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1.
Gerrits RJ Lunney JK Johnson LA Pursel VG Kraeling RR Rohrer GA Dobrinsky JR 《Theriogenology》2005,63(2):283-299
Civilizations throughout the world continue to depend on pig meat as an important food source. Approximately 40% of the red meat consumed annually worldwide (94 million metric tons) is pig meat. Pig numbers (940 million) and consumption have increased consistent with the increasing world population (FAO 2002). In the past 50 years, research guided genetic selection and nutrition programs have had a major impact on improving carcass composition and efficiency of production in swine. The use of artificial insemination (AI) in Europe has also had a major impact on pig improvement in the past 35 years and more recently in the USA. Several scientific advances in gamete physiology and/or manipulation have been successfully utilized while others are just beginning to be applied at the production level. Semen extenders that permit the use of fresh semen for more than 5 days post-collection are largely responsible for the success of AI in pigs worldwide. Transfer of the best genetics has been enabled by use of AI with fresh semen, and to some extent, by use of AI with frozen semen over the past 25 years. Sexed semen, now a reality, has the potential for increasing the rate of genetic progress in AI programs when used in conjunction with newly developed low sperm number insemination technology. Embryo cryopreservation provides opportunities for international transport of maternal germplasm worldwide; non-surgical transfer of viable embryos in practice is nearing reality. While production of transgenic animals has been successful, the low level of efficiency in producing these animals and lack of information on multigene interactions limit the use of the technology in applied production systems. Technologies based on research in functional genomics, proteomics and cloning have significant potential, but considerable research effort will be required before they can be utilized for AI in pig production. In the past 15 years, there has been a coordinated worldwide scientific effort to develop the genetic linkage map of the pig with the goal of identifying pigs with genetic alleles that result in improved growth rate, carcass quality, and reproductive performance. Molecular genetic tests have been developed to select pigs with improved traits such as removal of the porcine stress (RYR1) syndrome, and selection for specific estrogen receptor (ESR) alleles. Less progress has been made in developing routine tests related to diseases. Major research in genomics is being pursued to improve the efficiency of selection for healthier pigs with disease resistance properties. The sequencing of the genome of the pig to identify new genes and unique regulatory elements holds great promise to provide new information that can be used in pig production. AI, in vitro embryo production and embryo transfer will be the preferred means of implementing these new technologies to enhance efficiency of pig production in the future. 相似文献
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The action of snake venom phospholipases A2 in intact human erythrocytes was investigated in detail. The basis phospholipase from Agkistrodon halys blomhifii was found to induce both hydrolysis of membrane phospholipids and total cell hemolysis under certain experimental conditions. The hydrolytic action of the basic enzyme was found to consist of two sequential events: (a) hydrolysis of 70% of the total cell ph osphatidylcholine without any evident hemolysis; and (b) complete hydrolysis of the remaining phosphatidylcholine, followed closely by extensive phosphatidylethanolamine hydrolysis and finally with onset of hemolysis, attack on the phosphatidylserine. At pH 7.4 and 10 mM Ca2+ only stage (a) occurred. However, a slight elevation of the pH of incubation to pH 8.0 and/or inclusion of 40 mM Ca2+ in the reaction mixture caused both events (a) and (b) to occur. The addition of glucose limited the action of the enzyme to stage (a) under any reaction conditions. An investigation showed that enzymically induced hemolysis occurred under conditions where the intracellular ATP levels were lowered. Data are presented which suggest that stage (b) is mediated by in influx of Ca2+ into the cell when the levels of ATP are low. Interestingly the phosphllipase from Naja naja venom (Pakistan) yielded results similar to those observed with the basic enzyme from Agkistrodon venom. However, the enzyme from Crotalus adamanteus and the acidic enzyme also present in the Agkistrodon venom produced only slight hydrolysis or hemolysis under any of the conditions studied. Other species of erythrocytes, e.g., guinea pig, monkey, pig, and rat, were tested but only those from guinea pig behaved similarly to the human cells. Pig, monkey, and rat erythrocytes underwent very limited hydrolysis and hemolysis. It is evident that the use of these phospholipases to probe the localization of phospholipds in erythrocyte membranes must be approached with caution. Certain facets of this problem are discussed. 相似文献
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Siffel C Strickland MJ Gardner BR Kirby RS Correa A 《Birth defects research. Part A, Clinical and molecular teratology》2006,76(11):825-833
