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81.
ABSTRACT:: Centromedullary pinning provides an excellent alternative to open reduction in severely displaced radial neck fractures. It has a low complication rate because it is an extra-articular and minimally invasive technique. The functional results have been shown to be good or excellent in most cases. The technique is described clearly in the literature but has posed us with certain difficulties. We present a useful technical tip on performing centromedullary pinning based on our experience of treating radial neck fractures by this method. 相似文献
82.
An iodinated (125I/127I) ethidium derivative (3,8-diamino-5-[6′-(p-iodobenzoylamino)-4′-azahexyl]-6-phenylphenanthridinium chloride hydrochloride) was synthesized and characterized. The labeling yield of the 125I-labeled derivative was 75% for carrier-free 125I, with a radiochemical purity of 95%. The incubation of iodoethidium with calf thymus DNA resulted in a substantial enhancement of fluorescence yield, indicating the intercalation of this compound into DNA. In the presence of iodoethidium, the nuclei of methanol-treated mammalian cells fluoresced, while those of viable cells did not (since the plasma membrane is impermeable to iodoethidium). When viable cells were incubated with the reduced form of the derivative, 125I/127I-dihydroethidium traversed the plasma membrane, was oxidized in the cytoplasm, and intercalated into nuclear DNA. Finally, we tested the hypothesis that larger malignant solid tumors, containing a relatively greater percentage of degenerating permeable cells, can be targeted with 125I-ethidium. In-vivo studies demonstrated a small but positive correlation (R = 0.72) between tumor volume and the uptake of the derivative. Because of the ubiquitous presence of abnormal permeable cells and necrosis in tumors, our results support the belief that radiolabeled DNA-intercalating or DNA-binding molecules may be of diagnostic and therapeutic value for a variety of solid tumors in humans. 相似文献
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84.
Natural Convection Heat Transfer in a Porous Cavity with Sinusoidal Temperature Distribution Using Cu/Water Nanofluid: Double MRT Lattice Boltzmann Method 下载免费PDF全文
Hasan Sajjadi Amin Amiri Delouei Rasul Mohebbi Mohsen Izadi & Sauro Succi 《Communications In Computational Physics》2021,29(1):292-318
In this study, natural convection flow in a porous cavity with sinusoidal
temperature distribution has been analyzed by a new double multi relaxation time
(MRT) Lattice Boltzmann method (LBM). We consider a copper/water nanofluid filling a porous cavity. For simulating the temperature and flow fields, D2Q5 and D2Q9
lattices are utilized respectively, and the effects of different Darcy numbers (Da) (0.001-0.1) and various Rayleigh numbers (Ra) ($10^3$-$10^5$) for porosity ($ε$) between 0.4 and 0.9
have been considered. Phase deviation ($θ$) changed from 0 to $π$ and the volume fraction
of nanoparticles (Ø) varied from 0 to 6%. The present results show a good agreement
with the previous works, thus confirming the reliability the new numerical method
proposed in this paper. It is indicated that the heat transfer rate increases at increasing
Darcy number, porosity, Rayleigh number, the volume fraction of nanoparticles and
phase deviation. However, the most sensitive parameter is the Rayleigh number. The
maximum Nusselt deviation is 10%, 32% and 33% for Ra=$10^3$, $10^4$ and $10^5$, respectively, with $ε = 0.4$ to $ε = 0.9$. It can be concluded that the effect of Darcy number on
the heat transfer rate increases at increasing Rayleigh number, yielding a maximum
enhancement of the average Nusselt number around 12% and 61% for Ra=$10^3$ and
Ra=$10^5$, respectively. 相似文献
85.
