beef cattle

肉牛
  • 文章类型: Journal Article
    副结核病(PTB),或者是约翰的病,是由鸟分枝杆菌亚种引起的全球分布的疾病。导致慢性肠炎的副结核(MAP),主要是反刍动物。即使是亚临床感染也会显著降低动物的性能,和疾病的后果导致养牛业的高经济损失。为了估计牛PTB的经济负担并评估潜在控制程序的好处,需要准确估计与疾病相关的生产效应。因此,本次范围审查的目的是全面概述牛的MAP感染与生产参数之间的关联.这些研究是从三个电子数据库中收集的。在总共1,605项确定的研究中,在标题和摘要筛选中,有1,432个不符合设定的标准,在全文审查中排除了另外106个。最后,从67种出版物中提取了34种不同生产参数的数据。结果表明,报告的性能损失的大小取决于几个因素,例如所应用的诊断测试的类型,疾病状态或泌乳次数。研究报告牛奶产量下降,牛奶质量的变化(例如,更高的体细胞计数,生产的乳脂和蛋白质含量较低),生育力降低(例如,延长产卵间隔和服务期,较高的流产率和产卵困难),减少断奶重量,屠宰重量和屠宰价值,或者乳腺炎的风险更高。我们的综述中包括的研究结果显示,每头受感染的母牛的产奶量中位数下降,生奶牛的产奶量为-452kg/泌乳,模型数据的产奶量为-405kg/泌乳。同样,对于模型数据,产乳蛋白量的中位数下降-14.41kg/泌乳,产乳脂肪量的中位数下降-13.13kg/泌乳.审查的研究表明,在PTB阳性动物中,产卵间隔延长了约30天,每次泌乳的可能性高出1.5至3倍。本范围审查的结果为经济模型的开发提供了基于证据的输入,该模型旨在估算与PTB的不同疾病控制方案相关的成本和收益。
    Paratuberculosis (PTB), or Johne\'s disease, is a disease with worldwide distribution caused by Mycobacterium avium subsp. paratuberculosis (MAP) that leads to chronic enteritis, primarily in ruminants. Even subclinical infection significantly reduces the animals\' performance, and consequences of the disease lead to high economic losses for the cattle industry. To estimate the economic burden of bovine PTB and to evaluate the benefits of a potential control program, accurate estimates of the production effects associated with the disease are required. Therefore, the aim of this scoping review was to provide a comprehensive overview of associations between MAP infection and production parameters in cattle. The studies were collected from three electronic databases. Of the total 1,605 identified studies, 1,432 did not meet the set criteria in the title and abstract screening and a further 106 were excluded during full-text review. Finally, data on 34 different production parameters were extracted from 67 publications. Results show that the magnitude of reported performance losses varies depending on several factors, such as the type of diagnostic test applied, disease status or number of lactations. Studies reported a reduction in milk yield, changes in milk quality (e.g., higher somatic cell count, lower amount of produced milk fat and protein), reduced fertility (e.g., prolonged calving interval and service period, higher abortion rate and calving difficulties), reduced weaning weight, slaughter weight and slaughter value, or a higher risk for mastitis. Results from the studies included in our review show a median decrease of milk yield per infected cow of -452 kg/lactation for raw and -405 kg/lactation for modeled data. Similarly, the amount of produced milk protein fell by a median of -14.41 kg/lactation for modeled data and the amount of produced milk fat by a median of -13.13 kg/lactation. The reviewed studies revealed a prolonged calving interval by around 30 days and a 1.5 to 3 times higher likeliness of culling per lactation in PTB positive animals. Results from this scoping review provide evidence-based inputs for the development of economic models aiming at the estimation of the costs and benefits associated with different disease control scenarios for PTB.
