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1.
The melt agglomeration process of lactose powder with hydrogenated cottonseed oil (HCO) as the hydrophobic meltable binder was investigated by studying the physicochemical properties of molten HCO modified by sucrose stearates S170, S770 and S1570. The size, size distribution, micromeritic and adhesion properties of agglomerates as well as surface tension, contact angle, viscosity and specific volume of molten HCO, with and without sucrose stearates, were examined. The viscosity, specific volume and surface tension of molten HCO were found to be modified to varying extents by sucrose stearates which are available in different HLB values and melt properties. The growth of melt agglomerates was promoted predominantly by an increase in viscosity, an increase in specific volume or a decrease in surface tension of the molten binding liquid. The agglomerate growth propensity was higher with an increase in inter-particulate binding strength, agglomerate surface wetness and extent of agglomerate consolidation which enhanced the liquid migration from agglomerate core to periphery leading to an increased surface plasticity for coalescence. The inclusion of high concentrations of completely meltable sucrose stearate S170 greatly induced the growth of agglomerates through increased specific volume and viscosity of the molten binding liquid. On the other hand, the inclusion of incompletely meltable sucrose stearates S770 and S1570 promoted the agglomeration mainly via the reduction in surface tension of the molten binding liquid with declining agglomerate growth propensity at high sucrose stearate concentrations. In addition to being an agglomeration modifier, sucrose stearate demonstrated anti-adherent property in melt agglomeration process. The properties of molten HCO and melt agglomerates were dependent on the type and concentration of sucrose stearate added.  相似文献   
2.
指背腱膜的解剖学研究   总被引:1,自引:1,他引:0  
目的 探讨指背腱膜的构成特点及临床意义。方法 在30只成人尸体手标本上,通过模拟手术,对指背腱膜的构成特点进行了应用解剖学观测。结果 指背腱膜的构成复杂,其中的外侧腱束、外侧束、外侧腱和中央束在手指畸形的发生中有着特殊的临床意义。外侧腱束主要形成伸近节指间关节的功能解剖机制;其与外侧束形成的密切纤维联系而具有协同外侧腱的功能;该腱束与屈肌腱鞘有联系又使其具有平衡屈肌和伸肌肌力的作用。中央束在指背腱膜的整体协调、畸形的发生及矫正过程中起着重要的功能。结论 通过对指背腱膜的解剖研究,可以解释因指屈、伸肌腱平衡被破坏后所形成的畸形。  相似文献   
3.
目的:探讨海绵窦上段动眼神经的应用解剖并讨论其临床意义。方法:经血管灌注后观测10例尸颅的海绵窦上段动眼神经及其毗邻与血供。结果:海绵窦上段动眼神经与海绵窦上段背侧紧邻海马钩回,内侧与视交叉、后交通动脉毗邻,外上与脉络膜前动脉相邻,腹侧紧贴鞍背突。海绵窦上段动眼神经80%未见神经外营养血管,可见20%后交通动脉发出1~2根分支进入神经。结论:海绵窦上段动眼神经毗邻结构复杂,滋养血管细小;在海绵窦上缘手术时,应特别注意辨认和保护动眼神经。  相似文献   
4.
5.
The electrodeposition of Ag on Pt(100)-(1 × 1) in perchlorate electrolyte was studied by means of time-resolved in situ scanning tunnelling microscopy (STM) and cyclic voltammetry. One monolayer of Ag is deposited underpotentially (upd) ca. 500 mV positive of the Ag+/Ag equilibrium potential. Several millivolts positive of the equilibrium potential, a second well defined upd layer forms. Its growth was observed to proceed via island formation and coalescence. This process occurs in two separate stages that manifest themselves in voltammetric peaks as well as in the STM images.  相似文献   
6.
