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排序方式: 共有350条查询结果,搜索用时 31 毫秒
101.
de Paleville DT Topp RV Swank AM 《Journal of strength and conditioning research / National Strength & Conditioning Association》2007,21(2):635-637
Treatment for breast cancer patients includes surgical removal of the tumor followed by chemotherapy. Chemotherapy frequently results in difficult to manage symptoms that threaten compliance with the therapy. Symptoms include fatigue, declines in functional ability, muscle wasting, and a decreased quality of life. Preparing the body to tolerate a stressful event such as chemotherapy has been termed "prehabilitation". This case study determined the efficacy of introducing aerobic training 1 week prior to and continuing through 8 weeks of chemotherapy on fatigue and functional ability in a 42-year-old newly diagnosed breast cancer patient. The patient participated in a supervised and home-based walking program. Fatigue during daily activities and functional ability (12-minute walk, ascending and descending stairs, sit to stand, getting to and rising from the floor, 30-second bicep curl) were measured before and after exercise training. Results indicate that 5 of 7 functional measures demonstrated improvement, ranging from 23.4- 54.5%. In addition, fatigue while performing activities of daily living, as well as following the performance of the functional tasks, was reduced. The findings of this case study indicate that fatigue can be decreased and functional ability can be improved as a result of aerobic training initiated 1 week before and continued throughout chemotherapy. This case study presents a novel approach to introducing exercise prior to and continued during 8 weeks of chemotherapy in a way that may reduce the cumulative effects of this stressor. 相似文献
102.
以宁夏盐池县荒漠草原人工柠条(Caragana intermedia)林为研究对象,分别选取柠条林冠下东侧(SE),冠下西侧(SW)及带间(Gap)为研究样地,从群落水平探讨柠条对冠下草本植物群落结构、物种多样性及功能群分布的影响。结果表明:(1)在3种微生境中均鉴定出12种植物,SW以蒙古冰草为优势种,SE以蒙古冰草和中亚白草为优势种,Gap则以蒙古冰草和牛枝子为优势种。(2)与Gap相比,SW和SE植物群落的平均高度分别增加了41.06%和81.75%,地上生物量分别增加了40.88%和38.73%。SW和SE中,禾本科植物地上生物量分别占地上总生物量的67.10%和58.40%,显著高于Gap (P<0.05)。(3)柠条冠层效应使得草本植物的物种丰富度指数增加,但Shannon-Winner指数、Simpson指数和Pielou指数显著差异(P>0.05),变化范围分别为1.620-1.756、0.701-0.730和0.775-0.878。(4)冗余分析表明:土壤温度、空气相对湿度及土壤有机碳是影响草本植物物种多样性及生物量的主要因子,解释量分别为42.70%,11.70%和8.80%。研究表明,柠条对冠下草本植物群落尤其是禾本科植物具有一定的保育作用,该效应的产生主要是由于柠条冠下微气候及土壤环境因子的改善为草本植物的生长发育提供了有利条件。柠条对草本植物的保育作用对荒漠草原生态环境的保护与恢复具有重要意义。 相似文献
103.
目的 探究生防细菌DS-R5施入丹参植株后根际和根表土壤细菌群落组成及多样性变化。方法 向丹参植株根部施入生防细菌DS-R5,以未施用细菌为对照组,分别采集根际和根表土壤样品提取总DNA,扩增样品总DNA的V3-V4区,采用Illumina MiSeq测序平台对PCR扩增产物进行双端测序分析,利用生物信息学分析解析丹参植株根际土壤和根表土壤细菌群落结构组成及多样性。结果 菌株DS-R5处理后增加了根际土壤细菌群落的多样性和丰度,降低了根表土壤细菌群落的多样性和丰度;高通量测序得到的根际和根表土壤的有效序列数量和OTU数量相比对照组均有所下降,根际土壤处理样品中微生物种类最丰富,根表土壤处理样品中微生物种类最少,根际土壤处理样品与根际土壤对照物种种类更接近;在门水平上,根际土壤处理样品相比对照变形菌门丰度下降,酸杆菌门丰度升高,根表土壤处理样品相比对照变形菌门和酸杆菌门丰度均升高,放线菌门丰度降低;在属水平上,根际土壤处理样品中鞘氨醇单胞菌属、芽胞杆菌属、慢生根瘤菌属相比根际土壤对照占比均有升高,根表土壤处理样品相比对照黄杆菌属和伯克菌属丰度下降,而土壤中的优势菌属根瘤菌属和芽胞杆菌属丰度升高。结论 丹参植株施用生防细菌DS-R5后,改变了根际土壤和根表土壤中微生物群落结构和多样性。 相似文献
104.
