壮龄剂抗老化作用的实验研究

用壮龄剂对大白鼠进行抗老化研究。结果表明,壮龄剂可降低大鼠肝、肾及心肌等组织中的过氧化脂质(LPO);提高血清超氧化物岐化酶(SOD)的活性;对血清总胆固醇(TC)和低密度脂蛋白(LDL)有显著降低作用;对高密度脂蛋白胆固醇(HDL—C)有升高作用。该药能抑制肾上腺皮质、脊神经节等细胞中脂褐素的形成以及肝、肾上腺皮质、脑垂体远侧部细胞内线粒体超微结构的老龄变化。     

肾上腺素联合艾司洛尔对心室颤动复苏模型家兔肺水肿的影响

目的:探讨肾上腺素联合艾司洛尔对心室颤动复苏家兔复苏早期肺水肿及心脏标志物的影响。方法:将26只清洁级家兔随机分为3组,其中20只清洁级家兔采用交流电致心室颤动建立心肺复苏模型,另6只为手术对照组(A组),仅行麻醉、手术、气管插管,不制作心肺复苏模型。模型家兔随机均分10只,分别在复苏时给予肾上腺素10μg/kg(B组)和在复苏时给予肾上腺素10μg/kg+艾司洛尔200μg/kg(C组)。测量复苏成功后5 h肺湿/干比重,比较复苏后30 min、1 h、2 h、4 h时血清肌钙蛋白(cTnI)水平及丙二醛(MDA)活性的变化。结果:A、C、B组家兔于模型复苏成功后5 h肺湿/干比重、cTnI水平和MDA活性依次升高,差异均有统计学意义(P0.01～P0.05)。结论:艾司洛尔可以减轻家兔心室颤动复苏后肺水肿,对复苏后早期心脏有保护作用。     

后路椎间融合器结合新型椎弓根钉系统治疗腰椎滑脱症

目的 探讨纯钛多孔涂层后路椎间融合器结合新型椎弓根钉系统对腰椎滑脱症的治疗效果。方法 33例腰椎滑脱症病人,采用后路全椎板切除减压、纯钛多孔涂层后路椎间融合器行椎间融合、新型椎弓根钉系统内固定治疗。结果 33例术后均随访,时间6~36个月,平均18.6个月。本组患者术后无神经损伤和切口感染,动态摄片观察无融合器移位、椎弓根螺钉松脱、断裂等并发症。按Brantigan评价标准评定结果:优21例、良10例、可2例、差0例。结论 纯钛多孔涂层后路椎间融合器结合新型椎弓根钉系统治疗腰椎滑脱症,具有椎管减压充分、椎体复位好、术后能立即改善疼痛症状、立即稳定椎体、病人可早期下床等优点,是一种治疗腰椎滑脱症较理想的方法。     

结肠在平卧位经皮肾穿刺造瘘中损伤的影像解剖学研究

目的探讨平卧位经皮肾穿刺结肠损伤的机制和几率,为临床经皮肾镜手术提供理论指导。方法对412例平卧位腹部CT进行回顾性分析,模拟一条自腰椎前切缘分别经过肾上极、肾门、肾下极的穿刺线,将升、降结肠位置分为穿刺线前、线后或线上,前者定义为无潜在损伤风险,后两者定义为有潜在损伤风险,从影像学、解剖学上分析平卧位经皮肾穿刺结肠损伤的机制和概率。结果经左侧肾上极、肾门、肾下极的穿刺中结肠有潜在损伤风险的分别为0例、0例、3例（0.73%）;右侧肾上极、肾门、肾下极的穿刺中无1例有潜在损伤风险。结论平卧位行经皮肾穿刺结肠损伤发生机率低,但经皮肾镜术前最好常规行CT检查了解解剖变异,以避免结肠损伤严重并发症的发生。     

亚低温对急性肺损伤肺保护作用的临床研究

目的探讨亚低温对急性肺损伤(ALI)肺保护作用及机制。方法 97例ALI随机分为亚低温组和对照组,呼吸末气道闭合法评估肺顺应性变化,监测机体氧和,测定肺局部IL-6及血浆降钙素原(PCT),统计机械通气时间及参数变化。结果与对照组相比,亚低温组机械通气时间缩短,呼吸机支持力度下降,肺局部IL-6及PCT下降,肺顺应性、动脉血氧分压提高,肺泡-动脉氧分压差下降,肺功能改善,差异有统计学意义(P<0.05)。结论亚低温可保护ALI患者肺功能,与强化抗炎、改善氧和等有关。     

