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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.
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2.
  • 1.1. The acute toxicity of endosulfan was determined for the freshwater rotifer Brachionus calyciflorus.
  • 2.2. The mean 24 hr lc50 value for endosulfan was 5.15 ppm with a coefficient of variation of 14.7%.
  • 3.3. Rotifers were exposed at two sublethal concentrations (1.5–2.0 ppm) of endosulfan for bioaccumulation experiments, for an exposure time of 24, 48, 72 and 96 hr. The rotifers were fed with Nannochloris oculata (5 × 105cell/ml).
  • 4.4. The highest accumulation of endosulfan was found 24 hr after the start of the exposure to 1.5 ppm of the toxicant. A steady-state concentration in rotifer was reached between 24–48 hr, followed by a gradual decrease until 96 hr.
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3.
  • 1.1. Guppies exposed to several triphenyltin chloride (TPTC) concentrations in water died as soon as a body burden of 20 ± 10 nmol/g fish was reached.
  • 2.2. Accumulation of TPTC during exposure in acute toxicity experiments can be predicted by using the kinetic parameters of TPTC.
  • 3.3. The lethal body burden is two orders of magnitude lower than for narcotic organic compounds such as chlorobenzenes.
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4.
  • 1.1. The oxygen consumption of crabs in normoxic and hypoxic (50% O2) seawater was measured directly after collection.
  • 2.2. The influences of size and lunar cycles were removed by scaling the data.
  • 3.3. Strong negative correlations between low individual levels of O2 consumption and the ability to compensate for hypoxia were apparent in Wicklow (subtidal) crabs.
  • 4.4. Compensation for hypoxia was much greater on the flood tide than on the ebb.
  • 5.5. Crabs from Roscoff (intertidal) had lower levels of compensation than those from Wicklow.
  • 6.6. Size, sex and condition had no apparent effect upon these relationships.
  • 7.7. Crabs acclimated to laboratory conditions have not shown this tidal variation in compensation for hypoxia.
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5.
  • 1.1. Main serum α1-protein (α1P) of rainbow trout was purified and its biochemical and physico-pathological properties were studied.
  • 2.2. α1P was suggested to be a primitive protein having both properties of albumin and AFP in serum proteins of mammals according to the following results.
  • 3.3. Molecular weight (75,000), two kinds of molecules (pI 4.55 and 5.05) and amino acid composition.
  • 4.4. Dye- or ConA binding activity.
  • 5.5. Estrogen binding activity and inhibitory effect on lymphoblastoid-forming activity.
  • 6.6. Possible osmotic regulator.
  • 7.7. Significant elevation of blood α1P level in the course of hepatoma induction.
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6.
  • 1.1. The effects of several phenols, anilines and aliphatic alcohols on yeast plasma membrane H+-ATPase and purine transport system as well as on Na+, K+-ATPase and adenosine uptake by Chinese hamster ovary cells (CHO) were investigated.
  • 2.2. In all cases an inhibition was observed, which could be correlated with the octanol/water partition coefficients of the substances tested, thus making quantitative structure-activity predictions possible.
  • 3.3. The observed effects correlated well with the influence of the chemicals on cell growth.
  • 4.4. The results suggest a common mechanism of toxicity by the action of hydrophobic xenobiotics on biomembranes.
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7.
  • 1.1. The properties of ATPase activity were studied with the cells at the early stationary phase of Saccharomycopsis fibuligera.
  • 2.2. Optimal pH for the activity was approximately 7.
  • 3.3. The activity was stimulated by Mg2+.
  • 4.4. The activity was inhibited by NaF, DCCD, oligomycin, NaN3, NaVO3, or PCMB but not inhibited by ouabain.
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8.
  • 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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9.
  • 1.1. Pseudomonas aeruginosa phospholipase C from culture supernatants of bacteria grown in high-Pi basal salt medium with choline, as the sole carbon and nitrogen source, was purified by precipitation with 70% saturation ammonium sulfate in the presence of celite.
  • 2.2. The PLC activity was eluted of this mixture by the use of a reverse gradient of 70-0% ammonium sulfate.
  • 3.3. The peak containing the PLC activity revealed a single protein after SDS-PAGE.
  • 4.4. The method could also be applied to purify PLC produced in a low-Pi complex medium. The resultant preparation was not homogeneous.
  • 5.5. The molecular weight for both PLC preparations was about 70 kDa.
  • 6.6. Both PLC used phosphatydilcholine and sphingomyelin as substrates, displayed hemolytic activity an exhibited an apparent KM of 25 mM for p-nitrophenylphosphorylcholine.
