关注心理卫生维护老年健康

本文总结了老年人的心理特点,阐述了老年期的心理卫生问题和常见的老年期精神障碍的发病规律,认为我国老年期心理健康问题既是公共卫生问题,也是突出的社会问题.提出了社会、家庭、个人和心理卫生工作者共同参与的维护老年心理健康的措施.     

DNA序列中弱信号基序查找算法比较与分析

在DNA序列中查找基序是生物信息学中一个重要的计算问题,人们针对这一计算问题提出了多种模型和算法.由于DNA序列数据的复杂性,在其中有许多是比强信号基序更难提取的弱信号基序.而目前植入(ι,d)基序问题(PMP)和扩展植入(ι,d)基序问题(EMP)是较适合模拟弱信号基序查找的问题模型.本文归纳分析了基序查找的基本方法、策略和基序模型,指出了各种策略和模型的优势与不足.在此基础上对现有的基于植入基序查找问题模型的主要弱信号基序查找算法进行了分析和实验评估,为选择计算方法查找弱基序信号提供了参考,并讨论了该方向上尚未解决的问题和发展趋势.     

欧洲近距离放射治疗研讨会内容摘要

1997年5月初我们参加了在瑞典斯德哥尔摩召开的欧洲近距离放射治疗研讨会,重点讨论了近距离与外照射结合治疗的有关问题,包括内、外结合照射生物学特点,物理学的发展和临床经验,并回顾了近距离治疗发展史以及存在的问题和主要成就。大会主席Kovacs首先在开幕式上提出本次会议重点讨论的8个问题:(1)高(HDR)、(LDR)剂量率问题,(2)步进源和直线源问题,(3)个体化优化方案和标准治疗方案问题,(4)施源器的选择问题,(5)外照射剂量的比例问题,(6)内外照射结合的最佳治疗时间问题,(7)应采用那一种外照射技术问题,(8)不同靶组织给予不同剂量问题。现将主要内容从三个方面摘录如下。     

深入开展调查研究 搞好综合利用

当群众性综合利用活动在全厂初步开展起来以后,很多同志提出了这样一个问题:我厂每年需要五万二千多吨原料。而产品只有一万五千多吨,还有三万七千多吨原料究竟是跑到哪里去了,变成什么了?这个问题引起了大家的深思。厂党委和革委会认为这个问题提得好,不解决这个问题,就不能使综合利用工作向深度和广度发展。于是就抓住这个问题,组织人员,对各个产品从工艺着手,调查研究,作了解剖和分     

胶囊内镜检查存在的问题及对策

胶囊内镜的应用虽然很好地解决了小肠疾病诊断的问题,但在临床应用中也给患者和临床医生带来了一些问题,本文重点分析了胶囊内镜检查中存在的问题,并对检查中适应证掌握、检查不全、胶囊滞留等问题提出了相关对策。     

“问题式教学”在解剖学教学中的应用

当前倡导素质教育的核心是以人为本培养学生的创新精神和创新能力,由此确定了要确立科学发展观的课堂教学地位,成为其主要渠道。所谓问题教学模式,是指依据教学内容和要求,由教师创设问题情境,以问题的发现、探究和解决为主线来激发学生的求知欲、创造欲和主体意识,从而培养学生创新能力的一种教学模式。“问题式教学”正适应了当前素质教育的要求,体现了新课程标准的理念,也符合科学发展观教学的基本规律。1“问题式教学”在解剖学教学中开展的意义问题教学是一种发展性教学,在这种教学中学生从事系统的、独立的探索活动,是与其掌握现成的科学结论配合进行的,其方法体系是建立在问题情境的创设和问题的提出与问题的解决基础上。而人体解剖学是历史较为悠久的一门学科,是医学基础课程的基础。     

基于可变连接价格的TCP接入控制研究

本文面向有连接的弹性应用,探讨了基于可变连接价格的TCP接入控制问题.将该问题描述为追求连接阻塞率最小化和活动连接时长最大化的多目标优化问题,分别考察了在连接请求确定到达和随机到达时的连接价格确定问题.提出了在阻塞率不高于某一设定值的情况下,使得单位时间内期望活动连接时长最大化的连接价格调整算法,并给出了基于Socks代理协议的价格协商和接入控制实现方法.     

