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991.
A large body of information suggests NSAIDS have a negative impact on the healing of bone. Although each clinical healing scenario presents a slightly different level of challenge, the healing of a posterolateral spinal fusion is one of the most difficult challenges in bony healing. Clinically, this results in a relatively high rate of nonunions using traditional fusion techniques. Spinal fusion models have confirmed NSAIDS have a definite inhibitory effect on healing of the fusion. Although data are limited, it appears this effect is most severe when NSAIDS are administered in the early postoperative period. Moreover, the effect may be worse with certain types initial inflammatory, subsequent reparative, and final remodeling phases. Because of the anti-inflammatory activity of NSAIDS, one might assume their effects would be worse when administered in the inflammatory phase. Indeed, the study by Riew et al suggests the inhibitory effects are more significant when NSAIDS are administered earlier following fusion. Other studies conducted with non-spinal models also suggest early administration of NSAIDS results in greater inhibition of bone formation (Goodman et al). Unfortunately, the length of the inflammatory phase in humans is not well known. This leaves the clinician unsure about the safe time to allow resumption of NSAID usage clinically. It appears likely NSAID use following a spinal fusion procedure will increase the rate of pseudarthrosis. The literature suggests that avoidance of NSAIDS in the postoperative period may avoid nonunion. Additionally, we propose that chronic NSAID usage should be addressed in a similar manner to cigarette smoking. While neither are absolute contraindications to elective spinal fusion, patients should be counseled to discontinue the use of NSAIDS in the peri- and postoperative period to maximize their chance for a successful fusion. 相似文献
992.
Alex?SheffieldEmail author Glenn?Waller Francesca?Emanuelli James?Murray Caroline?Meyer 《Cognitive therapy and research》2005,29(6):787-802
This study describes the psychometric validation of the young parenting inventory (YPI), and tested specific hypotheses regarding
the link between one’s experience of their parent’s behaviors and the development of schema-level core beliefs. The YPI is
a measure of perceived parenting experiences, hypothesized to represent the origins of negative core beliefs. This preliminary
validation consisted of analyses of factor structure, internal consistency, test–retest reliability, and construct validity.
A large non-clinical student sample (N = 422) completed the YPI, and a subset also completed the Young Schema Questionnaire-Short form (YSQ-S). Factor analyses demonstrated
that a shorter version of the questionnaire (YPI-R) could be developed to represent coherent and meaningful perceptions of
each parent. The YPI-R consists of nine scales. Each scale had good test–retest reliability and adequate internal consistency.
Significant associations between the YPI-R scales and negative core beliefs (as measured by the YSQ-S) indicated partial construct
validity. At this preliminary stage, it can be concluded that the YPI-R has an acceptable level of psychometric utility. However,
the hypothesized parenting-negative core belief links were not all substantiated. 相似文献
993.
The aim of this in vitro study was to evaluate by spectrophotometry the influence of the incremental technique and progressive light curing in the microleakage of Class V cavities. Forty samples were prepared with class V cylindrical cavities on the buccal root surface of bovine incisive teeth and filled with composite resin (Z250). The samples were divided into four groups: I: cavity was bulk filled and the composite was light cured for 40 seconds; Group II: cavity was bulk filled and a 'soft-start" polymerization was used; Group III: cavity was filled with the incremental technique in two coats and light cured for 40 seconds; Group IV: cavity was filled with the incremental technique in two coats and light cured with "soft-start" polymerization. After the restoration, the specimens were thermally stressed for 3,000 cycles in bath at 5 +/- 2 degrees C and 55 +/- 2 degrees C, protected with nail enamel, colored with 2% methylene blue and cut into sections. These sections were triturated and the dye was recovered with PA ethanol and the supernatant was evaluated. The data were submitted to ANOVA and the results showed the following averages: bulk filled and conventional photopolymerization (I) 0.06075 microg/ml; bulk filled and progressive photopolymerization (II) 0.04030 microg/ml; incremental insertion and conventional photopolymerization (III) 0.04648 microg/ml; incremental insertion and progressive photopolymerization (IV) 0.04339 microg/ml. No significant statistic differences were observed among the mean values. The Degulux "soft-start" equipment probably emits too high initial light intensity to promote progressive photopolymerization. 相似文献
994.
