双层滑动型接骨板的生物力不分析与临床应用

临床实践证明双层滑动型接骨板治疗四肢长骨骨折是疗效较好的内固定方法。本文从生物力学角度对24具湿润新鲜尸体股骨进行力学试验。测定了骨折固定部位的应力、应变、位移的分布，证明了这种固定方法是符合生物力学原理的，从载荷、应力、位移等一系列曲线表明它的松动、移位，钉板断裂很少发生，它能促进新骨生长和加速骨折愈合。     

家蚕内网虫属微孢虫核糖体小亚单位RNA(SSUrRNA)核心序列的克隆和序列分析

Endoreticulatus bombycis is a new pathogenic microspordia isolated from the silkworm larvae.With polymerase chain reaction(PCR) method,we amplified a fragment of the core sequence of the small subunit ribosomal RNA( SSUr-RNA) of Endoreticulatus bombycis.The SSUrRNA fragment was inserted into pMD18-T Vector and then cloned.It had a length of 1230 nucleotides and a percentage GC content of 51.3%.The accession number in Genbank is gill 181769|AY009115.The secondary structure model of the SSUrRNA of Endoreticulatus bombycis was constructed both on the bases of the sequence alignment and RNAFOLD program of the PC-GENE package.The secondary structure model revealed that Endoreticulatus bombycis lacked many cukaryotic hclices.such as heli10,helix 11.helix 18,helix 43 and helix 46,but it has V4 region and has more of prokaryotic character.Analyzed by Blast,Endoreticulatus bombycis.Endoreticulatus schubergi and pleistophora sp.(Sd-Nu-IW8201) have a high similarity,over 98%,Phylogeny tree of Endoreticulatus and Pleistophora species showed that Endoreticulatus and Pleistophora sp.(Sd0Nu-IW8201) was in a group and the other Pleistophora species were in another group[Acta Zoologica Sinica 49(3):414-420,2001].     

用分子生物学技术对草菇进行菌株鉴别

利用AP-PCR和RAPD技术对三个草菇菌株进行鉴别,其结果与用草菇菌株V34基因文库中的中等重复序列为探针进行限制性内切酶长度多态性分析(RFLP),及对编码核糖体5.8SrRNA的DNA(rDNA)进行PCR扩增后的产物进行限制性内切酶长度多态性分析(PCR-RFLP)的结果相一致。这一结果显示出用这四种方法对草菇菌株进行鉴别具有相似的效果。同时用这四种方法构建的分子生物学标记显示出这三个菌株中的两个菌株在遗传上有着较大程度的相似性。     

枯草杆菌内切葡聚糖酶基因的克隆及表达

以质粒Ｐｕｃ１８为载体,从枯草杆菌（Ｂａｃｉｌｕｓｓｕｂｔｉｌｉｓ）ＤＢ１０４基因组中克隆到一个内切葡聚糖酶基因。限制酶切分析表明重组质粒中的插入片段为３.５ｋｂ,其中各含有一个ＥｃｏＲＩ,ＨｉｎｄⅢ和ＰｖｕⅡ位点。该插入片段含有一完整的内切葡聚糖酶基因,其自身启动子能被大肠杆菌转录系统所识别。当加入ｌａｃＺα基因启动子的诱导物ＩＰＴＧ后,内切葡聚糖酶表达量提高２.８倍。加入０.５％葡萄糖能抑制该基因的表达。该基因在大肠杆菌ＤＨ５αＦ′中表达的内切葡聚糖酶分布为：胞外６７.３％,胞间周质３.９％,胞内２８.８％。Ｓｏｕｔｈｅｒｎ杂交证实了该插入片段来自供体菌Ｂ．ＳｕｂｔｉｌｉｓＤＢ１０４。     

