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561.
The aim of the study was to evaluate the effect of a temporary quantitative feed restriction on growth performance, nutrient digestibility and carcass criteria of rabbits. A total of 80 weaned male Californian rabbits (30 d of age) were randomly assigned to four treatments of 20 rabbits each. The Control group was fed ad libitum during the whole experimental period (days 30–72 of age). For the three restricted fed groups the feed intake was reduced by 15%, 30% and 45% compared to the Control group, respectively. The feed restriction was applied after weaning and lasted for 21 d. Thereafter, at 51 d of age, in all treatments the feed supply returned to ad libitum intake till 72 d of age (AL period). The feed restriction decreased the body weight gain of rabbits (during the restriction period and the whole experimental period, p < 0.001) and improved feed conversion ratio during all tested periods (p < 0.001). In the AL period, the daily body weight gain of all groups was similar. After the AL period, the digestibility of all measured nutrients was significantly higher for animals fed restrictively. Furthermore, feed restrictions significantly decreased the proportion of perirenal and scapular fat and increased relative weight and length of the gastrointestinal tract. Therefore, it can be concluded that the applied feed restriction improved feed conversion, nutrient digestibility and reduced fat at the slaughter age of Californian rabbits, but the reduced body weight gain could not be compensated by a subsequent ad libitum feeding for 3 weeks.  相似文献   
562.

Background

Previously, ethnic inequalities in prognosis after a first acute myocardial infarction were observed in the Netherlands. This might be due to differences in revascularisation rate between ethnic minority groups and ethnic Dutch. Therefore, we investigated inequalities in revascularisation rate after occurrence of an ST-elevation myocardial infarction (STEMI) between first generation ethnic minority groups (henceforth, migrants) and ethnic Dutch.

Methods

All STEMI events between 2006 and 2011 were identified in a subset of the Achmea Health Database, which records medical care to persons insured at the Achmea health insurance company, a major health insurance company in the central part of the Netherlands. Ethnic Dutch and migrants from Suriname (Hindustani Surinamese and non-Hindustani Surinamese), Morocco, and Turkey were included (n = 1,765). Multivariable Cox proportional hazards regression analyses were used to identify ethnic inequalities in revascularisation rate (percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG)) after a STEMI event.

Results

On average, 73.2% of STEMI events were followed by a revascularisation procedure. After adjustment for confounders (age, sex, degree of urbanization) no significant differences in revascularisation rate were found between the ethnic Dutch population and Hindustani Surinamese (HR: 1.04; 0.85–1.27), non-Hindustani Surinamese (HR: 0.98; 0.63–1.51), Moroccan (HR: 0.94; 0.77–1.14), and Turkish migrants (HR: 1.04; 0.88–1.24). Additional adjustment for comorbidity and neighborhood income did not change our findings.

Conclusion

Our study suggests no ethnic inequalities in revascularisation rate after a STEMI event. This finding is in agreement with the universally accessible health care system in the Netherlands.  相似文献   
563.

Background

Retention to HIV care is vital for patients’ survival, to prevent onward transmission and emergence of drug resistance. Travelling to receive care might influence adherence. Data on the functioning of and retention to HIV care in the Central African region are limited.

Methods

This retrospective study reports outcomes and factors associated with retention to HIV care at a primary HIV clinic in Lambaréné, Gabon. Adult patients who presented to this clinic between January 2010 and January 2012 were included. Outcomes were retention in care (defined as documented show-up for clinical visits, regardless of delay) or LTFU (defined as a patient not retained in care; on ART or ART naïve, not returning to care during the study period with a patient delay for scheduled visits of more than 6 months), and mortality. Cox regression analysis was used to assess factors associated with respective outcomes. Qualitative data on reasons for LTFU were obtained from focus-group discussions.

Results

Of 223 patients included, 67.3% were female. The mean age was 40.5 (standard deviation 11.4) years and the median CD4 count 275 (interquartile range 100.5–449.5) cells/μL. In total, 34.1% were lost to follow up and 8.1% died. Documented tuberculosis was associated with increased risk of being LTFU (adjusted hazard ratio (aHR) 1.80, 95% confidence interval (95% CI) 1.05–3.11, P = 0.03), whereas early starting anti-retroviral therapy (ART) was associated with a decreased risk of LTFU (aHR 0.43, 95%CI 0.24–0.76, P = 0.004), as was confirmed by qualitative data.

