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81.
雪旺细胞源运动神经营养蛋白对周围神经再生的影响   总被引:3,自引:0,他引:3  
目的:研究雪旺细胞源运动神经营养蛋白对周围神经再生的影响。方法:60只SD大鼠均分为3组,A和B组分别在桥接于大鼠右侧坐骨神经断端之间的硅胶管内加入26KD和50KD的雪旺细胞源运动神经营养蛋白,C组加PBS液作为对照。术后1~6月每隔半月测定实验侧坐骨神经功能指数,术后3月测定实验侧坐骨神经的电生理和形态学指标。结果:A和B组实验侧坐骨神经的功能指数、电生理和形态学指标与C组比较,差别有非常显著性。结论:26KD和50KD雪旺细胞源运动神经营养蛋白对周围神经再生有促进作用。  相似文献   
82.
磷脂酶C与生殖   总被引:2,自引:0,他引:2  
磷脂酶C(PLC)是磷脂酰肌醇信号转导途径中一个关键酶。目前确认的哺乳类PLC共有PLC β、PLC γ、PLC δ、PLC ε和最近新发现的PLC ζ 5种亚型 ,12种同工酶。不同亚型的结构、调控和组织分布各有差异。PLC在调控信号转导通路中的特性使其在顶体反应、卵子激活中发挥了巨大的作用。本文综述了PLC家族 5种亚型的结构、调控机制及PLC在男性生殖领域的相关内容 ,包括PLC引起卵子发生Ca2 + 振荡、激活卵子、促进胚胎发育等 ,并进一步探讨了PLC在临床上可能的应用前景。  相似文献   
83.
效应室浓度作为目标浓度靶控输注异丙酚的脑摄取研究   总被引:9,自引:0,他引:9  
OBJECTIVE: To study the correlation between the effect compartment concentration (ECC) and the brain uptake of propofol during sedation by target-controlled infusion (TCI). METHOD: Twelve ASA physical status I to II patients with neither cardiac nor intracranial diseases were scheduled for elective abdominal operation. Computer-assisted target-controlled infusion of propofol was performed for general anesthesia in all patients with the target ECC set at 4.0 microgram/ml. The plasma propofol concentrations were measured simultaneously from the radial artery and the jugular bulb at different time points by high performance liquid chromatography (HPLC), and the area under time-concentration curve (AUC(a-jv)) was calculated. RESULT: Before reaching the target propofol concentration of 4.0 microgram/ml (4.7+/-0.16 min), EEC was positively correlated with AUC(a-jv) (r(ECC-AUC)=0.977, P<0.001), but neither the arterial (Ca) nor jugular bulb propofol concentrations (Cjbv) showed such relation to AUC(a-jv) (r(Ca-AUC)= 0.054, P=0.92; r(Cjbv-AUC)=0.335, P=0.516). When ECC was controlled at 4.00 microgram/ml by TCI, Ca was comparable with Cjbv (P=0.512). Positive correlation was noted between AUCa-jv and ECC (r(ECC-AUC)=0.942, P<0.005) after the termination of infusion till the consciousness recovery of the patients, and Ca and Cjbv showed similar correlation with AUC(a-jv) (r(Ca-AUC)=0.986, P<0.001; r(Cjbv-AUC)=0.974, P<0.001). CONCLUSION: During TCI of propofol with ECC as the target concentration, ECC is significantly correlated with AUC(a-jv) to reflect the dynamic changes in cerebral propofol uptake.  相似文献   
84.
目的:观察地震灾害对分娩的影响。方法:对我院2008年5月12日至2008年6月12日在地震期间分娩的216例产妇进行回顾性分析。结果:阴道分娩率较地震前比较明显上升,剖宫产率明显下降。结论:地震灾害致孕妇的心理发生变化,导致阴道分娩率上升剖宫产率明显下降。  相似文献   
85.
宫腔镜联合腹腔镜检查不孕症168例分析   总被引:6,自引:3,他引:3  
目的探讨宫、腹腔镜联合检查不孕症的诊断价值.方法回顾性分析1999年6月~2003年10月宫、腹腔镜联合检查168例不孕症的临床资料.结果宫腔镜检查发现异常宫腔79例(79/168,47.0%),其中子宫内膜增生、内膜息肉46例(46/79,58.2%).腹腔镜检查发现盆腔器质性病变99例,其中慢性盆腔炎、子宫内膜异位症和多囊卵巢共85例(85/99,85.9%);宫、腹腔镜检均正常15例,均异常39例.宫腔镜下行输卵管通畅检查,输卵管单侧或双侧不通90例(90/168,53.6% );腹腔镜检查输卵管单侧或双侧不通78例(78/168,46.4%).结论宫腔镜联合腹腔镜检查不孕症能够提供准确的诊断依据.  相似文献   
86.
87.
