耳穴静态电测量中的瞬变响应

耳穴电参数时变关系实验表明，在测量起始ｔ〈２τ时，因瞬变作用，电位Ｅ和压降Ｕ为瞬态响应，响应函数呈指数关系，特征参数为弛豫时间，τ，τ≈ＲＣ，ｔ〉２τ时，为时变间期。电路分析给出数学描述，并与耳穴和模拟实验结果较相符。     

非牛顿流体流量公式的推导及修正因子的物理定义(以卡森流体、滨汉氏流体为例)

作者依据卡森方程及泊肃叶公式推导出卡森流体的流量公式为：Ｑｃ＝πＲ４ΔＰ８ηｃＬ（１－τｃτ）２。用同样方法导出滨汉氏流体的流量公式为：ＱＢ＝πＲ４ΔＰ８ηＢＬ（１－τＢτ）。对于其它非牛顿流体，只要能建立ηａ与ΔＰ（τ）之间的定量关系，均可代入泊肃叶公式得到该流体的流量公式。卡森流体修正因子（１－τｃτ）２与冈小天流量公式中的Ｆ（ξ）值不同，经实验验证（１－（τｃτ）２值与实验结果吻合，而Ｆ（ξ）值在γ＜２００ｓ－１时与实验结果有较大差距。修正因子有明确的物理意义，它是定量表示屈服值对流量及表观粘度影响程度的物理量。若以τｃ＝０时的流量（Ｑ０）及粘度（ηｃ）为准，则屈服值为τｃ时的流量（Ｑｃ）及ηａ符合下式：Ｑｃ／Ｑ０＝ηｃ／ηａ＝修正因子。该式为实验验证及获得修正因子提供了实验方法及理论依据。作者建议把修正因子作为血液流变学及血液动力学的定量指标。     

阈下条件刺激对心房不应期的影响及对心房起搏节律的抑制作用

给１４例病人作心内电生理检查时，观察阈下条件单个刺激（Ｓｓ）和串刺激（Ｓｔ）对心房不应期和心房起搏节律的作用。初步结果表明：在Ｓ１－Ｓ２间期中加发Ｓｔ，可使心房相对不应期和有效不应期延长；且随Ｓｔ强度的增加，不应期延长量增加。在Ｓ１－Ｓ２间期中加发Ｓｓ，只有３／９例，心房相对不应期延长。另外，Ｓｔ和Ｓｓ可抑制心房起搏节律。     

非牛顿流体流量公式的推导及修正因子的物理定义：以卡森流体,滨汉？…

作者依据卡森方程及泊肃叶公式推导出卡森流体的流量公式为：Ｑｃ＝πＲ＾４△Ｐ／８ηｃＬ（１－根号τｃ／τ）＾２。用同样方法导出滨汉氏流体的流量公式为：ＱＢ＝πＲ＾４△Ｐ／８ηＢＬ（１－τＢ／τ）。对于其它非牛顿流体，只要能建立ηα与△Ｐ（τ）之间的定量关系，均可代入泊肃叶公式得到该流体的流量公式。卡森流体修正因子（１－根号τｃ／τ）＾２与冈小天流量公式中的Ｆ（ξ）值不同，经实验验证（１－根号（ιｃ／     

挫伤性近视治疗前后视觉诱发电位的临床分析

目的：（１）探讨挫伤性近视治疗前后视觉诱发电位的幅值及潜时变化特征；（２）探讨复方樟柳碱治疗的临床效果。方法：采用重庆大学医电仪器公司产ＡＶＳ－１０００视觉电生理仪，对挫伤性近视患采用分组测量。结果：（１）治疗前Ｐ－ＶＥＰ Ｐ１００波幅值降低，潜时延长；（２）配镜矫正后Ｐ１００波潜时仍延长，而振幅幅值升高明显；（３）治疗组治疗后潜时明显缩短；幅值明显升高，对照线与治疗组比较，二行ｔ检验差异非常     

