基于晶体振荡器的MIT系统激励源设计及其实现

目的: 设计一种应用于磁感应断层成像技术(magnetic induction tomography,MIT)系统的10 MHz高性能激励源,以提高MIT系统的测量精度. 方法: 根据高频电子电路设计原理及其电磁屏蔽技术,选用高频率精度和稳定性的恒温晶体振荡器,设计和实现了高性能激励源.结果: 激励源稳定输出10 MHz正弦信号,频率稳定度优于1×10-7水平,杂波抑制和谐波抑制分别达到90 dBc和45 dBc,负载时输出电压峰峰值为12 V,最大输出功率为1.3 W. 结论: 设计的激励源提供了高频率稳定性和高信噪比的激励信号,为高精度的MIT测量奠定了基础.     

起搏电极导线脱位的临床因素及心电变化分析

目的:探讨电极脱位的原因及心电图检查方法.方法:回顾性分析起搏电极导线脱位患者26例的临床资料.结果:本组患者26例中,29根电极导线脱位,双极电极导线17根,单极电极导线12根,心室电极导线18根,心房电极导线11根,心电图表现为心房、心室间断起搏或不起搏,感知功能正常或感知不良,或异处着床并间歇起搏.结论:双极电极...     

非接触磁感应脑阻抗断层成像系统激励源设计

目的：设计适合非接触磁感应脑阻抗断层成像系统工作的激励源和感应线圈 ，为进一步了解生物组织电阻抗的行性打下良好的基础。方法：基于高速电子电路设计技术，建立具有差分驱动模式、频率（1MHz-20MHz)和幅值均线性可调的信号源，分析测量结果，得出设计参数。测量并计算感应线圈参数，分析影响其特性的因素。结果：激励源的输出频率在10MHz时，带负载线圈稳定输出最大电压峰峰值12V,最大电流220mA，频率稳定度为0．5％，输出噪声电压有效值6．1mA，信噪比63dB。结论：本信号源性能满足试验要求，受外界电磁幅射干扰影响小，感应线圈设计合理，有利于进行检测试验，这些都为下一步成像打下良好的基础。     

植入型心律转复除颤器除颤电极导线功能故障的原因及处理

目的 探讨植入型心律转复除颤器（ICD）及心脏再同步化心律转复除颤器（CRT-D）除颤电极导线功能故障的发生率、可能原因及处理方法.方法 对166例植入ICD或CRT-D的患者进行长期跟踪随访,统计除颤电极导线功能故障发生率,分析其可能原因及处理方法.结果 166例患者中出现除颤电极导线功能故障5例,发生率为3.01%.其中电极导线绝缘层破裂1例,ICD导线功能障碍1例,R波感知逐渐降低3例.其中2例予以更换除颤电极导线,2例予以植入普通主动固定电极导线,余1例随访中待择期处理.结论 植入ICD或CRT-D的患者,除颤电极导线功能障碍可引起ICD不适当放电,随访中若发现除颤电极导线功能障碍,应及时更换导线.     

一种对玻璃微吸管电极抛光的装置及使用方法

目的 :对玻璃微电极尖端进行热抛光处理 ,以提高膜片钳实验中高阻抗封接的质量和成功率。方法 :用双相可控硅增加电流方法 ,完成低电压高电流输出 ;利用普通显微镜加以改造 ,在同一平面内观察电极尖端和电热丝情况。结果 :直流输出电压 6V ;直流输出电流 0～ 2 0A ;4 0× (物距 1cm)物镜 ;光镜和扫描电镜观察电极尖端平整、光滑。结论 :利用简单的双相可控硅增流技术和对普通生物显微镜的改造 ,可以制做出用于玻璃微电极尖端热抛光的装置。     

EIS检测电极屏蔽地环宽度对成像结果的影响

目的:评估电阻抗乳腺扫描(EIS)技术中检测电极阵列周围屏蔽地环大小对系统检测性能的影响,并针对64电极阵列提出合适的地环宽度.方法: 在64电极的物理模型中模拟人体乳腺组织分布,采用相同电极阵列、不同屏蔽地环宽度的检测电极,分别检测均匀背景溶液、同一体积和深度的琼脂目标体,对比测量结果.人为使用绝缘材料遮盖检测电极屏蔽地环,测量30例女性志愿者,观察地环屏蔽前后的数值变化.结果: 屏蔽地环宽度越小,电场边缘效应越明显,测量数据的离散性呈以下趋势:0 mm>2 mm>3 mm>5 mm>7mm.在临床检查中,屏蔽地环的不良接触同样影响EIS成像质量.结论: 电极屏蔽地环宽度大小对于EIS成像中检测性能的影响至关重要,介于5～7 mm之间的屏蔽地环宽度对于64电极阵列较为合适.     