The effect of heat on tissue extensibility: a comparison of deep and superficial heating 总被引:1,自引:0,他引:1
OBJECTIVE: To compare the effects of deep heating (shortwave diathermy [SWD]) and superficial heating (hydrocollator packs) on tissue extensibility. DESIGN: A double-blind, repeated-measures study. Possible effects of sex and intervention order were controlled. SETTING: A clinical laboratory. PARTICIPANTS: Twenty-four subjects with no neurologic or musculoskeletal pathologies affecting their lower limbs. INTERVENTIONS: Three intervention conditions: deep heating (SWD), superficial heating (hot packs), and no heating were applied in preallocated order to each subject at least 36 hours apart. MAIN OUTCOME MEASURES: Ankle dorsiflexion in weight bearing was measured by using an inclinometer to ascertain changes in the extensibility of the calf muscles and associated soft tissues. RESULTS: Deep heating increased the range of ankle dorsiflexion by 1.8 degrees +/-1.9 degrees . The change in ankle dorsiflexion after superficial and no heating was 0.7 degrees +/-1.5 degrees and -0.1 degrees +/-1.0 degrees , respectively. CONCLUSIONS: Deep heating, in the absence of stretching, increases tissue extensibility more than superficial heating or no heating. Superficial heating is more effective than no heating, but the difference was not statistically significant. 相似文献
995.
Zihlmann MS Stacoff A Romero J Quervain IK Stüssi E 《Clinical biomechanics (Bristol, Avon)》2005,20(7):661-668
Malalignment, in particular femoral component malrotation, is a commonly accepted failure mode in total knee arthroplasty. The general objective of this paper is twofold: firstly, it accentuates clinical observations of the effects of rotational malalignment in total knee arthroplasty. Secondly, it discusses the relevant parameters of existing knee joint models with regards to rotational malalignment and its biomechanical background, thereby setting a basis for future studies. To summarise, when modelling malalignment in total knee arthroplasty, the following aspects should be considered: Friction between the implant components, ligamentous and capsular structures, deformable body to model the PE inlay, and an in vivo validation of the model. Because of the large variance in anthropometrical data between individuals, future knee joint models should also incorporate individual data. 相似文献
996.
Ben-Dor I Sagie A Weisenberg D Ben Zekry S Fraser A Sahar G Iakobishvili Z Battler A Shapira Y 《The American journal of cardiology》2005,96(11):1549-1552
Aortic root dilation has been previously reported to be associated with aortic stenosis (AS), but data to support this statement are scarce. The dimensions of the aortic root were measured at 4 levels (annulus, sinuses, sinotubular junction, and ascending aorta) in 88 patients (mean age 71.2+/-9.7 years; 56% men) with severe AS who underwent intraoperative transesophageal echocardiography immediately before aortic valve replacement. These patients were compared with 76 gender- and age-matched patients without AS who underwent transesophageal echocardiography for various indications. The etiology of aortic valve stenosis was degenerative in 62 (70.5%), bicuspid aortic valve (BAV) in 15 (17.0%), and rheumatic in 11 (12.5%). The ascending aorta was significantly wider in AS with various etiologies (BAV, rheumatic, degenerative) than in the controls (39+/-6.9, 35.0+/-4.2, 33.1+/-4.1, and 31.3+/-3.7 mm, respectively; p<0.001). The dimensions of the sinuses and sinotubular junction were significantly less in those with AS of degenerative etiology than in the controls (29.5+/-4.0 vs 32.5+/-4.3 mm and 23.6+/-3.0 vs 26.8+/-3.0 mm, respectively, p<0.001). The prevalence of a dilated aorta (>37 mm) was 3.9%, 13.1%, 36.4%, and 60% in the control group and AS patients with degenerative, rheumatic, and BAV etiology, respectively (p<0.0001). In conclusion, patients with severe AS due to BAV had significant dilation of the aortic root. Patients with degenerative and rheumatic etiology had less remarkable dilation compared with control group, and most values were within the normal range. 相似文献
997.
Promoting informed choice: transforming health care to dispense knowledge for decision making 总被引:1,自引:0,他引:1
Woolf SH Chan EC Harris R Sheridan SL Braddock CH Kaplan RM Krist A O'Connor AM Tunis S 《Annals of internal medicine》2005,143(4):293-300
Ours is an era in which patients seek greater engagement in health care choices, increasing the demand for high-quality information about clinical options. Providing support for informed choice is not straightforward, however, because of challenges faced by clinicians, health systems, and consumers. Greater use of written or electronic tools can help to clarify choices for patients, but decision aids cannot replace the human element in facilitating informed choice. The ideal solution is to couple information with high-quality decision counseling to help patients understand the potential risks, benefits, and uncertainties of clinical options and to assist them in selecting the option that best accommodates their personal preferences. Decision counseling can be offered by 3 types of providers: clinicians who lack formal informed-choice training ("usual care"), clinicians with formal informed-choice training, or trained third parties who function as impartial decision counselors. Controlled studies are needed to determine which model is best, but none appears to be ideal. The health care system cannot truly support informed decision making without correcting the underlying obstacles that impede patient access to needed information. New information technology solutions, training programs, and reimbursement schemes are necessary. Patient demand for guidance will only increase as clinical options multiply and the world of information continues its rapid growth. Today's health care system is unprepared for the convergence of these 2 burgeoning domains, and the need to address systemic deficiencies will grow more urgent over time. 相似文献
998.
