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101.
K Yang M Fraser M Yu M Krkosek JR Challis GE Lamming LE Campbell A Darnel 《Canadian Metallurgical Quarterly》1996,55(6):1231-1236
The present study was designed to examine the pattern and cellular localization of 11 beta-hydroxysteroid dehydrogenase type 1 (11 beta-HSD1) gene expression in the ovine uterus during pregnancy and at 3 mo postpartum. High levels of 11 beta-HSD1 mRNA were detected in the endometrium from Days 60 to 143 (term = 145 days), and the levels did not change significantly during that time. The level of 11 beta-HSD1 mRNA in the endometrium was always much higher than that in the myometrium, in which the mRNA was not readily detectable throughout pregnancy; at 3 mo postpartum, 11 beta-HSD1 mRNA became undetectable in both endometrium and myometrium. Within the endometrium, intense immunoreactive 11 beta-HSD1 was localized exclusively to the luminal epithelium, and the intensity of 11 beta-HSD1 immunostaining closely followed the level of 11 beta-HSD1 mRNA. To determine whether the level of endometrial 11 beta-HSD1 mRNA was related to the status of ovarian function, tissues from non-pregnant animals at different stages of their reproductive cycle were also examined. It was found that 11 beta-HSD1 mRNA was undetectable in the endometrium of cycling animals up to Day 9 of the estrous cycle but was detectable thereafter. Taken together, these results demonstrate that within the ovine uterus the endometrium is always the dominant site of 11 beta-HSD1 gene expression in relation to the myometrium. Furthermore, the expression of 11 beta-HSD1 mRNA in the endometrium is closely related to the status of the reproductive cycle. The mRNA for 11 beta-HSD1 is highly expressed only during pregnancy and in non-pregnant animals during the late luteal phase. Since circulating levels of progesterone are elevated during both of these periods, the present findings suggest a progesterone effect on uterine 11 beta-HSD1 gene expression. 相似文献
102.
RD Fraser 《Canadian Metallurgical Quarterly》1996,55(4):217-220
Rheumatoid arthritis is described by Swanson (1995) as 'the greatest crippler from the standpoint of severity and prolonged disability' (p. 1307). One key factor in keeping persons with rheumatoid arthritis independent in their activities of daily living is maintaining functional use of their hands. In rural areas, where a move to assisted accommodation may require a person to leave the locality, this splint may help older citizens to remain functional and at home. The deformity and instability caused in rheumatoid arthritic hands by radial deviation of the wrist and subsequent ulnar deviation of the metacarpophalangeal (MCP) joints can greatly affect functional use of the hands. In this article, design and fabrication instructions for a lycra working splint which is suitable for the rheumatoid arthritic hand with MCP ulnar deviation are presented. Health professionals working in rural areas will find this splint inexpensive and easy to design, either alone or, ideally, with the assistance of regional occupational therapists. 相似文献
103.
104.
A. V. Murthy G. T. Fraser D. P. DeWitt 《Journal of research of the National Institute of Standards and Technology》2005,110(2):97-100
This paper presents a statistical evaluation of the responsivity data on a number of heat-flux sensors, calibrated using an electrical substitution radiometer as a transfer standard up to 5 W·cm−2. The sensors, furnished by the customers, were of circular-foil or thermopile type. Comparison of the NIST and the customer measured responsivity values showed that the measurements agree within 3 % for more than half the number of sensors tested, so far. Considering the variation in the customer calibration techniques and the wide measuring range of the sensors used in the calibration, the agreement is encouraging. 相似文献
105.
106.
Murali V. Wu A.T. Chatterjee A.K. Fraser D.B. 《Semiconductor Manufacturing, IEEE Transactions on》1992,5(3):214-222
The use of a simple, rapid and nondestructive technique for inline monitoring of electrically active impurities introduced during wafer fabrication is reported. This AC surface photovoltage-based technique can determine the substrate doping type, doping concentration, oxide charge, and energy distribution of interface traps on both bare and oxidized silicon wafers without the formation of gate electrodes and substrate contacts. The technique is shown to have good reproducibility and resolution for quantifying the electrically active impurities, on the order of 1×1010 q/cm2. Detection of contaminants and static charges by this technique is shown to correlate well with the electrical performance of thin dielectrics. The use of this technique for inline monitoring of very low levels of plasma-induced damage in the SiO2/Si system is also discussed as is the potential for this tool in reducing furnace downtimes and in prompt identification of the source of contamination 相似文献
107.
