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1.
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.
  相似文献   

2.
  • 1.1. Fundamental chitin digestion characteristics of Crassostrea virginica crystalline style were investigated.
  • 2.2. Optimum temperature and pH were 34°C and 4.8. respectively.
  • 3.3. The colloidal regenerated chitin (0.56mol/0.5 ml: GlcNAc equivalents) was saturating under all enzyme levels encountered.
  • 4.4. There was no evidence of end product inhibition, even after 100 hr incubation.
  • 5.5. Calculated Km for the chitinase complex was 1.19mM when determined using a 30 min assay, but was only 0.70 mM when determined using a 4.6 hr assay.
  • 6.6. Both Km values are lower than reported for similar assays in other molluscs and for most bacteria.
  • 7.7. Effect of substrate preparation on the kinetics are discussed.
  • 8.8. Eight peaks of chitinase activity were resolved by DEAE-Fractogel ion exchange chromatography.
  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.
  • 1.1. An alkaline p-nitrophenylphosphate phosphatase has been purified 440-fold from extracts of Hatobacterium halobium.
  • 2.2. The enzyme has an apparent molecular weight of 24,000.
  • 3.3. A Km value for p-nitrophenylphosphate of 1.12mM has been found under optimal conditions.
  • 4.4. The enzyme is selectively activated and stabilized by Mn2+.
  • 5.5. It requires high salt concentrations for stability and maximum activity.
  • 6.6. It displays an unusual restricted substrate specificity of 25 phosphate esters tested, only phosphotyrosine and casein were hydrolysed besides p-nitrophenylphosphate.
  相似文献   

5.
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.
  • 1.1. A purification procedure for a thioredoxin from the extremophilic archaeon Sulfolobus solfataricus is described.
  • 2.2. The thioredoxin is active in the dithiothreitol-dependent reduction of insulin disulfide bonds.
  • 3.3. The thioredoxin is a monomer of 24,800 Da; it is an acidic protein with a pi of 4.5.
  • 4.4. The protein is stable to heating for 3 hr at 90°C.
  • 5.5. The amino acid composition of S. solfataricus thioredoxin is reported.
  相似文献   

8.
  • 1.1. The specific activity of GMP synthetase was measured in several human tissues and found to be highest in cultured skin fibroblasts, followed by bone marrow, leukocytes, erythrocytes. placenta, and liver.
  • 2.2. The enzyme from fibroblasts was purified approximately 50-fold by ammonium sulfate fractionation and gel filtration.
  • 3.3. The Km values were determined to be 4.9μM for XMP, 270μM for ATP. and 340 μM for glutamine.
  • 4.4. Ammonium sulfate could replace glutamine as the amino donor but was much less efficient.
  • 5.5. The enzyme was specific for ATP as the energy source.
  • 6.6. Unlike the calf thymus enzyme, the human enzyme has no requirement for a reduced sulfhydryl compound.
  • 7.7. Human GMP synthetase is inhibited by ATP, dATP, azaserine, and hydroxylamine.
  相似文献   

9.
  • 1.1. Seven natural populations of Dacus dorsalis were analyzed for a dimeric esterase by means of horizontal starch-gel electrophoresis.
  • 2.2. The electrophoretic phenotypes were governed by nine codominant Est-D alleles.
  • 3.3. The commonest allele in all seven population samples was Est-D100 which encoded an electrophoretic band with intermediate mobility.
  • 4.4. The distribution of EST-D phenotypes were in accordance with Hardy-Weinberg expectations.
  • 5.5. There was no geographic variation in the distribution of Est-D alleles.
  相似文献   

