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21.
大鼠脊髓慢性压迫及减压后神经细胞凋亡及其相关基因的表达 总被引:15,自引:3,他引:12
目的:观察慢性压迫性脊髓损伤后及减压后神经细胞凋亡和Bcl-2mRNA,P53mRNA,CASPASE-3神经功能恢复的影响。方法:将55只同龄Wistar大鼠,置入后路渐进式压迫装置,制作成慢性压迫性脊髓损伤模型。随机分为假手术对照组(A组5只),慢性脊髓压迫组(B组25只),减压组(C组25只)。应用原原位末端脱氧核糖核苷酸转移酶介导dUTP标记(TUNEL)技术及原位杂交检测方法,观察各组细胞凋亡率及细胞凋亡相关基因Bcl-2mRNA、P53mRNA、CASPASE-3在慢性压迫性脊髓损伤后及减压后的表达,分别于损伤后及减压后1、3、7、14、28d对慢性脊髓损伤区进行细胞凋亡及原位杂交检测。结果:A、B、C三组均发现神经细胞凋亡及细胞凋亡相关基因Bcl-2mRNA、P53mRNA,CASPASE-3的表达,A、B、C三组细胞凋亡率及阳性细胞灰度值比较,差异有显著性意义(P<0.05)。阳性细胞表达程度与细胞凋亡的减少及神经功能的恢复相一致。结论:慢性压迫性脊髓损伤可导致大量的神经细胞凋亡,同时激活内源性保护机制,使脊髓发生适应性改变,减压可能通过激活此机制而减轻神经细胞凋亡,起到保护作用。 相似文献
22.
改良Richard钉在髋部骨折中的应用 总被引:3,自引:0,他引:3
髋部骨折是常见骨折之一,且逐年增多。多发生于老年人,并发症多,死亡率高。应用Richard钉治疗是目前最佳方法之一。我们将Richard钉进行了改进,一是增加了松质骨螺钉粗螺纹长度;二是根据不同类型的粗隆下骨折,增加了套筒钢板的长度。经52例粗隆间骨折和21例粗隆下骨折患者的临床应用,无死亡,无髋内翻及机械装置并发症的发生。术后病人无需外固定,可早期床上及下地活动。经随访8~38个月,平均随访时间15.6个月,骨折全部愈合。我们认为改良Richard钉是治疗髋部粗隆间和粗隆下骨折更为理想的内固定装置。 相似文献
23.
肩关节脱位手法整复的流派及发展动态 总被引:8,自引:6,他引:2
肩关节脱位指的是肩肱(或称盂肱)关节脱位,临床上十分常见,肩关节脱位通常采取手法整复,疗效确切,手法整复研究也较多,笔者参阅有关文献资料,结合自己的临床体会,对国内肩关节脱位的手法整复流派和发展动态做一整理,与同仁共飨。 相似文献
24.
25.
Illana Gozes John Glowa Douglas E. Brenneman Susan K. McCune Eric Lee Heiner Westphal 《Journal of molecular neuroscience : MN》1993,4(3):185-193
The molecular mechanisms responsible for behavior are largely unknown. A state of the art model, paving the path from genes
to behavior, is offered by transgenic animals. Candidate molecules are classic neuropeptides, such as vasoactive intestinal
peptide (VIP). Transgenic mice harboring a chimeric VIP gene driven by the polyoma promoter were produced. Behavioral studies
revealed learning impairment and prolonged retardation in memory acquisition in the genetically altered animals. Furthermore,
reduced performance was observed when the male transgenic mice were tested for sexual activity in the presence of receptive
females. Surprisingly, radioimmunoassays showed an approx 20% decrease in the VIP content of the transgenic mice brains. To
directly assess genetically reduced VIP content as a cause for learning impairment, transgenic mice carrying diphtheria toxia-encoding
sequences driven by the rat VIP promoter were created. These animals had reduced brain VIP and exhibited deficiencies in learning
abilities, strongly supporting an important neurobiological function for VIP in vivo. 相似文献
26.
