虚拟现实技术在枢椎椎弓根螺钉精确植入中的应用研究

目的探索以虚拟现实技术为基础的枢椎椎弓根螺钉置人方法。方法选取8具成人颅一颈椎标本，采用改良四柱式定位框架固定于枕颈，使颅-颈-肩形成统一刚体，保持空间位置恒定，CT薄层扫描获取枢椎三维定位信息，采用Aero—Tech立体定向手术规划系统三维建模，设计安全、可视化、个体化的虚拟置钉路径，反复虚拟演示验证钉道安全后，导向弓把持下置人导向钢针，复查CT评价置钉的准确性。结果16个枢椎椎弓根置钉过程中，方向出现偏差（横突孔突破）1个，失败率为6．25％。结论目标椎弓根的容积三维重建、置钉路径可视化设计和虚拟演示，使操作过程简单、直观而精确，不需要线形和角性参数的测量；加上导向抓持装置提供的稳定性，使该技术具有很好的临床应用前景。     

血半胱氨酸蛋白酶抑制剂C水平对急性脑血管病患者早期肾损害的诊断价值

目的探讨急性脑血管病患者早期肾损害的机制及早期监测指标。方法对194例急性脑血管病患者(包括脑梗死129例,脑出血65例)及60例正常对照者同时测定血半胱氨酸蛋白酶抑制剂C(Cys-C)和血肌酐(SCr)浓度,对其中血Cys-c浓度增高但SCr浓度正常的48例急性脑血管病肾早期损害患者用甘露醇治疗,并检测治疗前后血Cys-c浓度。结果在早期肾损害组,血Cys-c浓度明显高于对照组(P<0.001),而SCr浓度2组无显著性差异(P>0.05)。48例急性脑血管病肾早期损害者经甘露醇治疗后,血Cys-c浓度较治疗前明显降低(P<0.001)。结论血清Cys-c测定有助于早期发现肾功能损害,治疗脑血管病的同时应注意监测肾功能。     

老年高血脂患者Apo C检测的临床意义

目的探讨老年高血脂患者血清载脂蛋白CⅡ、CⅢ(Apo CⅡ、CⅢ)的变化及意义.方法免疫比浊法测定老年不同高血脂组血清Apo CⅡ、Apo C Ⅲ水平,并分析与其他指标的相关性.结果老年高血脂患者血清Tch、LDL水平各组间无差异(P＞0.05),且与TG浓度无明显相关; TG浓度与HDL水平呈负相关关系(r=0.435,P＜0.001),与Apo CⅡ、Apo CⅢ水平呈正相关关系(r=0.478,0.426,P＜0.001):老年高血脂患者血清Apo C Ⅱ、Apo CⅢ水平在男女性别间无显著性差异(P＞0.05).结论血清Apo CⅡ、Apo CⅢ水平与动脉粥样硬化危险因子TG呈正相关,提示其在老年人心血管疾病的发生中起一定的作用.     

转TrkC基因神经干细胞移植对脊髓损伤的治疗作用

目的 研究转酪氨酸激酶C（tyrosine kinase C，TrkC）基因神经干细胞（neural stem cells，NSCs）移植治疗脊髓损伤的作用。方法 60只SD大鼠随机分成正常对照组（A组）、脊髓半切组（B组）、NSCs移植组（C组）、NSCs移植＋神经营养素（NT）-3局部使用（D）组、转TrkC基WNSCs移植组（E组）和转TrkC基因NSCs移植＋NT-3局部使用组（F组），每组10只。脊髓损伤后第9天进行细胞移植。各组大鼠在细胞移植后2个月，行体感诱发电位（SEP）和运动诱发电位（MEP）检查以及脊髓运动功能（BBB）评分。结果 细胞移植后2个月SEP和MEP发生潜伏期和峰峰波幅以及右后肢BBB评分的恢复均以下组最佳，与其他各组比较，差异有统计学意义（P＜ 0．05，0．01）。结论在局部给予的NT-3作用下，转TrkC基因NSCs能较好地促进损伤脊髓功能的恢复。     

大剂量Vit C与泼尼松对特发性血小板减少性紫癜疗效的比较

特发性血小板减少性紫癜(ITP)的治疗一般以泼尼松,近来有报道采用大剂量Vit C治疗均可获得较疗效,为了比较两种药物对ITP的疗效及不良反应将我院近年来38例ITP采用此药分组对比结果现报告如下. 　　……     

In vivo kinetics and displacement study of a carbon-11-labeled hallucinogen,N,N-[11C]dimethyltryptamine

The endogenous hallucinogen, N,N-dimethyltryptamine (DMT), was labeled with carbon-11 and its regional distribution in rat brain studied. [¹¹C]DMT showed higher accumulation in the cerebral cortex, caudate putamen, and amygdaloid nuclei. Studies of the subcellular distribution of [¹¹C]DMT revealed the specific localization in the fractions enriched with serotonin receptors only when a very low dose was injected into rats. The proportions of the radioactivity in receptor-rich fractions were greatly enhanced by pretreatment with the monoamine oxidase inhibitor, pargyline. Specific binding of [¹¹C]DMT to serotonin receptors in dog brain was demonstrated by a positron emission tomographic study in which 5-methoxy-N,N-dimethyltryptamine caused approximately 20% displacement of the radioligand from the receptors.     

