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51.
目的动态观察Zephyr5826起搏器心房自动阈值管理(ACM)功能的开启情况、准确性及安全性。方法选取置入Zephyr5826起搏器患者68例,于置入术后第1,7天及1,2,3,6个月时随访程控,观察ACM功能的开启情况,手工测试心房起搏阈值并与ACM功能测定的值进行比较。结果 68例均完成随访。随访期内35例(51.50%)成功开启ACM功能,其中术后第1,7天及1,2,3个月时开启例数分别为14例(20.6%)、21例(30.9%)、26例(38.2%)、28例(41.2%)和32例(47.1%)。手工测试与ACM测试的心房阈值无差异。33例因起搏器自动测定心房刺激除极波(ER)过小不推荐开启ACM功能。随访期间心电图及动态心电图(Holter)均未见心房失夺获及感知不良。与普通电压和高电压起搏相比,自动阈值管理功能在心房输出方面分别节省50%,88%的能量消耗。结论 Zephyr5826起搏器ACM功能可以安全有效的应用低能量起搏心脏。部分患者术后因起搏器测定心房ER过小未能开启ACM功能,但在随访过程中ACM的开启比例逐渐升高。  相似文献   
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IntroductionAlthough balance training is considered the most effective treatment for balance impairments in Parkinson’s disease (PD), few studies have examined if learning for balance control remains intact with PD. This study aimed to determine if learning for automatic postural responses is preserved in people with PD.MethodsEleven participants with moderate PD (68 ± 6.4 years; H&Y: 2–3) on their usual medication maintained balance on a platform that oscillated forward and backward with variable amplitude and constant frequency. Participants completed 42 trials during one training session, and retention and transfer tests following a 24-h delay. Performance was measured by comparing spatial and temporal measures of whole-body centre of mass (COM) with platform displacements. Learning was compared between participants with PD and previously reported, age-matched older adults (Van Ooteghem et al., 2010).ResultsAlthough postural responses in participants with PD were impaired compared to control participants, a majority of PD participants improved their postural responses with practice as revealed by reduced COM displacements and improved phase relationships between COM and platform motion. Rates of improvement were comparable between groups demonstrating preserved adaptive capacity for participants with PD. Similar to control participants, the PD group moved toward anticipatory COM control as a strategy for improving stability, exhibited short-term retention of performance improvements, and demonstrated generalizability of the learned responses. Rate of improvement with practice, but not retention, was related to severity of motor impairments.ConclusionsPatients with moderate PD on medication demonstrate retention of improvements in automatic postural responses with practice suggesting that intrinsic postural motor learning is preserved in this group.  相似文献   
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Enzyme enhancement therapy (EET) for Fabry disease involving imino sugars has been developed and attracted interest. It is thought that imino sugars act as pharmacological chaperones for wild-type and mutant α-galactosidases (GLAs) in cells, but the mechanisms underlying the molecular interactions between the imino sugars and the enzyme have not been clarified yet. We examined various kinds of imino sugars and found that galactostatin bisulfite (GBS) inhibited GLA in vitro and increased the enzyme activity in cultured Fabry fibroblasts as in the case of 1-deoxygalactonojirimycin (DGJ). Then, we analyzed the molecular interactions between the imino sugars and recombinant human GLA by means of isothermal titration calorimetry and surface plasmon resonance biosensor assays, and first determined the thermodynamic and binding-kinetics parameters of imino sugar and GLA complex formation. The results revealed that DGJ bound to the enzyme more strongly than GBS, the