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1.
目的:研究对比股骨近端防旋髓内钉(PENA-Ⅱ)与联合加压交锁髓内钉(Inter Tan)治疗老年股骨转子间骨折的疗效。方法:选择2014年6月至2016年6月我院收治的老年股骨转子间骨折患者92例,按照随机数字表法分为PENA-Ⅱ组与Inter Tan组,每组各46例。两组患者分别接受PENA-Ⅱ治疗和Inter Tan治疗,术后进行为期12个月的随访。比较两组临床疗效、手术相关指标(手术时间、术中出血量、骨折愈合时间)、手术前后骨密度水平变化情况以及并发症发生情况。结果:PENA-Ⅱ组优良率为89.13%,略高于Inter Tan组的86.96%,但两组比较差异无统计学意义(P0.05)。PENA-Ⅱ组患者手术时间、术中出血量分别为(65.2±15.3)min、(57.2±29.3)m L,明显低于Inter Tan组患者的(84.3±13.8)min、(104.7±36.5)m L(P0.05),两组患者骨折愈合时间比较差异无统计学意义(P0.05)。术前、术后12周以及术后24周PENA-Ⅱ组患者的腰椎骨密度水平与Inter Tan组比较差异无统计学意义(P0.05)。两组切口感染、肺部感染、下肢深静脉血拴、近端股骨外侧皮质劈裂以及髋内翻发生率对比差异无统计学意义(P0.05)。结论:PENA-Ⅱ与Inter Tan治疗老年股骨转子间骨折的临床疗效相当,且两种手术方法对骨密度水平的影响及术后并发症发生率相似。但PENA-Ⅱ治疗具有手术时间短以及术中出血量少等优势,值得临床推广应用。  相似文献   
2.
Drug delivery to the brain for the treatment of pathologies with a CNS component is a significant clinical challenge. P‐glycoprotein (PgP), a drug efflux pump in the endothelial cell membrane, is a major factor in preventing therapeutics from crossing the blood‐brain barrier (BBB). Identifying PgP regulatory mechanisms is key to developing agents to modulate PgP activity. Previously, we found that PgP trafficking was altered concomitant with increased PgP activity and disassembly of high molecular weight PgP‐containing complexes during acute peripheral inflammatory pain. These data suggest that PgP activity is post‐translationally regulated at the BBB. The goal of the current study was to identify proteins that co‐localize with PgP in rat brain microvessel endothelial cell membrane microdomains and use the data to suggest potential regulatory mechanisms. Using new density gradients of microvessel homogenates, we identified two unique pools (1,2) of PgP in membrane fractions. Caveolar constituents, caveolin1, cavin1, and cavin2, co‐localized with PgP in these fractions indicating the two pools contained caveolae. A chaperone (Hsc71), protein disulfide isomerase and endosomal/lysosomal sorting proteins (Rab5, Rab11a) also co‐fractionated with PgP in the gradients. These data suggest signaling pathways with a potential role in post‐translational regulation of PgP activity at the BBB.

  相似文献   

3.
Interleukin-33 is a newly described member of the interleukin-1 family. Recent research suggests that IL-33 is increased in lungs and plays a critical role in chronic airway inflammation in cigarette smoke-induced chronic obstructive pulmonary disease (COPD) mice. To determine the role of IL-33 in systemic inflammation, we induced COPD mice models by passive cigarette smoking and identified the IL-33 expression in bronchial endothelial cells and peripheral blood mononuclear cells (PBMCs) of them. After isolation, PBMCs were cultured and stimulated in vitro. We measured expressions of interleukin-6 and interleukin-8 in PBMCs in different groups. The expression of IL-33 in bronchial endothelial cells and PBMCs of COPD mice were highly expressed. Stimulated by cigarette smoke extract (CSE), the expression of IL-6 and IL-8 were induced and enhanced by IL-33. PBMCs of COPD mice produced more IL-6 and IL-8 stimulated by CSE and IL-33. Expression of IL-6 and IL-8 were decreased when stimulated by IL-33 together with soluble ST2. The mRNA production of ST2 in IL-33 stimulated PBMCs was increased. Being pretreated with several kinds of MAPK inhibitors, the secretions of IL-6 and IL-8 in PBMCs did not decrease except for the p38 MAPK inhibitor. We found that IL-33 could induce and enhance the expression of IL-6 and IL-8 in PBMCs of COPD mice via p38 MAPK pathway, and it is a promoter of the IL-6 and IL-8 production in systemic inflammation in COPD mice.  相似文献   
4.