急性实验性门脉高压后兔肠系膜上静脉压力—时间关系

将２０只家兔分为两组。正常组和腹腔神经丛阻滞组，通过阻断门静脉血流的方式造成急性门脉高压，来观察肠系膜上静脉的压力（Ｐ）与时间（ｔ）之间的变化关系，以及压力峰值（Ｐｍ）和到达压力峰值所需时间（Ｔｍ）．结果表明：正常组和腹腔神经丛阻滞组的Ｐ－ｔ关系均为指数函数关系，但两组间常数的比较有显著性差异（Ｐ＜０．０２）；两组Ｐｍ之间的比较没有显著性差异（Ｐ＞０．２），而Ｔｍ之间的比较有显著性差异（Ｐ＜０．０２）。实验证明：腹腔神经丛对门静脉系的血流动力学指标产生重要的影响     

红细胞聚集的电导法研究

依据Ｓ．Ｖｅｌｉｃｈ提出的随机取向红细胞的悬浮液电导方程，提出了测量红细胞聚集动态过程的电导法。在仪器的设计中采用四电极方案克服血液中由于蛋白质等物质吸附在电极表面上对测量结果所造成的影响，采用载波技术克服电极极化所造成的影响，从而提高了测量系统的信噪比、灵敏度和可靠性。根据红细胞悬浮液的电导理论，在实验数据的基础上，建立了描述红细胞聚集的动态过程方程：Ｉ＝Ｉ_ｓ－（Ｉ_ｓ－Ｉ_ｍ）·ｅｘＰ（－（ｔ_ｍ－ｔ）／τ），从而得到了用该法描述红细胞聚集程度指标：聚集指数ＡＩ＝Ｉ_ｓ－Ｉ_ｍ，描述红细胞聚集动态过程的参数：时间常数τ。     

B细胞恶性肿瘤中染色体易位分子机制的研究

在Ｂ细胞恶性肿瘤中已经发现许多染色体异常，其中多数为染色体易位，较常见为ｔ（８；１４）（ｑ２４；ｑ３２）、ｔ（５；１４）（ｑ３ｌ；ｑ３２）、ｔ（ｌｌ；１４）（ｑｌ３：ｑ３２）、ｔ（１４；１８）（ｑ３２；ｑ２１）、ｔ（１４；１９）（ｑ３２；ｑ１３）、ｔ（１；１９）（ｑ２３；ｐｌ３）、ｔ（１７；１９）（ｑ２２；ｌ７１３）、ｔ（４；１１）（ｑ２１；ｑ２３）。在一般情况下，这些染色体易位的一方累及免疫球蛋白（Ｉｇ）基因或Ｅ２Ａ基因，而另外一方累及一个潜在的原癌基因。已知Ｉｇ和Ｅ２Ａ基因都是与Ｂ淋巴细胞密切关联的基因，由于染色体易位，导致这些原癌的基因的活化，可能与Ｂ细胞恶性肿瘤的发生和发展有着密切的关系。     

基于神经元芯片的生物电信号测量方法研究

神经元芯片（Neuronchip）是一种内部集成有3个管线OPU多处理器芯片，它将通讯协议和控制用微处理器有效地集成在一起，实现通信、控制、调度和I／O等功能。以神经元芯片为核心构成的智能测量节点，将这些不同的智能测量节点通过LON总线组成一个新型的生物电信号网络测量系统，由网络系统控制各智能节点可同时测量心电（ECG）、脑电（EEG）、肌电（EMG）、血氧饱和度（BOS）等各种生命特征参数信号。由于小波变换技术具有时、频两域突出信号局部特征的能力，系统中采用不同的母小波函数可完成对不同生物电信号的分析处理，以挖掘出新的有诊断价值的生理信息，取得了较好的效果。文中给出了由神经元芯片构成的智能测量节点的硬件构成、信号测量方法、网络系统的拓扑结构、和实际信号测量波形和小波分析结果。     

46，XX，t（2；6），t（10；21）一例

４６，ＸＸ，ｔ（２；６），ｔ（１０；２１）一例宋黎丽，任国庆，王素桂，沈七英患者女，２７岁，因反复流产及生育畸形儿就诊。患者第１胎人工流产，第２胎孕２个月时自然流产，第３胎孕６个月时早产一女婴为唇裂畸形，第４胎孕３个月时自然流产。患者父母表型正常，无...     

