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81.
82.
Liquid‐like Ionic Conduction in Solid Lithium and Sodium Monocarba‐closo‐decaborates near or at Room Temperature 下载免费PDF全文
83.
Objective
Dogs, like humans, experience eye changes with aging: hardening and clouding of the lens and accumulated oxidative damage from UV sunlight. It has been debated whether such changes could be affecting the visual function of dogs. The objective of this study was to determine if autorefractometry could be used to measure visual function in dogs.Animals and Methods
Nine Beagle dogs (ages 1 to 14 years) were examined by a veterinary ophthalmologist and their eyes determined to be free of cataracts. Spherical equivalent refractive error was measured by handheld autorefractor (Welch Allyn SureSight) under both indirect and direct lighting conditions with five measurements per condition, per eye. Measures were repeated on three different days for each dog within six weeks. Nonparametric statistics were used to detect differences among lighting conditions and test days, and between eyes. Spearmen correlation assessed the visual measurement outcomes’ association with age.Results
There was no difference for day-to-day or between-eye measurements. Significantly, the Beagles showed a myopic shift with aging (average spherical equivalent ranged from plano to -3.00 diopters), suggesting that dogs become more near-sighted as they age (r = -0.48 and -0.73 under direct and indirect lights; p<0.05 both). Younger dogs were able to make larger accommodation changes from indirect light to direct light conditions, indicating a more flexible lens (r = -0.50, p<0.05).Conclusions
Although designed for humans, the hand-held autorefractor technique is applicable to dogs and sensitive to light conditions. The age-associated myopic shift could be expected to compromise dogs’ visual functions. 相似文献84.
Hsin-I Tong Wen Kang Philip M. C. Davy Yingli Shi Si Sun Richard C. Allsopp Yuanan Lu 《PloS one》2016,11(4)
The ability of monocytes and monocyte-derived macrophages (MDM) to travel towards chemotactic gradient, traverse tissue barriers, and accumulate precisely at diseased sites makes them attractive candidates as drug carriers and therapeutic gene delivery vehicles targeting the brain, where treatments are often hampered by the blockade of the blood brain barrier (BBB). This study was designed to fully establish an optimized cell-based delivery system using monocytes and MDM, by evaluating their homing efficiency, engraftment potential, as well as carriage and delivery ability to transport nano-scaled particles and exogenous genes into the brain, following the non-invasive intravenous (IV) cell adoptive transfer in an acute neuroinflammation mouse model induced by intracranial injection of Escherichia coli lipopolysaccharides. We demonstrated that freshly isolated monocytes had superior inflamed-brain homing ability over MDM cultured in the presence of macrophage colony stimulating factor. In addition, brain trafficking of IV infused monocytes was positively correlated with the number of adoptive transferred cells, and could be further enhanced by transient disruption of the BBB with IV administration of Mannitol, Bradykinin or Serotonin right before cell infusion. A small portion of transmigrated cells was detected to differentiate into IBA-1 positive cells with microglia morphology in the brain. Finally, with the use of superparamagnetic iron oxide nanoparticles SHP30, the ability of nanoscale agent-carriage monocytes to enter the inflamed brain region was validated. In addition, lentiviral vector DHIV-101 was used to introduce green fluorescent protein (GFP) gene into monocytes, and the exogenous GFP gene was detected in the brain at 48 hours following IV infusion of the transduced monocytes. All together, our study has set up the optimized conditions for the more-in-depth tests and development of monocyte-mediated delivery, and our data supported the notion to use monocytes as a non-invasive cell-based delivery system for the brain. 相似文献
85.
【目的】获得江苏沿海滩涂盐生药用植物中华补血草内生及根际具有1-氨基环丙烷-1-羧酸(ACC)脱氨酶活性的细菌,研究其遗传多样性和潜在促生活性。【方法】从中华补血草和根际土壤分离筛选具有ACC脱氨酶活性的菌株,对其ACC脱氨酶活性定量检测,通过16S r RNA基因序列分析确定菌株系统发育地位。同时研究其固氮、溶磷、产植物生长素吲哚乙酸(IAA)及耐盐能力。【结果】分离筛选获得18株具有ACC脱氨酶活性的内生与根际细菌,定量检测发现其中有13株菌的ACC脱氨酶含量在20 nmolα-KA/(mg Pr·h)以上,有11株菌可以固氮,7株菌能够解磷,9株菌产生IAA。菌株的Na Cl盐耐受范围多数在0–13%之间。16S r RNA基因测序表明,活性菌株分属于7个属,多样性丰富,节杆菌属(Arthrobacter)为优势类群。其中菌株KLBMP 5180为节杆菌属的潜在新种。【结论】江苏沿海滩涂盐生药用植物中华补血草共生环境中具有丰富多样的具ACC脱氨酶活性的菌株,并存在潜在新物种资源,具有进一步研究价值。 相似文献
86.
More than metabolic: Considering the broader paleoepidemiological impact of vitamin D deficiency in bioarchaeology 下载免费PDF全文
Anne Marie E Snoddy Hallie R Buckley Siân E Halcrow 《American journal of physical anthropology》2016,160(2):183-196
Vitamin D deficiency has traditionally been viewed as a metabolic bone disease by bioarchaeologists and considered primarily in terms of the development of specific musculoskeletal changes used for diagnosis in paleopathological research. These skeletal manifestations are usually interpreted as representing general ill‐health. Clinical research shows that vitamin D is also integral to a number of extra‐skeletal physiological processes including immunoregulation, blood pressure homeostasis, cell division, and programmed cell death. Vitamin D deficiency and sub‐clinical insufficiency are thought to be risk factors for infectious and autoimmune diseases, as well as certain cancers and cardiovascular diseases. Epidemiological work indicates that the skeletal manifestations of vitamin D deficiency represent the extreme end of a spectrum of morbidity associated with negative health outcomes, including increased risk for secondary tuberculosis. This article provides a review of clinical research on the extra‐skeletal roles of vitamin D and the pathological consequences of poor vitamin D status. Additionally, it presents an interpretive model for bioarchaeological analyses of rickets and osteomalacia for consideration of the whole‐body impact of poor vitamin D nutriture and possible comorbidities that may have affected the wider population. Am J Phys Anthropol 160:183–196, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
87.
Mitigation of ammonia inhibition by internal dilution in high‐rate anaerobic digestion of food waste leachate and evidences of microbial community response 下载免费PDF全文
88.
Jun Feng Su Sheng Chen Zheng Ting Lin Huang Fang Ma Si Cheng Shao Shao Fei Yang 《Geomicrobiology journal》2016,33(7):586-591
A novel bacterium, strain SZ28, identified as Acinetobacter sp., showed anaerobic denitrification ability using Mn(II) as the electron donor. Nitrate-nitrogen concentration decreased from nearly 16.52–mg L?1 to 4.4–mg L?1, without accumulation of nitrite as an intermediate, with a maximum of 0.063–mg NO3?-N L?1 h?1, reaching a peak of 0.085–mg NO3?-N L?1 h?1 in sodium acetate. The nitrate removal rate reached 0.067–mg NO3?-N L?1 h?1, 0.059–mg NO3?-N L?1 h?1, and 0.078 mg NO3?-N L?1 h?1 using Mn(II), S(II), and Fe(II) as electron donors, respectively. The optimum pH was 6.0, with a removal rate of 0.063–mg NO3?-N L?1 h?1 相似文献
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90.