Mihrimah Ozkan Mark Wang Cengiz Ozkan Richard Flynn Sadik Esener 《Biomedical microdevices》2003,5(1):61-67
In this paper, we review optical techniques used for micro-manipulation of small particles and cells in microfluidic devices. These techniques are based on the object's interaction with focused laser light (consequential forces of scattering and gradient). Inorganic objects including polystyrene spheres and organic objects including biological cells were manipulated and switched in and between fluidic channels using these forces that can typically be generated by vertical cavity surface emitting laser (VCSEL) arrays, with only a few mW optical powers. T-, Y-, and multi-layered X fluidic channel devices were fabricated by polydimethylsiloxane (PDMS) elastomer molding of channel structures over photolithographically defined patterns using a thick negative photoresist. We have also shown that this optical manipulation technique can be extended to smaller multiple objects by using an optically trapped particle as a handle, or an optical handle. Ultimately, optical manipulation of small particles and biological cells could have applications in biomedical devices for drug discovery, cytometry and cell biology research. 相似文献
27.
28.
Extrinsic risk factors for compromised blood flow in the vertebral artery: anatomical observations of the transverse foramina from C3 to C7 总被引:2,自引:0,他引:2
Cagnie B Barbaix E Vinck E D'Herde K Cambier D 《Surgical and radiologic anatomy : SRA》2005,27(4):312-316
The vertebral artery (VA) is often involved in the occurrence of complications after spinal manipulative therapy. Due to osteophytes
compressing the VA anteriorly from the uncinate process or posteriorly from the facet complex, the VAs are susceptible to
trauma in the transverse foramina. Such altered anatomical configurations are of major clinical significance, as spinal manipulations
may result in dissection of the VA with serious consequences for the blood supply to the vertebrobasilar region. The purpose
of this study is to describe numerous structural features of the third to seventh cervical vertebrae in order to contribute
to the understanding of pathological conditions related to the VA. The minimal and maximal diameter of 111 transverse foramina
in dry cervical vertebrae were studied. The presence of osteophytes and their influence on the VA were evaluated at the vertebral
body and at the superior and inferior articular facets. The diameter of the transverse foramina increased from C3 to C6, while
the transverse foramina of C7 had the smallest diameter. At all levels the mean dimensions of the left foramina were greater
than those of the right side. Osteophytes from the uncinate process of C5 and C6 vertebrae were found in over 60% of dry vertebrae.
Osteophytes from the zygapophyseal joints were more frequent at C3 and C4 vertebrae. About half of the osteophytes of the
uncinate and of the superior articular process partially covered the transverse foramina. This was less common with those
of the inferior articular facets. Osteophytes covering the transverse foramen force the VAs to meander around these obstructions,
causing narrowing through external compression and are potential sites of trauma to the VAs potentially even leading to dissection.
We strongly advocate that screening protocols for vertebrobasilar insufficiency (VBI) be used prior to any manipulation of
the cervical spine and should include not only extension and rotation but any starting position from which the planned manipulation
will be performed. 相似文献
29.
Summary Gene disruption and gap repair of chromosomal DNA have been frequently employed techniques in yeast genetics. To extend the possibility of using these gene manipulations for larger genomic regions, we have examined the maximal sizes of chromosomal DNA disrupted or repaired in vivo. Here we report a simple, potentially general, method for selectively deleting a 150 kb region, or gap-filling a 100 kb region, in the fission yeast genome. This enables the generation of acentric linear chromosomes by deletion, or the cloning of large functional centromeric DNAs into circular minichromosomes by gap-filling. The fidelity of the resulting gap-filling is high, judging from partial-digestion mapping of gap-repaired DNAs. By analysing a series of such circular minichromosomes, we conclude that only a part of the repetitive centromeric region, including the central domain, is essential for mitotic and meiotic chromosome segregation. Acentric linear chromosomes, although unstable, could be maintained, indicating that it may be possible to construct an acentric vector for large DNA fragments in this organism. 相似文献
30.
The role of expectancy in enhancing or mitigating premenstrual symptoms was examined in 51 mothers of preschoolers. Expectancy was manipulated by providing information either in support of a biological cause for genuine universal mood changes or in support of a psychological cause arising out of negative societal myths. A third group was given no information. Mood, cognitive function, and mother-child interaction were assessed both at midcycle and premenstrually, and the results suggested that expectancy enhances symptoms. The Psychological group lowered their symptom expectations and reported less negative mood premenstrually as well as fewer symptoms at the end of the test month. The other groups reported no change in symptoms and greater premenstrual negative mood than the Psychological group. All groups demonstrated greater task persistence and more positive motherchild interaction during the premenstrual phase.This study is based upon the doctoral dissertation completed in partial fulfillment of the Ph.D. degree from the University of Ottawa. 相似文献