BACKGROUND: With the significant advancement of geographic information systems (GIS), mapping and evaluating the spatial distribution of health events has become easier. We examine the role of GIS in birth defects surveillance and research. METHODS: We briefly describe the geocoding process and potential problems in accuracy of the obtained geocodes, and some of the capabilities and limitations of GIS. We illustrate how GIS has been applied using the Metropolitan Atlanta Congenital Defects Program geocoded dataset. We provide some comments on potential data quality and confidentiality issues with birth defects in relation to GIS. RESULTS: It is desirable to geocode addresses using a multistrategy approach to achieve a high-quality and accurate GIS dataset. Beyond the basic but important function of mapping, sophisticated statistical approaches and software are available to analyze the spatial or spatial-temporal occurrence of birth defects, alone or in association with environmental hazards, and to present this information without compromising the confidentiality of the subjects. CONCLUSIONS: We recommend a broad and systematic use of GIS in birth defects spatial surveillance and research. 相似文献
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猪脂肪及肌肉组织中基因表达信息分析 总被引:1,自引:0,他引:1
为探测猪脂肪及肌肉组织中基因表达概况,利用猪EST资源和人类基因序列开展计算机模拟研究,旨在为猪肉质改良的遗传基础分析提供候选信息。执行Blast比对程序以识别人类基因组基因与猪EST序列间的同源性并筛选出高度同源记录,同时编制4个Java程序进行序列检索收集、序列比对结果的过滤筛选以及分类处理。统计分析表明:至少有2002个基因在猪脂肪及肌肉组织中表达,其中1087个基因在脂肪组织表达,1205个基因在肌肉组织中表达,两组织共同表达的基因为290个;筛选出高同源基因,同时分类统计出了114个基础活性基因(脂肪和肌肉组织分别表达80和34个),并选取Top记录进行了描述分析和总结。 相似文献
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Cooper TK Gabrielson KL 《Birth defects research. Part B, Developmental and reproductive toxicology》2007,80(2):149-170
Because of their close phylogenic relationship with humans, the use of non-human primates (NHP) as experimental subjects has a long history in biomedical research. Although research topics have shifted focus and species used have changed, NHP remain vital as models in basic and applied research. While there is a wealth of information available on the spontaneous lesions of NHP, most of this information is fragmented, dated, or narrow in focus, often limited to single case reports. This review attempts to integrate this information to illustrate and enumerate the spectrum of spontaneous pathology of the reproductive tract and mammary gland of NHP. Although not the focus of this review, steroid-related changes are inextricably linked to these tissues, and brief consideration is given to this subject as well. 相似文献
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Importance of basic research in applied phycology 总被引:1,自引:0,他引:1
Utilization of algae has extended considerably from the middle of this century, with the consequence of more and more applied research in various directions and fields, the most important of which deals with phycocolloid production and algal cultivation to provide raw material and foodstuff. It is noteworthy that this research can not avoid the use of knowledge obtained by basic research; applied phycology is especially indebted to basic research in adopting biotechnologies which are typically coming from basic research. In counterpart, such a situation is beneficial to basic research. According to the dependence of applied phycology to basic research and the fact that restricted research programs only are nowadays financially supported, the fate of all research seems to be questionable. 相似文献
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Young-Joo Jeon Jumi Kim Jung-Il Chae 《In vitro cellular & developmental biology. Animal》2013,49(5):315-323
The development of the kidney is a complex process that serves as a model organ system for understanding many basic developmental mechanisms, and the pig kidney provides a useful and relevant model of kidney development and function. However, the molecular cascades involved in kidney development during embryonic development in the pig have not been elucidated fully. To better understand the molecular events associated with kidney development, we evaluated changes in gene expression during kidney development (days E40, E70, and E93) and compared these expressions with adults using two-dimensional gel electrophoresis. The functionally regulated proteins were identified by comparing differentially expressed proteins in embryonic kidneys vs. adult kidney. In addition, a representative set of the proteins was subjected to liquid chromatography tandem mass spectrometry analysis. Furthermore, the identified proteins were categorized according to their biological processes and molecular functions. Interestingly, 10 of the 25 proteins identified were apoptosis and actin cytoskeleton-related proteins, such as GRP75, α-fetoprotein, ANXA2, ANXA4, DDAH2, DJ-1, SOD2, cofilin1, vil1, and calbindin1. Based on these results, the proteomic approach was applied to identify specific protein expression changes in kidney tissues during development, and the expressional changes of these embryonic kidney proteins were found to be closely associated with the regulation of kidney development. 相似文献
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GIS支持下的青石山小流域农业生态信息系统(QWAEIS)及其应用研究 总被引:13,自引:2,他引:11