The morphological types of ganglion cells in the dog and wolf retina were studied by intracellular staining with Lucifer Yellow. These retinae contain a range of ganglion cell types that closely correspond to those found in cat retina: alpha cells with large somata and large, relatively densely branched dendritic trees; beta cells with medium-sized somata and small, densely branched dendritic trees; and a variety of other types with smaller somata and varying dendritic branching patterns and dendritic field sizes. The correspondence of canine and cat ganglion cell types strengthens the view that there is a common set of ganglion cell types in carnivores. Alpha and beta cell dendritic trees of dog and wolf are monostratified in either the inner or the outer part of the inner plexiform layer, suggesting an on/off dichotomy in the response to light. Dendritic field sizes of dog alpha and beta cells increase from the central area to peripheral retina: alpha cell fields from 160-200 microns to about 1,100 microns diameter, and beta cell fields from 25 microns to about 360 microns diameter. These sizes are quantitatively very similar to those found in cat retina. The close qualitative and quantitative morphological correspondence of cat and dog ganglion cells suggests that they are also functionally very similar. It is likely that dog alpha cells have brisk-transient (Y), and dog beta cells brisk-sustained (X) concentric receptive fields. From the smallest beta cell sizes it is concluded that the visual acuity of the dog may be as good as that of the cat.  相似文献   
7.
小脑延髓池的显微外科解剖研究   总被引:1,自引:1,他引:0  
目的研究小脑延髓池的显微外科解剖特征,探讨其临床意义.方法选择经10%福尔马林固定成人头颈标本15例,显微镜下(5~25倍)模拟枕下极外侧入路、颈-乳突入路和耳前颞下窝入路的手术操作,分别自后、侧和前方显露小脑延髓池内结构,详细观测其神经血管结构的形态特征.结果小脑延髓池位于延髓外侧,上至桥延沟,下达枕骨大孔,侧方沿枕骨形成蛛网膜袖套进入颈静脉孔和舌下神经管.舌咽神经、迷走神经和副神经的根丝自上而下起自橄榄体背侧、延髓和脊髓的后外侧沟,根丝逐级汇合后分别进入舌咽神经道和迷走神经道.椎动脉于小脑延髓池的下端入颅后经该池行向前上内进入延髓前池.小脑下后动脉(PICA)可分为延髓前段、延髓侧段、扁桃体延髓段、脉络膜扁桃体段和皮质段.主要的静脉有小脑延髓裂内静脉、延髓静脉、小脑岩面下组静脉和岩下桥静脉.结论小脑绒球和Luschka孔脉络丛复合体及颈静脉孔硬膜返折可作为辨认舌咽神经脑池段的解剖标志,深刻认识小脑延髓池的蛛网膜界限对手术处理累及小脑延髓池的不同性质病变,保护重要神经功能意义重大.  相似文献   
8.
9.
UB-I粘结剂粘结面的微形态观察   总被引:1,自引:0,他引:1  
目的:研究UB-Ⅰ粘结剂的粘结界面和粘结表面的微形态特点。方法:用扫描电子显微镜观察UB-Ⅰ和牙本质的粘结界面和粘结表面。结果:UB-Ⅰ粘结剂在牙本质小管内可聚合形成树脂突,在牙本质小管内的树脂突表面有树脂侧枝呈树枝状横行排列,并且和相邻的树脂突相连接,在牙本质和复合树脂之间有杂合层形成。结论:UB-Ⅰ粘合剂具有良好的渗透性,与牙本质之间可以形成良好的机械嵌合。  相似文献   
10.
This study examined the impact of implementing a rotating dissection schedule on the attitudes and performance of first-year dental students in the gross anatomy laboratory at the University of Kentucky. In 2002-2003, half of the students assigned to each cadaver dissected the assigned objectives during the first 90 min of the laboratory session. During the last 30 min, the non-dissecting group members came into the laboratory and had the day's dissection demonstrated and explained to them via peer instruction. Dissection responsibilities rotated with each laboratory session. Eighty-eight percent of student participants were satisfied with the rotating dissection approach according to a mid-term survey, and this satisfaction level remained unchanged at the end of the semester for most students. Students' perceptions of the quality of peer laboratory presentations varied, with only 44% rating them as good or better. Eighty percent of students perceived that rotating dissection did not impede their performance, and this was confirmed by analysis of grade data. Student satisfaction and the ability to devote additional weekly curriculum time to studying anatomy in a very compressed curriculum were the main student-described benefits.  相似文献   
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