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91.
May, Lewis K. (Woman's Medical College of Pennsylvania, Philadelphia), Ralph A. Knight, and H. William Harris. Allescheria boydii and Aspergillus fumigatus skin test antigens. J. Bacteriol. 91:2155-2157. 1966.-Protein and polysaccharide fractions were extracted from culture filtrates of Allescheria boydii and Aspergillus fumigatus by the methods of Seibert and of Heidelberger, and injected intradermally into guinea pigs previously infected with these fungi. The diameter of erythema and induration was determined at 8, 24, and 48 hr. The protein and polysaccharide antigens yielded specific skin reactions in homologously infected guinea pigs. Erythema appeared at 8 hr with both the protein and polysaccharide antigens. At this time, the polysaccharide skin tests showed erythema and a central blanched wheal. A similar wheal was not observed with the protein. The erythema of the polysaccharide reaction began fading at 24 hr, whereas the protein reaction remained unchanged through 48 hr with both antigens. In guinea pigs, the area of erythema was more constant and thus easier to measure than was induration. 相似文献
92.
93.
Tariq Ahmad Joanne C. Conover Martin M. Quigley Robert L. Collins Anthony J. Thomas Ralph B. L. Gwatkin 《Molecular reproduction and development》1989,22(4):369-373
Failure of epididymal spermatozoa from T/t mutant mice, but not from t/t individuals, to fertilize oocytes in vitro was partially overcome by opening a small aperture in the zona pellucida with acidified Tyrode's solution to permit direct access of the spermatozoon to the vitellus. This study provides a model system to evaluate requirements for successful zona drilling in the treatment of human infertility and further insights into the effects of the t complex on sperm fertility. 相似文献
94.
A simple,rapid protocol for adventitious shoot development from mature cotyledons of glycine max cv bragg 总被引:5,自引:0,他引:5
Seth Mante Ralph Scorza John Cordts 《In vitro cellular & developmental biology. Plant》1989,25(4):385-388
Mature soybean cotyledons (Maturity group VII) were cultured on modified MS containing 0–2.5 μM indole-butyric acid (IBA);
0–10 μM 6-benzylaminopurine (BAP) and 0.7% agar. Embryonic axes of explants were removed prior to culture initiation and cultures
were incubated at 24°C with 45–50 μE. s−1.M−2 of mixed irradiance with 16 h photoperiod. Shoot proliferation occurred at 0–2.5 μM IBA and 5–10 μM BAP, while in the presence
of 2.5 μM IBA alone, only roots developed. Abnormal shoots were produced with 2.5 μM IBA and 5–7.5 μM thidiazuron. Adventitious
shoot development started 7–14 d after culture initiation in the region where the embryonic axis was previously attached to
the cotyledon and shoots were visible within 28 days. The presence of the embryonic axis inhibited shoot morphogenesis. The
shoots were rooted on half strength MS inorganic salts plus vitamins, 2% sucrose, 0.5 μM NAA acid or 2.5–5 μM IBA, or 5–10
μM IAA, and 0.7% agar. Rooted plants were acclimatized under a mist in the greenhouse. This simple, rapid,in vitro adventitious shoot development protocol could be adapted for transformation/regeneration studies in soybean.
Trade and company names are used in the publication solely to provide specific information. Mention of a trade or company
name does not constitute a warranty or an endorsement by the U.S. Department of Agriculture to the exclusion of other products
or organizations not mentioned. 相似文献
95.
Summary The protein sequences of seven 3-aminoglycoside phosphotransferases falling into the six identified types and three 6-aminoglycoside phosphotransferases were analyzed to give a rooted phylogenetic tree. This tree supports the origin of these groups of enzymes in an ancestor closely related to the actinomycetes, and that horizontal transfer of the resistance genes occurred, possibly via transposons. The implications for genetic engineering of a novel antibiotic are discussed. 相似文献
96.
