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91.
背景:目前关于氨基葡萄糖的研究多集中于对膝骨关节炎的治疗作用,但关于其对膝骨关节炎患者外周血中软骨代谢相关基因影响的研究有限。目的:观察氨基葡萄糖胶囊对膝骨关节炎的治疗效果及对软骨代谢相关基因表达的影响。方法:选取2017年3月至2019年2月郑州大学附属郑州中心医院收治的90例膝骨关节炎患者,另选取同期医院体检中心收入的40例健康受试者,检测并对比健康受试者与膝骨关节炎患者治疗前外周血单个核细胞中软骨寡聚基质蛋白、Ⅱ型胶原纤维α1、聚糖蛋白、特异性组织抑制物3基因表达水平。采用随机数表法将膝骨关节炎患者分为常规组和研究组,分别给予双氯芬酸钠缓释片、双氯芬酸钠缓释片+氨基葡萄糖胶囊治疗12周,对比治疗前后2组外周血单个核细胞中各基因表达水平、Lequesne指数,统计治疗期间2组不良反应发生情况。结果与结论:①与健康受试者比较,膝骨关节炎患者外周血单个核细胞中软骨寡聚基质蛋白、特异性组织抑制物3 mRNA相对表达量升高(P<0.05),Ⅱ型胶原纤维α1、聚糖蛋白mRNA相对表达量降低(P<0.05);②治疗前研究组和常规组外周血单个核细胞中各基因表达水平比较,差异均无显著性意义(P>0.05);治疗后2组外周血单个核细胞中软骨寡聚基质蛋白、特异性组织抑制物3 mRNA相对表达量均低于治疗前,且研究组低于常规组(P<0.05);治疗后2组外周血单个核细胞中Ⅱ型胶原纤维α1、聚糖蛋白mRNA相对表达量均高于治疗前,且研究组高于常规组(P<0.05);③治疗前研究组和常规组Lequesne指数比较,差异均无显著性意义(P>0.05);治疗后2组Lequesne指数均低于治疗前,且研究组低于常规组(P<0.05);④研究组和常规组不良反应发生率比较,差异均无显著性意义(P>0.05);⑤结果表明,氨基葡萄糖胶囊可有效改善膝骨关节炎患者临床症状且安全可靠,可能通过抑制软骨寡聚基质蛋白、特异性组织抑制物3基因表达,促进Ⅱ型胶原纤维α1、聚糖蛋白基因表达实现的。 相似文献
92.
甲壳素短纤维增强聚己内酯复合材料的制备及生物学评价 总被引:1,自引:0,他引:1
用共混法制备甲壳察短纤维增强聚己内酯复合材料,并对纯聚己内酯和甲壳察短纤维增强聚己内酯复合材料进行体外细胞毒性和生物相容性评价,为临床应用提供有价值的实验依据。对该两种材料进行体外细胞毒性试验、急性全身毒性试验、溶血试验、热源试验和过敏试验。结果显示受试材料最终细胞毒性级为0级,对细胞生长和增殖无明显抑制作用,材料中不存在潜在致敏性物质,浸提液无溶血反应和急性全身毒性反应,无热源反应,表明该复合材料具有良好的细胞和组织相容性,其作为胸壁缺损修补材料应用于临床具有可行性和安全性。 相似文献
93.
Ruthenium red has been shown to have a positive inotropic effect on isolated perfused hearts. The cellular mechanism of this action is not clear. Ruthenium red is able to block the Ca2+ release channel in isolated sarcoplasmic reticulum (SR) vesicle and reconstituted channel preparations. However, the effect of ruthenium red on SR Ca2+ release has not been studied in skinned cardiac muscle preparations. In the present study we investigated the actions of ruthenium red on both the characteristics of force generation by the contractile apparatus and Ca2+ release from the SR in chemically skinned rat papillary muscle. Ruthenium red (2 and 10 M) significantly increased the Ca2+ sensitivity of the contractile apparatus (decreasing Ca2+ required for the half-maximal response from 1.56±0.04 M to 1.46±0.05 M) but had no effect on the maximal Ca2+-activated force in triton X-100 treated fibers. This result may suggest one explanation for the positive inotropic effect of ruthenium red on the heart. On the other hand, ruthenium red had no significant effect on either caffeine-induced Ca2+ release or Ca2+-induced Ca2+ release from the SR in saponin-skinned muscle fibers. Lack of a blocking effect on SR Ca2+ release by ruthenium red in skinned fibers suggests that the SR Ca2+ channels in intact preparations have characteristics that are different from those of either vesicular or reconstituted channel preparations. 相似文献
94.
皮质—网状—脊髓通路——HRP法结合溃变电镜法研究 总被引:2,自引:1,他引:2
用HRP逆行标记法结合溃变电镜技术,观察了12只大鼠的蓝斑,外侧网状核,中缝大核,巨细胞网状核在旁正中网状核中皮质纤维终末的超微结构及其与网状脊髓神经元的突触联系。损伤皮质感觉运动区的各例动物,均出现两种溃变型,电子致密型和微丝增生型。前者为皮质的主要溃变型,分布于各核;后者出现很少,只见于外侧网状核。电子致密型终扣有大小两种,大终扣少,有含圆形清亮型小泡,多形清亮型小泡,清亮型和颗粒型小泡并存的 相似文献
95.
