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61.
c-Jun氨基末端激酶(c-Jun N-terminal kinases,JNKs)为丝裂原活化蛋白激酶(mitogen activated protein kinase,MAPK)超家族之一,其参与胚胎发育、免疫反应、及细胞的生长、分化、增殖等多种生理过程,同时也参与了许多病理过程。近期研究表明其在脑缺血性损伤神经元死亡过程中起重要调控作用。现就其相关研究进展作一综述。 相似文献
62.
目的:研究临床路径在大肠癌手术患者中的应用效果。方法:选择广东省江门地区某三甲医院2006年7月至2007年12月间实施临床路径的大肠癌手术患者192例作为实验组,对照组选择该院2005年1月至2006年6月间未实施临床路径按常规模式实施的大肠癌手术患者174例,比较两组患者在住院日、住院费用、患者满意度等方面有无差异性。结果:实验组患者的平均住院日、住院费用等方面明显低于对照组(P<0.01),患者满意度优于对照组(P<0.01)。结论:按临床路径对大肠癌手术患者实施围手术期诊疗护理计划,可减少患者平均住院日,降低住院费用,提高医疗护理服务质量及患者满意度,为进一步扩大临床路径的临床应用范围提供实验数据。 相似文献
63.
Hyung Bin Park Mihee Koh Se Hyun Cho Brian Hutchinson Bonghee Lee 《Journal of orthopaedic research》2005,23(6):1419-1424
The anterior cruciate ligament (ACL) serves as the primary restraint to anterior tibial translation. In addition to this biomechanical function, the ACL appears to have a function in neuromuscular control. This hypothesis was formulated after the discovery of mechanoreceptors within the ACL. The full somatosensory pathway from the ACL to the cerebrum has yet to be elucidated. In order to map this sensory pathway, we conducted a viral trans-synaptic tracing experiment using the neurotropic pseudorabies virus (PRV). The pseudorabies virus was injected into the ACL of rats and allowed to replicate and spread trans-synaptically for 6-7 days. The brain and spinal cord of each sacrificed rat was then removed and processed immunohistochemically to detect the presence of PRV. PRV-immunoreactive neurons were found to be localized in several different regions from the spinal cord to the cerebrum. Four nuclei in the reticular formation of the brain stem demonstrated strong positive labeling: the mesencephalic reticular nucleus, magnocellular reticular nucleus, paragigantocellular reticular nucleus, and gigantocellular reticular nucleus. This finding suggests that the nerve endings of the rat ACL project into the cerebrum and that the reticular formation may play an important role in the afferent pathway of those nerve endings. 相似文献
64.
José Manuel Valdueza Loris Cristante Jörg Freitag Christian Hagel Hans-Dietrich Herrmann 《Neurosurgical review》1995,18(4):273-275
The clinical, neuroradiological, and histological findings of an adult patient suffering from malignant optic glioma is reported. Rapid visual deterioration was misdiagnosed for several months until biopsy confirmed the tumor. The patient died despite radiation therapy nine months after first symptoms. Our presentation will focus on the problems of diagnosing and establishing therapeutic procedures in this rare malignant neoplasm. 相似文献
65.
Binding of a specific dopamine D1 receptor antagonist,125I-SCH 23982, was measured in rat brain sections by quantitative autoradiography at various time intervals, following a knife cut through the striatonigral pathway. Twenty-four hours after lesioning, accumulations of D1 receptor binding sites were found in sagittal sections both rostral and caudal to the lesion site. No other regions studied (caudate-putamen, nucleus accumbens, olfactory tubercle, and substantia nigra pars reticulata) showed any change in D1 receptor binding 24h after the lesion. In brain sections obtained 10 days after lesioning, only the substantia nigra pars reticulata had a significant decrease in D1 receptors ipsilateral to the lesion. These findings suggest the possibility of a presence of bidirectional axonal transport of D1 receptors in rat striatonigral pathway. 相似文献
66.
The effects of anesthesia on otoacoustic emissions 总被引:4,自引:0,他引:4
Noam Harel Akinobu Kakigi Haruo Hirakawa Richard J. Mount Robert V. Harrison 《Hearing research》1997,110(1-2):25-33
We have measured transient-evoked and distortion-product otoacoustic emissions (OAEs) in the chinchilla and compared them in the awake and anesthetized animal (using either ketamine or barbiturate agents). We report a significant increase in OAE amplitudes during anesthesia, particularly using ketamine. These effects are most evident for transient-evoked otoacoustic emissions (TEOAEs) as measured in the non-linear mode. Our data support the hypothesis that tonic activity levels in cochlear efferents may be reduced by anesthetic effects, either directly or indirectly (e.g., by general reductions in descending pathway activity), and that reduced cochlear efferent activity will result in the observed increase of OAE amplitudes. 相似文献
67.
目的:观察肝素对患感染性疾病的新生儿组织因子途径抑制物(TFPI)的影响。方法:采用酶联免疫吸附试验(ELISA)法检测了32例患感染性疾病的新生儿在使用肝素前和使用肝素后30~45分钟、6小时血浆TFPI的变化,并与患儿对照组、正常对照组及文献进行比较。结果:患儿治疗组使用肝素后30~45分钟血浆TFPI水平明显增高(t=3.953,P<0.001),6小时血浆TFPI又几乎降至用药前水平(t=0.141,P<0.05)。结论:新生儿对肝素的反应与成人不同。 相似文献
68.
