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31.
Advance planning can facilitate the care of a patient with an exotic disease who is admitted to a hospital that lacks facilities for high-security isolation. The Department of National Health and Welfare contingency plan for dealing with such patients lacks specific information in a number of areas of medical care, as described in this paper. Consideration must be given to the number of personnel trained and readied for employment, the criteria for selection and special preparation. The protective clothing generally used for hospital isolation procedures is inadequate. Several types of special clothing, including a respirator, are available for total protection of personnel; the clothing may be uncomfortable when worn for long periods, and does restrict movement, vision and communication. All persons entering the isolation suite must change into fully protective clothing, and double layers of clothing are required for direct patient care. All personnel must shower and change before leaving the isolation suite. Suitable facilities for dressing and showering, together with entry and exit routines, must be considered. Hand washing, daily cleaning procedures and disposal of liquid and solid wastes all require special procedures. The social and psychologic problems of patients and their families must also be considered. Preplanning is required to decrease the risks involved in monitoring vital signs and implementing emergency procedures requiring contact with the patient''s blood. 相似文献
32.
L C Best M B McGuire T J Martin F E Preston R G Russell 《Biochimica et biophysica acta》1979,583(3):344-351
33.
Triton-solubilized Photosystem I particles from spinach chloroplasts exhibit largely reversible P-700 absorption changes over the temperature range from 4.2 K to room temperature. For anaerobic samples treated with dithionite and neutral red at pH 10 and illuminated during cooling, a brief (1 microseconds) saturating flash produces absorption changes in the long wavelength region that decay in 0.95 +/- 0.2 ms from 4.2 to 50 K. Above 80 K a faster (100 +/- 30 microseconds) component dominates in the decay process, but this disappears again above about 180 K. The major decay at temperatures above 200 K occurs in about 1 ms. The difference spectrum of these absorption changes between 500 and 900 nm closely resembles that of P-700. Using ascorbate and 2.6-dichlorophenolindophenol as the reducing system with a sample of Photosystem I particles cooled in darkness to 4.2 K, a fully reversible signal is seen upon both the first and subsequent flashes. The decay time in this case is 0.9 +/- 0.3 ms. 相似文献
34.
Absorption changes (ΔA) at 820 nm, following laser flash excitation of spinach chloroplasts and Chlorella cells, were studied in order to obtain information on the reduction time of the photooxidized primary donor of Photosystem II at physiological temperatures.In the microsecond time range the difference spectrum of ΔA between 750 and 900 nm represents a peak at 820 nm, attributable to a radical-cation of chlorophyll a. In untreated dark-adapted material the signal can be attributed solely to P+?700; it decays in a polyphasic manner with half-times of 17 μs, 210 μs and over 1 ms. The oxidized primary donor of Photosystem II (P+II) is not detected with a time resolution of 3 μs. After treatment with 3–10 mM hydroxylamine, which inhibits the donor side of Photosystem II, P+II is observed and decays biphasically (a major phase with , and a minor phase with ), probably by reduction by an accessory electron donor.In the nanosecond range, which was made accessible by a new fast-response flash photometer operating at 820 nm, it was found the P+II is reduced with a half-time of 25–45 ns in untreated dark-adapted chloroplasts. It is assumed that the normal secondary electron donor is responsible for this fast reduction. 相似文献
35.
Growth and nitrate reductase activity were measured in Paul's Scarlet rose cell suspensions, cultured in media purified from molybdenum and containing nitrate or urea as sole nitrogen source with or without added Mo. Urea could replace nitrate to yield 80% of the fresh weight in nitrate medium. Nitrate reductase activities were compared by in vivo and in vitro assays. The latter varied due to inactivation during extraction. Compared with activities in cells in complete NO3
- medium, activity in NO3
--Mo cells was reduced to 30% and, in urea-grown cells, to trace amounts. Increases in nitrate reductase activity were found when NO3
- alone was added to NO3
- or urea+Mo cultures. In NO3
--Mo cultures, Mo alone or with NO3
- caused a similar increase in activity, whereas urea-Mo cultures required both NO3
- and Mo for enzyme induction.Abbreviations FAD
flavin adenine dinucleotide
- Mo
molybdenum
- NADH
reduced nicotinamide adenine dinucleotide
- NO3
-+Mo
standard MX1 culture medium
- NO3
--Mo
MX1 medium purified of Mo and used for continuous subculture with nitrate
- NR
nitrate reductase
- PSR
Paul's Scarlet rose
- PVP
polyvinylpyrrolidone
- U
urea
- U+Mo
MX1 medium containing urea instead of nitrate
- U-Mo
MX1 medium containing urea instead of nitrate and also purified of Mo 相似文献
36.