Michelle Sait Morag Livingstone Ewan M Clark Nick Wheelhouse Lucy Spalding Bryan Markey Simone Magnino Frederick A Lainson Garry SA Myers David Longbottom 《BMC genomics》2014,15(1)
Background
Chlamydia pecorum is the causative agent of a number of acute diseases, but most often causes persistent, subclinical infection in ruminants, swine and birds. In this study, the genome sequences of three C. pecorum strains isolated from the faeces of a sheep with inapparent enteric infection (strain W73), from the synovial fluid of a sheep with polyarthritis (strain P787) and from a cervical swab taken from a cow with metritis (strain PV3056/3) were determined using Illumina/Solexa and Roche 454 genome sequencing.Results
Gene order and synteny was almost identical between C. pecorum strains and C. psittaci. Differences between C. pecorum and other chlamydiae occurred at a number of loci, including the plasticity zone, which contained a MAC/perforin domain protein, two copies of a >3400 amino acid putative cytotoxin gene and four (PV3056/3) or five (P787 and W73) genes encoding phospholipase D. Chlamydia pecorum contains an almost intact tryptophan biosynthesis operon encoding trpABCDFR and has the ability to sequester kynurenine from its host, however it lacks the genes folA, folKP and folB required for folate metabolism found in other chlamydiae. A total of 15 polymorphic membrane proteins were identified, belonging to six pmp families. Strains possess an intact type III secretion system composed of 18 structural genes and accessory proteins, however a number of putative inc effector proteins widely distributed in chlamydiae are absent from C. pecorum. Two genes encoding the hypothetical protein ORF663 and IncA contain variable numbers of repeat sequences that could be associated with persistence of infection.Conclusions
Genome sequencing of three C. pecorum strains, originating from animals with different disease manifestations, has identified differences in ORF663 and pseudogene content between strains and has identified genes and metabolic traits that may influence intracellular survival, pathogenicity and evasion of the host immune system.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-23) contains supplementary material, which is available to authorized users. 相似文献105.
目的:改进现有的细胞冷冻保存方法,建立一个不含二甲基亚砜(DMSO)和血清(FBS)的高效冷冻保存方法,为细胞治疗等临床实践提供优质细胞.方法:海藻酸微囊包埋鼠胚成纤维细胞(STO细胞)后用不含DMSO和FBS的冷冻保存液进行冷冻保存.设四个对照组:添加10%DMSO和20%FBS的组、仅添加10%DMSO的组、仅添加20%FBS、DMSO和FBS均不添加组.在冷冻前后对各实验组细胞用台盼兰染色,进行细胞计数,计算细胞存活率,同时利用溴乙锭的二聚物(EthD)、钙黄绿素-AM(Calcein-AM)进行染色观察细胞的形态,且进一步验证细胞存活率;解冻复苏后用MTT法评估细胞的增殖速度和生长活力.结果:冷冻保存30天后对各组的细胞数量、细胞存活率、细胞形态和解冻复苏后细胞的生长活力进行比较发现,海藻酸微囊包埋冷冻组的细胞数、细胞存活率、细胞形态和生长活力均与添加DMSO和FBS的组之间无显著性差异,而与其它三个对照组呈显著性差异.结论:使用海藻酸微囊替代DMSO和FBS保存STO细胞,能有效的维持细胞形态、数量、存活率,同时不影响细胞的生长活力,从而建立了一个不含DMSO和FBS的高效冷冻保存方法. 相似文献
106.
