新疆甘草属的种间杂交

试验以居群为单位的新疆甘草属７个种进行种间人工杂交。通过对种间杂交结实量（ＲＳ）和亲本种平均结实量（ＲＳｍ和ＲＳｆ）的分析比较,测出相应的杂交结实指数（ＩＳ）、初步了解种间杂交亲和性的大小,为甘草属植物系统与演化的研究提供参考依据。     

生物学中的物理量及其单位的正确使用法

生物学中的物理量及其单位的正确使用法李寿星（湖北农学院荆州４３４１０３）自１９６０年第１１届国际计量大会通过国际单位制（ＳＩ）并于１９７１年的第１４届国际计量大会予以完善后,世界各国和各学科领域相继进行了以ＳＩ为基础的计量单位改革。我国国务院１９８４...     

激光生物学诸领域应重视量名称、量符号的规范使用

激光生物学诸领域,在日常工作、科研、教学、论文书写中,使用有关量、单位、各类符号的机会甚多,使用得当不仅可简化表示方法,且对论文书刊的标准化,规范化具有重要意义。本文先就有关量名称、量符号的规范使用,特别是容易引起混淆与误解的几个常用辐射量的区别与联系,图表中量和单位的正确表示方法、使用不当的有关情况及其解决方法等进行了简要的介绍与讨论,望能引起广大读作者的重视。     

激光扫描共聚焦显微镜（LSCM）及其生物学应用

激光扫描共聚焦显微镜（ＬＳＣＭ）有效地排除了非焦平面信息,提高了分辨率及对比度,使图像更为精确清晰;与计算机及相应的软件技术组合,ＬＳＣＭ 实现了连续光学切片,广泛应用于生物三维结构重组及动态分析。目前,激光共聚焦显微技术已成功应用于生物芯片技术、激光显微操作系统、细胞骨架研究、生理生化及胚胎学研究、基因定位等领域。多光子技术的发展,进一步改善了ＬＳＣＭ 成像清晰度,拓宽了ＬＳＣＭ 在生物学领域中的应用。本文叙述了ＬＳＣＭ 的基本原理及其在生物学研究中的应用。     

施用不同量有机肥的盆栽苹果土壤中生长素及细胞分裂素含量 …

利用酶联免疫检测法（ＥＬＩＳＡ）测定施用不同量有机肥盆栽苹果土壤中生长素（ＩＡＡ）及细胞分裂素（ＣＴＫ）含量的结果表明，土壤中存在可以用８０％甲醇提取的植物激素，有机质含量高的土壤中ＩＡＡ及ＣＴＫ含量明显较高。     

植物叶片对硒的吸收与转运

以花生为供试植物的叶面施硒试验结果表明,叶片能够吸收利用Ｓｅ（ＩＶ）和Ｓｅ（ＶＩ）两种价态的外源硒,并将所吸收的硒主要转运至花生种子中去。叶片对硒的吸收转运能力受施硒量、施硒时间和硒的价态等因素的影响,叶片对Ｓｅ（ＶＩ）的吸收能力约是Ｓｅ（ＩＶ）的３倍,吸收量与施硒量成正比,在花针期施用有利于叶片的吸收利用和转运．     

渤海湾对虾发生量与补充量动态特征的研究

每年５月中旬和８月初,在中国对虾（Ｐｅｎａｅｕｓｃｈｉｎｅｎｓｉｓ）的主要产卵场———渤海湾进行产卵场和栖息地调查,分别获取卵子／幼体和幼虾相对资源量,把卵子／幼体密度视为亲体数量（Ｓｔ）的一个相对数值,把幼虾相对资源量视为补充量（Ｒｔ）的一个相对数值,用Ｒｉｃｋｅｒ模式（Ｒｔ＝ａＳｔｅ－ｂＳｔ）拟合资料,有：ａ＝２９２２４３;ｂ＝００６９;Ｒ２＝０４７;Ｐ＜０００５。结果表明：对虾的发生量对其补充量的控制程度近５０％。通过回归分析,确证了对虾早期发育阶段栖息地的降雨量、大风、日照和黄河径流量等环境因素对卵子／幼体的成活率乃至对补充量的重要影响     