37.
Effect of temperature on the integrity of Bacillus psychrophilus cell walls 总被引:3,自引:1,他引:2
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Cell walls isolated from Bacillus psychrophilus autolyse at temperatures which support growth. At temperatures above the maximum growth temperature (28 C), a nonenzymatic lysis occurs. Removal of autolytic enzyme activity with 10 m LiCl had little effect on the rate or extent of lysis at elevated temperatures (37 and 45 C). Nonenzymatic lysis was characterized chemically by a decrease in the liberation of N-terminal groups, and the effects of pH, Ca(2+), and ethylenediaminetetraacetic acid suggest that ionic linkages are involved in much of the integrity of the cell wall of this psychrophile. The nonenzymatic absorbance decrease at 45 C can be reversed to the extent of 70 to 100% at 0 C. Centrifugation of a heat-lysed wall suspension separated a soluble protein component which is required for low-temperature reaggregation. Preliminary evidence indicates the insoluble residue which remains after temperature-mediated lysis is primarily peptidoglycan. 相似文献
38.
Chen Tzu Yu Hale John D. F. Tagg John R. Jain Rohit Voss Abigail L. Mills Nikki Best Emma J. Stevenson Duncan S. Bird Philip A. Walls Tony 《Probiotics and antimicrobial proteins》2021,13(3):734-738
Otitis media is a common childhood infection, frequently requiring antibiotics. With high rates of antibiotic prescribing and increasing antibiotic resistance, new strategies in otitis media prevention and treatment are needed. The aim of this study was to assess the in vitro inhibitory activity Streptococcus salivarius BLIS K12 against otitis media pathogens. Efficacy of the bacteriocin activity of S. salivarius BLIS K12 against the otitis media isolates was assessed using the deferred antagonism test. Overall, 48% of pathogenic isolates exhibited some growth inhibition by S. salivarius BLIS K12. S. salivarius BLIS K12 can inhibit the in vitro growth of the most common pathogens.
相似文献39.
Field studies of community assembly patterns increasingly use phylogenetic relatedness as a surrogate for traits. Recent experiments appear to validate this approach by showing effects of correlated trait and phylogenetic distances on coexistence. However, traits governing resource use in animals are often labile. To test whether feeding trait or phylogenetic diversity can predict competition and production in communities of grazing amphipods, we manipulated both types of diversity independently in mesocosms. We found that increasing the feeding trait diversity of the community increased the number of species coexisting, reduced dominance and changed food availability. In contrast, phylogenetic diversity had no effect, suggesting that whatever additional ecological information it represents was not relevant in this context. Although community phylogenetic structure in the field may result from multiple traits with potential for phylogenetic signal, phylogenetic effects on species interactions in controlled experiments may depend on the lability of fewer key traits. 相似文献
40.
Kendall L. Simon David A. Best James G. Sikarskie H. Tyler Pittman William W. Bowerman Thomas M. Cooley Scott Stolz 《The Journal of wildlife management》2020,84(3):553-561
As bald eagle populations recover, defining major sources of mortality provides managers important information to develop management plans and mitigation efforts. We obtained data from necropsies on 1,490 dead bald eagles (Haliaeetus leucocephalus) collected in Michigan, USA, conducted from 1986 to 2017 to determine causes of death (COD). Trauma and poisoning were the most common primary COD categories, followed by disease. Within trauma and poisoning, vehicular trauma (n = 532) and lead poisoning (n = 176) were the leading COD subcategories, respectively. Females comprised a greater number of carcasses for most COD diagnoses. The proportion of trauma and poisoning CODs significantly increased in the last few years of the study in comparison to a select few years at the beginning. Trauma CODs were greater in autumn months during whitetail deer (Odocoileus virginianus) breeding and hunting seasons and in February, when aquatic foraging is unavailable and eagles are likely forced to scavenge along roadsides. Poisoning CODs were greatest in late winter and early spring months, when deer carcasses containing lead ammunition, which are preserved by the cold weather, also become a supplemental food source. The major infectious disease CODs, West Nile virus and botulism (Clostridium botulinum type E), were more prevalent during summer months. We recommend moving road-killed carcasses, especially white-tailed deer, from the main thoroughfare to the back of the right-of-way, and the transition from lead ammunition and fishing tackle to non-toxic alternatives to decrease these main anthropogenic sources of mortality for bald eagles, and other scavenger species. © 2020 The Wildlife Society. 相似文献