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151.
Linkage of DFNB1 to non-syndromic neurosensory autosomal-recessive deafness in Mediterranean families 总被引:1,自引:0,他引:1
P Gasparini X Estivill V Volpini A Totaro S Castellvi-Bel N Govea M Mila M Della Monica V Ventruto M De Benedetto P Stanziale L Zelante ES Mansfield L Sandkuijl S Surrey P Fortina 《Canadian Metallurgical Quarterly》1997,5(2):83-88
A study involving the immediate loading of Br?nemark implants in the edentulous mandibles of 10 patients is reported. The design involved the immediate loading of four widely distributed implants with a transitional fixed implant-supported prosthesis at first-stage surgery, avoiding the need for a removable prosthesis. A sufficient number of additional implants are allowed to heal in the conventional manner to provide sufficient support for a definitive fixed prosthesis even if all of the immediately loaded implants fail. Preliminary results have been favorable, with all patients functioning with a fixed implant prosthesis from the day of first-stage surgery. 相似文献
152.
Monica Moldovan C. M. Weyant D. Lynn Johnson K. T. Faber 《Journal of Thermal Spray Technology》2004,13(1):51-56
Tantalum (Ta) oxide, due to its high-temperature capabilities and thermal expansion coefficient similar to silicon nitride,
is a promising candidate for environmental barriers for silicon (Si) nitride-based ceramics. This paper focuses on the development
of plasma-sprayed Ta oxide as an environmental barrier coating for silicon nitride. Using a D-optimal design of experiments,
plasma-spray processing variables were optimized to maximize coating density. The effect of processing variables on coating
thickness was also determined. X-ray diffraction (XRD) was use to ascertain that the as-sprayed coatings were comprised of
α- and β-Ta2O5, but were fully converted to β-Ta2O5 after a 1200 °C heat treatment. Grain growth of the Ta2O5 followed a time dependence of t
0.2 at 1200 °C. 相似文献
153.
McDonagh Annmarie; Friedman Matthew; McHugo Gregory; Ford Julian; Sengupta Anjana; Mueser Kim; Demment Christine Carney; Fournier Debra; Schnurr Paula P.; Descamps Monica 《Canadian Metallurgical Quarterly》2005,73(3):515
The authors conducted a randomized clinical trial of individual psychotherapy for women with posttraumatic stress disorder (PTSD) related to childhood sexual abuse (n = 74), comparing cognitive-behavioral therapy (CBT) with a problem-solving therapy (present-centered therapy; PCT) and to a wait-list (WL). The authors hypothesized that CBT would be more effective than PCT and WL in decreasing PTSD and related symptoms. CBT participants were significantly more likely than PCT participants to no longer meet criteria for a PTSD diagnosis at follow-up assessments. CBT and PCT were superior to WL in decreasing PTSD symptoms and secondary measures. CBT had a significantly greater dropout rate than PCT and WL. Both CBT and PCT were associated with sustained symptom reduction in this sample. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
154.
W. David Nes Monica Lopez Wen Zhou De-an Guo Patrick F. Dowd Robert A. Norton 《Lipids》1997,32(12):1317-1323
Heliothis zea (corn earworm), an insect that fails to synthesize sterols de novo, was reared on an artificial diet treated with 18 different sterol supplements. Larvea did not develop on a sterol-less medium.
Δ5-Sterols with a hydrogen atom, a methylene group, an E-or Z-ethylidene group, or an α- or β-ethyl group (cholesterol, ostreasterol, isofucosterol, fucosterol, sitosterol, and clionasterol,
respectively) at position C-24, and Δ5-sterols doubly substituted in the side chain at C-24 with an α-ethyl group and at C-22 with a double bond (stigmasterol)
supported normal larval growth to late-sixth instar (prepupal: maturity). The major sterol isolated from each of these sterol
treatments was cholesterol, suggesting that H. zea operates a typical 24-dealkylation pathway. The sterol requirement of H. zea could not be met satisfactorily by derivatives of 3β-cholestanol with a 9β, 19-cyclopropyl group, gem dimethyl group at C-4, a Δ5,7-bond or Δ8-bond, or by side-chain modified sterols that possessed a Δ25(27)-24β-ethyl group, Δ23(24)-24-methyl group, or 24-ethyl group, or Δ24(25)-24-methyl or 24-ethyl group. The major sterol recovered from the larvae (albeit developmentally arrested larvae) treated
with a nonutilizable sterol was the test compound. Sterol absorption was related to the degree of sterol utilization. The
most effective sterols absorbed by the insect ranged from 27 to 66 μg per insect, whereas the least effective sterols absorbed
by the insect ranged from 0.6 to 6 μg per insect. Competition experiments using different proportions of cholesterol and 24-dihydrolanosterol
(from 9:1 to 1:9 mixtures) indicated that abnormal development of H. zea may be induced on less than a 1 to 1 mixture of utilizable (cholesterol) to nonutilizable (24-dihydrolanosterol) sterols.
The results demonstrate new structural requirements for sterol utilization and metabolism by insects, particularly with respect
to the position of double bonds in the side chain and functionalization in the nucleus. The novel sterol specificities observed
in this study appear to be associated with the dual role of sterols as membrane inserts (nonmetabolic) and as precursors to
the ecdysteroids (metabolic). 相似文献
155.
