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1.
2.
黑龙江省三江平原丹顶鹤的数量分布 总被引:2,自引:0,他引:2
在地面调查的基础上,我们使用Y-11轻型飞机对黑龙江省三江平原地区的丹顶鹤的数量分布近行了调查,调查时飞行高度80米,航速140公里/小时,续航里程共3748公里。调查结果表明,丹顶鹤在三江平原主要分布在8个地区,其中嘟噜河下游、洪河自然保护区、七星河流域和兴凯湖低地是主要繁殖地,总数量共309只。 相似文献
3.
J. Ruiz-Herrera J. P. Martinez M. Casanova M. L. Gil R. Sentandreu 《Archives of microbiology》1987,149(2):156-162
Cells from the slime variant of Neurospora crassa were broken in isotonic conditions by use of triethanolamine buffer plus EDTA. After removal of large membranous structures by low-speed centrifugation, chitosomes and secretory vesicles were separated by means of gel filtration, precipitation of membranous contaminants with Concanavalin A, and centrifugation in sucrose or glycerol gradients. Polypeptidic composition of fractions enriched in secretory vesicles or chitosomes was found to be distinct. By these criteria we concluded that chitosomes and secretory vesicles represent different populations of microvesicles. Both microvesicular populations appeared free of endoplasmic reticulum and vacuolar contaminants as demonstrated by determination of appropriate enzymatic markers.Abbreviations ER
Endoplasmic reticulum
- UDP-GlcNAc
uridine-5-diphosphate N-acetyl glucosamine
- GlcNAc
N-acetyl glucosamine
- SDS
sodium dodecyl sulfate
- PMSF
phenyl methyl sulfonyl fluoride
- EDTA
ethylene diamino tetraacetic acid
Investigador Nacional de Mexico. On leave from the Centro de Investigacion y Estudios Avanzados (IPN), and the Universidad de Guanajuato, Gto., Mexico 相似文献
4.
Evidence for the formation of covalent bonds between macromolecules in the domain of the wall of Candida albicans mycelial cells 总被引:9,自引:0,他引:9
V Elorza S Mormeneo F Garcia de la Cruz C Gimeno R Sentandreu 《Biochemical and biophysical research communications》1989,162(3):1118-1125
An O-glycosylated mannoprotein, after its incorporation into the wall, showed an increase in its molecular weight, due at least to its association with N-glycosidic sugar chain(s). This was shown by rendering the material soluble after partial degradation of the wall structure. At present it is unknown whether this phenomenon is due to an additional transglycosylation process or whether the partial degradation of the wall solubilizes a supramolecular structure formed between the original O-glycosylated protein which becomes linked either directly or indirectly through a protein to the N-sugar chain(s). 相似文献
5.
To assess the dynamics of synthesis of the wall by regenerating Candida albicans protoplasts deposition of chitin and mannoproteins were investigated ultrastructurally using wheat germ agglutinin conjugated with either horseradish peroxidase or colloidal gold, and Concanavalin A coupled to ferritin respectively.Freshly prepared protoplasts lacked wheat germ agglutinin receptor sites but after 1–2 h of regeneration, they were detected. After 4–5 h of regeneration, the cell wall showed a discrete structure which was only labelled with wheat germ agglutinin in thin sections. At this stage of regeneration the outermost layer of the wall was labelled with clusters of Concanavalin A-ferritin particles.After 8 h regeneration, the cell wall appeared compact, and homogenously marked with wheat germ agglutinin whereas only the surface layers appeared consistently labelled with Concanavalin A-ferritin.From these observations we conclude that C. albicans protoplasts are able to regenerate in liquid medium a cell wall consisting of a network of chitin fibrils and mannoproteins at least (glucan polymers were not determined in the present cytological study). The former are the fundamental component of the inner layers at early stages of regeneration, whereas the latter molecules are predominant in the outer layers of the wall.Abbreviations WGA-HRP
wheat germ agglutinin conjugated with horseradish peroxidase
- WGA-Au
wheat germ agglutinin conjugated with colloidal gold
- Con A-ferritin
Concanavalin A coupled to ferritin 相似文献
6.
本文报导四川省西部鱼类寄生粘孢子虫粘体虫属六新种,即异型粘体虫,新种Myxosoma disparis sp.nov.,四川粘体虫,新种Myxosoma sichuanensis sp.nov.,光唇粘体虫,新种Myxosoma acrossochilusi sp.nov.鳅粘体虫,新种Myxosoma nemachilusi sp.nov.斜囊粘体虫,新种Myxosoma obliqua sp.nov.,雅安粘体虫,新种Myxosoma yaanensis sp.nov.。 相似文献
7.
Hortensia Rico Enrique Herrero Fernando Miragall Rafael Sentandreu 《Archives of microbiology》1991,156(2):111-114
Depending upon growth temperature, Candida albicans can exhibit two different morphologies, a budding yeast or a mycelium. By studying the distribution of concanavalin A-ferritin particles on the cell wall surface during bud and germ tube formation, we have elucidated the way cell wall extension occurs. Both processes initially require the localized lysis of the wall in order to allow the incorporation of the newly synthesized material. Later on, the cell wall behaves as an elastic structure, allowing extension by an intosusception process and, as a consequence, cell growth.Abbreviation Con A
concanavalin A 相似文献
8.
9.
Prof. Salomon Bartnicki-Garcia Ildiko Bartnicki Rafael Sentandreu 《Current microbiology》1985,12(3):141-145
Whether intact or dissociated with digitonin, chitosomes isolated from the fungusMucor rouxii lack the ability to bind concanavalin A. The absence of external or internal concanavalin A-binding sites distinguishes the chitosome membrane no only from plasma membrane but also from membranes of other organelles (endoplasmic reticulum, mitochondrion, vacuole). This differential binding ability was used to partially separate chitosomal chitin synthetase from major membranes in a crude cell-free extract ofM. rouxii. 相似文献
10.
在鉴定云南叶螨标本时,发现叶螨属一新种,现记述如下。模式标本保存于上海农学院。本文量度单位均为微米。 食禾叶螨Tetranychus graminivorus新种(图1—14) 雌螨 体长(包括喙)454,宽298。椭圆形。浅黄绿色。须肢端感器圆柱形,长6.8, 相似文献