Peripheral blood mononuclear cell (PBMNC) is one of powerful tools for therapeutic angiogenesis in hindlimb ischemia. However, traditional approaches with transplanted PBMNCs show poor therapeutic effects in severe ischemia patients. In this study, we used autograft models to determine whether hypoxic pretreatment effectively enhances the cellular functions of PBMNCs and improves hindlimb ischemia. Rabbit PBMNCs were cultured in the hypoxic condition. After pretreatment, cell adhesion, stress resistance, and expression of angiogenic factor were evaluated in vitro. To examine in vivo effects, we autografted preconditioned PBMNCs into a rabbit hindlimb ischemia model on postoperative day (POD) 7. Preconditioned PBMNCs displayed significantly enhanced functional capacities in resistance to oxidative stress, cell viability, and production of vascular endothelial growth factor. In addition, autologous transplantation of preconditioned PBMNCs significantly induced new vessels and improved limb blood flow. Importantly, preconditioned PBMNCs can accelerate vessel formation despite transplantation on POD 7, whereas untreated PBMNCs showed poor vascularization. Our study demonstrated that hypoxic preconditioning of PBMNCs is a feasible approach for increasing the retention of transplanted cells and enhancing therapeutic angiogenesis in ischemic tissue.  相似文献   
5.
目的:探讨淋巴结转移阴性胃癌患者的临床病理特征以及预后影响因素。方法:收集2000年1月至2009年1月我院收治的胃癌患者325例,其中经病理检查显示淋巴结转移阴性的105例患者作为阴性组(LN-组),另229例阳性患者作为阳性组(LN+组),比较两组的临床病理特征及临床预后。结果:LN-组的肿瘤直径、浸润深度及术后化疗与LN+组比较差异显著(P0.05);LN-组的5年生存率为76.2%,显著高于LN+组的43.2%(P0.05)。未透浆膜的LN-患者3年、5年生存率显著高于浸透浆膜者,术后化疗的LN-患者5年生存率显著高于未化疗者(P0.05),肿瘤直径5 cm的LN-患者3、5年生存率显著高于≥5 cm者(P0.05)。单因素分析显示浸润深度、肿瘤大小及术后化疗与LN-胃癌患者的预后具有密切关系(P0.05)。COX多因素分析显示浸润深度是影响LN-胃癌患者临床预后的独立因素(P0.05)。结论:淋巴结转移阴性胃癌患者的病灶多位于中下部,男性多于女性,发病年龄多在60岁以内,肿瘤直径多不超过5 cm,浸润深度多未浸透浆膜,临床预后优于淋巴结转移阳性胃癌患者,浸润深度是影响淋巴结转移阴性胃癌患者临床预后的独立因素。  相似文献   
6.
7.
在高中生物教学中,血糖平衡的调节一直是重要的教学内容。以往的教学设计思路主要是依靠教师讲述,学生被动接受,因此学生在学习上缺乏主动性。且由于内容比较抽象,学生很难真正理解。教师如何依据现代教育理论,通过组织和引导学生模拟血糖的调节机制,建构和不断修正动态的物理模型,再建构抽象的血糖调节的图解式概念模型,从而使学生深入理解血糖调节的机制,更好地理解体内激素对生命活动进行的调节,不仅是突破教学难点有效途径,对学生建立科学思维方式也具有重要的意义。结合课堂教学实际,介绍“建立血糖调节模型”的教学设计和“概念模型”的教学组织策略两个方面研究成果。  相似文献   
8.