一种经头静脉穿刺置入起搏器电极导线的新方法

目的:介绍一种经头静脉穿刺置入起搏器电极导线的新方法. 方法:对25例需安装双腔或三腔永久人工心脏起搏器的患者进行研究.分离、穿刺头静脉成功后置入导引钢丝,经钢丝置入直鞘管,直鞘管内再置入1～2根导引钢丝,撤出直鞘管,分别经各个导引钢丝置入2～3个可撕开鞘管并插入起搏电极导线.结果:22例成功置入2或3个可撕开鞘管并插入电极导线,无血肿、血/气胸、误穿锁骨下动脉等血管并发症发生,3例未能分离出头静脉,改为穿刺锁骨下静脉后置入电极成功.结论:新的穿刺方法及电极导线置入方法避免了常规穿刺锁骨下静脉各种相对严重的并发症;较常规头静脉切开、电极导线同时置入头静脉的方法,新方法使电极导线在各自鞘内操作更加准确、容易.但部分患者分离头静脉存在困难.     

植入型心律转复除颤器除颤电极导线故障观察

目的:探讨植入型心律转复除颤器(ICD)或心脏再同步化心律转复除颤器(CRT-D)除颤电极导线障碍的可能原因和提示指标.方法:对我院2000年至2011年125例植入ICD或CRT-D的病人进行随访.观察指标:导线阻抗、感知、阈值、VV间期以及非持续性室性心动过速(NSVT).统计除颤电极导线功能故障发生率,分析其可能原因.结果:125例病人中出现除颤电极导线功能故障7例,发生率为5.6％.其中电极导线绝缘层破裂1例,ICD导线微接触障碍1例,导线微损坏3例,导管头端跨心内外膜1例,导线老化1例.导线阻抗、感知、阈值、VV间期是除颤电极导线功能故障的敏感的提示指标.结论:植入ICD或CRT-D的病人,通过密切随访导线阻抗、感知、阈值和W间期能尽早发现除颤电极导线功能障碍,减少不恰当放电.     

主动固定电极导线脱位的临床特点及处理措施

目的主动固定电极导线广泛应用于临床,电极导线脱位是心脏起搏器置入术的严重并发症,文中旨在探讨主动固定电极导线脱位的临床特点及处理措施。方法回顾性分析1341例起搏器植入患者中,电极导线脱位的临床资料及处理措施。结果电极脱位患者12例,有13根电极导线脱位。其中9根主动固定电极导线脱位,包括心房主动电极2根及心室主动电极7根;3根主动固定电极导线脱位发生于术后1个月内,6根发生于术后1个月后。4根被动电极导线脱位,包括心房电极2根及心室电极2根,均发生于术后1个月内。所有脱位主动固定电极均被安全拔除。结论主动固定电极导线脱位发生率与被动电极相似,但远期脱位率呈增多趋势。在起搏器安装时要采取必要的措施预防电极脱位。     

心脏再同步治疗中电极起搏部位和模式

心脏再同步治疗(CRT)与传统起搏治疗在适应证和植入技术上有很大不同.CRT治疗伴有收缩不同步的心衰患者,通常需要经静脉植入3根电极导线.其中通过冠状静脉窦植入左室电极导线来起搏左室,其起搏部位在CRT治疗中起相当重要的作用.有时还需寻求其它起搏模式,比如经胸植入左室电极导线来弥补冠状窦和静脉分支解剖所造成的治疗局限.除此之外,对右房、右室电极导线部位及起搏模式在CRT治疗中所起的作用也在进行各种优化探索.     

Value of D-Dimers in patients with acute aortic dissection

Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P ＜ 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (＞0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P ＜0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P ＜ 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.     

Research of combined liver-kidney transplantation model in rats

Objective： To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods： SD rats served as both donors and recipients. 4℃ sodium lactate Ringer＇s was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava （IVC） inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results： Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion： This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment.     

Development on Adjustable Calibration Marker for Shock Wave Focus

Shock wave lithotripsy （SWL） is a treatment of choice for upper urinary stones. However, this procedure is inappropriate for obese patients because the focus is often unable to reach the target owing to the limited focal distance in shock wave source. Although treating such patients in a blast path may increase the application length of shock wave source, it＇s difficult to find this path on the lithotripter monitor. For this reason, we invented an adjustable calibration marker in order to set an effective focus in the shock wave hath.     

Study on the TCM Pathogenesis of Angiopathic Complications of Type II Diabetes

Excess production of reactive oxygen species(ROS)of mitochondrion mediated by hyperglycemia is the common pathogenesis of angiopathic complications of diabetes.TCM holds that the damp from the dysfunction of spleen.kidney and liver is the causative factor of complications of diabetes.This is similar to the mechanism of Ros resulting in angiopathic complications of diabetes.When the angiopathic complications of type II diabetes mellitus(T2DM)are difierentiated as caused by turbid damp in TCM can be explained as ROS.Since the obstruction of pathogenic damp in channels and collaterals is said to be the main pathogenesis,the treating principle should be dissolving the damp to remove the obstruction.     

