磷酸化肌球蛋白轻链及其激酶在耐药颞叶癫(癎)患者脑组织中的表达

目的探讨耐药性癫癎颞叶和海马脑组织中磷酸化肌球蛋白轻链(phosphorylation of myosin light chain,P-MLC)及其激酶(myosin light chain kinase,MLCK)的表达在癫癎芽生形成中的作用。方法免疫组化检测32例耐药性颞叶癫癎中P-MLC及其激酶MLCK的蛋白质表达水平,并与对照组比较。结果P-MLC免疫组化结果显示,耐药性颞叶癫癎组颞叶光密度值(0.35±0.13)高于对照组(0.19±0.027,P<0.05);耐药组海马光密度值(0.41±0.02)高于对照组(0.10±0.06,P<0.05)。免疫组化结果显示耐药组的MLCK表达水平在颞叶组织和海马组织中较对照组无统计学差异(P>0.05)。结论P-MLC及其激酶MLCK的功能与苔藓纤维芽生关系密切,P-MLC蛋白质产物在耐药性癫中明显升高,但其磷酸化激酶MLCK的表达并不升高,提示MLCK和去磷酸化酶间动态平衡被打破是P-MLC升高的原因,而P-MLC的升高可能在苔藓纤维芽生的形成中发挥重要作用。     

珠海市横琴岛嗜人按蚊生态习性研究

目的:研究珠海市横琴岛嗜人按蚊的生态习性。方法:蚊媒调查方法。结果:横琴岛嗜人按蚊主要孳生于水质清凉、遮阴良好的淡水沟溪及有丰富水体的香蕉地和甘蔗地等。属人、牛血兼吸品种，趋吸人血比例为76、34％，吸血后外逸比例为92、77％，夜间吸血活动高峰在午夜后至次日清晨，全年高峰季节在8～10月。结论:该地嗜人按蚊有人、牛血兼吸，趋吸人血比例较大陆品种低，偏野栖，夜间吸血活动持续时间长，全年活动高峰季节长的生态特点。     

前路减压Z-plate内固定治疗胸腰段爆裂性骨折伴不全性截瘫

目的 探讨胸腰段爆裂性骨折伴不全瘫前路减压内固定优越性以及Z-plate系统的优点。方法 采用前路减压Z-plate内固定治疗胸腰段爆裂性骨折伴不全瘫25例。结果 全部病例均获随访，随访时间6～24个月，平均17个月。按Frankel分级评定有1～3级恢复，随访期间无后凸加重及内固定松动，植骨融合。结论 前路减压Z-plate内固定是治疗胸腰段爆裂性骨折的较好方法。     

羟基磷灰石义眼台暴露的处理和预防

目的：修复较大范围的羟基磷灰石义眼台暴露。方法：将异体巩膜覆盖于义眼台表面，然后严密缝合球筋膜与球结膜，共治疗20例患者。结果：19例修复成功，1例未成功而取出义眼台。结论：应用异体巩膜修复义眼台暴露是有效的。     

长、短链探针以链延伸反应提高基因传感器检测MRSA灵敏度的实验研究

目的：利用链延伸反应的原理延长引物链以提高石英谐振式基因传感器表面的质量负载，从而提高传感器检测MRSA的灵敏度。方法：以不对称PCR的反应产物做为长链探针，人工合成的寡核苷酸片段为短链探针，在基因传感器阵列表面分别固定上金黄色葡萄球菌mecA和femA的长链及短链探针共4种探针片段，与相应的靶序列杂交后，加入Klenow酶，37℃进行链延伸反应1h。结果：长、短链探针均有效地固定了传感器表面。mecA,femA短链探针在链延伸反应前的检测灵敏度为0.5nmol/L，但经链延伸反应后检测灵敏提高到了0.05nmol/L；而长链探针却无法与相应的基因组靶序列发生杂交。结论：短链探针链延伸反应有效地提高了石英谐振式基因传感器的灵敏度，但该法不适用于链探针。     

The effect of 2,4-diamino-6-hydroxy-pyrimidine on postburn Staphylococcus aureus sepsis in rats