108.
PA Huber Y Gao ID Fraser O Copeland M EL-Mezgueldi DA Slatter NE Keane SB Marston BA Levine 《Canadian Metallurgical Quarterly》1998,37(8):2314-2326
We have used isotope-edited nuclear magnetic resonance spectroscopy, binding studies, and ATPase activity assays to investigate the interaction with F-actin of the 10 kDa C-terminal 658C fragment of chicken gizzard caldesmon and two site-directed mutants of this fragment. Simultaneous dual-sited contacts with F-actin are observed for the segments of the 658C sequence flanking tryptophan residues 692 and 722. Competition experiments showed that both 658C contacts with actin are displaced by substoichiometric concentrations of the short inhibitory region of troponin-I indicative of different binding sites on actin for these regions of troponin-I and caldesmon. Substitution of caldesmon serine-702 by aspartic acid within the spacer region linking the two actin contacts of 658C led to weaker binding but with retention of equivalent affinity for each interaction site. Differential binding affinity of the two sites was achieved by replacement of the sequence Glu691-Trp-Leu-Thr-Lys-Thr696 by Pro-Gly-His-Tyr-Asn-Asn. Consistent with these data, the concentration of this Cg1 mutant required to achieve 50% inhibition of actin-tropomyosin-activated myosin ATPase was 4-fold greater than found for the 658C fragment. Although calmodulin binding to Cg1 was observed, calmodulin proved ineffective in relieving the inhibition induced by the binding of this mutant to actin. These results are discussed in light of the actin contacts which are involved in the inhibitory activity possessed by different regions of the C-terminus of caldesmon. 相似文献
109.
M Jeffrey CM Goodsir A Holliman RJ Higgins ME Bruce PA McBride JR Fraser 《Canadian Metallurgical Quarterly》1998,142(20):534-537
Brains from 17 histopathologically confirmed cases of scrapie, five of which had congophilic vascular amyloid, were stained immunohistochemically for prion protein (PrP) using a polyclonal antibody. Two clinically suspect but pathologically unconfirmed cases of natural sheep scrapie and the brains of four mice infected with the 111A murine scrapie strain were also examined. Selected sections containing amyloid were stained with each of two peptide antibodies which recognise the N-terminal amino acid residues which are lost following protease digestion of the disease-specific isoform of PrP. The mice infected with the 111A murine scrapie strain had large numbers of hypermature plaques. All the amyloid plaques from both natural sheep scrapie brains and experimental murine brains were heavily immunostained by the polyclonal and both peptide antibodies. In addition, disease-specific accumulations of PrP were detected in endothelial cells or in the intima of blood vessels of the cerebral cortex of sheep scrapie brains. The affected blood vessels were located in areas which otherwise lacked typical scrapie pathology. Vascular accumulations of PrP were also found in leptomeningeal and choroid plexus blood vessels. Vascular amyloid was found mainly in the neocortex. Vascular amyloid and disease-specific parenchymal accumulations of PrP were found in two sheep which showed clinical signs of scrapie but lacked its typical vacuolar pathology. These results show that the mature amyloid of scrapie is composed of, or contains a substantial proportion of, whole length PrP protein. Thus truncation of PrP is not essential for the aggregation of PrP into amyloid. The vascular amyloid of natural sheep scrapie originates from the accumulation and release of PrP from endothelial cells presumably following systemic scrapie infection. The topography of vascular amyloid distribution in Great Britain differs from that reported in the Netherlands. As amyloid deposition in mice is largely controlled by the strain of the infecting agent it is possible that the strain of the agent may influence vascular amyloid deposition. 相似文献
110.
Emerging peephole optimizers can relieve code generators of much case analysis, but delaying code generation decisions requires register allocation algorithms that accept object code instead of the more usual intermediate code. This paper describes two programs that implement such algorithms for a retargetable optimizing compiler. In a machine-independent fashion, they allocate and assign registers, eliminate common subexpressions (including often-missed machine-specific ones), identify dead variables, and define windows for the companion peephole optimizer. Their techniques for handling machine-specific data should generalize to other optimizations as well. 相似文献