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71.
目的 通过使用婴儿运动表现测试(TIMP)对昆明地区168名婴儿进行测试,并与美国常模数据进行比较,分析影响得分的相关因素及临床应用价值,为TIMP的本土化提供一定的参考依据。 方法 对昆明地区168例足月儿及矫正胎龄 34~57+6 周早产儿进行TIMP测试,并记录原始得分及婴儿一般情况。 结果 1)随着婴儿胎龄的增加,TIMP测试得分逐渐升高,且各组测试得分均明显低于同周龄组美国常模标准,差异有统计学意义(t=-3.763、-4.181、-3.554、-3.423、-2.489、-3.463、-4.579、-2.612、-2.359、-3.249、-3.038、-4.248,P<0.05);2)足月儿的TIMP得分高于早产儿(t=2.615,P<0.05);出生体重≥2 500 g婴儿的TIMP得分高于出生体重在1 500~<2 500 g之间的婴儿(t=-2.593,P<0.05);测试时矫正年龄在<40周、40~44周、45~48周、49~52周、≥53周的各组婴儿间TIMP得分比较,差异有统计学意义(F=168.226,P<0.001)。3)出生时胎龄(足月或早产儿),以及进行TIMP测试时的矫正胎龄分组是TIMP得分的影响因素(β=0.164、0.743,P<0.05)。 结论 TIMP评估得分能反映不同矫正胎龄婴儿的运动表现能力,各组测试得分均明显低于同周龄组美国常模标准,因此需要建立中国常模提供本土化数据参考;并对早产儿及低出生体重儿给予早期评估和干预。 相似文献
72.
73.
目的 了解外源性褪黑素对大鼠体温及活动度昼夜节律的影响及其可能的调节机制。方法 正常光照条件下,24h连续记录大鼠的体温及活动度的变化,以不同剂量褪黑素在不同的昼夜时间给药观察体温和活动度节律的变化。结果 大鼠的体温及活动度存在昼夜节律性,给药后昼夜节律性不消失;但体温振幅减小,中值降低。黑暗中期给药后,峰值位相显著延迟;活动度振幅增加,中值显著降低,峰值位相延迟。结论 外源性褪黑素不能使体温或活动度的昼夜节律消失,而只是改变昼夜节律的参数。褪黑素可分别调节体温和活动度的昼夜节律,但对活动度的调节作用更为明显。 相似文献
74.
Casey J. Whife Ann-Maree Vallence Dale W. Edgar Fiona M. Wood 《Burns : journal of the International Society for Burn Injuries》2021,47(2):327-337
ObjectiveNeuroplasticity is the capacity of the brain to change or adapt with experience: brain changes occur with use, disuse, and injury. Repetitive transcranial magnetic stimulation (rTMS) can be used to induce neuroplasticity in the human brain. Here, we examined rTMS-induced neuroplasticity in the primary motor cortex in burns survivors and controls without injury, and whether neuroplasticity is associated with functional recovery in burns survivors.MethodsSixteen burn injury survivors (total body surface area of burn injury <15%) and 13 non-injured control participants were tested. Repetitive TMS (specifically, spaced continuous theta-burst stimulation[cTBS]) was applied to induce neuroplasticity 6 and 12 weeks after injury in burn survivors and in two sessions separated by 6 weeks in controls. Motor evoked potentials (MEPs) elicited by single-pulse TMS were measured before and after rTMS to measure neuroplasticity. Burns survivors completed a functional assessment 12 weeks after injury.ResultsNon-injured controls showed decreased MEP amplitude 15?30 min after spaced cTBS in both experimental sessions. Burn survivors showed a smaller change in MEP amplitude after spaced cTBS compared to controls 6 weeks after burn injury but no difference compared to controls 12 weeks after burn injury. In burn survivors, there was a significant positive association between general health outcome (Short-Form Health Survey) and the change in MEP amplitude after spaced cTBS 12 weeks after injury (r=.73, p = .01).ConclusionsThe current findings suggest that burn survivors have a reduced capacity for neuroplasticity early in the recovery period (6 weeks after injury), which normalizes later in the recovery period (12 weeks after injury). Furthermore, the results provide preliminary evidence to suggest that burn survivors with normalized neuroplasticity 12 weeks after injury recover faster after burn injury. 相似文献
75.
Masaaki UNO Kenji YAGI Hiroyuki TAKAI Naoki OYAMA Yoshiki YAGITA Keita HAZAMA Hideki NAKATSUKA Shunji MATSUBARA 《Neurologia medico-chirurgica》2021,61(2):124
We compared the rate of selective shunt and pattern of monitoring change between single and dual monitoring in patients undergoing carotid endarterectomy (CEA). A total of 121 patients underwent 128 consecutive CEA procedures. Excluding five procedures using internal shunts in a premeditated manner, we classified patients according to the monitoring: Group A (n = 72), patients with single somatosensory evoked potential (SSEP) monitoring; and Group B (n = 51), patients with dual SSEP and motor evoked potential (MEP). Among the 123 CEAs, an internal shunt was inserted in 12 procedures (9.8%) due to significant changes in monitoring (Group A 5.6%, Group B 15.7%, p = 0.07). The rate of shunt use was significantly higher in patients with the absence of contralateral proximal anterior cerebral artery (A1) on magnetic resonance angiography (MRA) than in patients with other types of MRA (p <0.001). Significant monitor changes were seen in 16 (12.5%) in both groups. In four of nine patients in Group B, SSEP and MEP changes were synchronized, and in the remaining five patients, a time lag was evident between SSEP and MEP changes. In conclusion, the rate of internal shunt use tended to be more frequent in patients with dual monitoring than in patients with single SSEP monitoring, but the difference was not significant. Contralateral A1 absence may predict the need for a shunt and care should be taken to monitor changes throughout the entire CEA procedure. Use of dual monitoring can capture ischemic changes due to the complementary relationship, and may reduce the rate of false-negative monitor changes during CEA. 相似文献
76.
