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61.
62.
Tiffany M. Newman MD Julie Vasile MD Joshua L. Levine MD David T. Greenspun MD MSc Robert J. Allen MD APMC FACS Minh‐Tam Chao BSRTMR Priscilla A. Winchester MD Martin R. Prince MD PhD 《Journal of magnetic resonance imaging : JMRI》2010,31(5):1176-1184
Purpose
To evaluate the accuracy of magnetic resonance angiography (MRA) for preoperative mapping of rectus and gluteal muscle perforating arteries prior to autologous flap breast reconstruction.Materials and Methods
Preoperative MRA on 25 consecutive patients undergoing perforator artery‐based autologous breast reconstruction was performed at 1.5 T using 3D liver accelerate volume acquisition (LAVA) of abdominal or gluteal regions acquired during injection of 20 mL of gadobenate dimeglumine with bolus timing optimized using MR fluoroscopy or SmartPrep. Perforator artery size and coordinates relative to umbilicus or top of gluteal crease on 3D MRA were compared to findings at surgery. Reconstructed breast volume estimates from MRA were also compared to weights at harvesting.Results
In all, 132 perforator arteries were found at surgery to be located within 1 cm of the coordinates measured on MRA and were surgically verified to be suitable for flap perfusion. Surgery verified the arterial course and caliber through the rectus and gluteal muscles visualized on MRA in 48 of 49 arteries. Volume rendering of 3D MRA predicted a breast reconstruction volume with a mean difference of 47 g compared to measurements at harvesting.Conclusion
MRA accurately maps rectus and gluteal muscle perforator arteries for preoperative planning of autologous flaps for breast reconstruction. J. Magn. Reson. Imaging 2010;31:1176–1184. © 2010 Wiley‐Liss, Inc. 相似文献63.
Using machine learning classifiers to identify glaucomatous change earlier in standard visual fields
Sample PA Goldbaum MH Chan K Boden C Lee TW Vasile C Boehm AG Sejnowski T Johnson CA Weinreb RN 《Investigative ophthalmology & visual science》2002,43(8):2660-2665
PURPOSE: To compare the ability of several machine learning classifiers to predict development of abnormal fields at follow-up in ocular hypertensive (OHT) eyes that had normal visual fields in baseline examination. METHODS: The visual fields of 114 eyes of 114 patients with OHT with four or more visual field tests with standard automated perimetry over three or more years and for whom stereophotographs were available were assessed. The mean (+/-SD) number of visual field tests was 7.89 +/- 3.04. The mean number of years covered (+/-SD) was 5.92 +/- 2.34 (range, 2.81-11.77). Fields were classified as normal or abnormal based on Statpac-like methods (Humphrey Instruments, Dublin, CA) and by several machine learning classifiers. The machine learning classifiers were two types of support vector machine (SVM), a mixture of Gaussian (MoG) classifier, a constrained MoG, and a mixture of generalized Gaussian (MGG). Specificity was set to 96% for all classifiers, using data from 94 normal eyes evaluated longitudinally. Specificity cutoffs required confirmation of abnormality. RESULTS: Thirty-two percent (36/114) of the eyes converted to abnormal fields during follow-up based on the Statpac-like methods. All 36 were identified by at least one machine classifier. In nearly all cases, the machine learning classifiers predicted the confirmed abnormality, on average, 3.92 +/- 0.55 years earlier than traditional Statpac-like methods. CONCLUSIONS: Machine learning classifiers can learn complex patterns and trends in data and adapt to create a decision surface without the constraints imposed by statistical classifiers. This adaptation allowed the machine learning classifiers to identify abnormality in visual field converts much earlier than the traditional methods. 相似文献
64.
Mosulishvili LM Kirkesali EI Belokobylsky AI Khizanishvili AI Frontasyeva MV Pavlov SS Gundorina SF 《Journal of pharmaceutical and biomedical analysis》2002,30(1):87-97
The great potential of using blue-green algae Spirulina platensis as a matrix for the production of selenium- and iodine-containing pharmaceuticals is shown experimentally. The background levels of 31 major, minor and trace elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni (using (n,p) reaction), As, Br, Zn, Rb, Mo, Ag, Sb, I, Ba, Sm, Tb, Tm, Hf, Ta, W, Au, Hg, Th) in S. platensis biomass were determined by means of epithermal neutron activation analysis. The dependence of selenium and iodine accumulation in spirulina biomass on a nutrient medium loading of the above elements was characterized. To demonstrate the possibilities of determining toxic element intake by spirulina biomass, mercury was selected. The technological parameters for production of iodinated treatment-and-prophylactic pills are developed. 相似文献
65.