Influence of cyclic mechanical strain and heat of human tendon fibroblasts on HSP-72

Heat shock protein 72 (HSP-72) is a member of a superfamily of different proteins that are synthesized as a cytoprotective response following cellular stress. Mechanical strain is an important component in ligament and tendon healing. Up to the present point of time, the influence of mechanical strain on the expression of HSP-72 is unknown. Tendon fibroblasts from the patellar tendons of nine individuals were isolated and amplified in vitro. First, the effect of 15 or 60 min of heat exposition was studied immunohistochemically and by Western blotting. In a second experiment, the effects of 15 and 60 min of cyclic longitudinal stretching were investigated. Samples were taken after 2, 4 and 8 h. The heat exposition experiments indicate that HSP-72 accumulates in the nucleus and that there is a transient upregulation. This effect is more prominent after 60 min of heat exposure. The same reaction was found after stretching stimulation, however, to a lesser extent. There was a transient up regulation of HSP-72 after short-term stretching and a biphasic increase after 60 min of stretching. Upregulation of HSP-72 by heat and mechanical stress is a response in human fibroblasts which involves a nuclear translocation. The response differs with regard to the time points beyond 2 h after the application of either stress.     

Transducer action of isolated frog muscle spindle evoked by pseudorandom noise stimuli

The dynamic response properties of the isolated frog muscle spindle receptor were investigated by recording the receptor potential evoked by pseudorandom noise (PRN) stimuli. The entire dynamic range of the receptor was determined by measuring the sensory response either at different intensities of the PRN stimulus (sigma = 8-30 microns) around a constant mean length or at the same intensity while varying the mean length from resting length L0 up to L0 + 150 microns. The 3-dB bandwidth of the test signal was 130 Hz. Random stimuli often evoked brief receptor potentials with variable size but characteristic shape. This shape contained a fast depolarization transient of the receptor potential during the stretching phase of the stimulus and a slowly decaying repolarization transient during release of stretch. The depolarization transient rose faster in proportion to the increasing amplitude of the receptor potential, so that larger receptor potentials were more phasic in character than smaller ones. The repolarization transient exhibited two segments of different exponential decay: The first brief repolarization phase lasted for 5 ms; its decline (tau = 2-5 ms) was faster for larger receptor potentials. The second slowly decaying repolarization transient was the same for different receptor potential amplitudes (tau = 47 ms). Consequently, the slow repolarization transients of succeeding receptor potentials displayed temporal summation. Since the amplitude and shape of the receptor potential remained constant during repeated sequences of PRN stimuli, this test stimulus was the most appropriate for the investigation of dynamic response properties under stationary conditions. Long-term stimulation caused a small shift of the mean membrane voltage towards hyperpolarizing values. This finding together with the marked "off effect" after termination of the stimulus indicate the action of an electrogenic pumping mechanism. The dynamic range of the muscle spindle receptor extended from resting length L0 up to L0 + 100 microns. Within this range static prestretches placed a bias upon the transducing site and effectively enhanced the amplitude of the receptor potential. Further prestretch beyond the dynamic region kept the receptor potential constant at its maximum amplitude. The receptor potential amplitude distribution was not symmetrical about the mean but was skewed in favor of depolarization values responding to the stretch trajectories of the PRN stimulus. Variation of the operating point by increasing the static prestretch also shifted the mode of the response distribution towards depolarization.(ABSTRACT TRUNCATED AT 400 WORDS)     

Logistic time constant of isometric relaxation force curve of ferret ventricular papillary muscle: reliable index of lusitropism