  • 7.7. They were not inhibited by 1% sodium deoxycholate but were 30% inhibited by 1% Triton X-100.
  • 8.8. 2% sodium dodecylsulfate and 1% tetradecyltrimethylammonium bromide inhibited the PLC from the HPl-BSM plus choline but not the enzyme from the LPl-CM.
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10.
  • 1.1. Blood parameters determining oxygen capacity and oxygen affinity were measured in brown trout at different times of the year.
  • 2.2. Haematological data indicate a slight decrease in blood oxygen capacity during the warm seasons. 3. Oxygen affinity increases significantly during summer and decreases in winter.
  • 3.4. The changes in P50 exhibited a positive correlation with the amount of anodic haemoglobin components, and a negative correlation with the amount of cathodic haemoglobin components.
  • 4.5. The changes observed in the [ATP]/[Hb] molar ratio were not correlated with oxygen affinity and gave values near one.
  • 5.6. We conclude that the oxygen affinity increase could be a physiological adaptation to oxygen transport during the wanner period. A possible mechanism is discussed.
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11.
  • 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.
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12.
  • 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.
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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 effect of incorporating D2O into the incubation medium on glycolysis and gluconeogenesis by hepatocytes from fasted rats was examined.
  • 2.2. The substitution by heavy water, D2O, at concentrations from 10 to 40%, stimulated glucose uptake, lactate production and CO2 yields from glucose. At 10 mM glucose, 40% D2O doubled glucose uptake, increased CO2 production by 40%, and increased lactate production by 350%.
  • 3.3. The stimulation of lactate production decreased at higher glucose concentrations, but was still substantial even at 80 mM glucose.
  • 4.4. There was no effect on CO2 production above glucose concentrations of 30 mM.
  • 5.5. Ten percent D2O showed little inhibition of lactate uptake, its oxidation and gluconeogenesis. At 40% D2O the inhibition ranged from 10 to 20%.
  • 6.6. No effect of D2O on the rate of glucokinase or glucose-6-phosphatase was observed.
  • 7.7. The concentration of fructose, 2,6-P was not affected by D2O
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15.
  • 1.1. The toxicity of the fungicide benomyl to terrestrial enchytraeid species was tested under different conditions.
  • 2.2. Despite a relatively low acute response even to higher concentrations in agar media, sensitive effects were observed for cocoon production and hatching success at the recommended concentration for agricultural application (5.9 ppm in the test medium).
  • 3.3. These sublethal effects could be reconciled with population tests in larger quantities of soil: lower abundance was due to a very low number of juveniles in the benomyl-treated cultures.
  相似文献   

16.
  • 1.1. Phospholipase A2 was isolated from Agkistrodon bilineatus venom by Sephadex G-75 and CM-Cellulose column chromatographies.
  • 2.2. The purified phospholipase A2-I gave a single band on disc polyacrylamide gel electrophoresis, isoelectric focusing and sodium dodecyl sulfate polyacrylamide gel electrophoresis.
  • 3.3. The enzyme preparation had a molecular weight of 14,000, isoelectric point of pH 8.77 and possessed 123 amino acid residues.
  • 4.4. The purified phospholipase A2 possessed lethal, indirect hemolytic and anticoagulant activities.
  • 5.5. The enzyme hydrolyzed the phospholipids phosphatidyl choline (PC), phosphatidyl ethanolamine (PE), phosphatidyl inositol (PI) and phosphatidyl serine (PS).
  • 6.6. The concentration of mouse diaphragm was inhibited and the contraction of guinea pig left atrium was increased by phospholipase A2-I.
  • 7.7. Phospholipase A2 activity of this preparation was inhibited by ethylenediamine tetraacetic acid, p-bromo phenacyl bromide, n-bromo succinimide or dithiothreitol, but not by diisopropyl fluorophosphate or benzamidine.
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17.
  • 1.1. The regulation of ions at similar concentrations in most individuals of a species suggests the existence of internal reference standards.
  • 2.2. Few have been identified, but many probably relate to cell membrane properties, including potentials, surface charge densities and equilibrium constants of receptor molecules.
  • 3.3. Solubility may sometimes determine the product [Ca2+][CO32−].
  • 4.4. Reference standards must generally each relate to more than one ionic species.
  • 5.5. For some concentrations, including osmolality, there may be no direct reference standard.
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18.
  • 1.1. The carnitine-responsive mutant yeast, Candida pintolopesii ATCC 26014 and the wild type strain (ATCC 22987) were used to investigate the role of carnitine and the carnitine acetyltransferase system.
  • 2.2. [3H]l-Carnitine, supplied to the cells, was incorporated into acetylcamitine and [14C]pantothenate was incorporated into CoA and its derivatives.
