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1.
The aim of this work was to evaluate the physical development and nutritional status, the nutrition habits as well as level of physical activity of boys and girls in relation to the socio-economic status of their families. The study was conducted on a group of 529 boys and 535 girls aged 7-16 years from Swietokrzyskie Province in Poland. Boys and girls from high SES families had the greatest body height, BMI, upper arm muscle area, as well as upper arm fat tissue area, while the lowest values of these features occurred among those studied coming from families of a low SES. The higher the family SES, the higher habitual frequency of consuming vegetables and fruit as well as fish. The diet of children coming from higher SES families was also linked with a higher total protein content as well as animal protein, all analysed minerals and some vitamins, but there were no significant differences of energetic value in daily food rations as well as fat content. The longer time spent on some sedentary activities was connected with a higher family SES. The girls coming from a high status families also declared a higher level of physical activity, whereas such relationship was not observed among boys. A more rational set of nutritional habits observed among children from a higher SES families can be the basic reason for their higher advancement in development. A shorter time devoted to sedentary activities is assumed to be the main cause of a smaller relative body mass and less obesity among girls and boys from low SES families.  相似文献   

2.
The mRNA coding for the ACTH-β-lipotropin precursor from a human ectopic ACTH-producing thymic carcinoid was identified by blot hybridization analysis with the bovine cDNA as a probe. The mRNA from the tumor had the same length (approximately 1,100 nucleotides) as that from the human pituitary. An additional hybridization-positive RNA species of a larger size was found in the tumor. Cell-free translation of the mRNA from the tumor as well as from the pituitary yielded a product with an apparent molecular weight of 38,000 that was reactive both with antibody to ACTH and with antibody to β-endorphin.  相似文献   

3.
Peroxidases are ubiquitous enzymes found in virtually all green plants, many fungi and aerobic bacteria. The isozymic heterogeneity of peroxidases appears to result from de novo synthesis, as well as an array of physiological/ecological determinants including hormones, light, gravity, and infection. Homologies among isoperoxidases from the same species are largely distinguished by the isoelectric point and as well as by protein sequence data. The basic and acidic peroxidases from a number of angiosperms show a greater functional and structural relationship within rather than between these groups. Peroxidases have phylogenetically-correlated similarities based on the chemical nature and redox potentials of the substrates which they can oxidize. Peroxidases often increase as a response to stress, and one of the principle roles of peroxidase appears to be cellular protection from oxidative reactions imposed on all photosynthetic plants. The relationships among the peroxidases, IAA and lignification emerge as a particular adaptation of vascular plants to the land environment. The great catalytic versatility of peroxidase as its predominant character and, therefore, no single major role need necessarily exist for this multifaceted enzyme.  相似文献   

4.
Abstract

Multiple‐cause mortality data were used to examine changing patterns of mortality between 1950 and 1979 in American Samoa. This period coincided with a transition from infectious to chronic diseases as the primary causes of death. The available data indicate that as mortality rates from infections declined, the first chronic disease to increase in frequency was cancer. The absence of a lag period suggests that increased cancer mortality may be a consequence of life extension in the presence of modernization. In contrast, mortality rates from cardiovascular diseases tended to increase only after a lag period. As mortality from infections declined, ischemic heart disease replaced infections as the leading cause of death, in either a total‐mentions or an underlying‐cause model of mortality. The transition to degenerative disease mortality in American Samoa was neither as rapid nor as simple as a tabulation by underlying cause of death indicates. Patterns of change were interrelated.  相似文献   

5.
Lysozymes with different molecular weights were isolated from homogenates of ticks or Ixodoidea with a procedure based on specific sorption of the enzyme by chitin. Lysozymes with a molecular weight of 13,800 were isolated from O. moubata, O. papillipes and A. lahorensis and lysozymes with a molecular weight of 15,000 were isolated from H. asiaticum and I. persulcatus. Micrococci and staphylococci proved to be the most sensitive to the lysozymes. E. coli and Salmonella spp. were less sensitive. The activity of the lysozymes from O. moubata, O. papillipes and A. lahorensis was 2 to 4 times as high as that of the yolk lysozyme and 4 to 8 times as high as that of the lysozymes from H. asiaticum and I. persulcatus. The activity of the yolk lysozyme was 2 or more times as high as that of the lysozymes from H. asiaticum and I. persulcatus. The lysozymes were resistant to heating in acid media. In alkaline media a marked loss of the activity was observed.  相似文献   

