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It has been established that repeated presentation of a transient target motion stimulus such as a constant-velocity ramp leads to the build up of steady state (SS), anticipatory smooth pursuit eye movements after two or three presentations. Each SS response is then composed of the anticipatory component of nonvisual origin, a visual component associated with the stimulus presentation and another nonvisual component that represents the decay of the response after extinction of the stimulus. Here we investigated the interactions that occur when each motion stimulus was itself a sequence containing more than one ramp component. Ramp components had a velocity of 15 degrees /s or 30 degrees /s to left or right and were separated by gaps of 200 ms duration. In an initial experiment, responses to 2-ramp stimuli were examined and compared with responses to the single-ramp stimuli from which they were constituted. We present evidence that the anticipatory, nonvisual components of the double-ramp response result from the linear summation of the nonvisual components of the responses to the constituent single-ramp components. In a 2nd experiment, we examined responses to a wide variety of 4-ramp sequences and again found evidence that, in the SS, the responses were formed from the linear summation of the constituent single-ramp components. Regression analysis performed on the velocity at onset of each ramp component indicated that this nonvisual part of the response was predictive of the upcoming ramp component. To confirm this, unexpected changes were introduced into single ramp components of the 4-ramp sequence after at least five prior presentations of the sequence had allowed a SS response to be established. Subjects continued to initiate a response to the modified component that was appropriate in velocity and direction for the corresponding part of the previous sequence and inappropriate for the newly modified stimulus. This preprogrammed response persisted unmodified for more than 170 ms after onset of the modified ramp component. In contrast, in the second presentation of the new sequence, the anticipatory component of the response was highly correlated with the SS response of the new sequence, but not with that of the prior sequence, showing that the preprogrammed response had been modified very rapidly. Similar behaviour was observed whichever of the 4-ramp components was modified, indicating that the velocity and direction of the anticipatory response to each component had been preprogrammed. The results suggest that velocity information related to at least four elements of a sequence can be temporarily stored and subsequently released with appropriate temporal order to form an anticipatory response throughout the whole sequence.  相似文献   
3.
要实现人类红细胞深低温保存,必须在冷冻前添加、复温后去除低温保护剂.本研究提出了低温保护剂的新型的透析去除法,与常规的离心洗涤法比较而言,该方法能够快速、有效、安全地去除红细胞内的低温保护剂(甘油).使用该方法冰冻.复温.洗涤后的红细胞计数回收率为(89.17±2.46)%,血红蛋白回收率为(84.93±4.64)%,上清游离血红蛋白的含量为(0.66 ±0.13)g/L,所得冰冻-复温-洗涤后的红细胞悬液的渗透压(残余甘油的含量)为(340.33±20.56)mOsm,均达到了国家对冰冻洗涤红细胞的质量标准要求.  相似文献   
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In 2015, the Indonesian Government initiated ‘Smart Use of Medications Movement’ (‘GeMa CerMat’) which included cadre training to promote responsible self-medication. Evaluation of a pilot training conducted across Indonesia suggested the need to improve those training modules. This study aimed to assess cadre’ knowledge gained following training with newly developed general or specific training modules. Five types of modules were developed and used to train cadres at five Community Health Centres (CHCs) in Surabaya, Indonesia: 1) Sidosermo CHC (general-drugs module), 2) Tenggilis CHC (common cold drugs module), 3) Gunung Anyar CHC (analgesic drugs module), 4) Kalirungkut CHC (anti-diarrhoeal drugs module), and 5) Jagir CHC (indigestion drugs module). Cadres’ knowledge improvements were evaluated using pre-/post-test scores and the difference scores depending on the module being tested. Multifactorial ANOVA explored the effects of the type of module on difference scores. A total of 279 cadres across five CHCs were involved in the training, giving response rates from 65% to 93%. There was an increase in the post-test scores after the training with all modules. However, significant differences were reported only for the specific-drugs module groups (all p < .001). Furthermore, the general module group had the lowest difference score (1.12; 95% CI [−0.45, 2.92]) while the common cold module group had the highest gain (5.02; 95% CI [1.95, 5.17]). Multifactorial ANOVA revealed that there was a significant main effect of the type of modules on difference scores [F (4, 263) = 8.37, p <.001]. In conclusion, this preliminary study indicated that the development of modules for specific minor illnesses could be beneficial in facilitating effective community-based training to promote responsible self-medication in Indonesia. The priority for therapeutic areas chosen for the module should be based on the local needs. Further research is required to confirm the findings in broader community members.  相似文献   
6.
Automated anesthesia recordkeepers have been used to monitor patients during surgery in up to 90% of cases at The Ohio State University. The record-keeping devices are complex and can be difficult to troubleshoot. The 1st-CLASS Fusion Program, an expert system shell-program, has been programmed to allow the resident or nurse anesthetist to solve the two most common types of problems associated with the recordkeeper: printer problems and patient monitor problems. Use of this program allows the resident or nurse anesthetist to troubleshoot the recordkeeper quickly and accurately and promotes in the user a sense of competence and control over the technology.  相似文献   
7.
