预酸蚀乳牙牙本质对自酸蚀粘接系统粘接强度的影响

目的:探讨预酸蚀乳牙牙本质对自酸蚀粘接系统粘接强度的影响。方法:随机选取28颗健康乳磨牙,磨除颊舌面釉质,暴露牙本质粘接面,沿近远中向劈开形成56个样本,随机分为7组(n=8)。直接涂布组(A1组,A2组和A3组)分别涂布AdperTM Easy One(AEO),Xeno-V(XV)和OptiBond All In One(AIO)三种自酸蚀粘接剂,预酸蚀组(B1组,B2组和B3组)在涂布三种自酸蚀粘接剂前先使用35%磷酸酸蚀乳牙牙本质15 s,对照组(C组)使用Prime&Bond NTTM(NT)全酸蚀粘接剂,每个样本用Z350复合树脂堆砌成直径为3 mm的树脂小柱,通过剪切试验测试剪切粘接强度,并通过扫描电子显微镜观察断裂表面形态。结果:B1组,B2组的剪切粘接强度值明显高于A1组,A2组(P<0.001);B3组与A3组的剪切粘接强度值比较无明显差别(P=0.94)。A2组的剪切粘接强度值低于C组(P<0.05);B1组的剪切粘接强度值明显高于C组(P<0.001)。扫描电镜观察结果显示各组试件断裂面形态多为牙本质和复合树脂界面破坏。直接涂布组(A1组,A2组和A3组)断裂多发生在混合层的底部,树脂突较少且低于小管口。B1组和B2组试件断裂面可见多数牙本质小管被树脂突填满,断裂多发生在混合层的中上部。B3组试件断裂面可见牙本质小管空虚,树脂突较少。结论:预酸蚀乳牙牙本质可以提高AEO,XV两种自酸蚀粘接剂的剪切粘接强度。自酸蚀粘接剂处理乳牙牙本质可以达到全酸蚀粘接剂处理的粘接强度,但应用自酸蚀粘接剂前预酸蚀乳牙牙本质可以获得更高的粘接强度。     

不同方法处理的纯氧化铝瓷贴面粘接强度的研究

目的:观察喷砂、酸蚀、二氧化硅水溶胶热处理等表面处理方法对纯氧化铝陶瓷贴面与树脂之间粘接强度的影响。方法:选择高纯α-Al2O3烧结的纯氧化铝陶瓷贴面样本30个,将其随机分为A、B、C三组,每组10个。分别应用不同的表面处理方法与同一种树脂进行粘结,A组采用单纯喷砂,B组采用喷砂+二氧化硅表面处理+HF,C组采用喷砂+二氧化硅表面处理+硅烷偶联剂,检测和比较各组的粘接强度。结果:C组的粘接强度最大,为23.84±0.74,明显高于A组和B组(P<0.05),而A组和B组的粘接强度比较差异无统计学意义(P>0.05)。结论:单纯喷砂或二氧化硅水溶胶热处理与HF的联合使用对纯氧化铝陶瓷贴面与树脂之间的粘接强度无明显改善,而采用喷砂以及二氧化硅水溶胶热处理与硅烷偶联剂的联合应用可取得纯氧化铝陶瓷贴面与树脂间的最大粘接效果。     

纳米SiO_2对poss复合树脂弯曲和抗压强度的影响

目的:观察纳米SiO2填料对纳米复合树脂poss的弯曲强度和抗压强度的影响,探究纳米SiO2的最佳添加比。方法:将经过硅烷偶联化的纳米SiO2颗粒加入poss复合树脂中,合成SiO2质量分数分别为0.5%,1%,1.5%和2%的SiO2/poss复合树脂,分别为BCDE四组,纯poss组为A组(对照组)。每组试件固定于万能材料测试机上,以1.0mm/min的速度垂直加压直至试样破坏,采用SPSS16.0软件对结果做单因素方差分析。结果:弯曲强度测试结果:C组最高,与其他四组均有统计学差异(P0.05);A、B、D三组无显著性差异,与E组差异明显(P0.05)。抗压强度测试结果:D组最高,与其他四组均有统计学差异(P0.05);B组和E组与A组差异显著(P0.05),与C组无显著差异。结论:纳米SiO2在一定范围内能够提高poss复合树脂的弯曲强度和抗压强度。     

