Target and hand position information in the online control of goal-directed arm movements

The present study compared the contribution of visual information of hand and target position to the online control of goal-directed arm movements. Their respective contributions were assessed by examining how human subjects reacted to a change of the position of either their seen hand or the visual target near the onset of the reaching movement. Subjects, seated head-fixed in a dark room, were instructed to look at and reach with a pointer towards visual targets located in the fronto-parallel plane at different distances to the right of the starting position. LEDs mounted on the tip of the pointer were used to provide true or erroneous visual feedback about hand position. In some trials, either the target or the pointer LED that signalled the actual hand position was shifted 4.5 cm to the left or to the right during the ocular saccade towards the target. Because of saccadic suppression, subjects did not perceive these displacements, which occurred near arm movement onset. The results showed that modifications of arm movement amplitude appeared, on average, 150 ms earlier and reached a greater extent (mean difference=2.7 cm) when there was a change of target position than when a change of the seen hand position occurred. These findings highlight the weight of target position information to the online control of arm movements. Visual information relative to hand position may be less contributive because proprioception also provides information about limb position.     

高血压病人血压节律对靶器官影响的探讨

目的 :观察血压昼夜节律变化对靶器官损害程度。方法 :采用动态血压测定 ,通过杓型组 (白昼与夜间血压变化下降百分率 >10 % ,视为血压昼夜节律正常 )与非杓型组 (昼夜血压下降百分率 <10 % ,为血压节律消失 )的血压节律变异比较对心脑肾等靶器官损害。结果 :①非杓型组 2 4小时收缩压 ,2 4小时舒张压 ,夜间平均收缩压 ,夜间平均舒张压 ,血压负荷值均高于杓型组 (P <0 .0 5 )。②血压节律消失的非杓型组病人左室重量和左室重量指数比杓型组显著增大 (P<0 .0 1)。③非杓型组的腔隙性脑梗塞次数和患病率均高于杓型组 (P <0 .0 1)。尿蛋白亦明显高于杓型组 (P <0 .0 1)。结论 :血压昼夜节律消失的高血压病人有较高的血压负荷明显损害心脑肾等靶器官     

Potentially Toxic Element Concentration in Fruits Collected from Markazi Province (Iran): A Probabilistic Health Risk Assessment

ObjectiveThis study was conducted to evaluate the concentration of potentially toxic elements (PTEs) such as arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) in fruit samples collected from Markazi Province, Iran. A probabilistic health risk assessment due to ingestion of PTEs through the consumption of these fruits was also conducted.MethodsThe concentration of PTEs in 90 samples of five types of fruits (n = 3) collected from six geographic regions in Markazi Province was measured. The potential health risk was evaluated using a Monte Carlo simulation model.ResultsA significant difference was observed in the concentration of PTEs between fruits as well as soil and water samples collected from different regions in Markazi Province. The order of PTE concentration in the soil and water samples was as follows: Pb > As > Hg > Cd. Furthermore, the highest level of transfer factor for Cd and Hg correlated with the grape. The estimated daily intake for adults and children was lower than the recommended tolerable daily intake.ConclusionThe population in Markazi Province, Iran, is not at considerable noncarcinogenic or carcinogenic risk due to the ingestion of PTEs through the consumption of the examined fruits.     

2020年深圳市医疗机构放射工作人员职业健康检查目标疾病检出情况分析

目的 了解全市医疗机构放射工作人员的职业健康检查结果的整体情况,为放射防护管理工作提供一定的基础资料。方法 选择2020.1.1—2020.12.31来我院进行职业健康检查的681家医疗机构3 568名放射工作人员的职业健康检查结果进行汇总分析。结果 全市未检出1例疑似职业性放射病,目前全部未见异常的检出率范围为2.17%～2.99%,职业禁忌证的检出率范围为1.44%～2.17%,总复查率在13.00%左右,79.48%以上的人员检出其他疾病或异常;异常率比较高的体检项目主要有眼科、肝胆脾胰B超、肝功能、心电图、血常规、尿常规、血压、双肾B超、肾功能;每级机构放射工作人员的体检结果中眼科的异常率随着工龄的增加而降低,肝胆脾胰B超、血压、双肾B超、肾功能检查结果异常情况总体来讲随着工龄的增加而增高。结论 深圳市各级医疗机构放射工作人员的放射防护总体可能尚可,但不同级别医疗机构、不同工龄工作人员的健康情况也有不同程度的影响,应继续完善工作人员的职业健康监护管理,进一步加强放射防护。     

复发性流产肾虚证小鼠子宫蜕膜组织miRNA表达谱检测及生物信息学分析

目的 探讨微小RNA（microRNA,miRNA）在复发性流产（repeated spontaneous abortion,RSA）肾虚证小鼠子宫蜕膜组织中的表达特征。方法 运用基因芯片技术对所采集的正常对照组和RSA小鼠蜕膜组织进行miRNA检测,运用Genespring软件对miRNA进行筛选及功能分析。应用生物信息学方法分析差异表达的miRNA及其靶向基因在RSA发生、发展中的作用。结果 芯片检测结果显示正常对照组和RSA肾虚证组筛选出差异表达的miRNA共有63条（22条上调、41条下调）,实时荧光定量PCR验证的miRNA的表达情况与miRNA芯片结果一致。京都基因与基因组百科全书通路富集分析及基因本体分析显示,其差异表达的miRNA涉及到PI3K-Akt信号通路、细胞吞噬通路、癌症通路、黏着斑通路、肌动蛋白细胞骨架调控通路、轴突导向信号、MAPK信号通路、PAP-1信号通路等。结论 RSA肾虚证小鼠子宫蜕膜组织中存在差异表达的micro RNA,可能涉及RSA肾虚证的发生、发展。     

Target cells and thymus microenvironment in the pathogenesis of thymic lymphomas in C57BL/Ka mice

In C57BL/Ka mice, the induction of thymic lymphomas either by inoculation of radiation leukemia virus (RadLV) or by a split dose irradiation requires complex cellular events: Target cells are found among the population of thymic subcapsular blast cells, or, alternatively, of marrow or spleen prothymocytes; Progression of target cells to lymphoma growth requires a multi-step process, which occurs only within thymic microenvironment; Target cells are rapidly induced as "preleukemic" cells; After inoculation of RadLV, the initial events occur when target cells are in close association with cells of a specialized component of thymic epithelium, i.e., the so-called "nurse cells"; The leukemogenic agents induce damages to the thymic microenvironment itself; Lymphoma prevention by marrow grafting after irradiation results from mechanisms still unknown which inhibit the progression of "preleukemic" cells to neoplastic growth.     

微量白蛋白尿对老年高血压病患者心脏病变的影响

目的探讨微量白蛋白尿对老年高血压病患者肾小球滤过率(GFR)及心脏病变的影响。方法选择老年高血压病2～3级按有无微量白蛋白尿各64例(观察组、对照组)。观察各组病人GFR、超声心动图、心电图、血肌酐(Cr)、尿素氮(BUN)等。结果观察组的GFR、左室舒张功能均低于对照组(P＜0.01)。观察组左室重量指数(LVMI158.4±8.4)高于对照组(124.1±7.2)(P＜0.01)。结论微量白蛋白尿是老年高血压病患者早期靶器官损害较敏感的指标。