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31.
Michael J. Hall Louis J. Nisbet Donald Westmacott Philippe Wong-Kai-In 《Journal of microbiological methods》1984,2(4):203-214
Roche Susceptibility Test (RST) Medium represents the most completely optimized and convenient fully defined medium described. It requires no post-autoclaving supplementation with vitamins, supports good growth of all common aerobic and anaerobic pathogens and may be used as a broth or agar gel on which the swarming of Proteus spp. is virtually eliminated. The broth as a superior buffering capacity to most complex media and an osmolality and pH close to those of human serum. RST is highly satisfactory for the susceptibility testing of commonly used antibiotics and meets the requirements of the National Committe for Clinical Laboratory Standards of the U.S.A. in almost every respect. 相似文献
32.
R. Van Potter Theresa Ruh Evanson Debra P. Gayda James A. Gurr 《In vitro cellular & developmental biology. Plant》1984,20(9):723-731
Summary The induction and decay of ornithine decarboxylase (ODC) by insulin and asparagine in cultures of H4-II-EC3 (H35) hepatoma
cells was studied in a modified Waymouth medium in the presence of fetal bovine serum (FBS) and in serum-free media. The insulin
response was enhanced by the presence of asparagine although the effect of asparagine was not so much on the initial increase
as it was on a slowing of the decline after the maximum was reached at 6 to 8 h after the supplements were added together
with fresh medium. In all cases the initial ODC activity was zero at zero time for addition of media and supplements, and,
after reaching the maximum, activity declined to near zero by 24 h. Fetal bovine serum gave induction that followed a similar
time course but was inferior to the combintion, of insulin plus asparagine and, in fact, FBS inhibited the latter response.
Putrescine (the product formed from ornithine by ODC), at 10−5
M, markedly inhibited the induction of ODC by insulin or FBS, but the inhibition was less when asparagine was present.
This work was supported in part by Grants CA-07175, CA-22484, and CA-17334 from the National Cancer Institute. D. P. G. is
a Predoctoral Fellow at the Food Research Institute, supported by a fellowship from the Monsanto Fund and by NIH Grant R01-AI
15693 to Prof. Michael W. Pariza, Food Research Institute, University of Wisconsin, Madison. 相似文献
33.
R. H. Goodwin G. J. Tompkins P. McCawley 《In vitro cellular & developmental biology. Plant》1978,14(6):485-494
Summary A series of cell lines unique in insect virus susceptibility pattern have been isolated from the ovaries of the gypsy moth
(Lymantria dispar: Lepidoptera: Lymantriidae) on a synthetic medium with mammalian and avian serum supplementation. Growth curves showed the
poorest growth occurring on peptone-based media with somewhat better growth on amino-acid-based media. The best growth was
obtained with combined media. Serological study distinguished the present cell lines from one another and from cell lines
derived from other insect species grown routinely in the same laboratory. Baculovirus susceptibility among the new lines varied
from no response to a specific complete replication response upon challenge by the homologous (gypsy moth) nuclear polyhedrosis
virus.
This research was funded in part through a reimbursable agreement with the U.S. Forest Service. 相似文献
34.
Hans R. Gislerød 《Plant and Soil》1982,69(3):445-456
Summary The air content in three types of propagation media, Jiffy-7 and Jiffy-9 which are Sphagnum peat and Grodan which is rockwool,
were investigated when they were held at moisture tensions of 0,6 and 12 cm measured from the base of the media. At 0 cm tension
the air content (vol. %) was highest in Jiffy-9 and lowest in Jiffy-7. At 12 cm tension the air content was higher in Grodan
than in Jiffy-9 and Jiffy-7.
Oxygen diffusion coefficients (ODC) and oxygen diffusion rates (ODR) were measured at the different air contents. At air contents
below 20 vol. % ODC was about the same for Jiffy-9 and Grodan but at air contents above 20 vol.% it was larger for Jiffy-9
than for Grodan. The oxygen diffusion rate was measured at 0, 4 and 8 cm moisture tension. At all tensions it was approximately
20% higher in Jiffy-9 than in Grodan and Jiffy-7. The ODR in Jiffy-7 and Grodan were affected equally at the same tension,
although Grodan contained more air.
Report no 253 相似文献
35.
The inorganic formulations of fourteen common plant tissue culture basal media were examined from the primary literature. Inaccuracies and errors were found for molecular formulae, chemical hydrations, and molar equivalences for iron/EDTA complexation. A comparison with published basal medium formulations from six commercial suppliers uncovered additional inaccuracies, modifications, and errors, thereby emphasizing the need for investigators to examine and describe medium formulations precisely in future publications. 相似文献
36.
The relationship between numbers of Deroceras reticulatum and the establishment of ryegrass cv. Melle and white clover cv. Milkanova was studied on a mini-plot experiment. Assessments 12 and 33 days after sowing showed that Deroceras reticulatum had a proportionally greater impact on survival and growth of clover than on ryegrass. Slugs had no apparent effect on numbers or growth of three species of broad-leaved weeds (Senecio vulgaris, Cardamine hirsuta and Epilobium sp.) which occurred in the field experiment. In pot experiments where seedlings of ryegrass together with one of three clover cultivars, with or without chickweed (Stellaria media), were exposed to Deroceras reticulatum, seedlings of white clover cv. Aran were less affected by slug grazing than cvs S184 or Milkanova. The presence of different clover cultivars did not significantly influence the impact of slugs on growth of ryegrass or chickweed, nor did the presence or absence of chickweed influence the effect of slugs on ryegrass and clover seedlings. Slugs had less impact on the growth of chickweed than on ryegrass or clover. Thus slug grazing would make clover less able to compete with chickweed as well as the other weeds found in the mini-plot experiment. 相似文献
37.
Hybridomas lend themselves particularly well to large scale cultivation techniques since they grow as single cells in suspension without requiring attachment to a substrate. Furthermore, many cell strains have been adapted to grow in serum-free (SF) media to a similar cell density and antibody production as in serum containing media. This review will concern itself mainly with the cultivation of hybridomas in SF-media in bioreactors of various types with the ultimate goal of producing large quantities of monoclonal antibodies (mAb). 相似文献
38.
Abstract: A frozen mixture of solubilized brain proteolipid proteins in chloroform-methanol is not sublimable in a vacuum. However, when 7 to 10 volumes of benzene were added to a chloroform-methanol solution containing 5 mg of proteolipid protein per ml, the proteolipid proteins remained in solution for a while and the frozen mixture was easily sublimated at 2 mm Hg. Before the addition of benzene, higher concentrations of protein required the acidification of the medium to avoid precipitation of proteolipid proteins. In contrast to what happens when proteolipid proteins are obtained by the evaporation of the organic mixture at room temperature, the protein obtained by lyophilization was soluble in aqueous solutions of ionic and nonionic detergents. Sodium dodecyl sulfate at 0.6 to 0.7% concentration completely solubilized the proteolipid protein obtained by lyophilization. With the nonionic detergents Lubrol WX and Triton X-100, a solubilization between 50 and 65% was achieved. Sodium deoxycholate was practically ineffective. Triton X-100 showed selectivity in solubilizing certain proteins. The role of lipids in the solubilization of proteolipid proteins with detergents is discussed. 相似文献
39.
A. Ayanaba 《Plant and Soil》1981,60(1):157-159
Summary Routine media containing 0.005% each of benomyl and mancozeb for the enumeration and isolation of Azotobacter and Beijerinckia
in soil studies are described. The incorporation of these fungicides in routine media was found to be more effective in inhibiting
fungal contaminants than the use of cycloheximide. 相似文献
40.