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101.
胆道支撑管显影材料的制备及体外细胞毒性评价 总被引:4,自引:0,他引:4
目的 探讨新型显影胆道支撑管材料制备的可行性,对构建出的材料进行体外细胞毒性评价和筛选。方法 选择具有X线下显影特性的基础材料A、B、C,分别与硅橡胶生胶共混炼,模压后分别得到相应的显影复合材料甲、乙、丙,经一段和二段硫化过程完成加工。采用MTT法作为体外细胞毒性评价的方法,测定参比对照材料和新材料的50%浓度的浸提液对小鼠成纤维细胞的增殖率的影响,确定细胞毒性级别。结果 新材料甲、乙、丙在x线下影像清晰。甲、乙材料的细胞毒性级别为零,丙材料细胞毒性级别为2。结论 构建出在X线下显影的弹性体材料可行。材料甲、乙是制造新型胆道支撑管的初选材料,材料丙无应用的价值。 相似文献
102.
Controlled release of sugar and toxicant from a novel device for controlling pest insects 总被引:1,自引:0,他引:1
Xing Ping Hu Baruch S. Shasha Michael R. McGuire Ronald J. Prokopy 《Journal of controlled release》1998,50(1-3):257-265
A novel biodegradable device, designed for long-lasting residual effectiveness of feeding stimulant (sugar) and insecticide (dimethoate) against apple maggot flies and other insects, was formulated. The device is an 8-cm diameter fruit-mimicking sphere, consisting of 42–50% sugar entrapped in a mixture of gelatinized corn flour and wheat flour in the presence of glycerin, and coated with a layer of latex paint containing dimethoate and sugar. We found that the outer layer of paint prevents cracking of the sphere upon drying and creates a barrier to control the release of both sugar and dimethoate. Releases of each ingredient were screened first by chemical analysis and then by bioassays in the laboratory and in field cages against apple maggot flies. Chemical analysis demonstrated strong potential for controlled release of water-soluble feeding stimulant and water-insoluble insecticide measured as a function of the amount of rainfall and duration of exposure time. Field results showed greater than 70% insecticidal activity after 11 weeks of sphere exposure in an orchard. This device has the potential to be used for a variety of insect-control applications through manipulating its shape, color and texture into forms known to be attractive to target insects, and by employing various toxicants designed to be effective against such insects. 相似文献
103.
侧唇唇缘红唇肌瓣再造双侧唇裂患者唇珠及唇缘 总被引:4,自引:4,他引:0
目的:利用侧唇重要的解剖学指标,再造双侧唇裂人中部唇缘及唇珠,探求一种有效的功能性修复双侧唇裂唇缘及唇珠的方法。方法:2000年~2005年本院收治的唇裂患者中,双侧唇裂患者76例,男性54例,女性22例。年龄最大19岁,最小4/12岁。通过设计侧唇唇缘红唇肌瓣,旋转于前唇下方重建唇弓缘,该瓣末端红唇粘膜肌瓣再造唇珠的方法修复。结果:术后患者无1例裂开,无明显的口哨畸形,口轮匝肌连续完整,唇弓缘连续,唇弓自然生动,形态好。红唇丰满,红线连续,唇珠突翘明显。结论:唇缘红唇肌瓣可以较好地修复双侧唇裂下部重要解剖结构,唇缘红唇肌瓣的设计切取是手术成功的关键。 相似文献
104.
慢性阻塞性肺疾病(COPD)是一种常见的慢性呼吸系统疾病,对人类健康造成极大威胁。研究发现,COPD患者与健康人群相比,肺部菌群及肠道菌群的组成结构发生了显著改变,导致黏膜屏障功能及机体免疫稳态被破坏,进而加重病情。积极调节肺部、肠道菌群平衡对于干预COPD的发生、发展有着至关重要的作用,但目前关于肺部、肠道菌群及其相互作用机制在COPD中作用的总结和认识还有待进一步阐明。本文就健康人群以及COPD患者肺部、肠道菌群的组成特点及可能的相互作用机制,以及现阶段基于肺部、肠道菌群及其相互作用防治COPD的最新研究成果进行综述,以期为COPD的发病机制、早期诊断、预防与治疗研究提供新思路。 相似文献
105.
