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1.
The effects of different fatty acid (FA) contents in diet on serum parameters, FA compositions of eggs and meat, and liver morphological changes were studied in Shaoxing laying ducks. A total of 264 ducks at 17 weeks were fed a control diet or a diet containing 30 g/kg fish oil (FO), 25 g/kg sunflower oil (SO), or 30 g/kg palm oil with 20 g/kg beef tallow (PBO). Malondialdehyde (MDA) content in the liver and the serum of ducks fed the PBO diet was significantly (P<0.05) higher than that of ducks fed the other diets. Triglyceride (TG) and total cholesterol (TC) levels were significantly lower (P<0.05) in ducks fed the FO diet. Serum TC also was lower in ducks fed the SO diet. Superoxide dismutase (SOD) activity was also affected by diets. The contents of polyunsaturated FAs (PUFAs) in eggs and meat were significantly higher (P<0.001) in ducks fed the FO and SO diets than in ducks fed the control diet. The level of C22:6 (n-3) FA in ducks fed the FO diet was significantly higher than that in ducks fed the other diets. However, the conversion efficiency of the longer-chain C20:5 (n-3) FA was higher than that of C22:6 (n-3). Ducks fed the PBO diet exhibited lipid droplet accumulation in the liver. These results demonstrate that a diet enriched with different FAs has strong effects on serum lipid levels and the deposition of PUFAs into tissue lipids.  相似文献   

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3.
Formative Assessment (FA) refers to eliciting evidence about students’ understanding and using the information to support learning, e.?g. via individual feedback. There is evidence that FA fosters students’ motivation, but less is known about the underlying processes. The present study investigates direct effects of FA on intrinsic motivation as well as the mediating role of students’ perceived competence, drawing on Deci and Ryan’s self-determination theory. In a randomized, controlled trial, primary school teachers were either assigned to an FA training (n?=?17) or to a control group (CG; n?=?11). All teachers then taught two science units in their classrooms (FA: n?=?319 students, CG: n?=?232). Multilevel regression analyses showed a higher perceived competence and a marginally higher intrinsic motivation for FA students after unit 1. After unit 2, both intrinsic motivation and perceived competence were higher in the FA condition, and the impact on intrinsic motivation was significantly mediated by students’ perceived competence after the first unit. These results confirm and extend previous findings on the effectiveness of formative assessment on motivational outcomes.  相似文献   

4.
To investigate the effects of hypoxic exercise training on microRNA (miRNA) expression and the role of miRNA expression in regulating lipid metabolism, 20 dietary-induced obese SD rats were divided into a normoxic sedentary group (N, n=10) and a hypoxic exercise training group (H, n=10). After four weeks, measurements were taken of body weight, body length, fat mass, serum lipid concentration, miRNAs differentially expressed in rat liver, and gene and protein expression levels of peroxisome proliferator activated receptor α (PPARα), fatty acid synthetase (FAS), and carnitine palmitoyl transferase 1A (CPT1A) in rat liver. Body weight, Lee’s index, fat mass, fat/weight ratio, and serum levels of total cholesterol (TC) and high density lipoprotein cholesterol (HDL-C) were all significantly lower in the H group than in the N group (P<0.01). Six miRNAs expressed significantly differently in the liver (P<0.05). Specifically, expression levels of miR-378b were significantly lower in the H group than in the N group (P<0.05). Compared with the normoxic sedentary group, hypoxic exercise training resulted in a lower ratio of FAS mRNA to CPT1A mRNA (P<0.05), as well as lower CPT1A protein levels (P<0.01), while a higher ratio of FAS to CPT1A protein levels (P<0.01) was observed. In conclusion, hypoxic training may elevate the resistance of high fat diet induced obesity in rats by reducing the expression of miR-378b, and decrease the fatty acid mitochondrial oxidation in obese rat livers by decreasing the protein expression of CPT1A and increasing the protein expression ratio of FAS/CPT1A.  相似文献   

5.

