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排序方式: 共有451条查询结果,搜索用时 31 毫秒
151.
Braulio Macias‐Rodriguez Wade Yang Keith Schneider Cheryl Rock 《International Journal of Food Science & Technology》2014,49(11):2472-2480
The efficiency of pulsed UV light (PL) for inactivation of E. coli K12 on hard‐cooked eggs was investigated. Temperature, colour and texture were recorded to determine adverse effects on quality. Distance from the quartz window (5.5, 9.5 cm) and time (1–30 s) was set as the experimental variables. Results indicated that E. coli K12 viability decreased at closer distances and increased time (P < 0.05). Bacterial populations were reduced to 3.54 log CFU per egg and 3.23 log CFU per egg after 15 and 20 s at 5.5 cm and 9.5 cm, respectively. Scanning electron micrographs revealed the existence of photophysical mechanisms, bacterial overlapping and internalisation interfering inactivation. Treated samples experienced slight thermal increases (6–9 °C) contributing to the preservation of colour and texture, not significantly different from untreated samples (P > 0.05). Our findings support the use of PL to enhance the safety of hard‐cooked eggs although bacterial shadowing may have significant implications on treatment efficiency. 相似文献
152.
153.
OBJECTIVE: The goal of this study was to critically evaluate the predictive efficacy of various clinical factors in spinal epidural abscess influencing outcome after surgical and/or medical treatment. METHODS: A retrospective analysis of 41 cases of spinal epidural abscess treated at Henry Ford Hospital between 1984 and 1992 was performed. RESULTS: Thirty patients underwent open surgery and received antibiotic therapy, and 11 patients received medical treatment alone. After a mean follow-up period of 20.9 months (range, 4-45 mo), 24 patients (58.5%) had no or minimal deficits, 9 patients (22%) had severe paresis or plegia and/or bowel/bladder dysfunction, and 8 patients (19.5%) died. Univariate analysis revealed patient age, degree of thecal sac compression, spinal location, surgical findings, and septic presentation to be significantly associated with outcome. In multiple logistic regression analysis, increasing age and degree of thecal sac compression were the only factors with significant independent association with poor outcome (P = 0.01 for both). A simple grading system (Grades 0-III) was developed, with patient age, degree of thecal sac compression, and duration of symptoms as the determining criteria. The incidence of poor outcome for patients with Grade 0 was 0%, compared to 85.7% for patients with Grade III. CONCLUSION: We conclude that long-term outcome after treatment of spinal epidural abscess can be predicted with the use of the proposed grading scheme. Surgical drainage plus parenterally administered antibiotics remains the recommended treatment, although medical treatment alone can also be used for certain patients. 相似文献
154.
Sun Rock Choi Dongsik Kim Sung-Hoon Choa 《International Journal of Thermophysics》2006,27(5):1551-1563
The thermal diffusivity of Au, Sn, Mo, and Al0.97Ti0.03 alloy thin films, which are commonly used in microelectromechanical (MEMs) system applications, is measured by two independent methods — the ac calorimetric and photothermal mirage methods. Both methods yield similar results of the thin-film thermal conductivity, but the uncertainty of the mirage technique is found to be relatively large because of the large temperature increase during the measurement. The measured thermal diffusivities of the thin films are generally lower than those of the same bulk material. Especially, the Al0.97Ti0.03 thin film shows a pronounced thermal conductivity drop compared with bulk Al, which is believed to be mainly due to impurity scattering. Comparison of the thermal conductivity with the electrical conductivity measured by the standard four-probe technique indicates that the relation of thermal and electrical conductivities follows the Wiedemann–Franz law for the case of Au and Sn thin films. However, the Lorentz number is significantly larger than the theoretical prediction for the case of Al0.97Ti0.03 and Mo thin films. 相似文献
155.
D. N. Lee (1976) described a braking strategy based on optical expansion in which the driver brakes so that the target's time-to-contact declines around a constant slope in the range -0.5≤τ 相似文献
156.
A bismaleimide (BMI) resin was added to an epoxy system composed of N,N′-tetraglycidyldiaminodiphenyl methane (TGDDM) and diaminodiphenyl methane (DDM). Cure behavior of the BMI modified epoxy resins was studied by a dynamic differential scanning calorimetry (DSC) method. Dynamic DSC thermograms of the BMI modified epoxy resins indicated unimodal reaction exothermic peaks. The overall heat of reaction per unit mass decreased with BMI composition. The residual heat of reactions of the epoxy blends cured at 180°C for 3 h increased with BMI composition. Thermal stability of the epoxy system improved by incorporating BMI resin. Flexural strength and modulus increased with BMI composition. 相似文献
157.
Mark Crooks's article (see record 200418788-002) correctly draws attention to the ambiguous use of the notion of 'illusion' by Daniel Dennett in its arguments against theories that postulate the existence of qualia. The present comment extends that criticism by showing how Dennett's strictures reveal a failure to perceive an illusion in Dennett's own arguments. First, the inadequacy of his dismissal of inner registration is shown to be based in a prejudicial interpretation of the case for qualia. Second, his resistance to the idea of the non-epistemicity of the sensory fields shows him failing to acknowledge, not only the evolutionary advantage of such fields, but also that the flexibility and relativity of perception from person to person allows human communication to increase the rate of adaptive response across the species. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
158.
There is little in the literature that specifically explores challenges and perceived rewards faced by direct care social work practitioners who work with an inpatient AIDS population, although there are hints (Egan, 1993, Oktay, 1992, and Gilmann, 1991). This article, based on a study of 20 designated inpatient AIDS social workers at four large inner-city voluntary hospitals, will focus on challenges and rewards as perceived by social work practitioners working with the HIV infected population. The study will report commonly identified themes which include unique stressors, rewards and challenges experienced by social work practitioners working with those living with AIDS. 相似文献
159.
PE Bosted A Lung L Andivahis LM Stuart J Alster RG Arnold CC Chang FS Dietrich W Dodge R Gearhart J Gomez KA Griffioen RS Hicks CE Hyde-Wright C Keppel SE Kuhn J Lichtenstadt RA Miskimen GA Peterson GG Petratos SE Rock S Rokni WK Sakumoto M Spengos K Swartz Z Szalata LH Tao 《Canadian Metallurgical Quarterly》1992,46(6):2505-2515
160.
TL Weiland BW Scheithauer MG Rock JM Sargent 《Canadian Metallurgical Quarterly》1996,20(10):1212-1218
Two cases of inflammatory pseudotumor are described. The first patient, a 35-year-old white man, developed a progressive sensorimotor deficit in the right leg associated with a fusiform sciatic nerve mass in the posterior thigh. The lesion, compressive in nature and situated entirely within the epineurium, was totally resected. Histology revealed lymphocytic and plasmacellular inflammation as well as extensive fibrosis and collagen deposition. The patchy infiltrate consisted equally of CD2, CD3, CD5, and CD7 positive T-lymphocytes as well as CD20-and CD22-positive B-lymphocytes expressing both kappa and lambda immunoglobulin light chains. A selective biopsy of the encompassed and compressed nerve fascicles demonstrated both myelin loss and axonal injury. The second case was that of an 18-year-old woman with focal enlargement of a radial nerve by an epineurial infiltrate of multinucleate histiocytes and T as well as occasional B lymphocytes. No etiology was apparent in either case. The differential diagnosis includes non-neoplastic processes (amyloidoma and tuberculoid leprosy) as well as tumors (benign and malignant peripheral nerve sheath tumors, lymphoma). Although rare, inflammatory pseudotumors must be included in the differential diagnosis of tumor-like lesions of peripheral nerve. 相似文献