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81.
实验以膈肌肌电图(EMGdi)及膈肌诱发电位为指标,观察辅助酶Q10对兔膈肌作用,发现:(1)复制膈肌疲劳(DIF)后静脉注射CoQ10mg/kg,对DIF有治疗作用,(2)提前1静脉注射CoQ1010mg/kg预处理,对电致作膈肌有保护作用。  相似文献   
82.
目的探讨距骨颈骨折治疗方案的选择以及疗效相关因素分析。方法距骨颈骨折15例,男13例,女2例。年龄16~63岁,平均40.5岁,合并腰椎、髋臼、跟骨、外踝骨折各1例。开放骨折2例。陈旧性骨折2例(〉1个月)。按Hawkins骨折分类:Ⅰ型3例、Ⅱ型9例、Ⅲ型3例。Ⅰ型骨折采用膝下管型石膏固定,其中1例复诊中因移位行切开复位松质骨螺钉固定。Ⅱ型骨折均行切开复位,克氏针或松质骨螺钉固定。Ⅲ型骨折1例开放性骨折,急诊行清创缝合,手法+撬拔复位,脱位整复。一周后在C臂机引导下,采用二枚直径4.0mm中空螺钉由后向前固定距骨颈,1例急诊手术切开复位,克氏针内固定。结果本组13例获得随访,时间4~24个月,平均12.3个月。13例中发生距骨体缺血性坏死5例,其中Ⅱ型骨折4例,Ⅲ型骨折1例。另2例未统计在内。1例外院病例术后并发伤口感染长期不愈,行小腿截肢术。1例患者拒绝手术治疗。按Hawkims疗效标准,优4例,良4例,可3例,差2例,优良率69%。结论对无移位的距骨颈骨折,行膝下管型石膏固定6~12周,并定期拍片复查,距骨颈骨折脱位应急诊复位和可靠的内固定。以2枚拉力螺钉内固定为宜,尽量减少并发症。对距骨体缺血性坏死,或创伤性关节炎,则根据患者的实际情况采取相应治疗措施。  相似文献   
83.
To investigate whether obesity is associated with alterations in respiratory chemosensitivity, we compared the ventilatory response to hypoxia (HVR) and hypercapnia (HCVR) in 9 obese men (BMI: 37.0+/-4.3 kg m(-2)) and 10 lean men (BMI: 25.8+/-4.8 kg m(-2)). HVR (DeltaVE, L min(-1) per DeltaSaO2, %) was measured by a progressive isocapnic hypoxia technique, and HCVR (DeltaVE/DeltaPETCO2, L min(-1)Torr(-1)) was measured by a progressive hypercapnic method. HCVR, was greater (p<0.001) in the obese men (2.68+/-0.78) than in the lean men (1.4+/-0.45) as was HVR (p<0.05) (1.26+/-0.65 versus 0.71+/-0.43, respectively). The difference (DeltaSaO2, 4.30+/-3.69 and 10.54+/-3.45 in the lean and obese men, respectively, p<0.01) between daytime (86+/-1 and 86+/-1%) and nighttime SaO2 (81+/-3 and 76+/-4%) at a simulated altitude of 3658 m was significantly (p<0.05) correlated with both HVR (r=0.51) and HCVR (r=0.48). These results suggest that chemosensitivity in mildly obese men is increased, not blunted. Furthermore, otherwise healthy, obese individuals have the potential for significant desaturation during sleep at high altitude possibly due to exaggerated sleep-disordered breathing.  相似文献   
84.
Lu S  Ge G  Qi Y 《Archives of virology》2004,149(11):2187-2198
Summary We present evidence that actin is necessary for the successful assembly of HaNPV virions. Purified nucleocapsid protein Ha-VP39 of Heliothis armigera nuclear polyhedrosis virus (HaNPV) was found to be able to bind to actin in vitro without assistance, as demonstrated by Western blot and isothermal titration calorimeter. H and binding constants (K) detected by isothermal titration calorimeter strongly suggested that Ha-VP39 first binds actin to seed the formation of hexamer complex of actin, and the hexamers then link to each other to form filaments, and the filaments finally twist into cable structures. The proliferation of HaNPV was completely inhibited in Hz-AM1 cells cultivated in the medium containing 0.5µg/ml cytochalasin D (CD) to prevent polymerization of actin, while its yield was reduced to 10–4 in the presence of 0.1µg/ml CD. Actin concentration and the viral DNA synthesis were not significantly affected by CD even though the progeny virions assembled in the CD treated cells were morphologically different from normal ones and resulted in fewer plaques in plaque assayThe authors equally contributed to the work.The authors equally contributed to the work.  相似文献   
85.
测量70个西藏现代藏族人颅40项指标;计算指数16项;根据指数确定颅型,额型,颌型,眶型,鼻型与腭型;进行数理统计;观察性别差异,发现男发性间各测量值差显著,  相似文献   
86.