围术期离床锻炼联合呼吸训练对股骨颈骨折老年患者肺功能和PSQI评分的意义

股骨颈骨折是发生在股骨头至股骨颈基底部之间的一种骨折类型,主要表现为下肢活动受限,髋部疼痛,无法站立、行走[1?2].股骨颈骨折多与老年人骨质量下降有关,在轻微扭转引发的间接暴力作用下发生[3].临床上治疗股骨颈骨折的主要方法是进行外科手术,老年患者多存在自身疾病,加之衰老引起的器官生理构造改变、生理功能衰退等原因,老...     

Human influenza A (H5N1) cases, urban areas of People's Republic of China, 2005-2006

We investigated potential sources of infection for 6 confirmed influenza A (H5N1) patients who resided in urban areas of People's Republic of China. None had known exposure to sick poultry or poultry that died from illness, but all had visited wet poultry markets before illness.     

Unraveling the Phase Stability and Physical Property of Modulated Martensite in Ni2Mn1.5In0.5 Alloys by First-Principles Calculations

Large magnetic field-induced strains can be achieved in modulated martensite for Ni-Mn-In alloys; however, the metastability of the modulated martensite imposes serious constraints on the ability of these alloys to serve as promising sensor and actuator materials. The phase stability, magnetic properties, and electronic structure of the modulated martensite in the Ni₂Mn_1.5In_0.5 alloy are systematically investigated. Results show that the 6M and 5M martensites are metastable and will eventually transform to the NM martensite with the lowest total energy in the Ni₂Mn_1.5In_0.5 alloy. The physical properties of the incommensurate 7M modulated martensite (7M–IC) and nanotwinned 7M martensite (7M−(52¯)2) are also calculated. The austenite (A) and 7M−(52¯)2 phases are ferromagnetic (FM), whereas the 5M, 6M, and NM martensites are ferrimagnetic (FIM), and the FM coexists with the FIM state in the 7M–IC martensite. The calculated electronic structure demonstrates that the splitting of Jahn–Teller effect and the strong Ni–Mn bonding interaction lead to the enhancement of structural stability.     

Restirring and Reheating Effects on Microstructural Evolution of Al–Zn–Mg–Cu Alloy during Underwater Friction Stir Additive Manufacturing

Friction stir additive manufacturing (FSAM) can be potentially used for fabricating high-performance components owing to its advantages of solid-state processing. However, the inhomogeneous microstructures and mechanical properties of the build attributed to the complex process involving restirring and reheating deserve attention. This study is based on the previous research of the underwater FSAMed 7A04 aluminum alloy and adopts a quasi in situ experimental method, i.e., after each pass of the underwater FSAM, samples were taken from the build for microstructural observation to investigate the restirring and reheating effects on microstructural evolution during the underwater FSAM. Fine-grain microstructures were formed in the stir zone during the single-pass underwater FSAM. After restirring, the grain size at the bottom of the overlapping region decreased from 1.97 to 0.87 μm, the recrystallization degree reduced from 74.0% to 29.8%, and the initial random texture transformed into a strong shear texture composed of the C {110}<11¯0>. After reheating, static recrystallization occurred in the regions close to the new additive zones, increasing the grain size and recrystallization degree. This study not only revealed the microstructural evolution during the underwater FSAM but also provided a guideline for further optimization of the mechanical properties of the Al–Zn–Mg–Cu alloy build.     

探讨ICU获得性肺部感染的病因分析

目的探讨ICU院内获得性肺部感染的病因。方法183例危重病患者均来自于2004年1月~2006年4月入住怀化医学高等专科学校附属医院暨怀化市第三人民医院ICU的患者。结果183例危重病患者中发生院内获得性肺部感染47例,感染率25.68%。年龄愈大、住院时间愈长、采用手术治疗、气管插管或切开的患者,肺部感染率愈高。结论ICU院内获得性肺部感染率较高,应引起临床医务人员的高度重视。