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51.
An experiment was conducted in order to evaluate the effects of gestational undernutrition of rabbit does on growth, carcass composition and meat quality of the offsprings. Thirty primiparous non lactating rabbit does were artificially inseminated and randomly divided in three treatment groups: Control (C; fed to 100% of maintenance requirements throughout gestation, n = 10), early undernourished (EU; fed to 50% of maintenance requirements during days 7–19 of gestation, n = 10) and late undernourished (LU; fed to 50% of maintenance requirements during days 20-27 of gestation, n = 10). During the 4th week of the gestation period, LU does significantly lost weight compared to C and EU groups (P<0.05). At kindling, C does produced litters with higher proportions of stillborn kits (P<0.05) while the total litter size (alive and stillborn kits) was not different among groups (10.7, 12.8 and 12.7 kits in C, EU and LU groups, respectively). Kit birth weight tended to be lower in the LU group. During fattening, body weight and feed intake were not different among offsprings of the three experimental groups. Moreover, the maternal undernutrition did not have any impact on carcass composition of the offsprings in terms of carcass parts and internal organs weights as well as meat quality of L. lumborum muscle (pH24, colour, water holding capacity and shear values) at slaughter (70 days of age). Therefore, it can be concluded that the gestational undernutrition of the mother does not have detrimental effects on the productive and quality traits of the offsprings.  相似文献   
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The development of Tissue Engineered Vessels (TEVs) is advanced by the ability to routinely and effectively implant TEVs (4-5 mm in diameter) into a large animal model. A step by-step protocol for inter-positional placement of the TEV and real-time digital assessment of the TEV and native carotid arteries is described here. In vivo monitoring is made possible by the implantation of flow probes, catheters and ultrasonic crystals (capable of recording dynamic diameter changes of implanted TEVs and native carotid arteries) at the time of surgery. Once implanted, researchers can calculate arterial blood flow patterns, invasive blood pressure and artery diameter yielding parameters such as pulse wave velocity, augmentation index, pulse pressures and compliance. Data acquisition is accomplished using a single computer program for analysis throughout the duration of the experiment. Such invaluable data provides insight into TEV matrix remodeling, its resemblance to native/sham controls and overall TEV performance in vivo.  相似文献   
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The use of ROC curves in evaluating a continuous or ordinal biomarker for the discrimination of two populations is commonplace. However, in many settings, marker measurements above or below a certain value cannot be obtained. In this paper, we study the construction of a smooth ROC curve (or surface in the case of three populations) when there is a lower or upper limit of detection. We propose the use of spline models that incorporate monotonicity constraints for the cumulative hazard function of the marker distribution. The proposed technique is computationally stable and simulation results showed a satisfactory performance. Other observed covariates can be also accommodated by this spline‐based approach.  相似文献   
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Current clinical protocols used for isolation and purification of mesenchymal stem cells (MSC) are based on long-term cultures starting with bone marrow (BM) mononuclear cells. Using a commercially available immunoselection kit for enrichment of MSC, we investigated whether culture of enriched BM-CD105+ cells could provide an adequate number of pure MSC in a short time for clinical use in the context of graft versus host disease and graft failure/rejection. We isolated a mean of 5.4 × 105 ± 0.9 × 105 CD105+ cells from 10 small volume (10–25 ml) BM samples achieving an enrichment >100-fold in MSC. Seeding 2 × 103 immunoselected cells/cm2 we were able to produce 2.5 × 108 ± 0.7 × 108 MSC from cultures with autologous serum enriched medium within 3 weeks. Neither haematopoietic nor endothelial cells were detectable even in the primary culture cell product. Expanded cells fulfilled both phenotypic and functional current criteria for MSC; they were CD29+, CD90+, CD73+, CD105+, CD45; they suppressed allogeneic T-cell reaction in mixed lymphocyte cultures and retained in vitro differentiation potential. Moreover, comparative genomic hybridization analysis revealed chromosomal stability of the cultured MSC. Our data indicate that adequate numbers of pure MSC suitable for clinical applications can be generated within a short time using enriched BM-CD105+ cells.  相似文献   
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The extensive human-mediated modifications of shallow coastal habitats drastically alter selection regimes and may assist alien invasions. The preferential presence of a non-indigenous scleractinian coral (Oculina patagonica) on anthropogenic hard substrata was investigated in a highly disturbed coastal area, along the eastern Saronikos Gulf (Aegean Sea, Eastern Mediterranean). Although the species occurred on both natural and anthropogenic substrata at similar frequencies, its abundance was substantially higher on the latter. The species was present all along the shallow (0.5–5 m) infralittoral zone of the studied coastline, and its percent cover even exceeded 50 % at a site of anthropogenic hard substratum. The occupancy of the species declined with distance from a highly disturbed industrialized/urbanized area (Athens metropolitan coastal front and the port of Piraeus). Space availability as a result of habitat modification appears to have been an important factor enhancing the coral’s abundance in this area. The ongoing degradation of the coastal zone, as a combined effect of coastal pollution, proliferation of artificial substrata and overgrazing seems to be paving the way to this new invasion in the Aegean Sea.  相似文献   
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PurposeTo provide a guideline curriculum covering theoretical and practical aspects of education and training for Medical Physicists in Nuclear Medicine within Europe.Material and methodsNational training programmes of Medical Physics, Radiation Physics and Nuclear Medicine physics from a range of European countries and from North America were reviewed and elements of best practice identified. An independent panel of experts was used to achieve consensus regarding the content of the curriculum.ResultsGuidelines have been developed for the specialist theoretical knowledge and practical experience required to practice as a Medical Physicist in Nuclear Medicine in Europe. It is assumed that the precondition for the beginning of the training is a good initial degree in Medical Physics at master level (or equivalent). The Learning Outcomes are categorised using the Knowledge, Skill and Competence approach along the lines recommended by the European Qualifications Framework. The minimum level expected in each topic in the theoretical knowledge and practical experience sections is intended to bring trainees up to the requirements expected of a Medical Physicist entering the field of Nuclear Medicine.ConclusionsThis new joint EANM/EFOMP European guideline curriculum is a further step to harmonise specialist training of Medical Physicists in Nuclear Medicine within Europe. It provides a common framework for national Medical Physics societies to develop or benchmark their own curricula. The responsibility for the implementation and accreditation of these standards and guidelines resides within national training and regulatory bodies.  相似文献   
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