有关高中生早恋问题的探讨

高中生早恋问题的出现是多种因素导致的,这反映了青春期学生的心理变化,需要运用正确的方式对学生进行青春期教育,积极有效地引导学生。为此,笔者着重分析了高中生早恋问题的心理特征和影响因素,明确学生发生早恋问题的原因,进而提出了有针对性的应对策略,有效应对和控制高中生的早恋问题,促进学生身心健康地发展。     

医学检验技术专业临床实习面临的主要问题及应对策略

目的 探讨医学检验技术专业临床实习面临的主要问题及应对策略。方法 分析医学检验技术专业实习带教过程中存在的问题,建立健全教学管理制度、完善教学质量考评体系;对实习生进行岗前培训和生物安全教育;加强带教老师的队伍建设和规范化管理,运用科学严谨的教学方法,充分调动实习生学习的主观能动性,切实提高实习生的思维能力。结果 加强了实习生临床医学知识的巩固及扩展,培养了实习生临床沟通能力和科研创新思维,提升了实习生提出问题、分析问题和解决问题的能力。结论 通过分析医学检验技术专业临床实习面临的主要问题,找到了应对策略,提高了实习生的综合素质,为医疗机构提供了高素质的医学检验技术专业人才。     

中药颗粒剂包装过程中常见质量问题和解决方法

目的颗粒剂包装过程由于种种原因造成成品质量不合格,为解决颗粒剂包装过程中影响成品质量问题,从两个方面分析影响因素和解决方法。方法采用经验总结与问题剖析法介绍在颗粒剂包装过程中影响颗粒剂质量问题的因素和解决方法。结果有效解决装量差异和外观不合格问题,分析了产生原因并找到了解决办法,提高了一次包装合格率。结论发现并解决中药颗粒剂包装过程中的问题,可提高产品质量,提高一次包装合格率。     

Glucosidase and fucosidase inhibitors and Advances in nucleosides and nucleotides.

The American Chemical Society Symposium "Glucosidase and fucosidase inhibitors" took place on 1 April 1998 and was organized by Professors Zbigniew J Witczak (UConn, School of Pharmacy, CT, USA), Kuniaki Tatsuta (Waseda University, Tokyo, Japan) and Waldemar Priebe, MD (Anderson Cancer Center, University of Texas, USA). Professor Witczak provided introductory remarks including the status of existing glucosidase inhibitors, and chaired the morning session, which consisted of six lectures. The symposium was well received, and was particularly attractive for those interested in networking, as attendance was about sixty. In addition, some participants and attendees presented posters on the subject during the regular poster session organized by the Division of Carbohydrate Chemistry.     

Degraded and undegraded carrageenans and experimental gastric and duodenal ulceration

The prevention of histamine-induced gastric and duodenal ulceration in the guinea-pig has been examined using a series of undegraded and degraded carrageenans. Undegraded carrageenans were active at lower doses than degraded carrageenans. The high viscosity of the undegraded carrageenans in solution prevented their use in larger doses. Degradation of carrageenan without serious loss of sulphate, gives a product which allows the dose to be increased to an extent that its effect more than offsets the slight loss in activity caused by the degradation. No single feature of carrageenan structure can be related to anti-ulcer activity although degradation, and hence reduction of molecular size, generally reduces activity. Sulphate contents over 30% have little apparent effect on activity; κ-carrageenans were not consistently different in anti-ulcer activity from Λ-carrageenans. This contrasts with the antipeptic activity of carrageenans where κ-carrageenans are less active than their Λ-counter-parts. As with antipeptic activity, the degree of anti-ulcer activity is probably determined by a combination of structural features which includes molecular size and polyanionic properties.     

Excretion and biotransformation of alfentanil and sufentanil in rats and dogs

The excretion and biotransformation of alfentanil (ALF) and sufentanil (SUF), two recent analogues of the synthetic opioid fentanyl, were studied after single iv administration of the tritium-labeled drugs in male rats and dogs. The drugs were almost completely metabolized in the two species, which resulted in a large number of metabolites. The excretion of the metabolites was rapid and exceeded 95% within 4 days, except for that of ALF metabolites in dogs (about 85%). For ALF, excretion of the radioactivity with the urine (73% in rats, about 76% in dogs) exceeded that with the feces. For SUF, excretion of the radioactivity with the urine amounted to 38 and 60% and that with the feces to 62 and 40%, in rats and dogs, respectively. Bile-cannulated rats excreted 68% with the bile within 24 hr after SUF dosing, and about 22% of this biliary radioactivity was subjected to enterohepatic circulation. After an ALF dose, the biliary excretion amounted to 24%, and the enterohepatic circulation was minimal. The main metabolic pathways of the two drugs were the oxidative N-dealkylation at the piperidine nitrogen and at the amide nitrogen, oxidative O-demethylation, aromatic hydroxylation, and the formation of ether glucuronides. N-[4-(Hydroxymethyl)-4-piperidinyl]-N-phenylpropanamide (M6) was the main metabolite of both ALF and SUF in rats. In dogs, the glucuronide of N-(4-hydroxyphenyl)propanamide (M5) was the main metabolite of ALF. After SUF dosing in dogs, N-[4-(methoxymethyl)-4-piperidinyl]-N-phenylpropanamide was more abundant than M5.     

