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排序方式: 共有1214条查询结果,搜索用时 15 毫秒
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Qiaojie Wang Karan Goswami Noam Shohat Arash Aalirezaie Jorge Manrique Javad Parvizi 《The Journal of arthroplasty》2019,34(5):947-953
Background
Whether prolonged operative time is an independent risk factor for subsequent surgical site infection (SSI) and periprosthetic joint infection (PJI) following total joint arthroplasty (TJA) remains a clinically significant and underexplored issue. The aim of this study is to investigate the association between operative time and the risk of subsequent SSI and PJI in patients undergoing primary TJA.Methods
We retrospectively reviewed 17,342 primary unilateral total knee arthroplasty and total hip arthroplasty performed at a single institution between 2005 and 2016, with a minimum follow-up of 1 year. A multivariate logistic regression model was conducted to identify the association between operative time and the development of SSI within 90 days and PJI within 1 year.Results
Overall, the incidence of 90-day SSI and 1-year PJI was 1.2% and 0.8%, respectively. Patients with an operative time of >90 minutes had a significantly higher incidence of SSI and PJI (2.1% and 1.4%, respectively) compared to cases lasting between 60 and 90 minutes (1.1% and 0.7%), and those lasting ≤60 minutes (0.9% and 0.7%, P < .01). In the multivariate model, the risk for infection increased by an odds ratio of 1.346 (95% confidential interval 1.114-1.627) for 90-day SSI and 1.253 (95% confidential interval 1.060-1.481) for 1-year PJI for each 20-minute increase in operative time.Conclusion
In patients undergoing primary TJA, each 20-minute increase in operative time was associated with nearly a 25% increased risk of subsequent PJI. We advocate that surgeons pay close attention to this underappreciated risk factor while maintaining safe operative practices, which minimize unnecessary steps and wasted time in the operating room. 相似文献3.
Granat Nadav Klang Eyal Tau Noam Kleinbaum Yeruham 《The American journal of emergency medicine》2019,37(10):1823-1828
ObjectiveTo evaluate the significance of sonographic perinephric fluid collection on the emergent management of patients with acute urinary stone obstruction.MethodsWe conducted a prospective study with retrospective analysis. Since January 2016 through July 2017, patients admitted to our tertiary hospital's emergency department (ED) with suspected symptomatic urinary stones underwent ultrasound evaluation. Images were prospectively interpreted by experienced radiologist who analyzed each case for the following imaging features: hydronephrosis, perinephric fluid and urethral stone identification. The presence and measurements of perinephric fluid were re-evaluated by second radiologist who was blinded for the first reader's measurements. Retrospective analysis was conducted to evaluate for an association between perinephric fluid collection and the following outcome variables: need for analgesics, the number of doses of analgesics and the amount of morphine (mg) in the ED, elevation of creatinine levels, hospitalization and need for urological interventions.ResultsThe need for analgesics, the number of doses of analgesics and the amount of morphine were significantly associated with the presence of perinephric fluid (p < 0.05). The odds ratio for the need for analgesics was 3.8 in the presence of any perinephric fluid, and 8.9 in the presence of moderate/severe perinephric fluid. No other patient outcome variables were found to be significantly associated with the presence of perinephric fluid (p > 0.05).ConclusionsThis study shows a correlation between sonographic evidence of perinephric fluid and more severe pain. Therefore, an emergency physician can consider the evidence of perinephric fluid, in acute urethral stone obstruction, a predictor for more severe pain. 相似文献
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At present the pathogenesis of diabetic nephropathy remains unresolved. Clearly lack of insulin, with its associated disorders of carbohydrate, protein, and/or lipid metabolism, initiates the process which eventually leads to the characteristic histologic picture of diabetic nephropathy. The disturbance in cellular metabolism per se could directly injure the kidney by altering the energy needs of the cell or by leading to the accumulation of cellular toxins (ie, polyols) or by causing the deficiency of key cellular metabolites (ie, myoinositol). Elevation of the plasma glucose concentration enhances the glycosylation of proteins, which in turn can lead to glomerular basement membrane thickening, loss of charge selectivity, and direct cellular damage. The multiple disturbances in intermediary metabolism are associated with increased levels of and/or enhanced sensitivity to a variety of growth factors, including IGF-I and angiotensin, and this could lead to glomerular hypertrophy. An increase in the filtered load and subsequent reabsorption of electrolytes and metabolites also could contribute to renal hypertrophy. In all animal models of nephropathy, including diabetes, glomerular hypertrophy has been shown to be the best correlate of glomerular sclerosis, proteinuria, and progressive renal deterioration. The potential mechanisms by which glomerular hypertrophy can lead to renal histologic damage were discussed previously. By increasing the luminal diameter, glomerular hypertrophy also would be expected to augment wall tension and thereby increase intraglomerular pressure. Derangements in cellular metabolism or altered sensitivity to angiotensin also can directly elevate the intraglomerular pressure and lead to structural renal damage. In this schema, elevated intraglomerular pressure is but one of many pathogenic factors that contribute to the development of diabetic glomerulopathy and albuminuria. The precise role of increased glomerular pressure in the evolution of diabetic nephropathy remains uncertain at present. In rats, severe diabetic nephropathy can occur without an increase in Pgc, while in humans, hyperfiltration does not appear to be a predictor of proteinuria and renal dysfunction. Lastly, it is likely that a variety of other factors, including the coagulation system, plasma/cell lipid levels, prostaglandins, etc, also play a role in the pathogenesis of diabetic nephropathy. According to the outline presented in Figure 1, it is unlikely that any single factor will be sufficient to explain the development of diabetic glomerulosclerosis. Ultimately, the origin of diabetic nephropathy in IDDM must be traced to insulin lack, with its associated derangements in cellular metabolism. Therefore, the importance of tight glucose control should not be underemphasized.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
5.
