激光共聚焦显微镜与光学显微镜之比较

激光扫描共聚焦显微镜在活细胞的动态检测、光学切片和三维结构重建等方面较光学显微镜有质的飞跃。本文对激光扫描共聚焦显微镜和光学显微镜进行了比较和讨论,并简单介绍多光子激光扫描显微镜。     

Light and Electron Microscope Studies of Some Annelid Setae

An account of a light and electron microscope study of the setae of Disoma multisetosum, Pectinaria belgica (Polychaeta sedentaria) and Echiurus echiurus (Echiuroidea) is given. The results are compared with those of previous researchers, and the possibility of using the ultrastructure of the “annelid seta” as a phylogenetic-systematic instrument is preliminarily discussed.     

How to Increase the Effective Depth of Focus of the Light Microscope for Photography

Photography of objects whose dimensions exceed the depth of focus of 8 given objective may be effected by dividing the total necessary exposure between multiple underex-Posures on the same piece of film with the microscope focused at different levels.     

供光学显微镜观察的花粉样品制备的一种简单方法

传统的制备供光学显微镜观察的花粉样品的方法 (中国科学院植物研究所形态室孢粉组 ,1 960 )不但程序复杂 ,而且不同种类的花粉容易混杂。最近 ,我们在进行山茶属(Ｃａｍｅｌｌｉａ)花粉形态的系统研究中总结出一种制备供光镜观察的花粉材料的简单方法 ,现将其过程介绍如下 :( 1 )从标本或新鲜植株上取下花药 ,用冰醋酸浸软后 ,置洁净的凹玻片 (单凹玻片 )上 ,于解剖镜下将花药打开 ,滴上 95%酒精将花粉洗出。( 2 )滴上预先配制好的分解液 (醋酸酐 9份和浓硫酸 1份 ) ,于室温下或 50℃恒温箱里放置 5ｍｉｎ(具体温度和时间因花粉种类而异 ) …     

Avian Trypanosome Division; A Light and Electron Microscope Study1

SYNOPSIS. A magpie isolate of Trypanosoma avium was studied using cultured epimastigotes and trypomastigotes from experimentally infected canaries. Apparent signs of division (double nuclei, flagella, and kinetoplasts) were observed in trypomastigote forms with the light microscope. Three or 4 flagella were seen within a single flagellar pocket in epimastigotes by electron microscopy. It is suggested that apparently dividing trypomastigotes are actually blocked in the process of division.     

Study of Major Chemical Components of Pseudotaxus chienii

Genus Pseudotaxus distributed in the Zhejiang, Hunan, Jiangxi etc. is endemic to China. Only one species is envolved in the genus. A preliminary investigation on chemical components of Pseudotaxus is reported in the present paper. Three crystalline substances have been isolated from trunk of P. chienii grown in Zhejiang and have been identified as llβ, 22-dihydroxyhopane (Ⅰ), β-sitosterol (Ⅱ) and tsugalacton (Ⅲ) respectively by chemical and spectral (IR, NMR, MS) analyses.     

Light and Electron Microscope Study of Dunaliella primolecta Butcher (Volvocida)*

SYNOPSIS. Light and electron microscope observations on Dunaliella primolecta Butcher from logarithmic and stationary phases of batch cultures are correlated. Except for the lack of a cell wall the fine structure has typical volvocid features. The transition from logarithmic to stationary phase is marked by changes in content and size of cytoplasmic vacuoles, accumulation of cytoplasmic lipid, accumulation of starch in the plastid matrix, and by the formation of autophagosome-like bodies. The organelles in stationary-phase flagellates are closely packed together because of the cytoplasmic lipid and starch-distended chloroplast. Organisms from logarithmic phase have an abundant ribosome-packed groundplasm supporting the organelles. In the cytochemical demonstration of acid phosphatase activity, Golgi cisternae and smooth and coated Golgi vesicles contain Gomori reaction product. The possible roles of the Golgi apparatus in this flagellate are discussed.     

CEREBELLAR GRANULE CELLS IN VITRO : A Light and Electron Microscope Study

The behavior of granule cells in mature cerebellar cultures derived from newborn mice was studied by light and electron microscopy. Many granule cells remained in the explants as an external granular layer. These cells were differentiated, as evidenced by formation of bundles of parallel fibers and by development of synapses between granule cell axons and Purkinje cell branchlet spines, and between Golgi cell axons and granule cell dendrites. Although the over-all architecture of the cerebellar explants after 18–33 days in vitro was similar to that of the newborn mouse, the evident differentiation of the granule cells suggested that interneuronal relationships resemble those of the mature cerebellum in vivo.     