Objective

Being overweight or obese comprises a significant risk factor for atherosclerosis. Fat tissue also generates factors stimulating angiogenesis, the process by which new blood vessels form. The purpose of this paper is to assess concentrations of the vascular endothelial growth factor A (VEGF-A) and its soluble type-1 and type-2 receptors (sVEGFR-1 and sVEGFR-2) in plasma of patients with peripheral arterial disease (PAD) depending on the level of nutrition according to body mass index (BMI).

Methods

The study group included patients suffering from symptomatic PAD (n=46) in Fontaine classes IIa–IV without any history of neoplastic disease and who have a normal BMI (n=15), are overweight (n=21) or are obese (n=10). The control group (n=30) consisted of healthy non-smoking volunteers who were neither overweight nor obese. Venous blood plasma samples were collected from both groups at rest in the morning to determine plasma concentrations of VEGF-A, sVEGFR-1, and sVEGFR-2 using the enzymelinked immunosorbent assay (ELISA) method.

Results

The group of patients with PAD co-existent with being overweight or obese tended to have higher mean concentration levels of VEGF-A and sVEGFR-2 when compared with patients suffering from PAD with normal BMI. A statistically significant positive correlation was obtained between BMI and average plasma concentrations of sVEGFR-2 (R=0.37, P=0.0103). However, no significant correlation was noticed between BMI and VEGF-A or sVEGFR-1 concentrations.

Conclusions

A positive correlation determined between the level of antiangiogenic factor and BMI value may be indicative of the linearly growing prevalence of some antiangiogenic factors in patients with metabolic disorders, which may be one of numerous factors contributing to incomplete efficiency of collateral circulation development in patients with PAD.
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6.
Social media (SM) support new approaches to learning that rely on voluntary, peer-to-peer communication using devices and software provided and managed by students rather than on institutional course management systems. We present one case of such an approach with first-year university students (n = 86) in Thailand using SM for asking and answering questions between peers in a face-to-face computer-programming course. Encouraging students to ask questions about course content can result in improved performance. In general, understanding how students participate and what drives them to participate can provide insights into how universities and instructors can be socially ready. Students used SM during 10 weeks of an 18-week course. Each of four sections selected one form of SM as follows: Facebook [n = 33], Instagram [n = 21], Twitter [n = 21], and Line [n = 11]. The mixed-methods case study involved quantitative measures of how students participated and quantitative and qualitative measures of students’ perceptions of what drives or discourages their participation. Results revealed patterns in participation as follows: participation and motivation; passive and active participation; participation and sample size; participation and type of SM and; participation and student demographics. Implications for practice relate to the value of instructors’ understanding of the social incentives for student participation such as social recognition, gratification of needs and convenience. Implications for research focus on the value of investigating new forms of participation available to read-only participants and ‘lurkers’ using features of SM such as ‘liking’ and sharing.  相似文献   

7.
The study investigates the preschool readiness of moderately preterm children and, in particular, the likely presence of learning disabilities at preschool age. Its theoretical model detects linguistic comprehension and expression; memory-related metacognition and cognition skills; orientation and motor coordination skills; premathematics and preliteracy ones. The research project involved an experimental group made up of 55 moderately preterm children (mean age?=?62 months, mean gestational age?=?34.6 weeks), without any clinical neonatal complications, and low birth weight (M?=?2,100 g, SD?=?350 g); a control group made up of 55 full-term children without pre- and perinatal complications. The children’s primary school reference teachers were given a questionnaire (Observative Questionnaire for Early Identification of Learning Disabilities), which was aimed at identifying any likely social and cognitive skill deficits at preschool age. The data, submitted to nonparametric univariate variance, show how scores of moderately preterm children in the metacognition [U (n1 e?n2?=?55)?=?35, p?=?0.04, r?=?0.49] are statistically lower, other cognitive skills (memory, orientation, and visual–motor coordination) [U (n1?e?n2?=?55)?=?32, p?=?0.02, r?=?0.45], premathematics [U (n1?e?n2?=?55)?=?32, p?=?0.02, r?=?0.44], and the total score [U (n1?e?n2?=?55)?=?31, p?=?0.02, r?=?0.12]. Such data would seem to suggest the need for hypothesizing preventive training and educational paths as a prerequisite for the development of the school abilities.  相似文献   