人T细胞白血病病霉Ⅰ型env基因的克隆与表达

本文通过聚合酶链式反应（ＰＣＲ）,从整合有人Ｔ细胞白血病病毒Ⅰ型（ＨＴＬＶ－Ｉ）的ＭＴ－２细胞株中,扩增出ＨＴＬＶ－Ｉ外膜蛋白（ｅｎｖ）的全基因（１．４５ｋｂ）,并成功地克隆入ｐＵＣ１９载体,构建成ｅｎｖ基因克隆ｅｎｖ／ｐＵＣ１９．利用原核高效表达载体ｐＧＥＸ－２Ｔ,在大肠杆菌中有效地表达了与谷胱甘肽Ｓ－转移酶（ＧＳＴ）融合的ｅｎｖ羧基末端抗原的重组蛋白,融合基因的转录由ｔａｃ启动子调控。ＳＤＳ－ＰＡＧＥ结果表明,有一约５２ｋＤ的目的蛋白带,表达量占菌体总蛋白的１０％;ＷｅｓｔｅｒＮｂｌｏｔｔ及ＥＬＩＳＡ结果显示,表达产物能与ＨＴＬＶ－Ｉ多抗血清结合。本研究为研制ＨＴＬＶ－Ｉ的诊断试剂及进一步了解ｅｎｖ的免疫学和生物学性质打下了基础。     

鳜鱼传染性脾肾坏死病毒(ISKNV)PCR检测方法的建立及虹彩病毒新证据

利用真鲷虹彩病毒（ＲＳＩＶ）核苷酸还原酶小亚单位（ＲＮＲＳ）基因保守区设计的一对引物,建立了鳜鱼传染性脾肾坏死病毒（ＩＳＫＮＶ）特异的ＰＣＲ检测体系。运用该体系检测ＩＳＫＮＶ,具有简便、快速、敏感、特异等特点,为诊断与预防ＩＳＫＮＶ提供了一个重要的手段。通过对ＰＣＲ产物的克隆与序列分析,发现ＩＳＫＮＶ ＰＣＲ扩增产物与ＲＳＩＶ ＲＮＲＳ基因相应序列的同源性很高,达到９２．５％,进一步证明ＩＳＫＮＶ     

PRK,LASIK技术在中国的应用

准分子激光屈光性角膜切削术（ＰＲＫ）和准分子激光原位角膜磨镶术（ＬＡＳＩＫ）是一种治疗眼球屈光不正的新技术,美国、德国、日本和中国（台湾）等国发展了多种准分子激光屈光治疗机以及相应的手术器械及软件,我国从１９９３年引进第一台ＰＲＫ机以来,已引进近百台机器,治疗屈光不正病例已超过十万。作者通过问卷调查和专家访问,对ＰＲＫ、ＬＡＳＩＫ技术在中国的应用状况进行了调查,在调查的基础上进行了分析,并对ＰＲＫ     

A new method to measure and calculate light intensity and light quality simultaneously by using portable spectrometer

The influence of light intensity and light quality on plants is highly concerned in the field of plant physiology and ecology. However, the calibrated quantum meter for measurement of light intensity cannot measure light quality, and vice versa. Here we developed an empirical formula to convert light energy to photon flux density, based on the measurement conditions of spectrometer. Under the guide of the formula, a portable spectrometer (AvaSpec-ULS2048×64) was calibrated by using four narrowband light emitting diode (LEDs) in combination with a calibrated quantum meter (LI-190SB). After calibration of the spectrometer, we can calculate photosynthetic photon flux density (PPFD or PAR) and measure spectrum of radiation flux simultaneously. Under natural light conditions, the errors between measured and calculated PPFDs are in the range from -2% to 5%, indicating the reliability of the method. With this new approach, the application of portable spectrometer can be greatly broadened: 1) the light intensity and quality of light source and plant growth light environment can be obtained simultaneously, 2) PPFD can be obtained within any specified wavelength range, and 3) there is no need to use standard light source to obtain the absolute light/radiation flux of a spectrum measured by spectrometer. In conclusion, this method has potential applications for the study of plant physiology and ecology.     

