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21.
目的探讨奥美拉唑对家兔肾脏IMCD细胞H+/K+交换的影响,以及经洗涤处理是否解除这种影响.方法原代培养家兔肾脏IMCD细胞单层,在100 μmol/L奥美拉唑缓冲液中孵育25 min, 洗涤组则在奥美拉唑缓冲液孵育后,用不含奥美拉唑的缓冲液洗涤IMCD细胞;对照组在不含奥美拉唑的缓冲液孵育25 min;CECF/AM荧光探针法测定各组IMCD细胞H+/K+交换.结果奥美拉唑组的H+/K+交换为(0.016±0.006) dpHi/min(n=8);与对照组的(0.053±0.008) dpHi/min(n=8)相比,相差非常显著(P<0.001);洗涤组的H+/K+交换为(0.016±0.006) dpHi/min(n=6),与对照组(n=6)的(0.052±0.009)dpHi/min相比,相差非常显著(P<0.001).结论 100 mol/L的奥美拉唑对家兔IMCD细胞的H+/K+交换有显著影响,而且洗涤处理不能解除这种抑制.因而,肺心病合并上消化道出血患者使用奥美拉唑时,应综合考虑其利弊.  相似文献   
22.
The purpose of this study was to examine the effects of a 20 km cycle race (TT) on left ventricular (LV) systolic and pulmonary function in 12 endurance cyclists. Spirometry, single-breath diffusion capacity (DLCO) with partitioning of membrane (DM) and capillary blood volume (Vc) components and 2-D echocardiograms were performed before and after the TT. During the TT mean oxygen consumption was 3.79 +/- 0.5 L x min(-1) (83 +/- 5.5% of VO2max) and mean blood lactate was 8.4 +/- 2.4 mM. Following the TT, spirometry values were unchanged, however, DLCO and DM were significantly (P<0.05) reduced. LV systolic function was increased (P<0.05) immediately after exercise, while end-diastolic area was decreased (P<0.05) at all points during recovery. The reduction in DM was correlated with LV systolic function following the TT. This relationship suggests a cardiovascular contribution to pulmonary diffusion impairment following exercise.  相似文献   
23.
The clinical laboratory is regarded as a component of the medical care system extending from physician to laboratory staff and back to physician. From this concept a computer-based system of laboratory information is derived, emphasizing: (1) total laboratory responsibility for the test and its request, and (2) physician-oriented output reports.  相似文献   
24.
A laboratory-developed analog signal processor, driven by a conventional polygraph recorder and associated signal conditioning devices, provides automatic heart beat-by-heart beat preprocessing of various cardiovascular functions for input to a laboratory-type minicomputer. The technique of preprocessing individual functions, integrated with the minicomputer system which includes an A/D converter and teletype as input-output peripherals, provides a low-cost data acquisition and reduction system for the on-line computation and analysis of cardiovascular functions in experimental research applications. Such preprocessing more efficiently uses the minicomputer's memory to handle large amounts of information since the digitized data is in the form of one data sample, per function, per heart beat. Preprocessing analog data provides a low density data format and simplified software programs that are ideally suited for the utilization of a minicomputer in this on-line application.  相似文献   
25.
观察血浆置换、内科治疗对中晚期重型乙型病毒性肝炎生存率的影响,探索中晚期重型肝炎的治疗方法。方法观察在内科治疗基础上给予血浆置换患者的肝功能、并发症及疾病的转归,与同期仅予内科综合治疗的患者相比较,对相应的临床资料进行统计学分析,从而了解两种治疗方法的疗效。结果血浆置换组36例,18例好转、18例死亡,内科治疗组32例,13例好转、19例死亡,两组之间患者生存情况无统计学差异;肝功能指标(ALT、AST、SB、ALB、TC、ChE和凝血酶原时间(PT)也无统计学差异。结论与内科治疗相比较,在其基础上给予血浆置换并不能提高中晚期重型病毒性肝炎生存率;中晚期重型肝炎患者的预后决定于其肝功能衰竭的程度。  相似文献   
26.