应用地理信息系统(GIS),建立了青石山小流域农业生态信息系统(QWAEIS),该系统综合了土壤、土地利用、水资源及地形地貌等空间信息和气候、人口、农业生产等基本信息。该系统能对小流域农业生态信息进行有效地分析和管理,应用此系统,进行了小流域的土地适宜性评价,获得土地适宜性评价结果,为小流域规划提供了空间定位信息。 相似文献
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细胞动态过程的研究表明,细胞在动态过程中会发生状态变化,主要由细胞内部的基因表达情况控制.随着高通量测序技术的发展,大量的基因表达数据能够在单细胞水平上获得细胞真实的基因表达信息.然而,现有大多数研究方法需要使用除基因表达以外其他的信息,带来了额外的复杂度和不确定性.此外,普遍存在的"缺失值"事件更是影响了对细胞动态发... 相似文献
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《Animal : an international journal of animal bioscience》2019,13(11):2699-2713
The purpose of this review is to offer a panorama on 10 years of nutrition research using in vivo brain imaging in the pig model. First, we will review some work describing the brain responses to food signals, including basic tastants such as sweet and bitter at both oral and visceral levels, as well as conditioned preferred and aversive flavours. Second, we will have a look at the impact of weight gain and obesity on brain metabolism and functional responses, drawing the parallel with obese human patients. Third, we will evoke the concept of the developmental origins of health and diseases, and how the pig model can shed light on the importance of maternal nutrition during gestation and lactation for the development of the gut–brain axis and adaptation abilities of the progeny to nutritional environments. Finally, three examples of preventive or therapeutic strategies will be introduced: the use of sensory food ingredients or pre-, pro-, and postbiotics to improve metabolic and cognitive functions; the implementation of chronic vagus nerve stimulation to prevent weight gain and glucose metabolism alterations; and the development of bariatric surgery in the pig model for the understanding of its complex mechanisms at the gut–brain level. A critical conclusion will brush the limitations of neurocognitive studies in the pig model and put in perspective the rationale and ethical concerns underlying the use of pig experimentation in nutrition and neurosciences. 相似文献
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Friedmann T 《Perspectives in biology and medicine》2005,48(4):585-591
The discovery of human embryonic stem cells has pointed to the potential use of these cells in developing new approaches to therapy for many major human diseases. While there is general agreement that such applications are possible and will require a great deal of additional basic and preclinical research, some discussions of the therapeutic applications of human embryonic stem cells have been characterized by the kinds of exaggerations and elevated expectations that characterized the field of human gene therapy a decade ago. In the case of gene therapy, public perception of and confidence in the field were damaged by the hype. Most unfortunate of all, the hopes of patients and their advocates were disappointed. The eventual success of a gene therapy approach, albeit one still plagued by serious adverse events, has come through scientific advance and careful clinical application. The probable eventual use of human embryonic stem cells for therapy of human disease will also require thorough basic and clinical research, but that goal is endangered by the current level of inaccurate representations and undeliverable promises. 相似文献
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Shinsuke Nakai 《Human ecology: an interdisciplinary journal》2009,37(4):501-511
Previous studies on the hillside farmers of northern Thailand often focused on their swidden (slash-and-burn) agriculture
of upland rice and cash crop cultivation and paid little attention to livestock production and consumption, including that
of pigs. I describe the household-level pig production and consumption in terms of the number of pigs slaughtered and the
number of pigs supplied to others, or acquired from others, in a Hmong village of smallholders in northern Thailand. Study
results are based on pig consumption in 17 selected households over two years (January 2005 to December 2006). The number
of pigs slaughtered in each household ranged from zero to ten, with an average of 2.4 pigs per household per year. Pigs were
slaughtered mainly for ritual events, particularly for annual ancestor worship and New Year ceremonies. A total of 80 pigs
were slaughtered, with 78% being killed during ritual events including Christmas and 22% for non-ritual events including children
moving up a grade in school. Most Christian households stopped slaughtering of pigs in ancestor worship conducted by a shaman,
but continued to do so in Christmas and New Year rituals. A total of 23 pigs were supplied to others, of which two were given
to people outside the village, while of a total of 37 pigs acquired, 17 were obtained from outside the village. A total of
80 pigs were slaughtered, including one improved-breed pig that was killed during a marriage ceremony soon after it was acquired
from the city. The following changes in pig consumption are inferred to have taken place due to recent socioeconomic changes:
(1) diversification of the type of events in which pigs are slaughtered as a result of the introduction of Christianity and
the national educational system; (2) active pig acquisition from outside the village as a result of the use of motor vehicles;
and (3) the acquisition and slaughtering for events of improved-breeds of pigs which are not kept and used for breeding. 相似文献
15.
