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71.
Gases are transparent and the piping layout in anesthesia machines is not obvious, making it hard to understand anesthesia machine function, potential failure modes, and recovery from faults. We experimented with an approach that simplified the layout of the anesthesia machine piping by removing extraneous details and making gases not only visible, but also color-coded. More than 15 anesthesia machine controls were represented by icons that a user can adjust by clicking on the icon with a pointing device and subsequently observing the effect of his/her intervention on anesthesia machine function in real time. We simulated two anesthesia machine failures and also supported non-English languages and non-US gas color codes. Further, we initiated an experiment in Web philanthropy by deliberately choosing to make the educational module accessible without charge and selected the Web as the preferred medium for dissemination of the Virtual Anesthesia Machine (VAM) viewable at http://www.anest.ufl.edu/vam . Originally designed for use in human anesthesiology, a significant percentage (about 30%) of the 54 000 international visitors, as tracked by an independent third-party Web traffic monitoring service, for the period 9/00–5/02, were from the veterinary field. VAM is being used as part of the curriculum in veterinary programs in the US and overseas and has been well received by the global anesthesia community (human and veterinary).  相似文献   
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73.
Decreased proportion of CD4+ and CD8+ T lymphocytes in peripheral blood likely contributed to susceptibility to Pneumocystis carinii in a foal. Cytological evaluation of bronchoalveolar lavage was required for identification of the pathogen and serial flow-cytometric analysis of peripheral blood lymphocytes documented transient low expression of CD4+ and CD8+ T lymphocytes. Although immunodeficiency is uncommon, it must be included in the differential diagnosis for patients suffering from chronic or opportunistic infections and may provide an indication for immunostimulant therapy.  相似文献   
74.
Insulin is a pancreatic hormone that classically regulates carbohydrate and fat metabolism, but also appears to play a role in various reproductive processes. A preliminary study suggested insulin production by day 10 to 18 equine conceptuses. The aim of the present study was to examine the hypothesis that insulin is the conceptus signal responsible for maternal recognition of pregnancy (MRP) in the mare, or otherwise influences reproductive cyclicity during the MRP period. Six Warmblood mares were treated daily during days 7 to 17 after ovulation of two successive oestrous cycles with either (short and intermediate acting) insulin or control saline. Mares were assigned randomly to treatment, and crossed over during the subsequent cycle. Time of ovulation and corpus luteum surface area were determined by serial transrectal ultrasonographic examination of the mares' ovaries, and daily jugular vein blood samples were analysed for progesterone and luteinizing hormone (LH) concentrations. On day 14 of dioestrus, the luteolytic drive was examined by measuring systemic 15-ketodihydroprostaglandin F2 α (PG-metabolite) release in response to oxytocin challenge. In addition, yolk sac fluid recovered from 32 day 10 to 14 equine conceptuses was analysed for insulin concentrations. Insulin administration did not affect luteal size, dioestrus length, the interovulatory interval, or circulating LH concentrations. Insulin administration also failed to suppress oxytocin-induced PGF2 α release, and tended to depress systemic progesterone concentrations. Finally, insulin could not be detected in the yolk sac fluid of day 10 to 14 equine conceptuses by radio-immunoassay. It is concluded that insulin administered daily during days 7 to 17 of dioestrus has little or no effect on reproductive cyclicity in the mare, and is unlikely to be the MRP signal.  相似文献   
75.
冬季日光温室的保温措施及对天气性灾害的预防对策   总被引:1,自引:0,他引:1  
高效节能日光温室以太阳能为主要能源 ,不加温或临时加温就能进行果菜类生产 ,但近几年发展的温室偏高偏宽 ,保温措施又跟不上 ,结果在1 999年冬至 2 0 0 0年春雪多、严寒的条件下 ,不少温室出现了 2℃以下低温 ,甚至冻害 ,使果菜类生产受到很大影响 ,造成了很大的损失。对此 ,我站经过试验和调研 ,提出如下的保温措施及对天气灾害性的对策 ,使果菜类冬季能在日光温室得以正常生长 ,进一步提高冬季蔬菜生产的经济效益和社会效益 ,保证我市保护地蔬菜生产持续发展。1 温室结构与保温的关系沈阳市地处北纬 41°以北 ,冬至太阳高度角低 ,中午 …  相似文献   
76.

