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1.
Zinc (Zn) and copper (Cu) are essential trace elements in people, being required for functional activity of several enzyme systems. In this study, we determined Cu and Zn concentrations in the serum of 105 healthy children randomly selected, aged 3–14 yr, residing in a region of Greece (Thrace), and we investigated their association with children's gender, age, height, weight, and nutritional habits. The mean levels of Zn and Cu were 15.01±2.95 μmol/L and 26.18±5.47 μmol/L, respectively, with no significant difference between boys and girls. A significant positive correlation was found between age and Zn levels, and a negative one was found between age and Cu levels. Both Zn and Cu levels tended to increase with height, whereas Zn levels significantly decreased with increasing body mass indent (BMI). The consumption of meat, milk, and eggs were independent determinants for higher Zn levels, and the consumption of legumes and fruits were independent determinants for higher Cu levels. A significant negative correlation was found between Zn and Cu levels. In conclusion, our study, the first one evaluating the serum status of Cu and Zn in healthy Greek children, identified significant correlations of Zn and Cu levels with their age, height, BMI, and nutritional habits.  相似文献   

2.
Problems of quick adaptation of the gastric glands of wrestlers to threshold-power bicycle ergometer exercise during sports and postsports ontogeny are discussed. It has been established that threshold-power bicycle ergometer exercise may suppress, stimulate, or not affect the secretion of H2O, HCl, and pepsinogen. The pattern of these shifts is aimed at optimizing the actual level of protein hydrolysis; it depends on the age, sports experience, and qualification and is correlated with the body weight.  相似文献   

3.
We determined the independent factors that reflect the fundamental characteristics of the functional state (FS) in adolescents aged 13–14 years (n = 162): the sympathetic regulation and parasympathetic regulation of FS, physical working capability; the efficiency of cognitive performance; the hemodynamic basis of cognitive activity; nonspecific resistance to upper respiratory tract infections. Using the systematic approach, we investigated the physiological basis of these factors and determined the indices suitable for estimating the FS of adolescents at different stages of puberty. We observed progressive dynamics of FS parameters related to factors listed above in boys of the same chronological age at different puberty stages. Beginning from stage II to stage IV, we observed a heterochronic and nonlinear decrease in the tension of system of autonomic FS regulation, an increase in the efficiency of cognitive activity and its hemodynamic supply, as well as an improvement of anaerobic working capability.  相似文献   

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Several studies have reported a characteristic "positive illusory bias" in the self-evaluation of children with ADHD. However, results are controversial. The aim of the present study was to investigate whether children with ADHD aged 8 to 10 years can rate their self-regulatory skills accurately when assessed with an age appropriate instrument. Twenty-seven children with ADHD and 27 matched normal control children completed the Self-rating Scale of Self-regulatory Function (SelfReg), a new rating scale that has been specifically designed for this age group. As expected, children with ADHD rated themselves significantly more dysfunctional than control children. In most domains, self-ratings of children with ADHD did not diverge from parent and teacher ratings to a greater extent than self-ratings of control children, although overall results indicated a moderate tendency toward a positive bias. When a cluster analysis based on discrepancies between children's and adults' evaluations was carried out, three groups with different self-rating patterns emerged: A "positive bias" group containing exclusively children with ADHD, a "negative bias" group containing both children with ADHD and control children, and the largest group of accurate self-raters which also included children from both diagnostic groups. It is concluded that overly positive self-judgments are not a ubiquitous finding in ADHD, but may be confined to a specific subgroup of children whose specific characteristics remain to be determined.  相似文献   

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《Comptes Rendus Palevol》2008,7(8):645-656
This study analyses the carnivore component of African fossil faunas from three time slices: 7–5 Ma, 4–3 Ma, and 2.5–1.2 Ma, using cluster analysis and principal coordinate analysis (PCO) of presence/absence data on genera. The faunas mostly cluster by time slice, with the exception of Laetoli (Tanzania) and Ahl al Oughlam (Morocco), which differ from all other faunas. The separation during the Late Miocene of a Chado–Libyan bioprovince from the remainder of Africa is supported. No such distinctions are present in the other time slices. Taxonomic distance is not generally correlated with geographic distance, though if Langebaanweg is removed from the 7–5 Ma time slice, the correlation at that time is significant. Comparison of these paleontological results with phylogeographic studies of modern species leads to some general comments on the analytic power of the fossil record with regard to interregional migrations.  相似文献   