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  • 文章类型: Journal Article
    肌内脂肪(IMF)沉积对肉牛生产中的肉质量和经济价值产生了深远的影响。同时,表观遗传学的当代发展为理解国际货币基金组织监管的分子基础开辟了新的前景,它已经成为世界学者研究的重点领域。因此,本文的目的是提供有关肉牛表观遗传机制与IMF沉积之间复杂关系的见解和综合。该方法涉及对现有文献的彻底分析,包括相关的书籍,学术期刊,和在线资源,全面概述表观遗传研究在肉牛IMF沉积中的作用。这篇综述总结了IMF调控中表观遗传机制的当代研究,高分辨率表观基因组作图,单细胞表观基因组学,多组学整合,表观基因组编辑方法,牛生长的纵向研究,环境表观遗传学,表观遗传学中的机器学习,道德和监管方面的考虑,并从IMF在肉牛中的沉积角度转化为行业实践。此外,本文重点介绍了DNA甲基化,组蛋白修饰,乙酰化,磷酸化,泛素化,非编码RNA,DNA羟甲基化,表观遗传读者,作家,和橡皮擦,染色质免疫沉淀,然后测序,全基因组亚硫酸氢盐测序,全表观基因组关联研究,以及它们对控制脂肪生成和脂质代谢的关键基因表达的深远影响。营养和应激对表观遗传修饰和IMF沉积也有显著影响。主要发现强调了表观遗传学研究在理解和增强肉牛中IMF沉积方面的关键作用,对精准畜牧业和伦理畜牧业管理具有重要意义。总之,这篇综述强调了表观遗传途径和环境因素在影响肉牛IMF沉积中的重要意义,为提高牛生产的经济性和肉质提供有见地的信息。
    Intramuscular fat (IMF) deposition profoundly influences meat quality and economic value in beef cattle production. Meanwhile, contemporary developments in epigenetics have opened new outlooks for understanding the molecular basics of IMF regulation, and it has become a key area of research for world scholars. Therefore, the aim of this paper was to provide insight and synthesis into the intricate relationship between epigenetic mechanisms and IMF deposition in beef cattle. The methodology involves a thorough analysis of existing literature, including pertinent books, academic journals, and online resources, to provide a comprehensive overview of the role of epigenetic studies in IMF deposition in beef cattle. This review summarizes the contemporary studies in epigenetic mechanisms in IMF regulation, high-resolution epigenomic mapping, single-cell epigenomics, multi-omics integration, epigenome editing approaches, longitudinal studies in cattle growth, environmental epigenetics, machine learning in epigenetics, ethical and regulatory considerations, and translation to industry practices from perspectives of IMF deposition in beef cattle. Moreover, this paper highlights DNA methylation, histone modifications, acetylation, phosphorylation, ubiquitylation, non-coding RNAs, DNA hydroxymethylation, epigenetic readers, writers, and erasers, chromatin immunoprecipitation followed by sequencing, whole genome bisulfite sequencing, epigenome-wide association studies, and their profound impact on the expression of crucial genes governing adipogenesis and lipid metabolism. Nutrition and stress also have significant influences on epigenetic modifications and IMF deposition. The key findings underscore the pivotal role of epigenetic studies in understanding and enhancing IMF deposition in beef cattle, with implications for precision livestock farming and ethical livestock management. In conclusion, this review highlights the crucial significance of epigenetic pathways and environmental factors in affecting IMF deposition in beef cattle, providing insightful information for improving the economics and meat quality of cattle production.
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  • 文章类型: Journal Article
    需要对肉类生产动物进行先进和创新的育种和管理,以应对全球粮食安全和可持续性挑战。牛肉生产是确保世界动物蛋白质资源的重要产业,肉类质量极大地促进了经济价值和人类需求。提高牛的饲料效率已成为当务之急,因为它可以降低甲烷气体排放的环境负担和减少人类食用谷物的消耗。牛依靠其共生微生物组及其在瘤胃和肠道中的活性来维持生长和健康。高通量组学分析的最新进展(宏基因组,metaranscriptome,代谢组,元蛋白质组等)使得全面分析微生物组成为可能,宿主及其相互作用,并定义它们在影响牛生物学中的作用。在这次审查中,我们专注于肠道微生物组和牛肉品质之间的关系,饲料效率,甲烷排放以及肉牛的宿主遗传学,旨在确定当前的知识差距,以制定提高牛肉生产可持续性的策略。
    Advanced and innovative breeding and management of meat-producing animals are needed to address the global food security and sustainability challenges. Beef production is an important industry for securing animal protein resources in the world and meat quality significantly contributes to the economic values and human needs. Improvement of cattle feed efficiency has become an urgent task as it can lower the environmental burden of methane gas emissions and the reduce the consumption of human edible cereal grains. Cattle depend on their symbiotic microbiome and its activity in the rumen and gut to maintain growth and health. Recent developments in high-throughput omics analysis (metagenome, metatranscriptome, metabolome, metaproteome and so on) have made it possible to comprehensively analyze microbiome, hosts and their interactions and to define their roles in affecting cattle biology. In this review, we focus on the relationships among gut microbiome and beef meat quality, feed efficiency, methane emission as well as host genetics in beef cattle, aiming to determine the current knowledge gaps for the development of the strategies to improve the sustainability of beef production.
