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901.
A long-term outcome study of 170 surgically treated patients with compressive cervical radiculopathy
RA Davis 《Canadian Metallurgical Quarterly》1996,46(6):523-30; discussion 530-3
BACKGROUND: There is a general impression that publications in neuro-surgical journals have comprehensively evaluated the relative merits of various operative techniques with long-term follow-up in patients treated for compressive cervical radiculopathy. However, in some 20,000 neurosurgical papers over the past 50 years, only 74 (0.3%) have addressed this common surgical problem. METHODS: Long-term outcome was assessed by the standardized Functional Economic Outcome Rating Scale of Prolo. Information was obtained primarily by telephone interviews and office visits. No patients were operated upon without a confirmatory neuroradiologic study. Single level soft discs were removed through a posterior-lateral foraminotomy with hemilaminectomy or laminectomy the root was decompressed by the same technique with hard discs. RESULTS: One hundred seventy patients were operated on from 1959-91 with a 96% follow-up. The mean follow-up period was 15 years. Patients who had sedentary occupations and housewives, had statistically higher Economic Prolo scores (p < 0.001) than those who did strenuous work. Of 10 patients with a total Prolo score of 5 or less, seven did strenuous work and had Workers' Compensation claims; the remaining had legal claims or were at psychologic risk for operation. In 86% of patients outcome was good; defined as a Prolo score of 8 in 5%, 9 in 38%, and 10 in 43%. Of 10 recurrences (6%), seven occurred within 3 years after operation and were treated by discectomy and anterior cervical fusion. There were two patients with postoperative deltoid motor weakness who recovered within 1 year. CONCLUSIONS: Although outcome studies must have subjective criteria, the Prolo Scale is more objective and quantitative than currently used methods. The posterior approach to disc lesions causing compressive cervical radiculopathy should be compared to other techniques using the Prolo Outcome Scale. 相似文献
902.
Active sequences from the laminin alpha1 and alpha2 chain carboxyl-terminal globular domains (G domain) have been identified by screening overlapping synthetic peptides in a number of biological assays (Nomizu et al. [1995] J. Biol. Chem. 270:20583-20590; Nomizu et al. [1996] FEBS Lett. 396:37-42). We have tested the activity of these peptides in submandibular gland explants of embryonic day 13 mice to determine the functional sites involved in organ development. The laminin alpha1 chain peptide, RKRLQVQLSIRT (residues 2719-2730 and designated AG-73), significantly inhibited epithelial branching morphogenesis. In contrast, other cell adhesive laminin alpha1 chain peptides including the AASIKVAVSADR and NRWHSIYITRFG failed to inhibit the branching. MG-73, a homologue of AG-73 from the laminin alpha2 chain, did not inhibit the branching. The alpha2 chain peptide had no effect, which may be due to the low levels of this laminin chain in day 13 mice. Laminin alpha2 chain-specific monoclonal antibodies strongly reacted with the basement membranes of developed acini but only weakly stained embryonic day 13 submandibular epithelium. The expression of E-cadherin and alpha6 integrin, as detected by immunofluorescence, were unchanged in both AG-73 and control scramble peptide-treated epithelial cells of the explants. In contrast, immunostaining of nidogen/entactin showed that explants treated with AG-73 for 3 days had a discontinuous basement membrane. Explants treated for 3 days with control peptide showed a normal basement membrane. These results suggest that the region containing the AG-73 sequence of the laminin alpha1 chain is crucial for development of submandibular gland at early embryonic stages. The discontinuous basement membrane in AG-73-treated explants may indicate an important role for this region in basement membrane assembly. 相似文献
903.
A perspective is offered on the perspective of U.S. industry on the need for a next step facility for fusion energy development. 相似文献
904.
Sutker Patricia B.; Davis J. Mark; Uddo Madeline; Ditta Shelly R. 《Canadian Metallurgical Quarterly》1995,104(3):444
Posttraumatic stress disorder (PTSD) can occur subsequent to war stress, but not all troops are negatively affected. A discriminant function model was used to study associations between personal and environmental resources and psychological outcomes subsequent to war zone stress. Among 775 Persian Gulf War exposed troops, 2 subsets were identified: 97 with PTSD diagnoses and 484 who had no psychological distress. A discriminant function, double cross-validated in random subsamples, classified 87% of troops, and demographic and stress severity variables did not alter results significantly. Personality hardiness commitment, avoidance coping, and perceived family cohesion emerged as consistent predictors of PTSD diagnosis. Findings suggest personal characteristics and environmental factors may alter vulnerability to negative war stress outcomes. Work is needed to identify mechanisms and causal pathways by which resource factors enhance or lower stress resistance. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
905.
B Houltz B Darp? N Edvardsson P Blomstr?m J Brachmann HJ Crijns SM Jensen E Svernhage H Vallin K Swedberg 《Canadian Metallurgical Quarterly》1998,21(5):1044-1057
The aim of this study was to identify predictors of torsades de pointes (TdP) in patients with atrial fibrillation (AF) or flutter exposed to the Class III antiarrhythmic drug almokalant. TdP can be caused by drugs that prolong myocardial repolarization. One hundred patients received almokalant infusion during AF (infusion 1) and 62 of the patients during sinus rhythm (SR) on the following day (infusion 2). Thirty-two patients converted to SR. Six patients developed TdP. During AF, T wave alternans was more common prior to infusion (baseline) in patients developing TdP (50% vs 4%, P < 0.01). After 30 minutes of infusion 1, the TdP patients exhibited a longer QT interval (493 +/- 114 vs 443 +/- 54 ms [mean +/- SD], P < 0.01), a larger precordial QT dispersion (50 +/- 74 vs 27 +/- 26 ms, P < 0.05), and a lower T wave amplitude (0.12 +/- 0.21 vs 0.24 +/- 0.16 mV, P < 0.01). After 30 minutes of infusion 2, they exhibited a longer QT interval (672 +/- 26 vs 489 +/- 74 ms, P < 0.001), a larger QT dispersion in precordial (82 +/- 7 vs 54 +/- 52 ms, P < 0.01) and extremity leads (163 +/- 0 vs 40 +/- 34 ms, P < 0.001), and T wave alternans was more common (100% vs 0%, P < 0.001). Risk factors for development of TdP were at baseline: female gender, ventricular extrasystoles, and treatment with diuretics; and, after 30 minutes of infusion: sequential bilateral bundle branch block, ventricular extrasystoles in bigeminy, and a biphasic T wave. Patients developing TdP exhibited early during almokalant infusion a pronounced QT prolongation, increased QT dispersion, and marked morphological T wave changes. 相似文献
906.