Inhibition of NMDA-induced protein kinase C translocation by a Zn chelator: Implication of intracellular Zn

The role of intracellular Zn²⁺ in the translocation of protein kinase C from cytosol to membrane fractions was examined by the [³H]phorbol 12,13-dibutyrate (PDBu) binding method in guinea pig cerebral synaptoneurosomes. N-methyl-d-aspartate (NMDA, 100 μM) and calcium ionophore A23187 (0.3–30 μM) decreased the binding activity in the cytosol with a concomitant increase in the membrane fractions. Pretreatment of synaptoneurosomes with a heavy metal chelator, N,N,N′,N′-tetrakis-(2-pyridylmethyl)ethylenediamine (TPEN), inhibited the NMDA- and A23187-induced changes of the distribution of [³H]PDBu binding sites in cytosol and membrane fractions. The inhibitory effect of TPEN was negated by a preincubation of TPEN with equimolar Zn²⁺ but not by that with Ca²⁺. The addition of 500 μM Zn²⁺ to the lysate of synaptoneurosomes induced an increase of [³H]PDBu binding activity in the membrane fraction with a concomitant decrease in the cytosol fraction, as did 100 μM Ca²⁺. Low concentrations of Zn²⁺ (10 μM), which alone had no effect on the distribution of the binding, significantly enhanced the effect of 10 μM Ca²⁺ in the lysate. Under those conditions TPEN inhibited the Zn²⁺-potentiated Ca²⁺-dependent changes in the binding. These results suggest that intracellular Zn²⁺ is essential for the agonist-induced translocation of protein kinase C in guinea pig synaptoneurosomes.     

瘦素、C-反应蛋白与老年急性冠脉综合征患者的相关研究

目的探讨急性冠脉综合征(ACS)患者血浆瘦素(LP)及C-反应蛋白(CRP)水平的变化及其临床意义。方法测定急性心肌梗死组(AMI组)、不稳定型心绞痛组(UA组)、对照组(健康体检者)血浆LP及CRP浓度,分析LP、CRP与病情严重程度的关系以及LP与CRP的相关性。结果AMI组、UA组患者血浆LP、CRP浓度较对照组显著升高(P<0.01),2组患者血浆LP与CRP浓度之间均呈显著正相关;AMI组血浆LP、CRP浓度比UA组明显升高(P<0.05)。结论血浆LP及CRP浓度与ACS病情严重性呈正相关,且LP与CRP浓度呈正相关。说明LP与CRP共同参与组织炎症反应,是ACS重要的危险因素及预测因子。     

Preparation of protected peptidyl thioester intermediates for native chemical ligation by Nα‐9‐fluorenylmethoxycarbonyl (Fmoc) chemistry: considerations of side‐chain and backbone anchoring strategies,and compatible protection for N‐terminal cysteine*,†

Abstract: Native chemical ligation has proven to be a powerful method for the synthesis of small proteins and the semisynthesis of larger ones. The essential synthetic intermediates, which are C‐terminal peptide thioesters, cannot survive the repetitive piperidine deprotection steps of N^α‐9‐fluorenylmethoxycarbonyl (Fmoc) chemistry. Therefore, peptide scientists who prefer to not use N^α‐t‐butyloxycarbonyl (Boc) chemistry need to adopt more esoteric strategies and tactics in order to integrate ligation approaches with Fmoc chemistry. In the present work, side‐chain and backbone anchoring strategies have been used to prepare the required suitably (partially) protected and/or activated peptide intermediates spanning the length of bovine pancreatic trypsin inhibitor (BPTI). Three separate strategies for managing the critical N‐terminal cysteine residue have been developed: (i) incorporation of N^α‐9‐fluorenylmethoxycarbonyl‐S‐(N‐methyl‐N‐phenylcarbamoyl)sulfenylcysteine [Fmoc‐Cys(Snm)‐OH], allowing creation of an otherwise fully protected resin‐bound intermediate with N‐terminal free Cys; (ii) incorporation of N^α‐9‐fluorenylmethoxycarbonyl‐S‐triphenylmethylcysteine [Fmoc‐Cys(Trt)‐OH], generating a stable Fmoc‐Cys(H)‐peptide upon acidolytic cleavage; and (iii) incorporation of N^α‐t‐butyloxycarbonyl‐S‐fluorenylmethylcysteine [Boc‐Cys(Fm)‐OH], generating a stable H‐Cys(Fm)‐peptide upon cleavage. In separate stages of these strategies, thioesters are established at the C‐termini by selective deprotection and coupling steps carried out while peptides remain bound to the supports. Pilot native chemical ligations were pursued directly on‐resin, as well as in solution after cleavage/purification.