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  • 文章类型: Journal Article
    在过去的几十年里,基因组选择和其他完善的策略已用于提高肉牛的生长速度和瘦肉产量。然而,牛品种的快速生长速度通常伴随着肌内脂肪(IMF)沉积的减少,损害肉质。转录因子在调节肉牛脂肪生成和脂肪生成中起着至关重要的作用。同时,了解转录因子在调节肉牛脂肪生成和脂肪生成中的作用,已引起人们对增加IMF沉积和肉质的关注。因此,本文的目的是对肉牛脂肪生成和脂肪生成中转录因子的复杂作用进行全面的总结和有价值的见解。本文综述了转录因子在脂肪生成和脂肪生成中的当代研究。转录因子的全基因组分析,转录因子的表观遗传调控,转录因子的营养调节,代谢信号通路,功能基因组学方法,脂肪组织的转录组学分析,转录因子和肉质以及与其他家畜物种的比较基因组学。总之,转录因子在促进肉牛脂肪细胞发育和脂肪酸合成中起着至关重要的作用。它们控制脂肪组织的形成和代谢,从而改善肉质和维持代谢平衡。了解这些转录因子调节脂肪组织沉积和脂质代谢的过程将简化肉牛中大理石花纹或IMF成分的发展。
    In the past few decades, genomic selection and other refined strategies have been used to increase the growth rate and lean meat production of beef cattle. Nevertheless, the fast growth rates of cattle breeds are often accompanied by a reduction in intramuscular fat (IMF) deposition, impairing meat quality. Transcription factors play vital roles in regulating adipogenesis and lipogenesis in beef cattle. Meanwhile, understanding the role of transcription factors in regulating adipogenesis and lipogenesis in beef cattle has gained significant attention to increase IMF deposition and meat quality. Therefore, the aim of this paper was to provide a comprehensive summary and valuable insight into the complex role of transcription factors in adipogenesis and lipogenesis in beef cattle. This review summarizes the contemporary studies in transcription factors in adipogenesis and lipogenesis, genome-wide analysis of transcription factors, epigenetic regulation of transcription factors, nutritional regulation of transcription factors, metabolic signalling pathways, functional genomics methods, transcriptomic profiling of adipose tissues, transcription factors and meat quality and comparative genomics with other livestock species. In conclusion, transcription factors play a crucial role in promoting adipocyte development and fatty acid biosynthesis in beef cattle. They control adipose tissue formation and metabolism, thereby improving meat quality and maintaining metabolic balance. Understanding the processes by which these transcription factors regulate adipose tissue deposition and lipid metabolism will simplify the development of marbling or IMF composition in beef cattle.