77.
78.
M. Takada H. Tokuno A. Nambu M. Inase 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,120(1):114-128
It is an important issue to address the mode of information processing in the somatic motor circuit linking the frontal cortex
and the basal ganglia. In the present study, we investigated the extent to which corticostriatal input zones from the primary
motor cortex (MI), the supplementary motor area (SMA), and the premotor cortex (PM) of the macaque monkey might overlap in
the putamen. Intracortical microstimulation was performed to map the MI, SMA, and dorsal (PMd) and ventral (PMv) divisions
of the PM. Then, two different anterograde tracers were injected separately into somatotopically corresponding regions of
two given areas of the MI, SMA, PMd, and PMv. With respect to the PMd and PMv, tracer injections were centered on their forelimb
representations. Corticostriatal input zones from hindlimb, forelimb, and orofacial representations of the MI and SMA were,
in this order, arranged from dorsal to ventral within the putamen. Dense input zones from the MI were located predominantly
in the lateral aspect of the putamen, whereas those from the SMA were in the medial aspect of the putamen. On the other hand,
corticostriatal inputs from forelimb representations of the PMd and PMv were distributed mainly in the dorsomedial sector
of the putamen. Thus, the corticostriatal input zones from the MI and SMA were considerably segregated though partly overlapped
in the mediolateral central aspect of the putamen, while the corticostriatal input zone from the PM largely overlapped that
from the SMA, but not from the MI.
Received: 30 June 1997 / Accepted: 2 October 1997 相似文献
79.
Embryonic development of four different subsets of cholinergic neurons in rat cervical spinal cord 总被引:1,自引:0,他引:1
P E Phelps R P Barber L A Brennan V M Maines P M Salvaterra J E Vaughn 《The Journal of comparative neurology》1990,291(1):9-26
The developmental stage at which a neuron becomes committed to a neurotransmitter phenotype is an important time in its ontogenetic history. The present study examines when choline acetyltransferase (ChAT) is first detected within each of four different subsets of cholinergic neurons previously identified in the cervical enlargement of the spinal cord: namely, motor neurons, partition cells, central canal cluster cells, and dorsal horn neurons. By examining the temporal sequence of embryonic development of these cholinergic neurons, we can infer the relationships between ChAT expression and other important developmental events. ChAT was first detected reliably on embryonic day 13 (E13) by both biochemical and immunocytochemical methods, and it was localized predominantly within motor neurons. A second group of primitive-appearing ChAT-positive cells was detected adjacent to the ventricular zone on E14. These neurons seemed to disperse laterally into the intermediate zone by E15, and, on the basis of their location, were tentatively identified as partition cells. A third group of primitive ChAT-immunoreactive cells was detected on E16, both within and around the ventral half of the ventricular zone. By E17, some members of this "U"-shaped group appeared to have dispersed dorsally and laterally, probably giving rise to dorsal horn neurons as well as dorsal central canal cluster cells. Other members of this group remained near the ventral ventricular zone, most likely differentiating into ventral central canal cluster cells. Combined findings from the present study and a previous investigation of neurogenesis (Phelps et al.: J. Comp. Neurol. 273:459-472, '88), suggest that premitotic precursor cells have not yet acquired the cholinergic phenotype because ChAT is not detectable until after the onset of neuronal generation for each of the respective subsets of cholinergic neurons. However, ChAT is expressed in primitive bipolar neurons located within or adjacent to the germinal epithelium. Transitional stages of embryonic development suggest that these primitive ChAT-positive cells migrate to different locations within the intermediate zone to differentiate into the various subsets of mature cholinergic neurons. Therefore, it seems likely that spinal cholinergic neurons are committed to the cholinergic phenotype at pre- or early migratory stages of their development. Our results also hint that the subsets of cholinergic cells may follow different migration routes. For example, presumptive partition cells may use radial glial processes for guidance, whereas dorsal horn neurons may migrate along nerve fibers of the commissural pathway. Cell-cell interactions along such diverse migratory pathways could play a role in determining the different morphological, and presumably functional, phenotypes expressed by spinal cholinergic neurons. 相似文献
80.
胶质源性神经营养因子对脊髓损伤后前角运动神经元的保护作用 总被引:13,自引:2,他引:11
目的 :探讨胶质细胞源性神经营养因子 (GDNF)对脊髓损伤后运动神经元的保护作用。 方法 :大鼠分为假手术组、生理盐水 (NS)组和 GDNF组 ,改良 Allen法撞击致伤 T1 2 脊髓 ,蛛网膜下腔分别给予 NS和 GDNF,分别取不同时间的伤段脊髓进行切片 ,应用酶组织化学染色方法显示脊髓前角外侧核运动神经元中胆碱酯酶 (Ch E)和酸性磷酸酶 (ACP)活性 ,并结合计算机进行图像分析。结果 :GDNF组较 NS组 Ch E活性显著增加 ,ACP活性显著降低 ;2 1d时 NS组的 ACP及 Ch E活性均高于及低于假手术组 ;GDNF组与假手术组 Ch E和 ACP活性差别不显著。 结论 :GDNF对脊髓损伤后的前角外侧核运动神经元有一定的保护作用 相似文献