不同粘接剂在纤维桩修复上前牙残冠残根中的临床疗效比较

目的:比较2种不同的纤维桩粘接剂在桩-核-冠修复方法修复前牙残冠残根的临床疗效.方法:对近2年内的78名96例经过完善根管治疗的上前牙残冠、残根的患者,选用2种不同的粘接材料(3M ESPE RelyX Unicem粘接剂和Panavia F粘接剂)对PD(Produits Dentaires SA)纤维桩进行粘接、3M ESPE Kiltek Z350树脂等材料修复,并经过2年的随访观察,评估2种治疗方法的疗效.结果:经过2年的随访调查发现,96例患牙中仅在半年时出现了1例修复体折断(使用Panavia F粘接法),其余95例均未出现纤维桩的松动、脱落,无根折、桩折现象.结论:纤维桩修复残冠、残根是一种操作简便、省时、临床疗效好的修复方法;3Municem和PanaviaF粘接剂均可以有效防止纤维桩在修复上前牙残冠、残根中的松动、脱落现象,均是有效的粘接手段.     

自粘结树脂水门汀粘结牙本质的超微结构观察

目的：通过扫描电镜比较4种树脂水门汀（RelyX Unicem、PanaviaF、VariolinkⅡ、Vitique）粘结牙本质时超微结构的差异。方法：新鲜拔除的人无龋坏第三磨牙12颗,随机分为4组（n=3）,制备牙本质粘结面,分别与4种树脂水门汀（RelyX Unicem、PanaviaF、VariolinkⅡ、Vitique）粘结处理,将所得粘结试件二次纵切,SEM观察牙本质粘结界面。结果：四种树脂水门汀与牙本质粘结中,RelyXUnicem未见明显树脂突,而PanaviaF、VariolinkⅡ和Vitique均可见明显树脂突形成。结论：新型自粘结树脂水门汀粘结牙本质的超微结构完全有别于传统树脂水门汀。     

Er:YAG激光处理对牙釉质及牙本质修复效果的影响

研究不同表面处理条件下Er:YAG激光照射对牙釉质及牙本质修复效果的影响。80个样本随机分成牙釉质和牙本质2大组,再根据处理方式随机分为4小组:①酸蚀(37%磷酸);②Er:YAG激光;③自酸蚀粘接处理剂;④Er:YAG激光+自酸蚀粘接处理剂。与树脂加强型玻璃离子水门汀(RMGIC)粘接后37℃水浴中储存24 h,用万能测试机测定粘接剪切强度。牙釉质及牙本质组结果均为3、4小组粘结强度接近(P0.05),显著高于其他组(P0.05),1、2小组间粘结强度差别无统计学差异(P0.05)。Er:YAG激光照射可替代37%磷酸酸蚀处理方法;G-Bond自酸蚀粘接处理剂可提高牙面与RMGIC间的粘结力,Er:YAG激光处理不影响该效果。     

运动强度对乳酸浓度、氧化应激、免疫状况的影响研究

为探讨不同强度运动对男性大学生乳酸浓度、氧化应激、免疫状况的影响,本研究选取80名健康男性大学生,采用随机数字表法将学生分为安静组、运动A组、运动B组和运动C组,其中安静组不运动,静坐30 min;运动A组强度为55%VO_(2max),运动15 min×2次,间歇5 min;运动B组强度为70%VO_(2max),运动10 min×3次,间歇5 min;运动C组强度为85%VO_(2max),运动7.5 min×4次,间歇5 min;检测各组运动前后乳酸、氧化应激及免疫指标。结果发现,运动C组运动结束后即刻血清乳酸浓度为(7.89±0.80) mmol/L,明显高于安静组、运动A组和运动B组(p0.05);运动C组运动结束后即刻SOD和MDA分别为(16 011.22±1 532.10) U/gHb和(3.37±0.31) nmol/mL,明显高于安静组、运动A组和运动B组(p0.05);运动B组运动结束后即刻NO为(123.10±11.52) mmol/L,明显高于安静组、运动A组和运动C组(p0.05);运动A组运动结束后即刻NOS为(48.01±3.01) U/mL,明显高于安静组、运动B组和运动C组;运动C组运动结束后即刻CD4为(42.29±0.90)%,明显高于安静组、运动A组和运动B组(p0.05)。本研究说明,运动负荷量对男性大学生血清乳酸、氧化应激和免疫情况有一定影响,在运动训练时应选择合适的运动负荷量,避免对机体带来负面影响。     