Different scaffolds have been designed for ligament tissue engineering. Knitted scaffolds of poly-L-lactic acid (PLLA) yarns and co-polymeric yarns of PLLA and poly(glycolic acid) (PLGA) were characterized in the current study. The knitted scaffolds were immersed in medium for 20 weeks, before mass loss, molecular weight, pH value change in medium were tested; changes in mechanical properties were evaluated at different time points. Results showed that the knitted scaffolds had 44% porosity. There was no significant pH value change during degradation, while there was obvious mass loss at initial 4 week, as well as smooth molecular weight drop of PLLA. PLGA degraded more quickly, while PLLA kept its integrity for at least 20 weeks. Young's modulus increased while tensile strength and strain at break decreased with degradation time; however, all of them could maintain the basic requirements for ACL reconstruction. It showed that the knitted polymeric structures could serve as potential scaffolds for tissue-engineered ligaments.  相似文献   
87.
Rao ZR  Ge X  Qiou JY  Yang T  Duan L  Ju G 《Neuroscience research》2000,38(2):139-146
Forebrain heat shock protein 70 (HSP70) immunohistochemical reactivity was investigated in rats subjected to gamma knife irradiation focusing on the right caudate putamen nucleus. The forebrain sections of all experimental animals were processed with anti-HSP70 antiserum and then by avidin-biotin peroxidase complex immunohistochemistry after gamma ray irradiation with a dose of 100Gy and they each survived for different times (from 30 min to 30 days). Some neurons, glial cells, and endothelial cells were HSP70-like immunoreactivity (HSP70-LI) positive. HSP70-LI was mainly distributed in the target area of irradiation, as well as in non-target regions, e.g. the cortex, hippocampus, and hypothalamus, etc. The expression and change of HSP70-LI from 3 h to 30 days after irradiation followed the following rules: (1) Within 3 to 24 h, the dilated vessels with HSP70-LI endothelial cells were found at first, and a few lightly stained HSP70-LI neurons and glias were observed in the target and non-target regions; (2) In 3-7 days, darkly stained HSP70-LI neurons and glias were apparently increased and formed an expression peak. From 14 to 30 days, HSP70-LI cells were distinctly decreased and became weakly stained or negative. These results suggested that although the irradiation target of the gamma knife was localized, the response to irradiation occurred extensively.  相似文献   
88.
目的 探讨能否直接利用肿瘤细胞膜进行表皮生长因子受体 (Epidermalgrowthfactorreceptor,EGFR)催化活性检测。方法 首先筛选出EGFR基因表达水平相对较高的细胞株MDA MB 2 31,通过差速离心制备细胞膜 ,采用Westernblotting检测EGFR催化磷酸化的程度。结果 底物被磷酸化 ,加入特异性拮抗剂AG14 78后 ,磷酸化被抑制。结论 利用肿瘤细胞膜检测EGFR活性的设想是成立的 ,并且其方法简便、经济。  相似文献   
89.
目的 观察两种浓度的臭氧(03)对实验兔骨骼肌组织的病理变化的影响,以评估臭氧对肌纤维的氧化程度.方法 10只实验兔随机分为A、B两组.随机选择一侧大腿肌肉注射臭氧-氧气混合气体,A组为浓度50μg/ml,B组为浓度30μg/ml两组分别注射5 ml气体.注射臭氧后0.5、2 h和2周后分别对臭氧注射点、旁开1 cm和2 cm取活检组织行病理学光镜检查,对侧大腿相对应部位取活检作空白对照.结果 与空白对照组比较,病理光镜下显示A、B两组注射臭氧后0.5 h注射点、旁开1 cm见肌细胞肿胀,间隙变窄或不清,肌细胞边界不清,横纹紊乱,部分肌细胞坏死溶解,空泡变性;2 h后注射点、旁开1 cm处在肌细胞坏死溶解的基础上出现了肌细胞间隙和血管内炎症细胞浸润;2周后注射点、旁开1 cm切片显示肌细胞明显萎缩,大量纤维组织增生,部分伴有玻璃样变.上述3个时点的注射点旁开2 cm病理切片均未见异常.结论 两种浓度的臭氧肌肉注射后会产生程度相当的肌细胞损害,范围半径约2 cm,可能对炎性肌细胞或肌纤维化组织起治疗作用,2周后纤维组织损伤修复.  相似文献   
90.
研究四种类型热塑性聚合物的6种常见医用输液接头材料对抗肿瘤药物溶剂的耐受性。将这些材料的标准测试样条固定在弯曲应变为1.5%的自制夹具上,分别浸泡在Etoposide?药物溶剂、Busulflex?药物溶剂或DMSO(以50%为例)等3种抗肿瘤药物溶剂,然后观察试样的外观,测试试样的拉伸强度、断裂伸长率和缺口冲击强度等性能的变化情况,采用定量化的评分,对6种材料的抗肿瘤药物溶剂的耐受性进行了评价。结果表明,两款超硬质热塑性聚氨酯(TPU)材料对三种抗肿瘤药物溶剂的耐受性均优于其他4种评价的材料,为接触抗肿瘤药物类的医疗器械产品的较优选择,比如PICC,CVC,输液器等。  相似文献   
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