SM Albert M Sano K Bell C Merchant S Small Y Stern 《Canadian Metallurgical Quarterly》1998,38(6):704-714
People with Alzheimer's disease living in a defined community in New York City were identified and assessed on two occasions to determine the number of hours of activities of daily living (ADL) care they received. Nearly half received all care hours from informal sources; however, a quarter received all ADL care hours from formal sources. The mean number of daily ADL hours in the sample was 9.7, of which 4.2 came from formal sources. This reflects the extensive use of Medicaid-based home care services in New York City. As dementia worsened, substitution of formal for informal care was rare, but formal care assumed a greater proportion of total care hours. 相似文献
907.
908.
ML Doherty ML Monaghan HF Bassett PJ Quinn WC Davis 《Canadian Metallurgical Quarterly》1996,49(4):307-320
Nine M. bovis-infected cattle on a diet deficient in both protein and energy for 133 days lost approximately 17% of their original body weight. However, dietary restriction did not result in any significant reduction in skin sensitivity to PPD, in vitro production of IFN-gamma or lymphocyte blastogenesis. The number of circulating BoCD4+ cells and B cells were similar in both the malnourished and the control cattle. However, significantly lower numbers (P < 0.01) of circulating BoCD2+ cells, BoCD8+ cells, WC1+ gamma delta T cells and ACT2+ cells were found in the malnourished cattle. With the exception of inorganic phosphate, the changes in plasma biochemical parameters were unremarkable. 相似文献
909.
RH B?ger SM Bode-B?ger RP Brandes L Phivthong-ngam M B?hme R Nafe A Mügge JC Fr?lich 《Canadian Metallurgical Quarterly》1997,96(4):1282-1290
BACKGROUND: We investigated whether L-arginine induces regression of preexisting atheromatous lesions and reversal of endothelial dysfunction in hypercholesterolemic rabbits, whether similar effects can be obtained by cholesterol-lowering therapy with lovastatin, and which mechanism leads to these effects. METHODS AND RESULTS: Rabbits were fed 1% cholesterol for 4 weeks and 0.5% cholesterol for an additional 12 weeks. Two groups of cholesterol-fed rabbits were treated with L-arginine (2.0% in drinking water) or lovastatin (10 mg/d) during weeks 5 through 16. Systemic nitric oxide (NO) formation was assessed as the urinary excretion rates of nitrate and cGMP in weekly intervals. Cholesterol feeding progressively reduced urinary nitrate excretion to approximately 40% of baseline (P<.05) and increased plasma concentrations of asymmetrical dimethylarginine (ADMA), an endogenous NO synthesis inhibitor. Dietary L-arginine reversed the reduction in plasma L-arginine/ADMA ratio and partly restored urinary excretion of nitrate and cGMP (each P<.05 vs cholesterol) but did not change plasma cholesterol levels. L-Arginine completely blocked the progression of carotid intimal plaques, reduced aortic intimal thickening, and preserved endothelium-dependent vasodilator function. Lovastatin treatment reduced plasma cholesterol by 32% but did not improve urinary nitrate or cGMP excretion or endothelium-dependent vasodilation. Lovastatin had a weaker inhibitory effect on carotid plaque formation and aortic intimal thickening than L-arginine. L-Arginine inhibited but lovastatin potentiated superoxide radical generation in the atherosclerotic vascular wall. CONCLUSIONS: Dietary L-arginine improves NO-dependent vasodilator function in cholesterol-fed rabbits and completely blocks the progression of plaques via restoration of NO synthase substrate availability and reduction of vascular oxidative stress. Lovastatin treatment has a weaker inhibitory effect on the progression of atherosclerosis and no effect on vascular NO elaboration, which may be due to its stimulatory effect on vascular superoxide radical generation. 相似文献
910.
DaSilva L.A. Midkiff S.F. Park J.S. Hadjichristofi G.C. Davis N.J. Phanse K.S. Tao Lin 《Communications Magazine, IEEE》2004,42(11):88-96
The integration of various network-level functions, including routing, management, and security, is critical to the efficient operation of a mobile ad hoc network. In this article we focus on network mobility (rather than node mobility), implying the movement of entire subnetworks with respect to one another, while individual users initially associated with one such subnetwork may also move to other domains. One example is a battlefield network that includes ships, aircraft, and ground troops. In this "network of networks", subnets (e.g. shipboard networks) may be interconnected via a terrestrial mobile wireless network (e.g., between moving ships). We discuss the design and implementation of a new ad hoc routing protocol, a suite of solutions for policy-based network management, and approaches for key management and deployment of IPsec in a MANET. These solutions, in turn, are integrated with real-time middleware, a secure radio link, and a topology monitoring tool. We briefly describe each component of the solution, and focus on the challenges and approaches to integrating these components into a cohesive system to support network mobility. We evaluate the effectiveness of the system through experiments conducted in a wireless ad hoc testbed. 相似文献