8.
In the province of Ontario (Canada), over 28,900 adolescents are investigated by child welfare agencies each year because of suspected maltreatment. Exposure to childhood maltreatment represents a major threat to the psychological well-being of young people, particularly in terms of trauma-related stress. The present study investigated trauma symptom profiles among 479 adolescents (13–17 years) involved with the Canadian child welfare system between 2003 and 2010. Latent profile analysis identified three profiles using self-report data from the Trauma Symptom Checklist for Children. Most adolescents (59%, n = 281) were classified into the profile depicting minimal trauma-related symptoms, 30% (n = 144) were characterized by moderate trauma-related symptoms, and 11% (n = 54) were in the profile reflecting severe trauma-related symptoms. Several variables predicted profile membership. Greater severity of sexual abuse and female sex were associated with a greater likelihood of belonging to the severe trauma symptom profile than both the moderate and the minimal trauma symptom profiles. In addition, having society ward status (compared to crown ward) was related to an increased likelihood of belonging to both the severe and moderate symptom profiles relative to the minimal symptom profile. This study provides some insight into the typologies of trauma experienced among child-welfare-involved adolescents and the set of factors which relate to the specific profiles. Findings are important for informing psychological assessment practices, as well as tailored interventions, for adolescents in the child welfare system.  相似文献   

9.

Background and objective

Rivaroxaban is a new oral anticoagulant for stroke prevention in patients with non-valvular atrial fibrillation (NVAF), which has less drug–food interaction than warfarin. We conducted this prospective randomized study to evaluate the metabolic benefits as well as the safety and efficacy with rivaroxaban versus warfarin in patients with NVAF following radiofrequency catheter ablation (RFCA).

Methods

From April to July 2014, 60 patients with NVAF undergoing RFCA were prospectively enrolled in our study. Following RFCA, all patients were randomly assigned to receive rivaroxaban (Group R, n=30) or warfarin (Group W, n=30). Metabolic indices including serum total protein, albumin, globulin, and high-density lipoprotein (HDL) as well as bleeding, stroke, and systemic thromboembolism events were evaluated and compared during follow-up after 15, 30, 60, and 90 d of RFCA procedure.

Results

Serum total protein, albumin, globulin, and HDL levels were all significantly elevated at each follow-up stage in Group R when compared to the baseline (P<0.05 respectively). In Group W, the metabolic indices decreased at first and then had an increasing trend. There were no deaths or thromboembolic complications in each group. The prevalence of total bleeding complications was similar between Group R and Group W (11/30, 36.7% vs. 10/30, 33.3%, P=0.79).

Conclusions

Patients with NVAF receiving rivaroxaban after RFCA procedures appear to benefit from a metabolic perspective compared with warfarin, providing practical clinical reference for the choice of the anticoagulant. Rivaroxaban seems to be as safe and effective in preventing thromboembolic events as warfarin for these patients.
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10.
(R)-2-hydroxy-3-phenylpropionic acid (PLA) is an ideal antimicrobial compound with broad-spectrum activity against a wide range of Gram-positive bacteria, some Gram-negative bacteria, and fungi. We studied the bioconversion of phenylpyruvate (PPA) to PLA using whole recombinant Escherichia coli cells in a series of buffer/organic solvent systems. Octane was found to be the best organic solvent. The optimum volume ratio of the water phase to the n-octane phase, conversion temperature, substrate concentration, and cell concentration were 6:4, 40 °C, 12.5 g/L, and 30 g/L wet cells, respectively. Under the optimized conditions, the average PLA productivity in the aqueous/n-octane system was 30.69% higher than that in the aqueous system, and 32.31 g/L PLA was obtained with the use of a stirred reactor (2-L scale). Taken together, our findings indicated that PLA biosynthesis was more efficient in an aqueous/n-octane biphasic system than in a monophasic aqueous system. The proposed biphasic system is an effective strategy for enhancing PLA yield and the biosynthesis of its analogues.  相似文献   