We conducted molecular analysis of two candidate genes for spinal muscular atrophy (SMA), the survival motor neuron gene (SMN) and the neuronal apoptosis inhibitory protein gene (NAIP), in 16 Japanese patients with SMA and compared the phenotypic features of SMA in these patients with the corresponding genotypes. Exons 7 and/or 8 of SMN were homozygously deleted in 11 SMA type I (Werdnig-Hoffmann disease) patients, two SMA type II patients and one SMA type III patient. Exons 5 and 6 of NAIP were homozygously deleted in six SMA type I patients. No patient had a deletion in NAIP without a deletion in SMN. Mechanical ventilation was required during the first 7 months of life in the SMA type I patients who had a deletion in both SMN and NAIP. Ventilatory support was initiated within 2 years after birth in patients who had a deletion in SMN but not in NAIP. We detected homozygous deletion of exon 5 of NAIP in the unaffected mothers of two SMA type I patients. In these families, the patients exhibited a deletion in both SMN and NAIP. The parents and unaffected siblings of these patients did not have a deletion in SMN. The present findings support the hypothesis that SMN deletion plays an important role in the development of SMA and suggest that combined deletion of both SMN and NAIP may be relevant for determining the disease severity.  相似文献   
8.
目的 揭示核转录因子(PAX2)在肾小管上皮细胞转分化过程中的可能作用。方法 38例病例组肾组织按间质病变程度分为轻、中、重3组,其中轻度病变15例,中度病变11例,重度病变12例;对照组为5例外伤后肾切除组织。采用免疫组化法评定肾组织PAX2的表达率和肾小管上皮细胞转分化率。对肾间质病变轻、中、重3组组内肾小管上皮细胞转分化率、PAX2表达率作方差分析,对PAX2表达量与肾小管上皮细胞转分化率作相关分析。结果 正常对照组肾小管上皮细胞只表达角蛋白(CK),不表达平滑肌肌动蛋白(α-SMA)及PAX2。病例组肾间质病变轻、中、重3组肾小管上皮细胞均不同程度表达α-SMA及PAX2;不同肾间质病变组,肾小管上皮细胞转分化率及PAX2表达量差异均有统计学意义。相关分析表明,PAX2表达量和肾小管上皮细胞转分化率呈正相关(r=0.886,P〈0.05)。结论 PAX2回归表达可能导致肾小管上皮细胞转分化。  相似文献   
9.
目的:观察和解聚散方对单侧输尿管结扎(UUO)大鼠肾组织中α-平滑肌肌动蛋白表达的影响,初步探讨其抗肾间质纤维化的作用机制。方法:采用单侧输尿管结扎致肾间质纤维化大鼠模型,将雄性SD大鼠120只随机分为4组:假手术组,模型组,洛丁新组,和解聚散方组,每组30只,从造模后第2天开始灌胃,洛丁新组为1.0mg/kg/d,和解聚散方组为9.8g/kg/d,假手术组、模型组灌胃生理盐水3ml/只。分别于造模后7,14,21天取梗阻侧肾脏进行HE、Masson染色,观察肾组织病理结构变化;采用免疫组化方法检测肾组织α-平滑肌肌动蛋白(α-SMA)的表达。结果:模型组、洛丁新组、和解聚散方组中α-SMA在术后7天、14天、21天表达均明显高于假手术组,两个治疗组的表达水平明显低于模型组,和解聚散方组14天与洛丁新组14天组比较有显著性差异。结论:和解聚散方可以降低肾组织中α-SMA的表达,这可能是和解聚散方抗肾纤维化的作用机制之一。  相似文献   
10.
The combination of superelastic shape memory alloy fibers and ECC materials can form a new SMA fiber reinforced ECC composite material (SMAF-ECC) with good self-centering performance. In order to study the self-centering performance of the new composite material, 6 groups of pre-notch beam specimens were made for three-point bending cyclic loading tests, and the failure phenomenon, hysteresis curve, self-centering effect and influencing factors of the specimens were analyzed. The research results show that when the SMA fibers are effectively anchored in the ECC matrix, the SMA fibers can exert the superelastic properties to provide the ECC beams with recoverying force, and realize the crack self-closure and deflection self-recovery function for the beams, with the minimum residual crack width and deflection is only 0.9 mm and 1.3 mm respectively. Increasing fiber content can cause a small increase in the self-centering ability of the beams. However, only when the fiber diameter is appropriate, better self-centering effect can be achieved, but the difference caused by fiber diameter in the test was only 5%. SMA Fiber end forms have significant influence on self-centering performance. The knotted end beam can get a more than 70% self-centering ratio, while the straight end beams and bended end beams have no self-centering ability. The research results provide important reference for the research and application of this new self-centering materials and their structures.  相似文献   
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