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21.
目的 研究臂丛神经根单发断,2根切断(不同方式联合)及3根切断后对肢体的影响,为治疗臂丛根性撕脱伤寻找更多的潜在移位神经,方法 252只SD大鼠随机分为13组:(1)第1-5组(单根神经根切断组);每组12只大鼠。分别切断C5-8T1各神经根;(2)第6-12组(2根神经根切断组);每组24只大鼠。分别切断相邻及不相邻2根神经根,即C5,6,C6,7,C7,8,C8T1,C5,7,C6,8和C7T  相似文献   
22.
腧穴针感在针刺防治疾病过程中发挥着重要作用。本文从针刺作用的感受器,腧穴针感的外周传入神经,以及针感与中枢神经的关系,诸方面,列举大量实验结果和理论,阐明针感形成的物质基础是神经系统。  相似文献   
23.
Public concern surrounding antibiotic contamination in food and food products has made it imperative to develop analytical methods for their detection. Polyclonal antibodies were used in the development of a surface plasmon resonance (SPR)-based inhibition immunoassay for cephalexin. A conjugate consisting of cephalexin-bovine serum albumin (BSA) was immobilized on the dextran gel surface of the sensor chip. Binding/regeneration studies of antibody to immobilized cephalexin were studied and dissociation of the antibody from the immobilized cephalexin was easily achieved with 10 mmol l-1 NaOH. Forty surface regeneration cycles were carried out and found to be reproducible with only a 7.4% decrease in binding over this number of regenerations. Model inhibition immunoassays for cephalexin were developed in PBS and spiked milk samples with detection ranges of 4.88 to 2,500 ng ml-1 and 244 to 3,906 pg ml-1, respectively.  相似文献   
24.
Summary The long term results of 21 cases of cross-face nerve grafting are presented and analyzed to evaluate the value of the procedure. The follow-up period extended beyond 3 years in all cases as the final assessment of the facial reanimation is only possible after a very long time interval. A satisfactory or good reanimation of the face occurred in 80% of the patients. In well defined cases the procedure may be considered a valuable tool in the rehabilitation of the paralyzed face.  相似文献   
25.
神经电生理检测对多灶性运动神经病诊断价值的初步研究   总被引:5,自引:0,他引:5  
目的 探讨神经电生理检查在多灶性运动神经病(MMN)中的诊断价值。方法对16例MMN患者及16名健康对照进行运动神经传导速度和感觉神经传导速度检查,记录刺激引出的复合肌肉动作电位的波幅、波宽、面积、位相和时限,进行对比分析,判定是否有运动神经传导阻滞(CB)或暂时性离散(TD),并有选择性地进行常规肌电图检查。结果16例患者均可见有一根以上运动神经或至少一根运动神经的一个以上部位出现CB或CD。其中13例双上肢正中神经,尺神经出现CB,3例以正中神经、尺神经的远端出现CB首发,随病情进展出现下肢腓深神经CB。仅有2例感觉神经传导速度稍有减慢,波幅略有降低。16例患者神经受累区域以下所支配肌肉肌电图检查见有神经源性损害。结论MMN是一种以远端神经受累为主的不对称性周围神经病,神经电生理检查对诊断和鉴别诊断.MMN起重要作用,CB是MMN的主要神经电生理表现。  相似文献   
26.
Axotomy of the rat facial nerve leads to mitotic divisions of microglial cells without developing into phagocytes. In order to study the functional characteristics of those activated, i.e., proliferating but nonphagocytic, microglia we investigated the expression of monocyte/macrophage antigens by these cells. Our results show that activated microglia lack monocyte/macrophage antigens recognized by the monoclonal antibodies Ox-41, ED1, ED2, and Ki-M2R but express high levels of CR3 complement receptors in situ.  相似文献   
27.
In order to determine whether the lateral ganglionic eminence (LGE) of the fetal telencephalon is the primary source of striatal precursors in striatal transplants and tissue cultures, cells derived exclusively from the LGE of fetal rat brains were transplanted into the quinolinic-acid-lesioned striatum of adult rats. After 2–3 months they produced grafts that were almost entirely AChE-positive as well as DARPP-32-, TH-, and calbindin-immunoreactive. The grafts were integrated into the host striatum so that host corticofugal fiber tracts interdigitated with graft tissues similar to the way they penetrate the gray matter of the normal striatum. Fast Blue dye injected into the ipsilateral globus pallidus of LGE grafted produced retrogradely labeled neurons within the grafts, but Fluorogold dye injected into the ipsilateral substantia nigra did not. In a separate experiment using DARPP-32-immunohistochemistry as a striatal marker, fetal (E16) and neonatal (P2) rat brains showed DARPP-32 immunoreactivity in the LGE but not in the adjacent medial ganglionic eminence (MGE). In summary, both fetal LGE cells and LGE grafts express specific striatal markers, and LGE grafts integrate into the host striatum and innervate the major striatal efferent target within the host brain. These data suggest that the LGE is the origin of cells committed to striatal phenotypes in the developing brain.  相似文献   
28.