6.
The sensitivities of PDE-4 enzymes from smooth muscle and inflammatory cell sources from different species to a range of structurally diverse compounds were compared. All inflammatory cell PDE-4 sources displayed good crosscorrelations in their sensitivity to inhibition by these compounds. Similarly, PDE-4 enzymes from smooth muscle sources were well-correlated; however, there was no crosscorrelation between PDE-4 from smooth muscle sources and those of inflammatory cell sources, possibly reflecting differences in subcellular location of enzymes as well as subtype expression. The present study concludes that PDE-4 preparations from smooth muscle sources as well as those from inflammatory cell sources may be used to model the potential smooth muscle cell relaxing properties and anti-inflammatory properties of a compound in relation to human asthma.  相似文献   

7.
Ganoderic acids (GAs) are oxygenated lanostane-type triterpenoids from the traditional medicinal mushroom Ganoderma lucidum and of significant biological activities. Although a ganoderic acid 3-hydroxy-lanosta-8,24-dien-26-oic acid (HLDOA) was found to be biosynthesized from lanosterol, further post-modification of HLDOA is yet unclear. In this work, by using HLDOA as the substrate and a crude enzyme from G. lucidum as the biocatalyst, we observed a new peak in liquid chromatography from the reaction system. The product was purified and identified to be 3-oxo-lanosta-8,24-dien-26-oic acid (OLDOA), which may be converted from HLDOA by a putative dehydrogenase of G. lucidum. The work is useful to future manufacture of GAs as well as their biosynthetic pathway elucidation.  相似文献   

8.
The bovine J blood group substance exists as a glycosphingolipid (ceramide deca-hexoside as well as ceramide dodecahexoside) and as a glycoprotein. The lipidic form occurs in erythrocyte membranes, both forms are found in serum. The lipidic J substances were isolated from erythrocytes and from serum, and identified by thin-layer chromatography with lipidic J substances isolated from spleen. The glycoprotein nature of the non-lipidic J of serum was evident by pronase-catalysed hydrolysis yielding J-active glycopeptides of lower molecular weights. The lipidic J was completely extracted from lyophilized stroma with chloroform/methanol. From lyophilized serum, however. it was completely extracted only in the presence of water, indicating different binding partners in serum and in erythrocyte membranes. The J lipid was incorporated as intact molecule into the erythrocyte membrane by a simple incubation technique. The incorporation was inhibited by various glyc-erophospholipids (called blockers). The J glycoprotein could not be transferred to the erythrocyte membrane. Three methods are descrjbed which are suitable for the preparation of a blocker-free fraction enriched with J lipids from J-positive serum.  相似文献   

9.
In this work, a novel technique for continuous purification of biologics from a crude feedstock is demonstrated with equipment referred to as Fluidized Bed Adsorption System (FBRAS). The development and validation of such unit operations were performed utilizing lysozyme as a model protein and Relisorb™ SP405/EB as a carrier. The performance of FBRAS to carry out combined clarification and purification was evaluated by capturing of antifungal peptides directly from the lysed broth. The novel technique reduced the number of process unit operations from six to three without having an impact on purity. Overall productivity increased by 250% in comparison to the existing downstream processing routine.  相似文献   

10.
Food fortification has been shown to be an effective strategy to overcome iron malnutrition. When a new iron compound is developed for this purpose, it must be evaluated from a nutritional and technological point of view before adding it into foods. In this way, we have evaluated ferrous gluconate stabilized by glycine as a new iron source to be used in wheat flour fortification. We performed biological studies in rats as well as sensory perceptions by human subjects in wheat flour fortified with this iron source. The productions of pentane as a rancidity indicator as well as the change of the sensorial properties of the biscuits made with stabilized ferrous gluconate-fortified wheat flour were negligible. Iron absorption in water from this iron source was similar to the reference standard ferrous sulfate. Nevertheless, because of the phytic acid content, iron absorption from fortified wheat flour decrease 40% for both iron sources. The addition of zinc from different sources did not modify iron absorption from ferrous sulfate and stabilized ferrous gluconate in water and wheat flour. The iron absorption mechanism as well as the biodistribution studies demonstrate that the biological behavior of this iron source does not differ significantly from the reference standard. These results demonstrate that the iron source under study has adequate properties to be used in wheat flour fortification. Nevertheless, more research is needed before considering this iron source for its massive use in food fortification.  相似文献   