SH－SY5Y细胞胞内钙库特性研究

运用单细胞显微荧光测量技术测量了单个ＳＨ—ＳＹ５Ｙ细胞内游离钙离子浓度的变化。首次报道了ＳＨ—ＳＹ５Ｙ细胞内存在毒蕈碱敏感而非咖啡因敏感的钙库,并研究了它的动力学特征。Ｎ￣￣Ｃ￣ｈｅｔｗＭａｄＵｇｈ＊ＴＯｗｈｏｍＣｂ￣ｐｏｎｄｅｎｅｅｓｈｏｕｌｄｂｅ￣．     

Reversion of malignancy in human gastric cancer MKN—45 cells through the transfection of transforming growth factor—β type Ⅱ receptor gene

Human gastric cancer MKN-45 cells which are resistant to TGF-β growth inhibition and possess TGF-β type I and type Ⅲ receptors,but not type Ⅱ receptors,have been used as a model system to reconstitute these cancer cells with TGF-β RII cDNA.The results of these experiments indicated that the reexpression of TGF-β RII gene in MKN-45 cells can restore their sensitivity to TGF-β growth inhibition,decrease their growth rate,reduce their cloning efficiency in soft agar and tumorigenicity in nude mice in stable transfectants,in comparison with their control MKN-45 cells.Among different RII transfectants,their difference in the changes of these parameters,as a result of the regain of autocrine negative growth control by TGF-β,is roughly proportional to their level of expression of transfected RII mRNA.From these data,it is concluded that the inactivation of TGF-β RII gene is related to the escape of growth control by TGF-β in MKN-45 cells.The importance of the study of the interplay of TGF-β and its receptor system in the negative growth control of gastric cancer,and possibly also of other cancers,is discussed.     

异色瓢虫若虫对麦三叉蚜的捕食作用

研究表明,异色瓢虫高龄若虫捕食麦二叉蚜的功能反应为ＨｏｌｌｉｎｇⅡ型反应,喜好捕食低龄若蚜;在４０℃下捕食率最低,１０℃次之,２５℃最高．在１０～２５℃内捕食率ｙ与温度ｘ的关系为ｙ＝２８．１３０３＋２．６６６５ｘ,在２５～４０℃内为ｙ＝１９９．９２７５－３．６４２ｘ;在种内干扰条件下,其捕食作用率Ｅ与开敌密度Ｐ的关系为Ｅ＝０．６８９７Ｐ－０．７９３０,搜索常数Ｑ为０．６８９７,干扰系数ｍ为０．７９３０;其分摊竞争强度Ｉ与异色瓢虫密度Ｐ的关系为Ｉ＝０．０４００＋１．０３８３ｌｏｇＰ．     

幽门螺旋杆菌感染与胃癌的关系

幽门螺旋杆菌感染与胃癌的关系龙允穗综述陈振侬、洪瑞香审校（广西医科大学一附院内科南宁５３００２７）越来越多的研究证明,幽门螺旋杆菌（Ｈｅ－ｌｉｃｏｂａｃｔｅｒｐｙｏｒｉ,ＨＰ）感染是慢性胃炎,尤其是活动性胃炎的重要病因,且与消化性溃疡发生密切相关［１...     

蛇胆祛痰作用的实验研究

用２组小鼠,每组１０只。实验组用蛇胆酒灌胃,对照组用生理盐水灌胃,均以气管内酚红排泄法观察。结果示,酚红排泄量实验组比对照组明显为高。说明蛇胆确有增加小鼠气管分泌,稀释痰液的作用     

孤啡肽——新发现的内阿片肽及其受体

孤啡肽是最近发现的一个１７肽,其结构与已知的内阿片肽,尤其是强啡肽Ａ类似;但具有明显不同的药理学特性;与经典的阿片受体结合能力很弱,而与阿片受体家族中的一个新成员－－“孤儿受体”结合能力很强,因而认为是该受体的天然配基,孤啡肽脑室注射可使小鼠痛觉过敏,运动减少。孤啡肽受体是阿片受体家族中的新成员,属于Ｇ蛋白偶联受体,与经典的阿片受体配基亲和力均很弱,该受体激活后介导对腺苷酸环化酶活力的抑制。