HTLV-III in saliva of people with AIDS-related complex and healthy homosexual men at risk for AIDS

Peripheral blood leukocytes and saliva from 20 individuals, including four with the acquired immune deficiency syndrome (AIDS), ten with AIDS-related complex (ARC), and six healthy homosexual males at risk for AIDS, were compared as sources of transmissible human T-cell leukemia (lymphotropic) virus type III (HTLV-III), the virus found to be the etiologic agent of AIDS. All of the AIDS and ARC patients and four of the six healthy homosexuals had evidence of prior exposure to HTLV-III as indicated by seropositivity for antibody to HTLV-III structural proteins. Infectious virus was isolated from the peripheral blood of one of the AIDS patients, four of the ARC patients, and two of the healthy homosexual males, consistent with previous reports. HTLV-III was also isolated from the saliva of four of the ARC patients and four of the healthy homosexuals. Virus was also observed by electron microscopy in material prepared by centrifugation of the saliva of one AIDS patient. Although AIDS does not appear to be transmitted by casual contact, the possibility that HTLV-III can be transmitted by saliva should be considered.     

A difference in hypothalamic structure between heterosexual and homosexual men

The anterior hypothalamus of the brain participates in the regulation of male-typical sexual behavior. The volumes of four cell groups in this region [interstitial nuclei of the anterior hypothalamus (INAH) 1, 2, 3, and 4] were measured in postmortem tissue from three subject groups: women, men who were presumed to be heterosexual, and homosexual men. No differences were found between the groups in the volumes of INAH 1, 2, or 4. As has been reported previously, INAH 3 was more than twice as large in the heterosexual men as in the women. It was also, however, more than twice as large in the heterosexual men as in the homosexual men. This finding indicates that INAH is dimorphic with sexual orientation, at least in men, and suggests that sexual orientation has a biological substrate.     

孵化期间鸡胚及蛋内营养物质变化规律

孵化期蛋内营养物质作为鸡胚良好生长发育的前提和基础得到人们越来越多的关注。文章对孵化期间鸡胚和蛋内的钙、磷、蛋白质、脂肪和水分分别在蛋黄、蛋白和胚胎中含量的变化进行了阐述,为胚胎发育的研究奠定基础。     

确定日本壶蚧若虫孵化期方法初探

采用物候法和实时监测法对上海地区寄生于广玉兰的日本壶蚧孵化期进行初步研究.结果表明:物候法和实时监测法都能有效确定日本壶蚧的孵化期,但物候法相关性更好,且准确简便.广玉兰叶芽伸长到3.0 cm时日本壶蚧若虫开始孵化出壳,伸长到9.3 cm左右时,若虫全部孵化出壳,此时广玉兰叶芽开始展叶.可在叶芽长至3.5 cm左右时,及时采取防治措施,控制虫害发生.     

甘肃省苹果树腐烂病菌ITS序列分析及潜育期研究

为了明确甘肃省苹果树腐烂病菌的种类及其优势种的潜育期,通过ITS序列比对和离体枝条接种法对采自甘肃省不同地区的苹果树腐烂病菌进行了ITS序列测定、分析及潜育期研究.结果表明:甘肃省苹果树腐烂病菌有2个种,分别为Valsa mali和Valsa malicola,其中Valsa mali有2个变种,分别为Valsa mali var.mali和Valsa mali var.pyri.甘肃省苹果树腐烂病菌优势种Valsa mali的潜育期随保湿时间增加而缩短,保湿时间为72h时潜育期为74.3h;温度30℃时潜育期最短,为64.3h;潜育期随枝龄的增加而增加,嫩梢的潜育期为46.3h;光暗交替下潜育期最短,为45.3h.     

基于高光谱成像和卷积神经网络的‘库尔勒’香梨黑斑病潜育期诊断研究

黑斑病是‘库尔勒’香梨贮藏期的易染病害之一,在潜育期外观无明显变化,很难直接通过肉眼进行准确识别。本研究结合高光谱成像和卷积神经网络（CNN）,实现了‘库尔勒’香梨黑斑病潜育期的识别。获取健康和不同病害程度香梨样品的高光谱图像,提取感兴趣区域内光谱后,利用不同预处理方法对其进行处理,分别基于常规算法（最小二乘-支持向量机、K最邻近法、随机森林）和CNN建立病害识别模型。结果表明,与常规算法建模结果相比,CNN模型的识别效果最优。当卷积层数为3,全连接层数为3,学习率为0.000 5时,CNN模型的识别效果最佳,对样品的总体识别准确率为99.70%,对潜育期样品的识别准确率为99.76%,分别较常规算法提高了12和14个百分点。该结果证实CNN模型能够显著提高对‘库尔勒’香梨黑斑病潜育期识别的准确率,为‘库尔勒’香梨黑斑病的早期诊断防治提供了1种新的方法。     

基于模型的玉米管理决策支持系统研究

通过对已有玉米生产管理理论和技术研究成果的分析和提炼,运用系统分析理论和数学建模方法,充分挖掘玉米生长和管理指标与品种特性、生态因子及生产水平之间的动态关系和定量算法,分别构建了玉米生长模型和玉米管理知识模型.利用组件技术,在Microsoft Visual C＋＋.NET开发平台上建立了综合性和定量化的基于模型的玉米管理决策支持系统,该系统实现了玉米生长模型与管理知识模型的耦合.利用不同生态点和不同年份的气象、土壤和品种资料及大田比较试验对系统进行了检验,结果表明系统可以有效地进行玉米管理的辅助决策及实时诊断调控.     