11.
The L11 ribosomal protein from Thermus thermophilus (TthL11) has been overproduced and purified to homogeneity using a two-step purification protocol. The overproduced protein carries a similar methylation pattern at Lys-3 as does its homolog from Escherichia coli. Chymotrypsin digested only a small part of the TthL11 protein and did not cleave TthL11 into two peptides, as in the case of EcoL11, but produced only a single N-terminal peptide. Tryptic digestion of TthL11 also produced an N-terminal peptide, in contrast to the C-terminal peptide obtained with L11 from Bacillus stearothermophilus. The recombinant protein forms a specific complex with a 55-nt 23S rRNA fragment known to interact with members of the L11 family from several organisms. Cooperative binding of TthL11 and thiostrepton to 23S rRNA leads to an increased protection of TthL11 from tryptic digestion. The similar structural and biochemical properties as well as the significant homology between L11 from E. coli and B. stearothermophilus with the corresponding protein from Thermus thermophilus indicate an evolutionarily conserved protein important for ribosome function.  相似文献   

12.
The possibility of using microorganisms to clean oiled iron scale of metallurgical production was investigated with the goal of recuperation. A stable microbial association growing on mineral oil as the sole carbon source was isolated from a sample from oiled iron scale taken directly from a metallurgical plant. For microbial cultures isolated from this association, the taxonomic position, as well as their morphological and cultural characteristics, were determined. The microorganisms belonged to the genera Luteimonas, Alcanivorax, Flavobacterium, and Pseudomonas. Microbial associations oxidizing mineral oil were found to contain some microorganisms incapable of its utilization, which stimulated the hydrocarbon-oxidizing microflora. Application of the isolates, as well as of the strains from microbial collections, resulted in a 58% decrease in residual oil content in treated samples of the oiled iron scale.  相似文献   

13.
The photosynthetic response, defined as the initial slope of the photosynthesis-irradiance curve, was determined spectrally (every 25 nm from 400 to 675 nm; 25 nm half-maximum bandpass) for natural phytoplankton populations from High Arctic, Grand Banks and Sargasso Sea waters, as well as for populations living in the lower margin of sea ice off Newfoundland, All spectra were similar in shape with a maximum at 425–450 nm, a broad shoulder to 550 nm, a valley from 600 to 650 nm and a rise at 675 nm. The error resulting from the use of spectrally averaged initial slope to predict photosynthesis under different optical and fluid dynamical conditions at sea is discussed.  相似文献   

14.
A nuclease that could be recovered from the supernatant of cultures, as well as from cell-free extracts, of the cyanobacterium Anabaena sp. PCC 7120 was identified as a 29 kDa polypeptide by its ability to degrade DNA after electrophoresis in DNA-containing SDS-polyacrylamide gels. Some clones of a gene library of strain PCC 7120 established in Escherichia coli were found to produce the 29 kDa nuclease. The nucA gene encoding this nuclease was subcloned and sequenced. The deduced polypeptide, NucA, had a molecular weight of 29,650, presented a presumptive signal peptide in its N-terminal region and showed homology to the products of the nuc gene from Serratia marcescens and the NUC1 gene from Saccharomyces cerevisiae. The NucA protein from Anabaena itself, or from the cloned nucA gene expressed in E. coli, catalysed the degradation of both RNA and DNA, had the potential to act as an endonuclease, and functioned best in the presence of Mn2+ or Mg2+. An Anabaena nucA insertional mutant was generated which failed to produce the 29 kDa nuclease.  相似文献   

15.
Alginate is a major cell wall polymer of brown algae. The precursor for the polymer is GDP-mannuronic acid, which is believed to be derived from a four-electron oxidation of GDP-mannose through the enzyme GDP-mannose dehydrogenase (GMD). So far no eukaryotic GMD has been biochemically characterized. We have identified a candidate gene in the Ectocarpus siliculosus genome and expressed it as a recombinant protein in Escherichia coli. The GMD from Ectocarpus differs strongly from related enzymes in bacteria and is as distant to the bacterial proteins as it is to the group of UDP-glucose dehydrogenases. It lacks the C-terminal ~120 amino acid domain present in bacterial GMDs, which is believed to be involved in catalysis. The GMD from brown algae is highly active at alkaline pH and contains a catalytic Cys residue, sensitive to heavy metals. The product GDP-mannuronic acid was analyzed by HPLC and mass spectroscopy. The K(m) for GDP-mannose was 95 μM, and 86 μM for NAD(+). No substrate other than GDP-mannose was oxidized by the enzyme. In gel filtration experiments the enzyme behaved as a dimer. The Ectocarpus GMD is stimulated by salts even at low molar concentrations as a possible adaptation to marine life. It is rapidly inactivated at temperatures above 30 °C.  相似文献   