Purpose

Acute whole-sediment bioassay with the estuarine and marine amphipod Corophium volutator (Pallas) is widely used to assess toxicity of sediments. According to the guidelines DIN EN ISO 16712, mortality is the determined toxic endpoint. Additionally, the reburrowing ability of the surviving organisms of this acute toxicity test in fresh uncontaminated sediment is suggested as the sublethal endpoint, but insufficient information (e.g., exact measurement protocols) on this endpoint is provided, thus confounding factors and the interpretation of the results. The aim of this study was to provide information on burrowing activity as a sublethal endpoint.

Materials and methods

Amphipod tests were carried out in the laboratory, and the burrowing behavior was examined in a size- and gender-specific manner. For sediment testing, only animals of the same size were used in a defined sex ratio because it was found that female animals buried themselves faster than males and that smaller animals burrowed faster than bigger organisms. Statistical analyses were applied to determine whether burrowing time and ability differ significantly between sexes and sizes. Finally, tests were run to discern whether the burrowing ability could be a more sensitive endpoint than mortality.

Results and discussion

When the burrowing ability was examined in toxicity tests with contaminated sediment, the test organisms were affected in a dose-dependent manner. With rising concentrations of the contaminated sediment in a sublethal testing following the sediment exposure over 10 days, fewer animals buried themselves into the sediment.

Conclusions

The burrowing behavior can be used as an additional endpoint. For the tested sediment, burrowing was found to be more sensitive than the mortality. Guidance on the measurement protocol for this additional endpoint was developed. Under the test conditions examined, burrowing ability is an appropriate sublethal endpoint to supplement the toxicity test procedure.  相似文献   
77.
78.
Fullerene pipes   总被引:10,自引:0,他引:10  
Single-wall fullerene nanotubes were converted from nearly endless, highly tangled ropes into short, open-ended pipes that behave as individual macromolecules. Raw nanotube material was purified in large batches, and the ropes were cut into 100- to 300-nanometer lengths. The resulting pieces formed a stable colloidal suspension in water with the help of surfactants. These suspensions permit a variety of manipulations, such as sorting by length, derivatization, and tethering to gold surfaces.  相似文献   
79.
Strong infrared circular polarization resulting from dust scattering in reflection nebulae in the Orion OMC-1 star-formation region has been observed. Circular polarization at shorter wavelengths might have been important in inducing chiral asymmetry in interstellar organic molecules that could be subsequently delivered to the early Earth by comets, interplanetary dust particles, or meteors. This could account for the excess of L-amino acids found in the Murchison meteorite and could explain the origin of the homochirality of biological molecules.  相似文献   
80.
Coccidial oocysts and/or vegetative germs, spores, and toxins of Cl. perfringens Type A were used in mono-infection and poly-infection experiments on SPF chicken aged seven and 56 days and kept under different conditions. Necrotic enteritis was regularly reproduced in all experimental groups with polyinfections. In chicken aged seven days necrotic enteritis was reproduced even after repeated mono-infections with 4 X 10(9) gerus and toxin of Cl. perfringens. The loss figures recorded from ground-kept infected groups were higher than those established from the cage-kept animals. The pathologica-anatomic findings recorded from the dead chicken included necrotic, ulcerative, and catarrhal to haemorrhagic intestinal inflammations, with necrotic enteritis being most strongly pronounced in the ileum and jejunum. All infected groups lost not only animals but weight as well. Their average weight on the 21 st day from the onset of infection was up to 26.4 per cent lower than that of the control groups.  相似文献   
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