Paul D. Kim M.D. Austin Hayes M.D. Faiq Amin M.D. Yelena Akelina D.V.M. Arthur P. Hays M.D. Melvin P. Rosenwasser M.D. 《Microsurgery》2010,30(5):392-396
Peripheral nerve repair is often complicated by fibroblastic scar formation, nerve dysfunction, and traumatic neuroma formation. Use of bio‐absorbable protective wraps may improve outcomes of these repairs. This study histologically compared the incidence of neuroma formation, connective tissue proliferation, and axonal regrowth in transected rat sciatic nerves repaired with and without tubular collagen nerve sleeves. Twenty Sprague‐Dawley rats underwent unilateral sharp sciatic nerve transection and microscopic nerve repair with four epineural sutures and were randomly treated with or without an encircling collagen nerve sleeve. Normal nerves from the contralateral sciatic nerve were also examined. At sacrifice three months later, the nerves were evaluated for traumatic neuroma formation, perineural scar formation, and morphometric analysis. Histological examination of normal and repaired nerves by a neuropathologist demonstrated healing, minimal Wallerian degeneration and no traumatic neuroma formation. Distal section analysis (nine nonwrapped, 10 wrapped), revealed no significant differences in total fascicular area, myelinated fibers per nerve, fiber density, myelin area per nerve, myelinated fiber diameter, axon diameter, myelin thickness, or G‐ratio. Significantly greater (P = 0.005) inner epineural connective tissue formation was observed in nonwrapped nerves (0.62 mm2 ± 0.2) versus wrapped nerves (0.35 mm2 ± 0.16). The ratio of connective tissue to fascicular area was larger in nonwrapped (1.08 ± 0.26) versus wrapped nerves (0.63 ± 0.22) (P < 0.001). This study demonstrated decreased inner epineural connective tissue formation with use of a collagen nerve wrap during primary repair of peripheral nerve transection in a rat sciatic nerve model. © 2010 Wiley‐Liss, Inc. Microsurgery 30:392–396, 2010. 相似文献
86.
Saurabh Sharma Vijay Kumar Mamta Sood Rajesh Malhotra 《Indian Journal of Orthopaedics》2021,55(4):939
BackgroundNon-surgical factors have been found to have significant impact on outcome following Total Knee Arthroplasty (TKA). The study was conducted to know the independent effect of each of the four interacting psychological factors: anxiety, depression, pain catastrophizing and kinesiophobia on early outcome following TKA in an Indian population.Materials and Methods104 consecutive patients undergoing TKA were included in the study and followed up at 6 weeks, 6 months and one year. Preoperatively, Hospital Anxiety and Depression Scale was used to diagnose and quantify anxiety and depression, pain catastrophizing and kinesiophobia were assessed using Pain Catastrophizing Scale and Tampa Scale for Kinesiophobia, respectively. Outcome was assessed on the basis of Knee Society Score and Knee Injury and Osteoarthritis Outcome Score. Regression analysis was done to know independent effect of each factor on outcome scores.ResultsNine (8.7%) patients were found to have undiagnosed psychopathology. The patients with psychopathologies were found to have significantly worse knee outcome scores on follow-up, although the rate of improvement in knee symptoms and function was not significantly different from those without psychopathology. The degree of Anxiety correlated with worse knee pain and stiffness up to 6 months while it correlated with poor knee function for a longer duration. The degree of depression and pain catastrophizing correlated with worse knee pain, stiffness and function at all visits while kinesiophobia didn’t show correlation independent other factors.ConclusionPsychopathology was found to be associated poor knee outcome scores with degree of preoperative depression and pain catastrophizing as significant independent predictors as poor outcome, whereas the effect of degree of anxiety on knee pain and stiffness was found to wane over time. Kinesiophobia didn’t show any independent correlation.Supplementary InformationThe online version of this article (10.1007/s43465-020-00325-x) contains supplementary material, which is available to authorized users. 相似文献
87.
88.
