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1.
玉米抗倒性与茎秆显微结构的关系 总被引:17,自引:0,他引:17
1989年我们对抗倒性不同的12个杂交玉米进行了解剖观察,发现地面上第三节间的茎外围维管束的长宽、维管束下部厚壁细胞的厚度、皮层厚度与田间倒伏率呈现显著的负相关,同一视野内维管束数目与倒伏率呈显著正相关。 相似文献
2.
玉米抗倒性与茎秆显微结构的关系 总被引:1,自引:0,他引:1
1989年我们对抗倒性不同的12个杂交玉米进行了解剖观察,发现地面上第三节间的茎外围维管束的长宽、维管束下部厚壁细胞的厚度。皮层厚度与田间倒伏率呈现显著的负相关,同一视野内维管束数目与倒伏率呈显著正相关。 相似文献
3.
In this experiment ,the remits of observing under the light microscope and electron microscope, and statistical analysis showed that micronucleus had a certain shape and structure. There was a linear correlation between the micronudeated cell frequency and dosage or the chromosomal aberration frequency in the root tip cells. The micronudeated cell frequency changed according to the different periods of time after irradiation. At the same time, micronuclei that might be synchronous, or not, with the main nucleus for the cell cycle were seen. That means it is possible for some micronuclei induced by irradiation to carry on division. Therefore, the advantages of micronucleus test lies not only in simply and effectively evaluating radiation damage to cells but also in exploring the mechanism of radiation genetics in plant. 相似文献
4.
k-Space image correlation spectroscopy: a method for accurate transport measurements independent of fluorophore photophysics
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We present the theory and application of reciprocal space image correlation spectroscopy (kICS). This technique measures the number density, diffusion coefficient, and velocity of fluorescently labeled macromolecules in a cell membrane imaged on a confocal, two-photon, or total internal reflection fluorescence microscope. In contrast to r-space correlation techniques, we show kICS can recover accurate dynamics even in the presence of complex fluorophore photobleaching and/or "blinking". Furthermore, these quantities can be calculated without nonlinear curve fitting, or any knowledge of the beam radius of the exciting laser. The number densities calculated by kICS are less sensitive to spatial inhomogeneity of the fluorophore distribution than densities measured using image correlation spectroscopy. We use simulations as a proof-of-principle to show that number densities and transport coefficients can be extracted using this technique. We present calibration measurements with fluorescent microspheres imaged on a confocal microscope, which recover Stokes-Einstein diffusion coefficients, and flow velocities that agree with single particle tracking measurements. We also show the application of kICS to measurements of the transport dynamics of alpha5-integrin/enhanced green fluorescent protein constructs in a transfected CHO cell imaged on a total internal reflection fluorescence microscope using charge-coupled device area detection. 相似文献
5.
Culturing embryogenic protoplasts of ‘Hamlin’ sweet orange in calcium alginate beads 总被引:1,自引:0,他引:1
Randell P. Niedz 《Plant Cell, Tissue and Organ Culture》1993,32(1):19-25
Two finely-dispersed, homogeneous and regenerable cell suspension cultures were established from embryogenic callus derived from immature and mature embryos in barley. The quality and viability of suspension cells obtained were determined using differential-interference-contrast microscope and fluorescence microscope. Cell suspension cultures, maintained in modified liquid CC medium, showed a 10-fold increase in dry weight after two weeks with a doubling time of about 3 days. Addition of l-proline and casein hydrolysate in the medium had positive effect on the growth of cell cultures. Subculture interval significantly affected mitotic index. Both cell lines established were able to regenerate plants by somatic embryogenesis, but cell line Z-IM showed much higher regeneration capacity than cell line Z-M. Comparatively high frequencies of variations in chromosome number and structure were found in both lines, and a correlation between karyotype and morphogenic capacity was noticed.Abbreviations KT
kinetin
- BAP
benzylaminopurine
- FDA-PI
fluorescein diacetate and propidium iodide
- 2,4-d
2,4-dichlorophenoxyacetic acid 相似文献
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The use of modernized photometric accessories to a model microscope manufactured by the Leningrad Optico-Mechanical Amalgamation (USSR), as well as the practical application of innovations facilitating and standardizing research work, has made it possible to obtain objective data indicating the presence of significant, direct, linear correlation between infectious activity and the intensity of fluorescence emitted by fluorescent antibodies bound with the antigen of 11 studied variants of Japanese encephalitis virus in continuous cell lines. The study of the dynamics of fluorescence intensity permitted the objective evaluation of the previously revealed regularity in the increase of the intensity of the induced fluorescence of Japanese encephalitis antigen in continuous cell cultures. 相似文献
8.
