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排序方式: 共有1416条查询结果,搜索用时 15 毫秒
921.
This paper, the first of a two-part series, aims to find the effect of stitch length, check spring tension, fabric feed timing and needle thread in-take length on tension peaks occurring on a spun polyester needle thread during a sewing cycle of a SNLS sewing machine. The pre-tensions on the bobbin and needle threads and sewing speed were kept constant. A PC interfaced measuring instrument was fabricated to measure dynamic sewing tension on needle thread above the needle bar. Four prominent tension peaks were detected. Longer stitch length causes higher tension peaks; and shorter length stitch requires higher pre-tension to obtain a balanced stitch. The check spring tension has no effect on tightening tension. Incorrect timing of feed dog can cause very high tightening tension. The change in the position of thread length guide alters the friction of needle thread at critical guides which determines the length of thread to be released through tensioner; release of longer length of thread results in lower tension peaks (1, 2 and 4) and vice versa. 相似文献
922.
Ah Young Park Imane Nafia Damien N. Stringer Samuel S. Karpiniec J. Helen Fitton 《Marine drugs》2022,20(1)
Fucoidan compounds may increase immune activity and are known to have cancer inhibitory effects in vitro and in vivo. In this study, we aimed to investigate the effect of fucoidan compounds on ex vivo human peripheral blood mononuclear cells (PBMCs), and to determine their cancer cell killing activity both solely, and in combination with an immune-checkpoint inhibitor drug, Nivolumab. Proliferation of PBMCs and interferon gamma (IFNγ) release were assessed in the presence of fucoidan compounds extracted from Fucus vesiculosus, Undaria pinnatifida and Macrocystis pyrifera. Total cell numbers and cell killing activity were assessed using a hormone resistant prostate cancer cell line, PC3. All fucoidan compounds activated PBMCs, and increased the effects of Nivolumab. All fucoidan compounds had significant direct cytostatic effects on PC3 cells, reducing cancer cell numbers, and PBMCs exhibited cell killing activity as measured by apoptosis. However, there was no fucoidan mediated increase in the cell killing activity. In conclusion, fucoidan compounds promoted proliferation and activity of PBMCs and added to the effects of Nivolumab. Fucoidan compounds all had a direct cytostatic effect on PC3 cells, as shown through their proliferation reduction, while their killing was not increased. 相似文献
923.
924.
Alves Tainá S. Alvarado Fredy Arroyo-Rodríguez Víctor Santos Bráulio A. 《Landscape Ecology》2020,35(7):1619-1633
Landscape Ecology - The role of protected areas as biodiversity repositories has become increasingly important in face of increased deforestation. By adding free-living exotic mammals, removing... 相似文献
925.
Habitat use by two extremophile,highly endemic,and critically endangered fish species (Gambusia eurystoma and Poecilia sulphuraria; Poeciliidae) 下载免费PDF全文
Zachary W. Culumber Garrett W. Hopper Nicholas Barts Courtney N. Passow Samuel Morgan Anthony Brown Lenin Arias‐Rodriguez Michael Tobler 《水产资源保护:海洋与淡水生态系统》2016,26(6):1155-1167
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926.
Mikasová E Drahovská H Szemes T Kuchta T Karpísková R Sásik M Turna J 《Veterinary microbiology》2005,109(1-2):113-120
Twenty-eight strains of Salmonella enterica serovar Typhimurium were characterized by three PCR-based methods. Ten strains harbored type I integrons and two different integron profiles were detected. Typing by amplified fragment length polymorphism (AFLP) resulted in observation of 10 profiles that differed by one to six bands. Salmonella strains were screened for presence of phage genes using a PCR-phage typing; five genes from P22 phage and genes encoding putative virulence factors from phages Gifsy-1, Gifsy-2 and Fels-1 were selected for testing. This set of genes was sufficient for dividing the strains into eight different PCR-phage profiles. Similar grouping of strains was observed in case of all the employed DNA techniques and they corresponded well with the phage type and antimicrobial resistance of the strains. The highest discriminating power was achieved with use of the AFLP, yet the detection of integrons and PCR-phage typing also proved to be valuable in typing the S. Typhimurium strains. 相似文献
927.
928.
Celerá V Carasová P 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2002,49(3):155-159
Three oligonucleotide primers for semi-nested polymerase chain reaction (PCR) were designed according to already published sequences of porcine circovirus types 1 (PCV-1) and 2 (PCV-2) isolates. These primers were used to detect PCV-2 DNA. A positive amplification reaction was visualized from a DNA suspension containing as few as 10 copies of virus DNA. In total. 77 samples of inguinal lymph nodes and nasal swabs from pigs in the Czech Republic were used to detect the virus. Thirty-seven of them were positive for PCV-2 DNA. In order to confirm specificity of the PCR reaction, seven DNA fragments were sequenced. Czech PCV sequences were found to have a 92-97% homology with other known PCV-2 strains and only 80-83% homology with PCV-1 strains. 相似文献
929.
In this paper we examine how internal migration redistributes earned income across U.S. states between 1995 and 2010. We examine interregional income flows by first describing the movement of earned income between U.S. states. Second, we examine the effect of income migration on spatial patterns of income inequality. The question we ask is, “does migration increase or decrease convergence income across U.S. States?” A primary contribution of this paper is that instead of using only 1 year of income migration data to explore these issues, we use yearly data from the first year the Internal Revenue Service (IRS) data started including income (1995/1996) up to the most current data available (2009/2010). Results indicate that income convergence/divergence across states varies by whether or not there is general economic expansion or contraction. Nevertheless, some high‐amenity states continually attract high‐income households. 相似文献
930.
The ratio of monounsaturated oleic fatty acid to polyunsaturated linoleic fatty acid (O/L) and the associated agronomic traits
were profiled for local peanut (Arachis hypogaea L.) cultivars and accessions in Botswana. The research was tested on 16 entries planted in four localities across the country.
The average total oil yield of the genotypes studied was about 42.1% and there was no significant difference in total oil
yield (P < 0.05) across the four research sites and among all entries (accessions). The average mean O/L ratio for all entries was
about 1.47. The highest was that of the locally improved variety, Peolwane (2.58), which was significantly different (P < 0.05) from all other accessions, and the lowest is that of the local accession GO 63 (1.23). This study also profiled the
agronomic yield traits to identify genotypes that have both high oil quality and high yielding potential. No correlation was
detected between pod yield and O/L ratio among the tested genotypes. The station with little rainfall but adequate repartition
showed a very high O/L ratio for some genotypes, and future work is recommended to test this interesting observation on the
correlation between moisture stress and oil quality. 相似文献