Leptin, Ghrelin and TNF-α before and after Hypo-caloric Traditional Chinese Diet and Auricular Acupuncture

INTRODUCTION Obesity is a complex emergent problem, which can be possibly solved not only by the diet but also by the life style and promotion of a constant physical exercise. 1, 2 No doubt careful attentions must be given to the nutritional condition of obese people, the dietary habits, the somatic build (i.e. distribution of fat mass) and the organic functions linked to formation of the fat mass. All the parameters should be constantly monitored before, during and after a diet treatment. 3, 4, 5     

BLOOD PRESSURE CHANGE WITH AGE IN SALT-SENSITIVE TEENAGERS

Objective To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing.Methods Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years.Results After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teenagers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8±5.2 mmHg, P＜ 0.01; 12.2%± 12.0% vs. 2.5% ±4.4%, P＜ 0.001,respectively). There was a similar trend for diastolic blood pressure (8.4 ± 6.4 mmHg vs. 3.7 ± 6.4 mmHg, P = 0.052; 13.2% ±10.6 % vs. 6.8%± 10.1%, P = 0.053, respectively).Conclusions Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure.     

Relationship between Dysglycemia and Carotid Atherosclerosis in Tibetan Population

People with dysglycemia are at high risk for atherosclerotic diseases. This study aims at investigating the atherosclerotic vascular damage in dysglycemia and its metabolic origin in Tibetan population.     

APPLICATION OF LORNOXICAM TO PATIENT-CONTROLLED ANALGESIA IN PATIENTS UNDERGOING ABDOMINAL SURGERIES

FOR anesthesiologis s ,treatingpostoperativepainhas alwaysbeen a problem.Althoughopioidshave been provedtobe effective,theirsideeffectscouldnotbeignored.With thedevelopmentofscienceand pharmacology,many drugs with aspectsof satisfactoryanalgesicefficacyand couldbe welltoleratedby patientshave been developed.And lornoxicamisone of them, which isa non-steroidalanti-inflammatorydrug (NSAID ), with analgesic, anti-infl-ammatory,andantipyreticproperties.Itseliminationhalf-time(3 to 5 hours) isle…     

CLINICAL SIGNIFICANCE OF SERUM CYTOKINES IL-1β,sIL-2R,IL-6,TNF-α,AND IFN-v IN ACUTE CORONARY SYNDROME

Objectives To explore serum cytokines levels (including IL-1 β, sIL-2R, IL-6, TNF-α, and IFN-v) and their significance in patients with acute coronary syndrome (ACS) and the subsequent follow-ups, with attempt to estimate the role of various serum inflammatory markers in the diagnosis and assessment of ACS.Methods The study population include 40 patients with acute myocardial infarction (AMI), 40 patients with unstable angina pectoris (UAP), and 40 controls. Among the 80 patients, 60 patients attended a follow up 4 months later. Serum inflammatory markers including IL-1 β, sIL-2R, IL-6, TNF-α, and IFN-v were measured by enzyme linked immunosorbent assay.Results Serum IL- 1 β, sIL-2R, IL-6, TNF-α were significantly higher in AMI group or UAP group compared to the control group and became significantly lower 4 months later in the follow-up patients. Serum levels of IFN-v shows no significant difference between AMI group or UAP group and controls, also showing no significant change when measured in follow up patients. There was no correlation between serum creatine kinase-MB isoenzyme levels and serum inflammatory markers either in UAP or AMI group. Furthermore, when divided into two subgroups using Wagner's QRS scoring system in the AMI group, there is no difference of each serum inflammatory marker between ≤ 6 scores group and ＞ 6 scores group.Conclusion Serum levels of certain inflammatory markers may have some diagnostic value for ACS, and can be a useful marker reflecting disease stability.     

Possible Spread of adenovirus type 3 from poultry to humans ：indirect evidence from an outbreak in China

Objective:To explore the epidemiology and etiology for an outbreak of acute respiratory tract infection that occurred in one county of Jiangsu Province, China 2004. Methods: Only cases meeting the case definition were included in the study. We reviewed the medical records of the cases who were admitted to the local hospitals, interviewed cases by a standard questionnaire, and then described the epidemiotogic features and analyzed risk factors by means of a case-control study. We collected pharyngeal swab specimens and sent them to different laboratories for isolation and culture. The laboratory used different detection methods such as DIP, PCR, electron microscope examination and microneutralization assay, to identify and then type the positive specimens. Results:A total of 871 cases were reported during the period from April 18 to July 4,2004. The distribution of onset times presented two peaks, one in late May and another in middle June. The epidemic occurred mainly in the elementary and junior high schools in ten townships of one county, and the mean age of the cases was 12 years (range 7 months to 18 years). The course of the disease was acute, and was characterized by fever accompanied with sore throat and tonsillitis. The WBC count of cases was normal or elevated. The mean duration of illness was 5 days (range 2 to 12 days). No fatalities from illness were reported. A case-control study indicated that the possible risk factors were close contact with a case and/or poultry before onset and sharing of towels among members of the family. The typical CPE was observed through inoculating pharyngeal swab specimens into the HEP-2 cell cultures in different laboratories. An infection of adenovirus type 3 was verified by detecting positive specimens in different methods. Conclusion:This investigation demonstrated that the acute respiratory infection in cases was caused by adenovirus type 3. Cases occurred in over 70 schools in ten townships in 2004, and the route of transmission was possibly close contact with cases or droplet transmission.