9.
AimIL-18 is hypothesized to destabilise atherosclerotic plaques, leading to thrombotic events and epidemiologic studies suggest that IL-18 may increase risk of CHD or CVD.We examined prospective associations between levels of serum IL-18 and new CHD and stroke events in older men and women from a general population.MethodsA case-control study was nested within a prospective cohort of men and women aged 60–79 years recruited from general practices in 25 British towns in 1998–2000 and followed-up for 7.5 years for fatal and non-fatal MI and stroke. Baseline IL-18 was measured in stored serum samples of incident cases of MI (n = 364) or stroke (n = 300) and two controls per case.ResultsGeometric mean IL-18 levels were higher among the 364 MI cases than the 706 controls; 417.84 pg/mL (IQR 316.25, 537.44) compared to 386.90 pg/mL (IQR 296.54, 482.33), p(difference) = 0.002. IL-18 was positively associated with adverse lipid and inflammatory profiles. Men and women in the top third of baseline IL-18 levels had an age and sex-adjusted odds ratio (OR) for MI of 1.31 (95%CI 0.92, 1.85) compared with those in the lowest third; this attenuated to 1.05 (95%CI 0.72, 1.53) after additional adjustment for established vascular and inflammatory risk factors. Each doubling of IL-18 level was associated with an increased OR for MI 1.34 (95%CI 1.04, 1.72), which was attenuated on adjustment for established vascular and inflammatory risk factors; 1.09 (95%CI 0.83, 1.44).Geometric mean IL-18 levels did not differ between stroke cases and controls. The OR for stroke associated with the highest compared to the lowest tertile of IL-18 was 1.24 (95%CI 0.84, 1.84). Results for MI and stroke did not differ by presence of pre-existing CVD, gender or age.ConclusionsCirculating IL-18 levels were strongly associated with a range of established and novel risk factors but were not independently associated with risk of MI or stroke in our study.  相似文献   

10.
Microbiological and enzyme activities of extrazonal taiga-steppe soils in the lower reaches of the Kolyma River have been studied for the first time. Contrary to north-taiga cryometamorphic soils, predominating in the area, microbial cenoses under herb–sedge petrophytic and grass–sagebrush–herb thermophytic steppes are characterized by features typical for arid soils. The saturation of the soil profile with microorganisms is greater, and the development of actinomycetes is more intensive. The enzyme complex is characterized by high activity of dehydrogenases.  相似文献   

11.
We studied the frequency and amplitude properties of the EEG μ rhythm in children (n = 38) aged 4–14 years under the condition of visual fixation (VF) on a video image of a computer mouse, as well as the parameters of its desynchronization during the tasks involving self-controlled performance, observation, imitation, and auditory recognition of the hand circular movements (SPM, OM, IM, and ARM, respectively) with a computer mouse. We observed age-related increment in the modal frequency of μ rhythm in loci C 3 and C z. During the SPM process, a significant decrease in the amplitude of μ rhythm was found in loci C 3 (26.7%) and C z (10.3%); during the OM, in locus C z only (9.9%). The effects of the μ rhythm desynchronization during both self-paced and observed movements might be an evidence of well-developed neural matching mechanisms that provide the processes of performing and observing similar actions in children aged 4 to 14 years. During the IM, the desynchronization of μ rhythm was significant in loci C 3 (27.4%) and C z (15.3%). We hypothesize that the statistically significant increase (from SPM to IM) in the depression of μ rhythm in locus C z is likely to be an effect of a social gaming context common for the situations when children imitate the movements of adults. The index of desynchronization of μ rhythm under the studied conditions did not depend on the age of children. Possible relations of identified modulations of the μ rhythm to the activity of the mirror neuron system were also discussed.  相似文献   

12.
Ruthenium-based compounds have intriguing anti-cancer properties, and some of these novel compounds are currently in clinical trials. To continue the development of new metal-based drug combinations, we coupled ruthenium (Ru) with the azole compounds ketoconazole (KTZ) and clotrimazole (CTZ), which are well-known antifungal agents that also display anticancer properties. We report the activity of a series of 12 Ru–KTZ and Ru–CTZ compounds against three prostate tumor cell lines with different androgen sensitivity, as well as cervical cancer and lymphoblastic lymphoma cell lines. In addition, human cell lines were used to evaluate the toxicity against non-transformed cells and to establish selectivity indexes. Our results indicate that the combination of ruthenium and KTZ/CTZ in a single molecule results in complexes that are more cytotoxic than the individual components alone, displaying in some cases low micromolar CC50 values and high selectivity indexes. Additionally, all compounds are more cytotoxic against prostate cell lines with lower cytotoxicity against non-transformed epidermal cell lines. Some of the compounds were found to primarily induce cell death via apoptosis yet weakly interact with DNA. Our studies also demonstrate that the cytotoxicity induced by our Ru-based compounds is not directly related to their ability to interact with DNA.  相似文献   