66.
Extravesical ureterocystoanastomosis without wide opening of the urinary bladder was practised since 1986. A total of 79 patients were operated: 71 children at the age from 1 to 14 years and 8 adults aged 14 to 58 years. Surgical intervention was performed on 112 ureters for vesicoureteral reflux and supravesical ureteral obstruction. 6 of 79(7.6%) patients on postoperative day 11-15 after removal of intubating drains had an attack of acute pyelonephritis. 3 of these 6 patients were reoperated with a good effect, in 2 patients urine passage recovered 2-3 months after removal of transcutaneous puncture nephrostoma. In one child this technique was used for the first time at the third operation on vesicoureteral anastomosis. This prevented subsequent removal of the nephrostomic drain because of vesicoureteral reflux in the presence of severe irreversible retention changes of both ureters. The advantages of the above technique are reduced operative injury, no contraindications in primary operations and reoperations, feasibility in various forms of vesicoureteral anastomosis failure. This makes the technique of extravesical ureterocystoanastomosis rather promising. 相似文献
67.
Unraveling the nanostructure of supramolecular assemblies of hydrogen-bonded rosettes on graphite: an atomic force microscopy study 下载免费PDF全文
Schönherr H Paraschiv V Zapotoczny S Crego-Calama M Timmerman P Frank CW Vancso GJ Reinhoudt DN 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(8):5024-5027
The self-organization of multicomponent tetrarosette assemblies into ordered nanostructures on graphite surfaces has been studied by atomic force microscopy (AFM). Real-space information on the level of individual molecules allowed us to analyze the underlying structure in unprecedented detail. In highly ordered nanorod domains, tetrarosettes 1(3) x (DEB)(12) arrange in the form of parallel rows with a spacing of 4.6 +/- 0.1 nm. High resolution AFM revealed the internal packing of the tetrarosette assemblies in these rows, which can be described by an oblique lattice with a = 2.5 +/- 0.3 nm, b = 5.0 +/- 0.1 nm, and gamma = 122 +/- 3 degrees. The results, together with recent improvements in synthetic approaches, contribute to the development of a general strategy to develop H-bonding-based nanostructures with molecular precision. 相似文献
68.
The purpose of this study was to describe isolated injury of the cuboid bone as a potentially radiographically occult cause
of foot pain. The imaging studies of 17 patients, 13 women and 4 men aged 17–79 years (average 45 years), who presented with
pain over the lateral aspect of the midfoot were retrospectively reviewed. Frontal, lateral, and inversion-oblique radiographs
were available for all patients. In addition, MR imaging was performed in eight patients, CT in two, conventional tomography
in two, and bone scan in one. Conventional radiographs revealed cuboid fracture in seven patients. Of the remaining ten, eight
underwent MR imaging which demonstrated four fractures, three bone bruises, and one stress reaction, and two had tomography,
CT, and/or bone scan, all of which documented an isolated cuboid fracture. Isolated fracture of the cuboid may be radiographically
occult. Other imaging modalities, particularly MR imaging, can document this injury as the source of pain.
Electronic Publication 相似文献
69.
Results of surgical treatment of 20 patients with malignant lung tumors operated in N.N.Burdenko faculty surgical clinic were analyzed. The authors have developed the method of prophylaxis of acute postoperative pleural empyemas patented in Russian Federation. This method is: after main stage of operation (lob- or pneumonectomy) pleural cavity in filled with antiseptic solutions (furacillin 1:5000, 0.02% chlorgexidin). 5 ml of photosense (sulfured ftalocyanin of aluminium) were injected in pleural cavity, after it pleural cavity is treated by low-frequency ultrasound. After it the antiseptic is removed and pleural cavity is irradiated by red light with use of KAMIN-VIDEO lamp. In all the 20 operated patients who had undergone sanation of pleural cavity by low-frequency ultrasound and it irradiation by KAMIN-VIDEO lamp the postoperative period was uncomplicated. 相似文献