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101.
CJ Gore SC Little AG Hahn GC Scroop KI Norton PC Bourdon SM Woolford JD Buckley T Stanef DP Campbell DB Watson DL Emonson 《Canadian Metallurgical Quarterly》1997,75(2):136-143
Patients with craniocervical mandibular (TMD) disorders can present with tinnitus as a primary or secondary complaint. The embryology and functional anatomy of the middle ear, temporomandibular joint, muscles of mastication and associated tendons, ligaments, blood vessels, nerves and lymphatics was found to be helpful in establishing etiologic concepts which relate tinnitus to these temporomandibular disorders. In addition to etiologic concepts, treatment modalities are described. The authors relate their experiences as well as those of others with different patient populations. 相似文献
102.
C.W. Morton D.J. Wills K. Stjernberg 《International Journal of Refractory Metals and Hard Materials》2005,23(4-6):287-293
In order to more effectively control the WC grain growth during liquid phase sintering of submicron WC–Co alloys, the temperature ranges where common grain growth inhibitors are most active have been determined. In the study, small additions (0.5% by weight) of TiC, TaC, NbC, VC, and Cr3C2 were added to WC–6Co and WC–10Co alloys. In some cases, a small amount of coarse WC powder was added to simulate the effect of discontinuous grain growth. The powder compacts were vacuum sintered at temperatures ranging from 1300 to 1575 °C. The magnetic coercivity and microstructure results indicated that VC is equally effective in limiting continuous grain growth for all temperatures within the temperature range while the other inhibitors become more effective with temperature. VC was also found to be the most effective inhibitor of discontinuous grain growth. The results of the investigation are expressed in terms of the effectiveness of grain growth inhibition as determined by microstructural analysis, magnetic coercivity and hardness. 相似文献
103.
Although body condition score was not significantly different between light (<55 kg, n = 6) and heavy (> or =60 kg, n = 7) ewes at mating, it declined between Day 30 and Day 90 of gestation in light but not heavy ewes, and remained lower up to term. All ewes bore twins, delivered near term (Days 144-146) by Caesarean section. One lamb was immediately placed into a warm (30 degrees C; WD) and its twin into a cool (15 degrees C; CD) ambient temperature, and tissues were sampled at 0.5 h or 6 h. All CD lambs born to light ewes exhibited hypothermia and/or respiratory failure and did not survive longer than 30 min; these symptoms were not observed in their WD twins or any lamb born to heavy ewes. Total lamb birth weight, placental weight and fetal cotyledonary weight were lower with light than with heavy ewes. Lambs born to light ewes had less perirenal adipose tissue and smaller liver, heart, kidneys, brain, adrenals and thyroid, although their heart, brain and pancreas represented a larger proportion of total bodyweight; pancreas weight was similar to that in lambs born to heavy ewes. Hence, maternal bodyweight critically influences placental weight and lamb size and survival after birth. 相似文献
104.
DP Murdoch DG Armstrong JB Dacus TJ Laughlin CB Morgan LA Lavery 《Canadian Metallurgical Quarterly》1997,36(3):204-8; discussion 256
The purpose of this study is to report the prevalence of reamputation following resection of the great toe and first ray in adults with diabetes. We abstracted the medical records of 90 diabetic great-toe and first-ray amputees admitted between 1981 and 1991. The most common etiologies of initial amputations were ulcer with soft tissue infection (39%), ulcer with osteomyelitis (32%), and puncture wounds (12%). Sixty percent of all patients had a second amputation, 21% had a third, and 7% had a fourth. Fifteen percent of the patients who had a second amputation had it contralaterally. Seventeen percent subsequently underwent a below-knee amputation and 11% had a Transmetatarsal amputation on the same extremity, 3% had a below-knee amputation, and 2% a transmetatarsal amputation contralaterally. The mean time from the first to the second amputation was approximately 10 months. The results of this study suggest that a large proportion of patients undergoing an amputation at the level of the great toe or first ray have subsequent amputations in the first year following the initial procedure. Additionally, it appears that the contralateral foot may be at significant risk for distal amputation following resection of the hallux or first day. 相似文献
105.