Gary W. Arendash William J. Millard Ralph Dawson Jr. Adrian J. Dunn Edwin M. Meyer 《Neurochemical research》1989,14(11):1113-1118
Young adult rats received either unilateral or bilateral ibotenic acid infusions in their nucleus basalis, destroying most of the cholinesterase-staining neurons in that region. Cerebral cortex levels of choline acetyltransferase, somatostatin, neuropeptide Y, and monoamines were then assayed 2.5 and 10 months after bilateral lesions, or, 2.5, 10, and 14 months after unilateral lesions. Entorhinal and cerebral cortex levels of several amino acid transmitters were also measured. As expected, choline acetyltransferase activity was decreased in the frontal cortex ipsilateral to the ibotenic acid infusion in unilaterally or bilaterally lesioned animals. Parietal cortex concentrations of somatostatin and neuropeptide Y were altered by lesioning in a complicated, time-dependent manner. Thus, while unilateral lesions transiently decreased or had no effect on these neuropeptide levels, bilateral lesions elevated the level of each neuropeptide by over 100% at 10 months. Other cortical transmitter systems investigated appeared to be less affected by nucleus basalis-lesions. Unilateral lesions had no effect on prefrontal cortex norepinephrine, serotonin, or dopamine content at 14 months post-lesioning. These different neurochemical effects of unilateral and bilateral nucleus basalis lesions may be important for developing a model for the trans-synaptic effects of cortical cholinergic deafferentation. 相似文献
97.
J Didsbury R F Weber G M Bokoch T Evans R Snyderman 《The Journal of biological chemistry》1989,264(28):16378-16382
98.
J M Wang Z G Chen G J Cianciolo R Snyderman F Breviario E Dejana A Mantovani 《Journal of immunology (Baltimore, Md. : 1950)》1989,142(6):2012-2017
The effects of IL-1 on vascular endothelium result in a complex set of alterations which are potentially disruptive of vessel wall and underlying tissue integrity. The present study was aimed at investigating possible regulation of such potentially destructive responses elicited by IL-1 on endothelial cells. Culture supernatants of IL-1-treated human umbilical vein endothelial cells (HEC) were depleted of retroviral p15E-related Ag with immobilized anti-p15E mAb. The monocyte chemotactic and polarizing activity of supernatants of IL-1-treated HEC (presumably related to colony-stimulating factors being released by HEC) was markedly augmented by absorption on immobilized anti-p15E antibodies. Irrelevant IgG had no effect and anti-p15E antibodies did not affect the chemotactic activity of supernatants from unstimulated HEC. The material eluted from Sepharose-bound anti-p15E antibodies was devoid of chemotactic and polarizing activity and suppressed the polarization and migration of monocytes in response to chemoattractants. The alpha and beta molecular species of IL-1 were equally effective in inducing the production of p15E-related inhibitor. The production of a p15E-related inhibitor of chemotaxis induced by IL-1 in HEC may represent a negative signal in the regulation of the potentially destructive responses to pro-inflammatory cytokines. 相似文献
99.
100.
Abstract. The Clements' Deterministic model of plant communities implies that a change in one species, especially a change in the physiognomic dominant, would have profound effects on the remainder of the community. Gleason's Individualistic model suggests there would be little effect. These alternative models are tested by examining the forest composition on both sides of a boundary along which the tree Nothofagus menziesii is slowly invading. Classification of forest composition, excluding N. menziesii, gave little evidence of an effect of N. menziesii on the lower strata: understorey vegetation types were distributed across the boundary. Some differences were found at individual sites, but these were often inconsistent between sites. Ordination, also excluding N. menziesii, similarly showed that none of the first three understorey axes reflected any effect of N. menziesii. The fourth axis was correlated with the presence of N. menziesii, but only when canopy trees were included. It is concluded that specific composition of the canopy in these montane New Zealand evergreen forests has little effect on the understorey, supporting Gleason's Individualistic concept of the community. 相似文献