The morphological change of cellular apoptosis initiates from the change of membrane roughness. In order to identify cellular apoptosis in its early stage, atomic force microscope was adapted to reveal the change of membrane roughness in unprecedented details, providing an image in nanometer-scaled resolution. The mouse monocyte/macrophage cell line RAW 264.7 was the subject studied and subjected to apoptotic induction by hydrogen peroxide. A finding of the qualitative correlation between cell membrane roughness and oxidative stress level is disclosed stating that roughness is increasing with the increasing level of oxidative stress. 相似文献
9.
柠檬醛致黄曲霉孢子丧失萌发力的机制 总被引:12,自引:0,他引:12
通过由倒置显微镜、衍射光栅和线阵光电偶合器件CCD(chargecoupleddevice)等构成的显微多道分光光度系统及由计算机DEPHI编程工具编制的单细胞凝胶电泳SCGE(single cellgelelectro phoresis)图像分析系统 ,摄取荧光显微镜所呈图像 ,再由图像捕捉卡将CCD产生的图像信号送入计算机 ,将柠檬醛对黄曲霉质膜和核DNA损伤的图像进行显示存储和分析处理 ,测定彗星长度、荧光强度、矩类及头尾DNA含量比等彗星参数指标 .结果发现Olive尾矩、尾长、尾分布矩等彗星尾参数指标与柠檬醛致黄曲霉损伤浓度呈正相关性 ,当致损浓度达到 1 5mg L以上时 ,DNA损伤为致死性损伤 ,不能被细胞内修复系统所修复 .揭示柠檬醛通过损伤质膜而进入细胞 ,对DNA产生不可逆损伤 ,使孢子失去萌发力的机制 .实现将DNA损伤的生化定性检测推进到数值化研究范围 ,为柠檬醛的开发应用提供了重要理论依据 .与国内外同类技术相比 ,本检测观察系统还具有高灵敏度、快速、无扰、多光谱显微测定之特点 . 相似文献
10.
建立肺炎支原体镜下观察分级标准,并与测定的CCU和实时荧光定量PCR测定结果进行关联,估算CCU。通过镜下观察肺炎支原体培养浓度和分布范围,确定其分级;采用CCU目测法和实时荧光定量PCR法测定肺炎支原体培养结果,使用等级相关分析方法 Kendall法及Spearman法进行相关性分析。结果显示,肺炎支原体镜下观察标准分为四级,与CCU及实时荧光定量PCR测定值进行关联,呈正相关。镜下观察肺炎支原体的分级越高,则测定的CCU与实时荧光定量PCR值就越高。同时发现菌液稀释104倍数时,各组实时荧光定量PCR测定值均较理想,可作为肺炎支原体培养的最佳培养稀释倍数。结果表明,在肺炎支原体培养过程中,可通过镜下观察估算其CCU,较为简便实用。 相似文献
11.
Terlikowski S Lenczewski A Sulkowska M Famulski W Sulkowski S Kulikowski M 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2001,39(Z2):112-113
The purpose of this retrospective study was to determine whether the intensity of tumor angiogenesis, expressed as microvessel density (MD), is indeed an important parameter predicting lymph node metastasis and survival rate in 73 women operated on for early invasive squamous cell carcinoma of the uterine cervix in stages Ib and IIa (FIGO). Angiogenesis was quantified by light microscope (LM) using an assay for vascular endothelial growth factor (VEGF). In the study, differences were revealed by comparing the MD between both groups. The patient survival with high MD was significantly worse than for those with low MD (p<0.01). A correlation was found between MD and the incidence of lymph node metastases. Hence, quantitative analysis of MD used as the expression of VEGF in the each cervical squamous cell carcinomas could be useful as a significant prognostic indicator. 相似文献
12.