13.
Adolescence constitutes a period of nutritional vulnerability due to increased dietary requirements for growth and development and special dietary habits. A pilot trial was performed to evaluate the dietary calcium utilization among a sample of Spanish boys on their usual diets, in which the calcium intake and consumption of dairy products were as well examined. Nutrient and food intake was recorded using a 24-h dietary recall and a 2-d food consumption record for 21 subjects aged 11-14 years. Dietary calcium utilization was assessed by means of calcium intake in food and calcium output in faeces and urine as measured by flame atomic absorption spectrophotometry. Overall intake of dairy products was 399.3 +/- 22.1 g/d, and the single most consumed item was milk (72% of the total). An inverse relationship was found between dairy product consumption at breakfast (55% of the total) and BMI (p = 0.016, r = -0.5168). Dairy products contributed the majority of dietary calcium (66.9%). Mean calcium intake was 881.7 +/- 39.9 mg/d, 88% of the recommended value for Spanish adolescents. Net calcium absorption (271.7 +/- 51.7 mg/d) and retention (170.6 +/- 50.9 mg/d) seemed not to be sufficient to meet growth demands during puberty. The results shown that adolescents of the study absorbed 31% of dietary calcium and retained nearly 20% of the total intake, but dietary calcium intake and consumption of dairy products failed to meet recommended values. Optimizing calcium intake is of crucial importance among adolescents, to maximize calcium retention and to help prevent osteoporosis in later life.  相似文献   

14.
We determined in situ feeding rates of three co-occurring coastal mysid species using [methyl-3H]-thymidine-labelled algal detritus (Lessonia corrugata), NaH14CO3-labelled phytoplankton (Isochrysis galbana) and zooplankton (Artemia sp. nauplii). All three species showed a wide and overlapping range of feeding rates on the three food types, suggesting they were broadly omnivorous. However, selectivity studies often showed a strong preference for animal prey. Although there was an overlap in the types of food the mysids ingested, some degree of feeding niche partitioning was demonstrated. Paramesopodopsis rufa tended to be more carnivorous, Tenagomysis tasmaniae fed least on zooplankton and phytoplankton, and largely on algal detritus, and Anisomysis mixta australis ingested few zooplankters, and moderate amounts of algal detritus and phytoplankton. Handling editor: P. Viaroli  相似文献   

15.
International Journal of Peptide Research and Therapeutics - The antioxidant capacities of rice bran protein hydrolysates (RBPH) obtained by in vitro gastro-intestinal (GI) digestion by...  相似文献   

16.
Whole-ecosystem interactions and feedbacks constrain ecosystem responses to environmental change. The effects of these constraints on responses to climate trends and extreme weather events have been well studied. Here we examine how these constraints respond to changes in day-to-day weather variability without changing the long-term mean weather. Although environmental variability is recognized as a critical factor affecting ecological function, the effects of climate change on day-to-day weather variability and the resultant impacts on ecosystem function are still poorly understood. Changes in weather variability can alter the mean rates of individual ecological processes because many processes respond non-linearly to environmental drivers. We assessed how these individual-process responses to changes in day-to-day weather variability interact with one another at an ecosystem level. We examine responses of arctic tundra to changes in weather variability using stochastic simulations of daily temperature, precipitation, and light to drive a biogeochemical model. Changes in weather variability altered ecosystem carbon, nitrogen, and phosphorus stocks and cycling rates in our model. However, responses of some processes (e.g., respiration) were inconsistent with expectations because ecosystem feedbacks can moderate, or even reverse, direct process responses to weather variability. More weather variability led to greater carbon losses from land to atmosphere; less variability led to higher carbon sequestration on land. The magnitude of modeled ecosystem response to weather variability was comparable to that predicted for the effects of climate mean trends by the end of the century.  相似文献   

