810nm弱激光照射对大鼠急性脊髓损伤后巨噬细胞极化的作用研究

本研究构建急性大鼠脊髓夹伤模型,并将大鼠随机分为单纯脊髓损伤对照组及脊髓损伤联合弱激光照射组。照射组应用810 nm波长,150 m W照射功率,照射光斑0.3 cm^2的弱激光对脊髓损伤区进行经皮照射,连续照射3天,7天或14天。应用免疫荧光、免疫印迹实验方法,测定脊髓损伤区巨噬细胞及小胶质细胞的极化表达。应用酶联免疫吸附法测定脊髓损伤区白细胞介素4的表达情况。应用坚牢蓝髓鞘染色测定两组损伤脊髓中髓鞘保留的差异。采用BBB评分对两组大鼠后肢运动功能的恢复进行评估。结果表明,810 nm弱激光对脊髓损伤区连续照射3天,7天后,可显著减少M1型巨噬细胞及其标志物诱导型一氧化氮合酶的表达,在7天时间增加M2型巨噬细胞及其标志物精氨酸酶1的表达。弱激光照射组白细胞介素4的表达明显增加。损伤后14天,弱激光照射组脊髓损伤区髓鞘保留面积比值明显提高。损伤后7天及14天时,弱激光照射组大鼠的BBB评分明显升高。该实验结果表明,810 nm弱激光经皮照射,可增加大鼠急性脊髓损伤区M2型巨噬细胞及小胶质细胞的表达,并减少脊髓损伤后的髓鞘脱失,促进脊髓损伤大鼠运动功能的恢复。     

激光治疗急性踝关损伤40例临床疗效观察

采用SUNDOM-300I型半导体激光（波长810nm,终端输出功率0mW-500mW,连续可调,光速直径5mm）,治疗急性踝关节损伤40例,平均治疗次数为4次,治愈率72.5％,有效率27.5％,示发现明显毒副作用。结果显示激光在治疗软组织疼痛的早期有较好的疗效。     

大鼠脊髓损伤的弱激光治疗参数选择

弱激光在周围神经损伤治疗中取得了理想效果,但在脊髓损伤修复方面的研究很少.本实验应用Allen＇s造模法构建大鼠急性脊髓损伤模型,通过测量穿透功率及组织温度变化筛选出用于脊髓损伤治疗的弱激光照射参数,照射组按照筛选出的参数连续治疗14 d,于术后1、3、7、14、21 d应用BBB评分法评价大鼠后肢运动功能的恢复情况,苏木精-伊红染色（HE染色）观察脊髓病理变化并测量空洞面积.结果显示应用筛选出的照射参数（810 nm、光斑面积0.2 cm2、500 mW/cm2、510 J/cm2）连续照射14 d,术后21 d照射组的运动功能评分显著高于未照射组（P＜0.05）,术后7、14、21d照射组脊髓空洞面积显著小于未照射组（P＜0.05）.结果表明810 nm、光斑面积0.2 cm2、500 mW/cm2、510 J/cm2的弱激光照射能促进急性脊髓损伤大鼠后期运动功能的恢复.     

水稻叶色突变体叶绿体发育规律研究

从温敏核不育系水稻'810S'中筛选出一个生长发育正常的淡黄绿叶色自然突变株'标810S',其叶绿素含量约为'810S'的50%,光合速率比野生型高.以'810S'为对照,对'标810S'进行叶片形态、叶肉细胞和叶绿体超微结构以及叶绿体蛋白研究.结果显示,'标810S'的叶长、宽和面积与'810S'相似;叶肉细胞和叶绿体发育稍迟缓,片层结构减少;叶绿体蛋白约为对照的55%,并初步鉴定出与光合作用相关的差异蛋白点13个,其中4个缺失蛋白,包括1个RuBP大亚基缺失.推测该水稻突变体叶色变浅与叶绿体基粒片层减少有关.     

