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81.
Oligonucleotide N3'-->P5' phosphoramidates (3'-phosphoramidates) are DNA analogs that are presently under investigation as potential therapeutic agents. These compounds may also hold promise as a diagnostic tool. Here, we describe a rapid method for the analysis of single-stranded RNA fragments utilizing 3'-phosphoramidate oligonucleotides as probes in conjunction with capillary gel electrophoresis (CGE). 3'-Phosphoramidate 9-mers were mixed with complimentary RNA, and CGE was used to monitor duplex formation. Complimentary strands of RNA and 3'-phosphoramidate formed duplexes that gave unique relative mobilities based on an internal standard. The ability of CGE to discriminate between perfect duplexes and duplexes that contain a base mismatch was also investigated. However, the primary focus of this work was to determine CGE's ability to detect the presence of the 3'-phosphoramidates/RNA duplex under routine electrophoretic running conditions. Polyacrylamide gel electrophoresis analysis was utilized to verify duplex formation. 相似文献
82.
83.
J Farrar S Portolano N Willcox A Vincent L Jacobson J Newsom-Davis B Rapoport SM McLachlan 《Canadian Metallurgical Quarterly》1997,9(9):1311-1318
The muscle weakness in myasthenia gravis (MG) is caused by heterogeneous high-affinity IgG autoantibodies to the nicotinic acetylcholine receptor (AChR), a complex ion channel glycoprotein. These antibodies are clearly responsible for reducing AChR numbers at the neuromuscular junction in myasthenia; however, the origins, diversity, specificity and pathogenicity of individual antibodies have not yet been established. We have cloned and characterized four different AChR-specific Fab from an MG patient's thymus by screening an IgG1/kappa gene combinatorial lambda phage library with soluble human AChR labeled with [125I] alpha-bungarotoxin. Unlike most previously cloned human antibodies, all four Fab immunoprecipitated soluble human muscle AChR. Two Fab strongly inhibited binding of mAb to the main immunogenic region on the alpha subunits and one Fab bound to an epitope on the fetal-specific gamma subunit. In sensitivity and fine specificity, these Fab resembled the anti-AChR antibodies found in many MG patients, including the donor. The closest germline counterparts for their heavy chains were in VH families 1, 3 and 4; however, there were many differences consistent with an antigen-driven response of diverse B cell clones. The combinatorial approach holds promise for further analysis of human autoantibodies. 相似文献
84.
Urine osmolality and conductivity as indices of hydration status in athletes in the heat 总被引:1,自引:0,他引:1
PURPOSE: The purpose of this study was to determine a quick and easy method for assessment of day-to-day hydration status in athletes in the heat. METHODS: Measurement of the osmolality of the first urine sample of the day collected after wakening but before breakfast established a standardized collection procedure to allow day-to-day comparisons of individuals. RESULTS: Laboratory measurements established that a difference in osmolality is found when individuals are dehydrated by a moderate extent in comparison with an euhydrated situation: the osmolality of the first morning urine sample of control subjects (N = 11) averaged over 5 d was 675 (+/- 232) mosmol.kg-1 (mean +/- SD). For subjects who were hypohydrated by exercise followed by fluid restriction, morning urine osmolality was 924 (+/- 99) mosmol.kg-1 (P < 0.001, N = 11, averaged over 7 d). Field measurements from 29 athletes undertaking warm weather training indicated that the athletes could, with appropriate feedback, maintain a satisfactory hydration status. Athletes in weight category sports tended to record a higher morning urine osmolality, reflecting their attempts to dehydrate: recorded values were 627 (+/- 186) mosmol.kg-1 (nonweight category sports, N = 8), 775 (+/- 263) mosmol.kg-1 (boxers, N = 15) and 777 (+/- 254) mosmol.kg-1 (wrestlers, N = 6). Results obtained with a hand-held portable conductivity were compared with those from measured osmolality. CONCLUSIONS: The findings suggest that such an instrument could provide athletes with reliable information as to their hydration status from measurement of the first morning urine of the day and therefore provide a quick and easy method for achieving an approximation of hydration status from day-to-day. 相似文献
85.
