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1.
  • 1.1. Translating results from low hierarchical levels to higher orders meets with difficulties with respect to temporal, spatial and organizational scales.
  • 2.2. Translating stress effects through hierarchical levels has not yet been possible, thus hampering ecological risk assessment.
  • 3.3. Three approaches to link the various levels are described; the energetics, the endpoint and the minimal structure approach.
  • 4.4. A concept to integrate these approaches to enable extrapolation of stress effects across hierarchical levels is described.
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2.
  • 1.1. Mathematical models can be most helpful in attempts to understand the way effects of toxic substances show up under various conditions. They are essential for extrapolation and prediction, especially when effects have to be quantified.
  • 2.2. In some cases, there is a tight relationship between effects and toxicokinetics, i.e. uptake/elimination behaviour of compounds.
  • 3.3. It can be shown that, at least for some compounds, the toxicokinetics depends on feeding conditions. This alone makes it necessary to account for energetics in the use of laboratory observations for predictions and interpretation concerning field data.
  • 4.4. It can also be shown that, given certain effects on individuals, the consequences for populations depend sensitively on energetics. This leads to an even tighter link between ecotoxicology and energetics.
  • 5.5. A basic problem is that realistic models involve a relatively large number of parameters, even under the most simple assumptions about kinetics and effects. This constraints possibilities for extrapolation and prediction.
  • 6.6. All in all, a close link between experimental and modelling programmes is necessary.
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3.
  • 1.1. The effects of injected catecholamines and their analogues on odour learning in honey bees is described.
  • 2.2. Dopamine blocks the retrieval of a learned odour signal with a specific time course and does not block the storage of this signal.
  • 3.3. Noradrenaline blocks retrieval and storage of a conditioned odour signal.
  • 4.4. Amphetamine shows the same effects as noradrenaline.
  • 5.5. Haloperidol has no affect on memory retrieval or storage.
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4.
  • 1.1. A brief review of development of ideas of the antioxidant activity of carnosine and related compounds is presented.
  • 2.2. An analysis of the behaviour of carnosine in different models of free radical chain reactions shows that carnosine is a potent hydrophylic antioxidant of a direct non-enzymatic action.
  • 3.3. It is characteristic of the higher activity of interaction with active hydroxyl radical.
  • 4.4. However the known biological effects of carnosine cannot be explained only by its anti-oxidant properties.
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5.
Company news     
Including information on:
  • ScanSoft
  • SpeechWorks International
  • Viisage Technology
  • Firstec
  • BIO-key International
  • HP
  • ZN Vision Technologies
  • Unisys
  • US Government’s
  • Communication Intelligence Corporation
  • Infinity Technologies
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6.
Company news     
  • Daon
  • Musicrypt
  • EMI Music Canada
  • Digital Broadband Networks
  • FaceKey Corporation
  • Eystar Media Inc (EMI)
  • Temasya Wira
  • Animated Electronic Industries
  • BIO-key International
  • Entryport Corporation
  相似文献   

7.
Application news     
Including information on:
  • Martin State Airport
  • Bioscrypt
  • Saflink
  • Office of the Secretary of Defense
  • Department of Defense
  • Boeing Corporation
  • Bell ID, Gemplus
  • Siemens
  • Foreign Ministry
  相似文献   

8.
  • 1.1. In this study, expression of a 60-kDa heat shock protein in rat pancreas was investigated before and after water-immersion stress, which has been known as an exacerbation factor of caerulein-induced pancreatitis in rats, by Western blot.
  • 2.2. A 60-kDa heat shock protein increased after water-immersion stress in both soluble and insoluble fractions of the pancreas.
  • 3.3. Serum amylase level and pancreas weight did not increase after water-immersion.
  • 4.4. No pathologic alteration was observed in the pancreas after water-immersion.
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9.
In brief     
  • Bioscrypt
  • Saflink
  • Dell
  • Fujitsu Microelectronics America
  • Identix
  • Viisage
  • Acsys Biometrics
  • US Government
  相似文献   

10.
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Highlights
  • •Changes to the proteome of skin fibroblasts subjected to reductive stress have been quantitated.
  • •Only a small set of proteins is selectively diminished upon exposure to reductants.
  • •Collagens (COL1A2 and COL6A2) emerge as sentinels of reductive stress.
  • •Reductive stress triggers receptor-independent Akt phosphorylation at Ser473.
