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91.
Conditions under which amphetamine may facilitate stimulus detection task choice performance in rats were investigated. Rats
(n=15) were trained in a two-choice, light-detection task to three successively more stringent criterion levels of task training
(minimal, intermediate, and extended) and then tested after administration of saline, 0.25, 0.50, and 0.75 mg/kg d-amphetamine (AMP). For each training level, baseline levels of choice accuracy were maintained at approximately 82% by manipulating
the animals’ cue duration. No aspect of performance was enhanced by any dose of AMP after minimal criteria training, and there
was a dose-dependent decrease in the number of trials completed. After the intermediate level of training, the 0.25 mg/kg
dose of AMP reliably increased choice accuracy, there was no reliable change in choice reaction time, and there was a dose-dependent
decrease in the number of trials completed. After the extended training, the 0.25 mg/kg dose of AMP reliably increased choice
response accuracy, the 0.25 and 0.50 mg/kg doses of AMP reliably decreased choice reaction time, and there was no reliable
change in the number of trials completed at any dose of AMP. These results support the contention that psychostimulants can
facilitate the choice performance of rats in stimulus detection tasks if an appropriately low dose is used and the animal’s
behavior is strongly controlled by the stimulus-reinforcement contingencies of the task.
Received: 24 September 1997 / Final version: 9 May 1998 相似文献
92.
M. Antonelli M. L. Moro R. R. D'Errico G. Conti M. Bufi A. Gasparetto 《Intensive care medicine》1996,22(8):735-741
Objective The aim of this study was to identify risk factors and to describe epidemiological patterns for early—(EOB) and late—onset bacteremias (LOB) after trauma.Design A prospective study conducted on 141 consecutive trauma patients.Setting A general intensive care unit (ICU) of a university hospital.Patients All multiple trauma patients admitted to our general intensive care unit (ICU) from December 1990 to May 1992 were prospectively enrolled in the study. The following information was collected for each patient and recorded in a computer database: demography, severity of trauma according to the Abbreviated Injury Scale (AIS), severtity of trauma according to the Glasgow Coma Scale (GCS), presence of pneumothorax, pulmonary contusion, rib fractures, hemothorax, and abdominal trauma, use of mechanical ventilation, and placement of central venous catheters. Bacteremias were defined as EOB when onset occurred within 96 h after trauma, and as LOB when appearing after 96 h from trauma.Results Thirty-seven patients developed bacteremia during their ICU stay (26%): 11 (29.7%) EOB and 26 (70.3%) LOB. Gram-positive cocci were isolated more frequently in EOB than in LOB (x
2=4.1,P=0.04). The risk of EOB was significantly increased by the presence of pulmonary contusion [relative risk (RR) 15.0; confidence interval (CI) 1.99-113.25], pneumonia before the onset of bacteremia (RR 3.56; CI 1.17-10.69), AIS score greater than 32 and an abdominal injury score greater than 9 (RR 3.11; CI 1.02-9.49), while intravascular catheters and mechanical ventilation did not represent risk factors for EOB. LOB had a very different pattern and their risk was significantly increased by exposure to intravascular catheters (RR 4.96; CI 1.23-19.94) and to mechanical ventilation lasting more than 7 days (RR 3.6; CI 1.6-8.1).Conclusions Scoring with the AIS of the abdominal and thoracic trauma at admission to the ICU appears a useful tool for identifying trauma patients at increased risk of EOB. A rigorous policy of catheter placement and maintenance as a means of reducing late bacteremias in trauma patients is essential. 相似文献
93.
Barbara Lowenthal 《Early child development and care》1998,142(1):43-52
Recently, the number of young children who have suffered from the traumas of abuse and neglect has increased. There are negative cognitive, neurological, and psychological effects from this maltreatment which is described in this article. Interventions which can prevent neglect and abuse and further resiliency in the young victims are discussed. As concerned individuals, we need to advocate for preventive and therapeutic efforts which promote resiliency in maltreated children. 相似文献
94.
The local mean and the average difference of four pairs of test locations within the 26° visual field, situated above and below the horizontal nasal meridian, were used to predict the global field indices MD and CLV of the Gl glaucoma program. Out of 539 examinations (194 eyes suspected of having glaucoma), the local indices NDIFF (describing asymmetrical behavior around the nasal horizontal meridian), ND0 (the mean defect in the nasal region), and the global indices MD and CLV were calculated. Seven hundred fifty-five examinations (446 normal eyes) served as a control group. First and second examinations of 146 glaucoma suspect eyes were used to calculate the retest reliability scores for the indices in question. When analyzing the glaucoma suspects, the local index NDIFF, together with the local mean defect, ND0, yielded highly reliable estimates of the global indices MD and CLV, with a retest correlation r = 0.86 for NDIFF, and r = 0.96 for ND0. The covariance of NDIFF with CLV was r = 0.67, while the co-variance of MD with ND0 was r = 0.95.The ranges of the local indices ND0 and NDIFF were each classified into normal range and range of suspected pathology, in analogy to the normal and pathological ranges of the global field indices. Equivalence of the local indices with the corresponding ranges of MD and CLV was investigated and the results are shown. The establishment of local indices may prove to be a powerful tool in early detection of glaucomatous damage. 相似文献
95.