11.
Because of their physiological similarity to humans, pigs provide an excellent model for the study of obesity. This study evaluated diet-induced adiposity in genetically lean pigs and found that body weight and energy intake did not differ between controls and pigs fed the high-fat (HF) diet for three months. However, fat mass percentage, adipocyte size, concentrations of total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C), insulin, and leptin in plasma were significantly higher in HF pigs than in controls. The HF diet increased the expression in backfat tissue of genes responsible for cholesterol synthesis such as Insig-1 and Insig-2. Lipid metabolism-related genes including sterol regulatory element binding protein 1c (SREBP-1c), fatty acid synthase 1 (FASN1), diacylglycerol O-acyltransferase 2 (DGAT2), and fatty acid binding protein 4 (FABP4) were significantly up-regulated in backfat tissue, while the expression of proliferator-activated receptor-α (PPAR-α) and carnitine palmitoyl transferase 2 (CPT2), both involved in fatty acid oxidation, was reduced. In liver tissue, HF feeding significantly elevated the expression of SREBP-1c, FASN1, DGAT2, and hepatocyte nuclear factor-4α (HNF-4α) mRNAs. Microarray analysis further showed that the HF diet had a significant effect on the expression of 576 genes. Among these, 108 genes were related to 21 pathways, with 20 genes involved in adiposity deposition and 26 related to immune response. Our results suggest that an HF diet can induce genetically lean pigs into obesity with body fat mass expansion and adipose-related inflammation.  相似文献   

12.
It had been proved that administration of sevoflurane for the first two minutes of reperfusion effectively protects the heart against reperfusion injury in rats in vivo.Our aim was to investigate the duration of effective sevoflurane administration and its underlying mechanism in isolated rat hearts exposed to global ischemia/reperfusion(I/R) injury.Adult male Sprague-Dawley rats were randomly divided into six groups(n=12):a sham-operation group,an I/R group,and four sevoflurane postconditioning groups(S2,S5,S10,and S15).In the S2,S5,S10,and S15 groups,the duration times of sevoflurane administration were 2,5,10,and 15 min after the onset of reperfusion,respectively.The isolated rat hearts were mounted on the Langendorff system,and after a period of equilibrium were subjected to 40 min global ischemia and 120 min reperfusion.Left ventricular(LV) hemodynamic parameters were monitored throughout each experiment and the data at 30 min of equilibrium and 30,60,90,and 120 min of reperfusion were analyzed.Myocardial infarct size at the end of reperfusion(n=7 in each group) and the expression of myocardial phosphorylated Akt(p-Akt) after 15-min reperfusion were determined in a duplicate set of six groups of rat hearts(n=5 in each group).Compared with the I/R group,the S5,S10,and S15 groups had significantly improved left ventricular end-diastolic pressure(LVEDP),left ventricular developed pressure(LVDP),and the maximal rate of rise or fall of the LV pressure(±dP/dtmax),and decreased myocardial infarct size(P<0.05),but not the S2 group.After 15 min of reperfusion,the expression of p-Akt was markedly up-regulated in the S5,S10,and S15 groups compared with that in the I/R group(P<0.05),but not in the S2 group.Sevoflurane postconditioning for 5 min was sufficient to activate Akt and exert maximal cardioprotection against I/R injury in isolated rat hearts.  相似文献   

