ROBUST GUARANTEED COST CONTROL OF UNCERTAIN NON-LINEAR ROBOTIC SYSTEM USING MIXED MINIMUM TIME AND QUADRATIC PERFORMANCE INDEX

To provide better transient performance in controlling robots, a mixed minimum time and quadratic performance index is used. For known and uncertain revolute robot manipulators a conventional optimal control and a robust guaranteed cost control are proposed respectively. Asymptotic stability is also discussed based on the Lyapunov direct method. The proposed robust control is continuous and requires no knowledge of the uncertain system except for bounding functions.     

NGF prevents the changes induced by monocular deprivation during the critical period in rats

Photic evoked responses were recorded from the striate cortex of Long-Evans hooded intact, monocular visual deprivation (MD) and MD treated with NGF rats. The averaged visual evoked responses (AVER) were obtained from both hemispheres and provided comparison after binocular photic stimuli between the contralateral and the ipsilateral striate cortex with relation to the MD eye. One month of monocular visual deprivation at the critical period of development resulted in marked reduction of the amplitudes of AVER components as compared to the control recordings (P < 0.001). These changes of the AVER could be prevented by NGF infusion to lateral ventricle at the dosage of 2.0–2.4 μg/day for four weeks during the monocular deprivation. In conclusion, the change of AVER amplitudes induced by monocular visual deprivation during the critical period of development can be prevented by NGF infusion to lateral ventricle.     

吡那地尔对高血压心脏结构和功能重构的影响

在等降压剂量下吡那地尔和赖诺普利可使４月龄自发性高血压大鼠的血压下降６．０￣８．０ｋＰａ，并接近同种属正常血压大刀瓣血压水平。     

原发中枢神经系统恶性黑色素瘤的临床特点

目的 分析总结原发中枢神经系统（central nervous system,CNS）恶性黑色素瘤的临床、影像、治疗及预后特点。方法 对首都医科大学三博脑科医院神经外科2011年5月至2021年5月收治并经病理证实的17例原发性CNS恶性黑色素瘤患者的临床资料进行回顾性分析,将其分为4种类型,分析不同类型患者的年龄、影像特点及治疗和预后情况。结果 17例患者中6例为A型（脑表型）,5例为B型（脑池型）,4例为C型（深部孤立型）,2例为D型（椎管及其他型）。表现为颅高压症状者11例、局部神经功能障碍者9例、癫痫者3例。磁共振（magnetic resonance imaging,MRI）平扫出现T1高信号者12例。播散转移13例,其中11例呈线片状。手术切除14例、活检3例,6例术后进行了抗肿瘤治疗。总体中位生存期7个月,综合治疗的患者较单纯手术治疗的患者生存期明显延长［（20.6±7.9)个月vs (3.3±0.9)个月］。各分型间症状、影像及治疗方式均有明显差别。结论 原发CNS恶性黑色素瘤发病率低,多具有较明显的影像特点,临床可分为4种类型。该病需手术联合放射治疗等进行综合治疗,但其恶性程度高,预后差。     

儿童急性白血病伴侵袭性肺部真菌感染的临床特点、真菌分布及影响因素分析

目的 分析儿童急性白血病伴侵袭性肺部真菌感染（IPFI）的临床特点、真菌分布及影响因素。方法 回顾性分析2018年1月—2022年12月安徽省儿童医院82例急性白血病患儿的临床资料,按照是否合并IPFI分为IPFI组（18例）和非IPFI组（64例）。比较两组患儿的一般临床资料;采用多因素一般Logistic回归模型分析儿童急性白血病伴IPFI的危险因素;分析IPFI组患儿的临床特征、真菌菌种分布。结果 18例IPFI患儿均有不同程度的发热,体温>38.5℃占比72.22%,咳嗽咳痰/白色黏痰占比83.33%;18例IPFI患儿中5例表现为结节实变影,7例表现为多发斑片状阴影,8例表现为散在斑片状阴影合并小结节,2例表现多发云雾状毛玻璃样高密度影、间质病变为主。16例获得真菌微生物学证据,血培养2例,肺泡灌洗液涂片1例,血或者肺泡灌洗液NGS检测13例,其中以毛霉菌（31.25%）、曲霉菌（25.00%）、近平滑假丝酵母菌（18.75%）为主;多因素一般Logistic回归分析结果显示,化疗方案含激素■、中性粒细胞缺乏时间≥10 d[■]、抗菌药物使用种类≥2种■均是儿童急性白血...     