以13种苎麻属植物为试验材料,于植物工艺成熟期取样测定经济性状并用显微镜观察横截面及离析纤维细胞形态,研究苎麻属植物纤维细胞形态结构与其经济性状和物理性能的相关性。结果显示:(1)苎麻属野生种质的纤维细胞外观形态表现与栽培种苎麻基本一致,多呈圆形、多边形、椭圆形和肾形等,形态各异,大小不一。(2)茎秆横截面纤维细胞直径、腔径和纤维胞总数都明显少于对照栽培种,与其原麻产量存在不同程度的正相关性。(3)离析纤维细胞长度、宽度、壁厚和结节数与纤维细度存在不显著负相关,且野生苎麻属种质的细胞长度、宽度明显小于栽培种苎麻。研究表明,野生苎麻属种质在提高栽培种产量上无太大效应,但其在优良纤维基因选育方面和改良栽培种苎麻纤维品质上具有重要应用价值。 相似文献
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The distribution of lead ions in rat peripheral neutrophils was investigated using Timm sulphide silver method. In the neutrophils of adult male rats the Pb-precipitates were electron microscopically localized at 1.5, 3.0 and 6.0 hours after a single intraperitoneal injection of lead at dose 150 mgPb kg b. w. After increased lead ions input to cell matrix a formation of cytoplasmic metal deposits as well as an aggregation of Pb-complexes within deep invaginations of nuclear membrane was detectable. Furthermore, the neutrophils were prepared to examination by scanning electron microscope according to Domaga?a et al. (1979). In neither case there was a clear difference of neutrophil surface morphology between exposed and control populations. The same preparations were then used to X-ray probe microanalysis, and correlation between the presence of Timm reaction product and lead indication was obtained. 相似文献
15.
根据正常细胞、凋亡细胞和坏死细胞的细胞膜对核酸荧光染料的不同选择通透性,用4μmol/L YO-PRO-1(YP)和4μg/ml 碘化丙啶(Propidium iodide, PI)染色96孔板中的细胞样品。分别在485/538 (Ex/Em, nm) 和530/590 (Ex/Em, nm) 的检测波长下借助荧光分光光度计检测细胞样品孔的YP和PI荧光强度。将YP和PI荧光强度值与用荧光显微镜对同一细胞样品细胞凋亡和坏死的定量分析结果相对应,通过对YP荧光强度值与凋亡细胞数的直线回归分析 (r = 0.999,P<0.01),得到依据YP荧光强度值求得凋亡细胞数的直线相关方程。该方法可检测出样品中少至180个的凋亡细胞,具有灵敏度高和快速高效的特点。 相似文献
16.
REBHUN LI 《The Journal of biophysical and biochemical cytology》1956,2(2):159-170
RNA containing yolk nuclei from the surf clam Spisula solidissima have been studied with the light microscope and with the electron microscope. A variety of structures can be seen with both and a correlation can be made between bodies studied with the electron microscope and those studied with the light microscope. The electron microscope shows many of these structures to be composed of double walled lamellae arranged in space, in various ways. The variety of patterns seen with the electron microscope can be satisfactorily explained on the basis of a hypothetical model. The presence of yolk platelets within the yolk nuclei lends support to classical observations on the synthesis of yolk within yolk nuclei or yolk nuclei derivatives. Small granules (about 100 A) are included within the double walled lamellae and their presence probably accounts for the basophilic nature of the entire body. The presence of small granules attached to electron-dense layers relates the yolk nuclei described here to ergastoplasm discussed by others. 相似文献
17.
The size of Rhododendron sichotense seeds and exotesta cells from 20 populations were studied using a scanning electron microscope (SEM). The results of a correlation analysis showed that seed size depends on bioclimatic factors. As a species marker, we used the exotesta cell elongation coefficient. This characteristic was unresponsive to environmental variables, demonstrating its taxonomic significance. In the centre of the species range, the samples had an exotesta cell elongation coefficient that was typical for the species, but in samples from the far northern and southern parts of the range, where the distribution of R. sichotense meets that of of R. dauricum L. and R. mucronulatum Turcz., respectively, the value of the exotesta cell elongation coefficient was intermediate between these species. Therefore, the exotesta cell elongation coefficient can be recommended for use in the detection of hybridisation areas. 相似文献
18.
