The Ventricular Depolarization Gradient: Effects of Exercise, Pacing Rate, Epinephrine, and Intrinsic Heart Rate Control on the Right Ventricular Evoked Response

A new pacing technique is described that permits high fidelity recording of the paced ventricular evoked response, including cardiac depolarization. Integration of the paced R wave yields the ventricular depolarization gradient (G_D), which is dependent on activation sequence and the spatial dispersion of activation times. G_Dwas studied in 27 dogs to determine the ejects of treadmill exercise at fixed rate pacing (n = 10), elevation of heart rate in the absence of stress (n = 20), epinephrine at fixed rate (n = 6), and exercise in the presence of normal chronotrophic response (n = 7). Low level exercise (1 mph, 2 min, 15°) at a fixed heart rate produced significant (P < 0.0005) decreases in G_Dthat averaged —-10.8 ± 4.0% (mean ± SD). The rate of change in G_Dwas faster at the onset of exercise than at its cessation (P < 0.0005). Artificial elevation of heart rate at rest produced significant (P < 0.0005) increases in G_D; mean sensitivity of G_Dto rote was 0.27 ± 0.12%/beats/min. Intravenous injection of epinephrine produced significant (P < 0.001) decreases in G_D at two dosage levels (2.5 and 5.0 μg/kg) when evaluated at two baseline pacing rates (150 and 190 beats/min); mean changes in G_Dwere –20.64 ± 0.53% (2.5 μ/kg at 150 beats/min), –25.19 ± 4.20% (5.0 μ/kg at 150 beats/min), –14.18 ± 5.19% (2.5 μ/kg at 190 beats/min), and –24.22 ± 4.94% (5.0 μ/kg at 190 beats/min). Sensitivity of G_Dto epinephrine was dose-dependent (P < 0.01) at each baseline rate, but was independent (P > 0.05) of the rate itself. In the presence of a normal chronotropic response. G_D remained unchanged (P > 0.5) during exercise in spite of significant elevation in heart rate (105.0 to 167.1 beats/min, P < 0.001). These data suggest the presence of an intrinsic negative-feedback control mechanism that maintains G_Dconstant in the healthy heart during homeostatic disturbance. Applications in closed-loop rate adaptive pacing are described.     

Comparison of Buprenorphine and Meloxicam for Postsurgical Analgesia in Rats: Effects on Body Weight, Locomotor Activity, and Hemodynamic Parameters