We have found that a logistic function fits the left ventricular isovolumic relaxation pressure curve in the canine excised, cross-circulated heart more precisely than a monoexponential function. On this basis, we have proposed a logistic time constant (tau(L)) as a better index of ventricular isovolumic lusitropism than the conventional monoexponential time constant (tau(E)). We hypothesize in the present study that this tau(L) would also be a better index of myocardial isometric lusitropism than the conventional tau(E). We tested this hypothesis by analyzing the isometric relaxation force curve of 114 twitches of eight ferret isolated right ventricular papillary muscles. The muscle length was changed between 82 and 100% L(max) and extracellular Ca(2+) concentrations ([Ca(2+)](o)) between 0.2 and 8 mmol/l. We found that the logistic function always fitted the isometric relaxation force curve much more precisely than the monoexponential function at any muscle length and [Ca(2+)](o) level. We also found that tau(L) was independent of the choice of the end of isometric relaxation but tau(E) was considerably dependent on it as in ventricular relaxation. These results validated our present hypothesis. We conclude that tau(L) is a more reliable, though still empirical, index of lusitropism than conventional tau(E) in the myocardium as in the ventricle.     

纳米刀消融术联合吉西他滨治疗局部进展期胰腺癌的疗效分析

目的探讨纳米刀消融术联合吉西他滨在局部进展期胰腺癌(LAPC)治疗中的安全性及临床疗效。 方法回顾性分析2014年1月至2017年9月间解放军火箭军特色医学中心肝胆外科收治的64例LAPC患者临床资料,其中纳米刀消融联合吉西他滨治疗24例(联合组)和单药吉西他滨化疗40例(对照组)。监测2组患者治疗前与治疗后1、3、5、7、14、30 d的血清淀粉酶、肌酸激酶、乳酸脱氢酶水平,观察治疗前及治疗后7、14、30、60、90 d肿瘤标志物CA19-9水平变化趋势;记录2组治疗中出现的相关性并发症情况;CT影像结合实体瘤评价标准对比治疗前与治疗后90 d的肿瘤体积改变;治疗后通过复诊和电话方式随访16个月,经Kaplan-Meier曲线分析2组患者近期生存状况。对数据采用重复测量方差分析、t检验及χ²检验。 结果治疗前联合组血清淀粉酶[(41.25±20.77) U/L]和对照组[(48.82±18.25) U/L]比较,差异无统计学意义(t＝－1.525,P＝0.132);治疗后1 d,联合组患者血清淀粉酶[(402.71±254.74) U/L]呈现一过性升高,随后逐渐下降,治疗后14 d[(40.03±18.96) U/L]和治疗后30 d[(35.76±16.02) U/L]分别与治疗前相比,差异均无统计学意义(t＝0.213、1.025;P＝0.833、0.311);对照组治疗过程中各监测时间点血清淀粉酶水平比较,差异无统计学意义(F＝5.793,P＝0.058)。联合组与对照组患者治疗过程中,各监测时间点肌酸激酶水平比较,差异均无统计学意义(F＝2.330、1.718, P＝0.065、0.117);乳酸脱氢酶水平比较,差异均无统计学意义(F＝1.240、1.804, P＝0.302、0.137)。联合组治疗后7 d患者肿瘤标志物CA19-9水平出现一过性升高,随后呈下降趋势,治疗后90 d [(114.43±40.61) U/mL]与治疗前[(190.81±100.46) U/mL]相比,差异有统计学意义(t＝3.453,P＝0.002);对照组CA19-9水平于治疗后14 d持续上升,治疗后90 d [(494.57±94.08) U/mL]与治疗前[(212.22±81.34) U/mL]相比,差异有统计学意义(t＝－14.358,P<0.05)。联合组所有患者(100.0%)消融术中均出现术区肌肉震颤,2例(8.3%)患者出现一过性血压升高,治疗后3例(12.5%)患者出现轻度胰腺炎体征,未出现出血、穿孔、胰瘘等严重并发症。对照组中12例(30.0%)患者出现消化道不良反应,9例(22.5%)表现为骨髓抑制症状。联合组治疗后90 d肿瘤体积[(14.17±12.65) cm³]小于对照组[(26.93±17.42) cm³],差异有统计学意义(t＝－3.123,P＝0.003),联合组肿瘤缓解20例(83.3%)明显优于对照组14例(35.0%),差异有统计学意义(χ²＝14.072,P<0.05)。随访表明,联合组平均生存时间为(11.3±3.7)个月,对照组为(7.6±3.4)个月,联合组患者生存情况优于对照组,差异有统计学意义(t＝8.130,P＝0.004)。 结论纳米刀消融术联合吉西他滨化疗可有效控制胰腺肿瘤的局部进展,延长生存期,值得临床推广。     

