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1.
  • 1.1. Growing male kittens were fed an 18% casein diet supplemented with 2, 3, or 4% l-methionine (MET) for 6 weeks.
  • 2.2. Free MET concentration in liver increased 30-fold and cystathionine two- to three-fold; the activity of adenosyl-MET transferase and cystathionase also increased but remained lower than previously found in rats.
  • 3.3. Taurine concentration in liver decreased in cats fed excess MET and appeared to depend on taurine intake.
  • 4.4. Alanine aminotransferase activity was high in all groups while serine dehydratase activity was very low.
  • 5.5. Pyruvate kinase and malic enzyme activities which are normally low in cat liver increased after excess MET. Also, glucose 6-phosphate and 6-phosphogluconate dehydrogenases increased.
  • 6.6. Cat liver metabolism showed limited adaptation to an excess dietary intake of methionine compared to that found in rats.
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2.
  • 1.1. Bending tests were performed on intact arms of two starfishes of different orders to obtain stiffness of the arm.
  • 2.2. Linckia laevigata without stimulation showed a wide variety of arm stiffness of 2.24–51.3 MPa (average: 8.0 MPa). Mechanical stimulation increased the stiffness by 2.5 times.
  • 3.3. In Asterias forbesii, isolated arms were 23 times stiffer than intact ones. Anesthesia with 0.1% MS-222 or menthol-saturated sea water increased the stiffness by 7–170 times.
  • 4.4. Ion dependence of stiffness suggests that the catch connective tissue was involved in the stiffness change.
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3.
  • 1.1. Cat liver microsomes contain the multifunctional enzyme glucose-6-phosphatase.
  • 2.2. High specificity was shown for the phosphohydrolase as well as for the transferase activity.
  • 3.3. Both activities have high Vmax values determined in optimized conditions.
  • 4.4. The phosphate transfer with carbamyl-phosphate as a phosphoryl donor and d-glucose as acceptor is consistent with a random mechanism in which the binding of one substrate decreases the enzyme's affinity for the second substrate.
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4.
  • 1.1. Carnitine concentrations were determined in placentae of mouse, marmoset and man. Mouse placenta contained about 10 times more carnitine (>2,000 nmols/g fresh tissue) than the other placentae.
  • 2.2. Carnitine acetyltransferase (CarAc) activity was abundant in all placentae.
  • 3.3. Solubility characteristics of human placental CarAc were examined.
  • 4.4. Some kinetic characteristics of partially purified human placental CarAc were obtained.
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5.
  • 1.1. The metabolism of Cu, Zn, Cd and Hg in lower vertebrates is described, using fish as a model.
  • 2.2. The main part of this review deals with metallothionein and the role of this protein for the storage and detoxification of these metals.
  • 3.3. Factors influencing the bioavailability and probable uptake routes are identified.
  • 4.4. The distribution of the metals within the organism is outlined. The distribution between tissues is described and the subcellular distribution discussed with reference to metallothionein.
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6.
  • 1.1. Phosphatase activities were determined in various seminal fluid and plant tissues.
  • 2.2. Human semen showed a markedly higher phosphatase activity, and some plants and mushrooms exhibited a considerably higher phosphatase activity.
  • 3.3. Phosphatase purified from human seminal fluid showed a pH optimum of 5–6 and was potently inhibited by l-(+)-tartrate.
  • 4.4. Tartrate could not inhibit most plant phosphatases, but inhibited the mushroom phosphatase with a one-order lower affinity than that of the seminal enzyme.
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7.
  • 1.1. Cytosolic and microsomal epoxide hydrolyzing enzymes of human skin and liver were compared and found to be different.
  • 2.2. Epidermal and hepatic cytosolic epoxide hydrolases were different in terms of substrate selectivity, pI, inhibitor sensitivity and affinity Chromatographic properties.
  • 3.3. Microsomal epoxide hydrolases had the same pIs but different substrate selectivities.
  • 4.4. Cytosolic epoxide hydrolase from adults had higher specific activity than that from neonates or cultured epidermis, but lower activity than adult hepatic enzymes.
  • 5.5. The sizes of cytosolic epoxide hydrolase from epidermis and liver were similar and lower than that from cultured fibroblasts.
  • 6.6. Cytosolic epoxide hydrolase from all sources shared similar antigenic determinants.
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8.
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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9.
  • 1.1. The effect of regular handling on fear reactions was investigated in mallard (Anas platyrhynchos) by exposing six hand-reared and four wild ducks to an approaching human being and recording heart rates with an external ECG device.
  • 2.2. All ducks reacted to the approach with tachycardia, but the response was significantly less in tame birds.
  • 3.3. Hand-reared females showed less response than males. No sex-linked differences were apparent in the wild ducks.
  • 4.4. Decreasing responses throughout the experiments were only found in tame birds.
  • 5.5. Fear or stress reactions can apparently be diminished through habituation induced by regular handling.
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10.
A brief survey of a few ideas related to marine helminths from a taxonomist's point of view shows that, while we know rather a small amount about the topics mentioned, there are likely to be numerous areas where further work will turn up interesting results. It is worth summarising here some of the areas where marine helminthologists can materially increase our understanding of the evolution of helminths in the sea. These include:
  • 1.1) Study of the development of associations and parasitism in mainly free-living groups (e.g. turbellarians);
  • 2.2) Study of “intermediate” or unusual forms by much further and wider collecting (e.g. the Southern Hemisphere fauna is poorly known);
  • 3.3) Study by modern phylogenetic techniques of various marine helminth groups at all levels, including careful and critical taxonomic revisions;
  • 4.4) Application of biochemical and karyological techniques to closely related marine forms whose status is not yet clear;
  • 5.5) Careful study of sympatric congeneric species pairs;
  • 6.6) Introduction of developmental ideas into evolutionary studies;
  • 7.7) Application of new phylogenetic insights relating to host-groups in further tests of Farenholz' Rule.
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11.
  • 1.1. The recorcling sites of 68 acoustical (A), 86 visual (V) sensitive units and 36 bimodal units, predominantly encountered within the torus semicircularis, have been examined with respect to their response characteristics.
  • 2.2. Bimodal units are located more rostrally than A units, but no topographic preference has been found for the V units. The response signs of the three modality types (excitatory, inhibitory for the A modality; On, Off for the V modality) also show no topographic organization.
  • 3.3. The spontaneous spike rate of the V type is smaller than that of the A and bimodal type. Many bimodal cells showed spontaneous activity (76%). Non-spontaneous units are more numerous in the rostral torus.
  • 4.4. The frequency sensitivity of the A units can be divided into H (high frequency) and B (broadband) units.
  • 5.5. B units, which frequently show a more complex excitatory-inhibitory behaviour are located in the middle and caudal part, whereas the H units are mainly found in the rostral part of the torus.
  • 6.6. Phase-locking is restricted to spontaneous, monomodal B units.
  • 7.7. Clusters of neurons can be found in the torus, which contain either A or V units. In the dorso-ventral direction the A clusters are about half the size of the V clusters.
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12.
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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13.
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   

