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81.
目的:为了优化风痛灵颗粒的制各工艺。方法:采用正交试验以阿魏酸、多糖等为指标。结果:得出最佳的浸提工艺参数,同时考察了最佳的喷雾干燥及制粒条件。结论:本方法是风痛灵颗粒的最佳的制备方法。 相似文献
82.
83.
人体下颌牙槽骨皮质骨是各向异性复合生物材料,组织结构上类似于胶原羟磷灰石纤维增强的单向纤维增强复合材料。本文应用电测法测试了不同状态人体下颌牙槽骨皮质骨在平面应力状态下的各向异性弹性常数。 相似文献
84.
85.
三袖套管法大鼠肺移植 总被引:12,自引:2,他引:10
我们将血管套接技术用于大鼠肺移植中。在肉眼下,完成肺动静脉及支气管的吻合。在连续6例手术中,手术平均时间61±4分钟,移植物总缺血时间17±3分钟,手术时间缩短至国外同类手术的1/4,缺血时间缩短至同类手术的1/3。同时手术成功率达到75%(6/8),手术后生存率100%。行对侧肺切除术后,血气分析正常,显示了移植肺良好的气体交换功能 相似文献
86.
Oblique transcorporeal approach to anteriorly located lesions in the cervical spinal canal 总被引:2,自引:0,他引:2
Summary The technique of obliquely drilling out the postero-lateral part of the cervical vertebral bodies is described. It uses the antero-lateral (retro carotico-jugular) approach to control and displace the vertebral artery postero-laterally and to expose the lateral aspect of the vertebral bodies. It provides, through a wide field and with minimal retraction of the carotid artery and the internal jugular vein, an extensive view of the anterior aspect of the spinal cord. It has already been used to treat 15 anterior lesions compressing the spinal cord including neurinomas and osteophytes. 相似文献
87.
向42只黄雀的延髓展状核加压注入或微电泳泳入HRP后,在同侧的脑桥上橄榄核、对侧的脑桥外侧丘系腹核及中脑外侧核背侧部内见到密集的顺行标记终末或纤维;在双侧的延髓巨细胞核出现了大量的逆行标记细胞;在对侧的层状核内既有密集的标记终末又有一些标记细胞.结果表明:层状核的传出纤维投射到同侧上橄榄核,经外侧丘系走行至对侧的外侧丘系腹核和中脑外侧核背侧部,双侧的层状核之间也有交互投射。此外,层状核接受耳蜗亚核──双侧巨细胞核的传入投射.因此,层状核是听觉上行通路中的第二级中继站. 相似文献
88.
Human ocular counterroll: assessment of static and dynamic properties from electromagnetic scleral coil recordings 总被引:1,自引:0,他引:1
H. Collewijn J. Van der Steen L. Ferman T. C. Jansen 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1985,59(1):185-196
Summary Static and dynamic components of ocular counterroll as well as cyclorotatory optokinetic nystagmus were measured with a scleral search coil technique. Static counterroll compensated for about 10% of head roll when the head was tilted to steady positions up to 20 deg from the upright position. The dynamic component of counterroll, which occurs only while the head is moving, is much larger. It consists of smooth compensatory cyclorotation opposite to the head rotation, interrupted frequently by saccades moving in the same direction as the head. During voluntary sinusoidal head roll, cyclorotation compensated from 40% to more than 70% of the head motion. In the range 0.16 to 1.33 Hz, gain increased with frequency and with the amount of visual information. The lowest values were found in darkness. The gain increased in the presence of a visual fixation point and a further rise was induced by a structured visual pattern. Resetting saccades were made more frequently in the dark than in the light. These saccades were somewhat slower than typical horizontal saccades. Cyclorotatory optokinetic nystagmus could be induced by a patterned disk rotating around the visual axis. It was highly variable even within a same subject and had in general a very low gain (mean value about 0.03 for stimulus velocities up to 30 deg/s). It is concluded that cyclorotational slip velocity on the retina is considerably reduced by counterroll during roll of the head, although the residual cyclorotation after the head has reached a steady position is very small. 相似文献
89.
The time of appearance of the truncus arteriosus was studied in the chick embryo using an in ovo labeling technique. Three hundred embryos at stages 13–18 of Hamburger and Hamilton were selectively labeled at the distal end of the heart tube, using gelatine-india ink label; 122 of these embryos were reincubated and 111 of them reached stages 25–28. In these stages the final location of the label was determined. Only 95 of these embryos showed both a normal heart and a label located in it. The remaining embryos were discarded due to abnormal cardiac morphology or because the label was not found. Embryos labeled at stages 13–14 had label in the conus in 42.8% of the cases and in the boundary between the conus and the truncus arteriosus in 57.1% of the cases. Label placed at stages 15–16 was located in the conus in 6.1% of the cases, in the boundary between the conus and the truncus arteriosus in 44.8% of the cases, and in the truncus arteriosus in 48.9% of the cases. Finally, label placed at stages 17–18 was located in the boundary between the conus and the truncus arteriosus in 18.7% of the cases and in the truncus arteriosus in 81.2% of the cases. Our results permit us to conclude that the truncus arteriosus appears in the chick embryo as early as stages 15–16 of Hamburger and Hamilton (50–56 hours of incubation). © 1993 Wiley-Liss, Inc. 相似文献
90.
S. Hering D. J. Beech T. B. Bolton S. P. Lim 《Pflügers Archiv : European journal of physiology》1988,411(5):590-592
The actions of nifedipine or BAY K 8644 were studied on barium currents recorded from single, collagenase- and elastase-dispersed, smooth muscle cells from the rabbit ear artery using the whole-cell configuration of the patch-clamp technique. Nifedipine (3M) caused a reduction in the barium current (IBa) evoked by steps to potentials positive of-10mV. This was characterized by a pronounced initial block, an increase in the rate of current decay during the voltage-clamp step, but by no increase in block if pulses were repeated every 600ms. Rapid extracellular application of nifedipine (1M) during the sustained current component (using a new concentration-jump technique) was found to have no effect on IBa over 4s at +20mV, but after returning to the holding potential (-60mV) for 10s, sustained IBa was subsequently abolished. BAY K 8644 (1M) increased IBa at all potentials, and on rapid application during the sustained current component markedly potentiated IBa. The results suggest that nifedipine binds with high affinity to the closed, available state of the Ca++ channels but they do not suggest binding to the open or inactivated states. The effect of BAY K 8644 is consistent with high affinity binding to the open or inactivated and to the closed, available states. 相似文献