Models of vertebrate skull evolution stress the coordinated developmental relationship between the skull and the brain that it houses. This study investigates the relationship between altered skull morphology and brain morphology in premature fusion of the cranial sagittal suture (isolated sagittal synostosis; ISS), a condition associated with dysmorphology of both neurocranium and brain. Although the skull displays a more normal shape following reconstructive cranial vault surgery, effects of this surgery on the brain have not been investigated. Landmark coordinate data were collected from three-dimensional magnetic resonance imaging reconstructions of the brain in a sample of ISS patients and an age-matched unaffected cohort. These data were analysed using Euclidean distance matrix analysis (EDMA). Results show that the brain in ISS is dysmorphic preoperatively, displaying a posteriorly directed neural expansion that does not 'worsen' with growth. Postoperatively, the brain in ISS displays a more globular shape overall as compared with the preoperative morphology, but differs from normal in its subcortical morphology. These results show that the ISS brain is altered following neurocranial surgery, but does not more closely approximate that of unaffected individuals. This suggests that although the brain is affected by manipulation of the skull, it retains a growth pattern that is, at least in part, independent of the skull. 相似文献
999.
Chacko AD Hyland PL McDade SS Hamilton PW Russell SH Hall PA 《The Journal of pathology》2005,206(4):458-465
Several lines of evidence indicate that altered expression of SEPT9 is seen in human neoplasia. In particular there is evidence of altered expression of the SEPT9_v4 isoform. The functional consequences of this remain unclear. We have studied the expression of wild-type- and GTP-binding mutants (G144V and S148N) of the SEPT9_v4 isoform in the MCF7 cell line as a model for its deregulation in neoplasia. We find that SEPT9_v4 expression induces dramatic actin cytoskeletal reorganization with the formation of processes around the cell periphery. Expression of the SEPT9_v4 isoform and a G144V mutant cause delocalization of endogenous SEPT9 from filamentous structures but the S148N mutant does not have this effect. In addition SEPT9_v4 isoform expression enhances cell motility and is associated with perturbation of directional movement. Expression of SEPT9_v4 GTP binding mutants also has potent effects on morphology and motility and causes loss of normal polarity, as judged by Golgi reorientation assays. The phenotypes induced by expression of the SEPT9_v4 isoform and the GTP mutants provide an insight into possible mechanisms of SEPT9_v4 function and suggest that the GTPase functions have both ras- and rab-like features. We propose a model in which overexpression of the SEPT9_v4 isoform in neoplasia is associated with perturbation of SEPT9 complexes, leading to phenotypes associated with neoplasia. 相似文献
1000.
Vascular dysfunction of venous bypass conduits is mediated by reactive oxygen species in diabetes: role of endothelin-1 总被引:2,自引:0,他引:2
Ergul A Johansen JS Strømhaug C Harris AK Hutchinson J Tawfik A Rahimi A Rhim E Wells B Caldwell RW Anstadt MP 《The Journal of pharmacology and experimental therapeutics》2005,313(1):70-77
Diabetes is associated with increased risk for complications following coronary bypass grafting (CABG) surgery. Augmented superoxide (*O2*) production plays an important role in diabetic complications by causing vascular dysfunction. The potent vasoconstrictor endothelin-1 (ET-1) is also elevated in diabetes and following CABG; however, the effect of ET-1 on *O2* generation and/or vascular dysfunction in bypass conduits remain unknown. Accordingly, this study investigated basal and ET-1-stimulated *O2* production in bypass conduits and determined the effect of *O2* on conduit reactivity. Saphenous vein specimens were obtained from nondiabetic (n = 24) and diabetic (n = 24) patients undergoing CABG. Dihydroethidium staining and NAD(P)H oxidase activity assays (5380 +/- 940 versus 16,362 +/- 2550 relative light units/microg) demonstrated increased basal *O2* levels in the diabetes group (p < 0.05). Plasma ET-1 levels were associated with elevated basal *O2* levels, and treatment of conduits with exogenous ET-1 further increased *O2* production and augmented vasoconstriction. Furthermore, vascular relaxation was impaired in the diabetic group (75 versus 40%), which was restored by *O2* scavenger superoxide dismutase. These findings suggest that ET-1 causes bypass conduits dysfunction via stimulation of *O2* production in diabetes. Novel therapies that attenuate *O2* generation in bypass conduits may improve acute and late outcome of CABG in diabetic patients. 相似文献