水稻淡黄绿叶色突变体的光氧化特性研究

为了解水稻淡黄绿叶色突变体‘标810S’的光保护机制,在自然强光条件下对突变体‘标810S’及其野生型‘810S’连体剑叶经5mmol/L甲基紫精(MV)处理后的光氧化特性进行了比较研究。结果表明,在MV处理条件下,突变体‘标810S’剑叶净光合速率(Pn)、PSⅡ最大光化学量子产量(Fv/Fm)、PSⅡ实际光化学量子产量(ФPSⅡ)和光化学淬灭(qP)下降幅度明显低于野生型‘810S’,而非光化学淬灭(qN)上升幅度及PSⅠ和PSⅡ活性则明显高于‘810S’;同时,‘标810S’剑叶抗坏血酸(AsA)、还原型谷光甘肽(GSH)含量以及超氧物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)、抗坏血酸过氧化物酶(APX)、谷胱甘肽还原酶(GR)等抗氧化酶活性均明显高于‘810S’,而超氧阴离子(O-·2)产生速率、膜脂过氧化物丙二醛(MDA)含量则明显低于‘810S’。研究认为,在光氧化处理下淡黄绿叶色突变体‘标810S’是通过增加热耗散、提高抗氧化物质含量和保护酶活性、减少超氧阴离子和丙二醛的积累来维持较高的光系统活性和光合能力,从而表现出耐光抑制(光氧化)的生理特性。     

中药加光疗治疗白癜风临床观察

比较单纯中药和中药结合低强度窄波中波紫外光(low intensity narrow-band ultraviolet B,LUVB)和低强度810 nm半导体激光(low intensity 810 nm diode laser irradiation,LIL)对白癜风的临床疗效。从2008年4月到2010年4月的两年间,93例白癜风患者随机分为治疗组49例和对照组44例,分别采用中药结合LUVB与LIL和单纯中药治疗12周。治疗组痊愈35例(71.4%),显效8例(16.3%),有效4例(8.2%),无效2例(4.1%),总有效率达到了95.9%。对照组痊愈10例(22.7%),显效15例(34.1%),有效4例(9.1%),无效15例(34.1%),总有效率达到了65.9%。结果表明,中药结合LUVB和LIL这种新的治疗方案对白癜风的治疗优于单纯中药治疗,具有相对疗程短,复色快,疗效好,治愈率高等特点,适宜基层医院推广应用。     

采用不同的光传输模型比较研究结肠的散射和吸收特性:离体结肠肿瘤的光学诊断

测定和比较研究了离体的正常的和腺癌的人结肠粘膜/粘膜下层以及正常的和腺癌的人结肠肌层/浆膜组织对630 nm,680 nm,720 nm,780 nm,810 nm,850 nm和890 nm波长的钛宝石激光的散射和吸收系数。采用双积分球测量系统测量组织样品对七个不同波长的激光的准直透射、漫反射和漫透射,从实验所测结果以及分别采用反向倍增法和反演蒙特卡罗技术这两个光学模型计算出组织的散射和吸收系数。研究结果表明,无论是用反向倍增法还是用反演蒙特卡罗法,每一种类型的正常的和腺癌的人结肠组织对同一波长的激光的吸收系数和散射系数有显著性的差异(P<0.01),正常的和腺癌的结肠组织的散射和吸收系数有大的差异,这些结果提示每种类型的正常和腺癌的结肠组织的组份和结构之间有大的差异。四种类型的结肠组织对七个不同波长的激光的散射系数较其吸收系数至少要大三个数量级,而四种类型的结肠组织对七个不同波长的激光的散射系数有相同的数量级。     

转Bt基因玉米对甜菜夜蛾幼虫存活和发育的影响

在室内测定了2种转Cry1Ab基因的Bt玉米MON810和Bt11不同组织对甜菜夜蛾 Spodoptera exigua （Hübner）初孵幼虫以及心叶对4龄幼虫存活和发育的影响,在田间比较了甜菜夜蛾幼虫取食Bt 和非Bt玉米雌穗的存活和为害情况。结果表明,转Cry1Ab基因的Bt玉米的不同组织对甜菜夜蛾初孵幼虫都具有明显的杀虫活性,取食Bt玉米心叶、苞叶、籽粒时甜菜夜蛾均在幼虫期死亡; 取食MON810和Bt11雄穗的初孵幼虫化蛹率分别为5.2%和2.1%,羽化率为2.1%和1.0%;取食MON810和Bt11花丝的初孵幼虫化蛹率分别为1.0%和2.1%,但不能羽化。4龄幼虫取食MON810玉米心叶的化蛹率与对照差异不显著,而取食Bt11的化蛹率与对照差异显著; 取食两种Bt玉米心叶的４龄幼虫化蛹后的雌、雄蛹重和羽化率与对照组差异显著,但蛹期和平均单雌产卵量差异不显著,虽然对照组羽化的成虫平均产卵量高于Bt玉米组。田间接种初孵幼虫10 天后的调查结果表明,在MON810和Bt11玉米花丝上幼虫存活率分别为1.3%和0.3%, 而对照组分别为12.9%和16.2%;MON810和Bt11玉米雌穗被害率分别为18.3%和5.0%,而对照组分别为93.3%和95.0%,均显著低于对照组。     

