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81.
本研究采用SDS凝胶电泳方法从人脊神经前根中分离出人脊髓前角运动神经元特有的蛋白—190KD。将该蛋白作为抗原,免疫BALB/c小鼠,经杂交瘤技术,获得了抗190KD蛋白的单克隆抗体。免疫细胞化学检测表明,190KD单抗与脊髓灰质前角神经元、前根及肌支发生阳性反应。实验结果提示,190KD蛋白分布在脊髓运动神经元胞体及脊神经的前根和肌支纤维中。 相似文献
82.
Gustavo Arruda Viani Juliana Fernandes Pavoni Ligia Issa De Fendi 《Reports of Practical Oncology and Radiotherapy》2021,26(2):218
BackgroundThe aim of this study was to evaluate the effectiveness of prophylactic corticosteroids to prevent pain flare (PF) in bone metastases treated with radiotherapy performing a meta-analysis of randomized clinical trials (RCT).Materials and methodsRCTs were identified on Medline, Embase, the Cochrane Library, and the proceedings of annual meetings through June 2020. We followed the PRISMA and MOOSE guidelines. A meta-analysis was performed to assess if corticosteroids reduce the PF, pain progression, and the mean of days with PF compared with the placebo. A p-value < 0.05 was considered significant.ResultsThree RCTs with a total of 713 patients treated were included. The corticosteroids reduced the occurrence of early PF 20.5% (51/248) versus 32% (80/250) placebo, OR = 0.55 (95% CI: 0.36–0.82, p = 0.002). The mean days of PF were reduced to 1.6 days (95% CI: 1.3–1.9, p = 0.0001). Prophylactic corticosteroids had more patients with no PF and no pain progression, OR = 1.63 (95% CI: 1.14–2.32, p = 0.007). No significant corticosteroids effect was observed for pain progression (p = ns) and late PF occurrence (p = ns).ConclusionProphylactic corticosteroids reduced the incidence of early PF, the days with PF, resulting in a superior rate of patients with no PF and no pain progression, but with no significant benefit for reducing pain progression or late PF occurrence. 相似文献
83.
Leonid B. Reshko Jeremy T. Gaskins Craig L. Silverman Neal E. Dunlap 《Reports of Practical Oncology and Radiotherapy》2021,26(3):325
BackgroundStereotactic body radiation therapy (SBRT) as a form of noninvasive treatment that is becoming increasingly used to manage cancers with adrenal gland metastases. There is a paucity of data on safety and efficacy of this modality. The aim of the study was to evaluate the safety and efficacy of adrenal gland SBRT in oligometastatic and oligoprogressive disease.Materials and methodsIn this retrospective study, we performed a single-institution analysis of 26 adrenal lesions from 23 patients with oligometastatic or oligoprogressive disease treated from 2013 to 2019 with the goal of achieving durable local control. Palliative cases were excluded. Radiation dosimetry data was collected. Kaplan Meier product estimator and Cox proportional hazards regression analysis were used for statistical analysis.ResultsThe median dose was 36 Gy in 3 fractions (range: 24–50 Gy and 3–6 fractions) with a median biologically effective dose (BED10) of 72 (range: 40–100). 1-year local control rate was 80% and median local control was not achieved due to a low number of failures. 1- and 2-year overall survival rates were 66% and 32%. Toxicity was mild with only one case of grade 2 nausea and no grade 3–5 toxicity. Higher neutrophil to lymphocyte ratio was associated with worse overall survival and a trend toward worse progression-free survival. In addition, worse performance status and lower BED10 were associated with worse survival. No such association could be shown for primary tumor location, histology, size or stage.ConclusionAdrenal SBRT for oligometastatic or oligoprogressive disease is a safe and effective form of treatment. 相似文献
84.
Kazuo Kusano Takashi Hirai Kenichi Shinomiya 《Biochemical and biophysical research communications》2010,393(4):812-195
Neutrotrophin-3 (NT3) plays a protective role in injured central nervous system tissues through interaction with trk receptors. To enhance the regeneration of damaged tissue, a combination therapy with cell transplantation and neurotrophins has been under development. We examined whether the transplantation of neural progenitor cells (NPCs) secreting NT3/D15A, a multi-neurotrophin with the capacity to bind both trkB and trkC, would enhance the repair of damaged tissues and the functional recovery in a chronic phase of spinal cord injury. The cultured NPCs with lentiviral vector containing either GFP or NT3/D15A were transplanted into the contused spinal cord at 6 weeks after the initial thoracic injury. Eight weeks after the transplantation, the NT3/D15A transplants displayed better survival than the GFP transplants, and they exhibited enhanced myelin formation and partial improvement of hindlimb function. Our study revealed that NT3/D15A produced positive effects in injured spinal cords even in the chronic phase. These effects suggest an enhanced neurotrophin-trk signaling by NT3/D15A. 相似文献
85.
Harri Sievänen 《Archives of biochemistry and biophysics》2010,503(1):146-1747
Long-term immobilization is known to result in substantial bone loss. The present review examined the existing evidence for deterioration of bone structure during long-term disuse in humans. Paralysis due to spinal cord injury, long-term exposure to microgravity in space or tightly restricted mobility during bed rest provide reasonable models to assess the influence of immobilization on bone structure. Expectedly, the duration of immobilisation was the major determinant of bone loss, but irrespective of whether the skeletal unloading was due to irrecoverable paralysis, long-term spaceflight or bed rest, the mean pattern of structural deterioration of bone, mainly manifest as substantial cortical thinning and trabecular bone loss, was quite similar. However, skeletal responses to disuse can be highly variable between individuals. Apparently the relative decline in individual’s bone loading in relation to loading prior to immobilization accounts for inter-individual variation. 相似文献
86.