Conclusions

Retention to HIV care in a primary clinic in Gabon is relatively poor and interventions to address this should be prioritized in the HIV program. Early initiation of ART might improve retention in care.  相似文献   
564.
Gold nanoparticle mediated (GNOME) laser transfection is a powerful technique to deliver small biologically relevant molecules into cells. However, the transfection of larger and especially negatively charged DNA remains challenging. The efficiency for pDNA was 0.57% using parameter that does not influence the endo‐ and exogenous DNA. In order to gain a deeper understanding of the actual molecule uptake process, the uptake efficiency was determined using molecules of different sizes. It was evaluated that uncharged dextran molecules (2000 kDa) were delivered with an efficiency of 68%. The intracellular distribution of injected molecules was visualized and larger molecules were primary found in the cytoplasm. Patch clamp measurements suggested a permeabilization time up to 15 minutes. The uptake efficiency depended on the size and charge of the molecule to deliver as well as the cell size. A minor role for transfection plays the cell type since primary stem cells were successfully transfected.

The perforation efficiency of semi‐adherent and suspension cells is influenced by the cell and molecule size.  相似文献   

565.
This study investigates the cellular response of murine hepatoma cells to the polycyclic aromatic hydrocarbon benzo[a]pyrene (B[a]P) using two‐photon and confocal laser scanning microscopy. The intracellular distribution of B[a]P and the B[a]P/AhR complex was visualized time‐ and concentration‐dependent for up to 48 h of exposure. B[a]P was predominantly found in lipid droplets, endoplasmic reticulum and lysosomes, where B[a]P is collected and forms large aggregates. Changes in mitochondrial membrane potential and bleb formation due to high B[a]P concentrations were observed. The imaging data presented in this study provide new insights into the systemic cellular regulation following B[a]P exposure. (© 2014 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)  相似文献   
566.
Kin selection theory predicts that cooperation is facilitated between genetic relatives, as by cooperating with kin an individual might increase its inclusive fitness. Although numerous theoretical papers support Hamilton's inclusive fitness theory, experimental evidence is still underrepresented, in particular in noncooperative breeders. Cooperative predator inspection is one of the most intriguing antipredator strategies, as it implies high costs on inspectors. During an inspection event, one or more individuals leave the safety of a group and approach a potential predator to gather information about the current predation risk. We investigated the effect of genetic relatedness on cooperative predator inspection in juveniles of the cichlid fish Pelvicachromis taeniatus, a species in which juveniles live in shoals under natural conditions. We show that relatedness significantly influenced predator inspection behaviour with kin dyads being significantly more cooperative. Thus, our results indicate a higher disposition for cooperative antipredator behaviour among kin as predicted by kin selection theory.  相似文献   
567.
568.
Woolly apple aphid (WAA, Eriosoma lanigerum Hausmann) (Hemiptera: Aphididae) is a major pest of apple trees (Malus domestica, order Rosales) and is critical to the economics of the apple industry in most parts of the world. Here, we generated a chromosome‐level genome assembly of WAA—representing the first genome sequence from the aphid subfamily Eriosomatinae—using a combination of 10X Genomics linked‐reads and in vivo Hi‐C data. The final genome assembly is 327 Mb, with 91% of the assembled sequences anchored into six chromosomes. The contig and scaffold N50 values are 158 kb and 71 Mb, respectively, and we predicted a total of 28,186 protein‐coding genes. The assembly is highly complete, including 97% of conserved arthropod single‐copy orthologues based on Benchmarking Universal Single‐Copy Orthologs (busco ) analysis. Phylogenomic analysis of WAA and nine previously published aphid genomes, spanning four aphid tribes and three subfamilies, reveals that the tribe Eriosomatini (represented by WAA) is recovered as a sister group to Aphidini + Macrosiphini (subfamily Aphidinae). We identified syntenic blocks of genes between our WAA assembly and the genomes of other aphid species and find that two WAA chromosomes (El5 and El6) map to the conserved Macrosiphini and Aphidini X chromosome. Our high‐quality WAA genome assembly and annotation provides a valuable resource for research in a broad range of areas such as comparative and population genomics, insect–plant interactions and pest resistance management.  相似文献   
569.
Plants experience a decrease in the red:far-red light ratio (R:FR) when grown at high planting density. In addition to eliciting the shade avoidance response, low R:FR also enhances plant susceptibility to pathogens via modulation of defense hormone-mediated responses. However, other mechanisms, also affected by low R:FR, have not been considered as potential components in FR-induced susceptibility. Here, we identify FR-induced accumulation of leaf soluble sugars as a novel component of FR-induced susceptibility. We observed that phytochrome inactivation by FR or phytochrome B mutation was associated with elevated leaf glucose and fructose levels and enhanced disease severity caused by Botrytis cinerea. By experimentally manipulating internal leaf sugar levels, we found that the FR-induced susceptibility in tomato was partly sugar-dependent. Further analysis revealed that the observed sugar accumulation in supplemental FR occurred in a jasmonic acid (JA)-dependent manner, and the JA biosynthesis mutant def1 also displayed elevated soluble sugar levels, which was rescued by exogenous methyl jasmonate (MeJA) application. We propose that the reduced JA responsiveness under low R:FR promotes disease symptoms not only via dampened induction of defense responses, but also via increased levels of soluble sugars that supports pathogen growth in tomato leaves.  相似文献   
570.
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