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排序方式: 共有1310条查询结果,搜索用时 15 毫秒
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The aim of the study was to determine identification, three-dimensional modelling, and morphometry of intracranial arteries in New Zealand Rabbit by using computed tomography angiography. A total of 20 adult New Zealand Rabbits from both sexes were used in the study. General anaesthesia procedure was followed before computed tomography angiography imaging. Rabbits were placed in a prone position for imaging. Computed tomography angiography imaging was performed by injecting contrast agent into vena auricularis marginalis of rabbits. Morphometric measurements of the specified points were taken by MIMICS program using the computed tomography angiography images acquired. Three-dimensional intracranial artery model was prepared from the two-dimensional images on the same program. Measurements were statistically compared in terms of sex and side. It was observed in the study that arteria basilaris was generated by bilateral arteria vertebralis at the basal level of medulla oblongata. In the study, a statistically significant difference was determined only in diameter values of arteria cerebri caudalis dextra et sinistra in both female and male rabbits. On the other hand, no statistically significant difference was determined with respect to the side. Consequently, we think that the data of the present study will contribute to further studies on cerebrovascular pathology, clinicians or researchers. 相似文献
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2002—2015年,采用同步调查法对鄱阳湖区反嘴鹬(Recurvirostra avosetta)越冬种群数量动态与空间分布格局进行了监测。结果表明:鄱阳湖区分布有稳定的反嘴鹬越冬种群,年平均数量为(16684±14653)只,2004年、2005年、2013年种群数量均超过目前其全球数量的10%,2004年冬季鄱阳湖区越冬反嘴鹬数量达到最大值,为47520只。鄱阳湖区共有70个湖泊记录到反嘴鹬,其中反嘴鹬种群数量达到全球1%以上的湖泊有20个。每年冬季鄱阳湖区反嘴鹬集中分布在常湖、蚌湖、花庙湖和下坝湖,而反嘴鹬利用频次最高的是大湖池,每年反嘴鹬的越冬数量为(1819±1593)只。各湖泊中反嘴鹬的年平均数量与利用频次之间不存在显著相关性。自然保护区涵盖了反嘴鹬在鄱阳湖越冬的主要湖泊,分布在保护区内的反嘴鹬种群占鄱阳湖区越冬总数量的(75.3±26.0)%,但仍有很多重要的湖泊没有被纳入到保护区范围。反嘴鹬对保护区内湖泊的利用频次与保护区外湖泊的利用频次不存在显著性差异,保护区内反嘴鹬的种群数量显著大于保护区外。 相似文献
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Climate change has become a global issue influencing human survival and development while low‐carbon is the inevitable choice. As the world’s largest emitter of greenhouse gases, China has become an important force that influences the cooperation of climate change. China is a large agricultural country, and the rural carbon emissions have been gradually increasing. We consider rural neighborhood as an important space for the use of low‐carbon ideas to address climate change. There is no specific assessment system for a rural neighborhood. The studies of rural neighborhood low‐carbon mainly focus on the method of calculation carbon emissions. However, only quantifying rural carbon emissions is insufficient. In this paper, a low‐carbon evaluation indicator system has been proposed for rural neighborhood and Fuzzy Comprehensive Evaluation has been applied to get the low‐carbon degree. Considering the influence and feedback inside the indicator system, Analytic Network Process was applied to get the weights. Furthermore, a case study was carried out for the using of the proposed method in an eco‐village of China. Our practice has proved that the system is easy to operate in rural neighborhood. 相似文献
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The mud crab Scylla paramamosain is a widely farmed commercial species in southeast coastal areas of China. The crabs are placed in water-free containers for transportation to inland markets, thus are exposed to dry conditions for more than 72 h after capture and may suffer from air exposure stress, triggering cell apoptosis leading to death. To evaluate whether an inhibitor of apoptosis protein (IAP) is involved in apoptosis resistance against air exposure stress in crustaceans, SpIAP was cloned and investigated for the first time. The full length of SpIAP was 3351 bp, encoding a polypeptide of 662 amino acids. The predicted SpIAP protein contained three baculoviral IAP repeat domains and one really interesting new gene (RING) finger domain. Protein basic local alignment search tool and phylogenetic analysis results showed that SpIAP was clustered together with other crustaceans IAPs. SpIAP was detected in all the examined tissues and predominantly expressed in the hepatopancreas. When crabs were challenged with air exposure for 12 h, the expression level of SpIAP in the hepatopancreas was significantly increased in the experimental group compared with the control group. A RNA interference assay and flow cytometry analysis showed that when SpIAP was silenced, the cell apoptotic rate significantly increased after 24 h air exposure. These results suggested that SpIAP was involved in an anti-apoptosis response induced by air exposure in S. paramamosain. 相似文献