17.
This study aimed to assess the relationship of 3 spectrin repeat containing nuclear envelope protein 1 (SYNE1) and 4 KH domain containing RNA binding (QK1) single nucleotide polymorphisms (SNPs), their haplotypes, gene-gene (G × G), gene-environment (G × E) interactions and hypercholesterolaemia (HCH) and hypertriglyceridaemia (HTG) in the Chinese Maonan minority. The genetic make-up of the SYNE1-QK1 SNPs in 1932 unrelated subjects (normal, 641; HCH, 649; and HTG, 642) was obtained by next-generation sequencing technologies. The genotypic frequencies of following SNPs were suggestively distinctive between the control and HCH groups (rs2623963, rs7745725, rs9459317, rs16897566), or between the control and HTG groups (rs2623963, rs1358317, rs7745725, rs1923608, rs16897566 SNPs; P < .05, respectively). Multiple-locus linkage disequilibrium analysis indicated that the identified SNPs were not inherited independently. Several haplotypes and gene-gene interaction haplotypes among the detected SNPs may be related with an increased morbidity of HCH (C-G-A, C-G-G and C-G-G-T-C-A-T) and HTG (C-G-G, G-T-G-C, C-G-G-G-T-G-C and C-G-G-T-C-A-T), whereas others may be related with an decreased risk of HCH (G-A-A, G-C-A-T, C-A-A-T-C-A-T and G-A-A-G-C-A-T) and HTG (G-A-A, G-C-A-T, C-A-A-T-C-A-T and G-A-A-G-C-A-T). The association evaluation based on haplotypes and gene-gene interactions could improve the power of detecting the risk of dyslipidaemia than anyone of SNP alone. There was significant three-locus model involving SNP-SNP, haplotype-haplotype/environment and G × G interactions (P < .05-0.001) that were detected by GMDR in HCH and HTG groups. Different interactions between genetic and environmental factors would produce different redundancy or synergy effects on the morbidity of HCH and/or HTG.  相似文献   

18.
Japan’s rapid urbanisation over the last 50 years has resulted in land use and lifestyle changes, all of which are likely to have changed the quality of river water, and consequently the wetland and coastal environment. We examined changes in river water quality over this period by means of a review of previous studies. Around the 1950s, the weighted average of chloride using discharge of Japan’s 30 major rivers was 6.1 mg/l while in the 2000s it was 11.3 mg/l. Because there were no significant changes in the natural conditions, we have attributed the increase to the urbanisation of the last 50 years. Nitrate levels in the mountain streams of southern Japan have increased, particularly in the western part of the Kanto region. As this area is located on the leeward side of the Tokyo Metropolitan Area, depositions from aerosols are thought to be the main cause of the increased nitrate concentration. These two findings suggest that certain uses of land may affect river water quality differently over time, and that changes in land use may also affect river water quality in remote areas.  相似文献   

19.
Passive forest restoration can buffer the effects of habitat loss on biodiversity. We acoustically surveyed aerial insectivorous bats in a whole-ecosystem fragmentation experiment in the Brazilian Amazon over a 2-year period, across 33 sites, comprising continuous old-growth forest, remnant fragments, and regenerating secondary forest matrix. We analyzed the activity of 10 species/sonotypes to investigate occupancy across habitat types and responses to fragment size and interior-edge-matrix (IEM) disturbance gradients. Employing a multiscale approach, we investigated guild (edge foragers, forest specialists, flexible forest foragers, and open space specialists) and species-level responses to vegetation structure and forest cover, edge, and patch density across six spatial scales (0.5–3 km). We found species-specific habitat occupancy patterns and nuanced responses to fragment size and the IEM disturbance gradient. For example, Furipterus horrens had lower activity in secondary forest sites and the interior and edge of the smallest fragments (1 and 10 ha) compared to continuous forest, and only two species (Pteronotus spp.) showed no habitat preference and no significant responses across the IEM and fragment size gradients. Only the Molossus sonotype responded negatively to vegetation structure. We uncovered no negative influence of forest cover or edge density at guild or species-level. Our results indicate that reforestation can buffer the negative effects of fragmentation and although these effects can still be detected in some species, generally aerial insectivorous bats appear to be in recovery after 30 years of passive forest restoration. Our findings reinforce the need to protect regenerating forests while conserving vast expanses of old-growth forest.  相似文献   

20.
Communities of insect herbivores are thought to be structured mainly by indirect processes mediated by shared natural enemies, such as apparent competition. In host–parasitoid interaction networks, overlap in natural enemy communities between any pair of host species depends on the realized niches of parasitoids, which ultimately depend on the foraging decisions of individuals. Optimal foraging theory predicts that egg-limited parasitoid females should reject small hosts in favour of future opportunities to oviposit in larger hosts, while time-limited parasitoids are expected to optimize oviposition rate regardless of host size. The degree to which parasitoids are time- or egg-limited depends in part on weather conditions, as this determines the proportion of an individual''s lifespan that is available to foraging. Using a 10-year time series of monthly quantitative host–parasitoid webs, we present evidence for host-size-based electivity and sex allocation in the common secondary parasitoid Asaphes vulgaris. We argue that this electivity leads to body-size-dependent asymmetry in apparent competition among hosts and we discuss how changing weather patterns, as a result of climate change, may impact foraging behaviour and thereby the size-structure and dynamics of host–parasitoid indirect interaction networks.  相似文献   

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