Radiofrequency Ablation of Concealed Left Free-Wall Accessory Pathways Without Coronary Sinus Catheterization: 总被引:1,自引:0,他引:1
JOSEP BRUGADA M.D. IGNACIO GARCIA-BOLAO M.D. MARCIO FIGUEIREDO M.D. MARTÍ PUIGFEL M.D. MARIONA MATAS R.N. FRANCISCO NAVARRO-LÓPEZ M.D. 《Journal of cardiovascular electrophysiology》1997,8(3):249-253
Ablation of Concealed Accessory Pathways. Introduction: Feasibility of radiofrequency (RF) ablation using a two-catheter technique without coronary sinus catheterization was studied in 100 consecutive patients with a single concealed left free-wall accessory path-way.
Methods and Results: Tachycardia was induced by electrical stimulation in the right atrium/right ventricle, and the presence of a concealed left free-wall accessory pathway was suggested electrocardiographically (negative P wave in leads I and/or a VL during orthodromic tachycardia) or by earlier atrial activation in the pulmonary artery compared to the high right atrium. Mapping of the mitral annulus was performed during right ventricular pacing or orthodromic tachycardia, and RF energy was applied at the site with the earliest retrograde atrial activation. Ablation was considered effective if tachycardia could not be induced, and if VA dissociation or exclusive retrograde nodal conduction was observed. Ablation was initially successful in 98 of 100 patients. Mean number of radiofrequency pulses were 3.2 ± 2. Mean fluoroscopy time and total procedure time was 14 ± 9 and 107 ± 32 minutes, respectively. There were no complications related to the procedure. At a mean follow-up of 22 ± 13 months, two patients experienced tachycardia recurrence and required a second procedure, which was successful.
Conclusions: Our results suggest that RF catheter ablation of concealed left free-wall accessory pathways can be safely, effectively, and rapidly performed using a simplified two-catheter technique with no need for coronary sinus catheterization. 相似文献
Methods and Results: Tachycardia was induced by electrical stimulation in the right atrium/right ventricle, and the presence of a concealed left free-wall accessory pathway was suggested electrocardiographically (negative P wave in leads I and/or a VL during orthodromic tachycardia) or by earlier atrial activation in the pulmonary artery compared to the high right atrium. Mapping of the mitral annulus was performed during right ventricular pacing or orthodromic tachycardia, and RF energy was applied at the site with the earliest retrograde atrial activation. Ablation was considered effective if tachycardia could not be induced, and if VA dissociation or exclusive retrograde nodal conduction was observed. Ablation was initially successful in 98 of 100 patients. Mean number of radiofrequency pulses were 3.2 ± 2. Mean fluoroscopy time and total procedure time was 14 ± 9 and 107 ± 32 minutes, respectively. There were no complications related to the procedure. At a mean follow-up of 22 ± 13 months, two patients experienced tachycardia recurrence and required a second procedure, which was successful.
Conclusions: Our results suggest that RF catheter ablation of concealed left free-wall accessory pathways can be safely, effectively, and rapidly performed using a simplified two-catheter technique with no need for coronary sinus catheterization. 相似文献
69.
M. P. Nieto-Bona L. M. Garcia-Segura I. Torres-Aleman 《Journal of neuroscience research》1993,36(5):520-527
Insulin-like growth factor I (IGF-I) and its receptor are expressed in functionally related areas of the rat brain such as the inferior olive and the cerebellar cortex. A marked decrease of IGF-I levels in cerebellum is found when inferior olive neurons are lesioned. In addition, Purkinje cells in the cerebellar cortex depend on this growth factor to survive and differentiate in vitro. Thus, we consider it possible that IGF-I forms part of a putative trophic circuitry encompassing the inferior olive and the cerebellar cortex and possibly other functionally connected areas. To test this hypothesis we have studied whether IGF-I may be taken up, transported, and released from the inferior olive to the cerebellum. We have found that 125I-IGF-I is taken up by inferior olive neurons in a receptor-mediated process and orthogradely transported to the cerebellum. Thus, radioactivity found in the cerebellar lobe contralateral to the injection site in the inferior olive was immunoprecipitated by an anti-IGF-I antibody, co-eluted with 125I-IGF-I in an HPLC column, and co-migrated with 125I-IGF-I in an SDS-urea polyacrylamide gel electrophoresis. Time-course studies indicated that orthograde axonal transport is relatively rapid since 30 min after the injection, radiolabeled IGF-I was already detected in the contralateral cerebellum. Furthermore, transport of IGF-i from the inferior olive is specific since when 125I-neurotensin was injected in the inferior olive or when 125I-IGF-I was injected in the pontine nucleus, no radiactivity was found in the contralateral cerebellum. In addition, no specific transport of 125I-IGF-I was found in climbing fiber-deafferented rats or when excess unlabeled IGF-I was co-injected with 125I-IGF-I. We next studied whether IGF-I is released by inferior olive neurons. We found that the release of IGF-I from cerebellar slices of normal rats was significantly greater in response to depolarizing stimuli than that from slices obtained of climbing fiber-deafferented animals. Indeed, in vitro release of IGF-I in response to KCI or veratridine was almost completely abolished in the latter. These data suggest that IGF-I is taken up by inferior olive neurons through IGF-I receptors and transported to the cerebellum through their axons without any major modification. Moreover, the release of IGF-I from the cerebellum after depolarization depends on the presence of climbing fiber afferents. Altogether these results indicate that the olivo-cerebellar pathway is able to take up, orthogradely transport, and release IGF-I. Since a similar process has been described in the visual system for basic fibroblast growth factor (bFGF), we propose that IGF-I, bFGF, and possibly other growth factors may constitute afferent trophic signals involved in plastic mechanisms within specific neural circuitries. © 1993 Wiley-Liss, Inc. 相似文献
70.
本文报告两例持续性交界区反复性心动过速(PJRT)患者,应用导管射频消融术治疗,成功地阻断了位于后间隔具有递减传导特性的稳若旁路.随访7~10个月.病人无心动过速发作,提示导管射频消融术是治疗PJRT的有效方法. 相似文献