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81.
82.
P F. WHITE 《The Annals of applied biology》1997,131(1):29-42
The sciarid, Lycoriella auripila, is a serious pest of commercial mushroom production. A series of trials demonstrated that the use of early, specifically-targeted, treatments of insecticides and/or antagonists and repellents, which distance treatment time from crop harvest, have the potential to play a useful part in the control of initial and subsequent generations of this pest. Of the treatments examined, those involving a drench treatment of the compost at filling (before pasteurisation) proved to be the most effective. Cyromazine and diflubenzuron were the most active insecticides tested, with cyromazine achieving a superior level of control of the initial infestation. Repellents and antifeedants were also effective, with calcium oxalate and sinapic acid both achieving about 50% control when applied at filling. Treatments applied later during the production cycle, unless in combination with a treatment at filling, were progressively less effective at controlling both the initial sciarid infestation and later generations of larvae. Multiple treatments caused greater reductions in fly populations than did the single treatments and continued to do so throughout the cropping cycle, the greatest reduction in the initial generation (79%) occurring with a triple treatment of cyromazine. With the exception of some diflubenzuron treatments, those that were effective resulted in increases in yield. The use of a physical paper barrier caused significant increases in both fly numbers and total yield. 相似文献
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84.
Immunocytochemical staining of ovarian cyst aspirates with monoclonal antibody against inhibin 总被引:1,自引:0,他引:1
mccluggage w. g., patterson a., white j. and anderson n. h. (1998) Cytopathology 9, 336–342
Immunocytochemical staining of ovarian cyst aspirates with monoclonal antibody against inhibin
Inhibin is a peptide hormone which is produced by ovarian granulosa cells during normal follicular development. It is important that granulosa cells are recognized in fine needle aspirates (FNAs) of ovarian cystic lesions, as this allows definite recognition of a functional cyst and exclusion of a potentially neoplastic epithelial lined cyst. Occasionally the distinction between granulosa and epithelial cells may be difficult, especially when aspirates from functional cysts are unusually cellular. In the present study, FNAs from 33 ovarian cystic lesions were immunostained with a monoclonal antibody against inhibin. Nine cases of peritoneal fluid containing malignant cells in patients subsequently confirmed to have ovarian adenocarcinoma were also stained. Where possible the cytological and immunocytochemical findings were correlated with subsequent biopsy. In most cases in which cytology suggested a functional cyst there was a strong positive staining with anti-inhibin, although occasional cases were negative. One case originally thought to contain epithelial cells stained strongly positive with anti-inhibin and on review was felt to represent a cellular functional cyst. In all other cases where cells were considered to be epithelial there was no staining with anti-inhibin. The study shows that immunocytochemical staining with anti-inhibin may be of value in confirming the presence of granulosa cells, thus establishing a diagnosis of functional cyst. Although negative staining does not exclude a functional cyst, positive staining with anti-inhibin allows exclusion of an epithelial lined cyst and may avoid unnecessary surgical intervention. 相似文献
Immunocytochemical staining of ovarian cyst aspirates with monoclonal antibody against inhibin
Inhibin is a peptide hormone which is produced by ovarian granulosa cells during normal follicular development. It is important that granulosa cells are recognized in fine needle aspirates (FNAs) of ovarian cystic lesions, as this allows definite recognition of a functional cyst and exclusion of a potentially neoplastic epithelial lined cyst. Occasionally the distinction between granulosa and epithelial cells may be difficult, especially when aspirates from functional cysts are unusually cellular. In the present study, FNAs from 33 ovarian cystic lesions were immunostained with a monoclonal antibody against inhibin. Nine cases of peritoneal fluid containing malignant cells in patients subsequently confirmed to have ovarian adenocarcinoma were also stained. Where possible the cytological and immunocytochemical findings were correlated with subsequent biopsy. In most cases in which cytology suggested a functional cyst there was a strong positive staining with anti-inhibin, although occasional cases were negative. One case originally thought to contain epithelial cells stained strongly positive with anti-inhibin and on review was felt to represent a cellular functional cyst. In all other cases where cells were considered to be epithelial there was no staining with anti-inhibin. The study shows that immunocytochemical staining with anti-inhibin may be of value in confirming the presence of granulosa cells, thus establishing a diagnosis of functional cyst. Although negative staining does not exclude a functional cyst, positive staining with anti-inhibin allows exclusion of an epithelial lined cyst and may avoid unnecessary surgical intervention. 相似文献
85.