Rate of action ofAnemonia sulcata toxin II on sodium channels in myelinated nerve fibres

1. The effect of Anemonia sulcata toxin II (ATX II) on single myelinated nerve fibres of the frog, Rana esculenta, was investigated. 2. ATX II promptly and reversibly increased the duration of action potentials; on applying 9.5 micro M the time, t0.5, to reach half of the final effect was 2.6 s. In the presence of 10 mM tetraethylammonium the duration was very sensitive to ATX II and as little as 10 nM could be detected. 3. The underlying mechanism was a diphasic incomplete inactivation of sodium channels which, at 15 degrees C, caused a sizeable INa to persist after 15 ms depolarization (I15ms). 4. On applying 5 micro M (1.25 micro M) ATX II at ca. 15 degrees C, I15ms developed with a sigmoid time course whose t0.5 was 1.5 s (2.6 s) and on washing declined in a near-exponential fashion with tau off = 6.1 s (6.4 s). Washing after a short (1-2s) application led to a transient considerable increase in I15ms followed by a faster decline with tau'off less than tau off. 5. Cooling decreased the rate of action with a Q10 of 1/tau0.5 = 1.9 and of 1/tau off = 2.0 (between 7 and 14 degrees C). ATX I (up to 15 micro M) was ineffective and did not antagonize ATX II. 6. Both rates of diffusional access and reaction seem to contribute to the rate of action. The results suggest a superficial binding site.     

cAMP and Ca2+ act co-operatively on the Cl− conductance of HT29 cells

Previous studies in HT₂₉ cells have revealed that the Cl^– channels induced by cAMP or by increasing cytosolic Ca²⁺, e.g. by addition of ATP, and by hypotonic cell swelling share in common all examined properties, such as ion selectivity and blocker sensitivity. In addition, it was shown that conductances induced by either pathway were not additive. Therefore all three pathways apparently act on the same type of small conductance Cl^– channel. In CFPAC-1 cells the general properties of the Cl^– conductance were identical. However, the cAMP response was absent. In both cell types the Ca²⁺-mediated conductance response was transient. Here we examine the kinetics of the conductance increases induced by neurotensin (NT, 10^–8 mol/l) or ATP (10^–5 mol/l) in HT₂₉ and CFPAC-1 cells using the slow (nystatin) or fast whole cell patch clamp technique, and we ask whether cAMP influences these kinetics. In the continuous presence of NT the conductance response in both cell types was very transient. It collapsed with a time constant () of 39 (30–56 s) in HT₂₉ and of 33 (27–41 s) in CFPAC-1 cells. The ATP response was also transient with a of 49 (42–57 s) in HT₂₉ cells and 102 (77–152 s) in CFPAC-1 cells. Pre-treatment by membrane permeable cAMP (10^–3 mol/l) enhanced the baseline conductance in HT₂₉ but not in CFPAC-1 cells. Furthermore, the ATP- and NT-induced conductance increases became significantly less transient in HT₂₉ but not in CFPAC-1 cells. In the former cells was enhanced significantly to 207 (154–316 s) after ATP and to 1.533 (1004- s) after NT. In CFPAC-1 cells the transient nature of the conductance response persisted. These data indicate that cAMP and Ca²⁺ co-operate in HT₂₉- but not in CFPAC-1-cells. In the former cells the transient conductance response is converted into a more stable response by cAMP. In CFPAC-1 cells the cAMP-mechanism is not functioning. Therefore, all Ca²⁺-mediated conductance responses are only very transient.Supported by DFG Gr 480/10.     