家蚕微孢子虫感染对家蚕海龟蛋白(Bmtutl)基因表达水平的影响

【目的】本研究旨在阐明家蚕微孢子虫Nosema bombycis感染不同时间对家蚕Bombyx mori幼虫不同组织中家蚕海龟蛋白(Bombyx Turtle, Bmtutl)基因表达水平的影响,为揭示家蚕微孢子虫的侵染机制奠定基础。【方法】利用生物信息学方法对家蚕海龟蛋白3种亚型Bmtutl-464, Bmtutl-519和Bmtutl-810的序列结构特征进行了分析;利用qPCR检测家蚕微孢子虫感染后12, 24, 48, 72, 96和120 h,家蚕幼虫中肠、血淋巴与脂肪体组织中Bmtutl-464, Bmtutl-519和Bmtutl-810基因表达水平的变化情况。【结果】家蚕海龟蛋白3种亚型的二级结构均主要由无规则卷曲、α螺旋、β转角和延伸链组成,其中无规则卷曲所占比例最高。但是PredictProtein分析发现,Bmtutl-464, Bmtutl-519和Bmtutl-810之间的蛋白/多核苷酸结合位点存在较大差异。qPCR结果表明,感染家蚕微孢子虫后,家蚕幼虫中肠、血淋巴与脂肪体组织中Bmtutl-464, Bmtutl-519和Bmtutl-810基因的整体表达处于被抑制状态,尤其在脂肪体中最为明显：Bmtutl-519和Bmtutl-810基因的表达在家蚕微孢子虫感染家蚕后的72 h开始受到显著抑制,特别是Bmtutl-519基因,其相对表达水平均不到对照的5.0%。【结论】家蚕海龟蛋白这3种亚型的序列结构特征存在较大差异,家蚕微孢子虫感染在一定程度抑制了家蚕幼虫中肠、血淋巴与脂肪体组织中Bmtutl-464, Bmtutl-519和Bmtutl-810基因尤其是Bmtutl-519的表达。结果说明,与其他两种家蚕海龟蛋白亚型相比,Bmtutl-519蛋白可能在家蚕微孢子虫侵染宿主的过程中起主要作用。     

特殊基因突变增加脑动脉瘤风险

科学家对转基因产品的安全性一直持有争论,日前,奥地利科学家研究发现,长期食用MON810型转基因玉米会使实验鼠生育能力下降,而且后代重量轻、体质弱。     

云南不同类型一季稻产量形成及其与气象因子的关系

利用云南省14个不同海拔农业气象观测站1994-2010年水稻大田发育期和产量观测资料,研究水稻产量形成及气象因子对低产水稻产量构成因素的影响;根据14个站点水稻产量构成因素的系统聚类分析结果和水稻类型,将水稻分为低产粳型、低产籼型、高产粳型和高产籼型4个类型.对这4类水稻产量构成因素的分析结果表明,单位面积颖花量与产量呈极显著正相关,低产粳型水稻产量主要受结实率和颖花量影响,其他3类颖花量对产量影响较大.低产粳型水稻主要受低温的影响,孕穗期低温降低颖花量和有效穗数,孕穗期和抽穗开花期低温增加空壳率,以平均气温、平均最高气温和冷积温的影响较大;乳熟前期较低的平均气温增加秕谷率,同时降低千粒重.低产籼型水稻产量构成因素受多种气象因子的综合影响明显;分蘖期和拔节期一定程度的增温不利于增加低产籼型水稻有效穗数,而分蘖期较多的日照时数和较大的平均气温日较差有利于有效穗数的增加,分蘖期和拔节期气温和日照时数与每穗粒数的关系呈“抛物线型”;低产籼型水稻空壳率一定程度上受抽穗开花期低温的影响,而乳熟前期高温少雨不仅增加秕谷率,还导致千粒重明显下降.     

不同生育期持续干旱对玉米的影响及其与减产率的定量关系

为了探究不同生长阶段土壤水分含量持续下降过程对玉米生长发育和产量形成的影响,通过设置遮雨棚人工控水试验,分析不同生长阶段持续干旱条件下玉米株高、叶面积指数(LAI)、光合性能、地上生物量和产量等生理生态指标的动态变化.试验因素为控水时段和控水持续时间,从拔节普遍期开始分别控水20(T₁)和27 d(T₂),从抽雄普遍期开始控水20(T₃)和27 d(T₄),加上不控水对照(CK),共5个处理.结果表明: 持续干旱导致植株叶片卷曲、打绺,下部叶片衰老加快,对LAI影响较大,从而降低生物量的累积与籽粒产量.T₁～T₄处理结束时LAI分别为CK的74.9%、68.2%、60.5%和48.3%.玉米植株在经历持续控水后,叶片最大净光合速率(P_{n max})逐渐下降,T₁(T₃)和T₂(T₄)处理结束时P_{n max}分别降至CK的23%及不足10%,复水2周后,P_{n max}能恢复到CK的90%左右.T₁和T₂处理产量较CK分别下降18.5%和24.0%,T₃和T₄处理分别减产41.6%和45.8%.抽雄期持续干旱对玉米地上生物量及产量构成的影响大于拔节期干旱.干旱程度(D)能够定量表示土壤干旱状况,与玉米减产率存在线性定量关系,可通过计算D来预测玉米的减产情况.     

