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排序方式: 共有816条查询结果,搜索用时 296 毫秒
61.
Samuelson Kristin W.; Neylan Thomas C.; Metzler Thomas J.; Lenoci Maryanne; Rothlind Johannes; Henn-Haase Clare; Choucroun Gerard; Weiner Michael W.; Marmar Charles R. 《Canadian Metallurgical Quarterly》2006,20(6):716
Studies have shown differences in neuropsychological functioning between groups with posttraumatic stress disorder (PTSD) and control participants. Because individuals with PTSD often have a history of comorbid alcohol abuse, the extent to which an alcohol confound is responsible for these differences remains a concern. The current study compares neuropsychological testing scores in 4 groups of veterans with and without PTSD (PTSD+ and PTSD-, respectively) and with and without a history of alcohol abuse (ETOH+ and ETOH-, respectively): n for PTSD+/ETOH- = 30, n for PTSD+/ETOH- = 37, n for PTSD-/ETOH+ = 30, and n for PTSD-/ETOH- = 31. Results showed that PTSD, when alcohol, educational level, vocabulary, and depression are controlled for, was associated with decreased verbal memory, attention, and processing speed performance. Alcohol abuse history was associated with decreased visual memory performance. By controlling for alcohol and depression, the authors can more conclusively demonstrate that verbal memory and attention differences are associated with PTSD. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
PN Scutellari C Orzincolo G Castaldi F Franceschini 《Canadian Metallurgical Quarterly》1995,90(6):689-698
By definition, monoarticular arthritis means one-joint involvement, even though, in fact, such a condition is often an oligoarthritis because as many as two or three separate joints will be involved. Arthritis is often limited and may regress, so that it is frequently misdiagnosed. Sometimes, a monoarticular condition may be a polyarthritis onset (i.e., rheumatoid arthritis). Monoarticular arthritis can be caused by many factors, such as infections (septic arthritis), nonspecific inflammatory processes (reactive arthritis), crystals deposition (gout, CPPD crystal deposition disease), trauma, neoplasm (pigmented villonodular synovitis), immunologic conditions (amyloidosis) and hormonal changes (parathyroid disease). Its onset is usually acute and sometimes dramatic, with fever, pain and joint swelling, so that a decision must be made promptly to stop rapid illness evolution and to prevent the irreversible destruction of cartilage and bone (especially in septic arthritis). Diagnostic studies are performed with mono-bilateral radiographs of the joint. Radiographic findings (i.e., soft tissue swelling, joint effusion, widening and thinning of joint spaces, bone erosions and destruction of bone surface) are typical of the disease, but some findings (e.g., type of evolution and progression), laboratory tests, synovial biopsy and arthroscopy can differentiate infectious from inflammatory forms. Scintigraphy can depict isotopic joint uptake, before articular abnormalities are demonstrated with radiography, thanks to its high sensitivity; nevertheless, because of its low specificity, scintigraphy may miss some kinds of lesions (including osteoarthritis) and cannot easily differentiate osteomyelitis from septic arthritis. CT and MRI play a secondary, though not negligible, role, especially to study such deep infections as psoas abscesses, which may mimic arthritides. 相似文献
63.
PN Sambrook 《Canadian Metallurgical Quarterly》1995,333(22):1495-1496
64.
PN Tariot L Schneider AP Porsteinsson 《Canadian Metallurgical Quarterly》1997,101(6):73-6, 81, 84 passim
Treatment of Alzheimer's disease has in the past been limited to empirical trials of psychotropics for relief of behavioral complications. At present, tacrine and doneprezil are the only FDA-approved antidementia agents available. In the very near future, however, other cholinesterases inhibitors (e.g., ENA 713, metrifonate, long-acting physostigmine) are expected to be approved for clinical use. The evidence at this point suggests that they have modest but meaningful clinical effects and possible long-term benefits. Clinical use of the newer agents is likely to be influenced by their side-effect profiles, which consist largely of cholinergic effects, although without the hepatotoxic effects associated with tacrine. To what extent these agents are accepted by patients and physicians remains to be seen. On the one hand, benefits are modest; on the other, these medications are increasingly safe. Continuing research is clarifying the role of cholinergic therapy in relieving behavioral symptoms, as well as the possible side effects on rates of illness progression, institutionalizaton, and even mortality. In the not-too-distant future, physicians can expect to see a variety of medications, now in early stages of development, that are intended to affect cholinergic systems in other ways. Further down the road, a host of mechanism-based therapeutic strategies, which hope to deal with the first cause of this devastating illness, will have been assessed in clinical trials. 相似文献
65.
We report a 14 year old boy who presented as a neonate with functional pulmonary atresia due to Uhl's disease with emphasis on the later detection of restrictive right ventricular physiology. 相似文献
66.