心脏螺旋波演化与驱动的计算机实验

我们利用FitzHugh-Nagumo(FHN)类型方程,对二维心肌可激媒质系统螺旋波(Spiral wave,SW)的形成、演化和控制进行了数值模拟,主要有以下研究结果:(1)改变系统的可激性,不会影响SW的激发区宽度,却改变SW的自转周期和旋波核的大小;当可激性达到某一极限值时,SW的自转周期与旋波核的半径趋于无穷大,系统不再出现SW。(2)对SW的均匀近共振小电流驱动,可以引导旋波头(Spiral wave tip,SWT)的漂移运动;当驱动频率接近SW的自转频率时,SWT会沿着圆周漂移,当驱动频率达到共振频率时,SWT会沿着直线漂移。     

The metallothionein-null phenotype is associated with heightened sensitivity to lead toxicity and an inability to form inclusion bodies

Susceptibility to lead toxicity in MT-null mice and cells, lacking the major forms of the metallothionein (MT) gene, was compared to wild-type (WT) mice or cells. Male MT-null and WT mice received lead in the drinking water (0 to 4000 ppm) for 10 to 20 weeks. Lead did not alter body weight in any group. Unlike WT mice, lead-treated MT-null mice showed dose-related nephromegaly. In addition, after lead exposure renal function was significantly diminished in MT-null mice in comparison to WT mice. MT-null mice accumulated less renal lead than WT mice and did not form lead inclusion bodies, which were present in the kidneys of WT mice. In gene array analysis, renal glutathione S-transferases were up-regulated after lead in MT-null mice only. In vitro studies on fibroblast cell lines derived from MT-null and WT mice showed that MT-null cells were much more sensitive to lead cytotoxicity. MT-null cells accumulated less lead and formed no inclusion bodies. The MT-null phenotype seems to preclude lead-induced inclusion body formation and increases lead toxicity at the organ and cellular level despite reducing lead accumulation. This study reveals important roles for MT in chronic lead toxicity, lead accumulation, and inclusion body formation.     

Diagnosis of Kala-Azar by Nested PCR Based on Amplification of the Leishmania Mini-Exon Gene

To diagnose visceral leishmaniasis (kala-azar), we have developed a nested PCR method based on amplification of the mini-exon gene, which is unique and tandomly repeated in the Leishmania genome. Nested PCR was sufficiently sensitive for the detection of DNA in an amount equivalent to a single Leishmania parasite or less. We examined the usefulness of this PCR method using bone marrow aspirates and buffy coat cells collected from kala-azar patients who had or had not received chemotherapy in northwest China. We obtained PCR positivity for all of the parasitologically positive bone marrow samples from the patients. Some ambiguities with the primary PCR results were eliminated by the subsequent nested PCR. The buffy coat samples from 7 of 12 patients with splenomegaly were positive by the nested PCR, although only 2 of them were positive for parasites by culture. However, buffy coat samples from nine children, whose splenomegaly has been reduced and clinically cured by antimony treatment, were all negative. Thus, this nested PCR method represents a new tool for the diagnosis of kala-azar with patient blood samples instead of bone marrow or spleen aspirates obtained by more invasive procedures.     

促甲状腺素释放激素对荷瘤鼠NK和IL－2活性的影响

本文采用中性红和噻唑蓝比色法，观察了促甲状腺素释放激素（ＴＲＨ）对荷瘤小鼠脾细胞ＮＫ活性和ＩＬ－２产生能力的影响，并研究其抑瘤效应及机理。结果表明：ＴＲＨ能够明显抑制小鼠Ｓ１８０腹水瘤移植物的生长，抑瘤率为５４．６％；并能明显提高荷瘤鼠ＮＫ活性和ＩＬ－２产生能力。这一结果提示ＴＲＨ是一种重要的抗肿瘤免疫调节因子。