苹果绵蚜为害产量损失测定

苹果绵蚜为害苹果的树干、枝,新稍及根部,从中吸取大量营养,使寄主生长发育不良,产量降低。经测定苹果绵蚜发生群落数与造成的产量呈负相关,而与产量损失率成正相关,在苹果单株产量108．19～154．20kg,苹果绵蚜群落数±30～＞150个的情况下,小国光和青香蕉品种的产量损失率分别为4．10％～38．81％和7．5％～32．04％。     

Epistatic gene effects on the yield of the parents of F1, F2, BC1 and BC2 progeny

The genetic analysis of 5 tomato hybrids (Danubius F₁, Luna F₁, Lido F₁, Balkan F₁ and Mi-10 F₁) was made. We produced their F₁, F₂, BC₁ and BC₂ generations and analysed their yield (on the first three flower branches) as well as some of the yield components of tomato fruits (mean fruit weight, mean fruit weight on the first flower branch, fruit length, fruit width, and number of locules). In order to estimate the gene effects, we applied the additive-dominance mode with three and six parameters. Epistatic gene effects were estimated by applying the six-parameter mode (Mather and Jinks 1982). As for yield and yield components, there were significant differences between the mean values of parents and their progeny. On the basis of the investigated genetic parameters, the obtained results suggested that the additive and dominance gene effects prevailed in the yield and yield components (Danubius F₁, Luna F₁, Lido F₁, Mi-10 F₁), whereas epistatic gene effects were excluded. As for the hybrid Balkan F₁, we recorded significant gene effects, both the additive and the dominance ones in the yield inheritance: additive x additive and dominance x dominance (with the negative sign). The estimated values of the epistatic gene effects were the most prominent in inheriting the feature average fruit weight on the first flower branch — additive x dominance gene effects. They represented the most frequent type of the interallele interaction recorded in the investigated hybrids.     

利用分子标记预测杂交水稻产量及其构成因素

利用AFLP、RAPD、SSR技术分析了10个恢复系和5个不育系的931个基因座,利用15个亲本配制了50个杂交组合,在泸州和重庆2个环境下同时种植,考察了产量及其构成因素,从931个基因座中筛选出了与之相关的阳性座位、增效座位、减效座位、非环境型座位,并分析了它们与杂种产量及其构成因素间的关系。结果表明,利用所有座位计算的遗传差异与产量及其构成因素的相关性,绝大多数性状未达显著水平,不能直接用于预测产量及其构成因素。阳性座位在一定程度上可以提高相关系数,因性状不同而存在差异,在多数性状上预测产量及其构成因素还有一定难度;增效座位和减效座位可以大幅度提高相关系数,在不同的环境下也表现一致,可以用来预测产量及其构成因素;非环境型座位计算的相关系数也较高,但低于增效座位和减效座位,说明环境对产量及其构成因素有较大的影响。     

利用重组自交系进行陆地棉产量及产量构成因子性状的QTL定位

以高产陆地棉栽培品种中棉所12和8891的杂交组合湘杂棉2号为材料,采用单粒传法构建了含有180个家系的重组自交系(RILs)群体。本研究的目的是分析产量及其构成因子的相互关系并进行相应的QTL定位。重组自交系群体、两亲本和F1于2002年、2003年分别种植于南京农业大学江浦实验农场和江苏省灌云棉花基地。收获每行中间五株的籽棉并考察产量及产量构成因子性状。调查的产量及产量构成因子性状包括单株籽棉产量、单株皮棉产量、单株铃数、铃重、衣分、衣指和籽指。筛选了4,106对SSR引物和384个AFLP引物组合,分别得到127和18个多态位点;此外,2个RAPD引物、1个SRAP引物组合以及来自亲本8891的显性黄花药基因P1也被用来作为标记检测群体基因型。最终共获得149个多态位点,其中132个位点分布于26个染色体/连锁群,覆盖865.20cM,约占棉花基因组的18.57%,标记间平均距离6.55cM。利用此遗传图谱结合重组自交系群体3个环境下的产量及产量构成因子性状,应用QTLCartographer2.0的复合区间作图法进行单位点QTL定位。对各环境资料的分离分析共定位出34个QTL,而利用三环境平均值的联合分析定位出15个QTL。本研究定位的QTL可为棉花产量育种提供信息,其中衣分QTLqLP-A10-1在联合分析及分离分析下的两个环境都能检测到,可能对标记辅助选择有实际应用价值。通径分析结果表明,各产量构成因子中,铃数对皮棉产量贡献最大,这与产量构成因素性状在F1的杂种优势表现一致;因此,在棉花育种上,可优先考虑单株铃数并结合其它产量构成因素进行品种选育和杂交组合选配。     

