎失稳4例(占l0．5％)、神经根管、侧隐窝狭窄4例(占l0．5％)，其中经保守治疗和手术治疗分别为2l例(占55．3％)和17例(占47．7％),治疗优良率92％。结论 腰椎间盘突出症术后复发的主要原因为髓核再突出。复发后经中西医结合治疗能取得满意疗效,治疗上首先应采用保守治疗。     

重症溃疡性结肠炎的诊断、评估与治疗

近年来,溃疡性结肠炎(ulcerative colitis,UC)已成为我国消化系统常见疾病和慢性腹泻的主要病因。全国20余家大型医院回顾性研究发现,UC住院病例逐年增多,其中重症病例占21.7%,并发症又占其中60%,危重病例相应增多,值得临床医师重视。重症溃疡性结肠炎的诊断与评估1.首先根据临     

兔动静脉短路环法诱导组织工程骨支架材料血管生成的初步研究

Objective To compare the effects of 2 vascular carriers, arteriovenous loop and arteri-ovenous bundle, on inducing angiogenesis in coral scaffold of vascularized tissue-engineered bone in animal models.Methods Thirty-six adult male New Zealand rabbits were randomized into 2 even groups.In group A, an arteriovenous loop (AVL) was formed by microsurgical anastomosis at the proximal ends between the femoral poptiteal artery and vein, and placed in the circular side groove of the coral block (6 mm × 8 mm × 10 mm) .In group B, flow-through vessels bundles of both femoral artery and vein were placed in the side grooves of the coral block.All the implants in 2 groups were wrapped by a micro-porous expand-ed-polytetrafluoroethylene (ePTFE) membrane, and fixed subcutaneously by suturing.Evaluation methods included gross morphological observations, histological examinations, India ink perfusion and vascular casting after 2, 4, 6 weeks.The density of blood vessels was analyzed by the statistical software SPSS 10.0.Results All the corals were encased by newly formed fibrovascular tissues in 2 groups.Ink-stained vessels distributed the surfaces and side grooves, and invaded the interspaces of corals.The degree of vascularization increased over the course of experiment.Blood vessel density demonstrated a significant continuous increase between 2 and 6 weeks after implantation in group A.The mean value of blood vessel density in group A (2 weeks 276.60±4.67, 4 weeks 517.20±10.66, 6 weeks 707.00 ±11.87) was significantly higher than in group B (2 weeks 153.60 ±7.16, 4 weeks 269.40±6.80, 6 weeks 279.20±6.53) (P <0.01).Vascular casting showed that in group A, significant blood vessels sprouted from all areas of the loop, espe-cially at the entrance of the arteriovenous pediele where the small tubes were densely interconnected.In group B, however, no blood vessels sprouted from the arteriovenous bundles and only some small vessels grew from the entrance and exit.Conclusions A vascularized coral model can be constructed by inserting an ar-teriovenous loop or an arteriovenous bundle, useful in vascular bone tissue engineering.The former, however, have stronger abilities to induce angiogenesis than the latter.     

403例小儿24小时脑电图监测分析

对４０３例各类反复发作性症状的患儿进行了２４小时脑电图监测，结果表明：临床确诊癫痫组的阳性率为８２．７％，痫样放电最多出现于非快速眼动睡眠期，限局性放电占６９％。可疑癫痫组中经监测７０％以上排除或基本排除痫性发作。认为２４小时脑电图监测在鉴别临床发作性质，确定癫痫分型，研究癫痫与睡眠的关系，临床发作与脑电图的关系等方面具有较大价值。     

自乳化释药系统的体外评价

目的 探讨自乳化释药系统的体外评价方法。方法 通过测定自乳化时间、乳化后乳剂粒径的大小及模型药物的体外溶出行为对自乳化释药系统进行体外评价。结果 优选出的自乳化处方10min内已基本乳化完全，乳化后乳剂粒子大小大多数在3μm左右，以吲哚美辛和尼莫地平为模型药物制备出自乳化释药系统，体外溶出结果表明：与混悬液相比，两种药物的体外溶出显提高。结论 自乳化释药系统能够提高难溶性药物的体外溶出。     

采用修正正交分段线性函数求解时滞系统和卷积的方法

应用修正正交分段线性函数的时滞和反向特性，推导出求解时滞系统和卷积的公式。数字仿真表明，它具有计算简单，精度高的优点。     

Mental stress-induced myocardial ischemia in coronary artery disease patients with left ventricular dysfunction

Background  Reduced left ventricular ejection fraction (LVEF) is a risk factor for poor outcomes in patients with coronary artery disease (CAD). Mental stress-induced myocardial ischemia (MSIMI) also identifies a subset of CAD patients at increased risk for future cardiovascular events. Susceptibility to MSIMI in patients with CAD and reduced LVEF is unknown. Methods and Results  We enrolled 182 patients (67 women) with a mean age of 64 years and a documented history of CAD in this study. Baseline resting ejection fraction was determined by use of technetium 99m sestamibi gated single photon emission computed tomography. Abnormal LVEF was defined as less than 45% for men and less than 50% for women (based on published norms for our software [Cedars-Sinai Medical Center]). All participants underwent mental stress testing with a public speaking task. Rest/stress myocardial perfusion single photon emission computed tomography was performed via conventional methodology. Images were visually compared for number and severity of perfusion defects by use of a scoring method from 0 to 4. A summed difference score was calculated as the difference between summed stress and rest scores. A score of greater than 3 was considered abnormal. MSIMI developed in 19% of patients with normal LVEF and 31% of those with reduced LVEF. There is no statistically significant difference between the two groups (P=.11). Conclusions  CAD patients with left ventricular dysfunction are equally susceptible to MSIMI as those with normal LVEF. This study was supported by grants HL 070265 and HL 072059 from the National Heart. Lung, and Blood Institute. This material is also the result of work supported by resources and with the use of facilities at the Department of Veterans. Affairs Medical Center, Gainesville, Fla.