目的 探讨调和阴阳法针灸对老年不寐患者睡眠质量及褪黑素(MT)、去甲肾上腺素(NE)、5-羟色胺(5-HT)水平的影响。方法 选取2020年7月—2022年7月河北医科大学第一医院收治的老年不寐患者120例,采用随机数表法分为观察组和对照组,每组60例。对照组采取常规药物治疗,观察组在对照组基础上联合调和阴阳法针灸。比较两组临床疗效,同时评估其中医证候积分和匹兹堡睡眠质量指数(PSQI)评分,测定MT、NE、5-HT、多巴胺(DA)、γ-氨基丁酸(GABA)水平,观察记录不良反应发生情况。结果 观察组总有效率高于对照组(P <0.05);观察组治疗前后入睡困难、多梦易醒、神疲食少、目赤口苦、舌红少津、脉弦数、舌苔黄评分的差值均高于对照组(P <0.05)。观察组与对照组治疗前及治疗后2、4周的PSQI评分比较,结果 ①不同时间点PSQI评分比较,差异有统计学意义(F =17.894,P =0.000);②两组PSQI评分比较,差异有统计学意义(F =26.894,P =0.000),观察组PSQI评分较低,相对睡眠质量较好;③观察组与对照组PSQI评分变化趋势比较,差异有统计学意义(F =45.247,P =0.000)。观察组治疗前后睡眠总时间、快速眼动睡眠期、睡眠潜伏期、醒觉时间、睡眠效率的差值均高于对照组(P <0.05);观察组治疗前后MT、NE、5-HT的差值均高于对照组(P <0.05);观察组治疗前后DA、GABA的差值均高于对照组(P <0.05);两组不良反应总发生率比较,差异无统计学意义(P >0.05)。结论 调和阴阳法针灸治疗老年失眠症疗效显著,不仅能有效改善患者中医症状、睡眠质量及睡眠结构,还能改善血清MT、NE、5-HT、DA、GABA水平,安全性较高。 相似文献
106.
Primary sensory neurons can generate irregular burst firings in which the existence of significant deterministic behaviors of chaotic dynamics has been proved with nonlinear time series analysis. But how well the deterministic characteristics and neural information of presynaptic chaotic spike trains were transmitted into postsynaptic spike trains is still an open question. Here we investigated the synaptic transmission of chaotic spike trains between primary Adelta afferent fiber and spinal dorsal horn neuron. Two kinds of basic stimulus unit, brief burst and single pulse, were employed by us to comprise chaotic stimulus trains. For time series analysis, we defined "events" as the longest sequences of spikes with all interspike intervals less than or equal to a certain threshold and extracted the interevent intervals (IEIs) from spike trains. Return map analysis of the IEI series showed that the main temporal structure of chaotic input trains could be detected in postsynaptic output trains, especially under brief-burst stimulation. Using correlation dimension and nonlinear prediction methods, we found that synaptic transmission could influence the nonlinear characteristics of chaotic trains, such as fractal dimension and short-term predictability, with greater influence made under single-pulse stimulation. By calculating the mutual information between input and output trains, we found the information carried by presynaptic spike trains could not be completely transmitted at primary afferent synapses, and that brief bursts could more reliably transmit the information carried by chaotic input trains across synapses. These results indicate that although unreliability exists during synaptic transmission, the main deterministic characteristics of chaotic burst trains can be transmitted across primary afferent synapses. Moreover, brief bursts that come from the periphery can more reliably transmit neural information between primary afferent fibers and spinal dorsal horn neurons. 相似文献
107.
108.
目的:介绍一种大鼠活体重复采血方法。方法:大鼠腹腔麻醉后,仰卧位沿剑突下斜行向上刺入2.5~3.0cm入心,抽血。60只大鼠,每间隔10天采血2.0ml,共4次。测定其Hb、RBC、WBC、Hct、ALT、AST、TP、BUN等指标,同时心脏切片行病理学检查。结果:采用本法进行大鼠心脏取血,成功率97.8%。各次标本的实验室指标均无显著性差异(P>0.05)。20只大鼠第4次采血后剖胸,未见胸腔脏器出血、粘连、血肿等并发症。心脏切片未见心肌组织学损伤。结论:该技术操作简便,定位准确,可重复采血,动物存活率高。尤其用于自身对照,可减少动物用量,提高实验准确性。 相似文献
109.
110.
Role of Eotaxin-1 (CCL11) and CC chemokine receptor 3 (CCR3) in bleomycin-induced lung injury and fibrosis
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Huaux F Gharaee-Kermani M Liu T Morel V McGarry B Ullenbruch M Kunkel SL Wang J Xing Z Phan SH 《The American journal of pathology》2005,167(6):1485-1496
Eotaxin-1/CCL11 and its receptor CCR3 are involved in recruitment of eosinophils to diverse tissues, but their role in eosinophil recruitment in pulmonary fibrosis is unclear. The present study examined the pulmonary expression of CCL11 and CCR3 during bleomycin (blm)-induced lung injury and determined their importance in the recruitment of inflammatory cells and the development of lung fibrosis. In mice, blm induced a marked pulmonary expression of CCL11 and CCR3. Immunostaining for CCR3 revealed that this receptor was not only expressed by eosinophils but also by neutrophils. CCL11-deficient (CCL11(-/-)) mice developed significantly reduced pulmonary fibrosis. Expression of profibrotic cytokines such as transforming growth factor-beta1 was diminished in the absence of CCL11. Furthermore, increased lung expression of CCL11 significantly enhanced blm-induced lung fibrosis and production of profibrotic cytokines. These effects were also associated with an increase of eosinophil and neutrophil pulmonary infiltration. In contrast, mice treated with neutralizing CCR3 antibodies developed significantly reduced pulmonary fibrosis, eosinophilia, neutrophilia, and expression of profibrotic cytokines. Together, these data suggest that CCL11 and CCR3 are important in the pulmonary recruitment of granulocytes and play significant pathogenic roles in blm-induced lung fibrosis. 相似文献