播栽期对水稻产量和产量构成因素及生育期的影响

研究了不同播栽期对水稻产量和产量构成因素及生育期的影响。结果表明 ,随播栽期推迟 ,水稻产量有所降低。每穗成粒数减少是推迟播栽期引起水稻减产的主要原因 ,其次是千粒重的下降和成穗数的降低。针对目前的生产实际 ,提出了一些应对播栽期推迟的技术措施。     

Yield components in Hevea brasiliensis– theoretical considerations

Abstract A theoretical analysis of yield components of Hevea brasiliensis is attempted in this paper. The effect of the major yield components, i.e. initial flow rate per unit length of tapping cut, length of the cut, percentage rubber content and plugging index on rubber yield is represented by the formula Variation in yield within and between clones can be ascribed to variation to any one of the above components. The importance of high growth rate for maintaining high yield throughout the life cycle of the tree is theoretically elucidated. While the present contention of a theoretical maximum yield of 9.5 t ha^?1 with a stand of 350 trees is questioned, the theoretical possibility of attaining that yield by increasing the stand per ha to 600 is analysed.     

Climatic and technological ceilings for Chinese rice stagnation based on yield gaps and yield trend pattern analysis

Climatic or technological ceilings could cause yield stagnation. Thus, identifying the principal reasons for yield stagnation within the context of the local climate and socio‐economic conditions are essential for informing regional agricultural policies. In this study, we identified the climatic and technological ceilings for seven rice‐production regions in China based on yield gaps and on a yield trend pattern analysis for the period 1980–2010. The results indicate that 54.9% of the counties sampled experienced yield stagnation since the 1980. The potential yield ceilings in northern and eastern China decreased to a greater extent than in other regions due to the accompanying climate effects of increases in temperature and decreases in radiation. This may be associated with yield stagnation and halt occurring in approximately 49.8–57.0% of the sampled counties in these areas. South‐western China exhibited a promising scope for yield improvement, showing the greatest yield gap (30.6%), whereas the yields were stagnant in 58.4% of the sampled counties. This finding suggests that efforts to overcome the technological ceiling must be given priority so that the available exploitable yield gap can be achieved. North‐eastern China, however, represents a noteworthy exception. In the north‐central area of this region, climate change has increased the yield potential ceiling, and this increase has been accompanied by the most rapid increase in actual yield: 1.02 ton ha^?1 per decade. Therefore, north‐eastern China shows a great potential for rice production, which is favoured by the current climate conditions and available technology level. Additional environmentally friendly economic incentives might be considered in this region.     

Diversification practices reduce organic to conventional yield gap

Agriculture today places great strains on biodiversity, soils, water and the atmosphere, and these strains will be exacerbated if current trends in population growth, meat and energy consumption, and food waste continue. Thus, farming systems that are both highly productive and minimize environmental harms are critically needed. How organic agriculture may contribute to world food production has been subject to vigorous debate over the past decade. Here, we revisit this topic comparing organic and conventional yields with a new meta-dataset three times larger than previously used (115 studies containing more than 1000 observations) and a new hierarchical analytical framework that can better account for the heterogeneity and structure in the data. We find organic yields are only 19.2% (±3.7%) lower than conventional yields, a smaller yield gap than previous estimates. More importantly, we find entirely different effects of crop types and management practices on the yield gap compared with previous studies. For example, we found no significant differences in yields for leguminous versus non-leguminous crops, perennials versus annuals or developed versus developing countries. Instead, we found the novel result that two agricultural diversification practices, multi-cropping and crop rotations, substantially reduce the yield gap (to 9 ± 4% and 8 ± 5%, respectively) when the methods were applied in only organic systems. These promising results, based on robust analysis of a larger meta-dataset, suggest that appropriate investment in agroecological research to improve organic management systems could greatly reduce or eliminate the yield gap for some crops or regions.