A biochemical correlate of the critical period for synaptic modification in the visual cortex

Stimulation of phosphoinositide hydrolysis by excitatory amino acids was studied in synaptoneurosomes of kitten striate cortex at several postnatal ages. Ibotenate and glutamate stimulated phosphoinositide turnover during the second and third postnatal months; N-methyl-D-aspartate and DL-alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) were without effect. The developmental profile of ibotenate-stimulated phosphoinositide turnover parallels the postnatal changes in cortical susceptibility to visual deprivation. The transient increase in ibotenate-stimulated phosphoinositide turnover does not occur in visual cortex of kittens reared in complete darkness.     

基于模型的冬小麦-夏玉米两熟数字化种植设计系统构建

构建基于模型的定量化和数字化种植设计系统。以农业系统学理论和模拟模型为基础,运用知识工程和信息技术原理,总结并提炼黄淮海粮食生产区冬小麦-夏玉米一年两熟制种植模式关键技术,形成了冬小麦和夏玉米生长模拟模型、水分与养分动态平衡模型以及生产管理技术设计动态知识模型,构建了冬小麦-夏玉米两熟数字化种植设计系统。该系统采用面向对象的程序设计方法,在.NET平台上运用C#语言进行开发。该系统具有7大功能模块:文件管理模块、参数管理模块、生长模拟模块、实时管理模块、方案设计模块、专家咨询模块和系统帮助模块。该系统界面友好,易于使用,具有较强的机理性,同时兼顾应用性需求,基本实现了作物生产力与效益品质的相互平衡。     

HTLV-III in the semen and blood of a healthy homosexual man

Human T-lymphotropic virus type III (HTLV-III) is the probable etiologic agent for the acquired immune deficiency syndrome (AIDS). HTLV-III was isolated from semen and blood of a healthy homosexual man whose serum contains antibodies to HTLV-III. The finding of virus in semen supports epidemiologic data that suggest that AIDS can be transmitted sexually. In addition, the demonstration of HTLV-III in the blood and semen of a healthy individual establishes an asymptomatic, virus-positive carrier state which may be important in the dissemination of HTLV-III and, consequently, AIDS.     

山葡萄成龄树夏季修剪试验

为解决山葡萄栽培中夏季修剪费工时问题，我们于1999和2001年对“双优”、“左山二”、“双丰”3个品种的成龄树进行了夏剪试验。结果表明，山葡萄结果枝在花前摘心时留3－5片叶摘心，不留副梢，可减少夏季摘心用工量30％以上，对果实产量及品质无不良影响，其中以留5片叶的表现最好。     

石蛙孵化因子的研究

通过对石蛙蛙卵孵化因子进行研究,发现水中溶氧量、水温和水质是影响蛙卵孵化的主要因子。石蛙孵化要求:溶氧量大于5 m g/L,水温低于28 ℃,水质无污染。     

A critical period for macromolecular synthesis in long-term heterosynaptic facilitation in Aplysia

Both long-term and short-term sensitization of the gill and siphon withdrawal reflex in Aplysia involve facilitation of the monosynaptic connections between the sensory and motor neurons. To analyze the relationship between these two forms of synaptic facilitation at the cellular and molecular level, this monosynaptic sensorimotor component of the gill-withdrawal reflex of Aplysia can be reconstituted in dissociated cell culture. Whereas one brief application of 1 microM serotonin produced short-term facilitation in the sensorimotor connection that lasted minutes, five applications over 1.5 hours resulted in long-term facilitation that lasted more than 24 hours. Inhibitors of protein synthesis or RNA synthesis selectively blocked long-term facilitation, but not short-term facilitation, indicating that long-term facilitation requires the expression of gene products not essential for short-term facilitation. Moreover, the inhibitors only blocked long-term facilitation when given during the serotonin applications; the inhibitors did not block the facilitation when given either before or after serotonin application. These results parallel those for behavioral performance in vertebrates and indicate that the critical time window characteristic of the requirement for macromolecular synthesis in long-term heterosynaptic facilitation is not a property of complex circuitry, but an intrinsic characteristic of specific nerve cells and synaptic connections involved in the long-term storage of information.     

Development of a growth model-based decision support system for crop management

A growth model-based decision support system for crop management (GMDSSCM) was developed, which integrates process-based models of four different crops—wheat, rice, rape and cotton—and realized decision support function, thus facilitating the simulation and application of the crop models for different purposes. The individual models include six sub models for simulating phase development, organ formation, biomass production, yield and quality formation, soil-crop water relations and nutrient (N, P, K) balance. The implemented system can be used for evaluating individual and comprehensive management strategies based on the results of crop growth simulation under various environments and different genotypes. A stand-alone edition (GMDSSCM^A) was established on VC++ and VB platforms by adopting the characteristics of object-oriented and component-based software and with the effective integration and coupling of the growth prediction and decision-making functions. A web-based system (GMDSSCM^W) was then further developed on the.net platform using C# language. These GMDSSCM systems have realized dynamic prediction of crop growth and decision making on cultural management, and thus should be helpful for the construction and application of informational and digital farming system.     

先秦养马业刍议

先秦时期的养马业主要是是一种官方畜牧业,它是国家行政机构的一个重要职能。“国之大事,在祀与戎”,养马业有更多的国家责任和政府行为,其目的是要保障国家政治及军事需求并为贵族提供服务。正是在职有专官、律有明文的情况下,诸多专业畜牧技术都已有了初步发展。在今天看来,先秦时期的养马业是颇有成效的。我国古代的养马业源远流长,可以说自从人类开始驯养动物以来,马就逐渐步入人类的社会政治及经济生活。在氏族社会时代,由于生产力水平低下,动物的驯养还只是作为生活资料的一种补充。到了父系氏族社会末期,由于生产的发展及原始农…