用便携式光谱仪同步测定和计算光强和光质的新方法

外界光强和光质对植物的影响在植物生理生态研究领域中一直受到高度关注。而测定光强的光量子计不能测定光质; 测定光质的光谱仪不能直接测定光强, 两者均不能同步测定光强和光质。该文作者建立了一个基于光谱仪测定条件的能量与光量子的经验转换公式, 用4只不同波长的窄带发光二极管(LED)光源结合光量子计(LI-190SB)对便携式光谱仪(AvaSpec-ULS2048×64)所获得的光谱进行了快速标定, 实现了用便携式光谱仪同步直接测定光量子通量密度和光质的目的。在自然光照条件下, 采用转换公式计算出光量子通量密度(PPFD)与实测的PPFD之间误差在-2%-5%范围内, 证实了这种方法的可靠性。通过这个新方法, 可以极大地拓宽便携式光谱仪的适用范围: 1)实验室内或野外只需用便携式光谱仪即可对光源及植物生长的光强和光质环境进行同步精确测定和计算; 2)可以计算光谱仪测定范围内任意波长区段的光量子通量密度; 3)无需采用标准光源即可获得绝对辐射(光)通量值。因此, 这项技术在植物生理生态研究领域具有广阔的应用前景。     

Light measurement and the terminology of low

Abstract. This paper (i) considers the measurement of light in terms of the flow of radiant energy or of particles in a vector field; (ii) derives terminology and units for the specification of light as a flow of radiant energy or of photons which satisfy both the requirements of SI and are physically consistent and (iii) recommends that this terminology is adopted by all plant scientists to avoid ambiguity, confusion and the proliferation of synonyms when reporting light measurements.     

The effect of the dark interval in intermittent light on thylakoid development: photosynthetic unit formation and light harvesting protein accumulation

Etiolated bean plants were grown in intermittent light with dark intervals of shorter or longer duration, to modulate the rate of chlorophyll accumulation, relative to that of the other thylakoid components formed. We thus produced conditions under which chlorophyll becomes more or less a limiting factor. We then tested whether LHC complexes can be incorporated in the thylakoid. It was found that an equal amount of chlorophyll, formed under the same total irradiation received, may be used for the stabilization of few and large-in-size PS units containing LHC components (short dark-interval intermittent light), or for the stabilization of many and small-in-size PS units with no LHC components (long dark-interval intermittent light). The size of the PS units diminishes as the dark-interval duration is increased, with no further change after 98 minutes. The PSII/cytf ratio remains constant throughout development in intermittent light and equal to that of mature chloroplasts (PSII/cytf = 1) except in the case of very long dark-interval regimes, where about half PSII units per cytf are present. The PSII/PSI ratio was found to be correlated with the PSII unit size (the larger the size, the lower the ratio). The number of PSI units operating on the same electron transfer chain varied depending on the size of the PSII unit (the larger the PSII unit size, the more the PSI units per chain). The results suggest that it is not the chlorophyll content per se which regulates the stabilization of LHC in developing thylakoids and consequently the size of the PS units, but rather the rate by which it is accumulated, relative to that of the other thylakoid components.Abbreviations Chl Chlorophyll - CL Continuous light - CPa the reaction center complex of PSII - CPI the reaction center complex of PSI - CPIa Chlorophyll protein complex containing the CPI and the light harvesting complex of PSI - fr w fresh weight - LDC Light dark cycles - LHC-I Light-harvesting complex of PSI - LHC-II Light harvesting complex of PSII - PS photosystem - PSI photosystem I - PSII photosystem II     