Brain energy disorders and oxidative stress due to chronic hypoperfusion were considered to be the major risk factors in the pathogenesis of dementia. In previous studies, we have demonstrated that acupuncture treatment improved cognitive function of VaD patients and multi-infarct dementia (MID) rats. Acupuncture therapy also increased the activities of glycometabolic enzymes in the brain. But it is not clear whether acupuncture treatment compensates neuronal energy deficit after cerebral ischemic through enhancing the activities of glucose metabolic enzymes and preserving mitochondrial function, and whether acupuncture neuroprotective effect is associated with activations of mitochondrial antioxidative defense system. So, the effect of acupuncture therapy on cognitive function, cerebral blood flow (CBF), mitochondrial respiratory function and oxidative stress in the brain of MID rats was investigated in this study. The results showed that acupuncture treatment significantly improved cognitive abilities and increased regional CBF of MID rats. Acupuncture elevated the activities of total SOD, CuZnSOD and MnSOD, decreased the level of malondialdehyde (MDA) and superoxide anion, regulated the ratio of reduced glutathione (GSH) and oxidized glutathione (GSSG) in mitochondria, and raised the level of the respiratory control index (RCI) and P/O ratio and the activities of mitochondrial respiratory enzymes of MID rats. These results indicated that acupuncture treatment improved cognitive function of MID rats; and this improvement might be due to increased CBF, which ameliorated mitochondrial dysfunction induced by ischemia and endogenous oxidative stress system of brain.  相似文献   
9.
Sphingosine-1-phosphate (S1P) is a bioactive sphingolipid that acts either as an intracellular messenger or as a ligand for its membrane receptors. S1P is a normal constituent of blood, where it is found both in plasma and blood cells. Compared with other cell types, sphingolipid metabolism in erythrocytes and platelets has unique features that allow the erythrocytes and platelets to accumulate S1P. In plasma, S1P is bound mainly to HDLs and albumin. Of note, metabolism and biological activity of S1P is to a large extent affected by the type of its carrier. Plasma S1P is characterized by a short half-life, indicating rapid clearance by degradative enzymes and the presence of high-capacity sources involved in maintaining its high concentration. These sources include blood cells, vascular endothelium, and hepatocytes. However, the extent to which each of these contributes to the plasma pool of S1P is a matter of debate. Circulating S1P plays a significant physiological role. It was found to be the key regulator of lymphocyte trafficking, endothelial barrier function, and vascular tone. The purpose of this review is to summarize the present state of knowledge on the metabolism, transport, and origin of plasma S1P, and to discuss the mechanisms regulating its homeostasis in blood.  相似文献   
10.
High‐throughput sequencing is revealing that most macro‐organisms house diverse microbial communities. Of particular interest are disease vectors whose microbiome could potentially affect pathogen transmission and vector competence. We investigated bacterial community composition and diversity of the ticks Dermacentor variabilis (n = 68) and Ixodes scapularis (n = 15) and blood of their shared rodent host, Peromyscus leucopus (n = 45) to quantify bacterial diversity and concordance. The 16S rRNA gene was amplified from genomic DNA from field‐collected tick and rodent blood samples, and 454 pyrosequencing was used to elucidate their bacterial communities. After quality control, over 300 000 sequences were obtained and classified into 118 operational taxonomic units (OTUs, clustered at 97% similarity). Analysis of rarefied communities revealed that the most abundant OTUs were tick species‐specific endosymbionts, Francisella and Rickettsia, and the commonly flea‐associated bacterium Bartonella in rodent blood. An Arsenophonus and additional Francisella endosymbiont were also present in D. variabilis samples. Rickettsia was found in both tick species but not in rodent blood, suggesting that it is not transmitted during feeding. Bartonella was present in larvae and nymphs of both tick species, even those scored as unengorged. Relatively, few OTUs (e.g. Bartonella, Lactobacillus) were found in all sample types. Overall, bacterial communities from each sample type were significantly different and highly structured, independent of their dominant OTUs. Our results point to complex microbial assemblages inhabiting ticks and host blood including infectious agents, tick‐specific endosymbionts and environmental bacteria that could potentially affect arthropod‐vectored disease dynamics.  相似文献   
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