L Gao  J M Kennedy 《Muscle & nerve》1992,15(3):419-429
Ventricular-like and fast myosin heavy chains (VL-MHC and FMHC) are transiently expressed during slow skeletal muscle development. The influence of innervation on repression of these MHC isoforms is investigated over an 84-day time course in: (1) normal anterior latissimus dorsi (N-ALD) muscles, (2) regenerating ALD (R-ALD) muscles, (3) denervated ALD (D-ALD) muscles, and (4) regenerating and denervated ALD (RD-ALD) muscles. Western blotting demonstrates that the VL-MHC is expressed in R-, D-, and RD-ALD muscles, but not in N-ALD muscles. Expression of the VL-MHC is transient in R-ALD muscles. In contrast, VL-MHC expression persists in RD-ALD muscles, and appears with time in D-ALD muscles. FMHC was not detected in N-ALD muscles by Western blotting. Two FMHCs are seen in R-ALD and RD-ALD muscles, and in 13-day embryonic ALD muscles. The slower migrating FMHC (FMHCA) comigrates with developmentally regulated FMHCs in fast pectoralis muscle, while the faster migrating FMHC (FMHCB) comigrates with the faster migrating FMHC in embryonic ALD muscle (13 days in ovo). FMHCB decreases in amount over the time course in R-ALD muscles, while FMHCA persists. In contrast, substantial levels of both FMHCs persist in RD-ALD muscles, and appear with time in D-ALD muscles. The cellular distribution of MHCs is followed by immunocytochemistry. Regenerating cells expressing VL-MHC and FMHC are replaced by a mature population in R-ALD muscles. Some of the mature myofibers in R-ALD muscles express FMHC, but not VL-MHC. In RD-ALD and D-ALD muscles, both regenerating and mature muscle cells are seen which express VL-MHC and FMHC. Our results indicate that innervation is required for the repression of VL-MHC and FMHCB during regeneration of slow muscle.  相似文献   
29.
1. Repair and recovery following spinal cord injury (complete spinal cord crush) has been studied in vitro in neonatal opossum (Monodelphis domestica), fetal rat and in vivo in neonatal opossum. 2. Crush injury of the cultured spinal cord of isolated entire central nervous system (CNS) of neonatal opossum (P4–10) or fetal rats (E15–E16) was followed by profuse growth of fibres and recovery of conduction of impulses through the crush. Previous studies of injured immature mammalian spinal cord have described fibre growth occurring only around the lesion, unless implanted with fetal CNS. 3. The period during which successful growth occurred in response to a crush is developmentally regulated. No such growth was obtained after P12 in spinal cords crushed in vitro at the level of C7–8. 4. In vivo, in the neonatal (P4–8) marsupial opossum, growth of fibres through, and restoration of, impulse conduction across the crush was apparent 1–2 weeks after injury. With longer periods of time after crushing a considerable degree of normal locomotor function developed. 5. By the time the operated animals reached adulthood, the morphological structure of the spinal cord, both in the region of the crush and on either side of the site of the lesion, appeared grossly normal. 6. The results are discussed in relation to the eventual longterm possibility of devising effective treatments for patients with spinal cord injuries.  相似文献   
30.
Introduction - Axon growth and axon regeneration are complex processes requiring an adequate supply of certain metabolic precursors and nutrients. Material and methods - This article reviews the studies examining some of the processes of protein modification fundamental to both nerve regeneration and to the continuous and adequate supply of specific factors such as arginine, S-adenosylmethionine and polyamines. Results - The process of arginylation notably increases following nerve injury and during subsequent regeneration of the nerve, with the most likelyfunction of arginine-modification of nerve proteins being the degradation of proteins damaged through injury. It appears that defective methyl group metabolism may be one of the leading causes of demyelination, as suggested by the observation of reduced cerebrospinal fluid concentrations of s-adenosylmethionine (SAMe) and 5-methyltetrahydrofolate, the key metabolites in methylation processes, in patients with a reduction in myelination of corticospinal tracts. Polyamine synthesis, which depends strongly on the availability of both SAMe and arginine, markedly increases in neurons soon after an injury. This "polyamine-response" has been found to be essential for the survival ofthe parent neurons after injury to their axons. Polyamines probably exert their effects through involvement in DNA, RNA and protein synthesis, or through post-translational modifications that areindicated as the most relevant events of the "axon reaction." Conclusions - Nerve regeneration requires the presence of arginine, s-adenosylmethionine, and polyamines. Further studies are needed to explore the mechanisms involved in these processes.  相似文献   
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