良性小脑出血13例分析

笔者对13例良性小脑出血的患者,从起病、临床表现进行了具体分析.总结出中老年良性小脑出血的6个特点,供临床工作者参考.     

Transneuronal degeneration of thalamic neurons following deafferentation: quantitative studies using [3H]thymidine autoradiography.

Transneuronal degeneration of thalamic neurons following partial deafferentation was studied using [3H]thymidine autoradiography. Timed-pregnant female Sprague-Dawley rats received systemic injections of [3H]thymidine on embryonic day (E) 13, 14 and/or 15. On the day of birth, pups were anesthetized by hypothermia and subjected to unilateral enucleation, unilateral removal of the inferior colliculus or sham lesion. Animals were sacrificed on postnatal day 10 or 30 and the brains processed for autoradiography. Material from sham-lesioned animals demonstrates that neurons destined for the dorsal lateral geniculate nucleus (LGd) undergo final mitoses on E13, 14 and 15. Neurons in the ventral medial geniculate nucleus (MGv) undergo final mitoses on E13 and 14. Thirty days following neonatal unilateral eye removal, the contralateral LGd displays a loss of approximately 30-35% of [3H]thymidine labeled neurons. Neonatal unilateral removal of the inferior colliculus results in a loss of approximately 30-40% of labeled neurons in MGv. For both LGd and MGv, shorter survival times reveal less severe cell loss. Late generated (E15) LGd neurons show less severe loss following enucleation than do earlier generated neurons. These results document the degree of cell loss in sensory thalamic nuclei following deafferentation and demonstrate that [3H]thymidine autoradiography provides a useful quantitative method for assessing anterograde transneuronal cell loss in targeted populations of neurons in the developing central nervous system.     

Calcium, network activity, and the role of NMDA channels in synaptic plasticity in vitro.

Functionally effective neuronal circuits are constructed through a competitive process that requires patterned neuronal activity elicited by structured input from the environment. To explore the mechanisms of this activity-dependent synaptic restructuring, we have developed an in vitro preparation of mouse spinal cord neurons maintained in a 3-chambered cell-culture system. Sensory afferents that received chronic electrical stimulation for 3-5 d developed stronger synaptic connections than unstimulated afferents converging onto the same postsynaptic spinal cord neuron. Exposure to 100 microM DL-2-amino-5-phosphonovaleric acid (APV), an antagonist of the NMDA channel, during the stimulation period prevented the competitive advantage associated with electric stimulation. However, when APV was applied with a higher concentration of calcium (3 mM), activity-dependent synaptic plasticity was no longer inhibited by the NMDA receptor antagonist. This reversal of APV block of the plasticity was not impaired by reducing transmitter release with 3 mM magnesium (in addition to 3 mM calcium and APV). A suppressant effect of APV on spontaneous activity was observed, which was attributed to loss of the NMDA component of the EPSP. Activity-dependent plasticity was also blocked if spontaneous activity was suppressed with dilute tetrodotoxin (TTX; 5-10 nM), a dosage that reduces excitability of neurons but is insufficient to block sodium-dependent action potentials. These experiments bring into question how NMDA channel activation is involved in the processes of synaptic remodeling during development. The data suggest that postsynaptic activity is required for synaptic remodeling, but this activity need not involve NMDA receptor activation specifically for activity-evoked synaptic plasticity. Instead, the mechanism for plasticity appears to operate through calcium-dependent processes in general.     