14.
  • 1.1. In most cases, when isolated adipocytes and adipose tissue slices from the same animal were stimulated with various lipolytic agents (adrenergie agonists, theophylline, adenosine deaminase), the qualitative response was similar.
  • 2.2. There were, however, numerous exceptions; e.g. quinterenol did not affect isolated adipocytes whereas it was a partial agonist for adipose slices from the same animal.
  • 3.3. The adipocytes present in slices were larger than those isolated from slices by collagenase digestion.
  • 4.4. Isolated adipocytes were not more sensitive than tissue slices to stimulation by lipolytic agents.
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15.
  • 1.1. The crystallin proteins of numerous species belonging to different classes of vertebrates have been studied.
  • 2.2. Species-specific crystallin patterns are revealed which unequivocally characterize the different species.
  • 3.3. A marked variability in the number and percentage of alpha-, beta- and gamma-crystallins were found in the various species.
  • 4.4. The gamma-crystallin family, with a meagre number of common bands, has proved to be most representative of the species. The beta-crystallins, with their greater number of common bands, have been best preserved throughout vertebrate evolution.
  • 5.5. From the similarity coefficient matrix a dendrogram is drawn up, a visual phylogenetic summary of the interrelationships between the vertebrates considered.
  • 6.6. In the Discussion, other aspects are considered, such as lens morphology, functionality, animal age, post-synthetic modifications and genetic factors.
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16.
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   

17.
  • 1.1. It was confirmed that, under anaerobic conditions, fowl spermatozoa formed lactate from glucose thirteen times faster than turkey spermatozoa.
  • 2.2. The profiles of glycolytic enzyme activities were similar for spermatozoa from both species; however fowl spermatozoal activities were generally 2- to 4-fold higher.
  • 3.3. Exceptions were glycerophosphate mutase and lactate dehydrogenase activities which were respectively 9.5 and 41 times greater in fowl spermatozoa.
  • 4.4. In both species, spermatozoal glyceraldehyde-3-phosphate dehydrogenase had the lowest activity of the glycolytic enzymes.
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18.
  • 1.1. Albumin purified from rhesus monkey (MSA) shows immunological cross-reactivity with human serum albumin (HSA) by RIA.
  • 2.2. The amino-terminal sequence of MSA shows a high degree of homology to HSA.
  • 3.3. Thirty minutes after injection of radioactive leucine directly into the portal vein, albumin was purified chemically from the liver, kidneys and serum.
  • 4.4. At this time, 15% of the label was incorporated into liver homogenate protein.
  • 5.5. A highly labelled immunoreactive albumin form was purified from liver to constant specific radioactivity and separated from tissue and serum albumin.
  • 6.6. The specific radioactivity of this proalbumin was 36-times higher than the specific radioactivity of albumin in liver tissue.
  • 7.7. These similarities to HSA suggest that this non human primate species can serve as a useful model of human albumin synthesis in vivo.
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19.
In brief     
  • Bioscrypt
  • Saflink
  • Dell
  • Fujitsu Microelectronics America
  • Identix
  • Viisage
  • Acsys Biometrics
  • US Government
  相似文献   

20.
  • 1.1. The toxic effects of adenosine and deoxyadenosine on lymphocytes from horses were evaluated.
  • 2.2. Mitogen-stimulated peripheral blood lymphocytes (PBL) were found to be more sensitive to the inhibitory effects of adenosine than were lymphocytes from spleen, lymph node and thymus.
  • 3.3. Adenosine deaminase activity was approximately 10 times lower in horse lymphoid tissue in comparison to that found in human lymphoid tissue. In horse, the highest activity was in spleen while the lowest activity was in thymus.
  • 4.4. Adenosine inhibition of mitogenesis in PBL was prevented by uridine or cytidine, suggesting pyrimidine starvation as the major mechanism for adenosine toxicity.
  • 5.5. Deoxyadenosine inhibition of mitogenesis in PBL was not prevented by the addition of various ribo- or deoxyribonucleosides. This and the finding that treated cells show no increase in deoxyATP suggest that some other mechanism for deoxyadenosine toxicity other than deoxyATP inhibition of ribonucleotide reductase operates in horse PBL.
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