Buprenorphine is administered to humans and animals for postoperative pain management, although its use is associated with complications. Alternative analgesics, including the nonsteroidal antiinflammatory meloxicam, are available, but information on their postoperative effects is limited. The objective of the present study was to compare buprenorphine (0.03 mg/kg SC twice daily for 3 d) with meloxicam (2 mg/kg SC initial dose followed by 1 mg/kg SC once daily for 2 d) by assessing parameters relating to postsurgical recovery in rats that underwent surgical implantation of radiotelemetric transducers. Rats treated after surgery with buprenorphine showed greater reductions in body weight, food consumption, locomotor activity, and nighttime heart rates than did meloxicam-treated rats. Buprenorphine and meloxicam treatments both had stimulatory effects on mean arterial pressure and daytime heart rate measurements, although effects on nighttime mean arterial pressure were greater in the buprenorphine-treated rats. In summary, the lesser physiologic changes associated with meloxicam, as compared with buprenorphine, suggest that meloxicam offers advantages for use as a postoperative analgesic after laparotomy and radiotelemetric transducer implantation in rats.Abbreviation: HR, heart rate; MAP, mean arterial pressure; WD, Western dietIn collaboration with facility veterinarians, researchers who perform invasive surgical techniques must decide on an appropriate postoperative pain management regimen. From an ethical perspective, minimizing an animal''s suffering should be a primary concern. Moreover, inadequate pain management can compromise a study''s outcome, because activation of the pain cascade can influence physiologic function.¹⁰ In addition, the full pharmacodynamic spectrum of the analgesic drug should be considered, because any of its activities could affect a study''s endpoints. Therefore, appropriate selection of drugs for management of postoperative pain is not a trivial decision.Implantation of radiotelemetric transducers is an invasive but necessary surgical procedure for direct and chronic measurement of hemodynamic parameters in animals. Although noninvasive techniques for blood pressure assessments are available, direct assessment by implantation of arterial catheters is generally considered to yield far superior data,¹³ notwithstanding the cost and surgical expertise required. In rats, implantation of transducers involves an abdominal incision of approximately 4 to 5 cm, visceral manipulation, implantation of a small catheter into the abdominal aorta, suturing the transducer to the inner muscular layer, and finally suturing the abdominal incision.Postoperative analgesia for telemetry implantation, like many other surgeries, often consists of opioid analgesics such as buprenorphine,^9,11,20 a partial µ-opioid receptor agonist. Buprenorphine treatment has been shown to improve overall indications of pain and surgical stress, including postoperative food and water intake, changes in body weight, and ambient locomotor activity, compared with those of untreated controls.²⁰ Nevertheless, there can be unwanted effects associated with buprenorphine use, including rebound hyperalgesia,²³ variability in potency between sexes and strains of rodents,⁷ and issues with food intake (such as anorexia and pica).^6,15 Furthermore, assessment of postoperative pain and recovery are complicated, given that buprenorphine treatment affects growth rate, feeding, and locomotor activity in naive rats;^4,15,19 thus, discriminating between behavioral cues caused by pain compared with those due to buprenorphine treatment per se is problematic. Finally, as an opioid analgesic, buprenorphine use is controlled in most jurisdictions, thereby complicating its availability.Alternative therapeutics for treating postoperative pain include nonsteroidal antiinflammatory drugs such as meloxicam.²¹ Meloxicam acts by inhibiting cyclooxygenases and thus preventing the synthesis of prostaglandin H₂, which is a precursor to mediators that elicit pain and inflammation.²⁴ Although meloxicam is a potential alternative treatment for surgery in rats, knowledge of its effects on recovery and cardiovascular parameters after surgery is incomplete. The objective of this study was to compare the postoperative recovery in rats treated with either buprenorphine or meloxicam for management of pain after surgical implantation of telemetric transducers.     

Effects of Timing and Intensity of Neurorehabilitation on Functional Outcome After Traumatic Brain Injury: A Systematic Review and Meta-Analysis

Objective

To systematically review evidence on the effects of timing and intensity of neurorehabilitation on the functional recovery of patients with moderate to severe traumatic brain injury (TBI) and aggregate the available evidence using meta-analytic methods.

Fear of Pain, Pain Catastrophizing, and Acute Pain Perception: Relative Prediction and Timing of Assessment

Pain-related fear and catastrophizing are important variables of consideration in an individual's pain experience. Methodological limitations of previous studies limit strong conclusions regarding these relationships. In this follow-up study, we examined the relationships between fear of pain, pain catastrophizing, and experimental pain perception. One hundred healthy volunteers completed the Fear of Pain Questionnaire (FPQ-III), Pain Catastrophizing Scale (PCS), and Coping Strategies Questionnaire-Catastrophizing scale (CSQ-CAT) before undergoing the cold pressor test (CPT). The CSQ-CAT and PCS were completed again after the CPT, with participants instructed to complete these measures based on their experience during the procedure. Measures of pain threshold, tolerance, and intensity were collected and served as dependent variables in separate regression models. Sex, pain catastrophizing, and pain-related fear were included as predictor variables. Results of regression analyses indicated that after controlling for sex, pain-related fear was a consistently stronger predictor of pain in comparison to catastrophizing. These results were consistent when separate measures (CSQ-CAT vs PCS) and time points (pretask vs “in vivo”) of catastrophizing were used. These findings largely corroborate those from our previous study and are suggestive of the absolute and relative importance of pain-related fear in the experimental pain experience.