DJ-1基因siRNA对三阴性乳腺癌细胞侵袭和迁移影响的研究

目的:探讨DJ-1基因siRNA对三阴性乳腺癌细胞体外侵袭和迁移能力的影响。方法:设计DJ-1基因的小分子干扰RNA(siRNA)片段,脂质体介导转染入三阴性乳腺癌细胞株MAD-MB-23l,转染分3个组:A组(空白对照control组)、B组(转染非特异性对照Scramble组)、C组(转染si DJ-1组)。应用Western blotting免疫印迹法检测转染前后DJ-1表达水平;运用细胞迁移和侵袭实验检测细胞迁移和侵袭能力的变化。结果:C组DJ-1蛋白的表达强度弱于A组和B组(t=9.831,P0.05),而A组与B组比较,DJ-1蛋白表达水平则无明显差异(t=1.629,P0.05)。细胞迁移实验中,A组细胞为(218.37±12.75);B组的细胞为(214.46±11.38);C组的细胞为(129.65±8.59),C组细胞明显少于A组和B组(t=10.927,9.984,P0.05),而A组与B组之间,差异无统计学意义(t=0.512,P0.05)。细胞侵袭实验中,A组细胞为(127.28±12.65);B组的细胞为(123.06±13.08);C组的细胞为(52.85±9.58),C组穿过人工基底膜的细胞明显少于A组和B组(t=7.927,8.643,P0.05),而A组与B组之间,差异无统计学意义(t=0.627,P0.05)。结论:DJ-1基因siRNA可抑制三阴性乳腺癌细胞侵袭和迁移。     

CysC,mALB和尿BGM联合检测在2型糖尿病早期肾损中的临床价值

目的:探讨CysC、mALB和尿BGM联合检测在2型糖尿病早期肾损中的临床价值。方法:选取2010年11月至2013年6月我院内分泌科收治的130名2型糠尿病患者,根据空腹血糖值的不同程度将其分为A、B两组,A组72例,B组58例,另选取同期在我院体检的年龄、性别等资料与之匹配的64名健康者设为C组。分别对其CysC、mALB和尿BGM进行测定,并进行对比分析。结果:通过分析可知,A组和B组的Cys C分别为(3.29±1.09)mg/L、(2.86±1.05)mg/L,相对于C组的(0.87±0.99)mg/L,均明显升高,但A组升高更加明显;A组、B组、C组的mALB分别为(37.36±4.82)mg/L、(36.55±4.31)mg/L、(6.61±3.84)mg/L,B组高于A组,C组高于A组和B组;三组的BGM中,以A组最高,为(634.15±55.24)μg/L,B组其次,为(626.92±48.18)μg/L,均高于C组的(57.12±11.75)μg/L;Cys C、mALB、BGM等阳性指标的检出率分别为76.15%、77.69%、72.31%,而Cys C、mALB、BGM联合检测的检出率为93.85%,明显高于其他单指标检测。且P0.05,差异具有统计学意义。结论:对CysC、mALB和尿BGM进行联合检测对2型糖尿病早期肾损患者具有较高的检出率,相对于单指标检测,敏感性更高。     

不同规格中华绒螯蟹母本子代的生长特性比较

为研究中华绒螯蟹(Eriocheir sinensis)不同规格母本子代的生长发育,本实验在生态池塘中放置网箱养殖中华绒螯蟹,按照母本规格不同设置4个组,组A、B、C和D分别为母本体重(175.7±5.3)g、(150.4±5.8)g、(125.6±5.5)g和(100.2±5.9)g的子代,4组的父本体重无显著差异,每个组4个平行,每个平行雄蟹10只、雌蟹20只。每个网箱放养中华绒螯蟹大眼幼体500只,以水花生(Altemanthena philoxeroides)为隐蔽物,保持生长环境尽量相同且适宜生长。经过158 d的养殖,A、B、C和D组个体的体重从(6.0±0.5)mg分别增长到(7 599.8±954.8)mg、(6 232.7±638.7)mg、(6 112.4±854.6)mg、(5 316.0±745.3)mg,分别增长了1 266.6、1 038.8、1 018.7和886.0倍,且A组特定生长率显著高于D组(P0.05)。蜕壳11次成长为1龄蟹种后综合指标(体重、壳长、壳宽、体高)最好的是A组,A组显著好于B、C、D组(P0.05);次之为B、C组,再者是D组,B与C组差异不显著(P0.05),但均显著好于D组(P0.05)。B组成活率最高,分别比A、D、C组高1.4%、3.6%、4.6%;次之为A组,分别比D、C组高2.2%、3.2%;再者为D组,比C组高1.4%。综合研究表明,在1龄蟹种阶段,大规格母本后代生长性状表现出优于小规格母本后代的趋势。     