A Light and Electron Microscope Study of the Epithelial Cells of the Gut of Fasciola hepatica L

The structure of the epithelial cells of the alimentary tract of Fasciola hepatica was investigated by means of light and electron microscopy. Tissue prepared for electron microscopy was fixed in 1 per cent osmium tetroxide, buffered with veronal to a pH of 7.4, and embedded in butyl methacrylate with 1 per cent benzoyl peroxide as a catalyst. Polymerisation was carried out at 60°C. The majority, if not all, the epithelial cells pass through both absorptive and secretory cycles. The free ends of absorptive cells possess fine protoplasmic processes that project into the lumen of the gut. These are apparently concerned with the absorption of nutriment. In electron micrographs, the protoplasmic (absorptive) processes are frequently seen to be in the form of tubular loops both ends of which arise from the same cell. The free end of a process is often expanded into a ribbon-like structure. Each process possesses an external limiting membrane and an internal membranous ultrastructure. When a cell becomes glandular in function, the protoplasmic processes seem to become less numerous. The plasma membrane is invaginated into the basal part of an absorptive cell. In the neighbourhood of the lumen of the gut where two tall cells are in contact, bands of amorphous cytoplasmic material are in contact with each cell membrane.     

Major Volatile Components Formed from Casein during Roasting

The volatiles, produced from casein during roasting at 250°C for 1 hr, were fractionated and analyzed by various methods including the combination of gas chromatography and mass spectrometry. The following kinds of compounds were tentatively or conclusively identified: six aliphatic aldehydes, benzaldehyde, acetophenone, hydrogen sulfide, methanethiol, dimethyl disulfide, five primary alkylamines, piperidine, N-ethylcyclohexylamine, two alkylpyrazines, ethylmethylpyridine, three aliphatic carboxylic acids, pyruvic acid, benzoic acid, six aliphatic alcohols, and three aromatic hydrocarbons. α-Dicarbonyls were not formed in any detectable amount.

The results obtained above are discussed in comparison with those of pyrolysis of some kinds of α-amino acid and also with those of some roasted foods.     

Effect of Light Quality on Phycobilisome Components of the Cyanobacterium Spirulina platensis

Phycobilisomes from the nonchromatic adapting cyanobacterium Spirulina platensis are composed of a central core containing allophycocyanin and rods with phycocyanin and linker polypeptides in a regular array. Room temperature absorption spectra of phycobilisomes from this organism indicated the presence of phycocyanin and allophycocyanin. However, low temperature absorption spectra showed the association of a phycobiliviolin type of chromophore within phycobilisomes. This chromophore had an absorption maximum at 590 nanometers when phycobilisomes were suspended in 0.75 molar K-phosphate buffer (pH 7.0). Purified phycocyanin from this cyanobacterium was found to consist of three subparticles and the phycobiliviolin type of chromophore was associated with the lowest density subparticle. Circular dichroism spectra of phycocyanin subparticles also indicated the association of this chromophore with the lowest density subparticle. Absorption spectral analysis of α and β subunits of phycocyanin showed that phycobiliviolin type of chromophore was attached to the α subunit, but not the β subunit. Effect of light quality showed that green light enhanced the synthesis of this chromophore as analyzed from the room temperature absorption spectra of phycocyanin subparticles and subunits, while red or white light did not have any effect. Low temperature absorption spectra of phycobilisomes isolated from green, red, and white light conditions also indicated the enhancement of phycobiliviolin type of chromophore under green light.     

A Fluid System for the Cultivation,Light Microscope Examination and Manipulation of Obligate Anaerobes*

A chamber in tandem with oxygen-free gas supply and gas-collecting reservoirs constitutes a system capable of anaerobic maintenance within the range of 0.8–20 μM at 13 C. Cultures contained within the chamber portion of this system are examined through exposed oculars of a microscope otherwise sealed from room atmosphere. Materials are interchanged between the 2 atmospheres through an air lock. Shoulder-length gloves enable all manipulations common to aerobic cultivation procedures without undue restraint.     

Use of Horseradish Peroxidase-Labeled Antibody for Light and Electron Microscope Localization of Reovirus Antigen

Horseradish peroxidase-labeled antibody was used for light and electron microscopic localization of reovirus antigen in tissue culture. Reaction product in infected cells was easily detected in the cytoplasm, and the procedure was as sensitive as the fluorescent-antibody technique. At the electron microscopic level, infected and enzyme-labeled antibody-treated cells showed accumulations of reaction product at the sites of viral replication and around the viral particles. Reaction product was not detected in unstained infected cells, in stained uninfected cells, or in cells infected with an unrelated virus.