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21.
C Bengtsson L Hallberg H Noppa E Tibblin 《Acta morphologica Neerlando-Scandinavica》1979,17(2):133-143
Body weight, body height, skinfolds, circumferences and weight indices in a population sample of 1462 women in ages between 38 and 60 years are presented. Significant age differences were noted. High correlations (r) were found between body weight and triceps and subscapular skinfolds (0.62 and 0.72 respectively) and between body weight and arm, waist and buttock circumferences (0.75-0.88). Age differences were mostly noted between 46 and 50 years of age. After that age there was a comparatively greater increase of the waist circumference than of the buttock circumference, while triceps skinfold seemed to decrease after the age of 50 indicating an altered adipose tissue distribution from the extremities to the trunk with increasing age. When taking data from a previous study of body weight in the same population of women into consideration it seems that the age differences in body weight found in cross-sectional study like the present one may to a large extent depend on differences between different cohorts studied. 相似文献
22.
Summary The reasons behind the absence of the prawn Palaemon adspersus and the presence of P. squilla in rockpools and on bare sand bottoms were studied. Some maximal abundances in different habitats are given. Introduction experiments into natural and artificial rockpools and measurements of tolerance towards low oxygen levels showed that nocturnal hypoxia excluded P. adspersus which was significantly more sensitive to oxygen depletion. Respiration rates measured by the closed-bottle method showed no interspecific difference.On bare sand bottoms P. aspersus was probably excluded by predators, since predator exclusion experiments in cages and predator inclusion experiments in containers showed that P. adaspersus was more vulnerable to predation than P. squilla.The costs for being able to cope with a wide array of habitat in P. squilla are probably balanced by the benefits of access to habitats such as intertidal rockpools, very shallow bottoms and deeper sand bottoms. Tolerance towards abiotic factors extends its habitat range upwards into shallower waters, and tolerance towards biotic factors, i.e. predation, extends it downwards. 相似文献
23.
Lipoprotein lipase was purified from bovine milk and labeled with 125I. After intravenous injection to rats the labeled lipase rapidly disappeared from the blood. The initial half-life was about 1 min and more than 70% of the radioactivity was found in the liver at 10 min. 30 min after the injection about 10% of the injected radioactivity was present in acid-soluble form in blood, indicating that the enzyme had been rapidly degraded. Injection of asialofetuin, ribonuclease B or mannan in amounts known to block the hepatic receptors for glycoproteins with exposed galactose, N-acetylglucosamine or mannose residues did not retard the removal of the lipoprotein lipase. Thus, some other, as yet undefined, receptor is implicated. Lipoprotein lipase is known to bind to heparin and some related polysacchrides. Heparin injected before the enzyme delayed its removal and heparin injected after the enzyme caused an immediate increase in blood radioactivity, signifying return from tissues to blood of labeled enzyme. Lipoprotein lipase is present at the endothelium in several extrahepatic tissues and is rapidly turned over. Its presence in blood in appreciable amounts would cause a derangement of lipid transport. The efficient hepatic removal of the enzyme may thus serve an important physiological purpose in keeping the blood levels of this enzyme low. 相似文献
24.
Karl Enquist Mawritz Fransson Carolina Boekel Inger Bengtsson Lisa Lang Sofia Johansson IngMarie Nilsson 《Journal of molecular biology》2009,387(5):1153-354
To what extent do corresponding transmembrane helices in related integral membrane proteins have different membrane-insertion characteristics? Here, we compare, side-by-side, the membrane insertion characteristics of the 12 transmembrane helices in the adenosine triphosphate-binding cassette (ABC) transporters, P-glycoprotein (P-gp) and the cystic fibrosis transmembrane conductance regulator (CFTR). Our results show that 10 of the 12 CFTR transmembrane segments can insert independently into the ER membrane. In contrast, only three of the P-gp transmembrane segments are independently stable in the membrane, while the majority depend on the presence of neighboring loops and/or transmembrane segments for efficient insertion. Membrane-insertion characteristics can thus vary widely between related proteins. 相似文献
25.
The Population Study of Women in Gothenburg, Sweden is an ongoing prospective study of female residents who were recruited from the local registry in 1968–1969 when they were 38–60 years old. The data presented here were collected from 361 healthy women who underwent a baseline physical examination including a supplementary dietary history interview and returned for a second general health examination 6 years later. This report identifies a subgroup of 57 women who were sedentary during their leisure time and appear to have been particularly susceptible to gaining weight as a function of the fat content of their diets. Specifically, longitudinal analysis of body weights in the whole sample revealed a statistical interaction between leisure-time physical activity and habitual dietary fat intake (energy-%), as reported at the baseline examination, in the prediction of subsequent weight change. Further stratified analysis suggested that weight changes were significantly dependent on dietary fat intake among the sedentary women only. High energy intake also predicted weight gain in the sedentary group, although the predictive value for a high-fat diet was of marginal significance after adjusting for total energy consumption. These results suggest that sedentary recreational activity plus a low-fat diet may have a combined contribution to weight change that is not equivalent to the sum of the separate effects. Such a synergy between two modifiable lifestyle factors seems highly relevant for prevention of obesity. 相似文献
26.
