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1.
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   

2.
  • 1.1. Accumulation and distribution of dietary Se in relation to mortality was investigated in adult house flies.
  • 2.2. The midgut preferentially accumulated Se and thereby limited toxicity.
  • 3.3. Midgut Se concentrations were from 6- to 107-fold higher than in carcass, and from 15 to 71% of the total Se was associated with midgut.
  • 4.4. When dietary levels of Se were raised the midgut saturated at 15 μg Se/g tissue, followed by a rise in carcass levels to greater than 0.5 μg Se/g tissue and increased mortality.
  • 5.5. Se levels in lysosomal fractions were from 3- to 50-fold higher than in other subcellular fractions, suggesting that Se is sequestered in lysosomes.
  • 6.6. Se added to drinking water was toxic at 4–8 ppm.
  相似文献   

3.
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
  相似文献   

4.
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   

5.
In brief     
  • Bioscrypt
  • Saflink
  • Dell
  • Fujitsu Microelectronics America
  • Identix
  • Viisage
  • Acsys Biometrics
  • US Government
  相似文献   

6.
  • 1.1. The euryaline calanoid copepod, Acartia tonsa, maintains haemolymph Na below that of the external medium in salinities above 34ooo (475 mM Na).
  • 2.2. The measured transepithelial electrical potential. −9.97 ± 1.0 mV, indicates that Na is regulated out of electrochemical equilibrium.
  • 3.3. Water osmotically lost in hyporegulation is replaced by Na-dependent absorption by the gut.
  • 4.4. High osmotic water permeability is evidenced by the fact that with an increase in external salinity from 475 mM Na to 580 mM Na the copepod's drinking rate nearly doubles.
  • 5.5. Sodium efflux measurements indicate that ionic permeability is much lower than other hyporegulating crustaceans.
  • 6.6. The energetic advantage of hyporegulation in this species is considered.
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7.
  • 1.1. Toads fed mealworms ad libitum for 24-hr periods once a week retained water in the body in amounts that varied with meal size, as well as temporally.
  • 2.2. The ratio between masses of water retained and mealworms eaten increased from about 0.5 in May to about 1.3 by mid-July, and declined again at the end of the seasonal feeding period. li[3. It is argued that this pattern reflects seasonal variation in the secretion of digestive (gastric) juice in response to meal size.
  • 3.4. The cutaneous drinking response, reflected in number of visits to the water source, increased in strength with successive feedings.
  • 4.5. It is suggested that the drinking response to feeding included a secondary, behavioural component, superimposed upon a primary response to feeding.
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8.
  • 1.1. The effects of thermal acclimatization at 10 and 24°C on heart rate were investigated on unrestrained soles (Solea vulgaris).
  • 2.2. The sensitivity of heart rate to temperature changes induced by temperature acclimatization was higher in cold-acclimatized than in warm-acclimatized soles.
  • 3.3. Heart rate of cold-acclimatized fish to temperature changes was not affected by blocking the vagal tone with atropine.
  • 4.4. After atropine treatment the ability of heart rate to show thermal compensation decreased in warm-acclimatized soles.
  • 5.5. It is suggested that the vagus nerve can function differently at different temperatures.
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9.
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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10.
  • 1.1. Among the digestive enzymes synthesized by pancreas, lipase is the principle lipolytic enzyme which hydrolyses dietary glycerides.
  • 2.2. For its action it requires a coenzyme, colipase.
  • 3.3. The molecular mechanisms of the interaction of these two are not fully understood.
  • 4.4. Further, molecular events that regulate and influence lipid absorption are ill denned.