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11.
  • 1.1. To assess whether the stretch-activated (SA) channels in snail cells could contribute to osmoregulation, information is needed about the behaviour of the cells under anisosmotic conditions.
  • 2.2. Cells of Lymnaea stagnalis were therefore examined during acute hyposmotic stress (HOS).
  • 3.3. Kidney, heart and neuronal cells (monitored photographically) swelled less than expected for strictly semipermeable cells, but exhibited no regulatory volume decrease.
  • 4.4. Long-term viability of the cells was not compromised following acute hyposmotic stress.
  • 5.5. Quinidine, which blocks SA channels in Lymnaea, intensified stress-induced swelling most markedly in kidney cells.
  • 6.6. The data can, however, be explained without invoking recruitment of SA channels.
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12.
  • 1.1. A quick and simple procedure is described for purifying kallikrein from human whole saliva. The enzyme has been purified about 2700-fold with a yield of approx. 30%.
  • 2.2. The procedure is based on the immediate fractionation of saliva by ion exchange chromatography. This is followed by a combination of affinity and high performance liquid chromatography.
  • 3.3. The results indicate that another protein component binds to the enzyme at pH 8.0.
  • 4.4. The homogeneity of the enzyme has been demonstrated by gel electrophoresis in the absence as well as in the presence of sodium dodecylsulfate.
  • 5.5. A mol. wt of 40,100±1800 has been calculated from gel electrophores is experiments.
  • 6.6. Sedimentation equilibrium in an analytical ultracentrifuge gave a mol. wt of 39,700.
  • 7.7. The amino acid composition has been determined and it confirms that the enzyme has a low isoelectric point.
  • 8.8. The presence of tryptophan has been demonstrated by absorption and fluorescence spectroscopy.
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13.
This paper comments on: Low, B. S., Alexander, R. D., and Noonan, K.M. Human hips, breast, and buttocks: Is fat deceptive? Ethology and Sociobiology 8: 249-247, 1987. In it I argue that:
  • 1.1. Sexual selection has probably not been the most important selection pressure on
  • 2.female human body shape.
  • 3.2. Male humans in different cultures find different aspects of the female body attractive
  • 4.and therefore are unlikely to have exerted consistent directional sexual selection on
  • 5.the female body.
  • 6.3. Breast size is not correlated with lactation success.
  • 7.4. Visible hip width is not correlated with parturition success.
  • 8.5. Women would lower their fitness if they tried to deceive men about their internal
  • 9.pelvic dimensions.
  • 10.6. There are many alternative hypothesis to explain the existence of fat onwomen's
  • 11.breast, hips, and buttocks.
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14.
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Highlights
  • •HLA-B*40:02 and ERAP2 are risk factors for ankylosing spondylitis.
  • •The effects of ERAP2 on the B*40:02 peptidome are defined.
  • •ERAP2 has a major influence mainly due to alterations of N-terminal residues.
  • •These effects provide a basis for the association of ERAP2 with disease.
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15.
  • 1.1. To evaluate changes in high-energy phosphate metabolism in the water scorpion (Ranatra chinensis) under restraint and cold water-warm water stresses, in vivo [31P]NMR spectra were obtained.
  • 2.2. Under restraint stress, arginine phosphate (Arg-P) decreased by 10% after 1 hr and remained at that level thereafter, while β-ATP showed negligible changes over 6 hr.
  • 3.3. As the water temperature gradually increased or decreased, the relative concentration of Arg-P decreased due to enzyme regulation.
  • 4.4. Repeated cold water-warm water stress, which consisted of repeated 15 min exposures to cold water (5°C) followed by 15 min exposures to warm water (30°C) caused distinct decreases in Arg-P and β-ATP concentration. These decreases were dependent on the frequency of exposure.
  • 5.5. Phosphomonoesters (PME) increased not only with restraint stress but also with cold water-warm water stress.
  • 6.6. The effect of cold water-warm water stress on high-energy phosphate metabolism was greater than that of restraint stress.
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16.
  • 1.1. We examined immobilization stress-induced antioxidant defense changes in rat plasma and observed the antioxidant effect of reduced glutathione (GSH) administration on these changes.
  • 2.2. Immobilization stress induced severe bleeding in the stomach and a significant increase in plasma levels of thiobarbituric acid receives substances (TBARS).
