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81.
目的 探讨老年腰椎间盘突出症的特点与手术治疗效果.方法 对62例老人腰椎间盘突出症患者的临床与病理特点进行分析.均行腰椎后路椎板减压髓核摘除术,其中小切口开窗35例,半椎板切除20例,全椎板切除7例,根据手术前后JOA评分评价手术疗效.结果 老年腰椎间盘突出症病理以髓核组织的脱水,纤维环的破裂,小关节囊、周围韧带及软骨终板退变为主要特点.临床特点为下肢疼痛多发,腰部活动受限较多;双下肢神经系统检查肌力下降明显,生理反射改变明显.62例平均随访1.9年,JOA评分术后平均改善率为68.9%,手术前后JOA评分比较差异有显著性意义(P<0.05).结论 老年腰椎间盘突出症患者病程长,体征多,病理改变明显,行腰椎后路椎板减压髓核摘除术,手术效果满意. 相似文献
82.
Obstructive sleep apnea has traditionally been viewed as a structural disease. A multitude of systemic endocrine and cardiovascular abnormalities have been previously attributed to the prevalence of obesity in these patients. A growing body of clinical evidence, however, points to a relationship between sleep apnea and its systemic abnormalities independent of obesity. We hypothesize that this association is based on a maladaptive autonomic response of chemoreceptors, reacting to the hypoxia, hypercapnia, and acidosis of sleep apnea. The elevated sympathetic response triggers an inflammatory cascade that results in a myriad of downstream consequences including insulin resistance, hypertension, diabetes, atherosclerosis and metabolic syndrome. The sympathetic bias and endocrine disturbances may further exacerbate sleep disturbance in a potentially pernicious cycle. Our proposal may extend to any chronic respiratory or metabolic conditions that manifest hypoxia, hypercapnia, and acidosis and elicit a maladaptive autonomic and inflammatory response. 相似文献
83.
Rapid leukocyte integrin activation by chemokines 总被引:12,自引:0,他引:12
Carlo Laudanna Ji Yun Kim Gabriela Constantin Eugene C. Butcher 《Immunological reviews》2002,186(1):37-46
Summary: Chemokines control selective targeting of circulating leukocytes to the microvasculature by triggering inside-out signal transduction pathways leading to integrin-dependent adhesion. Integrin activation by chemokines is very rapid, is downmodulated within minutes and appears to involve both enhanced heterodimer lateral mobility on the plasma membrane, facilitating encounters with dispersed ligand, as well as induction of a high-affinity state. These two modalities of integrin activation by chemokines involve distinct signaling pathways in the cell, yet complement each other functionally, allowing binding of rolling cells under conditions of low as well as high ligand density. Recent data show that chemokines generate both pro- and anti-adhesive intracellular signaling events, whose equilibrium is likely to be relevant to the kinetics of adhesion and de-adhesion, and to cell movement during diapedesis and chemotaxis. Importantly, chemokines utilize different signaling mechanisms to modulate the activity of distinct integrin subtypes. These recent advances suggest that chemokines may regulate adhesive responses of immune cells based not only on patterns of chemokine receptor expression, but also on variable signaling pathways that can modulate the pro-adhesive responses of leukocytes as a function of their differentiated state, and of the local microenvironment. 相似文献
84.
The kanamycin resistance determinant in P1Km lies between am33 and gene 2 on the P1 genetic map. This is within the invertible region (C loop) of P1 DNA. 相似文献
85.
Relative carriage rates of nuclear dehydrogenating clostridia in two populations of different colorectal cancer risk 下载免费PDF全文
Carriage of nuclear dehydrogenating clostridia has been associated with colon cancer and implicated in its aetiology. This study has compared the carriage of these organisms in a British population at high risk for the development of colon cancer with a low risk Nigerian population. Clostridia were found in all of the stools from both populations. Nuclear dehydrogenating clostridia were only found in the stools of the British subjects (32%). These results support the suggestion that the carriage rate of nuclear dehydrogenating clostridia in a population is related to the risk of colon cancer. 相似文献
86.
87.