Assessment of the photosynthetically active incident radiation on outdoor photobioreactors using oxalic acid/uranyl sulfate chemical actinometer

A simple actinometric method was evaluated formeasuring the photosynthetically active incidentphoton flux on outdoor photobioreactors. The method isbased on uranyl sulfate catalyzed photodecompositionof oxalic acid in presence of light. The uranyl–oxalate chemical actinometer absorbs radiation ofwavelengths below 535 nm. In the present work, thephotobioreactor wall material did not transmit lightenergy of wavelengths below 350 nm and the effectiveabsorptivity method was used to evaluate the photonflux between 350–535 nm. The standard solar spectrumof the American Society for Testing and Materials(ASTM) was employed for estimating the ratio betweenthe photosynthetically active radiation (400–700 nm)and the solar radiation in the 350–535 nm range. Thisratio (2.21) was taken to be equal to the quotientbetween the photosynthetically active radiation (PAR)and the incident photon flux on the photobioreactor'ssurface (for the solar radiation between 350–535 nm).PAR measurements with 4 spherical and 2quantum sensors were used to validate the method.     

Immunoreactive inhibin in follicular fluid is related to meiotic stage of the oocyte during final maturation of the porcine follicle

The concentration and content of inhibin was determined in individual porcine follicles from gilts ovariectomized at various times after the onset of estrus. In one experiment, gilts (n = 5) were ovariectomized at 0, 10, or 20 hr after the onset of estrus and the follicular fluids from all large follicles individually aspirated. In a second experiment, gilts (n = 6) were ovariectomized at 21, 24, 27, 30, or 34 hr after the onset of estrus; follicular fluids were aspirated; and each oocyte was stained and evaluated for cytogenetic stage of meiotic maturation. Inhibin was determined in diluted follicular fluids with a radioimmunoassay based on a synthetic peptide replica of part of the alpha subunit of porcine inhibin. Inhibin values were expressed in terms of thousands of units (kU) of a World Health Organization inhibin standard (86/690). Concentration of inhibin did not vary among hours (overall mean 248 kU/ml). Total follicular content of inhibin also was not different among hours (overall mean 57 kU/follicle). When follicles were classified on the basis of the maturation of the oocyte, significant differences were found. Concentration of inhibin in follicles with a germinal vesicle-stage oocyte was 138 kU/ml, whereas follicles with more mature oocytes had concentrations of between 204 and 254 kU/ml. Follicular content of inhibin showed a similar pattern with 34.9 kU/follicle at germinal vesicle stage, increasing to 42.5-56.1 kU/follicle at later stages. Quantities of inhibin were also negatively skewed and were positively correlated to follicular content of estradiol and dermatan sulfate.     

Grassland canopy composition and spatial heterogeneity in the light quality

Both vertical and horizontal heterogeneity in red light levels and in the red/far red ratio were measured in a mountain grassland and correlated with the vegetation structure. Vertical change in the red/far red ratio was measured in three communities; canopy structure and density was investigated by the point-quadrat method and biomass harvesting. Quantities of both grasses and dicots were significantly correlated with R/FR ratio and red light intensity at ground level. In dicots, percentage cover determines their effect on light levels; in contrast, no single parameter suffices to capture the effect of grasses: grass biomass, number of hits (cover) and the mean height (distance from the soil surface) of grass hits are of importance. This indicates strikingly different geometry and optical properties of both plant groups.The fine-scale horizontal heterogeneity was assessed by means of a grid of 3.3×3.3 cm cells (plots of 8× cells) in the species-poor community. Both red light and R/FR ratio were determined at soil level in all the grid cells; fine-scale vegetation recording was done by counting all rooted stems (leaves for large rosette plants) in these cells. Spatial autocorrelation (Moran's I) of fine-scale heterogeneity in light levels, biomass per cell and individual species occurrences revealed many significant autocorrelations. Light levels (particularly red light) show autocorrelations at the distance of 1–2 cells (3.3–6.7 cm); biomass shows little autocorrelation. A multivariate analysis (redundancy analysis) showed that cellwise densities of two species had significant and systematic correlations with the light levels (both red light and R/FR ratio): a grass species with wide, mainly horizontal leaves, Anthoxanthum alpinum, was negatively correlated with light levels; Nardus stricta, with upright and narrow leaves and stems was positively correlated with light levels.     

