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51.
The purpose of this study was to investigate, during the performance of an object discrimination task, responses of neurons in the monkey hippocampal formation to the sight of several objects that have biological meaning, and compare these responses with those of amygdalar neurons studied previously using the same task. Neuronal activity in the hippocampal formation of conscious monkeys was recorded during performance of a task that led to presentation of familiar rewarding, familiar aversive, or unfamiliar objects. Of 864 neurons recorded in the hippocampal formation and adjacent cortices, 160 (18.5%) responded to the sight of a certain object(s). Responses to the sight of different kinds of objects were analyzed in detail. Nondifferential neurons (n = 73) responded to different objects with no significant difference in response magnitudes, and differential neurons (n = 87) responded to different objects with different response magnitudes. Of the differential neurons, 23 responded more strongly to rewarding objects than to other objects (rewarding-object-dominant neurons), but the magnitude of responses to objects did not necessarily correlates with the order of preferences to the objects as determined from observation of animal behavior. Aversive-object-dominant neurons (n = 13) responded more to aversive objects than to other objects. Unfamiliar-object-dominant neurons (n = 7) responded more to unfamiliar objects than to familiar objects. Selective neurons (n = 10) responded selectively to only one object or one category of objects. Fourteen of the rewarding- or averse-object-dominant neurons were tested in extinction or reversal trials. In 12 of 14 neurons, responses to a rewarding or aversive object did not change, or slightly weakened, in extinction or reversal trials. The results suggest the following. (1) Responses of rewarding- or aversive-object-dominant neurons may be involved in object-reward or object-aversion association. However, responses of many of these neurons might reflect past inputs to reinforcement rather than extant emotional processing. (2) Responses of unfamiliar-object-dominant neurons may be involved in recognition of objects based on their familiar or unfamiliar aspects. These results are further discussed and compared with responsiveness of amygdalar neurons. 相似文献
52.
P. Cortelli P. Parchi E. Sforza M. Contin G. Pierangeli G. Barletta E. Lugaresi 《Clinical autonomic research》1994,4(1-2):57-62
Cardiovascular autonomic function in normotensive awake patients with obstructive sleep apnoea syndrome was studied in 21 normotensive (mean age 48 ± 14 years), drug-free men with obstructive sleep apnoea syndrome. Cardiovascular reflex tests with continuous blood pressure monitoring and biochemical indices were performed the morning after a standard polygraphic sleep recording. A group of 20 agematched (mean age 49 ± 19 years) normal subjects was used as controls. The obstructive sleep apnoea syndrome patients showed higher heart rate and noradrenaline plasma levels (p < 0.05) at rest and a higher blood pressure response to head-up tilt (p < 0.01), suggesting sympathetic overactivity. Respiratory arrhythmia, baroreflex sensitivity index and Valsalva ratio were significantly lower in the obstructive sleep apnoea syndrome group (p < 0.01) whereas the decrease in heart rate induced by the cold face test was significantly higher (p < 0.05) showing a blunting of reflexes dependent on baroreceptor or pulmonary afferents with normal or increased cardiac vagal efferent activity. These abnormalities in autonomic regulation may predispose obstructive sleep apnoea syndrome patients to cardiovascular complications like hypertension and cardiac arrhythmias. 相似文献
53.
Alexander Scriabine 《Cardiovascular therapeutics》2002,20(3):226-232
The XIVth World Congress of Pharmacology took place July 7–12, 2002 in Moscone Convention Center, San Francisco, CA. Over 4,000 scientists, exhibitors and guests attended the Congress. It consisted of 40 symposia, 11 workshops, 18 plenary lectures and ca. 1,400 posters. The Congress was sponsored by the American Society for Pharmacology and Experimental Therapeutics, Inspire Pharmaceuticals and GlaxoSmithKline. The major financial donors were: Eli Lilly and Company, Servier, Johnson & Johnson, Merck, Novartis, Roche, Schering‐Plough, Wyeth and Yamanouchi Foundation. This report covers only presentations and posters on drugs that were attended or viewed by the author. 相似文献
54.
目的:提高X线对肺静脉异常连接的诊断准确性,为手术治疗提供可靠的依据。材料与方法:回顾性分析了11例肺静脉异常连接的X线胸片和病理生理改变,男3例,女8例,年龄8—34岁。从血液动力学变化分析了“8”字征,镰刀综合征等X线典型征象。结果:11例中完全性肺静脉异常连接4例,部分性7例。按部位分心上型6例;心内型4例;心下型1例。肺静脉异常连接或多或少合并房间隔缺损,法鲁氏三联症,以及右肺和肺动脉发育不全。结论:肺静脉异常连接的X线征象十分复杂而多变,因此,术前的仔细观察和精心判别对于手术治疗是非常重要的。 相似文献
55.