13.
Objective: The intoxications caused by 2,4-dinitrophenol (2,4-DNP), even death, have been frequently reported in recent years. This study aims to investigate the dynamic changes of plasma toxin concentration and explore the clinical value of resin hemoperfusion (HP) in the treatment of patients with acute 2,4-DNP poisoning. Methods: We reported 16 cases of acute 2,4-DNP poisoning through occupational exposure due to ignoring the risk of poisoning. The blood samples were collected from the 14 survivors. According to the different treatments of resin HP, the survivors were divided into routine HP (n=5) and intensive HP (n=9) groups. Ultra high performance liquid chromatography/tandem mass spectroscopy (UPLC-MS/MS) was used to detect the 2,4-DNP concentration in plasma in this study. Results: The 14 survivors recovered very well after treatment. The initial plasma 2,4-DNP concentrations (C 1) of survivors ranged from 0.25 to 41.88 µg/ml (mean (12.56±13.93) µg/ml). A positive correlation existed between initial plasma 2,4-DNP concentration (C 1) and temperature. The elimination of 2,4-DNP was slow and persistent, and the total clearance rates of plasma toxin from the 1st to 3rd day (R 3), the 3rd to 7th day (R 3–7), and the 1st to 7th day (R 7), were only (53.03±14.04)%, (55.25±10.50)%, and (78.29±10.22)%, respectively. The plasma toxin was cleared up to 25 d after poisoning in most of the patients. The R 3, R 3–7, and R 7 in the intensive HP group were all apparently higher than those in the routine HP group, with statistical significance (P<0.05). Simultaneously, the elimination half-life (t 1/2) of 2,4-DNP in the intensive HP group was apparently shorter than that in the routine HP group, with statistical significance (P<0.05). Conclusions: The clinicians should be aware of this slow and persistent process in the elimination of plasma 2,4-DNP. Higher initial plasma toxin concentration resulted in a more severe fever for the patient. According to the limited data, longer and more frequent resin HP may accelerate to eliminate the poison.  相似文献   

14.
There is a substantial and persistent gap in achievement between children from different backgrounds [National Center for Education Statistics. (2002). Children's reading and mathematics achievement in kindergarten and first grade. Washington, DC: U.S. Government Printing Office] that can be traced to the preschool years [Snow, C. E., Burns, M. S., & Griffin, P. (Eds.). (1998). Preventing reading difficulties in young children. Washington, DC: National Research Council, National Academy Press], highlighting the importance of ensuring that preschools that serve low-income populations provide strong support for children's language and early literacy development. The current project sought to improve program quality in Head Start classrooms throughout New England with the Literacy Environment Enrichment Program (LEEP), an in-service intervention that was delivered in the form of a credit-bearing course. The impact of LEEP was studied using a wait-list comparison group strategy to determine whether intervention group teachers (n = 30) showed more fall–spring growth in measures of classroom support for literacy than did comparison group teachers (n = 40). Multiple hierarchical regression analyses that controlled for background measures and fall scores on classroom measures revealed moderate to large positive effects on all measures of classrooms support for language and early literacy with the exception of writing, for which only a small effect was found.  相似文献   

15.
Although the management of chronic heart failure (CHF) has made enormous progress over the past decades, CHF is still a tremendous medical and societal burden. Metabolic remodeling might play a crucial role in the pathophysiology of CHF. The characteristics and mechanisms of metabolic remodeling remained unclear, and the main hypothesis might include the changes in the availability of metabolic substrate and the decline of metabolic capability. In the early phases of the disease, metabolism shifts toward carbohydrate utilization from fatty acids (FAs) oxidation. Along with the progress of the disease, the increasing level of the hyperadrenergic state and insulin resistance cause the changes that shift back to a greater FA uptake and oxidation. In addition, a growing body of experimental and clinical evidence suggests that the improvement in the metabolic capability is likely to be more significant than the selection of the substrate.  相似文献   