67.
PN Levett AM Jennings KS Manning HC Harewood CR Griffith CJ Williams D Estwick BA Lashley 《Canadian Metallurgical Quarterly》1995,44(3):81-84
A pharmacoeconomic study of 15 antibiotics available in Barbados was performed. The antibiotics studied were amoxycillin/clavulanate, ampicillin, ampicillin/sulbactam, cefazolin, cefotaxime, ceftazidime, ceftriaxone, clindamycin, cloxacillin, cotrimoxazole, gentamicin, imipenem, metronidazole, piperacillin, piperacillin/tazobactam, and vancomycin. The costs of use of these compounds were calculated for a five-day course using a formula comprising eight categories: antibiotic purchase cost, maintenance of intravenous access, drug delivery cost, drug monitoring cost, dose readjustment, general monitoring cost, 'sharps' disposal cost and adverse effects. The costs of adverse effects were not included in this study due to lack of accurate data. The total cost of antibiotic use (in U.S. dollars) ranged from $42.52 to $463.73 per five-day course. Generic compounds were less expensive ($45.52 - $98.23) than brand-name compounds ($106.18 - $106.18 - $463.73). Antibiotic purchase costs accounted for proportions of total costs ranging from 7 to 93%. Non-drug costs represented a much greater proportion of total costs of generic compounds. For most compounds the non-drug costs were related to the frequency of dosing, but for gentamicin the non-drug costs were relatively higher because of the need for monitoring of serum gentamicin levels. Efficacy and freedom from side-effects will remain the most important determinants in the choice of antibiotic therapy. However, pharmacoeconomic analyses can provide prescribers with the information required to make cost-effective choices for treatment of their patients. 相似文献
68.
69.
PN Amess J Baudin J Townsend J Meek SC Roth BG Neville JS Wyatt A Stewart 《Canadian Metallurgical Quarterly》1998,40(11):724-730
Osteoporotic fractures, and in particular, hip fractures result in significant morbidity and mortality. Low bone mass is the main risk factor of enhanced bone fragility, resulting in an increased risk for hip fracture. Bone density of osteoporotic women with and without hip fractures show a considerable overlap. Therefore, other bone-independent factors also play an important role for the development of hip- and other osteoporotic fractures. One other important factor is falling. In 90% of hip fractures falling was involved [10-15], but only 5% or less of these falls resulted in a subsequent fracture. The view that adequate exercise is beneficial for skeletal health of children and for prevention and treatment of osteoporosis in adults is supported primarily by two lines of evidence: longitudinal and cross-sectional trials in children and young adult athletes showing a significant increase of muscle- and bone mass after strenuous (children) or chronic exercise (athletes) as compared to normally active (children) or sedentary control subjects. What are the potential benefits and limits of specific exercise programs with respect to bone mass, prevention of falls and fractures? In this review these questions are discussed and a specific exercise program in osteoporotic patients with fractures is delineated. 相似文献
70.
Yizhang Zhou Steven Lee Vincent G. McDonell Scott Samuelson Enrique J. Lavernia Robert L. Kozarek 《Metallurgical and Materials Transactions B》1998,29(4):793-806
Linear spray atomization and deposition is an attractive technique to produce near-net-shape deposits, such as aluminum sheet
and strip. In the present study, phase Doppler interferometry (PDI) was used in a backscatter mode to characterize, in situ, the droplet size and velocity distributions during linear spray atomization and deposition of a 3003 aluminum alloy. The
PDI measurements were obtained along axes corresponding to the direction parallel to the nozzle slit and to the direction
perpendicular to the slit. The PDI results delineate the temporal and spatial distribution of the droplet size and velocity
during the metal spray. Both point and “line” measurements were obtained and are reported. The line measurements resulted
from the integration of measurement made along a line scan obtained in real time (i.e., not ensemble averaged). Postrun analysis of the droplet size distribution using laser diffraction and sieving techniques
is also reported. The PDI point measurements revealed that droplet size and velocity distribution were relatively invariant
with time. The line measurements of droplet velocity showed that the droplet axial velocity exhibits a bimodal behavior, which
becomes more apparent with increasing atomizing gas pressure, a result of droplet recirculation inside the spray chamber.
In addition, the peak in the droplet axial velocity distribution increased as atomizing gas pressure increased. The line characterization
also showed that the droplet size distribution became more homogeneous with increasing gas pressure, and that the distribution
characteristic diameters of droplets decreased consistently with increasing gas pressure. Postrun characterization of the
droplet size distribution of the entire metal spray using diffraction and sieving methods indicated that the mass (volume)
median diameter D
50 and the Sauter mean diameter (SMD) D
32 decreased with increasing gas pressure in a manner consistent with PDI results. 相似文献