Norihiro Suzuki Jan Erik Hardebo Jan K hrstr m Christer Owman 《Neuroscience letters》1989,100(1-3):123-129
Galanin (GAL)-positive nerve fibers in rat cerebral vessels were demonstrated by immunohistochemistry, and their origin in the trigeminal ganglia and pathway in the nasociliary nerve to the vessels was shown by retrograde tracer technique and nerve transection. Some fibers in the vertebrobasilar system appear to originate in extracranial sources. With the antiserum used only few GAL fibers could be seen in the vessels, mostly in the vertebrobasilar system. In neonatally sympathectomized animals a rich network could be visualized in most pial arteries - still particularly in the vertebrobasilar system - probably as a result of a diminished competition for nerve growth factor. No vasomotor effect of GAL could be detected in isolated segments of pial arteries, neither in normal nor in sympathectomized animals, which rules out a direct postsynaptic effect on vascular tone. GAL did not display prejunctional modulatory action on the adrenergic nerves present in the vascular preparations. A sensory function of GAL is discussed. 相似文献
96.
Cardiac ankyrin repeat protein (CARP), which is structurally characterized by the presence of four ankyrin repeat motifs in its central region, is believed to be localized in the nucleus and to participate in the regulation of cardiac-specific gene expression in cardiomyocytes. However, we recently found that CARP was induced in skeletal muscle by denervation, leading us to speculate that CARP may be induced under some pathological conditions. In the present study, we immunohistochemically analyzed the expression of CARP in 11 cases of spinal muscular atrophy (SMA) and 14 cases of congenital myopathy. In SMA, CARP was expressed selectively in severely atrophic myofibers, suggesting that CARP expression may reflect the status of muscle atrophy. Furthermore, in the congenital myopathies, the expression patterns of CARP were distinct among the subtypes, which included nemaline myopathy, myotubular myopathy, central core disease, and congenital fiber type disproportion. Although CARP was preferentially expressed in severely damaged myofibers in nemaline myopathy, it was not detected in central core disease. These findings suggest that immunohistochemical evaluation of CARP may be helpful in the diagnosis of SMA and the congenital myopathies. 相似文献
97.
Ervilha UF Farina D Arendt-Nielsen L Graven-Nielsen T 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,164(2):215-224
This study investigated the effect of muscle pain on muscle activation strategies during dynamic exercises. Ten healthy volunteers performed cyclic elbow flexion/extension movements at maximum speed for 2 min after injection of (1) hypertonic (painful) saline in the biceps brachii, (2) hypertonic saline in both biceps brachii and triceps brachii, and (3) isotonic (nonpainful) saline in the biceps brachii muscle. Surface electromyographic (EMG) signals were collected from the upper trapezius, biceps brachii, triceps brachii, and brachioradialis muscles (to estimate EMG amplitude) and with an electrode arrays from biceps brachii (to estimate muscle fiber conduction velocity [CV]). In all conditions, the acceleration of the movement decreased throughout the exercise, and kinematic parameters were not altered by pain. With respect to the control condition, pain induced a decrease of the biceps brachii (mean ± SE, –23±4%) and brachioradialis (–10±0.4%) integrated EMG (IEMG) in the beginning of the exercise, and an increase (45±3.5%) of the upper trapezius IEMG at all time points during the exercise. The biceps brachii IEMG decreased over time during the nonpainful exercises (–11±0.6%) while it remained constant in the painful condition. Biceps brachii CV decreased during painful conditions (–12.8±2.2%) while it remained constant during the nonpainful condition. In conclusion, muscle pain changes the motor control strategy to sustain the required dynamic task both in the relative contribution between synergistic muscles and in the motor unit activation within the painful muscle. Such a changed motor strategy may be highly relevant in models of occupational musculoskeletal pain conditions. 相似文献
98.
应用WGA-HRP顺行轴突运输研究大鼠视前内侧区传出性神经纤维投射。结果表明:视前内侧区的上行投射向嘴侧经斜角带进入外侧隔核;经髓纹进入缰核;经无名质进入杏仁前区及经终纹进入杏仁内侧核,另有标记纤维经内侧前脑束向外下行,经视束上方进入杏仁内侧核。下行投射经内侧前脑束进入下丘脑室旁核、外侧区、内侧核、后核、弓状核、乳头体前腹核和乳头体上核。继续向尾侧,标记纤维进入中脑腹侧背盖区,并投射到中缝正中核及中缝背核。 相似文献
99.
W. L. Kerr R. J. Baskin Y. Yeh 《Pflügers Archiv : European journal of physiology》1990,416(6):679-688
Microstructural features of relaxed, skinned muscle fibers compressed with polyvinylpyrollidone were examined by optical diffraction ellipsometry. This technique is sensitive to the optical anisotropy within the muscle, including that due to intrinsic properties of the protein molecules as well as that due to the regular arrangement of proteins in the surrounding medium. The change in polarization state of light after interacting with the muscle is described by the differential field ratio (DFR) and birefringence (n). Compression of single fibers (sarcomere length = 2.6 m) with 0%–21% polyvinylpyrrolidone caused an increase of up to 23% and 31% for DFR and n, respectively. The largest increase in both parameters occurred at intermediate sarcomere lengths. Theoretical modelling of the results suggest that the average S-1 tilt angle may be reduced upon compression of the filament lattice. This is supported by experiments in which S-1 was enzymatically cleaved with -chymotrypsin. Separate experiments comparing fibers with intact membranes and skinned fibers compressed to an equivalent lattice spacing showed little difference in DFR or n. 相似文献
100.
Investigation of eye movement-related activities and photic responsiveness using behaving cats demonstrated distinctive representations of eye movement signals in different areas of the lateral suprasylvian cortex: visual reafference in the medial bank of the middle suprasylvian sulcus and non-visual signals (proprioceptive reafference or efference copy) in the lateral bank. 相似文献