10.
  • 1.1. The locust vitellogenin (VTG) receptor which is embedded in oocyte plasma membranes is a glycoprotein.
  • 2.2. With various lectins oligosaccharide units have been identified, among them neuraminic acid linked to Gal or GalNAc, mannose chains, Gal linked to GalNAc or GlcNAc and fucose linked to GlcNAc.
  • 3.3. With specific enzymes it could be shown that mannose and most other oligosaccharides are O-linked while others like fucose are N-linked.
  • 4.4. Enzymatic removal of all O-linked carbohydrates resulted in a drop of the molecular mass of the receptor protein from 200,000 to 110,000.
  • 5.5. A total of N- and O-linked oligosaccharides of 54% was calculated.
  • 6.6. The isoelectric point of the receptor was found to be at pH 3.4 increasing slightly after removal of neuraminic acid.
  • 7.7. Removal of neuraminic acids destroyed the binding ability for VTG.
  相似文献   

11.
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   

12.
  • 1.1. Carp red cells were treated with drugs that affect the cell membranes. The water content of the cells and the accumulation of cAMP in the cells were measured in normoxia and in hypoxia using non-stimulated and adrenergically stimulated cells.
  • 2.2. WGA, DIDS + CCCP and A23187 increased the water content of nonstimulated normoxic cells.
  • 3.3. In hypoxia ouabain and DIDS + CCCP increased the water content but cytochalasin B, NPM, DIDS, CCCP and A23187 + CA2+ abolished the hypoxia-induced swelling.
  • 4.4. Any membrane perturbation induced some cAMP formation, Sophora and Anquilla lectins being most potent.
  • 5.5. Also in adrenergically stimulated cells, membrane perturbation generally increased cAMP formation.
  • 6.6. However, cAMP accumulation diminished in cells treated with cytochalasin B, CCCP and DIDS + CCCP.
  • 7.7. The adrenergic swelling of carp red cells was reduced in normoxia by DIDS. NPM and CCCP increased the adrenergic swelling in normoxia to hypoxic level.
  • 8.8. In hypoxia WGA and Anquilla lectin decreased the swelling.
  相似文献   

13.
  • 1.1. A new tetralysine endopeptidase from Escherichia coli AJ005 has been purified about 135-fold.
  • 2.2. The peptidase seems to be specific to tetralysine among lysine homopolymers.
  • 3.3. The optimal pH was about 7.5
  • 4.4. The activity was inhibited by KCN but not inhibited by soybean trypsin inhibitor.
  • 5.5. The apparent Km value was 2.5 × 1O−3 M for tetralysine.
  相似文献   

14.
  • 1.1. The hydrolysis of glycol chitin preparations by several β-N-acetylglucosaminidases was monitored colorimetrically with the potassium ferriferrocyanide reagent.
  • 2.2. Glycol chitin samples from crab and insect sources varied considerably in chemical composition and susceptibility to enzymatic hydrolysis.
  • 3.3. Insect endochitinase preferred crab glycol chitin as substrate while hen's egg white lysozyme preferred commercial glycol chitin.
  • 4.4. Insect glycol chitin was well hydrolyzed by both enzymes.
  • 5.5. Insect exochitinase did not digest glycol chitin.
  相似文献   

15.
  • 1.1. To characterize an enzyme which metabolizes retinal in liver microsomes, several properties of the enzymatic reaction from retinal to retinoic acid were investigated using rabbit liver microsomes.
  • 2.2. The maximum pH of the reaction in the liver microsomes was 7.6.
  • 3.3. The Km and Vmax values for all-trans, 9-cis and 13-cis-retinals were determined.
  • 4.4. The reaction proceeded in the presence of NADPH and molecular oxygen.
  • 5.5. The incorporation of one atom of molecular oxygen into retinal was confirmed by using oxygen-18, showing that the reaction comprised monooxygenation, not dehydrogenation.
  • 6.6. The monooxygenase activity was inhibited by carbon monoxide, phenylisocyanide and antiNADPH-cytochrome P-450 reductase IgG, but not by anti-cytochrome b5 IgG.
  • 7.7. The enzymatic activity inhibited by carbon monoxide was photoreversibly restored by light of a wavelength of around 450 nm.
  • 8.8. The retinal-induced spectra of liver microsomes with three isomeric retinals were type I spectra.
  • 9.9. The microsomal monooxygenase activity induced by phenobarbital or ethanol were more effective than that by 3-methylcholanthrene, clotrimazole or β-naphthoflavone.
  • 10.10. These results showed that the monooxygenase reaction from retinal to retinoic acid in liver microsomes is catalyzed by a cytochrome P-450-linked monooxygenase system.
  相似文献   

