制冷系统不平衡故障状态分析及系统调节

根据空调设备实际维护经验及参考有关文献,定性分析蒸气压缩式制冷系统从正常的工作状态到不正常状态产生的原因和理论依据,为空调设备维护中遇到的一些障碍提供一些借鉴.     

磷酸钙/BMP复合生物活性骨水泥水化性能及诱导成骨特性研究

采用微细α-磷酸三钙(α-TCP)粉料、辅助料与冻干牛骨形态发生蛋白(BMP)预先固相混合制备了新型磷酸钙(CPC)/BMP复合生物骨水泥.通过水化、凝固性能研究优化了配料成分、调和液和促凝剂组成;通过大鼠肌袋种植实验研究了骨水泥的异位成骨性能.结果表明:以α-TCP:CaHPO₄:CaO(0.95:0.025:0.025)为固相配料,以0.25mol/LNaH₂PO₄/Na₂HPO₄混合液([P]_T=0.5mol/L)作为调合液可制备性能优异的骨水泥材料,骨水泥初凝时间为6min,终凝时间为30min,固化强度达33MPa,达到临床手术的要求;α-TCP粉料粒度对骨水泥凝固性能影响显著,实验选用α-TCP粉料粒径d₅₀为1.3μm;骨水泥在Hank’s溶液中浸泡5天抗压强度可达最大值;骨水泥块经浸泡后内部生成针状羟基磷灰石晶体的网状结构.新型CPC/BMP复合骨水泥异位成骨作用明显,4周即能快速形成板层骨结构,证明该新型复合材料具有较强的诱导成骨活性.该生物活性骨水泥复合材料可望成为一类新型组织工程骨修复材料.     

Modification of chitosan by zeolite A and adsorption of Bezactive Orange 16 from aqueous solution

This study represents new material based on chitosan modified by zeolite A as adsorbent for anionic dye, using Bezactive Orange 16 as a model compound. Interactions between dye and chitosan/zeolite A film at initial concentrations and pH dye solution was investigated. In order to determine kinetics and the mechanism of adsorption four kinetic models were used. The results showed that the adsorption of Bezactive Orange 16 dye onto chitosan/zeolite A can be best described by pseudo-second order model. According to the Langmuir model, the maximum adsorption capacity reached 305.8 mg/g. The films could be potentially used as absorbents for anionic dye removal in wastewater treatment process.     

三维影像在颅内动脉瘤栓塞中的应用

目的评价３D-CTA，MRA和３D-DSA在动脉瘤致密填塞中的应用价值。方法６４例颅内动脉瘤患者（检出７２枚动脉瘤），血管内栓塞治疗６０枚。研究并比较CTA，MRA和DSA影像特点。结果６０枚栓塞的动脉瘤中５０枚致密填塞，１０枚为大于９５％填塞，５枚为大于９０％填塞。３D-CTA对动脉瘤测量值比２D-DSA大，３D-DSA比２D-DSA大。结论动脉瘤应用血管内栓塞治疗时，在３D影像指导下可提高动脉瘤的致密填塞率。但是３D影像的测量值要大于２D影像的测量值。     

环丙沙星对美吡达的药代学和药效学的影响

目的 研究美吡达与环丙沙星联合应用时环丙沙星对美吡达药代动力学及药效学的影响。方法 糖尿病大鼠24 只分为联合用药组(环丙沙星+美吡达)及单独用药组(美吡达),治疗9 d 后分别测定两组美吡达血药浓度并计算药代动力学参数及血糖。结果 两组大鼠美吡达的药代动力学过程均符合一房室模型。且联合用药组美吡达血药浓度显著升高,清除率下降50%(P<0.05),吸收半衰期延长63.7 %(P<0.05),单独应用美吡达治疗后血糖为5.978 mmol·L^-1,联合应用环丙沙星治疗后血糖为5.301 mmol·L^-1;两组降糖效果差异具有显著性。结论 环丙沙星对美吡达的吸收药代动力学有影响,美吡达联合应用环丙沙星降糖效果比单独应用美吡达时强。故同时给药时应注意调整美吡达的用药剂量以保证用药安全。     

Osteogenesis Capacity of a Novel BMP/α-TCP Bioactive Composite Bone Cement

1　IntroductionHumanboneisacompositematerialmadeupofcol lagenandcalciumphosphateminerals .Inlasttwode cades ,remarkableadvanceshaveledtotherapiddevelop mentofvariousbiomaterialsforbonerepairandprosthesesapplication ,especiallythebonetissueengineeringmater…     

基于外侧腓肠肌sEMG的帕金森神经调控步态量化测评方法

帕金森(Parkinson's disease,PD)患者脑深部电刺激(deep brain stimulation,DBS)神经调控治疗迫切需要客观、量化的测评手段和分析方法.针对这一临床需求,本文提出一种基于外侧腓肠肌(lateral gastrocnemius,LG)表面肌电(surface electromyo...     

