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61.
Kevin P. Feltz Nicklaus Hanson Nathan J. Jacobson Paul A. Thompson Geoffrey F. Haft 《The Iowa orthopaedic journal》2022,42(1):53
BackgroundLength of stay (LOS) in the hospital following posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS) has decreased over the past decade due to well-defined postoperative clinical pathways, earlier mobilization, and improved pain control methods. Historically, liberal use of parenteral and oral opioids for pain control caused side effects, resulting in delayed discharge. Intraoperative intrathecal morphine (ITM) has been posited to reduce the need for postoperative opioids and to expedite the discharge process. This study examines the relationship between the use of ITM with average required postoperative opioid usage and with average LOS.MethodsThis IRB-approved retrospective cohort study examined 105 patients with AIS who received PSF with instrumentation split into two cohorts. One cohort underwent PSF via standard surgical protocol (n=40) while the other cohort received intraoperative ITM with the standard surgical protocol (n=65). Power analysis demonstrated a study power of 0.8. LOS and total postoperative opioid analgesic medication (morphine milligram equivalent, MME) data were collected. Age at surgery, gender, number of spinal levels fused, estimated intraoperative blood loss (EBL), preoperative Cobb angle, and any complications related to the use of ITM were also recorded. Continuous variables were analyzed with Student’s t-test and categorical variables were analyzed with chi-square independent-sample tests using SAS 9.4 (α = 0.05).ResultsPatients who were treated with ITM displayed shorter LOS (p<0.0001) and reduced postoperative analgesic requirement (p<0.0001). Patients who received ITM spent an average of 1.8 fewer midnights in the hospital and received an average of 221.2 MME less than patients who received standard protocol (57% decrease). There were no significant differences between the two groups for any other variable.ConclusionIntraoperative ITM is a simple and effective treatment for scoliosis surgeons to better control postoperative pain in patients, reduce the risk of dependency, and achieve earlier discharge from the hospital. Shortened LOS reduces the overall cost of care, benefitting patients, hospitals, and insurance companies. Based on the results of this study and several earlier studies, the authors recommended that scoliosis surgeons consider incorporating use of ITM into their standard operative protocols. Level of Evidence: IV 相似文献
62.
Based on the pathological processes involved in rheumatoid spondylitis, comparison is made between the physical qualities of certain techniques of roentgen therapy. Graphic representation of the isodose curves and the homogeneous distribution of radiation pertaining to the method herein advocated is shown.Results obtained in the treatment of 125 cases illustrative of the evolution of technique experienced at the University of California Hospital are tabulated. The indications, contraindications, and complications of the method are discussed.Practically every patient with rheumatoid spondylitis, regardless of the stage of the disease, was benefited, with the best results having been obtained when the radiation was given in three courses, separated by rest periods, and homogeneously distributed along the spine. 相似文献
63.
64.
Nathan W. Shock 《The Journal of general physiology》1944,27(3):143-154
The rate at which displacement and recovery of the acid-base equilibrium of the blood occur in young adult males subjected to short periods of maximal exertion has been determined. Displacement of acid-base equilibrium produced by severe exercise is along the fixed acid path, similar to the path of displacement produced by ingestion of acidifying agents such as ammonium chloride. Maximum displacement of the acid-base equilibrium is not reached until 7 to 10 minutes after the cessation of exercise. By this time over 50 per cent of the displacement in oxygen consumption, respiratory volume, and blood pressure have disappeared. A much greater metabolic acidosis was produced by exercise than could be induced by the oral administration of ammonium chloride. Recovery from the metabolic acidosis produced by exercise was much more rapid (10 times) than was recovery from the acidosis produced by ammonium chloride. After exercise the pH, returned to normal values more rapidly than did the bicarbonate content of the serum. 相似文献
65.
A simple theoretical model has been presented whose behavior duplicates the variation in bicarbonate ion concentration in the blood following exercise. Methods for the evaluation of the constants of rational equations to describe the concentration in muscle cells, in blood plasma, and in removal cells, of the anions produced in exercise have been devised. These methods have been applied to experimental data from 23 experiments, and a close agreement between the observed and theoretically predicted values for blood plasma has been found. From the mathematical analysis of the data values for permeability of acid anions produced in exercise have been estimated as 75 x 10–5 and 5.9 x 10–5 cm. per sec. between muscle cell and blood (extracellular fluid) and between blood plasma and removal cells respectively. 相似文献
66.
A dye mixture, consisting of a celestine blue B dispersion (prepared according to Gray et al. 1956), orange G, and acid fuchsin in one solution, simultaneously stains nuclear elements and gives double contrast staining of cytoplasmic elements. Orange G, 0.16 gm, and acid fuchsin, 0.04 gm, dissolved in 100 ml of celestine blue B dispersion and adjusted to pH 0.8 gives, when applied for 1.5 min, results comparable or superior to other “triple contrast” stains on a wide variety of tissues. No differentiation other than that which occurs during dehydration is necessary. 相似文献
67.
68.