背景 主观认知下降(SCD)是阿尔茨海默病(AD)早期预防的目标阶段,AD与慢性病共病关系密切,但二者间相关性尚不十分明确。目的 探究老年人SCD与慢性病共病的相关性,为AD早期预防和干预提供理论依据。方法 于2021年1月至2022年6月,在广州市城市生活小区和养老机构以便利抽样法抽取≥60岁的老年人612例。采用基础版蒙特利尔认知评估量表(MoCA-B)、临床痴呆量表(CDR)、Hachinski缺血指数量表(HIS)评定客观认知功能水平,通过SCD标准诊断框架和SCD问卷(SCD-Q9)进行分组,将整体客观认知水平无异常、符合SCD标准诊断框架和SCD-Q9≥5分的老年人分入SCD组,将整体客观认知功能无异常和SCD-Q9<5分的老年人为认知无异常(CN)组。采用一般资料问卷收集老年人的社会人口学(性别、年龄、居住地、受教育年限、婚姻状况、退休前职业类型、月收入)和健康相关资料[体质指数、腰围、吸烟习惯、饮酒习惯、饮茶习惯、锻炼频率、午觉习惯及平均时长、睡眠质量、抑郁及焦虑症状、日常生活活动能力(ADL)],其中睡眠质量、抑郁症状、焦虑症状及ADL分别采用匹兹堡睡眠指数量表... 相似文献
96.
ONO—802阴道给药抗早孕50例临床效果观察 总被引:2,自引:0,他引:2
本文报告了停经56天以内的早孕妇女应用ONO-802阴道栓剂抗早孕的临床观察及效果。50例早孕妇女住院观察24小时,阴道投药1枚(1mg/枚),5枚为一疗程。用药后1周、2周、4~6周门诊随访,复查尿HCG、血红蛋白。在第二周随访时判断用药效果。临床结果:总有效率82%,其中完全流产76%,不全流产6%,失败率18%。ONO-802使用方便,副反应轻,是深受广大妇女欢迎的一种非手术终止妊娠的方法。本项试验结果通过与国内PG 联合用药的结果和研究资料对比,ONO-802如果能与丙睾、R2323、天花粉等联合应用,将会提高其抗早孕的有效率。 相似文献
97.
目的评估AO肩锁钢板钩治疗重型肩锁关节脱位的手术疗效.方法回顾性分析两年来27例手术病人的手术治疗和疗效.结果手术方法符合生理结构,手术时间平均30分钟,内固定牢靠.根据Murley和Constant[1]评分,优良率94%.结论 AO肩锁钢板钩治疗重型肩锁关节脱位,手术方法简单,疗效可靠,允许病人术后早期功能锻炼. 相似文献
98.
The Modality Specificity of the Slow Negative Wave 总被引:1,自引:0,他引:1
Event-related potentials were recorded in a simple reaction time task using a 3-sec interval between S1 and S2. The sensory modalities of S1 and S2 were varied across 4 conditions to yield all possible combinations of tones and flashes. A negative component which peaked between 600 and 800 msec after S1 was specific in scalp distribution to the modality of S1 but not S2. It was concluded that this negative component is a response to S1 and not related to processes associated with anticipation of S2. A slow negative shift which peaked at S2 was largest at the vertex in all conditions, suggesting its motor origin. A trend for the latter activity to be more negative in posterior recordings when S2 was visual than auditory leaves open the possibility that the terminal CNV is a combination of motor activities and anticipation of the sensory modality of S2. 相似文献
99.
Currently used nucleic acid amplification tests for the detection of viruses and atypicals in acute respiratory infections 总被引:1,自引:0,他引:1
For the detection of respiratory viruses conventional culture techniques are still considered as the gold standard. However, results are mostly available too late to have an impact on patient management. The latest developments include appropriate DNA- and RNA-based amplification techniques (both NASBA and PCR) for the detection of an extended number of agents responsible for LRTI. Real time amplification, the latest technical progress, produces, within a considerable shorter time, results with a lower risk of false positives. As results can be obtained within the same day, patient management with appropriate therapy or reduction of unnecessary antibiotic therapy in LRTI will be possible. A number of technical aspects of these amplification assays, and their advantages are discussed.The availability and use of these new diagnostic tools in virology has contributed to a better understanding of the role of respiratory viruses in LRTI. The increasing importance of the viral agents, Mycoplasma pneumoniae and Chlamydophila pneumoniae in ARI is illustrated. A great proportion of ARI are caused by viruses, but their relative importance depends on the spectrum of agents covered by the diagnostic techniques and on the populations studied, the geographical location and the season. The discovery of new viruses is ongoing; examples are the hMPV and the increasing number of coronaviruses. Indications for the use of these rapid techniques in different clinical situations are discussed. Depending on the possibilities, the laboratory could optimize its diagnostic strategy by applying a combination of immunofluorescence for the detection of RSV an IFL, and a combination of real-time amplification tests for other respiratory viruses and the atypical agents. When implementing a strategy, a compromise between sensitivity, clinical utility, turn around time and cost will have to be found. 相似文献
100.
目的建立分泌抗EPF(Early pregnancy factor,早孕因子)单克隆抗体的杂交瘤细胞株,纯化单抗并鉴定.方法用本实验室已纯化的早孕和肿瘤源性EPF作为抗原刺激Balb/c小鼠,用免疫后的小鼠脾细胞与同系小鼠骨髓瘤细胞(NS-1)融合,经4次克隆化,获得可稳定分泌抗EPF单克隆抗体的细胞株,注入Balb/c小鼠腹腔制备腹水型单抗,Protein-A亲和层析纯化,SDS电泳和Western-blot等方法分析纯化结果.结果融合后获得一株稳定分泌抗EPF抗体的细胞株(C3D11),克隆化后,获得稳定分泌抗EPF单克隆抗体的细胞株,将增殖后的细胞注射Balb/c小鼠腹腔获得腹水型单抗,以亲和层析法纯化,SDS-PAGE分析显示纯化后去掉了大部分杂蛋白,免疫印迹分析抗体纯度较高,与抗原匹配性良好.结论本研究制备的EPF单克隆抗体为特异性抗EPF抗体. 相似文献