GTP-cyclohydrolase I (GTP-CHI) is the first and rate-limiting enzyme for the de novo biosynthesis of biopterin. The present study was to observe the effect of 2,4-diamino-6-hydroxy-pyrimidine (DAHP),an inhibtor of GTP-CHI, on the development of postburn Staphylococcus aureus sepsis. Methods: 56 male Wistar rats were randomly divided into four groups as follows: normal control group (n= 10), scald control group(n= 10),pos tburn sepsis group (n= 20) and DA HP treatment group (n= 16). In the scald control group, rats were subjected to a 20% total body surface area (TBSA) Ⅲ° scald injury, then sacrificed at 24 hrs. In the postburn sepsis group (n=20), rats were inflicted with 20% TBSA Ⅲ° scald followed by Staphylococcus aureus challenge, and they were further divided into 2 and 6 hrs groups. In the DAHP treatment group (n= 16), animals were intraperitoneally injected with a dose of 1g/kg DAHP prior to Staphylococcus aureus challenge, and then further divided into 2, 6 hrs groups. Tissue samples from liver, kidneys, lungs and heart were collected to determine GTP-CHI, inducible nitric oxide synthase (iNOS) and tumor necrosis factor-α (TNF-α) mRNA expression. Meanwhile, biopterin and nitric oxide (NO) levels in these tissues were also measured. Results: After the scald injury followed by Staphylococcus aureus challenge, GTP-CHI mRNA expression and biopterin levels significantly elevated in various tissues such as liver, heart, kidneys and lungs, so did the values of iNOS mRNA expression and NO formation (P＜0.01). Pretreatment with DAHP could significantly reduce GTP-CHI/biopterin induction (P＜0. 05～0. 01), and the up-regulation of iNOS/NO was also suppressed. Furthermore, DAHP administration could also inhibit the gene expression of TNF-α. 2 hrs after septic challenge, TNF-α mRNA expression in liver, kidneys and lungs in DAHP-treated group were 35.7%, 37.3% and 33.0% of those in postburn septic group, respectively. Additionally, in animals without DAHP treatment, the 6-hour mortality was 55.6% (20/36), while it was only 25.0% in DAHP-treated animals (4/16, P=0. 08). Conclusions: Early treatment with DAHP might be a potential strategy to prevent the development of postburn Staphylococcal sepsis, which appears to be associated with down-regulation of biopterin and NO formation by DAHP.     

皮肤光老化皱纹形成机制及维A酸类药物的拮抗作用

日光中长波紫外线 (UVA)长期反复照射是户外工作者暴露部位皮肤光老化及相关皮肤肿瘤多发的重要因素 ,皱纹形成是皮肤光老化的最重要特征 ,研究其作用机制对紫外线辐射损伤的防护有重要意义。基质金属蛋白酶 (matrixmetal loproteinases,MMPs)家族在各种生理、病理条件下细胞外基质降解和重塑中起着关键作用。我们研究了皮肤光老化皱纹形成与真皮成纤维细胞MMPs及MMPs组织抑制剂 (tissueinhibitorofmatrixmetallo proteinases,TIMPs)表达的关系 ,并同时观察了维A酸类药物的拮抗作用。一、材料与方法1 真皮成纤维细胞培养 :标本为健康…     

关于课堂多媒体教学的思考

多媒体教学已成为课堂教学的一种常用手段，多媒体教学应从实际需要出发，以提高教学效果为目标；需要教师掌握多种计算机及多媒体知识技能，科学地进行教学设计；教学过程中应发挥多媒体的优势，注重师生交流。对此本文进行了探讨。     

大鼠自体平滑肌细胞移植对心肌梗死后心功能恢复的作用

目的:研究自体平滑肌细胞移植到心肌梗死区后对心功能恢复的作用.方法:用酶消化法从SD大鼠的输精管中分离、提取自体平滑肌细胞,进行体外培养、扩增.移植组(n=12)将BrdU标记后的自体平滑肌细胞直接注射移植到左冠脉前降支结扎后2周形成的心肌梗死区瘢痕组织中;对照组(n=12)注射同等剂量的DMEM培养液.超声检查评估移植前和移植后4周的心功能状况.用免疫组化染色的方法,检测心肌瘢痕组织中是否有植入的平滑肌细胞存活以及促血管新生的情况.结果:移植的自体平滑肌细胞能在心肌梗死区内存活并形成肌样组织.与对照组比较,移植组左心室舒张末容积(LVEDV)明显减小[(0.78±0.16) vs (0.92±0.15) ml, P<0.01],左心室射血分数(LVEF)显著提高[(47.6±7.2)％ vs (29.3±6.1)％, P<0.01],心肌瘢痕组织血管新生明显[血管密度:(1.9±0.4)/(0.8 mm2) vs (0.4±0.2)/(0.8 mm2), P<0.01].结论:自体平滑肌细胞移植能防止心肌梗死后的心室腔扩大,促进梗死区血管新生,改善心功能.