Rotimi Williams Braimoh Monica Omolara Mabayoje Christiana Oluwatoyin Amira Babawale Taslim Bello 《Hemodialysis international. International Symposium on Home Hemodialysis》2014,18(1):148-152
Patients with end‐stage kidney disease (ESRD) on maintenance hemodialysis (HD) are usually exposed to large volumes of dialysate, which is separated from patients' blood only by thin membrane of dialyzer. It is therefore essential to frequently monitor the quality of HD water to ensure that it meets the recommended standards. The objective of this study was to evaluate the microbial quality of HD water in Lagos, Nigeria. Four sets of pre‐ and post‐treatment water samples, 20 mL each, were collected from six HD centers in Lagos and tested for microbial contamination using the molten Tryptic soy agar in accordance with Association for Advancement of Medical Instrumentation (AAMI) and European Best Practice Guidelines (EBPG). Pyrogen tests were also conducted on pre‐ and post‐treatment samples using standard technique. Information on water treatment modalities, maintenance practices and quality control measures in each center were obtained using a questionnaire. All centers use treated water for HD purpose. None of the HD centers met EBPG/AAMI guidelines for microbial contaminants as the mean levels of Escherichia coli in both feed and treated water were 441.7 ± 87.90 and 168.5 ± 64.03, respectively. E. coli was the commonest organism isolated in both feed and treated water in all the centers. HD water quality is still a neglected problem in our environment and more efforts are required to ensure good water quality for HD purpose. 相似文献
156.
This work is focused on spectral investigations of Tm3+ doped Sc2O3 transparent ceramic as potential material for diode-pumped solid-state laser emitting around 2 μm. In the context of the Judd-Ofelt (J-O) theory a series of spectroscopic parameters such as J-O intensity parameters, oscillator strengths, radiative transitions probabilities, and radiative lifetimes as well as branching ratios are evaluated. The gain cross-sections which lead to an estimation of the probable operating laser wavelength for the 3F4 → 3H6 Tm3+ laser transition were also calculated. 相似文献
157.
Bove CG De Dea Lindner J Lazzi C Gatti M Neviani E 《International journal of food microbiology》2011,144(3):569-572
Parmigiano Reggiano (PR) is an Italian cooked, long-ripened cheese made with unheated cow's milk and natural whey starter. The microflora is involved in the manufacturing of this cheese, arising from the natural whey starter, the raw milk and the environment. Molecular studies have shown that mesophilic non-starter lactic acid bacteria (NSLAB) are the dominant microflora present during the ripening of PR. In this study, a characterisation of Lactobacillus rhamnosus isolated from a single PR manufacturing and ripening process is reported, using a combination of genotypic fingerprinting techniques (RAPD-PCR and REP-PCR). The intraspecies heterogeneity evidenced for 66 strains is correlated to their abilities to adapt to specific environmental and technological conditions. The detection of biotypes that correlate with specific moments in cheese ripening or differential development throughout this process suggests that these strains may have specific roles closely linked to their peculiar technological properties. 相似文献
158.
159.
Weather conditions are significant hazards impacting the safe and efficient operation of aircraft. In this study, a large number of pilots were surveyed regarding weather events, and the circumstances associated with those events. Pilots completed a web-based questionnaire containing demographic questions, a risk perception scale, a hazardous events scale, and a pilot judgment scale. The pilots who reported a flight in which they penetrated weather without authorization or were concerned about the weather also completed 53 questions regarding their weather encounter. Usable data were obtained for 364 participants: 144 who reported flying into weather, 114 who experienced a flight on which weather was a concern, and 106 who reported no flights on which weather was entered or was a major concern. Significant differences were evident between the three groups on the measures of pilot judgment, personal minimums, and hazardous events where pilots flying into weather recorded the poorest scores (least conservative minimums, most hazardous events, and poorest judgment). Significant differences were also noted between the two weather groups for a number of circumstances surrounding the events. Compared to the in-weather group, pilots in the near-weather group had acquired greater instrument hours, were older, and were more likely to have an instrument rating. Their aircraft were more likely to have an autopilot. More pilots in the in-weather group (28%) reported that they would be much more careful in the future regarding weather, compared to 17% of the near-weather group. The study provides data not previously obtained on both the situational and personal characteristics that are related to involvement in different degrees of weather-related encounters. These data should promote a better understanding of these individuals and the situations in which they are involved, and should inform future research and intervention efforts. 相似文献
160.
Di Donna L Benabdelkamel H Mazzotti F Napoli A Nardi M Sindona G 《Analytical chemistry》2011,83(6):1990-1995
The quality of extra virgin olive oil is associated with the presence of microcomponents whose healing effects have been proved in some special cases. The enzymatic hydrolysis of oleuropein and ligstroside, and of their demethylated analogues, affords four different pentanedialdehydes, and for one of which, 2-(4-hydroxyphenyl)ethyl (3S,4E)-4-formyl-3-(2-oxoethyl)hex-4-enoate, also known as oleocanthal, an anti-inflammatory effect was quite recently carefully assessed. Extra virgin olive oil is now worldwide considered as a functional food whose daily intake, as for the Mediterranean diet, helps consumers in keeping a constant level of nonsteroidal anti-inflammatory drug (NSAID) in the blood. The presence of these active principles provides, therefore, olive oil with an important added value. In the framework of the actions of the recently funded Agrifood Regional Center, which should coordinate the scientific research and production worlds, an absolute analytical method was developed for the mass spectrometric detection of the two most abundant NSAIDs, Tyr-OLPD and HTyr-OLPD (oleopentanedialdehydes (OLPDs) conjugated to p-hydroxyphenylethanol and 3,4-dihydroxyphenylethanol, respectively), by UHPLC-ESI-MS/MS. 相似文献