目的 探讨绝经后妇女IUD取器前超声测定环距是否与取器难度有关.方法 对放置IUD绝经后妇女取器前行超声测定环距,分环距>1.5cm,1.5-1.0cm,≤1.0cm三组,比较手术难度,并对绝经≤12月IUD组与对照组的围绝经期综合症、老年性阴道炎、阴道炎、子宫蒌缩情况进行分析.结果 环距≤1cm组手术难度显著增加(P<0.05).绝经≤12个月IUD组与对照组在围绝经综合症、老年性阴道炎、阴道炎、子宫萎缩发生率方面均无显著差异,(P>0.05).结论 绝经后妇女取器前超声测定环距对估计手术难度有一定意义,尤其当环距≤1cm,手术困难明显增加.绝经≤12月IUD对健康没有直接影响.  相似文献   
88.
雷米芬太尼控制性降压对颅脑手术患者血液动力学的影响   总被引:6,自引:2,他引:4  
目的观察神经外科手术中雷米芬太尼控制性降压对血液动力学的影响。方法20例ASAⅠ~Ⅱ级择期行颅脑手术患者,采用全凭静脉复合麻醉,术中持续泵注雷米芬太尼行控制性降压,维持MAP 60~70 mmHg,观察降压前(T0)、降压达目标时(T1)、维持降压15 min(T2)、30 min(T3)、停降压15 min(T4)3、0 min(T5)6个时点的MAP、HR、心输出量(CO)、心脏指数(CI)、心室收缩加速度指数(ACI)、左心做功(LCW)、外周血管阻力(SVR)的变化。结果与T0比较,T1、T2、T3时点MAP、SVR、LCW均显著降低(P<0.01);HR亦明显减慢(P<0.05);CO、CI、ACI无明显降低。结论神经外科手术中行雷米芬太尼控制性降压安全、有效,具有对心功能影响小的优点。  相似文献   
89.
Inbred mouse strains have different numbers of midbrain dopaminergic neurons; for example, BALB/cJ mice have 20–25% more neurons than CBA/J mice. As the number of cells decrease, for example in Parkinson's disease and in animals with midbrain dopaminergic cell lesions, the activity of their remaining cells increases. The purpose of the present experiment was to determine whether the functional properties of dopaminergic neurons in the ventral tegmental area (nucleus A10) differ in inbred mouse strains which possess different numbers of cells. The firing rate and autoreceptor sensitivity of A10 dopaminergic cells were examined in the in vitro slice preparation in BALB/cJ, C3H/HeJ, CBA/J, and DBA/2J mouse strains. It was observed that the autoreceptors on mouse dopaminergic neurons exhibit pharmacological properties of dopamine autoreceptors; activation of the autoreceptor produced a marked inhibition (50–70%) in cell firing rate by quinpirole (10−8 M), LY-141865 (10−7 M), (+)-3-(3-hydroxyphenyl)-N-n-propyl-piperidine (10−6 M), propyl-norapomorphine (10−5 M) and dopamine (10−4 M), and this inhibition was blocked or reversed by specific dopamine D2 receptor antagonists [(−) sulphide and spiroperidol, 10−6 M]. The baseline firing rates of the A10 cells did not differ among the four inbred strains [range 2.5 ± 0.2 (C3H/HeJ)−3.4 ± 0.3 (CBA/J) spikes/s ±SEM], and there was no significant difference in autoreceptor sensitivity among the mouse strains as assessed either by superfused dopamine (inhibitory dose 50% ≈150 μM), or by superfused quinpirole (inhibitory dose 50% ≈10 nM). These data indicate that differences in A10 cell numbers of 30% do not significantly influence the baseline firing rate or autoreceptor sensitivity of the cells.  相似文献   
90.
OBJECTIVES: Radiopacity is a desirable property for most intra-oral materials. There are established ISO and ANSI/ADA protocols for determining radiopacity using film-based radiography. However, these methods are not always followed by researchers. This study aims to adapt those procedures by using digital radiography, a simplified stepwedge, and examine the effects of target distance and exposure time choice. METHODS: One millimetre thick samples of three dental materials were prepared by placing the materials into a 1.00 mm thick washer sandwiched between two glass slides. The samples were digitally radiographed alongside a stepwedge of aluminum alloy 1100 with an X-ray unit at 70 kVp using five different target distance/exposure time combinations. For each combination, the grey scale values of various thicknesses of the stepwedge were converted into absorbencies and plotted against their thickness. These plots were then linearly regressed in order to correlate absorbance with a thickness of aluminum for each target distance/exposure time combination. The absorbencies of each sample were then converted into radiopacities using these correlations. RESULTS: The correlations between the absorbance of the stepwedge and its thickness were highly linear. This linearity allows the correlation to be accurately deduced from fewer data points than required by the ISO and ANSI/ADA protocols. Varying exposure time did not significantly affect the mean radiopacity measured at a target distance of 30 cm. Varying the target distance did not significantly affect the measured radiopacity as long as the samples were properly exposed. SIGNIFICANCE: A simplified, consistent digital method for determining radiopacity is presented.  相似文献   
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