Contamination of enteral diets may play an essential role in formula tolerance and safety for patients. Contaminated enteral formula commonly support microbiological growth. Commercially sterile liquid formulas received from the manufacturer are required by the Food & Drug Administration (FDA) to be shelf-stable and free from enteric pathogens. This study examined the use of large volume, closed system containers in a typical nursing home. Large volume (1500 mL) containers with unique pierceable caps and piercing spikes were studied to determine their ability to reduce the incidence of microbiological contamination due to their design and ability to decrease handling requirements. This study took place in a room of a typical nursing home. In this clinical setting, 211 containers and administration spike sets were evaluated following a 36-h hangtime. Contamination was virtually nondetectable. Nursing staff in a clinical facility can effectively utilize a large volume, prefilled, ready-to-use feeding system to achieve delivery of noncontaminated product for up to 36 h hangtime. 相似文献
86.
87.
Indoor weight loss of steel, chloride, sulphur compounds and dust deposition rate were determined in six storehouses having different characteristics. Relative humidity and temperature were determined in three storehouses. A model for indoor corrosion of steel depending on time of exposure and deposition of dust, sulphur compounds and chlorides is proposed. Dust deposition plays an important role indoors. The position of the sample has also a significant influence on corrosion. Indoor corrosion aggressivity in Cuban storehouses ranges in classification IC3 and IC4 according to the new ISO proposal of indoor aggressivity.A report about the presence of localized corrosion indoors (filiform like) using a special designed sample is made. 相似文献
88.
J. Colin C. Gonzalez R. Herrera J. A. Juarez-Islas 《Journal of Materials Engineering and Performance》2002,11(5):487-491
This study carried out a characterization of chill-cast NiAl alloys with copper additions, which were added to NiAl, such
that the resulting alloy composition occurred in the β-field of the ternary NiAlCu phase diagram. The alloys were vacuum induction
melted and casted in copper chill molds to produce ingots 0.002 m thick, 0.020 m wide, and 0.050 m long. X-ray diffractometry
(XRD) and transmission electron microscopy (TEM) performed in chill-cast ingots identified mainly the presence of the β-(Ni,Cu)Al
phase. As-cast ingots showed essentially no ductility at room temperature except for the Ni50Al40Cu10 alloy, which showed 1.79% of elongation at room temperature. Ingots with this alloy composition were then heat treated under
a high-purity argon atmosphere at 550 °C (24 h) and cooled either in the furnace or in air, until room temperature was reached.
β-(Ni,Cu)Al and γ′(Ni,Cu)3Al were present in specimens cooled in the furnace and β-(Ni,Cu)Al, γ′(Ni,Cu)3Al plus martensite-(Ni,Cu)Al were present in specimens cooled in air. Thermogravimetric analysis indicated that martensite
transformation was the result of a solid-state reaction with M
s ∼ 470 and M
f ∼ 430 °C. Tensile tests performed on bulk heat-treated ingots showed room-temperature ductility between 3 and 6%, depending
on the cooling media. 相似文献
89.
Kenton O’Hara Gerardo Gonzalez Graeme Penney Abigail Sellen Robert Corish Helena Mentis Andreas Varnavas Antonio Criminisi Mark Rouncefield Neville Dastur Tom Carrell 《Computer Supported Cooperative Work (CSCW)》2014,23(3):299-337
While surgical practices are increasingly reliant on a range of digital imaging technologies, the ability for clinicians to interact and manipulate these digital representations in the operating theatre using traditional touch based interaction devices is constrained by the need to maintain sterility. To overcome these concerns with sterility, a number of researchers are have been developing ways of enabling interaction in the operating theatre using touchless interaction techniques such as gesture and voice to allow clinicians control of the systems. While there have been important technical strides in the area, there has been little in the way of understanding the use of these touchless systems in practice. With this in mind we present a touchless system developed for use during vascular surgery. We deployed the system in the endovascular suite of a large hospital for use in the context of real procedures. We present findings from a study of the system in use focusing on how, with touchless interaction, the visual resources were embedded and made meaningful in the collaborative practices of surgery. In particular we discuss the importance of direct and dynamic control of the images by the clinicians in the context of talk and in the context of other artefact use as well as the work performed by members of the clinical team to make themselves sensable by the system. We discuss the broader implications of these findings for how we think about the design, evaluation and use of these systems. 相似文献
90.
Worldwide, cervical cancer is the second most common cancer in women, after breast cancer. The prevalence of this malignant disease is estimated at 1.4 million cases worldwide, causing about 290,000 deaths and 500,000 new cases per year, of which 80% correspond to women living in developing countries. In this work we propose a family of ordered models for basal cells of the cervix corresponding to different stages ranging from normal cells to the formation of precancerous lesions. We analyse the first member of the family analytically and for the second member we developed a non-standard numerical method in order to extract some biological information. 相似文献