目的:探讨内皮细胞清除补体攻膜复合物(MAC)的途径及其清除动力学,方法:原代培养的人脐静脉内皮细胞以RH414荧光标记质膜双层,0℃组装亚溶剂量的MAC,37℃复苏后,LSCM实时监MAC沉积诱导的质膜囊泡化形成和胞吞,胞吐情况,流式细胞仪定量检测内皮细胞表面MAC抗原的清除情况,结果:MAC沉积后,内皮细胞有的质膜囊泡化形成,囊泡以胞吞和胞吐2种方式离开细胞,并以前者占优,37度条件下,内皮细胞清除表面MAC的半衰期约为5min。结论:内皮细胞可通过胞吞和胞吐2种机制清除细胞表面沉积的MAC,并以胞吞方式为主。 相似文献
88.
One cDNA clone was purified from an adult Clonorchis sinensis cDNA library, and its deduced polypeptide sequence was found to be homologous with myosin regulatory light chain (MRLC) of invertebrates and vertebrates. Two amino-acid residues, Thr and Ser, were conserved at the phosphorylation sites that regulate the function of MRLCs. Recombinant C. sinensis MRLC (rCsMRLC) protein was produced and purified from Escherichia coli, and mouse anti-CsMRLC immune sera recognized a protein of molecular weight 24 kDa from a soluble protein preparation of C. sinensis. The CsMRLC protein was immunohistochemically localized to the muscle fibers of the subtegumental muscle layer and to the muscles of oral and ventral suckers. However, the rCsMRLC protein proved to be less useful antigen for the serodiagnosis of human clonorchiasis.The nucleotide sequence reported herein was submitted to GenBank and assigned accession number AY519356. 相似文献
89.
To optimize fitness under conditions of varying Darwinian opportunity, organisms demonstrate tremendous plasticity in their life-history strategies based on their perception of available resources. Higher-energy environments generally promote more aggressive life-history strategies, such as faster growth, larger adult size, greater genetic variation, shorter lifespan, larger brood sizes, and offspring ratio skewed towards the larger-sized gender. While numerous mechanisms regulate life-history plasticity including genetic imprinting, methylation, and growth factors, evidence suggests that thyroid hormone plays a central role. Given the pivotal adaptive role of thyroid hormone, the teleology of its dependence on dietary iodine for production remains unexplained. We hypothesize that iodine may have emerged as a substrate for production of thyroid hormone in prehistoric ecosystems because the former represented a reliable proxy for ecologic potential that enabled the latter to modulate growth, reproduction, metabolic rate, and lifespan. Such a scenario may have existed in early marine ecosystems where ocean-surface vegetation, which concentrates iodine for its antimicrobial and antioxidant properties, formed the basis of the food chain. Teleologic parallels can be drawn to the food-chain accumulation of antimicrobials that also exhibit antioxidant properties and promote adult size, brood size, and offspring quality by modulating central hormonal axes. As each higher species in the food chain tunes its life-history strategy based on iodine intake, the coupling of this functional role of iodine with its value as a resource signal to the next member of the food-chain may promote runaway evolution. Whereas predators in prehistoric ecosystems successfully tuned their life-history strategy using iodine as a major input, the strategy may prove maladaptive in modern humans for whom the pattern of iodine intake is decoupled from resource availability. Iodine acquired through sodium iodide supplementation may independently contribute to some biologic dysfunctions currently attributed to sodium. 相似文献
90.
为了探讨趋化性细胞因子在体外对人Tc1和Tc2亚群细胞内Ca2 + 浓度变化的影响 ,从PBMC中分离纯化CD8+ T细胞 ,在特定细胞因子及细胞因子抗体作用下 ,体外定向诱导出能长期培养的Tc1和Tc2细胞系 ,用免疫荧光染色结合流式细胞术分析对其进行鉴定后 ,通过流式细胞术检测在趋化性细胞因子刺激前后 ,细胞内Ca2 + 浓度的变化。发现受SDF 1作用后 ,Tc1及Tc2细胞内Ca2 + 浓度变化均不明显 ,而IP 10刺激后 ,Tc1及Tc2细胞内Ca2 + 水平在短时间内明显上调 ,且在Tc1胞内的上升幅度远高于Tc2细胞 ,在MIP 1β刺激后 ,也观察到类似趋势 ;受Eotaxin刺激后 ,Tc1及Tc2细胞内Ca2 + 水平均有微小上升 ,在Tc2细胞内的上升幅度略高于Tc1细胞。说明Tc1和Tc2细胞受趋化性细胞因子作用后 ,细胞内Ca2 + 浓度有不同程度的变化 ,且与趋化性细胞因子受体的表达呈现一定的相关性。 相似文献