David Christen L Joseph Melton III Alexander Zwahlen Shreyasee Amin Sundeep Khosla Ralph Müller 《Journal of bone and mineral research》2013,28(12):2601-2608
More accurate techniques to estimate fracture risk could help reduce the burden of fractures in postmenopausal women. Although micro‐finite element (µFE) simulations allow a direct assessment of bone mechanical performance, in this first clinical study we investigated whether the additional information obtained using geometrically and materially nonlinear µFE simulations allows a better discrimination between fracture cases and controls. We used patient data and high‐resolution peripheral quantitative computed tomography (HRpQCT) measurements from our previous clinical study on fracture risk, which compared 100 postmenopausal women with a distal forearm fracture to 105 controls. Analyzing these data with the nonlinear µFE simulations, the odds ratio (OR) for the factor‐of‐risk (yield load divided by the expected fall load) was marginally higher (1.99; 95% confidence interval [CI], 1.41–2.77) than for the factor‐of‐risk computed from linear µFE (1.89; 95% CI, 1.37–2.69). The yield load and the energy absorbed up to the yield point as computed from nonlinear µFE were highly correlated with the initial stiffness (R2 = 0.97 and 0.94, respectively) and could therefore be derived from linear simulations with little loss in precision. However, yield deformation was not related to any other measurement performed and was itself a good predictor of fracture risk (OR, 1.89; 95% CI, 1.39–2.63). Moreover, a combined risk score integrating information on relative bone strength (yield load‐based factor‐of‐risk), bone ductility (yield deformation), and the structural integrity of the bone under critical loads (cortical plastic volume) improved the separation of cases and controls by one‐third (OR, 2.66; 95% CI, 1.84–4.02). We therefore conclude that nonlinear µFE simulations provide important additional information on the risk of distal forearm fractures not accessible from linear µFE nor from other techniques assessing bone microstructure, density, or mass. © 2013 American Society for Bone and Mineral Research. 相似文献
89.
Amin Kalaaji Jan Lilja Anna Elander Hans Friede 《Journal of plastic surgery and hand surgery》2013,47(1):35-42
Tibial bone grafts were studied in 137 patients with clefts of the lip and palate. Twenty-one had clefts of the lip and primary palate and 116 had complete unilateral clefts of the lip and palate. Bone grafting was performed secondarily or late secondarily. Bone was harvested from the proximal part of the tibia distal to the tuberosity through an incision about 15 mm long. The mean follow-up time after bone grafting was 5.5 years (range 2-11). There were no operative, or early or late postoperative complications reported (such as haematoma, fracture, or shortening of the limb). Harvesting time was about 15 minutes. The possibility of operating with two teams makes the total operating time shorter. Bleeding was negligible (less than 15 ml) and the amount of bone obtained was always sufficient. Patients were mobilised the next day and were back to full physical activity by one month. Indications for tibial bone grafting included facilitation of tooth eruption into the graft, giving bony support to the neighbouring teeth, making it possible to insert a titanium fixture, raising the alar base of the nose, and closing an oronasal fistula. Compared with iliac, cranial, mandibular, and costal donor sites, using the tibia took less time, gave less bleeding, made it possible for two teams to operate simultaneously, gave a smaller scar, and there were minimal complications and satisfactory quantity and quality of bone in all cases. The results suggested that the tibia is an excellent choice of graft for residual alveolar clefts in patients with cleft lip and palate. 相似文献
90.
Aim:To evaluate the protective effects of Hibiscus sabdariffa(Roselle)and Zingiber officinale(Ginger)againstcisplatin-induced reproductive toxicity in rats and to study the mechanisms underlying these effects.Methods:Ethanol extracts of H.sabdariffa or Z.o fficinale[1g/(kg.day)]were given p.o.to male albino rats for 26 days,which began 21 days before a single cisplatin i.p.injection(10 mg/kg body weight).Results:Extracts of H.sabdariffaand Z.officinale reduced the extent of cisplatin-induced sperm abnormality and enhanced sperm motility.Bothextracts restored the control level of malondialdehyde(MDA)(lipid peroxidation marker)in the cisplatin-treated testis.The cisplatin injection induced decline in the levels of superoxide dismutase(SOD),reduced glutathione(GSH)andcatalase(CAT)were significantly reversed to control levels in groups where cisplatin was preceded by the administra-tion of either H.sabdariffa or Z.officinale.Conclusion:Both H.sabdariffa and Z.officinale treatment increasedthe activities of testicular antioxidant enzymes and restored sperm motility of cisplatin-treated rats.The protectiveeffects of tested plants are,therefore,suggested to be mediated by their potent antioxidant activities.(Asian J Androl2006 Sep;8:607-612) 相似文献