  • 5.5. The rabbit is the conventional animal model for the study of lipid absorption. We have undertaken the molecular cloning, and characterization of rabbit pancreatic colipase, the coenzyme for pancreatic lipase.
  • 6.6. Colipase has been cloned from a gt 11 library of an adult rabbit pancreatic cDNA by probing with an oligonucleotide derived from human colipase sequence.
  • 7.7. The total reading frame consists of 321 nucleotides coding for 90 amino acids of the functional protein and 17 nucleotides of the leader peptide.
  • 8.8. Northern blot analysis revealed a distinct band around 0.5kb. Comparison with other species revealed an over all homology of 75% at the nucleotide level.
  • 9.9. At the amino acid level highest conservation is observed at the lipase-binding region (AA 53–73).
  • 10.10. Rabbit enzyme also retained the N-terminal pentapeptide of it preform.
  • 11.11. The regions of homology and conservation may aid to define the sites of interaction of colipase with lipase.
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11.
  • 1.1. Potassium loss occurs through the gills of trout.
  • 2.2. This loss is compensated by intestinal absorption.
  • 3.3. During a fasting period, branchial regulation appears after 2–3 days.
  • 4.4. The maintenance of potassium balance is discussed as a function of experimental conditions.
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12.
  • 1.1. Submandibular secretion during parasympathetic stimulation (5 Hz) was examined in streptozotocin-diabetic and age-matched control rats.
  • 2.2. At 3 weeks, but not 3 and 6 months, flow rate was initially greater than in controls, but it declined rapidly after 30 min.
  • 3.3. The reduction in flow rate was associated with oedema of the gLond.
  • 4.4. At 3 months, graded stimulation revealed a tendency to oedema at frequencies of 10 Hz and above.
  • 5.5. Morphologically, submandibular capillary density was increased in diabetic rats.
  • 6.6. Thus, in diabetes the submandibular gland appears less able to withstand continuous parasympathetic stimulation, due in part to an increase in tissue capillary area.
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13.
  • 1.1. Platelets bind specifically to lactoferrin. A significant similarity between human lactoferrin and some bovine milk proteins has been established.
  • 2.2. Because of the structural homology of lactoferrin and cows milk proteins they are able to influence lactoferrins regulatory function on the level of its binding to membrane receptors on platelets.
  • 3.3. An inhibitory effect of bovine α-lactalbumin and of β-lactoglobulin on lactoferrin-receptor interaction was shown.
  • 4.4. Bovine α-lactalbumin competes with lactoferrin for the binding sites.
  • 5.5. Scatchard plot analysis of data shows one binding site for lactoferrin in the presence of α-lactalbumin with an affinity constant, Ka = 0.46 × 109 mol/1 and 335 receptors/cell.
  • 6.6. The inhibitory effect of β-lactoglobulin reaches 62% and is different for the common fraction ⨿-lactoglobulin and the genetic variants β-lactoglobulin A and B.
  • 7.7. β-lactoglobulin does not compete with lactoferrin for the membrane receptors.
  • 8.8. Bovine casein and egg lysozyme stimulate 59Fe-lactoferrin binding to the receptors. The mechanism of these effects is still unknown.
  • 9.9. Tested alimentary antigens are able to interact with lactoferrin and also with some platelet membrane structures.
  • 10.10. Established changes in lactoferrin binding to the platelet membrane might be in relation to lactoferrins regulatory function and (or) eliminating mechanisms of these alimentary antigens.
  相似文献   

14.
  • 1.1. Procarboxypeptidase (W-PCPA) was purified from the pancreas of the sei whale Balaenoptera bolealis.
  • 2.2. W-PCPA was obtained as a homogeneous protein in polyacylamide gel disc electrophoresis.
  • 3.3. W-PCPA has a molecular weight of 75,000.
  • 4.4. Amino acid composition of W-PCPA was compared with that of bovine procarboxypeptidase as A S5 (PCPA-S5).
  • 5.5. W-PCPA may be two subunits, and the aggregate form may resemble PCPA-S5.
  相似文献   

