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The objective of the current study was to develop an in vitro testing protocol to evaluate semi-rigid pedicle screw devices. A corpectomy model protocol exists to evaluate rigid spinal implants; however, semi-rigid devices are contraindicated for this condition. This paper describes a technique that simulates more closely the conditions a semi-rigid device would see in vivo. Finally, the new testing protocol is used to evaluate the DDS pedicle screw-cable system. Benefits and shortcomings of the new protocol are discussed. 相似文献
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Elastofibroma, or elastofibroma dorsi as it was first described, is an uncommon tumor-like process that characteristically appears as an ill-defined mass in the infrascapular region of elderly patients. This lesion can occur bilaterally and may appear asynchronously. The occurrence of elastofibroma in other anatomic sites has been reported, although with much less frequency. Elastofibromas display typical diagnostic histologic, cytologic, and electron microscopic features. The use of magnetic resonance imaging can lead to a presumptive diagnosis in elderly individuals with suprascapular lesions. It is important to differentiate this lesion from other soft-tissue lesions, such as sarcomas and desmoid tumors. This study presents a case of bilateral elastofibromas in a 72-year-old man and a review of the literature. 相似文献
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M Karayiorgou L Kasch VK Lasseter J Hwang R Elango DJ Bernardini M Kimberland R Babb CA Francomano PS Wolyniec 《Canadian Metallurgical Quarterly》1994,54(4):345-353
Our collaborative group has undertaken a linkage study of schizophrenia, using a systematic sample of patients admitted to Maryland hospitals. An initial sample of 39 families, each having two or more affecteds, was available for genotyping candidate genes, candidate regions, and highly polymorphic markers randomly distributed throughout the genome. We used a single complex dominant model (with a disease gene frequency of 0.005 and age-dependent penetrance for affected phenotype: for under 35, penetrance = .45; for 35 and older, penetrance = .85). We report here 130 markers, which met the exclusion criteria of LOD score < -2.00 at theta > 0.01 in at least 10 informative families, and no evidence for heterogeneity. We also report here markers that were tested as candidates for linkage to the schizophrenic phenotype. They were selected based on the following criteria: a) proximity to reported chromosomal rearrangements (both 5q and 11q), b) suggestions of linkage from other families (5q), or c) presence of a candidate gene (5q, 11q, 3q: Dopamine receptors 1, 2, and 3, respectively). We also tested for mutations of codon 717 in exon 17 of the amyloid precursor protein (APP) gene and were unable to detect the C to T substitution in our schizophrenic group. 相似文献
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VK Ovcharov 《Canadian Metallurgical Quarterly》1998,97(4):23-27
Today, when the number of high-risk patients is increasing, special attention should be paid to polyresistant gram-positive microorganisms staphylococci and enterococci, whose role in infective complications and septic states is increasing. The author analyzes published reports on the rate of isolation of methicillin-resistant staphylococci (MRS) and enterococci in different countries and relationship of this parameter with antibiotic policy. Special attention is paid to unjustified wide use of third-generation cephalosporines and their role in selection of polyresistant bacteria. The rate of MRS isolation vs. all other staphylococci at intensive care wards for newborns is as high as 63.9%. The incidence of coagulase-negative staphylococci (most often S. epidermidis) in clinical material (blood, cerebrospinal fluid, urine) from high-risk patients increased 2-3 times during two recent years. Glycopeptides vancomycin and teicoplanine are drugs of choice for the treatment of infections caused by such microorganisms (sepsis, endocarditis, osteomyelitis, pneumonia, etc.). These drugs should be listed among obligatory antibiotics for resuscitation and intensive care wards as life-saving drugs. 相似文献
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VK Sharma JR Copeland ME Dewey D Lowe I Davidson 《Canadian Metallurgical Quarterly》1998,28(6):1329-1337
BACKGROUND: Comparatively little is known about the long-term natural history of depressive disorders in the elderly living in the community. This is a follow-up of a subsample of the Continuing Health in the Community study random sample of the elderly population living in Liverpool. METHODS: The investigators followed up 120 cases of depression identified by a semi-structured interview schedule (GMS) for a period of 5 years. A similar number of other subjects defined as subcases of depression, other cases of mental illness and a random selection of non-cases were also included. RESULTS: The 5-year outcome for the cases of depression was worse than the outcome of the non-cases (relative mortality risk of 2.1, 95% confidence interval 1.1 to 3.9). Thirty-four per cent of the cases of depression died and 28% had dropped out during the follow-up. Of the 46 cases of depression who had a complete follow-up, 22% recovered from their symptoms, 30% were found to be AGECAT cases at one of the three follow-up waves, 24% were AGECAT cases at two of the three follow-up waves and the remaining 24% were AGECAT cases at each follow-up wave. Fifteen per cent of the surviving cases of depression were organic cases at the follow-up. Their anxiety comorbid state and depression score were identified as predictors of poor outcome. CONCLUSION: The findings of this study indicate that depressive disorders (most of which were untreated) found in the elderly community have a poor prognosis. 相似文献
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Microcirculatory disorders in cerebral ischemia in rats and their correction by using leu-enkephalin
Leu-enkephalin (LE) induced mainly a constriction of pial arterioles, diameter of the venules did not change. The effect of the LE involved preservation of the cerebral blood flow and that in microvessels, constriction of some arterioles and reduced dilatation against the background of decreased arterial pressure, bradycardia, increased lymphatic flow and survival of the animals during first hours of occlusion of common carotid arteries. 相似文献