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11.
制作备用根大鼠脊髓后角提取液,取其分子量大于10kD的组分进行SDS-聚丙烯酰胺凝胶电泳分析,发现手术侧和非手术侧的电泳区带数目大致相同,但手术侧样品的第四条蛋白质区带扫描的吸收峰面积百分比大于非手术侧样品的第四条区带,两者在量上可能有差别。将手术侧样品经交联葡聚精G-75凝胶层析,得到两个洗脱峰.第一峰洗脱液有促进体外培养的背根节神经元存活及其突起生长的作用,其电泳分析显示4条主带,分子量在40~80kD之间.实验结果提示部分去传入纤维支配的脊髓后角组织含有神经营养活性物质,该物质的分子量约在40~78kD之间.  相似文献   
12.
We have developed an isolated spinal cord-skin preparation of the newborn rat. The spinal cord together with a piece of skin connected to the cord by the saphenous nerve was isolated from 1- to 4-day-old rats and separately superfused with artificial cerebrospinal fluid in two neighbouring chambers. Potentials were recorded extracellularly from the third lumbar ventral root. Application of capsaicin (0.5-2 μM) or KCl (60–350 mM) with brief pressure pulses to the perfusion bath of the skin evoked a depolarizing response of 20- to 40-s duration in the ventral root. The response was depressed by [Met5]enkcphalin (0.03–3 μM). morphine (0.1–2 μM) and a tachykinin antagonist, [D-Arg1,D-Trp7,9,Leu11] substance P (spantide), 1–10 μM), applied to the spinal cord by superfusion, whereas the response was augmented by centrally administered calcitonin gene-related peptide (0.1–0.2 μM) or bicuculline (0.5–1 μM).  相似文献   
13.
Development and evaluation of a presurgical preparation program   总被引:2,自引:1,他引:1  
Three presurgical preparation programs were developed and evaluated in an Australian hospital utilizing an additive component design. The component basic to all three preparation programs was modeling. This technique was compared with the additional components of teaching child coping skills and parent coping skills via videotape. Subjects were 28 children between the ages of 4 and 13 years who were scheduled for elective surgery. Anxiety of both the children and parents was assessed by self-report and behavior observation. Results indicated that there was no further anxiety reduction by the addition of child and parent coping skills. Results are discussed in terms of the viability of teaching coping skills via videotape particularly to parents. Methodological difficulties associated with research in this area are examined.  相似文献   
14.
The issue of the preparation of effective teachers becomes more critical for teachers of early childhood programs. It has been hypothesized that better program quality depends on better-educated teachers. The purpose of this investigation was to explore the importance of a high level of education for all early childhood education teachers. This issue has intrigued early childhood researchers and has prompted a large amount of research studies over the past decades. In order to assess the status of this line of inquiry and to provide guidance for future research, a critical analysis of 40 studies on the preparation of early childhood education teachers and the quality of their educational programs that were published within a 15-year (1989-2004) period is presented here. The analysis consisted of literal and allegorical critical analysis and interpretative critical analyses, which generated results in three main areas that focused on the professional development of the teachers, including teachers' professional development, the importance of a Bachelor's Degree and educational standards for early childhood education teachers.  相似文献   
15.
用乙二醇法诱导大鼠产生草酸钙结石,用45~Ca示踪测定法了解中草药复方制剂(PESM)对草酸钙结石形成的抑制作用。结果显示,实验组肾脏放射性强度明显减少(实验组3.47±3.52cpm/mg,对照组10.89±14.24cpm/mg)。干肾重量明显下降(实验组306.0±47.0mg,对照组343.1±59.4mg),说明PESM能明显抑制肾脏草酸钙结石的形成。  相似文献   
16.
中药白芷硫熏前后香豆素成分含量比较   总被引:16,自引:6,他引:10  
用薄层扫描法对川白芷和杭白芷药材加工(硫熏)前后的香豆素类成分进行了含量测定。香豆素含量分别为0.190%、0.571%、0.178%、0.421%。  相似文献   
17.
以头孢呋辛钠为原料,从制备(R,S)-乙酸1-溴乙酯开始。经酯化反应的溶剂沉淀过程无须分离直接制得高纯度非晶型的头孢呋辛酯。本制备方法简便,适于工为化生产。  相似文献   
18.
Magnetization prepared segmented acquisition requires a view order that maximizes signal contrast during the acquisition of the central portion of k-space. Steady state free precession (SSFP) acquisition further requires a view order that minimizes changes in phase-encoding gradients from one repetition to the next in order to minimize eddy current artifacts. In this article, optimal view ordering schemes satisfying these two requirements are formulated and applied to inversion prepared 3D SSFP contrast-enhanced MR angiography (MRA). Experiments on phantoms and pigs demonstrated improved background suppression and reduced image artifacts.  相似文献   
19.
3—氯—4—氟苯胺的生产与研究概况   总被引:1,自引:0,他引:1  
评述了3-氯-4-氟苯胺的实验室研究和工业生产现状,特别对氯化、硝化、氟化和还原等反应中间体的制备及其质量作了分析。  相似文献   
20.
愈银汤3号存临床银屑病的治疗中作用确定,银屑病在临床中可分为寻常型、脓疱型、关节病型、红皮病型银屑病,其发病原因有很大的不同.在治疗中应辩证治疗。  相似文献   
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