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排序方式: 共有90条查询结果,搜索用时 31 毫秒
1.
EO Johnson MB van den Bree AE Gupman RW Pickens 《Canadian Metallurgical Quarterly》1998,22(7):1421-1429
Mild, severe, and dyssocial subtypes of alcohol dependence, previously identified among Caucasian men from the Epidemiologic Catchment Area study, were also identified among Caucasian men and women with DSM-IV alcohol dependence from the National Longitudinal Alcohol Epidemiologic Survey (n = 2,703; 1,746 respectively). These subtypes were not identified among African American and Hispanic American men or women with DSM-IV alcohol dependence. Among Caucasians with alcohol dependence, the subtypes were characterized by differential loading on three dimensions: genetic, general environmental, and dyssocial environmental symptom scales developed in a prior twin study. The mild subtype (60% of men and 66% of women) was distinguished by low mean scores on all three scales; the dyssocial subtype (24% of men and 20% of women) by low mean genetic and general environmental scores but high mean dyssocial environmental scores; and the severe subtype (16% of men and 14% of women) by high scores on the genetic and general environmental scales. These subtypes also showed the expected distinctions in clinical characteristics. The severe subtype showed greater comorbid drug dependence and major depression, more treatment seeking, and a higher prevalence of parental alcoholism. The severe subtype also showed significantly greater genetic influence adjusted for overall severity of alcohol dependence (genetic ratio). Only the severe subtype showed a pattern of scale scores and clinical characteristics suggestive of substantial genetic influence. The present study indicates a robustness of the typology originally developed among DSM-III alcohol-dependent Caucasian men by empirical extension of the subtypes to a different sample of Caucasian men and, separately, Caucasian women. The use of this typology may aid in distinguishing between Caucasian alcohol-dependent individuals on the basis of relative genetic influence, enabling genetic, behavioral, and epidemiological investigations to reduce genetic or environmental "noise" and better focus on specific aspects of alcohol dependence. 相似文献
2.
Agnieszka Owczarek‐Fendor An Vermeulen Ilse Van Bree Markus Eriksson Stefaan Lescouhier Stefaan De Smet Bruno De Meulenaer Frank Devlieghere 《International Journal of Food Science & Technology》2014,49(4):1090-1098
The objective of this study was to evaluate the influence of two different vacuum ageing times (7 and 14 days) and the impact of the modified atmosphere packaging (MAP) configuration (gas/product ratios: 0.5 and 1 and gas composition: 70% O2 + 30% CO2 and 40% O2 + 30% CO2 + 30% N2) on the quality of fresh beef during subsequent storage at 4 °C. For this purpose, three separate experiments were performed. For each experiment, two different muscles (Longissimus dorsi and Biceps femoris) were sampled from four double‐muscled Belgian Blue beef carcasses. Next to colour, also the evolution in microbial load, pH, O2 and CO2 in the headspace and lipid oxidation at the meat surface were evaluated. A vacuum ageing for 14 days compared with 7 days resulted in a higher initial microbial load on the day of MAP packaging, which resulted finally in a significantly shorter shelf life. This ageing effect was less pronounced on the colour stability and lipid oxidation of the meat samples. No significant influence of the packaging configuration on any of the analysed parameters (colour, microbial load, pH and lipid oxidation at the meat surface) was observed. 相似文献
3.
In order to explore the differing theoretical predictions of the cues-filtered-out perspective, SIDE model, and hyperpersonal model for online-to-offline relationships outside of the laboratory, a longitudinal survey study was conducted. Participants from a large online message board community who met up with an online acquaintance face-to-face completed surveys regarding their relationship with that individual before and after meeting their acquaintance face to face. Results indicated that the amount of communication with the online acquaintance was related to greater relation development whereas connection to the group was only related to greater individual closeness not satisfaction or predicted outcome value. In general the face-to-face meeting resulted in improved closeness, satisfaction, and predicted outcome value. An exploration for curvilinear effects as predicted by the hyperpersonal model revealed that predicted outcome value at time 1 had a curvilinear effect on closeness at time 2. 相似文献
4.
R de Bree RP Chung J van Aken MW van den Brekel 《Canadian Metallurgical Quarterly》1998,142(29):1676-1680
Laryngeal tuberculosis was diagnosed in two men, a 73-year-old man Dutch by birth and a 40-year-old one Turkish by birth. In the former patient it was probably primary tuberculosis, in the latter secondary (he had lung tuberculosis as well). The clinical picture was highly suggestive of laryngeal carcinoma in both patients. They both recovered with chemotherapy. Laryngeal tuberculosis may mimic laryngeal carcinoma. The diagnosis is based on Ziehl-Neelsen staining, culture and polymerase chain reaction (PCR) on Mycobacterium tuberculosis. Because laryngeal tuberculosis is highly infectious, the patient has to be nursed in isolation and people in his or her environment have to be screened. The response of laryngeal tuberculosis to chemotherapy is good. 相似文献
5.