16.
We investigated the fatty acid profiles of muscle from large yellow croaker (Pseudosciaena crocea R.) of different age. One- and two-year-old fish were cultured in floating net cages and sampled randomly for analysis. Moisture, protein, lipid and ash contents were determined by methods of Association of Analytical Chemist (AOAC) International. Fatty acid profile was determined by gas chromatography. Crude protein, fat, moisture and ash contents showed no significant differences between the two age groups. The contents of total polyunsaturated fatty acids and docosahexaenoic acid (DHA) were significantly higher and eicosapentaenoic acid (EPA) content was significantly lower in the two-year-old large yellow croaker than in the one-year-old (P<0.05). No significant differences were observed in the contents of total saturated fatty acids and monounsaturated fatty acids, or the ratio of n-3/n-6 fatty acids among the large yellow croakers of the two age groups. We conclude that large yellow croakers are good food sources of EPA and DHA.   相似文献   

17.
As an easy application of the intermediate value theorem, one can show that for any continuous function f: [0, 1] → ? with f (0) = f (1), there are points a, a + 1/2 both in [0, 1] such that f (a) = f (a + 1/2). In this note, we show that this property holds with 1/2 replaced by any number of the form 1/n for a positive integer n. More interestingly, we show that this is false for every number not of the form 1/n.  相似文献   

18.
This study examined preschool teachers’ (n = 59) explicit print instruction during shared reading and considered whether the benefits of this practice to children's learning (n = 379) varied as a function of the classroom environment and children's developmental characteristics. Measures of explicit print instruction and the classroom environment (global classroom quality, literacy environment) were obtained by aggregating observations taken across the 30 weeks of the study. Child outcomes were measured as spring print knowledge performance, controlling for fall. Child developmental characteristics were measured directly (language ability) and indirectly (attentional skills) in fall and winter, respectively. Findings showed that explicit print instruction contributed to children's learning, but its benefits decreased as the quality of the classroom and children's attentional skills increased. Implications for research and practice are discussed.  相似文献   

19.
In this study we aimed to analyze the effects of water temperature and diet on the length-weight relationship and condition of juvenile Malabar blood snapper Lutjanus malabaricus over a 30-d experimental period. The experiment was conducted in the laboratory using a flow-through-sea-water system. The fish were subjected to four different temperatures (22, 26, 30, and 34 °C) and two diets (commercial pellet and natural shrimp). Fish were fed twice daily. L. malabaricus exhibited negative allometric growth (b<3) at the beginning of the experiment (Day 0) at all temperatures and both diets except for 22 °C fed with shrimp, which showed isometric growth (b=3). Conversely, at the end of the experiment (Day 30) fish showed isometric growth (b=3) at 30 °C fed with the pellet diet, indicating that the shape of the fish did not change with increasing weight and length, and a positive allometric growth (b>3) at 30 °C fed with shrimp diet, which indicated that fish weight increases faster than their length. The rest of the temperatures represented negative allometric growth (b<3) on both diet, meaning that fish became lighter with increasing size. The condition factors in the initial and final measurements were greater than 1, indicating the state of health of the fish, except for those fed on a pellet diet at 34 °C. However, the best condition was obtained at 30 °C on both diets. Nevertheless, diets did not have a significant effect on growth and condition of juvenile L. malabaricus. The data obtained from this study suggested culturing L. malabaricus at 30 °C and feeding on the pellet or shrimp diet, which will optimize the overall production and condition of this commercially important fish species.  相似文献   

20.
Frontal asymmetry (FA), the difference in brain activity between the left versus right frontal areas, is thought to reflect approach versus avoidance motivation. This study (2012–2021) used functional near-infrared spectroscopy to investigate if infant (Mage = 7.63 months; N = 90; n = 48 male; n = 75 White) FA in the dorsolateral prefrontal cortex relates to psychopathology in later childhood (Mage = 62.05 months). Greater right FA to happy faces was associated with increased internalizing (η2 = .09) and externalizing (η2 = .06) problems at age 5 years. Greater right FA to both happy and fearful faces was associated with an increased likelihood of a lifetime anxiety diagnosis (R2 > .13). FA may be an informative and early-emerging marker for psychopathology.  相似文献   

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