binding of DGJ to the enzyme protein being enthalpy-driven. In the case of GBS, the reaction was mainly enthalpy-driven, but there was a possibility that entropy-driven factors were involved in the binding. Structural analysis in silico revealed that both the chemicals fit into the active-site pocket and undergo hydrogen bonding with residues comprising the active-site pocket including the catalytic ones. The side chain of GBS was oriented towards the entrance of the active-site pocket, and thus it could be in contact with residues comprising the wall of the active-site pocket. Thermodynamic, kinetic and structural studies should provide us with a lot of information for improving EET for Fabry disease.  相似文献   
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自动体外除颤器临床应用的研究   总被引:1,自引:0,他引:1  
目的探讨自动体外除颤器(AED)临床应用中对室性心动过速(室速)/心室颤动(室颤)的诊断能力、治疗效果和存在的问题。方法应用Power Heart全自动体外除颤器对入选的21例室速、室颤患者进行监测。结果全组发生需电击的心律失常108次,实施自动电除颤99次,发放的电除颤转复成功率96.97%(96次),无效率3.03%(3次,含1次心房扑动误治疗),误治疗率2.02%(2次)。AED电除颤成功治疗后缓慢性心律失常发生率17.71%(17次)。4例患者AED治疗后出现窦性心动过速和室速、室颤发作频度增加,发作间期缩短的现象。结论AED能够有效地自动诊断和治疗室速、室颤,但临床应用仍有较多问题需注意。  相似文献   
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目的建立电导滴定法测定磁性微球表面微量氨基的化学计量点选择新方法,定量分析其氨基含量,为其表面修饰及偶联奠定基础。方法观察不同因素对滴定结果准确度的影响,在此基础上采用电导滴定法对磁性微球表面氨基进行定量测定,比较曲线拟合及电导率的变化率(ΔK)确定化学计量点2种不同方法对滴定结果的影响。结果建立了更为直接、客观的电导滴定法测定磁性微球表面微量氨基的新方法。利用滴定曲线拟合计算氨基化磁性微球表面氨基含量为(35.05±14.18)μmol/g(RSD=40.47%,n=5);而用ΔK确定化学计量点计算氨基化磁性微球表面氨基含量为(51.38±2.91)μmol/g(RSD=5.66%,n=5),后者的测定精度明显高于前者。结论利用电导率的变化率(ΔK)确定滴定拐点更为直接客观,降低了主观误差,测定精度较高。  相似文献   
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In 14 healthy male volunteers, we studied the influence of acute mental (=psychological) stress induced by performing mental arithmetic and solving anagrams against a financial reward on endogenously stimulated gastric acid output. Personality factors were determined by the Personality Research Form. Acute mental stress significantly (P<0.05) increased systolic blood pressure (+8.9±2.0 mm Hg±sem) and heart rate (+5.3±1.6 beatslmin). The mean gastric acid output during the mental stress period (17.9±2.7 mmol/32 min) did not significantly differ from pre- (16.9±2.3 mmol/32 min) and poststress (18.1±2.2 mmol/32 min) values. However, detailed analysis revealed that mental stress induced contrary changes of gastric acid output in different subjects. About half the individuals reacted with a decrease (up to 60%) and the other half with an increase (up to 60%) in acid output. In some individuals the changes of gastric acid output were very small. By multiple correlations, impulsivity was identified as the personality trait with the highest correlation coefficient (r=0.82) with changes of gastric acid output during the acute mental stress period. During the mental stress period, gastric acid output increased in subjects with high scores on the impulsivity scale, but significantly decreased in those with low scores. We conclude that (1) there is a great individual variability in gastric acid response to acute mental stress, and (2) this variability may be partly attributed to differences in personality traits.  相似文献   
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目的 了解糖尿病患者的自主神经功能及其对肛管直肠运动的影响.方法 对26例糖尿病患者和15名健康志愿者分别行自主神经功能测定(标准心血管反射试验)和肛管直肠压力测定.结果 糖尿病自主神经功能异常者占95%,其交感、副交感和自主神经功能计分均显著高于健康对照组,副交感神经功能受损更为明显.肛管直肠压力测定显示直肠静息压、肛管静息压及肛管最大自主收缩压降低,肛管直肠协调功能障碍,直肠敏感性降低.结论 糖尿病患者有明显的自主神经功能异常,其中副交感神经功能受损更为明显,且存在肛管直肠动力障碍.糖尿病患者肛管直肠动力障碍与自主神经功能受损有关.  相似文献   
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