首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
  • 1.1. Analysis of the Soret spectra of hemoglobins A, S and F has been used to determine the extent of heme exposure and release from these hemoglobins in the presence of several solvent perturbants.
  • 2.2. Oxyhemoglobin S unfolding in the presence of either urea or propyl urea resulted in greater heme exposure and release than either oxyhemoglobins A or F.
  • 3.3. Methemoglobin formation resulted in lower denaturation midpoints for each hemoglobin compared to the reduced oxyhemoglobin state; methemoglobin F had the lowest denaturation midpoint under isothermal denaturing conditions.
  • 4.4. Rate of heme exposure was greater for oxyhemoglobin S than oxyhemoglobin A in the presence of 200 μM the anionic detergent sodium dodecyl sulfate.
  • 5.5. Evidence for increased levels of heme release in hemoglobin S may be related to the greater tendency of sickled red cell membranes to undergo lipid oxidation.
  相似文献   

2.
  • 1.1. The P50 values of extracellular hemoglobin (Hb) of five Artemia populations from different geographical origin are affected by temperature.
  • 2.2. The free oxygen binding energy is high for all the populations (ΔH between −34.7 and −56.2kj/mol).
  • 3.3. A possible correlation between thermal sensitivity of Hb and the ambient temperature of the habitat must be considered very carefully.
  • 4.4. The occurence of different quantities of Hb1 (αα chains) Hb2 (αβ chains) and Hb3 (ββ chains) in the different populations possibly influences thermal sensitivity.
  相似文献   

3.
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   

4.
  • 1.1. A starvation test was conducted in small beakers with stage 1 (S1) and stage 2 (S2) Macrobrachium rosenbergii larvae to determine optimal salinities.
  • 2.2. Experiments were first performed with S2 larvae at 13 ppt to identify a suitable medium made with artificial sea salts.
  • 3.3. A broad-range (0–35 ppt) and a subsequent narrow-range (9–16 ppt) salinity experiment with S2 larvae were used to identify 13 ppt as the optimal salinity, with 12 ppt as the next best; this agrees well with most previous estimates of optimal salinities for rearing larvae.
  • 4.4. S1 larvae were also tested in a narrow-range salinity experiment but were not used further because, unlike starved S2 larvae, they molted during the experiment.
  • 5.5. Identification of the optimal salinity was not affected by 50% daily water exchange or by bright light.
  • 6.6. Exposure of larvae to three different salinities—7, 13 and 19 ppt—during S1 influenced the width of the optimal salinity range for S2 larvae.
  相似文献   

5.
  • 1.1. Oxygen equilibrium curves were measured on trout red blood cell suspensions at pH 7.8 and 8.4 at 15, 20 and 25 C. Normal red cells and red cells that had been depleted of their ATP content were used.
  • 2.2. The equilibrium data were fitted to the Adair's model and the enthalpy (ΔH) and entropy (ΔS) changes for the first and fourth steps of oxygenation and for overall oxygenation were calculated from the temperature dependencies of the Adair constants.
  • 3.3. For normal red blood cells, the apparent heat for the first oxygenation step, δh1, is close to zero.
  • 4.4. Temperature insensitivity of this step at physiological pH, combined with a large pH dependence, probably denotes a property of Hb4, the Root effect Hb of trout blood.
  • 5.5. At pH 7.8, ΔH4 is about —4kcal/mol, a small value which may be attributed to the large release of Bohr protons that occurs at the last oxygenation step and corresponds to an endothermic process which opposes to the exothermic oxygenation of the haem.
  • 6.6. The ΔH4 value appears to have a large influence on the enthalpy for overall oxygenation.
  • 7.7. Results for ATP-free red cells are consistent with a mere increase in the intracellular pH and suggest that ATP has no specific effect at and above pHi ~ 7.7.
  • 8.8. Effects of temperature and pH on trout red blood cell isotherms emphasize the primary importance of the major component of trout blood, namely Hb4, in trout blood functional properties.
  相似文献   

6.
  • 1.1. Carp (Cyprinus carpio) were stressed to exercise by rolling in a respiration chamber. Ventilatory water flow rate, cardiac output and blood respiratory parameters were determined.
  • 2.2. During exercise, oxygen uptake increased about 3.5-fold and returned to pre-exercise level within 15 min.
  • 3.3. This exercise-stress resulted in no plasma acidosis and in no swelling of the erythrocytes.
  • 4.4. Ventilatory water flow rate increased 6-fold, whereas cardiac output increased 2-fold. Hence the ventilation-perfusion ratio increased during exercise.
  • 5.5. During exercise, arterial O2 content (CaO2) increased due to increases in O2 tension (PaO2), O2 saturation of hemoglobin (SaO2) and hemoglobin concentration (Hb). On the other hand, Pv̄O2 and Sv̄O2 remained at the resting levels but Cv̄O2 slightly increased due to an increase in Hb.
  • 6.6. Arterial-venous O2 difference (CaO2-Cv̄O2) increased by 38%, which was met by a much greater increase in CaO2 than Cv̄O2.
  相似文献   