Plants must develop efficient root architectures to secure access to nutrients and water in soil. This is achieved during plant development through a series of expansion and branching processes, mostly in the proximity of root apical meristems, where the plant senses the environment and explores immediate regions of the soil. We have developed a new approach to study the dynamics of root meristem distribution in soil, using the relationship between the increase in root length density and the root meristem density. Initiated at the seed, the location of root meristems in barley seedlings was shown to propagate, wave‐like, through the soil, leaving behind a permanent network of roots for the plant to acquire water and nutrients. Data from observations on barley roots were used to construct mathematical models to describe the density of root meristems in space. These models suggested that the morphology of the waves of meristems was a function of specific root developmental processes. The waves of meristems observed in root systems of barley seedlings exploring the soil might represent a more general and fundamental aspect of plant rooting strategies for securing soil resources. 相似文献
86.
An inhibitor in faba bean sap decreased the infectivity of bean yellow mosaic virus in undiluted sap to 0.2% of its potential infectivity calculated from diluted preparations. 相似文献
87.
Insights into the Evolution of Nuclear Dualism in the Ciliates Revealed by Phylogenetic Analysis of rRNA Sequences 总被引:5,自引:0,他引:5
BRIGITTE HAMMERSCHMIDT MARTIN SCHLEGEL DENIS H. LYNN DETLEF D. LEIPE MITCHELL L. SOGIN IGOR B. RAIKOV 《The Journal of eukaryotic microbiology》1996,43(3):225-230
The small subunit rRNA gene sequences of the karyorelictean ciliates, Loxodes striatus and Protocruzia sp., and the heterotrichian ciliates, Climacostomum virens and Eufolliculina uhligi , were used to test the evolution of nuclear dualism in the Phylum Ciliophora. Phylogenies derived using a least squares distance method, neighbour joining, and maximum parsimony demonstrate that the karyorelictean ciliates sensu Small and Lynn, 1985 do not form a monophyletic group. However, Loxodes and the heterotrich ciliates form the first branch in the ciliate lineage, and Protocruzia branches, in distance methods, basal to the spirotrich lineage. It is proposed that Protocruzia be removed from the Class Karyorelictea, and placed in closer taxonomic association with the spirotrich lineage. The distribution of nuclear division types along the phylogenetic tree is consistent with the notion that macronuclei incapable of division represent a derived rather than a primitive or "karyorelictid" character trait. 相似文献
88.
WHITE LL 《Proceedings of the Royal Society of Medicine》1948,41(12):866-868
89.
90.
A study of genetic diversity in Populus nigra subsp. betulifolia in the Upper Severn area of the UK using AFLP markers 总被引:6,自引:0,他引:6
M. O. WINFIELD G. M. ARNOLD F. COOPER M. LE RAY J. WHITE A. KARP & K.J. EDWARDS 《Molecular ecology》1998,7(1):3-10
A survey of amplified fragment length polymorphism (AFLP) was conducted to examine genetic diversity in 146 individuals of British, native black poplar ( Populus nigra subsp. betulifolia ) and three individuals considered by collectors to be non- betulifolia poplars. Using two primer pairs, a total of 147 bands were detected of which 82 (56%) were polymorphic in at least one individual. Cluster analysis and principal coordinates analysis of the calculated similarity matrix revealed a low level of genetic diversity, although a loose clustering into five groups could be identified, one of which contained the non- betulifolia individuals. Examination of the spatial distribution of the other four groups (all betulifolia ) revealed a general correlation between geographic proximity and genetic similarity. On the basis of the polymorphism observed, it was possible to identify a small number of individual plants which exhibit maximum diversity and might therefore be suitable for inclusion in a replanting programme designed to maintain at least the existing low level of polymorphism observed within British black poplar. 相似文献