Using two separate methods, we have determined that all six potential sites for N-linked glycosylation on the rat lutropin/choriogonadotropin receptor (rLHR) contain carbohydrates. The functional roles of the carbohydrates were analyzed initially through the use of two nonglycosylated receptor mutants rLHR(N(77,152,173,269,277,291)Q) and rLHR(N(77,152,269,277,291)Q;T(175)A). Although Western blot analyses demonstrated both mutant receptors to be stably expressed, little or no hCG binding activity could be detected in detergent solubilized extracts of 293 cells expressing either nonglycosylated LHR mutant. Although this loss of hCG binding was concluded to be due to misfolding, it was unknown whether this misfolding was due to the absence of carbohydrates or to the multiple amino acid substitutions that had been introduced into the polypeptide. To differentiate between these possibilities, hCG binding assays were performed with nonglycosylated receptors obtained after tunicamycin treatment of cells expressing the wild-type rLHR. Even though these wild-type receptors were confirmed to be devoid of all N-linked carbohydrates by Western blots, they were found to bind hCG with a normal high affinity. In addition, tunicamycin-derived, nonglycosylated LHRs were present at the cell surface and exhibited a phenotype consistent with mature receptors due to their capability to mediate hCG-stimulated cAMP production as well as bind oLH with high affinity. These results indicate that the loss of high affinity hormone binding by rLHR(N(77,152,173,269,277,291)Q) and rLHR(N(77,152,269,277,291)Q;T(175)A) is simply due to the collective amino acid substitutions rather than to the absence of carbohydrates. Therefore, N-linked carbohydrates are not absolutely required for the proper folding of the rLHR into a mature receptor capable of binding hormone and signaling. These results are in marked contrast to the follitropin receptor (FSHR), a very similar receptor which has been shown to strictly require N-linked carbohydrates for folding of the nascent protein. 相似文献
106.
107.
Analysis of exempt paint solvents by gas chromatography using solid-phase microextraction 总被引:1,自引:0,他引:1
Rosemarie R. Bodrian Albert C. Censullo Dane R. Jones Mark J. Rashkin Max T. Wills 《Journal of Coatings Technology》2000,72(900):69-74
Acetone, methyl acetate, and parachlorobenzotrifluoride (PCBTF or Oxsol? 100) have been exempted as VOC solvents by the U.S.
Environmental Protection Agency. In measuring coating VOC content, separate methods for determining exempt solvents are required.
One such method utilizes solid-phase microextraction (SPME) to sample the headspace of solvent-based coatings to which the
surrogates acetone-d6, methyl acetate-d3, and/or metachlorobenzotrifluoride have been added. The sampled exempt coating solvents
are thermally desorbed and analyzed using gas chromatography with flame ionization or mass spectral detection. The SPME headspace
method has also been used to analyze MEK, butyl acetate, tert-butyl acetate, toluene, and xylene in solventborne coatings,
and alcohols in waterborne systems. This paper presents the results obtained for acetone and toluene in a large number of
aerosol paints. Additionally, the results from a round-robin study for acetone, methyl acetate, and parachlorobenzotrifluoride
in commercial solvent-based coatings are reported. 相似文献
108.
109.
Holmbeck Grayson N.; Johnson Sharon Z.; Wills Karen E.; McKernon Wendy; Rose Brigid; Erklin Shannon; Kemper Therese 《Canadian Metallurgical Quarterly》2002,70(1):96
The purpose of this study was to test a mediational model of associations between parental overprotectiveness (OP), behavioral autonomy, and psychosocial adjustment in 68 families with 8- and 9-year-old preadolescents with spina bifida and a demographically matched sample of 68 families with able-bodied children. Measures included questionnaire and observational assessments of parental OP; parent and child reports of behavioral autonomy; and parent, child, and teacher reports of preadolescent adjustment. On the basis of both questionnaire and observational measures of OP, mothers and fathers of children with spina bifida were significantly more overprotective than their counterparts in the able-bodied sample, although this group difference was partially mediated by children's cognitive ability. Both questionnaire and observational measures of parental OP were associated with lower levels of preadolescent decision-making autonomy as well as with parents being less willing to grant autonomy to their offspring in the future. For the questionnaire measure of OP, and only for the spina bifida sample, the mediational model was supported such that parental OP was associated with less behavioral autonomy, which was, in turn, associated with more externalizing problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
110.
A small commercially available laboratory mill was found to be suitable to dehull small batches of sorghum grain. The device used one grinding plate and an agitating dimpled plate and took about 1 min to adequately dehull the grain. At the completion of dehulling period decorticated grain was collected directly in a sample holder. Data from various cultivars, grain sizes and types of grain were reproducible. It only required 10 s to clear the device between samples. 相似文献