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  • 文章类型: Journal Article
    牛肉品质的特点是大理石花纹(大理石花纹程度和大理石花纹细度),物理化学(剪切力,肉的颜色,脂肪的颜色,纹理,和成熟度),和感官(压痛,风味,多汁,味道,气味,和外观)特征。本文总结并讨论了韩国牛肉的质量特征和牛肉分级系统,Japan,美国,和澳大利亚。本文综述了影响牛肉品质的遗传和营养因素的最新研究进展。肌内(i.m.)脂肪组织沉积或大理石花纹是牛肉质量的主要决定因素。本文探讨了i.m.脂肪组织沉积的机制,重点是脂肪生成和脂肪生成。我们还讨论了与i.m.脂肪组织沉积相关的选定信号通路。营养素通过基因表达和代谢促进细胞反应和表型。本文讨论了通过几种营养素(碳水化合物,脂肪/脂肪酸,维生素,等。)用于i.m.脂肪组织沉积。解决了通过营养素负责基因表达的几种转录因子。我们介绍了韩国牛基于基因组的精确喂养的概念。
    Beef quality is characterized by marbling (marbling degree and marbling fineness), physiochemical (shear force, meat color, fat color, texture, and maturity), and sensory (tenderness, flavor, juiciness, taste, odor, and appearance) traits. This paper summarizes and addresses beef-quality characteristics and the beef-grading systems in Korea, Japan, the USA, and Australia. This paper summarizes recent research progresses on the genetic and nutritional factors that affect beef quality. Intramuscular (i.m.) adipose tissue deposition or marbling is a major determinant of beef quality. This paper addresses the mechanisms of i.m. adipose tissue deposition focused on adipogenesis and lipogenesis. We also address selected signaling pathways associated with i.m. adipose tissue deposition. Nutrients contribute to the cellular response and phenotypes through gene expression and metabolism. This paper addresses control of gene expression through several nutrients (carbohydrates, fat/fatty acids, vitamins, etc.) for i.m. adipose tissue deposition. Several transcription factors responsible for gene expression via nutrients are addressed. We introduce the concept of genome-based precision feeding in Korean cattle.
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  • 文章类型: Journal Article
    改革开放以来,中国的肉牛产业取得了长足发展。中国已经成为世界第三大肉牛生产国。中国也是肉牛饲料和营养领域研究投入和产出最多的国家之一。我国在肉牛饲料和营养研究领域的进步和创新无疑促进了国内肉牛产业的发展。这篇综述总结了饲料资源开发的最新进展,营养需求,和中国肉牛的营养调控。还讨论了当前研究的局限性和对未来工作的看法。
    The beef cattle industry in China has advanced remarkably since its reform and opening up; consequently, China has become the world\'s third-largest beef cattle producer. China is also one of the countries with the most substantial research input and output in the field of beef cattle feed and nutrition. The progress and innovation by China in the research field of beef cattle feed and nutrition have undoubtedly promoted the development of the domestic beef cattle industry. This review summarizes recent advances in feed resource development, nutrient requirements, and nutritional regulation of beef cattle in China. Limitations in current research and perspectives on future work are also discussed.
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  • 文章类型: Journal Article
    大约70%的牛肉生产成本受到饮食摄入的影响。肉牛的生产效率最大化不仅需要遗传选择来最大化饲料效率(即,残余饲料摄入量(RFI)),而且在生长和发育的所有阶段都有足够的营养,以最大限度地提高生长效率和生殖能力,即使在怀孕期间。RFI作为衡量牛饲料效率的指标最近已被接受并用于牛肉行业。但是选择RFI对妊娠动力学的影响尚未得到广泛研究,特别是在大坝和胎儿的能量供应波动的情况下。妊娠期间的营养限制已被证明会对出生后的生长发育以及肉牛后代的生育能力产生负面影响。这个,当与RFI的遗传潜力相结合时,可能会显着影响后代的能量分配以及随后的重要性能特征。在这次审查中,我们讨论:1)RFI作为饲料效率的衡量指标的重要性以及它如何影响肉牛的其他经济性状;2)产前营养对小牛生理表型的影响;3)研究RFI遗传选择与产前营养相互作用的益处;4)代谢组学,转录组学,和表观基因组学已被用来研究与产前营养相关的潜在生物学,RFI,或它们在肉牛中的相互作用;5)组学信息的整合如何增加对牛表型性状遗传结构的更深入理解。
    Approximately 70% of the cost of beef production is impacted by dietary intake. Maximizing production efficiency of beef cattle requires not only genetic selection to maximize feed efficiency (i.e., residual feed intake (RFI)), but also adequate nutrition throughout all stages of growth and development to maximize efficiency of growth and reproductive capacity, even during gestation. RFI as a measure of feed efficiency in cattle has been recently accepted and used in the beef industry, but the effect of selection for RFI upon the dynamics of gestation has not been extensively studied, especially in the context of fluctuating energy supply to the dam and fetus. Nutrient restriction during gestation has been shown to negatively affect postnatal growth and development as well as fertility of beef cattle offspring. This, when combined with the genetic potential for RFI, may significantly affect energy partitioning in the offspring and subsequently important performance traits. In this review, we discuss: 1) the importance of RFI as a measure of feed efficiency and how it can affect other economic traits in beef cattle; 2) the influence of prenatal nutrition on physiological phenotypes in calves; 3) the benefits of investigating the interaction of genetic selection for RFI and prenatal nutrition; 4) how metabolomics, transcriptomics, and epigenomics have been employed to investigate the underlying biology associated with prenatal nutrition, RFI, or their interactions in beef cattle; and 5) how the integration of omics information is adding a level of deeper understanding of the genetic architecture of phenotypic traits in cattle.