15.
  • 1.1. The medial (MGF), lateral (LGF) and motor (RMS-2) giant neurons were confirmed as neural components in the earthworm Amynthas hawayanus polysynaptic reflex circuit by simultaneous potential recording and dye injection.
  • 2.2. The reflex was initiated from the mechanoreceptors when evoked by mechanical stimulation but electrical stimulation also evoked an antidromic response in the motoneuron.
  • 3.3. The primary reflex response propagates decrementally along both giant axons but directly evoked action potentials conduct in an all-or-none fashion.
  • 4.4. The secondary reflex response continues to propagate after the primary response disappears.
  • 5.5. A rhythmically discharging neuron of uncertain function was also identified.
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16.
  • 1.1. Electrocardiograms (ECGs) were recorded from B. bufo and R. pipiens whilst behaviourally aroused and frightened.
  • 2.2. A tachycardia was exhibited in both states, though in fright it was preceded by a “missed” beat.
  • 3.3. The difference between these responses and those of other vertebrates was discussed in relation to the amphibious habit.
  • 4.4. It is suggested that the cardiac responses of diving, fright and arousal may have a common evolutionary origin.
  相似文献   

17.
  • 1.1. There is considerable variation in the renal medullary thickness (3.4–7.7) of six mammals from islands in the Lower Florida Keys. This appears to be correlated with differences in their abilities to survive without fresh or brackish drinking water.
  • 2.2. The black rat (Rattus rattus) had the highest predicted urine osmotic pressure and the highest measured urine concentration (4300 mOsm). This species was a common inhabitant of remote mangrove islets lacking brackish water ponds and often even dry land.
  • 3.3. In captivity R. rattus maintained its body mass on a diet of rodent pellets (8% water) while drinking 26%. (75% seawater). However a process of 10 days acclimation was required. On 35%. (100% seawater), mass losses considerably surpassed gains and death occurred in seven to nine days.
  • 4.4. Thus even the most salt tolerant mammal (R. ruttus) from islands in the Florida Keys probably can not utilize seawater for drinking. It must rely on preformed and metabolic water in its food, and possibly on a temporary lens of fresh water formed during rains for water intake.
  相似文献   

18.
  • 1.1. A choriolytic enzyme was isolated from the hatching medium of the pike, Esox lucius.
  • 2.2. The enzyme is defined as hatching enzyme.
  • 3.3. The molecular weight of the enzyme is 24,000.
  • 4.4. The enzyme is a glycoprotein containing 2% carbohydrate.
  • 5.5. Its isoelectric point is 6.5.
  • 6.6. The pH optimum is around pH 8.
  • 7.7. The enzyme molecule contains two disulfide bonds but no free cysteine.
  • 8.8. Inhibitor studies and metal analysis show that the enzyme is a zinc-metalloprotease.
  相似文献   

19.
  • 1.1. Heart rate-temperature relationships were determined on unanaesthetized, unrestrained eels acclimated to 15°C and 25°C.
  • 2.2. Heart rate in eels with intact vagal tonus exhibited a nearly complete temperature compensation. The degree of compensation was considerably reduced by blocking the vagus function with benzetimide.
  • 3.3. The difference in the sensitivity of heart rate to temperature change induced by temperature acclimation was significantly decreased after benzetimide-treatment.
  • 4.4. The inhibitory vagal tonus was significantly higher in warm-acclimated than in cold-acclimated eels.
  • 5.5. It is concluded that adaptation of heart rate to temperature is mediated by the parasympathetic system to a great extent.
  相似文献   

20.
  • 1.1. The types of haemocytes during larval development were studied.
  • 2.2. The developmental profile of leucine aminopeptidase and alkaline phosphatase was studied. The maximum LAP activity was found to be in early larval development, while the maximum alkaline phosphatase during the white pupal stage.
  • 3.3. These activities were compared with those determined in cell-free haemolymph.
  • 4.4. Both hydrolytic enzymes have been found histochemically in the prohaemocytes and in the plasmatocytes.
  • 5.5. In cultured haemocytes experiments it was found that 64% of the total LAP activity was secreted into the incubation medium, while electrophoretic analysis of released LAP activity demonstrated that only LAP A isozyme was secreted.
  • 6.6. Based on the above results we suggest that both hydrolytic enzymes are functionally important throughout larval development.
  相似文献   

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