16.
In brief     
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  • Saflink
  • Dell
  • Fujitsu Microelectronics America
  • Identix
  • Viisage
  • Acsys Biometrics
  • US Government
  相似文献   

17.
  • 1.1. An elastase-like enzyme was purified from the pyloric caeca of rainbow trout by hydrophobic interaction, cation exchange and gel-filtration chromatography.
  • 2.2. The approximate molecular weight of the elastase was 27 kDa and the isoelectric point was remarkably basic.
  • 3.3. The pH optimum of this enzyme was 8.0, when assayed with Succinyl-Ala-Ala-Ala-p-Nitroanilide.
  • 4.4. When assayed with Succinyl-Ala-Ala-Ala-p-Nitroanilide, the enzyme activity had a temperature optimum of 45°C, and the enzyme was stable up to this temperature.
  • 5.5. The trout elastase exhibited a higher specific activity than porcine elastase against Succinyl-Ala-Ala-Ala-p-Nitroanilide and elastin-orcein.
  • 6.6. The trout elastase was inhibited by elastatinal, PMSF, TPCK, SBTI and Bowman-Birk inhibitor.
  相似文献   

18.
  • 1.1. A lipoxygenase activity was purified from Thermoactinomyces vulgaris and some of its properties were characterized.
  • 2.2. The enzyme showed a temperature activity range of 40–55°C with still significant activity over 60°C.
  • 3.3. The pH of activity on linoleic acid had a broad range with an optimum at pH 6.0 and a weaker one at pH 11.0.
  • 4.4. On arachidonic acid the pattern was narrow bell-shaped with an optimum at pH 6.5.
  • 5.5. The purified lipoxygenase from Th. vulgaris showed an apparent Km of 1 mM and Vmax of 0.84 μmol diene/min/mg protein.
  • 6.6. It was inhibited by the oxidation products, 9-HPOD and 13-HPOD.
  • 7.7. A 160,000 Da molecular weight of the enzyme was determined by molecular filtration. Methionine, tyrosine, tryptophan and cysteine are apparently involved in its activity.
  相似文献   

19.
  • 1.1. A lipoxygenase preparation was obtained from Thermoactinomyces vulgaris and was purified by affinity chromatography on a linoleyl aminoethyl sepharose column.
  • 2.2. Two active fractions were obtained.
  • 3.3. The fraction obtained by elution with 100 mM borate buffer pH 9.0 was used in the subsequent work.
  • 4.4. Th. vulgaris lipoxygenase oxidized linoleic acid into two products: 13-HPOD and 9-HPOD at a ratio of 44 to 56, respectively.
  • 5.5. The identification and characterization of the isomers was done by HPLC, I.R. and mass spectrometry.
  • 6.6. When arachidonic acid was used as substrate, 15-HPETE and 15-HETE were found to be the main enzymatic products.
  相似文献   

20.
  • 1.1. Six different monoclonal IgG mouse antibodies to heparin lyase I from Flavobacterium heparinum were prepared.
  • 2.2. The monoclonal antibodies were used to detect heparin lyases I, II and III by dot-blotting immunoassay and by Western blotting.
  • 3.3. Individual antibodies showed different reactivity toward the three heparin lyases.
  • 4.4. The reactivity of two of the monoclonal antibodies was destroyed by exposing heparin lyases to sodium dodecyl sulfate.
  • 5.5. The antibodies can be used to rapidly distinguish between the three heparin lyases.
  相似文献   

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