Perspective

Although pain-related fear has received less attention in the experimental literature than pain catastrophizing, results of the current study are consistent with clinical reports highlighting this variable as an important aspect of the experience of pain.     

插管、按压、除颤时机选择对心肺复苏成功率的影响

目的:研究气管插管、胸外按压及心脏电击除颤的时机选择对心肺复苏(CPR)成功率的影响.方法:将178例心脏骤停(CA)病人随机分为时机选择复苏组90例(A组)和常规复苏组88例(B组),比较两组复苏成功率.结果:A组CPR成功率48.9%明显高于B组成功率的19.3%,P<0.05.结论:气管插管、胸外按压及心脏电击除颤需根据CA的不同病因及现场情形进行选择.     

Chemical Heterogeneity of the Living Human Brain: A Proton MR Spectroscopy Study on the Effects of Sex,Age, and Brain Region

Brain chemistry was compared between 19 male and female normal volunteers in the age group 19–31 years, across six brain regions and nine metabolites using in vivo proton magnetic resonance spectroscopy. The relative concentrations of N-acetyl aspartate, choline, glutamate, glutamine, GABA, inositol, glucose, and lactate were measured relative to creatine within 8-cm³ brain voxels. These measurements were performed in six brain regions: thalamus and cingulate, insula, sensorimotor , dorsolateral prefrontal , and orbital frontal cortices in the left hemisphere. Total metabolite concentration was highest in prefrontal regions (28% higher in orbital frontal cortex and 18.7% higher in dorsolateral prefrontal cortex compared with insula and thalamus, P < 10⁻⁷). Subjects 25–31 years of age demonstrated a significant increase in total metabolite concentration in the orbital frontal cortex (35%, P < 10⁻⁷) and sensorimotor cortex (16.7%, P < 10⁻⁵) compared to those 19–20 years of age. These two brain regions also showed gender dependence, with women demonstrating increased metabolite concentrations compared to men (9% increase in sensorimotor cortex, P < 0.002, and 2.1% in orbital frontal cortex). Most other brain regions showed no gender- or age-dependent differences. The results indicate that the living human brain is chemically heterogeneous. The chemical heterogeneity is sex and age dependent and specific for brain region.     

Rate Modulated Pacing Based on Right Ventricular dP/dt: Quantitative Analysis of Chronotropic Response

Right ventricular contractility increases in response to catecholamine stimulation and greater ventricular preload, factors that increase with exercise workload. Thus, the maximum systolic dP/dt may be a potentially useful sensor to control the pacing rate of a permanent pacing system. The present study was designed to test the long-term performance of a permanent pacemaker that modulates pacing rate based on right ventricular dP/dt and to quantitatively analyze the chronotropic response characteristics of this sensor in a group of patients with widely varying structural heart diseases and degrees of hemodynamic impairment. A permanent pacing system incorporating a high fidelity pressure sensor in the lead for measurement of right ventricular dP/dt was implanted in 13 patients with atrial arrhythmias and AV block, including individuals with coronary artery disease, hypertension, severe obstructive pulmonary disease with prior pneumonectomy, atrial septal defect, dilated cardiomyopathy, restrictive cardiomyopathy, and mitral stenosis. Patients underwent paired treadmill exercise testing in the VVI and VVIR pacing modes with measurement of expired gas exchange and quantitative analysis of chronotropic response using the concept of metabolic reserve. The peak right ventricular dP/dt ranged from 238–891 mmHg/sec with a pulse pressure that ranged from 19–41 mmHg. There was a positive correlation between the right ventricular dP/dt and pulse pressure (r = 0.70, P = 0.012). The maximum pacing rate and VO_2max were 72 ± 6 beats/min and 12.61 ± 4.0 cc O₂/kg per minute during VVI pacing and increased to 124 ± 18 beats/min and 15.89 ± 5.9 cc 0₂/kg per minute in the VVIR pacing mode (P < 0.0003 and P < 0.002, respectively). The integrated area under the normalized rate response curve was 96.7 ± 45.7% of expected during exercise and 100.1 ± 43.4% of expected during recovery. One patient demonstrated an anomalous increase in pacing rate in response to a change in posture to the left lateral decubitus position. Thus, the peak positive right ventricular dP/dt is an effective rate control parameter for permanent pacing systems. The chronotropic response was proportional to metabolic workload during treadmill exercise in this study population with widely varying forms of structural heart disease.     