In the method of constant stimuli applied to measuring heartbeat detection, subjects judge the simultaneity of heartbeats and exteroceptive comparison stimuli presented at various intervals after the R-wave (0, 100, 200, 300, 400, and 500 ms). Using versions of this procedure, investigators have found that between 20% (Yates, Jones, Marie, & Hogben, 1985) and 54% (Brener, Liu, & Ring, 1993) of subjects can detect heartbeat sensations. Whereas Yates et al. used a single comparison stimulus on each trial and Brener et al. used 10, the present study examined whether this disparity in heartbeat detection performance could be attributed to the number of comparison stimuli presented on each trial. In each of 360 trials, 30 subjects judged the simultaneity of heartbeat sensations and tones following 1, 5, or 10 comparison stimulus presentations. Significantly fewer subjects met the criterion for heartbeat detection with I tone presentation (13%) than with either 5 (43%) or 10 (47%) tone presentations. It is concluded that a single stimulus presentation imposes data limitations that result in underestimation of the accuracy of heartbeat detection. The presentation of at least 5 stimuli in each trial alleviates this limitation.  相似文献   
27.
Caffeine actions on currents induced by calcium-overload in Purkinje fibers   总被引:2,自引:0,他引:2  
The ionic events underlying the changes induced by caffeine in calcium-overloaded Purkinje fibers were studied by means of a voltage-clamp technique. The following results were obtained. In fibers exposed to strophanthidin (5 X 10(-7) M), a depolarizing clamp of suitable magnitude or duration is followed by an oscillatory current (Ios) often superimposed on a decaying inward tail current (the "tail current"). Caffeine (9 mM) abolishes Ios and increases the tail current. Caffeine has similar actions when calcium overload is induced by increasing [Ca]0 or decreasing [Na]0. The magnitude of the tail current is reduced by decreasing [Ca]0. The tail current appears with repolarizations to -40 mV or more negative values as Ios appears in the absence of caffeine. As with Ios the tail current can be triggered twice (during and after a test clamp of suitable characteristics), becomes more inward with repeated clamps and becomes larger with larger or longer conditioning clamps. During the recovery from caffeine exposure, the tail current decreases gradually as Ios returns progressively. It is concluded that both Ios and tail current are caused by calcium overload but are affected in opposite direction by caffeine, apparently because caffeine decreases the calcium overload in the sarcoplasmic reticulum (abolition of Ios) and increases the calcium to be extruded from the sarcoplasm (increase in the tail current).  相似文献   
28.
基于统计参数图的脑功能磁共振成像数据处理方法   总被引:1,自引:0,他引:1  
介绍了基于统计参数图的脑功能磁共振成像数据处理方法。脑功能磁共振成像由于其高的时间、空间分辨率、无创性等特点而得到广泛的应用。使用统计参数图进行脑功能成像的数据处理过程主要分为:原始数据的读取、图像预处理、统计分析和统计推论。图像预处理包括运动伪影的消除、图像标准化、图像空间平滑;统计分析包括广义线性模型的建立;统计推论包括T检验等。重点介绍了各个过程所使用的传统的处理方法和最新的处理方法。  相似文献   
29.
Several indices have been introduced as convenient alternatives to calculation of the physiological shunt fraction (Qs/QT) for the assessment of pulmonary gas exchange. These include: the arterial-alveolar oxygen tension ratio (a/APO2), the arterial oxygen tension-inspired oxygen concentration ratio (PaO2/FIO2), the respiratory index (RI), [A-a)DO2/PaO2) and the alveolar-arterial oxygen tension difference [A-a)Do2). These indices are in use clinically despite the fact that they may not accurately predict gas exchange in situations where FIO2, Qs/QT or arterial-venous oxygen content is changing. The clinical stability of each of these indices, relative to the behaviour of the physiological shunt, was therefore investigated prospectively in ten mechanically ventilated postoperative adults as FIO2 was varied from 0.30 to 1.00. None of the indices studied reliably reflected the behaviour of the physiological shunt. As FIO2 was increased incrementally from 0.30 to 1.00, 42 to 55 per cent of the measured changes in these indices were opposite in direction to the corresponding changes in the physiological shunt. The maximum magnitudes of the opposite changes were substantial; 24 and 22 per cent for the a/APO2 and PaO2/FIO2 ratio respectively, 67 per cent for the RI and 101 per cent for the (A-a)DO2. We conclude that the use of any of these indices for clinical assessment of a patient's gas exchange defect when FIO2 is varying can be substantially misleading.  相似文献   
30.
通过对变温热交换水箱的智能化设计(硬件和软件),实现了循环水温的自动化控制,从而达到对热交换水箱中逆向运动的血液温度按临床需要自动进行温度调节。  相似文献   
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