Synthesis and antiradical and antioxidant activity of cycvalon and its analogs

A new approach to the activation of components of the condensation of aromatic aldehydes with cyclohexanone, functioning as a receptor for the CH-acid component, is demonstrated. The condensation was performed in the presence of excess phosphorus oxychloride with heating and formed the corresponding 2,6-dibenzylidenecyclohexanone derivatives at high yield. The antiradical and antioxidant activities of the resulting compounds were assessed and cycvalon was found to have the greatest activity. The reference compound (dibunol) did not quench free radicals and had less antioxidant activity than cycvalon. __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 8, pp. 7–10, August, 2007.     

Dietary vitamin E and selenium and toxicity of nitrite and nitrate

Nitrites and nitrates are important antimicrobial and flavoring/coloring agents in meat and fish products. However, nitrites and nitrates may cause methemoglobinemia and other illness, and may react with certain amines to form carcinogenic nitrosamines. The nutritional status of vitamin E and selenium has long been associated with nitrite and nitrate toxicity, although the mechanism involved is not yet clear. Information available recently shows that nitrites and nitrates are both oxidation products and ready sources of nitric oxide (NO*), that NO* reacts rapidly with superoxide to form highly reactive peroxynitrite (ONOO-), and that vitamin E may mediate the generation and availability of superoxide and NO*. Increased formation of ONOO- resulting from nitrite treatment and low intake of vitamin E and selenium may thus be the critical event leading to tissue damage and animal mortality observed previously. The protection against the adverse effects of nitrites/nitrates by vitamin E is attributed to its ability to reduce ONOO- formation, while selenium exerts its protective effects via seleno-enzymes/compounds, which reduce ONOO- formed.     

Antiinfective and encrustation-inhibiting materials--myth and facts

Catheters, urethral and ureteral stents and other urological implants are frequently affected by encrustration and infection due to their permanent contact with urine. Indwelling urinary catheters provide a haven for microorganisms and thus require extensive monitoring. Several surface modification techniques have been proposed to improve the performance of devices including the immobilization of biomolecules, the incorporation of hydrophilic grafts to reduce protein adsorption, the creation of hydrophobic surfaces, the creation of microdomains to regulate cellular and protein adhesion, new polymers and antimicrobial coatings. Physico-chemical explanation to elucidate the mechanism of such encrustation or infection inhibiting materials is still not available. Our series of experiments showed a marked decrease of silver-activity in biological fluids which corresponds with the controversial clinical results obtained with silver coated urinary catheters. Rifampicin/minocycline coated catheters had very low activity against Gram-negative rods, enterococci and Candida spp., the main causing organisms of urinary catheter infection. Surface engineered materials and antimicrobial drug delivery systems will be the next generation of sophisticated urinary catheters and stents, if both efficacy as well as efficiency has been proved clinically.     

Melanocortins and their receptors and antagonists

The melanocortins are a group of small protein hormones derived by post-translational cleavage of the proopiomelanocortin (POMC) gene product. The known melanocortin hormones include alpha-melanocyte stimulating hormone (MSH), beta-MSH, gamma-MSH and adrenocorticotropic hormone (ACTH). Five melanocortin receptors (MCIR through to MC5R) have been identified and most of these show tissue-specific expression patterns, as well as different binding affinities for each of the melanocortin hormones. The central melanocortin system consists of alpha-MSH, agouti-related protein (AGRP), MC3R and MC4R. AGRP and alpha-MSH are believed to be the natural antagonist and agonist respectively of MC3R and MC4R. This central melanocortin system is thought to play a fundamental role in the control of feeding and body weight. Knock-out mice models and genetic studies have pointed to the importance of the melanocortins in complex human pathways such as pigmentation, lipolysis, food intake, thermogenesis, sexual behaviour, memory and inflammatory response. Recently the melanocortins and their receptors have been the target for drug-based treatment of human physiological processes. MC3R and MC4R are likely targets for controlling body weight; MCIR may be used in the treatment of inflammation and MC2R for the treatment of glucocortical deficiency. A role for MCSR still remains unclear, but the evidence suggests an exocrine gland function.     

Cellular and multicellular form and function

Engineering artificial tissue constructs requires the appropriate spatial arrangement of cells within scaffolds. The introduction of microengineering tools to the biological community has provided a valuable set of techniques to manipulate the cellular environment, and to examine how cell structure affects cellular function. Using micropatterning techniques, investigators have found that the geometric presentation of cell-matrix adhesions are important regulators of various cell behaviors including cell growth, proliferation, differentiation, polarity and migration. Furthermore, the presence of neighboring cells in multicellular aggregates has a significant impact on the proliferative and differentiated state of cells. Using microengineering tools, it will now be possible to manipulate the various environmental factors for practical applications such as engineering tissue constructs with greater control over the physical structure and spatial arrangement of cells within their surrounding microenvironment.