A dose of 200 cGy of total-body irradiation (TBI) is nonlethal in dogs: Following a granulocyte nadir in the third week post-TBI, peripheral blood cell counts recover to normal values by about 5 weeks. In the context of studies on a potential role of major histocompatibility (MHC) class II antigens in the regulation of stress hematopoiesis, we tested the effect of anti-MHC class II monoclonal antibodies (mAbs) on hematologic recovery after TBI. Thirteen dogs were given 200 cGy of TBI not followed by marrow infusion. Five received no additional treatment (concurrent controls) and eight were given daily intravenous (IV) injections of anti-class II mAbs H81.9 (anti-HLA-DR; n = 6) or B1F6 (anti-HLA-DR and -DP; n = 2) at 0.6 (n = 4) or 1.2 mg/kg/d (n = 4) on days 0-4 (n = 7) or days 0-9 (n = 1). One control dog died early from an intercurrent infection and four recovered uneventfully. Dogs given mAbs after TBI showed significantly different granulocyte and platelet kinetics. The granulocyte nadir was lower (p = 0.09) and was reached later (p = 0.005), the duration of neutropenia was longer (p = 0.08), and recovery occurred later (p = 0.02) than among controls. Similarly the platelet nadir was lower (p = 0.05), thrombocytopenia lasted longer (p = 0.02), and recovery occurred later (p = 0.02) than among controls. Four of eight mAb-treated dogs died with marrow aplasia. We propose that following irradiation, HLA-DR mediated signals result in terminal differentiation in more mature hematopoietic precursors but interfere with replication or differentiation in early hematopoietic precursors. These observations suggest a role for MHC class II molecules in the regulation of stress hematopoiesis. 相似文献
6.
Hill T.F. Velasquez-Garcia L.F. Wilhite B.A. Rawlins W.T. Seonkyung Lee Davis S.J. Jensen K.F. Epstein A.H. Livermore C. 《Journal of microelectromechanical systems》2007,16(6):1492-1505
This paper reports the quantitative experimental exploration of the performance space of a microfabricated singlet oxygen generator (muSOG). SOGs are multiphase reactors that mix H2O2, KOH, and Cl2 to produce singlet delta oxygen, or O2 (a). A scaled-down SOG is being developed as the pump source for a microfabricated chemical oxygen-iodine laser system because scaling down a SOG yields improved performance compared to the macroscaled versions. The performance of the muSOG was characterized using O2 (a) yield, chlorine utilization, power in the flow, molar flow rate per unit of reactor volume, and steady-state operation as metrics. The performance of the muSOG is measured through a series of optical diagnostics and mass spectrometry. The test rig, which enables the monitoring of temperatures, pressures, and the molar flow rate of O2 (a), is described in detail. Infrared spectra and mass spectrometry confirm the steady-state operation of the device. Experimental results reveal O2 (a) concentrations in excess of 1017 cm-3, O2 (a) yield at the chip outlet approaching 80%, and molar flow rates of 02(a) per unit of reactor volume exceeding 600 times 10-4 mol/L/s. 相似文献
7.
Aravind Suresh Joysurya Basu C. Barry Carter Nigel Sammes B. A. Wilhite 《Journal of Materials Science》2010,45(12):3215-3227
Cobalt-doped barium cerate-zirconate was synthesized using an oxalate co-precipitation route. The material was characterized
using X-ray diffraction, transmission and scanning transmission electron microscopy coupled with X-ray energy dispersive spectroscopy.
Results indicated that homogeneous cubic phase material was obtained at very high heat-treatment temperatures. Catalytic activity
of the material toward CH3OH partial-oxidation was tested at different temperatures and O2:CH3OH ratios. High hydrogen yields were obtained indicating that the material was a suitable catalyst for hydrogen generation.
Impedance spectroscopy tests were conducted at different conditions to understand conduction processes occurring in the material.
Results suggested mixed protonic–electronic conductivity in the presence of hydrogen. Thus, material is a potential candidate
for the bi-functional role of electro-ceramic catalyst for simultaneous hydrogen generation and purification. 相似文献
8.
9.
Abstract Patterns of water supply and use in Australia and the U.S.A. differ in many ways. This results in different perceptions concerning the nature of drought and policy approaches to its management. This paper discusses the differences and similarities and explores lessons that policy makers in both countries can learn from one another. A key difference between the two countries is that whereas drought is perceived in Australia essentially in terms of its impact on agriculture, in the U.S. both perceptions and policy are also heavily influenced by the impact of drought on urban communities. This has led to different policy emphases. In 1992 Australia established its National Drought Policy; the U.S. is presently considering the adoption of a national drought policy. These policies highlight drought being accepted as part of natural climate variability, rather than as a natural disaster. They also emphasize the protection of the natural resource base. 相似文献
10.
JM Balter KL Lam HM Sandler JF Littles RL Bree RK Ten Haken 《Canadian Metallurgical Quarterly》1995,33(5):1281-1286
PURPOSE: Prostate movement is a major consideration in the formation of target volumes for conformal radiation therapy of prostate cancer. The goal of this study was to determine the technical feasibility of using implanted radiopaque markers and digital imaging to localize the prostate at the time of treatment, thus allowing for reduction of the margin required for uncertainty in target position. METHODS AND MATERIALS: Radiopaque markers implanted around the prostate prior to treatment are visible on electronic radiographs generated with a portal imager or diagnostic imaging device. The locations of the images of these markers on the digital radiographs were automatically determined by a template-matching algorithm. The coordinates of the markers were found by projecting rays through the marker locations on orthogonal radiographs using a three-dimensional (3D) point-matching algorithm. Prostate and/or patient movement was inferred from the marker displacements. Images generated from known movements of a phantom with implanted markers were tested with this algorithm. Locations of markers from daily images of patients with implanted markers were determined by both manual and automatic techniques to determine the efficacy of automated localization on typical clinical images. RESULTS: Prostate movements can be automatically detected in a phantom using low-energy photons within 30 s after image acquisition and with a precision of better than 1 mm in translation and 1 degree in rotation (indistinguishable from the uncertainty in measuring precision). CONCLUSION: The studies show that on-line repositioning of the patient based on localization of the markers at the time of treatment is feasible, and may reduce the uncertainty in prostate location when combined with practical on-line repositioning techniques. 相似文献