Dissociative responses to trauma have been hypothesized to be associated with long-term increases in psychopathology. The purpose of this study was to examine dissociative responses to premilitary, combat-related and postmilitary traumatic events and long-term psychopathology in Vietnam combat veterans with (n = 34) and without (n = 28) posttraumatic stress disorder (PTSD). PTSD patients reported higher levels of dissociative states at the time of combat-related traumatic events than non-PTSD patients. Higher levels of dissociative states persisted in PTSD patients in the form of higher levels of dissociative states in response to postmilitary traumatic events. In addition, dissociative responses to combat trauma were associated with higher long-term general dissociative symptomatology as measured by scores on the Dissociative Experience Scale, as well as increases in the number of flashbacks since the time of the war. These findings are consistent with previous formulations that dissociation in the face of trauma is a marker of long-term psychopathology. 相似文献
56.
报道福建某盐场从事日晒海盐生产人工机体内高镁对心血管系统的影响,通过现场空气、饮水、主良的镁含量测定,并对进入机体途径进行分析,得出空气、卤水接触、饮水为机体镁增高的主要来源。不同对象头发镁含量测定结果显示,以接触卤水、劳动强度大的盐工最高,并随机体内镁含量增高,出现血压偏低、心率减慢、心电图P-R间期延长、QRS波增宽、T波高尖等机体高镁反应,与临床高镁血症相似。 相似文献
57.
McConaghy (1989) argued that the validity of penile circumference responses (PCRs) is at best unestablished and that penile volume responses (PVRs) have been demonstrated to be clearly superior indices of sexual arousal and orientation. In his critique, McConaghy stated that (i) penile erection has been incorrectly identified with sexual arousal, (ii) that PCRs have not been shown to accurately discriminate between divergent patterns of sexual arousal (including paraphilias), (iii) that the methodologies used to compare the two types of transducers are inappropriate, and (iv) that PCRs should not be used for diagnostic and treatment decisions. In this paper, McConaghy's criticisms are reviewed in the context of the existing literature on the subject. Although PCRs and PVRs involve different methodologies, they generally yield results that bear more similarities than differences. Furthermore, there is an extensive and growing literature on the use of PCR measures with various paraphilias. Several of McConaghy's arguments should be considered tentative while others are clearly unsubstantiated. Most of McConaghy's concerns over the validity and uses of PCR measures are empirical questions. Suggestions for future research are offered. 相似文献
58.
Wnt-frizzled信号通路与心血管疾病关系的研究进展 总被引:1,自引:0,他引:1
Many researches have focused on the wnt- frizzled cascade in the recent years, while much work has been done in neoplastic diseases and embryology, the role of the wnt- frizzled signal transduction pathway in cardiovascular diseases has only recently begun to be explored. It plays a very important role in many physiological and pathophysiological processes, such as its transduction pathway, the healing after myocardial infarction, the proliferation, differentiation and orientation of cardiomyocytes, angiogenesis/neovascularization, cardiac hypertrophy and heart failure, the deposition of the extracellular matrix and so on. This article is aimed at its relation with myocardial infarction and the role of this pathway in cardiovascular diseases. 相似文献
59.
目的探讨美托洛尔用于预防老年患者围拔管期心血管反应的方法。方法40例全身麻醉行择期手术的老年患者随机分为A组20例,B组20例,A组围拔管期分次静注美托洛尔0.06~0.1 m g/kg,B组以生理盐水分次静注。观察手术结束时、拔管前5分钟、拔管时、拔管后5、20分钟的心率(HR)、收缩压(SBP)、舒张压(DBP)及心率收缩压乘积(RPP)的变化。结果A组拔管时、拔管后5、20分钟的HR、RPP与手术结束时比较,差异无统计学意义,用药后最慢心率53次/m in,围拔管期血压维持平稳,RPP保持在较低值;B组拔管前5分钟、拔管时、拔管后5分钟的各参数与手术结束时比较明显升高(P<0.01);两组间比较,B组拔管前5分钟、拔管时、拔管后5分钟的HR、SBP、RPP明显高于A组(P<0.01)。结论老年患者小剂量分次静注美托洛尔可以安全地预防围拔管期心血管反应。 相似文献
60.
雌激素及其受体对心血管系统保护作用实验研究进展 总被引:8,自引:0,他引:8
雌激素对心血管系统具有重要的保护作用。雌激素及其受体主要通过调节血管舒张功能、抑制血管平滑肌细胞增殖和迁移以及影响肾素 -血管紧张素等介导这一保护作用。但临床上雌激素替代治疗尚未得到肯定 ,需进一步研究 相似文献