Jin He Jianhua Ye Qiuyan Li Yuanyuan Feng Xueyuan Bai Xiangmei Chen Changxin Wu Zhengquan Yu Yaofeng Zhao Xiaoxiang Hu Ning Li 《Transgenic research》2013,22(4):861-867
Autosomal dominant polycystic kidney disease (ADPKD) is a common human genetic disease, affecting millions of people worldwide. The progressive growth of cysts in kidneys eventually leads to renal failure in 50 % of patients, and there is currently no effective treatment. Various murine models have been studied to elucidate the disease mechanisms, and much information has been acquired. However, the course of the disease cannot be fully recapitulated using these models. The pig is a suitable model for biomedical research, and pig PKD2 has high similarity to the human ortholog at the molecular level. Here, a mini-pig PKD2 transgenic model was generated, driven by a ubiquitous cytomegalovirus enhancer/promoter. Using somatic cell nuclear transfer, four transgenic pigs with approximately 10 insertion events each were generated. Quantitative real-time PCR and western blotting showed that PKD2 was more highly expressed in transgenic pigs than in wild-type counterparts. Because of the chronic nature of ADPKD, blood urea nitrogen and serum creatinine levels were continuously measured to assess the pig kidney function. The transgenic pigs continue to show no significant alteration in kidney function; it is estimated that 1–2 more years may be required for manifestation of renal cystogenesis in these pigs. 相似文献
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AM Jefcoat 《Lab animal》2012,41(9):260-263
In an animal care and use program in a research setting, events that have a negative impact on animal well-being do not typically occur spontaneously and arbitrarily. It takes the convergence of multiple missteps, miscalculations and misinterpretations of conditions for a serious accident to take place. Two concepts drawn from wilderness survival training can be applied to any research animal care and use program to reduce adverse events. The first, derived from the accident matrix model, is the concept of 'problem vectors,' or conditions, behaviors and policies that increase the likelihood of an adverse event. Identifying problem vectors and diverting them before they intersect to create an adverse event can considerably improve animal well-being and reduce the number of protocol violations and reportable events. The second concept is that of doing the 'next right thing' when an adverse event does occur in an animal program. The next right thing is a response characterized by unified directed action toward fixing problems without engaging in behaviors that might worsen the situation. Adopting an institution-wide approach of diverting problem vectors and pursuing the next right thing can result in better prevention and management of adverse events. 相似文献
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Cell adhesion and cell migration are two primary cellular phenomena to be approached in vitro in order to allow for the effective
dissection of the individual events and the unravelling of their underlying molecular mechanisms. The use of assays dedicated
to the analysis of cell adhesion and migration in vitro also affords an efficient way of conducting larger basic and applied
research screenings of the conditions affecting these processes and are potentially exploitable in the context of routine
tests in the biological and medical fields. Therefore, there is a substantial interest in devicing more rationale such assays
and major contributions in this direction have been provided by the advent of procedures based on fluorescent cell tagging.
In this article we describe three fluorescence-based model assays for the qualitative and quantitative assessment of cell
adhesion and cell locomotion in static and dynamic conditions. The assays are easily performed, accurate and reproducible,
and can be automatized for high-throughput screenings of cell behavior in vitro. Performance of the assays involves the use
of certain dedicated disposable accessories, which are commercially available, and a few instruments that, due to their versatility,
can be regarded as constituents of a more generic laboratory setup. 相似文献
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The seedlings of twenty eight annual and perennial desert plants belonging to fifteen families were raised under controlled growth conditions and subjected to a range of tests. The water use efficiency, photosynthesis, extreme temperatures and drought tolerance were monitored. The results were discussed for their ecological significance as a basic information to applied research. Seedlings which were more tolerant to extreme high and low temperatures and drought were more capable of controlling water loss through better water use efficiency. At temperatures below 25°C, the annual plants had higher photosynthetic rate than perennials, whereas at higher temperatures, the perennials were advantaged. 相似文献
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A comparative map of the porcine and human genomes demonstrates ZOO-FISH and gene mapping-based chromosomal homologies 总被引:2,自引:2,他引:0
ZOO-FISH with chromosome-specific DNA libraries (CSLs) from individual flow-sorted human chromosomes was applied on porcine
metaphase chromosomes to establish segment homology between the pig and human karyotypes. Forty-seven porcine chromosomal
segments corresponding to all human chromosomes except the Y were delineated, resulting in a nearly complete coverage of the
porcine karyotype. The syntenic segments detected were further confirmed by the gene mapping information available in the
two species. A map demarcating physical boundaries of human homologies on individual pig chromosomes is complemented with
a detail survey of the physical and genetic linkage mapping data in the two species. The resultant map, thus, provides a comprehensive
and updated comparative status of the human and porcine genomes.
Received: 9 September 1995 / Accepted: 4 December 1995 相似文献