Jo S 《Bio Systems》2007,90(3):750-768
This paper proposes a human mimetic neuro-musculo-skeletal model to simulate the recovery reactions from perturbations during walking. The computational model incorporates nonlinear viscoelastic muscular mechanics, supraspinal control of the center-of-mass, spinal pattern generator including muscle synergy network, spinal reflexes, and long-loop reflexes. Especially the long-loop reflexes specify recovery strategies based on the experimental observations [Schillings, A.M., van Wezel, B.M.H., Mulder, T.H., Duysen, J., 2000. Muscular responses and movement strategies during stumbling over obstacles. J. Neurophysiol. 83, 2093–2102; Eng, J.J., Winter, D.A., Patla, A.E., 1994. Strategies for recovery from a trip in early and late swing during human walking. Exp. Brain Res. 102, 339–349]. The model demonstrates two typical recovery strategies, i.e., elevating and lowering strategies against pulling over a swing leg. Sensed perturbation triggers a simple tonic pulse from the cortex. Depending on the swing phase, the tonic pulse activates a different compound of muscles over lower limbs. The compound induces corresponding recovery strategies. The reproduction of principal recovery behaviors may support the model's proposed functional and/or anatomical correspondence. 相似文献
87.
The spino-occipital nerve (SO) and ventral rami of the spinal nerves (SV) in 10 tetraodontiform families and 5 outgroup taxa
were examined, with special reference to pectoral and pelvic fin muscle innervation. Compared with the outgroup taxa, tetraodontiforms
were characteristic in having SO3 + SV1 (SO3 in tetraodontids) that gave off several lateral subbranches to the pectoral fin
base and SO participation in infracarinalis anterior innervation. SO and SV1 were connected with one another (6 patterns)
before entering the pectoral fin muscles in most species, including the outgroup taxa, resulting in the participation of SV1
in the innervation of almost all of the pectoral fin muscles. SO3 + SV1 was present in all tetraodontiforms (except in 2 tetraodontids
having only SO3) and the outgroup taxa, an upper dorsal branch uniformly extending dorsally into the pectoral fin base. The
pectoral fin base also received a branch ventrally, but its identity differed (participation or nonparticipation of SV2).
SV1 alone constituting the branch was a derived condition occurring in Aracanidae, Ostraciidae, Tetraodontidae, Diodontidae,
and Molidae. No strong characters supporting a tetraodontiform sister group were recognized among the spino-occipital nerve
and ventral rami of spinal nerves. 相似文献
88.
Mesenchymal Stem Cells from Rat Bone Marrow Downregulate Caspase-3-mediated Apoptotic Pathway After Spinal Cord Injury in Rats 总被引:6,自引:0,他引:6
Mesenchymal stem cells have been intensively studied for their potential use in reparative strategies for neurodegenerative
diseases and traumatic injuries. We used mesenchymal stem cells (rMSC) from rat bone marrow to evaluate the therapeutic potential
after spinal cord injury (SCI). Immunohistochemistry confirmed a large number of apoptotic neurons and oligodendrocytes in
caudal segments 2 mm away from the lesion site. Expression of caspase-3 on both neurons and oligodendrocytes after SCI was
significantly downregulated by rMSC. Caspase-3 downregulation by rMSC involves increased expression of FLIP and XIAP in the
cytosol and inhibition of PARP cleavage in the nucleus. Animals treated with rMSC had higher Basso, Beattie, Bresnahan (BBB)
locomotor scoring and better recovery of hind limb sensitivity. Treatment with rMSC had a positive effect on behavioral outcome
and histopathological assessment after SCI. The ability of rMSC to incorporate into the spinal cord, differentiate and to
improve locomotor recovery hold promise for a potential cure after SCI.
Special issue in honor of Naren Banik. 相似文献
89.
目的利用成年SD大鼠脊髓损伤原代培养的反应性星形胶质细胞模型,探讨内皮素-1(ET1)与反应性星形胶质细胞增殖之间的关系。方法建立成年SD大鼠脊髓损伤原代培养的反应性星形胶质细胞模型,用100 n M ET1和5μM BQ788(内皮素受体B的拮抗剂)处理反应性星形胶质细胞48 h,通过免疫荧光的方法对各实验组中星形胶质细胞的标记分子Vimentin及Brdu进行检测,以确定ET1对反应性星形胶质细胞增殖的影响。结果 ET1组中星形胶质细胞的数量明显增加,Brdu阳性细胞占星形胶质细胞的平均百分比(19.41%)高于正常对照组(3.28%,P0.01);而ET1+BQ788组中Brdu阳性细胞数占星形胶质细胞的平均百分比为10.38%,明显低于ET1组(19.41%,P0.01)。结论在成年SD大鼠脊髓损伤原代培养的反应性星形胶质细胞模型中,ET1可刺激反应性星形胶质细胞的增殖,ET1受体endothelin B的拮抗剂BQ788可有效抑制ET1对反应性星形胶质细胞的促增殖效应。 相似文献