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  • 文章类型: Journal Article
    目的是进行系统评价,以评估饮食中补充β-肾上腺素能激动剂对牛肌肉中钙蛋白酶和钙蛋白酶原活性的影响以及肉嫩度的变化。2019年6月对ScienceDirect进行了一项调查,WebofScience,Scopus,PubMed和Capes期刊,使用四个关键词组合:激动剂和钙蛋白酶和牛;激动剂和钙蛋白酶和牛;激动剂和钙蛋白酶和小母牛;激动剂和钙蛋白酶和牛。选择了13项研究,54%的人得出结论,补充β-肾上腺素能激动剂会增加钙蛋白酶抑制素的活性,23%观察到它们的基因表达增加,23%报道对该酶的活性或表达没有影响。九项研究评估了补充β-肾上腺素能激动剂对肉质的影响,所有研究都发现剪切力值增加。有强有力的证据表明,β-肾上腺素能激动剂可能会增加肌肉中的钙蛋白酶原活性,对肉的嫩度造成损害。
    The objective was to conduct a systematic review to evaluate the effects of dietary supplementation with beta-adrenergic agonists on calpains and calpastatin activity in bovine muscle and changes in meat tenderness. A survey was conducted in June 2019 on Science Direct, Web of Science, Scopus, PubMed and Capes Periodicals, using four keyword combinations: agonist and calpain and cattle; agonist and calpain and bovine; agonist and calpain and heifers; agonist and calpain and steers. Thirteen studies were selected, 54% concluded that supplementation with beta-adrenergic agonists increases calpastatin activity, 23% observed increase in their gene expression and 23% reported no effect on activity or expression of this enzyme. Nine studies evaluated the influence of beta-adrenergic agonists supplementation on meat texture and all found an increase in shear force values. There is strong evidence that beta-adrenergic agonists may increase calpastatin activity in the muscle, causing damage to meat tenderness.
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  • 文章类型: Journal Article
    背景:由于气候变化而增加的天气不确定性和变异性给美国大陆几个地区的农业社区的可持续性带来了巨大压力。农村农业社区,比如北卡罗来纳州的那些,内布拉斯加州,和伊利诺伊州特别容易受到洪水的影响。这些极端天气事件影响了许多动物设施,洪水会对动物健康和生产力造成长期影响。
    目的:这项范围界定审查调查了洪水对美国中西部具有理论位置的肉牛和猪场的潜在短期和长期影响。这项审查的目的是创建一个概念图,以确定与支持遭受洪水破坏的动物和人民的努力有关的研究空白。这是通过使用搜索词“牛肉或猪和洪水”进行范围审查来评估直接影响,然后使用“牛肉或猪和直接影响”来评估二级和三级影响。
    结果:我们的发现基于89篇同行评审的出版物,有50份有关肉牛的出版物,24与猪有关,和15包含适用于两者的信息。在牛肉农场,洪水的影响可能是广泛而持久的。洪水的短期风险得到了合理的理解,包括饲养不熟悉的牛,营养限制,和疾病传播。然而,长期影响,包括对繁殖的潜在影响,营养,和car体质量,研究较少。特别是,需要对洪水后污染干草的霉菌物种进行进一步研究,发霉的干草摄入对牛的影响,以及重金属消费对牛和消费者的影响。关于洪水对猪场的影响的研究很少,可能是由于猪操作的高度密集性。总的来说,洪水事件后,猪场遭受急性传染病和生物安全风险。
    结论:洪灾对牲畜农场的潜在影响因农场经营而异。牛肉养殖场应该为营养和繁殖的长期影响做好准备,而养猪场应该为生物安全的短期影响做好准备。
    BACKGROUND: Increasing uncertainty and variability in weather due to climate change puts enormous stress on the sustainability of agricultural communities in several parts of the continental United States. Rural agriculture-based communities, such as those in North Carolina, Nebraska, and Illinois are particularly vulnerable to the impacts of flooding. These extreme weather events affect many animal facilities, and flooding can cause long-term impacts on animal health and productivity.
