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31.
Objective To evaluate the association of 2616c/T polymorphism in iron regulatory protein 2(IRP2)gene with Alzheimer disease(AD)and Vascular dementia(VD).Methods In this study,281 patients with AD,60 with VD,and 285 normal aged were recruited.The 2616C/T polymorphism in IRP2 gene was analyzed by using polymerase chain reaction-restriction fragment length polymorphism.And the cognitive function was assessed with the Mini-Mental State Examination(MMSE).Results (1)No significant difieFences were demonstrated in IRP2 genotype or allele frequencies between AD patients and controls(χ2=2.46,P=0.292;χ2=2.17,P=0.141 respectively).However,when AD patients were stratified by disease severity.the frequency of T allele carriers in the moderate to severe AD patients was 78.0%,significantly higher than that in controls(69.8%;χ2=4.106,P<0.05).Logistic regression analysis demonstrated that the age-,sex-and ApoE-adiusted OR of modcrate to severe AD patient with T allele was 1.62(95% CI=1.03-2.54).The frequency of T allele carriers or T allele in VD patients was higher than that of controls,but the difference was not statistically significant(P>0.05).(2)The frequency of tit genotype or T allele in the moderate to severe AD patients was significantly higher than that in mild AD patients(25.8%vs.12.5%,χ2=5.477,P<0.05;51.9%vs.40.3%,χ2=5.803,P<0.05 respectively).(3)MMSE scores of the AD patients with TT genotype was significantly lower than ones with CC or CT genotype(P=0.028;P=0.014 respectively).Conclusion The 2616C/T polymorphism in the IRP2 gene is possibly associated with moderate to severe AD.but not associated with VD.And the TT genotype may be a risk factor for cognitive impairment of patients with AD in Chinese Han.  相似文献   
32.
目的:观察和探讨两种印模技术对单个前牙烤瓷冠颈缘外观的改善效果。方法:40位患者用简易印模技术制取印模,制作93件镍铬合金烤瓷瓷冠,设为实验组,另35位患者以常规印模技术制取印模,制作71件镍铬合金烤瓷瓷冠,设为对照组。观察两组戴冠当时与两年后的颈缘适合性、颜色、牙龈形态与健康情况。结果:试验组有98%的合金瓷冠具有优良的边缘适合性,仅2件(2%)出现颈缘黑线,与对照组相比有显著差异(P<0.05)。结论:简易印模技术能更好的保证工作区模型的准确度,从而有效地改善了镍铬合金烤瓷冠颈缘的美观与龈组织的健康。  相似文献   
33.
目的 探讨三氧化二镍(Ni2O3)对人肺成纤维细胞(human lung fibroblasts,HLF)的DNA损伤作用以及Na2SeO3的保护作用。方法 应用单细胞凝胶电泳(single cell gel electrophoresis,SCGE)检测DNA损伤。结果 Ni2O3 处理HLF细胞4 h,SCGE检测出DNA损伤程度高于对照组,差异有显著性(P<0.01)。而Ni2O3 Na2SeO3 处理组DNA损伤程度低于Ni2O3 组,差异有显著性(P<0.01)。结论 硒可抑制镍诱导的人肺成纤维细胞的DNA损伤。  相似文献   
34.
三维重建单(双)靶点定向置管引流术治疗高血压壳核出血   总被引:1,自引:0,他引:1  
目的回顾性分析三维重建单(双)靶点定向置管引流术治疗高血压壳核出血的疗效,验证该方法的有效性和可行性。方法将133例壳核脑出血病人的CT定位扫描资料输入计算机工作站,对血肿进行三维重建,根据血肿量的大小和形状设计1~2个靶点和引流管路径。应用立体定向技术将引流管(外径5mm,内径3mm)送至颅内预定靶点,术中应用10ml注射器轻柔抽吸血肿液化部分,术后将尿激酶(1~2万IU)注入血肿腔内,夹闭引流管2h后自然引流,每12h重复1次。复查CT证实剩余血肿量为最初的10%~15%时拔除引流管。结果平均置管1.5 d(1~3d),平均血肿排空率92.8%。术后1个月病死率6.0%,远期随访(平均22个月)病死率11.3%,优良率74.4%。结论该方法治疗高血压壳核脑出血,血肿排空较彻底,疗效可靠,尤其适用于血肿量较大(>25ml)且形态不规则的颅内血肿。  相似文献   
35.
比较69例冠心病患者多巴酚丁胺负荷99mTc甲氧基异丁基异腈(MIBI)心肌断层显像与82例运动试验99mTcMIBI心肌断层显像的结果,以探讨它们对冠心病的诊断价值。结果表明:以冠状动脉造影结果为标准,多巴酚丁胺负荷诊断冠心病的敏感性和特异性分别为912%和800%,运动试验分别为894%和829%。多巴酚丁胺负荷检出冠状动脉病变的敏感性和特异性:左前降支为781%和913%,回旋支为667%和982%,右冠状动脉为100%和837%;运动试验分别为783%和911%,600%和968%,909%和850%,差异均无显著性(P>005)。提示两者结果相近,对于不能进行运动试验的病人,多巴酚丁胺试验是一种有价值的诊断冠心病的方法。  相似文献   
36.