Carina Mikolai Nadine Kommerein Alexandra Ingendoh‐Tsakmakidis Andreas Winkel Christine S. Falk Meike Stiesch 《Cellular microbiology》2020,22(8)
The host‐microbe relationship is pivotal for oral health as well as for peri‐implant diseases. Peri‐implant mucosa and commensal biofilm play important roles in the maintenance of host‐microbe homeostasis, but little is known about how they interact. We have therefore investigated the early host‐microbe interaction between commensal multispecies biofilm (Streptococcus oralis, Actinomyces naeslundii, Veillonella dispar, Porphyromonas gingivalis) and organotypic peri‐implant mucosa using our three‐dimensional model. After 24 hr, biofilms induced weak inflammatory reaction in the peri‐implant mucosa by upregulation of five genes related to immune response and increased secretion of IL‐6 and CCL20. Biofilm volume was reduced which might be explained by secretion of β‐Defensins‐1, ‐2, and CCL20. The specific tissue reaction without intrinsic overreaction might contribute to intact mucosa. Thus, a relationship similar to homeostasis and oral health was established within the first 24 hr. In contrast, the mucosa was damaged and the bacterial distribution was altered after 48 hr. These were accompanied by an enhanced immune response with upregulation of additional inflammatory‐related genes and increased cytokine secretion. Thus, the homeostasis‐like relationship was disrupted. Such profound knowledge of the host‐microbe interaction at the peri‐implant site may provide the basis to improve strategies for prevention and therapy of peri‐implant diseases. 相似文献
27.
Carina Donne Maurine Neiman James D. Woodell Martin Haase Gerlien Verhaegen 《Molecular ecology》2020,29(18):3446-3465
Non‐native invasive species are threatening ecosystems and biodiversity worldwide. High genetic variation is thought to be a critical factor for invasion success. Accordingly, the global invasion of a few clonal lineages of the gastropod Potamopyrgus antipodarum is thus both puzzling and has the potential to help illuminate why some invasions succeed while others fail. Here, we used SNP markers and a geographically broad sampling scheme (N = 1617) including native New Zealand populations and invasive North American and European populations to provide the first widescale population genetic assessment of the relationships between and among native and invasive P. antipodarum. We used a combination of traditional and Bayesian molecular analyses to demonstrate that New Zealand populations harbour very high diversity relative to the invasive populations and are the source of the two main European genetic lineages. One of these two European lineages was in turn the source of at least one of the two main North American genetic clusters of invasive P. antipodarum, located in Lake Ontario. The other widespread North American group had a more complex origin that included the other European lineage and two New Zealand clusters. Altogether, our analyses suggest that just a small handful of clonal lineages of P. antipodarum were responsible for invasion across continents. Our findings provide critical information for prevention of additional invasions and control of existing invasive populations and are of broader relevance towards understanding the establishment and evolution of asexual populations and the forces driving biological invasion. 相似文献
28.
Aline Vieira Santos Anna Carina Antunes e Defaveri Humberto Ribeiro Bizzo Rosane Aguiar da Silva San Gil Alice Sato 《In vitro cellular & developmental biology. Plant》2013,49(4):405-413
Varronia curassavica is cultivated for the production of an essential oil useful in the pharmaceutical industry for its strong anti-inflammatory effect. Despite a growing demand, only a few studies have evaluated alternative sources of obtaining plantlets or ways to increase the yield of essential oil from this species. Therefore, this study aimed to optimize the in vitro multiplication rate and analyze the histochemistry and sesquiterpene production potential of conventionally propagated V. curassavica plants, in vitro shoots, and acclimatized plants derived from in vitro shoots. For axillary bud proliferation, Murashige and Skoog medium was supplemented with 6-benzyladenine and thidiazuron alone or in combination with naphthalene acetic acid. Axillary bud proliferation was obtained from culture of nodal or apical segments on medium containing half-strength Murashige and Skoog salts without growth regulators. After 35 d of culture, an average of five buds developed per explant. Elongation and rooting of shoots also occurred in this medium. After the transfer of rooted plants to ex vitro conditions, 100% of the plantlets survived. Histochemical analysis of leaf tissue showed the presence of lipids, acidic lipids, essential oil, phenols, and flavonoids. The essential oils from conventionally propagated and acclimatized plants were extracted by hydrodistillation and analyzed using gas chromatography. The essential oil from acclimatized plants had a similar profile to that from ex vitro plants, but with a higher concentration of the anti-inflammatory compound alpha-humulene. 相似文献
29.
30.
Guilherme Loss-Morais Andreia Carina Turchetto-Zolet Matheus Etges Alexandro Cagliari Ana Paula K?rbes Felipe dos Santos Maraschin Márcia Margis-Pinheiro Rogério Margis 《Genetics and molecular biology》2013,36(1):74-86
Ribosome-inactivating proteins (RIPs) are enzymes that inhibit protein synthesis after depurination of a specific adenine in rRNA. The RIP family members are classified as type I RIPs that contain an RNA-N-glycosidase domain and type II RIPs that contain a lectin domain (B chain) in addition to the glycosidase domain (A chain). In this work, we identified 30 new plant RIPs and characterized 18 Ricinus communis RIPs. Phylogenetic and functional divergence analyses indicated that the emergence of type I and II RIPs probably occurred before the monocot/eudicot split. We also report the expression profiles of 18 castor bean genes, including those for ricin and agglutinin, in five seed stages as assessed by quantitative PCR. Ricin and agglutinin were the most expressed RIPs in developing seeds although eight other RIPs were also expressed. All of the RIP genes were most highly expressed in the stages in which the endosperm was fully expanded. Although the reason for the large expansion of RIP genes in castor beans remains to be established, the differential expression patterns of the type I and type II members reinforce the existence of biological functions other than defense against predators and herbivory. 相似文献