    OBJECTIVE: This scoping review investigated the potential short- and long-term ramifications of flooding on beef cattle and swine farms with theoretical locations in the Midwestern U.S. The goal of this review is to create a concept map to identify research gaps related to efforts to support those animals and peoples ravaged by floods. This was accomplished by performing a scoping review using search terms \"beef OR swine AND flood\" to assess direct effects and then \"beef OR swine AND direct effect\" to evaluate secondary and tertiary effects.
    RESULTS: Our findings were based on a total of 89 peer-reviewed publications, with 50 publications relating to beef cattle, 24 relating to swine, and 15 containing information applicable to both. On beef farms, the effects of flooding can be broad and long-lasting. The short-term risks of flooding are reasonably well-understood, including the comingling of unfamiliar cattle, nutritional restriction, and disease transmission. However, long-term impacts, including potential effects on reproduction, nutrition, and carcass quality, have been less studied. In particular, further research is needed on mold species that contaminate hay post-flood, the effect of moldy hay ingestion on cattle, and the effects of heavy metal consumption on cattle and consumers. Little research is available regarding the effects of flooding on swine farms, likely due to the highly intensive nature of swine operations. In general, swine farms suffer from acute infectious diseases and biosecurity risks after flooding events.
    CONCLUSIONS: The potential ramifications of flooding on livestock farms differ among farm operations. Beef farms should prepare for long-term impacts on nutrition and reproduction, while swine farms should prepare for short-term impacts on biosecurity.
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  • 文章类型: Journal Article
    住房系统和环境特征会影响肉牛福利。迄今为止,关于这个主题的信息很少。这次范围审查的目的是研究住房和福利状况之间的关系,这样肉牛生产者和动物科学家就他们的住房选择如何影响肉牛福利做出明智的决定。住房功能按地板类型分类,空间裕度和阴凉处的可用性,以及包括浓缩装置或通风功能。当每只动物饲养2.5m2至3.0m2的牛时,对整个饲养场环境的空间配额的评估确定了行为和生产效益。对超过19种不同的地板类型进行了调查,并跨越了地板类型;从行为上看,稻草地板被认为是最有利的,生产和卫生的立场。小牛经历了增强的福利(例如,改善行为,生理,和绩效指标)在组住时。有证据表明,实施渐进式住房改造(例如,shade,环境富集)可以促进饲养牛的行为福利。这篇综述介绍了特定住房特征对肉牛福利的利弊。
    Housing systems and environmental features can influence beef cattle welfare. To date, little information has been synthesized on this topic. The aim of this scoping review was to examine the relationship between housing and welfare status, so that beef cattle producers and animal scientists can make informed decisions regarding how their housing choices could impact beef cattle welfare. Housing features were categorized by floor type, space allowance and shade availability, as well as the inclusion of enrichment devices or ventilation features. Evaluation of space allowances across feedlot environments determined behavioral and production benefits when cattle were housed between 2.5 m2 to 3.0 m2 per animal. Over 19 different flooring types were investigated and across flooring types; straw flooring was viewed most favorably from a behavioral, production and hygiene standpoint. Veal calves experience enhanced welfare (e.g., improved behavioral, physiological, and performance metrics) when group housed. There is evidence that the implementation of progressive housing modifications (e.g., shade, environmental enrichment) could promote the behavioral welfare of feedlot cattle. This review presents the advantages and disadvantages of specific housing features on the welfare of beef cattle.
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