R Tamura  T Ono  M Fukuda  H Nishijo 《Hippocampus》1992,2(3):287-306
The purpose of this study was to investigate, during the performance of an object discrimination task, responses of neurons in the monkey hippocampal formation to the sight of several objects that have biological meaning, and compare these responses with those of amygdalar neurons studied previously using the same task. Neuronal activity in the hippocampal formation of conscious monkeys was recorded during performance of a task that led to presentation of familiar rewarding, familiar aversive, or unfamiliar objects. Of 864 neurons recorded in the hippocampal formation and adjacent cortices, 160 (18.5%) responded to the sight of a certain object(s). Responses to the sight of different kinds of objects were analyzed in detail. Nondifferential neurons (n = 73) responded to different objects with no significant difference in response magnitudes, and differential neurons (n = 87) responded to different objects with different response magnitudes. Of the differential neurons, 23 responded more strongly to rewarding objects than to other objects (rewarding-object-dominant neurons), but the magnitude of responses to objects did not necessarily correlates with the order of preferences to the objects as determined from observation of animal behavior. Aversive-object-dominant neurons (n = 13) responded more to aversive objects than to other objects. Unfamiliar-object-dominant neurons (n = 7) responded more to unfamiliar objects than to familiar objects. Selective neurons (n = 10) responded selectively to only one object or one category of objects. Fourteen of the rewarding- or averse-object-dominant neurons were tested in extinction or reversal trials. In 12 of 14 neurons, responses to a rewarding or aversive object did not change, or slightly weakened, in extinction or reversal trials. The results suggest the following. (1) Responses of rewarding- or aversive-object-dominant neurons may be involved in object-reward or object-aversion association. However, responses of many of these neurons might reflect past inputs to reinforcement rather than extant emotional processing. (2) Responses of unfamiliar-object-dominant neurons may be involved in recognition of objects based on their familiar or unfamiliar aspects. These results are further discussed and compared with responsiveness of amygdalar neurons.  相似文献   
37.
目的 探讨N -乙酰半胱氨酸 (NAC)治疗不同病期慢性阻塞性肺疾病 (COPD)的疗效。方法  49例稳定期、急性发作期COPD患者 ,随机分为观察组 (2 5例 )和对照组 (2 4例 ) ,观察组除给予常规治疗外 ,加用NAC(每次 2 0 0mg ,3/d ,连用 2个月 ) ;对照组仅给予常规治疗。治疗前后观察所有患者外周血淋巴细胞DNA损伤程度。结果 治疗前后比较 ,观察组稳定期、急性发作期DNA损伤明显降低 ,差异有显著性 (P <0 .0 5)。对照组稳定期DNA损伤程度亦有一定程度的改善 ,但差异无显著性 (P >0 .0 5) ,急性发作期DNA损伤程度降低 ,差异有显著性 (P <0 .0 5)。结论 COPD患者体内存在氧化 -抗氧化失衡 ,抗氧化治疗可降低COPD患者外周血淋巴细胞DNA损伤程度 ,急性发作期出现氧化应激。  相似文献   
38.
目的探讨GABA受体基因GABBR1多态性在特发性癫痫发病(IGE)中的作用。方法采用PCR、琼脂糖凝胶电泳技术分析46例IGE患者(研究组)rs3025627、rs3025628和rs29220基因型频率变化,并与50例健康查体者(对照组)比较。结果观察组与对照组rs3025627TT基因型频率分别为0.362、0.245,P〈0.01,rs3025627AT基因型频率分别为0.354、0.447,P〈0.05。两组rs3025628和rs29220基因型频率无统计学差异(P〉0.05)。结论rs3025627基因型频率改变可能是导致GABBR1基因外显子7在IGE病中起作用的原因。  相似文献   
39.
We studied neuromuscular transmission in 16 patients with prior poliomyelitis by measuring single fiber electromyographic (SFEMG) jitter. This was compared with 3 indirect methods of assessing reinnervation: SFEMG fiber density, macro EMG, and the presence of fiber type grouping on muscle biopsy. In patients with acute poliomyelitis before the age of 10, there was a positive correlation between the extent of neuromuscular transmission impairment, demonstrated by increased SFEMG jitter, and the enlargement of the motor unit, as indicated by increased fiber density, increased macro EMG signals, and fiber type grouping on muscle biopsy. However, there was no correlation between any of these parameters and the presence or absence of new symptoms of weakness. These findings suggest that impaired neuromuscular transmission is most common in patients with prior poliomyelitis whose motor units have been maximally enlarged by axonal sprouting, but is independent of the presence or absence of new symptoms of weakness.  相似文献   
40.
均一吸收体中SPECT重建多解性的探讨   总被引:1,自引:0,他引:1  
通过对重建图像噪声特性的分析,间接证明SPECT的解具有多样性。分别用TretiakMetz、Gulberg、富谷武浩等推导的3种等价重建方法和Belini等推导的重建方法,经计算机模拟重建衰减均匀分布的图像,先预置相同的重建图像的空间分辨率,再比较它们的噪声特性。两种方法重建图像的噪声分布:前者近图像边缘时增大,而后者减小,从而间接证明在假定均匀衰减条件下,SPECT的重建有多解性。  相似文献   
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