7.
  • 1.1. Hemoglobin, hematological parameters, intraerythrocytic phosphates and whole blood Bohr effect of Pterygoplichthys multiradiatus, from the Amazon river, were studied in three different conditions: in their natural environment, acclimated to normoxia and acclimated hypoxia conditions.
  • 2.2. Nine anodal hemoglobin fractions were detected on starch gel electrophoresis. No qualitative differences in the Hb electrophoretic patterns were detected in the three studied groups.
  • 3.3. Hematocrit, hemoglobin concentration, MCV, MCHC and MCH were different among studied conditions.
  • 4.4. GTP was almost absent in the blood of animals in natural conditions and acclimated to hypoxia, but was present at a concentration similar to ATP in normoxic acclimated animals.
  • 5.5. There is a tendency for higher Hb-O2 affinity for hypoxic acclimated/acclimatized animals.
  相似文献   

8.
  • 1.1. Fish and snake immature erythrocytes were submitted to a comparative ultrastructural study, analysing changes in organelles involved in hemoglobin (Hb) biosynthesis.
  • 2.2. Iron uptake occurs probably via transferrin, and ferruginous compounds accumulate as siderosomes, taken as iron sources for heme biosynthesis, later on caught by a double lamella.
  • 3.3. Mitochondrial membrane of the inner camera differentiates to lamellated bodies that, sucessively, give rise to expansions for ferruginous material and globin chains captation, constituting prehemosomal vesicles, which become condensed vesicles, followed by prohemosomes.
  • 4.4. Through an internal membrane rearrangement, prohemosomes change to hemosomes wherein, hypothetically, heme and the globin chains assembly may occur.
  • 5.5. In both fish and snake erythroid cells, all stages for hemosomegenesis are similar to the stages found in erythroid cells of other vertebrate species, including humans, except that fish cells often present single organelles of still unknown function, void of internal membrane.
  • 6.6. Through electrophoresis of the respective supernatants obtained after osmotical lysis of the organellar fractions, it was shown that fish hemosomes contain three Hb patterns, while snake hemosomes present two patterns.
  相似文献   

9.
  1. Download : Download high-res image (121KB)
  2. Download : Download full-size image
Highlights
  • 18O/16O labeling N-glycopeptide quantification for 40-kDa band in HCC and LC.
  • •MRM verification of aberrant N-glycopeptides in healthy-HBV-LC-HCC cascade.
  • •TPLTAN205ITK (H5N5S1F1) and (H5N4S2F1) of IgA2 change in liver diseases.
  • •Variation in two N-glycopeptides abundance not caused by protein concentration.
  相似文献   

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.
  相似文献   

11.
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   

12.
  1. Download : Download high-res image (131KB)
  2. Download : Download full-size image
Highlights
  • •Proteogenomics and secretome comparison of human and zoonotic Staphylococcus aureus lineages.
  • •869 secreted proteins identified in eight S. aureus isolates of CC8, CC22 and CC398.
  • •CC398 lower secretion of surface proteins and higher secretion of hemolysins and exoenzymes.
  • •Regulatory differences in the secretomes could be linked to lower SigB activity in CC398.
  相似文献   

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. 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   

15.
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   

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

17.
  • 1.1. A variety of haematological parameters were determined in adult Dasyurus viverrinus.
  • 2.2. Haemoglobin and red cell counts were high with a very low mean cell volume.
  • 3.3. Basophils are absent but the eosinophils contain small numbers of basophilic granules which may indicate a dual role for this cell.
  • 4.4. “Ring Form” leucocytes are present.
  • 5.5. Three types of red cell picture could be identified, some animals showing large numbers of spherocytes, spicule cells, and inclusion bodies.
  • 6.6. These cells resemble those found in some inherited human haemolytic anaemias but there was no evidence of haemolysis in the animals.
  • 7.7. An alkali resistant haemoglobin component is present.
  相似文献   

18.
  • 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   

19.
  • 1.1. The level of carbonic anhydrase activity in the red cells was measured in sheep fetuses at different times after conception: 39, 56, 77, 90 and 140 days, the last being close to full term. Measurements were also made on blood from four of the mothers.
  • 2.2. There was a low level of the enzyme present in the 39 day fetuses (0.037 enzyme units (E.U.)/100 μg Hb) and its increase up to 90 days of gestation (0.19 E.U./100 μg Hb) had a form approximating exponential.
  • 3.3. The earliest levels were only 11% of the full term levels and only 4% of the adult levels previously reported.
  • 4.4. Even the earliest samples were of blood that was fetal rather than embryonic but these results are the earliest carbonic anhydrase activities reported in this mammal.
  相似文献   

20.
  1. Download : Download high-res image (78KB)
  2. Download : Download full-size image
Highlights
  • •Identification of the first evolutionary divergent sirtuin ScCobB2 in bacteria.
  • •Implementing a global quantitative succinylome between ΔScCobB2 and WT cells.
  • •ScCobB2 regulates S. coelicolor protein biosynthesis and carbon metabolism pathways.
  • •The divergent sirtuin enzymes are prevalent in other groups of Actinobacteria.
  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号