Interpretation of time constant and electrotonic length estimates in multicylinder or branched neuronal structures.

1. We have investigated the theoretical and practical problems associated with the interpretation of time constants and the estimation of electrotonic length with equivalent cylinder formulas for neurons best represented as multiple cylinders or branched structures. Two analytic methods were used to compute the time constants and coefficients of passive voltage transients (and time constants of current transients under voltage clamp). One method, suitable for simple geometries, involves analytic solutions to boundary value problems. The other, suitable for neurons of any geometric complexity, is an algebraic approach based on compartmental models. Neither of these methods requires the simulation of transients. 2. We computed the time constants and coefficients of voltage transients for several hypothetical neurons and also for a spinal motoneuron whose morphology was characterized from serial reconstructions. These time constants and coefficients were used to generate voltage transients. Then exponential peeling, nonlinear regression, and transform methods were applied to these transients to test how well these procedures estimate the underlying time constants and coefficients. 3. For a serially reconstructed motoneuron with 732 compartments, we found that the theoretical and peeled tau 0 values were nearly equal, but the theoretical tau 1 was much larger than the peeled tau 1. The theoretical tau 1 could not be peeled because it was associated with a coefficient, C1, that had a very small value. In fact, there were 156 time constants between 1.0 and 6.0 ms, most of which had very small coefficients; none had a coefficient larger than 2% of the signal. The peeled value of tau 1 (called tau 1 peel) can be viewed as some sort of a weighted average of the time constants having the largest coefficients. 4. We studied simple hypothetical neurons to determine what interpretation could be applied to the multitude of theoretical time constants. We found that after tau 0, there was a group of time constants associated with eigenfunctions that were odd (or approximately odd) functions with respect to the soma. These time constants could be interpreted as "equalizing" time constants along particular paths between different pairs of dendritic terminals in the neuron. After this group of time constants, there was one that we call tau even because it was associated with an eigen-function that was approximately even with respect to the soma. This tau even could be interpreted as an equalizing time constant for charge equalization between proximal membrane (soma and proximal dendrites) and distal membrane (including all distal dendrites).4=     

Changes in light scattering that accompany the action potential in squid giant axons: potential-dependent components

1. To obtain information about structural events that occur in axons, changes in light scattering from squid giant axons were measured during action potentials and voltage-clamp steps.2. The scattering changes were measured at several scattering angles. Because the changes in scattering divided by the resting scattering were between 10(-6) and 10(-5), signal-averaging techniques were used to increase the signal-to-noise ratio.3. The scattering changes during the action potential were different at different angles. Two types were found, one at 10-30 degrees (forward angles) and the other at 60-120 degrees (right angles).4. At forward angles, there was a transient scattering decrease during the action potential. The time course of the change was similar to that of the action potential; this change was thought to be potential-dependent.5. At right angles, there was a transient scattering increase during the action potential followed later by a second, longer-lasting increase. Indirect evidence indicated that neither component could be totally potential-dependent.6. To further analyse these effects, scattering was measured during voltage-clamp steps. The changes seen during hyperpolarizing steps were presumed to be potential-dependent; again two different changes were found, one at forward angles and one at right angles.7. The potential-dependent change at right angles occurred with a time course that could be approximated by a single exponential with a time constant tau = 24 musec. The change at forward angles required two exponentials, tau(1) = 23 musec, tau(2) = 900 musec, to represent its time course.8. The size of both potential-dependent changes was proportional to the square of potential. The change at right angles, but not that at forward angles, was increased in size by the addition of butanol or octanol to the bathing solution.