Effects of Extracorporeal Shock Wave Lithotripsy on Single Chamber Rate Response and Dual Chamber Pacemakers

This study evaluated effects of extracorporeal shock wave lithotripsy on four models of Medtronic implantable cardiac pacemakers. In vitro testing consisted of: (1) unsynchronized pacemaker strapped on the patient with extracorporeal shock synchronized to the patient's native heart rate; and (2) pacemakers suspended alone in water 6 inches from the focal point, synchronizing the extracorporeal shock to pacemaker output. Unsynchronized shocks affected each model of pacemaker differently, i.e., single chamber constant rate pacemakers experienced extended periods of inhibition for more than three pacing cycles while activity-triggered rate response pacemakers exhibited rate increases to the upper rate setting. Dual chamber synchronous pacemakers exhibited intermittently a 59% decrease and a 20% increase in ventricular rate due to inhibition and triggering, respectively, from shock oversensing. Synchronized shocks did not alter the rate of single chamber constant rate pacemakers, but did cause the rate to increase to the upper rate setting for activity-triggered rate response pacemakers. The shock was synchronized to the initial atrial output from the dual chamber pacemaker and caused frequent inhibition of the ventricular stimulus when the ventricular-safety-pace (VSP) feature was programmed off. Programming VSP on reduced the incidence of ventricular inhibition resulting in near normal pacemaker operation. There was neither observable damage to pacemaker components nor spurious reprogramming of pacemaker parameters during the tests. Our studies with one manufacturer's pacemakers suggests that lithotripsy shock effects on implantable pacemakers can be tolerated provided: (1) the single chamber pacemaker is programmed to the demand constant rate modality; (2) the dual chamber pacemaker is programmed to VSP on or to the VVI mode; and (3) the pacemaker distance to the focal point is greater than 6 inches.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of Heart Rate and Anesthetic Timing on High‐Resolution Echocardiographic Assessment Under Isoflurane Anesthesia in Mice

Objective. Anesthesia provides sedation and immobility, facilitating echocardiography in mice, but it influences cardiovascular function and therefore outcomes of measurement. This study aimed to determine the effect of the optimal heart rate (HR) and anesthetic timing on echocardiographic reproducibility under isoflurane anesthesia. Methods. Male C57BL/6J mice underwent high‐resolution echocardiography with relative fixed HRs and anesthetic timing. The same experiment was repeated once again after 1 week. Results. Echocardiography was highly reproducible in repeated measurements under low‐HR (350–400 beats per minute [bpm]) and high‐HR (475–525 bpm) conditions except some M‐mode parameters under low‐HR conditions. With similar anesthetic timing, mice with a high HR had decreased preload indices and increased ejection phase and Doppler indices. Inversely, when the HR was similar, the echocardiographic results of mice under short anesthetic timing showed little difference from the ones under long anesthetic timing. Conclusions. This study shows that echocardiographic assessment is greatly reproducible under a high HR. The HR is more important than anesthetic timing for echocardiographic evaluation in mice.     