We report vertical transmission of isolated congenital vertical talus through three generations of a Honduran family. Five of nine affected family members were examined and the diagnosis was confirmed radiographically. There was incomplete penetrance in one clinically unaffected woman with two affected children. Bilateral and unilateral involvement was seen with a wide range of severity. Based on this family and on cases reviewed from the literature, we propose that isolated congenital vertical talus can be inherited as an autosomal dominant trait with variable expression and incomplete penetrance. 相似文献
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The effects of anesthesia on otoacoustic emissions 总被引:4,自引:0,他引:4
Noam Harel Akinobu Kakigi Haruo Hirakawa Richard J. Mount Robert V. Harrison 《Hearing research》1997,110(1-2):25-33
We have measured transient-evoked and distortion-product otoacoustic emissions (OAEs) in the chinchilla and compared them in the awake and anesthetized animal (using either ketamine or barbiturate agents). We report a significant increase in OAE amplitudes during anesthesia, particularly using ketamine. These effects are most evident for transient-evoked otoacoustic emissions (TEOAEs) as measured in the non-linear mode. Our data support the hypothesis that tonic activity levels in cochlear efferents may be reduced by anesthetic effects, either directly or indirectly (e.g., by general reductions in descending pathway activity), and that reduced cochlear efferent activity will result in the observed increase of OAE amplitudes. 相似文献
9.
Bensafi M Porter J Pouliot S Mainland J Johnson B Zelano C Young N Bremner E Aframian D Khan R Sobel N 《Nature neuroscience》2003,6(11):1142-1144
Neural representations created in the absence of external sensory stimuli are referred to as imagery, and such representations may be augmented by reenactment of sensorimotor processes. We measured nasal airflow in human subjects while they imagined sights, sounds and smells, and only during olfactory imagery did subjects spontaneously enact the motor component of olfaction--that is, they sniffed. Moreover, as in perception, imagery of pleasant odors involved larger sniffs than imagery of unpleasant odors, suggesting that the act of sniffing has a functional role in creating of olfactory percepts. 相似文献
10.
Lymphocyte activation: IV. The ultrastructural pattern of the response of mouse T and B cells to mitogenic stimulation in vitro 总被引:8,自引:0,他引:8 下载免费PDF全文
Thymocytes from cortisone-treated mice (`T' cells), `B' spleen cells (B lymphocytes from thymectomized, irradiated, marrow reconstituted mice) and normal spleen (T + B) cells were examined by electron microscopy after 60 hours stimulation by Concanavalin A (a T cell specific mitogen), endotoxin (B cell specific mitogen), and pokeweed mitogen (which stimulates both T and B cells). Stimulation of T cells by Con A or PWM induced the appearance of lymphoblasts (Type I) and only PWM or endotoxin stimulated B cells developed `plasmablast' features (dilated, vesicular rough endoplasmic reticulum; Type II). A few stimulated B cells also had lymphoblast morphology. Large cells from normal (T + B) spleen stimulated by PWM were heterogeneous consisting of 55–60 per cent plasmablasts and 40–45 per cent lymphoblasts. It was concluded that the ultrastructure of stimulated lymphocytes depended on whether T or B cells were stimulated and not primarily on the mitogen used. In general, the response evoked by mitogens paralleled at the ultrastructural level that induced by antigens. It was also found that multivesicular bodies and glycogen particles occurred predominantly in the cytoplasm of stimulated T cells (lymphoblasts). 相似文献