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1.
目的探讨白芷酒炖前后对挥发性成分的影响。方法采用顶空固相微萃取技术(HS-SPME)结合气相色谱-质谱法(GC-MS)对白芷酒炖前后挥发性成分及其相对百分含量进行对比分析。结果从白芷生品中初步检测出53个峰,鉴定出36个成分;从白芷酒炖中检测出32个峰,鉴定出26个成分;与生品成分比较,酒炖白芷中有22种成分未测到,但新增了12种成分,表明酒炖白芷中的挥发性成分的组成和含量均发生了变化。结论白芷酒炖后由于受热及辅料黄酒的作用使挥发性成分的种类及含量发生了明显变化,并存在成分转化,本研究为白芷酒炖的炮制机理及其在都梁丸中应用的物质基础研究提供了科学依据。  相似文献   
2.
以制备晶形、粒度、轴比等满足高性能磁粉要求的铁黄为目标,研究了碱法超细α-FeOOH合成的工艺配方和工艺条件对粒子性能的影响,包括碱比、气量、转速、Fe(OH)_2结晶条件、熟化时间等工艺参数的影响规律。重复稳定地制备出三类超微粒α-FeOOH粒子,其粒度分别为0.18、0.28、0.39μm,分布均匀,无枝叉。  相似文献   
3.
Stephen Girard trader, banker, millionaire, and patriot lived 81 full and exciting years. Apparently born with a blind or amblyopic right eye, he emigrated from Bordeaux. France, via Santa Domingo to the United States, and finally settled in Philadelphia, where he developed a successful maritime trade. Ultimately, Girard became the first multimillionaire in the United States. Extremely generous, he often walked from his home in the center of Philadelphia to his farm in what is now South Philadelphia distributing shoes to needy children. Probably Girard’s most heroic gestures were his gallant fight against the yellow fever epidemic in 1793 and his loan to the U.S. government during the War of 1812, which allowed the bankrupt country to continue the conflict and ultimately to win the war. Presented, in part, at the tenth annual meeting of the David G. Cogan Ophthalmic History Society, the College of Physicians of Philadelphia, March 8 and 9, 1997.  相似文献   
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Previous studies have shown that the amygdala projects to both the mediodorsal thalamic nucleus (MD) and its cortical projection area, the prefrontal cortex (PFC). In this investigation rats received injections of different fluorescent retrograde tracers (true blue and diamidino yellow) into MD and either the lateral, polar, or medial PFC in order to examine the relationship of amygdaloid neurons with cortical and/or thalamic projections. PFC injections labeled neurons in the basolateral (BL), basomedial (BM), ventral endopiriform (EnV), and rostral lateral nuclei as well as the periamygdaloid cortex (PAC) and the medial part of the amygdalohippocampal area (AHA). In BL, which contained the great majority of neurons projecting to PFC, most labeled cells were concentrated in particular parts of the nucleus and were topographically organized. The overwhelming majority of labeled neurons in BL were large pyramidal or piriform cells that correspond to class I neurons described in Golgi studies. Occasional small neurons with thin dendrites were also observed; these cells may be class II neurons. MD injections labeled numerous cells in the anterior division of the cortical nucleus, medial nucleus, and caudomedial part of the central nucleus. Moderate numbers of labeled cells were found in caudal portions of BM and PAC, whereas scattered cells were observed throughout the rest of the amygdala with the exception of the lateral nucleus. In BL and AHA many MD-projecting neurons were observed along nuclear boundaries and in the adjacent white matter. Neurons in BL, BM, and AHA usually had large elongated or irregular somata and two to four primary dendrites that branched sparingly. Other cells had smaller ovoid somata. The morphology and distribution of MD-projection cells in the basolateral amygdala indicate that they are primarily large class II neurons. Double-labeled amygdaloid neurons, labeled by both cortical and thalamic injections, were observed only in a small number of animals. Control experiments suggest that most of the double-labeled cells in these cases were artifacts caused by spread of the thalamic injectate into the third ventricle with subsequent uptake by fibers in the anterior commissure. Thus the findings of this study suggest that different neuronal populations in the amygdala project to the two poles of the MD-PFC system. In the basolateral amygdala class I neurons are the predominant cell type involved in PFC projections, whereas a subpopulation of class II neurons, hitherto thought to be primarily local-circuit neurons, project to MD.  相似文献   
6.
高原牧区犏牛胚胎移植技术的应用研究   总被引:3,自引:0,他引:3  
2000年在海拔3,400m的青海省大同县对当地犏牛、黄牛进行了胚胎移植,移植受胎率44.4%。尤其是犏牛胚胎移植首获成功,是牛胚胎移植技术应用领域的新进展,为不同牛种胚胎移植成功提供了宝贵的科学经验。  相似文献   
7.
本文应用HRP和荧光素标记法对大白鼠外侧隔核的传入性神经纤维联系进行了研究。实验结果表明,外侧隔核的传入神经纤维来源于端脑海马的CA_(1-4)区、杏仁皮质核、内嗅区皮质、斜角带核、视前内侧核、视前外侧核;丘脑的室周核和带旁核;底丘脑的Forel's H_2区和未定带;下丘脑的前核、外侧核、后核以及乳头体上核;中脑的腹侧被盖区。  相似文献   
8.
 Mossy cells in the hilus of the rat dentate gyrus are the main cells of origin of the dentate commissural and associational projections. They project along the septotemporal axis of the dentate gyrus and may thus influence the hippocampal signal flow in a longitudinal direction. To analyze the septal innervation of these hilar neurons, anterograde tracing with Phaseolus vulgaris leucoagglutinin (PHAL) was used in combination with intracellular labeling of mossy cells (Lucifer yellow). Anterogradely labeled septal fibers impinge on proximal and distal dendrites of hilar mossy cells but spare the cell body. In contrast, numerous aspiny hilar neurons, presumably GABAergic interneurons, receive a septal innervation on their somata and proximal primary dendrites. These data demonstrate that septal fibers show a specificity for the dendritic segments of hilar mossy cells. Since mossy cells project predominantly to adjacent hippocampal lamellae, the activity of adjacent portions of the dentate gyrus may be influenced by the septal input onto these neurons. Received: 22 July 1996 / Accepted: 24 October 1996  相似文献   
9.
Summary Efferent neurons in isolated pedal ganglia of the pteropodial mollusc Clione limacina were filled with Lucifer Yellow through the wing nerves. Then the ganglia were illuminated with intense blue light which resulted in the complete inactivation of these neurons. After inactivation of efferent neurons, interneurons of the pedal ganglia continued to generate the locomotor rhythm.  相似文献   
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