  • 3.3. Both bioautography and quantitative assays indicated that the relative amounts of CoA and acetylCoA were very different in the mutant and wild type cells.
  • 4.4. The wild type yeast maintained an acetylCoA/CoA ratio of 0.33 ± 0.09 indicating that most of the CoA in the cell is in the free CoA form. Carnitine was not required to establish this ratio nor did its presence lower it further.
  • 5.5. In contrast, the mutant cells contained a high acetylCoA/CoA ratio (12.8 ± 3.0).
  • 6.6. In the mutant cells, carnitine lowered the ratio by decreasing the intracellular acetylCoA concentration and releasing free CoA.
  • 7.7. These data indicated that wild type yeast possess an effective mechanism that is not related to the CAT system for regulating the acetylCoA/CoA ratio.
  • 8.8. This mechanism appears to be lacking in the mutant. The CAT system decreased the acetylCoA/CoA ratio in the mutant cells but not to the value which is found in the wild type strain.
  • 9.9. In both stains of Candida pintolopesii, in the presence of carnitine, an acetylcamitine pool can be created whose concentration exceeds that of acetylCoA.
  • 10.10. The intracellular apparent equilibrium constant (Kapp) for carnitine acetyltransferase for wild type Candida pintolopesii ATCC 22987 was 0.73 ± 0.12, close to the established value of 0.6, indicating that the CAT system ran close to equilibrium.
  • 11.11. The Kapp for the CAT system of the carnitine-responsive mutant yeast was 7.7 ± 1.7 indicating that this reaction was not at equilibrium.
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19.
  • 1.1. Subcellular distribution of (NA+, K+-ATPase and ouabain-insensitive ATPase (Mg2+-ATPase) are compared in branchial tissues of the euryhaline crab, Eriocheir sinensis, acclimated to fresh water.
  • 2.2. Both the anterior and posterior gills contain cAMP-dependent protein kinase and endogenous protein substrate for phosphorylation.
  • 3.3. Phosphorylation occurs in both “particulate” and “soluble” subcellular fractions but its stimulation by cAMP is restricted to the “soluble” fraction.
  • 4.4. serotonin (5-HT) and dopamine receptors are present only in the “light particulate” fraction isolated from the posterior gills.
  • 1.(a) Serotonin and dopamine have no effect on the phosphorylation observed in a subcellular fraction alone.
  • 2.(b) Activation of the phosphorylation by serotonin and dopamine is found when the soluble fraction (source of cAMP-dependent protein kinase) is added to the fraction P3 from the posterior gills.
  • 3.(c) No activation occurs with the fractions P3 as well as P1 or P2 (not shown) from anterior gills of fresh water crab.
  • 4.(d) Cyproheptadine, a serotonin receptor antagonist, inhibits the 5-HT dependent increase in phosphorylation.
  • 5.(e) The dopamine receptor antagonist, chlorpromazine, inhibits dopamine-stimulated phosphorylation.
  • 6.5. Ouabain mimics the effect of cyproheptadine on the serotonin-stimulated phosphorylation found in the posterior gills.
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20.
  • 1.1. To understand the physiological roles of the 90-kDa stress protein (HSP90), we investigated the heparin- and antibody-binding domains of the protein.
  • 2.2. For heparin-binding sites, HSP90 was digested completely with trypsin, and the digests were applied to a heparin-Sepharose column and eluted with 1.0 M NaCl, followed by 8.0 M urea.
  • 3.3. Each elutant was purified by a reverse-phase C18 column.
  • 4.4. Two peptides from the NaCl-eluted fraction and no peptide from the urea-eluted fraction were purified.
  • 5.5. The purified peptides were sequenced by an automated peptide sequencer.
  • 6.6. One of the heparin-binding sites was present between Leu-362 and Arg-365; another was present between Leu-645 and Lys-648.
  • 7.7. These two peptides were basic and considerably hydrophilic.
  • 8.8. For antibody-binding sites, HSP90 was mildly digested with trypsin, electrophoresed on SDS-polyacrylamide gels and transferred to PVDF membranes.
  • 9.9. The four bound of the trypsin fragments could be sequenced with a peptide sequencer.
  • 10.10. There was only one antibody-binding peptide, 38 kDa, starting from Pro-2. The others showed no cross-reactivity with the antibody and started from Leu-283.
  • 11.11. Therefore, the epitopes of HSP90 are present between Pro-2 and Leu-282.
  • 12.12. The heparin-binding sites are present from the middle region of the HSP90 molecule, and the antigen sites are at the N-terminal domain.
  相似文献   

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