Music Modulation of Pain Perception and Pain-Related Activity in the Brain,Brain Stem,and Spinal Cord: A Functional Magnetic Resonance Imaging Study

The oldest known method for relieving pain is music, and yet, to date, the underlying neural mechanisms have not been studied. Here, we investigate these neural mechanisms by applying a well-defined painful stimulus while participants listened to their favorite music or to no music. Neural responses in the brain, brain stem, and spinal cord were mapped with functional magnetic resonance imaging spanning the cortex, brain stem, and spinal cord. Subjective pain ratings were observed to be significantly lower when pain was administered with music than without music. The pain stimulus without music elicited neural activity in brain regions that are consistent with previous studies. Brain regions associated with pleasurable music listening included limbic, frontal, and auditory regions, when comparing music to non-music pain conditions. In addition, regions demonstrated activity indicative of descending pain modulation when contrasting the 2 conditions. These regions include the dorsolateral prefrontal cortex, periaqueductal gray matter, rostral ventromedial medulla, and dorsal gray matter of the spinal cord. This is the first imaging study to characterize the neural response of pain and how pain is mitigated by music, and it provides new insights into the neural mechanism of music-induced analgesia within the central nervous system.     

膳食因素对脑老化小鼠皮层和海马乙酰胆碱酯酶活性的影响

目的探讨高脂和限食对脑老化及脑内乙酰胆碱酯酶(AChE)的影响,为合理膳食健脑防衰提供科学依据。方法雄性ICR小鼠60只分为6组,即脑老化模型组、脑老化+高脂膳食组、脑老化+限食组、高脂对照组、限食对照组、普通对照组,每组10只。以D-半乳糖100 mg/kg·d颈背部皮下注射制备脑老化模型。实验干预期共9周。以Morris水迷宫测试小鼠空间记忆和学习能力,羟胺比色法测定脑组织乙酰胆碱酯酶(AChE)活性。结果①水迷宫实验：脑老化组小鼠的逃避潜伏期高于普通对照组(P<0.05),脑老化+高脂膳食组逃避潜伏期与脑老化组无显著性差异(P>0.05),高脂膳食组与普通对照组之间逃避潜伏期亦显著无差异(P>0.05)。脑老化+限食组的逃避潜伏期低于脑老化组(P<0.05),而与普通对照组无显著性差异(P>0.05),限食对照组与普通对照组之间逃避潜伏期无显著性差异(P>0.05)。②AChE活性：脑老化组、脑老化+高脂膳食组和脑老化+限食组小鼠高于普通对照组和限食对照组(P<0.05),限食对照组与普通对照组无显著性差异(P>0.05)。脑老化+高脂膳食组高于脑老化组和其他非模型对照组(P<0.05)。结论高脂膳食可使脑内AChE活性升高,但对小鼠学习记忆能力无明显影响;限食可提高脑老化小鼠学习记忆能力,但对脑内AChE活性无明显影响。     

TCD检测成功率的相关因素系列研究：绝经对TCD探测成功率的影响

本文通过对４１５例绝经期妇女ＴＣＤ探测成功率的观察发现：绝经是影响ＴＣＤ颞窗探测成功率的生理因素之一；ＴＣＤ颞窗测成功率与超声发射功率呈对正相关关系；并提出临功率在ＴＣＤ探测中的实用价值。     

Atrial Fibrillation in the Intact Unanesthetized Dog: Hemodynamic Effects during Rest, Exercise, and Beta-Adrenergic Blockade

The effects of atrial fibrillation were studied in 12 healthy unanesthetized dogs, 9 to 49 days after surgical implantation of transducers for measurement of aortic flow and left ventricular diameter. Atrial fibrillation and pacing at comparable ventricular rates were induced by electrical stimulation of the right atrial appendage, and their effects were compared with observations made during sinus rhythm in each dog. At rest, cardiac output and mean arterial pressure were not significantly different during sinus rhythm, atrial fibrillation, and atrial pacing. After beta-adrenergic blockade with propranolol, cardiac output during fibrillation was significantly less than that during pacing at comparable ventricular rates. Arterial pressure was not detectably altered. During moderately severe treadmill exercise by six dogs, cardiac output fell significantly upon induction of fibrillation. After pentobarbital anesthesia fibrillation caused decrements in cardiac output and arterial pressure that were accentuated after thoracotomy.These observations suggest the existence of compensatory mechanisms that maintain an essentially constant cardiac output when atrial fibrillation is induced in healthy unanesthetized dogs at rest. These mechanisms appear to fail during moderately severe exercise, beta-adrenergic blockade, and pentobarbital anesthesia.     

