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排序方式: 共有159条查询结果,搜索用时 234 毫秒
81.
Barros L Venturini BA Baptista P Estevinho LM Ferreira IC 《Journal of agricultural and food chemistry》2008,56(10):3856-3862
The chemical composition and biological properties of Portuguese wild mushrooms ( Cantharellus cibarius, Hypholoma fasciculare, Lepista nuda, Lycoperdon molle, Lycoperdon perlatum, Ramaria botrytis, Tricholoma acerbum) were evaluated in order to assess these products as sources of nutrients and nutraceuticals. The analyzed mushrooms contain very useful phytochemicals such as phenolics, tocopherols, ascorbic acid, and carotenoids. All of the species proved to have antioxidant activity (measured by four different methods), being more significant for R. botrytis (EC 50 values < 1 mg/mL). Lycoperdon species were resistant to all of the tested microorganisms, and the other samples revealed antimicrobial activity selectively against Gram-positive bacteria, with very low minimal inhibitory concentration, in some cases, even lower than the standard. The combination of bioactive compounds and rich nutritional composition (high contents in protein and carbohydrates, low content in fat with the precious contribution of unsaturated fatty acids and the absence of trans fatty acids) in the mushroom makes it a very special food. 相似文献
82.
曾宪玮 ZENG XIAN WEI 彭德忠 PENG DE ZHONG 邹文生 ZOU WEN SHENG 彭洁贤 PENG JIE XIAN 陈祥发 CHEN XIANG FA 陈琨 CHEN KUN 《江西林业科技》2001,(6):23-25
通过对宜丰县云峰尖林场毛竹示范林的经营状况进行调查,分析了其经济效益、社会效益、生态效益。 相似文献
83.
Erika M. Nakazono Emilio M. Bruna Rita C. G. Mesquita 《Forest Ecology and Management》2004,190(2-3):219-225
The harvesting of non-timber forest products has been proposed as an alternative to timber harvesting that can increase rural income while having a reduced impact on forest structure. However, surprisingly little is known about the biological consequences of harvesting these products. We conducted a 3-year experiment in which we simulated the stem harvesting of the Amazonian plant Ischnosiphon polyphyllus, which is used by traditional and indigenous populations in the Amazon for the construction of baskets, mats, and other handicrafts used in manioc cultivation. We found that plant mortality is limited in all except the most extreme harvesting treatments. However, we also found that plants recuperate extremely slowly from experimental harvesting. These results suggest that current harvesting strategies may not be conservative enough to ensure long-term population survival. 相似文献
84.
Rebeca Scalco DVM Monica Aleman MVZ Cert PhD DACVIM Carlos E. W. Nogueira DVM MSc PhD Natalia B. Freitas DVM Bruna R. Curcio DVM MSc PhD 《Journal of Veterinary Emergency and Critical Care》2023,33(2):217-222
Objectives
To report red cell distribution width (RDW) values, to calculate RDW-to-platelet ratio (RPR), and to investigate a possible correlation of RDW and RPR index values in neonatal foals classified as healthy or at risk based on clinical information from a population of foals up to 24 hours of life.Design
Retrospective study conducted from records and CBCs of foals born between June and November from 2018 to 2020 foaling seasons.Setting
Breeding farm.Animals
Three hundred and nine neonatal full-term Thoroughbred foals.Interventions
None.Measurements and Main Results
Foals were evaluated by a veterinarian within 15 minutes after birth, and a blood sample was collected within 24 hours of life. Based on clinical information, 88 of 309 foals (28.4%) were considered at risk of perinatal disease, and 201 were healthy. Mean gestational age for the foals was 346.3 ± 9.7 days. RDW values did not differ between groups. Gestational length demonstrated to have a negative correlation with RDW (r = –0.156, P = 0.005) and mean corpuscular volume (r = –0.135, P = 0.01), indicating a link of these variables to foal maturity. RPR index was higher for at-risk (0.073 ± 0.018) than for healthy foals (0.068 ± 0.014, P = 0.01).Conclusion
RPR might be a promising early indicator of disease for the field triage of neonatal foals. 相似文献85.
86.