重组人血管内皮抑制素注射液联合冷冻消融治疗肺腺癌A549移植瘤的实验研究

【摘要】 目的 探讨重组人血管内皮抑素注射液（商品名:恩度）联合冷冻消融对肺腺癌A549移植瘤的抑制作用及机制。方法 建立肺腺癌A549裸鼠皮下移植瘤模型24只,待肿瘤最大直径达1 cm时,随机分为对照组、血管内皮抑素组、冷冻消融组和血管内皮抑素联合冷冻消融组（联合治疗组）。治疗后第21天处死裸鼠,取肿瘤组织,测量肿瘤体积,采用末端标记法（TUNEL）原位检测周边冷冻损伤区带细胞凋亡,免疫组化SP法检测肿瘤组织微血管密度（MVD）、血管内皮生长因子（VEGF）表达水平。结果 治疗后第21天,对照组、血管内皮抑素组、冷冻消融组和联合治疗组的肿瘤生长速率分别为236.68% ± 51.23%、220.02% ± 30.61%、159.46% ± 29.33%和103.34% ± 25.50%,组间差异有统计学意义（P ＜ 0.01）;肿瘤细胞凋亡率分别为21.67% ± 2.34%、22.17% ± 1.47%、38.33% ± 1.37%和49.17% ± 1.72%,组间差异有统计学意义（P ＜ 0.01）。联合治疗组的MVD、VEGF表达水平均明显低于其他各组（P ＜ 0.01）。MVD与VEGF之间呈正相关关系（r = 0.925,P < 0.01）。结论 血管内皮抑素可明显提高冷冻消融对肺腺癌A549移植瘤的抑制效果,其机制可能与血管内皮抑素通过下调VEGF 表达水平,从而抑制肿瘤新生血管形成,协同冷冻消融促进肿瘤细胞凋亡有关。     

基底动脉中段支架术后穿支动脉闭塞的相关研究

摘要】 目的 探讨基底动脉中段支架术后穿支动脉闭塞的影响因素,提供改善临床疗效的方法。方法 回顾性分析26例应用Wingspan支架治疗症状性颅内基底动脉中段狭窄的疗效,观察其技术成功率、狭窄率的改变、围手术期并发症及术后症状改善情况。结果 26例患者共植入27枚Wingspan支架,技术成功率为100%。术后即刻血管造影证实,狭窄率由（78.8 ± 7.5）%降为（23.1 ± 7.4）%。2例患者出现围手术期并发症。按照Malek评分,分别评价术后24 h,术后1个月的预后情况:术后24 h评分,1分25例,4分1例;1个月后评分1分24例,4分1例,5分1例（术后2周死于肺部感染）;随访术后6 ~ 21个月,1分22例,3分1例,5分2例（1例患者术后7个月死于脑出血）,失访1例。结论 应用Wingspan支架治疗症状性基底动脉中段狭窄对于穿支动脉的闭塞可以通过积极的措施预防及治疗,初步结果显示效果良好,但仍须大样本随机对照研究进行验证。
     

Osteogenesis Capacity of a Novel BMP／a-TCP Bioactive Composite Bone Cement

To improve the osteogenesis ability of α-trkalcium phosphate (a-TCP ) bone cement, a novel BMP/ a- TCP composite bone cement was prepared. By measuring the setting time and compressive strength, the hydration characteristic of bone cemtwnt icts eralnated. Animal experiments including histological observation, radiographic investigation as well as digital image analyses reveal the difference of osteogenesis ability among BMP, a TCP bone cetnent and BMPI a-TCP composite bone cement, Results show that a-TCP bone cement possesses excellent hydration and setting properties as well as high mechanical property, Comparison experiments show that BMPI a-TCP composite bonc cement has a stronger osteogenesis obility. The gross observation of the implant site does not exhibit any inflammation or necrosis. Histohwcal analyses reveal that the material has good osteointegration with host bone, and new bone formntion is detected within the materials, which are degrading. Strong osteogenesis ability of the composite is due to not only the excellent osteoconductive potential but also the osteoinductive potential contributed by attire BMP releasing and the material degradation . Large skull defect could be well-healed ty filling BMPl a-TCP composite bone cement. This novel material proves itself to be an absorbable and bioaetive bonecement with an osteogenesi ability.