  • 3.3. Immobilization stress induced a significant decrease in plasma iron-binding, ironoxidizing protections and radical scavenging activity.
  • 4.4. Plasma levels of ascorbic acid, ascorbyl radical and superoxide dismutase activity remained unchanged following immobilization stress.
  • 5.5. Treatment with GSH showed a significant protective effect on stomach bleeding, on the increase in plasma TEARS, and on the decrease of iron-binding, iron-oxidizing protection and radical scavenging activity in plasma.
  • 6.6. These results suggest that immobilization stress induces generation of reactive oxygen species and decreases the endogenous antioxidant defenses, which can be attenuated by extracellular administration of antioxidant GSH.
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17.
  • 1.1. Cholesterol metabolism has been characterized in three species of New World primates, the cotton-top tamarin, the saddle-back tamarin, and the squirrel monkey.
  • 2.2. When fed a diet containing cholesterol, the three species exhibited differing responses of plasma cholesterol levels.
  • 3.3. Dietary cholesterol absorption was determined and plasma cholesterol die-away kinetics were analyzed in terms of a two-pool model.
  • 4.4. The results of the analyses of cholesterol turnover are consistent with the observed species-specific differences in plasma cholesterol values and cholesterol absorption.
  • 5.5. Cholesterol metabolism differs between the two tamarin species, as well as between the tamarins and the squirrel monkey.
  • 6.6. Implications of species-specific differences between tamarin species are discussed in terms of the use of tamarin species as animal models for comparative studies of cholesterol metabolism and the etiology of cancer and cardiovascular disease.
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18.
  • 1.1. Analysis of the total lipid content (TL), components of the neutral lipid fraction (NLF), phospholipid fraction (PLF), recordings of electrical potential differences and diffusional permeability were carried out in the skin of the aquatic frog Rana cyanophlyctis subjected to in vivo salt stress (0.9 sodium chloride) for different durations (0, 1, 3 and 7 days).
  • 2.2. A general decrease of skin TL and of components of the NEE and PEE was observed.
  • 3.3. Stoichiometric ratios for skin PLF components under initial salt stress of different durations reveal an increase of the ratios of sphingomyelin and phosphatidyl choline after osmotic stress.
  • 4.4. The diffusional permeability of water increased following exposure to salt stress of I, 3 and 7 days duration.
  • 5.5. The transepithelial potential difference measured in vitro after a salt stress of 3 days was considerably higher than the controls.
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19.
Breast cancer is the leading cause of cancer deaths among females, and it is estimated that each year, one in ten American women will be newly diagnosed as having the disease. It is therefore not surprising, that a great deal of effort has been made to better understand the biology of breast cancer, and that investigators keep up the search for new tools to better characterize, diagnose and treat these tumours. In this regard, the introduction of the hybridoma technique in 1975 by Kohler and Milstein has lead to an extensive work in the characterization of monoclonal and polyclonal antibodies against breast cancers. A large number of antibodies has been raised to different epitopes present in normal and neoplastic breast tissue; but unfortunately we have yet to find a highly sensitive and specific monoclonal antibody for breast cancer that can successfully be used for scintigraphic detection of nodal metastases and for radioimmunotherapy treatment of this disease.As possible radioimmunodiagnostics, antibodies are known which react with the following antigens:
  • 1.(1) cytoskeletal proteins
  • 2.(2) breast cell products
  • 3.(3) steroid receptors
  • 4.(4) putative tumor-associated antigens
  • 5.(5) oncogene products
  • 6.(6) pregnancy-related products
  • 7.(7) basement membrane antigens
  • 8.(8) degradative enzymes
  • 9.(9) cell receptors for extracellular matrix molecules
  • 10.(10) multidrug resistance gene product (p-glycoprotein)
  • 11.(11) proliferative markers.
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20.
  • 1.1. Blood flow values for the mammalian anterior uvea were not significantly different among species but was higher than that of the avian anterior uvea.
  • 2.2. Blood flow to the primate choroid was significantly higher than that of other species.
  • 3.3. The blood flow ratio which reflects the distribution of total ocular flow was significantly higher in primates than in sheep or geese.
  • 4.4. The anterior ciliary artery circulation is of major importance to anterior segment blood flow in primates but not in other mammals.
  • 5.5. Therefore primates are the only suitable models for ischemia following strabismus surgery.
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