Adhesive organs of the gastrotricha

Summary Adhesive organs of 17 gastrotrich species of the order Macrodasyida and 2 species of the order Chaetonotida (Chaetonotida-Paucitubulatina) can be seen by transmission electron microscopy to comprise two gland cell types. These cells are morphologically similar to viscid and releasing glands of the Turbellaria and so are identified by these same names; the adhesive system in these gastrotrichs is therefore called a duo-gland system considered at least functionally comparable to the duo-gland organs of turbellarians. The two gland cell types project their necks through tubiform extensions of the animal's cuticle. Some adhesive tubules have only one of each gland type; others, even in the same species, may have two viscid and one releasing glands; and compound organs such as posterior footlike appendages may have three and four viscid glands and one releasing gland per tubule. Gland cells in some species have fibers, evidently cytoskeletal in function. The adhesive tubules are quite similar in all of these species and provide few characters for determining within-group relationships of the gastrotrichs. The duo-gland system of the Gastrotricha is probably not homologous with that of the Turbellaria.Abbreviations Used in Figures cu cuticle - ep epidermal cell - f fiber - la lateral adhesive organ - m muscle - pa posterior adhesive organ - rg releasing gland - sc sensory cilium - scb sensory cell body - vg viscid gland This research was supported by NSF grants DEB-77-06058 (S. Tyler, P.I.) and GB 42211 (R.M. Rieger, P.I.)     

Adhesive crosstalk in gastrulation

Recent studies show that signaling through integrin receptors is required for normal cell movements during Xenopus gastrulation. Integrins function in this process by modulating the activity of cadherin adhesion molecules within tissues undergoing convergence and extension movements.     

Adhesive substrates for fibronectin

In order to promote cell attachment, fibronectin must first undergo activation by a suitable substrate. In this study, 52 materials have been surveyed for their ability (a) to bind fibronectin, (b) to activate the cell-adhesive property of fibronectin, and (c) to support the growth of cells. Many plastics, polysaccharides, metals, and ceramics were found to support cell growth as well as the fibronectin-dependent attachment of cells. Several other substrates have been identified that were inactive in promoting either cell attachment or growth. Hydrophobic substrates were found to be active in fibronectin activation, whereas hydrophilic substrates were found to be inactive. Since fibronectin binds to substrata of extremely varied chemical composition, it is clear that the binding of fibronectin to such substrata is nonspecific in nature. Since protein pretreatment of all substrata, except collagen and poly(L-lysine), abolished the physical binding of fibronectin, the binding of fibronectin to artificial substrata is probably ascribable to a nonspecific hydrophobic protein-substratum interaction. In contrast, several lines of evidence indicate that the interaction between fibronectin and collagen displays biological specificity. Poly(hydroxyethylmethacrylate)(poly(HEMA)), which has previously been shown to be nonadhesive for cells, is demonstrated here to be unique in its inability to bind fibronectin. Addition of one part per million of an adhesive polymer to poly(HEMA) permits fibronectin binding to occur.     

Adhesive properties of sea cucumber coelomoyctes

Summary— The adhesive properties of the coelomocytes of the sea cucumber, Holothuria polii, have been investigated by studying their ability to attach to glass coverslips in vitro, and their morphology examined by scanning electron microscopy. Both amoeboyctes and spherule cells in cell suspensions attached themselves to glass coverslips, but spreading activity was restricted to an amoebocyte subset which assumed an extremely flattened morphology. Coelomocyte adhesion was a time- and temperature-dependent phenomenon and required cations for attachment to the glass surface. Mg²⁺ ions were more effective than Ca²⁺ in facilitating cell binding. The addition of potassium cyanide or sodium azide to the cell suspension did not inhibit amoebocyte attachment but vinblastine did. Cytochalasin B had no effect. Cell adhesiveness was greatly enhanced with both coelomic fluid and purified 200-kDa coelomocyte-aggregating factor.     

Adhesive proteins of the malaria parasite

Malaria infection of the host cells requires host-parasite recognition events mediated by adhesion and signaling molecules. Recent development of systems for stable transformation and targeted integration of exogenous DNA in malaria parasites provides a powerful tool to study the structure and function of Plasmodium attachment motifs, and their role in infection and disease.