16.
The illness-death model is the simplest multistate model where the transition from the initial state 0 to the absorbing state 2 may involve an intermediate state 1 (e.g., disease relapse). The impact of the transition into state 1 on the subsequent transition hazard to state 2 enables insight to be gained into the disease evolution. The standard approach of analysis is modeling the transition hazards from 0 to 2 and from 1 to 2, including time to illness as a time-varying covariate and measuring time from origin even after transition into state 1. The hazard from 1 to 2 can be also modeled separately using only patients in state 1, measuring time from illness and including time to illness as a fixed covariate. A recently proposed approach is a model where time after the transition into state 1 is measured in both scales and time to illness is included as a time-varying covariate. Another possibility is a model where time after transition into state 1 is measured only from illness and time to illness is included as a fixed covariate. Through theoretical reasoning and simulation protocols, we discuss the use of these models and we develop a practical strategy aiming to (a) validate the properties of the illness-death process, (b) estimate the impact of time to illness on the hazard from state 1 to 2, and (c) quantify the impact that the transition into state 1 has on the hazard of the absorbing state. The strategy is also applied to a literature dataset on diabetes.  相似文献   

17.
The primary structure of the larger subunit of the soluble guanylyl cyclase from bovine lung, which catalyzes the formation of cyclic GMP from GTP, has been determined. Two clones, isolated from two bovine libraries yielded a total of 3261 bp with a coding region of 2073 bp. The open reading frame encodes a protein of 691 amino acids and a molecular mass of 77,500. The deduced amino acid sequence reveals regions which are, to a large extent, homologous to the sequence of the smaller subunit of the enzyme as well as to the sequences of other gyanylyl and adenylyl to a large extent, homologous to the sequence of the smaller subunit of the enzyme as well as to the sequences of other gyanylyl and adenylyl cyclases.  相似文献   

18.
Photosystem I (PSI) has been isolated from mesophyll chloroplasts of mature maize leaves. The isolated PSI (PSI-200) was used as starting material for preparing an antenna-depleted core (PSI-100). Both of these preparations appear to be quite analogous to PSI complexes isolated from other plant tissue sources, such as those from C3 plants, as judged from NADP photoreduction assays, immunoblotting, and the ability of the complexes to form a covalent crosslinked product with spinach plastocyanin. The study suggests that the PSI complex from a C4 plant is similar to that isolated from a C3 plant in that both contain the plastocyanin docking protein although the apparent molecular weight of these respective subunits differ slightly.  相似文献   

19.
A new kind of psychiatric facility to deal with patients returning to their community from a state hospital or with patients newly ill and treatable locally, combines a number of features in the interests of economy and enhanced effectiveness. Its economy arises from: (1) The exclusion of bed-patient and security-ward care for patients not in need of them; (2) a shortened hospital stay resulting from rapid treatment procedures (electroconvulsion, brief psychotherapy and drug therapy); (3) a flexible shifting to outpatient or day care as soon as practicable. Enhanced effectiveness of therapy arises from earlier discharge from state hospitals, earlier treatment of patients from the community, as well as comprehensive utilization of multiple therapeutic modalities.  相似文献   

20.
Immunoglobulin heavy chain mRNA was purified from immunoprecipitated polysomes derived from the mouse myeloma tumor, MOPC-31C. The purified mRNA migrated predominantly as a single band upon polyacrylamide gel electrophoresis in 98% formamide and the molecular weight of this mRNA was calculated to be 700,000. This mRNA was as active as the purified light chain mRNA when it was employed as a template in a cell-free protein synthesizing system from wheat germ. The translation product had a molecular weight of 55,000 daltons, and migrated slightly faster than mature heavy chain upon polyacrylamide gel electrophoresis in sodium dodecylsulfate. The protein synthesized by the direction of this mRNA was shown to yield tryptic peptides corresponding to those derived from the mature heavy chain protein except that one missing peptide was replaced by another additional peptide. DNA complementary to the mRNA was synthesized by RNA-dependent DNA polymerase from avian myeloblastosis virus. Hybridization kinetic analysis between the heavy chain mRNA and its complementary DNA indicated that the RNA was essentially homogenous with rabbit globin mRNA as a standard.  相似文献   

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