Alane P. O. Monte Jamile M. Santos Vanúzia G. Menezes Bruna B. Gouveia Thae L. B. G. Lins Ricssio S. Barberino Joozito L. Oliveira Nathalie J. Donfack Maria Helena T. Matos 《Reproduction in domestic animals》2019,54(9):1169-1176
This study analysed the effect of growth differentiation factor‐9 (GDF‐9) on the in vitro culture of isolated ovine secondary follicles. The follicles were cultured in α‐MEM supplemented with BSA, insulin, glutamine, hypoxanthine, transferrin, selenium, ascorbic acid and FSH (α‐MEM+—control medium) or α‐MEM+ supplemented with 1, 10, 50 or 100 ng/ml GDF‐9. Next, the oocytes were destined to in vitro maturation (IVM). After 12 days of culture, there were no differences regarding the percentage of normal follicles, antrum formation and follicle diameter between the treatments (p > 0.05). The rates of fully grown oocytes (≥110 µm) were higher (p < 0.05) in 100 ng/ml GDF‐9 than other treatments, except for 10 ng/ml of GDF‐9 (p > 0.05). Treatment containing 100 ng/ml GDF‐9 showed higher (p < 0.05) mitochondrial activity than the control group. Moreover, 100 ng/ml GDF‐9 showed more oocytes in MI than α‐MEM+, 1 or 50 ng/ml GDF‐9 (p < 0.05). In conclusion, 100 ng/ml GDF‐9 increased the growth, mitochondrial function and meiotic resumption of oocytes from in vitro grown sheep secondary follicles. 相似文献
87.
The genus Psidium includes important fruit crops. However, there are very few studies focusing on its reproductive biology, which limits the establishment of breeding programs. The present work investigated the reproductive biology of Psidium guajava and Psidium cattleianum in terms of compatibility of crossings between these two species aiming at interspecific hybridization because the latter species is an important source of resistance against the nematode Meloidogyne enterolobii. Several types of crosses were performed to understand the reproductive biology of these species, including the compatibility of intra- and interspecific crossings, using assisted in vivo germination of pollen grains on the stigma. In addition, the in vitro germination of both Psidium species was studied at different stages of fruit development to rescue young seeds to improve the chances of obtaining the hybrids. No fruits of 270 pollinations were obtained on guava buds at the pre-anthesis stage, regardless of the source of the pollen grain and the cultivar used as female genotype. Microscopic analyzes demonstrated the germination of pollen grains and pollen tube growth at crosses between guava cv. ‘Pedro Sato’ (P. guajava) and Psidium cattleianum. High germination percentages of Psidium cattleianum seeds were obtained in MS medium without sucrose or containing 15 g/L of this carbohydrate. 相似文献
88.
89.
Global mitochondrial DNA (mtDNA) methylation has been recently described in bovine and showed particular signatures in both gametes and embryos. Here, we investigated the distribution of mtDNA methylation through strand-specific mapping of methylation sites to gain perspective on how epigenetic mechanisms can be involved in mitochondrial function. We demonstrate that in both oocytes and embryos, the frequency of methylation is biased towards the light strand (L-strand), particularly in the gene bodies and in the region containing the L-strand promoter (LSP). Methylation is not restricted to CpG nucleotides and is not symmetrical on both strands. This configuration reinforces the hypothesis of a specific epigenetic regulation of mtDNA, which is an important observation for the understanding of how mitochondrial function is regulated. 相似文献
90.
Comparison of equine bone marrow-, umbilical cord matrix and amniotic fluid-derived progenitor cells
Lovati AB Corradetti B Lange Consiglio A Recordati C Bonacina E Bizzaro D Cremonesi F 《Veterinary research communications》2011,35(2):103-121
The aim of the study was to compare in vitro the stemness features of horse progenitor cells derived from bone marrow (BM-MSCs),
amniotic fluid (AF-MSCs) and umbilical cord matrix (EUC-MSCs). It has been suggested that there may be a stem cell population
within both umbilical cord matrix and amniotic fluid. However, little knowledge exists about the characteristics of these
progenitor cells within these sources in the equine species. This study wanted to investigate an alternative and non-invasive
stem cell source for the equine tissue engineering and to learn more about the properties of these cells for future cell banking.
Bone marrow, umbilical cord and amniotic fluid samples were harvested from different horses. Cells were analyzed for proliferation,
immunocytochemical, stem cell gene expression and multilineage plasticity. BM- and AF-MSCs took similar time to reach confluence
and showed comparable plating efficiency. All cell lines expressed identical stem cell markers and capability to differentiate
towards osteogenic lineage. Almost all cell lines differentiated into the adipogenic lineage as demonstrated by cytochemical
staining, even if no adipose gene expression was detectable for AF-MSCs. AF- and EUC-MSCs showed a limited chondrogenic differentiation
compared with BM-MSCs as demonstrated by histological and biochemical analyses. These findings suggest that AF-MSCs appeared
to be a readily obtainable and highly proliferative cell line from an uninvasive source that may represent a good model system
for stem cell biology. More studies are needed to investigate their multilineage potential. EUC-MSCs need to be further investigated
regarding their particular behavior in vitro represented by spheroid formation. 相似文献