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991.
992.
Summary In view of the interest in high productivity fermentations at increased temperatures, the effect of temperature on the kinetics of ethanol production by Saccharomyces uvarum was investigated in the range 25–43°C. Using a mathematical model and a nonlinear computer simulation package, the kinetic parameters at each temperature were estimated. It was found that the optimal temperature for growth was 34°C, while the specific ethanol production rate was maximal at 37–43°C. Up to 37°C, the inhibitory effects of ethanol on growth and specific ethanol production rate were unaffected by temperature. However, above this temperature, ethanol inhibition increased significantly. 相似文献
993.
994.
A simple, quick procedure for the isolation of pig kidney d-amino acid oxidase [EC 1.4.3.3; d-amino acid:oxygen oxidoreductase (deaminating)] is described based upon the use of granulated hydroxylapatite for chromatography. The purity appears to be comparable to that obtained by other procedures. The holoenzyme was isolated as the benzoate complex. 相似文献
995.
Sensitization of guinea pigs to herpes simplex virus 总被引:3,自引:0,他引:3
996.
997.
998.
Surveillance of arthropod vector-borne infectious diseases using remote sensing techniques: a review
Epidemiologists are adopting new remote sensing techniques to study a variety of vector-borne diseases. Associations between satellite-derived environmental variables such as temperature, humidity, and land cover type and vector density are used to identify and characterize vector habitats. The convergence of factors such as the availability of multi-temporal satellite data and georeferenced epidemiological data, collaboration between remote sensing scientists and biologists, and the availability of sophisticated, statistical geographic information system and image processing algorithms in a desktop environment creates a fertile research environment. The use of remote sensing techniques to map vector-borne diseases has evolved significantly over the past 25 years. In this paper, we review the status of remote sensing studies of arthropod vector-borne diseases due to mosquitoes, ticks, blackflies, tsetse flies, and sandflies, which are responsible for the majority of vector-borne diseases in the world. Examples of simple image classification techniques that associate land use and land cover types with vector habitats, as well as complex statistical models that link satellite-derived multi-temporal meteorological observations with vector biology and abundance, are discussed here. Future improvements in remote sensing applications in epidemiology are also discussed. 相似文献
999.
1000.
There is relatively little known about the supply for allograft tissues in Canada. The major aim of this study is to quantify
the current or “Known Supply” of human allograft tissue (bone, tendons, soft tissue, cardiovascular, ocular and skin) from
known tissue banks in Canada, to estimate the “Unknown Supply” of human allograft tissue available to Canadian users from
other sources, and to investigate the nature and source of these tissue products. Two surveys were developed; one for tissue
banks processing one or more tissue types and the other specific to eye banks. Thirty nine sites were initially identified
as potential tissue bank respondent sites. Of the 39 sites, 29 sites indicated that they were interested in participating
or would consider completing the survey. A survey package and a self-addressed courier envelope were couriered to each of
29 sites. A three week response time was indicated. The project consultants conducted telephone and email follow-up for incomplete
data. Unknown supply was estimated by 5 methods. Twenty-eight of 29 sites (97%) completed and returned surveys. Over the past
year, respondents reported a total of 5,691 donors (1,550 living and 4,141 cadaveric donors). Including cancellous ground
bone, there were 10,729 tissue products produced by the respondent banks. Of these, 71% were produced by accredited banks
and 32% were ocular tissues. Total predicted shortfall of allograft tissues was 31,860–66,481 grafts. Through estimating Current
supply, and compiling additional qualitative information, this study has provided a snapshot of the current Canadian supply
and shortfall of allograft tissue grafts. 相似文献