Linking Material Flow Analysis with Environmental Impact Potential

Technology transition can have significant implications on the evolution of environmental impact potential of disposed electronics over time. Considering technology transition, we quantify the temporal behavior of ecological and human health impact potential from select heavy metals in electronic waste (e‐waste). The case study analyzes product substitution effects in two electronic cohorts from the U.S. market: (1) computers (laptops substituting for desktops) and (2) televisions (flat‐panel liquid crystal displays [LCDs] and plasma displays substituting for cathode‐ray tubes [CRTs]). Quantities of end‐of‐life (EoL) units to year 2030 are forecasted by the unique combination of dynamic material flow analysis, logistic trend analysis, and product lifespan calibration methods. Metal content from EoL units are assessed via a pathway and effect model using USETox? characterization factors to determine the toxicity potential attributed to heavy metal releases into different media (e.g., air, water, and soil) as an indicator of environmental burden. Results show high impact materials such as lead, nickel, and zinc cause changes in human health toxicity potential and copper causes changes in ecological toxicity potential. Effects of dematerialization, such as reduced metal content in laptops over desktops, provide some positive benefits in toxicity potential per product. However, from a market perspective, emerging e‐waste quantities created by increasing per capita penetration rates of electronics and increasing population will offset gains in environmental performance at the product level. The resulting analysis provides guidance on the timing expected for emerging EoL units and an indication of high impact potential materials requiring pollution prevention as product substitution occurs.     

马占相思子叶离体培养中细胞早期变化的研究

用光学和电子显微镜观察马占相思子叶在离体培养中的细胞早期变化,结果表明,未培养的子叶薄壁细胞内充满大量贮藏物质,在脱分化过程中,贮藏物质逐渐减少,细胞核体积增大,液泡蛋白体出现,质体转化为原质体,线粒体,内质网等细胞器数量增加,马脱分化启动后的细胞分裂方式进行了讨论。     

Leaf photosynthetic light response: a mechanistic model for scaling photosynthesis to leaves and canopies

1. The response of photosynthesis to radiation is an often-studied but poorly understood process, represented empirically in most photosynthesis models. However, in scaling photosynthesis from leaf to canopy, predictions of canopy photosynthesis are very sensitive to parameters describing the response of leaves to Photosynthetic Photon Flux Density (PPFD).
2. In this study, a mechanistic, yet still simple, approach is presented that models the degree of light saturation in leaves explicitly, assuming a heterogeneous environment of PPFD and chlorophyll.
3. Possible mechanisms determining the ratio of chlorophyll to nitrogen are considered, including a direct dependence on PPFD, a mechanism involving the red/far-red ratio of light in the canopy, and an approach based upon maximizing photosynthesis.
4. Comparison of model predictions with two data sets of light, nitrogen and chlorophyll from canopies of Populus and Corylus suggests that the red/far-red mechanism is the most realistic. The data also show that the trees studied do not always optimize their nitrogen partitioning to maximize photosynthetic yield.
5. We then apply the model to the data sets, to predict the shape of light response curves of leaves within canopies and assess the applicability of simple scaling schemes, in which full acclimation of photosynthesis to PPFD justifies the use of big-leaf models. We conclude that, at least for the data used, basic assumptions of such schemes do not hold.