Pharmacologic and Hemodynamic Influences on the Rate of Isovolumic Left Ventricular Relaxation in the Normal Conscious Dog

We studied the effects of acute pharmacologic and hemodynamic interventions on isovolumic left ventricular relaxation in 19 conscious dogs using micromanometer tip catheters. Isoproterenol (11 studies) augmented peak rate of rise of left ventricular pressure [(+) dP/dt] by 1,275±227 (SE) mm Hg/s (P < 0.001) and dP/dt at an isopressure point of 35 mm Hg during isovolumic relaxation [(−) dP/dt₃₅] by 435±80 mm Hg/s (P < 0.001). Peak (−) dP/dt decreased by 467±89 mm Hg/s (P < 0.002). The time constant, T, derived from the logarithmic fall of pressure during isovolumic relaxation, shortened from 20±2.8 to 14.9±1.8 ms (P < 0.003). Calcium (11 studies) increased peak (+) dP/dt and (−) dP/dt₃₅ (both P < 0.0001); peak (−) dP/dt was unchanged. T shortened from 20.4±1.8 to 17.3±1.5 ms (P < 0.002). Volume (13 studies) did not affect either dP/dt or T. Phenylephrine (13 studies) augmented peak (−) dP/dt, but reduced (−) dP/dt₃₅ (both P < 0.01); T lengthened from 22.1±1.5 to 32.5±1.5 ms (P < 0.01). In 15 studies, rapid atrial pacing increased peak (+) dP/dt and (−) dP/dt₃₅ (both P < 0.01). In the first post-pacing beat, peak (−) dP/dt and (−) dP/dt₃₅ decreased (both P < 0.01), although peak (+) dP/dt increased further. T paralleled values of (−) dP/dt₃₅. In five dogs, beta adrenergic blockade had no significant effect on any variable after calcium, volume, or phenylephrine infusion or during or after atrial pacing when the pre-and post-propranolol states were compared.     

Time Is Brain: Prehospital Emergency Medical Services Response Times for Suspected Stroke and Effects of Prehospital Interventions

ObjectivesTo compare prehospital time for patients with suspected stroke in Florida with the American Stroke Association (ASA) time benchmarks, and to investigate the effects of dispatch notification and stroke assessment scales on prehospital time.Patients and MethodsA retrospective analysis was performed using data from Florida’s Emergency Medical Services Tracking and Reporting System database. All patients with suspected stroke transported to a treatment center from January 1, 2018, through December 31, 2018, were analyzed. Time intervals from 911 call to hospital arrival were evaluated and compared with ASA benchmarks.ResultsIn 2018, 11,577 patients with suspected stroke were transported to a hospital (mean age, 71.5±15.7 years; 51.5% women). The median alarm-to-hospital time was 33.98 minutes (27.8 to 41.4), with a total emergency medical services (EMS) time of 32.30 minutes (26.5 to 39.478). The on-scene time was the largest time interval with a median of 13.28 minutes (10.0 to 17.4). Emergency medical services encounters met the ASA benchmarks for time in 58% to 62% of the EMS encounters in Florida (recommended 90%; P<.001). The total EMS time was reduced when a stroke notification was reported by the dispatch center (32.00 minutes vs 32.62 minutes; P=.006) or when a stroke assessment scale was used by the EMS personnel (31.88 minutes vs 32.96 minutes; P=.005).ConclusionThis study reveals a substantial opportunity for improvement in stroke care in Florida. Two prehospital EMS stroke interventions seem to reduce prehospital time for patients with suspected stroke. Adoption of these interventions might improve the stroke systems of care.     