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Body fluid medical wastes are infectious clinical wastes (blood, saliva, urine) due to their high pathogenic content. Incineration is the most commonly used method in waste management that possess high water content along with molecularly dissolved species such as proteins. The process is costly; so that the removal of solid content dissolved in aqueous part by preliminary filtration can reduce the volume of the waste material. In this study, fibrous mats were prepared by electrospinning of PS wastes from DMF and THF solutions. Then they are employed in the removal of protein-based solid contents of body fluid medical wastes before their disposal. Two sources of PS waste (CD cover and Styrofoam) were employed along with virgin PS for comparison. The adsorption capacity of as-prepared electrospun fibers was examined for three model proteins: Bovine Serum Albumin (BSA), Myoglobin (MYO), and Trypsin (TRY). The fibers obtained from PS CD wastes have remarkably larger protein sorption capacities (particularly BSA) than the fibers obtained from virgin PS. XPS reveals the presence of CaCO3 domains in CD covers added into PS during their production steps probably to increase mechanical properties. There may be an electrostatic interaction between Ca2+ and the negatively charged groups of the protein. In this way, PS wastes could be converted to a beneficial secondary product by electrospinning and also resulting materials promises for the disposal of body fluid medical wastes. This may be one of the frontiers study on the removal of medical wastes by adsorbents produced via electrospinning of waste polymers. 相似文献
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ABSTRACT Aims: To assess the change in body condition score (BCS) during the early and late dry periods and its association with postpartum diseases and milk yield in grazing dairy cows from central Argentina. Methods: BCS assessments during the dry period, and cow health and milk production records up to 90 days in milk (DIM), were collated for cows from 28 farms at monthly visits between 2007 and 2008. Cows were categorised into four groups; those in Group 1 (n=7,067) maintained or gained BCS during the early and late dry periods; Group 2 (n=2,615) maintained or gained BCS during the early dry period and lost BCS during the late dry period; Group 3 (n=1,989) lost BCS during the early dry period and maintained or gained BCS during the late dry period; and Group 4 (n=5,144) lost BCS during the early and late dry periods. Results: Cows in Group 1 had reduced odds of having retained fetal membranes (RFM), metritis, and clinical mastitis up to 90 DIM than cows in Group 2 (p<0.001), but the odds of disease were similar to cows in Group 3. The odds of having RFM or clinical mastitis tended to be lower in cows in Group 1 than cows in Group 4 (p=0.08). The odds of cows being culled or dying during the first 90 DIM were lower for cows in Group 1 than for those in Groups 2, 3, and 4 (p≤0.05). Mean accumulated milk yield up to 90 DIM was higher in cows in Group 1 than Group 2 and Group 4 (p<0.001), but was similar to that of cows in Group 3 (p=0.28). Conclusions and clinical relevance: Cows that lost BCS during the late dry period had increased odds of being diagnosed with several postpartum diseases and had decreased milk yield compared to cows that maintained or gained BCS during the entire dry period. Loss of BCS during any stage of the dry period was also associated with increased incidence of culling or death during the first 90 DIM. These results should raise awareness among dairy cattle producers of the importance of properly managing cow body condition during the dry period, especially during the late dry period. 相似文献
10.
Chu Huangwei Tu Rongjian Niu Fuan Zhou Jihua Sun Bin Luo Zhongyong Cheng Can Cao Liming 《水稻科学》2021,28(1):6-10
Marker-assisted selection or marker-aided selection(MAS)provides an effective complementary approach for conventional rice breeding with precise and speedy mobilization of target genes into elite genetic backgrounds.The targeted genes,however,may not be selected in the course of MAS due to the occasional recombination between the marker and the target gene/QTL during the many cycles of meiosis involved in breeding programs.This leads to failure in the selection of target traits(Gopalakrishnan et al,2008). 相似文献