The arrangement of simian virus 40 sequences in the DNA of transformed cells. 总被引:156,自引:0,他引:156
High molecular weight DNA, isolated from eleven cloned lines of rat cells independently transformed by SV40, was cleaved with various restriction endonucleases. The DNA was fractionated by electrophoresis through agarose gels, denatured in situ, transferred directly to sheets of nitrocellulose as described by Southern (1975), and hybridized to SV40 DNA labeled in vitro to high specific activity. The location of viral sequences among the fragments of transformed cell DNA was determined by autoradiography. The DNAs of seven of the cell lines contained viral sequences in fragments of many different sizes. The remaining four cell lines each contain a single insertion of viral DNA at a different chromosomal location. The junctions between viral and cellular sequences map at different places on the viral genome. 相似文献
107.
Diversity and Distribution of Commensal Fecal Escherichia coli Bacteria in Beef Cattle Administered Selected Subtherapeutic Antimicrobials in a Feedlot Setting 总被引:1,自引:0,他引:1
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Ranjana Sharma Krysty Munns Trevor Alexander Toby Entz Parasto Mirzaagha L. Jay Yanke Michael Mulvey Edward Topp Tim McAllister 《Applied microbiology》2008,74(20):6178-6186
Escherichia coli strains isolated from fecal samples were screened to examine changes in phenotypic and genotypic characteristics including antimicrobial susceptibility, clonal type, and carriage of resistance determinants. The goal of this 197-day study was to investigate the influence of administration of chlortetracycline alone (T) or in combination with sulfamethazine (TS) on the development of resistance, dissemination of defined strain types, and prevalence of resistance determinants in feedlot cattle. Inherent tetracycline resistance was detected in cattle with no prior antimicrobial exposure. Antimicrobial administration was not found to be essential for the maintenance of inherently ampicillin-resistant and tetracycline-resistant (Tetr) E. coli in control animals; however, higher Tetr E. coli shedding was observed in animals subjected to the two treatments. At day 0, high tetracycline (26.7%), lower sulfamethoxazole-tetracycline (19.2%), and several other resistances were detected, which by the finishing phase (day 197) were restricted to ampicillin-tetracycline (47.5%), tetracycline (31.7%), and ampicillin-tetracycline-sulfamethoxazole (20.8%) from both treated and untreated cattle. Among the determinants, blaTEM1, tet(A), and sul2 were prevalent at days 0 and 197. Further, E. coli from day 0 showed diverse antibiogram profiles and strain types, which by the finishing phase were limited to up to three, irrespective of the treatment. Some genetically identical strains expressed different phenotypes and harbored diverse determinants, indicating that mobile genetic elements contribute to resistance dissemination. This was supported by an increased linked inheritance of ampicillin and tetracycline resistance genes and prevalence of specific strains at day 197. Animals in the cohort shed increasingly similar genotypes by the finishing phase due to animal-to-animal strain transmission. Thus, characterizing inherent resistance and propagation of cohort-specific strains is crucial for determining antimicrobial resistance in cattle. 相似文献
108.
H-FABP基因的多态性和营养因素对猪肉质的影响 总被引:4,自引:0,他引:4
遗传和营养因素都能影响猪肉的品质。但是, 到目前为止同时研究遗传和营养因素对肉质影响的报道很少。在本研究中, 136头PIC5系杂交猪, 体重65 kg, 被随机分成4组, 各组分别给予不同日粮。在饲养35 d、体重大约90 kg时统一屠宰并且进行肉质测定、H-FABP基因分型及其与肉质性状的关联分析。结果表明: (1)所采用的3种日粮对肉色、屠宰后24 h的pH、肌内脂肪和肌肉蛋白含量有极显著的影响; (2)H-FABP基因型对肌内脂肪和肌肉蛋白含量存在极显著的影响; (3)H-FABP基因多态性和营养因素的交互作用对pH 和肌内脂肪含量均有显著的影响, 对照组的AA基因型具有最高pH值, 高维生素E组的AA基因型具有最高肌内脂肪值。实验结果提示在关于猪肉质的育种和生产过程中应该同时考虑营养因素和遗传因素。 相似文献
109.
110.