Hemodynamic Recovery, Atrial Natriuretic Peptide, and Catecholamines During Simulated Ventricular Tachycardia: Effects of Ventriculoatrial Conduction

Ventriculoatrial (VA) sequence and neurohumoral responses may be important modulators of hemodynamic recovery during VT. We studied the effects of VA conduction on blood pressure recovery, and levels of atrial natriuretic peptide (ANP), epinephrine, and norepinephrine during simulated VT. After diagnostic coronary angiography, VT was simulated by rapid right ventricular pacing (150 beats/min, 3 mins) in a consecutive series of patients. Whenever the patients demonstrated VA dissociation during ventricular pacing, they were included in the study. After 10 minutes of recovery, a group of nine patients then underwent an additional VA pacing (150 beats/min, 3 mins, VA delay of 150 msec). Intra-arterial blood pressure was continuously monitored, and plasma ANP and catecholamine levels were measured before, during, and after both pacing protocols. The mean arterial pressures declined rapidly by 26% and 30% after initiation of ventricular and VA pacing, respectively. The blood pressure then gradually recovered, the hemodynamic recovery being better during VA pacing. Plasma ANP and catecholamine levels increased toward the end of both pacing periods. The observed increase in ANP concentration was more prominent during VA pacing than ventricular pacing (P < 0.001), whereas catecholamine levels increased similarly. The results show that during simulated VT hemodynamic recovery is partially dependent on VA sequence. The increases in circulating ANP and Catecholamines occur too slowly to account for the rapid changes in blood pressures observed after initiation of simulated VT. Therefore, other mechanisms, such as reflex stimulation of the sympathoadrenergic nervous system, must be involved, too. ANP release increases when atrial contraction frequency increases, but the exact determinants for this release remain unknown.     

等离子电切与汽化治疗前列腺增生对血液动力学、电解质和血糖的影响

目的：比较等离子双极电切（PKRP）与电汽化术（TUVP）在前列腺手术中对血液动力学及电解质和血糖的影响。方法；前列腺增生（BPH）惠者采用TUVP58例和PKRP70侧，分别对术前、术中20min、40min、60min、80min及术后的血液动力学、电解质和血糖进行比较。结果；与术前值比较，TUvP组Hb和HCt在术中40min、60min下降（P〈O．05），80min下降显著（P〈0．01）；Na^＋在术中60min、80min及术后下降（P〈O．05）；血糖在术中60min、80min及术后升高（P〈0．05）；PKRP组血液动力学、电解质及血糖较术前无显著差异；两组间TUVP组Hb、Hct、Na^＋和血糖较PKRP组有显著差异（P〈O05）。结论：PKRP对患者血液动力学、电解质及血糖的影响明显〈TUVP，是前列腺切除的理想方法。     

The Effects of Blocked Versus Random Presentation and Semantic Relatedness of Stimulus Words on Response to a Modified Stroop Task Among Social Phobics

Previous studies of the modified Stroop Color-Naming Task with social phobics have demonstrated increased latencies for the color-naming of social threat words in comparison to neutral or physical threat words. However, these effects could be partially due to differences in the semantic relatedness of the words in these various categories and/or the blocked format (i.e., all words of one type presented sequentially) in which words have been presented. To examine these issues, color-naming latencies of individuals with social phobia to social threat, semantically related neutral, and unrelated neutral words were examined in both blocked and randomly intermixed formats. Significant differences in color-naming were found for word stimuli presented in the blocked format only. In the blocked format, social phobics were significantly slower to color-name social threat words than related neutral words and significantly slower to color-name related neutral words than unrelated neutral words. Color-naming latencies also increased across trials regardless of word type. There were no effects of word type in the random format. Thus, both presentation format and semantic priming, as well as threat value, may have contributed to color-naming interference for the social threat words. Possible interpretations of our findings along with implications for future Stroop research in persons with social phobia are discussed.