膨润土对药用混悬液助悬性能的考察

本文报道了无机胶体膨润土(Bentonite)作为助悬剂在炉甘石洗剂中的应用,并与有机助悬剂及另一种无机胶体XVT—M进行比较,显示了其优异的助悬性能。     

来源于骨髓和脐带血的基质细胞基本特性的比较

目的比较骨髓与脐带血细胞体外培养基质细胞的基本特性,为基质细胞的选择应用提供依据.方法用Dexter长期培养体系培养骨髓和脐带血基质细胞,以细胞增殖、细胞形态、细胞化学染色、细胞表面及基质细胞支持另一骨髓细胞形成的鹅卵石造血区(CAFC),长期培养起始细胞(LTC-IC)为指标,比较两者的生长特性、成分及功能.结果①细胞生长特性:出现贴壁细胞时间,骨髓细胞为培养3d,脐带血细胞为培养5～6d;细胞融合成片时间,骨髓细胞为培养10～14d,脐带血细胞为培养12～18d;第21天细胞增殖数,骨髓比脐带血细胞增殖少;②细胞成分:21d培养后细胞成分,骨髓来源者以成纤维细胞为主,其次是巨噬细胞与内皮细胞,脂肪细胞最少;脐带血细胞来源者,以巨噬细胞为主,其次是内皮细胞、成纤维细胞,偶见脂肪细胞;细胞化学与上述结果基本一致;细胞表面抗原检测,CD14、CD45的表达骨髓细胞明显低于脐带血细胞;③细胞功能:骨髓来源的基质细胞较脐带血细胞的基质细胞支持另一骨髓细胞形成的CAFC和LTC-IC明显多.结论①生长特征:形成贴壁细胞时间骨髓较脐带血短,骨髓细胞比脐带血细胞有核细胞数增殖快、持续时间相对短;②细胞成分特性:骨髓来源形成的基质细胞以成纤维细胞为主,脐带血来源者以巨噬细胞为主;③细胞功能特性:骨髓细胞形成的贴壁细胞较脐带血细胞形成的贴壁细胞更利于CAFC、LTC-IC生长.     

神经干细胞移植治疗缺氧缺血性脑损伤的实验研究

目的 研究神经干细胞移植治疗缺氧缺血性脑损伤的可行性。方法 取孕龄为12－16天的母鼠，从胎脑中分离神经细胞，进行培养、鉴定。用出生7天的SD大鼠的新生鼠制作缺氧缺血性脑损伤的动物模型，7天后接受神经干细胞移植（移植组，n＝16只），同时设置对照组，只注射磷酸缓冲液（对照组，n=8只），8－10周后，作Y迷宫实验检测大鼠的学习能力和记忆能力。取脑组织作免疫组织化学检查。结果 从大鼠胎脑中成功培养出神经干细胞，培养条件下呈悬浮状态生长，形成神经球，绝大多数的细胞表达神经干细胞的标志物神经巢蛋白（nestin）。接爱神经干细胞移植组大鼠的学习能力、记忆能力和对照组相比，有明显提高，差异具有显著性（P＜0.05）。接受神经干细胞移植大鼠组织中可见存活的移植细胞，并和宿主脑组织融合在一起。结论 在体外培养条件下，可从胎脑组织中培养出神经干细胞，移植到缺氧缺血性脑损伤大鼠脑内后，细胞与宿主的脑组织融合在一起，动物的学习、记忆能力有改善。移植神经干细胞是治疗缺氧缺知性脑损伤的有效方法之一。     

胞嘧啶脱氨酶的原核表达和多克隆抗体的制备

目的：在原核系统中表达并纯化大肠杆菌胞嘧啶脱氨酶（cytosine deaminase,CD)，制备鼠抗大肠杆菌CD多克隆抗体，方法：亚克隆CD基因到原核表达载体pMAL-c2和pBV222中，并转化入大肠杆菌DH5α内，诱导表达并纯化MBP-CD和6his-CD融合蛋白，用纯化的MBP-CD融合蛋白免疫小鼠制备多克隆抗体。结果：通过重组质粒的酶切筛选出重组阳性克隆，成功地表达和纯化出MBP-CD和6his-CD融合蛋白，用纯化的MBP-CD成功制备了鼠抗CD多克隆抗体，并用6his-CD和GST-CD重组蛋白进行Western印迹分析，证实了抗体的正确性，结论：应用多克隆抗体可以检测体内外CD基因的表达，为临床前和临床上深入开展CD基因的生物治疗研究提供重要的实验材料。     

影像学检查在儿童过敏性紫癜的临床价值

目的探讨儿童过敏性紫癜的影像学特点及其临床价值。方法回顾性分析32例过敏性紫癜并发肠套叠患儿的临床及影像学资料。结果出现并发症之前过敏性紫癜的腹部X线主要表现为局限性小肠充气扩张，粘膜增粗，肠间隙增宽，可伴有液平；B超显示为不同程度的多发节段性肠壁水肿增厚，肠管狭窄等表现；出现并发症后，其X线表现加重，部分病例伴有肠穿孔；B超及X线监视下空气灌肠可以明确是否并发肠套叠，部分病例可通过空气灌肠达到复位治疗的目的。结论影像学检查的重要临床价值在于能与需要手术治疗的其他急腹症相鉴别，同时可以了解其是否并发常见的并发症，为临床确定治疗方案提供可靠的信息。     

Plasma proteins in a standardised skin mini-erosion (II): effects of extraction pressure

Background  

A standardised suction technique has been used to sample plasma proteins in dermal interstitial fluid (IF) serially for 5 to 6 days from a suction-induced skin mini-erosion. Increased protein concentrations ascribed to inflammation have been shown from day 1 onward. In this study, we assessed the effect of two different extraction pressures on IF sample composition.