Measuring elastic properties of cells by evaluation of scanning acoustic microscopy V(Z) values using simplex algorithm 总被引:1,自引:0,他引:1
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In this paper a new technique is proposed to determine the acoustic properties as well as the thickness (and volume) of biological cells. Variations of thickness, density, acoustic wave velocity, stiffness, and attenuation coefficient of a living or dead cell are obtained by scanning the cell by an acoustic microscope. The distance between the cell and the microscope lens is varied and several voltage curves are thus obtained. These curves are then inverted by simplex optimization technique to obtain the cell parameters. The spatial resolution of the method is limited to the resolution of the scanning acoustic microscope. It allows to take advantage of the full range of frequencies and amplification of the microscope. Characteristic distributions of stiffness are exemplified with an endothelial cell in culture. The main part of the thin, lamellar cytoplasm has high stiffness, which drops close to the lamella/cell body transition region and only slightly increases again through the central part of the cell. Acoustic attenuation seems to be related to two factors, cytoplasm accumulation (in the lamellar parts) and scattering in the central part rich in organelles. 相似文献
19.
Tissues from mice were fixed in 1.5% glutaraldehyde, treated for the ultrastructural localization of alkaline phosphatase or Mg++-dependent adenosine triphosphatase, post-fixed in osmium tetroxide, dehydrated and embedded in plastic for electron microscopy. The sites of reaction were visualized in 1-mu plastic sections counterstained with toluidine blue, using a phase contrast microscope. The data show a close correlation between the sites of reaction observed with the phase contrast microscope and the sites studied with the electron microscope. The use of this technique for the study of these phosphatases in normal and pathologic tissues is recommended in order to achieve a high degree of accuracy in selecting a portion of the tissue sample for electron microscopy and to obtain greater resolution in the localization of these enzymes with the light microscope. 相似文献
20.
Paula K. Yu Chandrakumar Balaratnasingam Jing Xu William H. Morgan Zaid Mammo Sherry Han Paul Mackenzie Andrew Merkur Andrew Kirker David Albiani Marinko V. Sarunic Dao-Yi Yu 《PloS one》2015,10(8)
Radial peripapillary capillaries (RPCs) comprise a unique network of capillary beds within the retinal nerve fibre layer (RNFL) and play a critical role in satisfying the nutritional requirements of retinal ganglion cell (RGC) axons. Understanding the topographical and morphological characteristics of these networks through in vivo techniques may improve our understanding about the role of RPCs in RGC axonal health and disease. This study utilizes a novel, non-invasive and label-free optical imaging technique, speckle variance optical coherence tomography (svOCT), for quantitatively studying RPC networks in the human retina. Six different retinal eccentricities from 16 healthy eyes were imaged using svOCT. The same eccentricities were histologically imaged in 9 healthy donor eyes with a confocal scanning laser microscope. Donor eyes were subject to perfusion-based labeling techniques prior to retinal dissection, flat mounting and visualization with the microscope. Capillary density and diameter measurements from each eccentricity in svOCT and histological images were compared. Data from svOCT images were also analysed to determine if there was a correlation between RNFL thickness and RPC density. The results are as follows: (1) The morphological characteristics of RPC networks on svOCT images are comparable to histological images; (2) With the exception of the nasal peripapillary region, there were no significant differences in RPC density measurements between svOCT and histological images; (3) Capillary diameter measurements were significantly greater in svOCT images compared to histology; (4) There is a positive correlation between RPC density and RNFL thickness. The findings in this study suggest that svOCT is a reliable modality for analyzing RPC networks in the human retina. It may therefore be a valuable tool for aiding our understanding about vasculogenic mechanisms that are involved in RGC axonopathies. Further work is required to explore the reason for some of the quantitative differences between svOCT and histology. 相似文献