Muchhala N 《Oecologia》2003,134(3):373-380
In this study I documented the degree of specialization in the pollination systems of Burmeistera cyclostigmata and B. tenuiflora (Campanulaceae) to explore the potential role of floral isolation in the diversification of the genus. I asked which floral characteristics are important in specializing on either bat or hummingbird pollination, and whether overlap between these floral syndromes can exist. I examined nocturnal and diurnal pollen deposition, pollinator visitation rates, and single visit effectiveness and related them to intra- and interspecific variation in Burmeistera floral characteristics at Monteverde, Costa Rica. Bats and hummingbirds visited both Burmeistera species, and bats pollinated both species. Owing to differences in floral morphology, however, hummingbirds effectively pollinated only B. tenuiflora. The generalized pollination system of B. tenuiflora demonstrates that there can be overlap in the boundary between ornithophily and chiropterophily, and that nectar production and timing of anthesis do not serve as barriers between these syndromes. The high intraspecific variation in floral color from green to red or purple did not correlate with either nocturnal or diurnal pollen deposition. Degree of flower accessibility did affect pollination; nocturnal pollen deposition significantly decreased as flowers become more obstructed. In Burmeistera, floral morphology and accessibility appear to be the most important floral characteristics for specialization at the boundary between ornithophily and chiropterophily. 相似文献
69.
Genomewide association study for susceptibility genes contributing to familial Parkinson disease 总被引:1,自引:0,他引:1
Pankratz N Wilk JB Latourelle JC DeStefano AL Halter C Pugh EW Doheny KF Gusella JF Nichols WC Foroud T Myers RH;PSG-PROGENI GenePD Investigators Coordinators Molecular Genetic Laboratories 《Human genetics》2009,124(6):593-605
Five genes have been identified that contribute to Mendelian forms of Parkinson disease (PD); however, mutations have been
found in fewer than 5% of patients, suggesting that additional genes contribute to disease risk. Unlike previous studies that
focused primarily on sporadic PD, we have performed the first genomewide association study (GWAS) in familial PD. Genotyping
was performed with the Illumina HumanCNV370Duo array in 857 familial PD cases and 867 controls. A logistic model was employed
to test for association under additive and recessive modes of inheritance after adjusting for gender and age. No result met
genomewide significance based on a conservative Bonferroni correction. The strongest association result was with SNPs in the
GAK/DGKQ region on chromosome 4 (additive model: p = 3.4 × 10−6; OR = 1.69). Consistent evidence of association was also observed to the chromosomal regions containing SNCA (additive model: p = 5.5 × 10−5; OR = 1.35) and MAPT (recessive model: p = 2.0 × 10−5; OR = 0.56). Both of these genes have been implicated previously in PD susceptibility; however, neither was identified in
previous GWAS studies of PD. Meta-analysis was performed using data from a previous case–control GWAS, and yielded improved
p values for several regions, including GAK/DGKQ (additive model: p = 2.5 × 10−7) and the MAPT region (recessive model: p = 9.8 × 10−6; additive model: p = 4.8 × 10−5). These data suggest the identification of new susceptibility alleles for PD in the GAK/DGKQ region, and also provide further support for the role of SNCA and MAPT in PD susceptibility.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
N. Pankratz and J. B. Wilk are joint first authors. 相似文献
70.
Temperature, but not productivity or geometry, predicts elevational diversity gradients in ants across spatial grains 总被引:2,自引:0,他引:2
Nathan J. Sanders Jean-Philippe Lessard Matthew C. Fitzpatrick Robert R. Dunn 《Global Ecology and Biogeography》2007,16(5):640-649
Aim This research aims to understand the factors that shape elevational diversity gradients and how those factors vary with spatial grain. Specifically, we test the predictions of the species–productivity hypothesis, species–temperature hypothesis, the metabolic theory of ecology and the mid-domain effects null model. We also examine how the effects of productivity and temperature on richness depend on spatial grain.
Location Deciduous forests along an elevational gradient in Great Smoky Mountains National Park, USA.
Methods We sampled 22 leaf litter ant assemblages at three spatial grains, from 1-m2 quadrats to 50 × 50 m plots using Winkler samplers.
Results Across spatial grains, warmer sites had more species than did cooler sites, and primary productivity did not predict ant species richness. We found some support for the predictions of the metabolic theory of ecology, but no support for the mid-domain effects null model. Thus, our data are best explained by some version of a species–temperature hypothesis.
Main conclusions Our results suggest that temperature indirectly affects ant species diversity across spatial grains, perhaps by limiting access to resources. Warmer sites support more species because they support more individuals, thereby reducing the probability of local extinction. Many of our results from this elevational gradient agree with studies at more global scales, suggesting that some mechanisms shaping ant diversity gradients are common across scales. 相似文献
Location Deciduous forests along an elevational gradient in Great Smoky Mountains National Park, USA.
Methods We sampled 22 leaf litter ant assemblages at three spatial grains, from 1-m
Results Across spatial grains, warmer sites had more species than did cooler sites, and primary productivity did not predict ant species richness. We found some support for the predictions of the metabolic theory of ecology, but no support for the mid-domain effects null model. Thus, our data are best explained by some version of a species–temperature hypothesis.
Main conclusions Our results suggest that temperature indirectly affects ant species diversity across spatial grains, perhaps by limiting access to resources. Warmer sites support more species because they support more individuals, thereby reducing the probability of local extinction. Many of our results from this elevational gradient agree with studies at more global scales, suggesting that some mechanisms shaping ant diversity gradients are common across scales. 相似文献