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11.
R. A. Pethrick D. Hayward K. Jeffrey S. Affrossman P. Wilford 《Journal of Materials Science》1996,31(10):2623-2629
Aluminium oxide exists in several forms which on addition of water give a complex range of oxide-hydroxide; boehmite, bayerite and gibbsite. High frequency dielectric measurements {300 kHz-3 GHz} are reported on the hydrated and dehydration of certain of these oxide-hydroxides. The amplitude of the observed dielectric relaxation correlates approximately with the water content, however anomalies can be observed during dehydration due to the retention of water in an immobilized form within the oxide matrix which highlights complexities in their structure and properties. These data indicate the potential of the dielectric method for quantification of the degree of hydration of an oxide in adhesive bonded structures. Two silane coupled alumina samples were studied to simulate the interface generated in the pre-treatment of real adhesive bonded structures. 相似文献
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The study examined whether closing of a methadone maintenance clinic in Israel on the Sabbath was associated with adverse patient outcomes. One take-home dose of methadone was given to all patients for that day regardless of whether they had earned take-home privileges. No difference was found in dropout rates for the six-month periods before and after Saturday closure was initiated. Results of random, twice-weekly urinalyses for all patients did not indicate increased use of heroin. The findings suggest that closure of a methadone clinic at least one day a week does not jeopardize patient outcome. Cutting hours of operation would reduce workload and enable clinics to function more economically. 相似文献
15.
Hayward G Lewis JE 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1989,36(3):356-364
A comparison between simulation- and measurement-based characterization is provided for the design of one-dimensional, nonadaptive, inverse filters for ultrasonic applications. Both prefiltering and postfiltering are considered by means of two different filtering strategies performed in the time and frequency domains. The results clearly indicate that theoretical methods can be used successfully, provided that the physical limitations of the simulation process are fully appreciated. In some instances, the simulation-based approach is shown to provide superior results, and the reasons for this are explained. 相似文献
16.
G Hayward 《Accident; analysis and prevention》1988,20(5):399-410
A computer-based "Home Accident Deaths Database" has been developed to permit analysis of the consumer products and articles or features of the home involved in fatal domestic accidents in England and Wales. It makes use of information already recorded for other purposes, which is either manually coded or converted by computer to a standard format. Rapid interrogation and analysis (in the form of tables or easily readable case listings) is possible, and the format of the database permits direct comparison with statistics for nonfatal hospital-treated accidents recorded by the Home Accident Surveillance System. Such comparison reveals considerable differences between the products and articles most frequently involved in fatal accidents and those most common in nonfatal cases, so that neither provides an adequate indication of hazards on its own. There are some limitations, including a variation in the level of detail recorded between different types of accident, less than perfect matching of sources for deaths in fires, and a long delay in getting cases onto the database, but with the experience that has now been gained it is hoped to develop a new reporting system that will overcome these problems and will, additionally, cover "leisure" accidents. 相似文献
17.
BT Teh S Kyt?l? F Farnebo L Bergman FK Wong G Weber N Hayward C Larsson B Skogseid A Beckers C Phelan M Edwards M Epstein F Alford D Hurley S Grimmond G Silins M Walters C Stewart J Cardinal S Khodaei F Parente L Tranebjaerg R Jorde P Salmela 《Canadian Metallurgical Quarterly》1998,83(8):2621-2626
Multiple endocrine neoplasia type 1 (MEN 1) is an autosomal dominant disease characterized by neoplasia of the parathyroid glands, the endocrine pancreas, and the anterior pituitary gland. In addition, families with isolated endocrine neoplasia, notably familial isolated hyperparathyroidism (FIHP) and familial acromegaly, have also been reported. However, whether these families constitute MEN 1 variants or separate entities remains speculative as the genetic bases for these diseases are unclear. The gene for MEN 1 has recently been cloned and characterized. Using single strand conformation analysis (SSCA) and sequencing, we performed mutation analysis in: a) a total of 55 MEN 1 families from 7 countries, b) 13 isolated MEN 1 cases without family history of the disease, c) 8 acromegaly families, and d) 4 FIHP families. Mutations were identified in 27 MEN 1 families and 9 isolated cases. The 22 different mutations spread across most of the 9 translated exons and included frameshift (11), nonsense (6), splice (2), missense mutations (2), and in-frame deletions (1). Among the 19 Finnish MEN 1 probands, a 1466del12 mutation was identified in 6 families with identical 11q13 haplotypes and in 2 isolated cases indicating a common founder. One frameshift mutation caused by 359del4 (GTCT) was found in 1 isolated case and 4 kindreds of different origin and haplotypes; this mutation therefore represents a common "warm" spot in the MEN1 gene. By analyzing the DNA of the parents of an isolated case one mutation was confirmed to be de novo. No mutation was found in any of the acromegaly and small FIHP families, suggesting that genetic defects other than the MEN1 gene might be involved and that additional such families need to be analyzed. 相似文献
18.
The development of ovulation-inducing drugs has enabled clinicians to more effectively treat the hypothalamic, pituitary, and ovarian abnormalities resulting in infertility. Pregnancy rates have been improved with the use of agents such as clomiphene citrate (CC), human menopausal gonadotropin [hMG or follicle-stimulating hormone (FSH) preparations], with gonadotropin-releasing hormone (GnRH) and its analogs, stimulating the development of multiple ovarian follicles and increasing the number of fertilizable oocytes. The use of these drugs is not without certain detrimental or "toxic" consequences. The negative effects from superovulation can occur during follicle development, decreasing the number of healthy oocytes and embryos capable of leading to viable pregnancy. Ovulation induction can lead not only to higher incidences of spontaneous abortions, and multiple and ectopic pregnancies, but also to poor pregnancy rates, due, in part, to asynchrony between embryonic development and the uterine environment. Diseases such as ovarian hyperstimulation syndrome (OHSS), resulting in the secretion of supraphysiologic levels of estradiol, can lend to severe health complications, possibly requiring hospitalization. Most drugs used for ovulation induction can lead to OHSS. Although incidences of OHSS following CC use are less frequent, CC has been associated with hot flushes, multiple gestations, visual disturbances, cervical mucus abnormalities, and luteal phase deficiency. Finally, there are reports that link any or all of the ovulation-inducing drugs with a higher incidence of ovarian and breast cancer, however, a cause-effect relationship has yet to be proven. 相似文献
19.
IP Nikitin AV Shabalin EN Ermakova AV Kytmanov NV Golyshev BM Rogachevski? SV Motorin 《Canadian Metallurgical Quarterly》1996,74(5):29-31
The study compared diagnostic potential of magnetocardiography (MCG), electrocardiography (ECG) and echocardiography (echo-CG) in 18 patients with arterial hypertension (AH). 32 healthy males served as control. Elements of MCG from normal subjects have been analyzed morphologically in 36 points of precordial leads. Left ventricular hypertrophy was registered at echo-CG, MCG, ECG in 11 (61%), 16 (84%) and 7 (34%) of the AH patients, respectively. Left atrial hypertrophy was discovered primarily by echo-CG and MCG. Defects in ventricular repolarization were recorded by MCg in 7 (39%) patients basing on MCG, echo-CG and rarely ECG signs of left ventricular hypertrophy. MCG is recommended as an effective tool in diagnosis of "hypertensive heart". 相似文献
20.
Better verification through symmetry 总被引:2,自引:1,他引:1