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11.
OBJECTIVE: The purpose of this study was to determine whether global statistical data from radionuclide ventilation-perfusion scans could predict the likelihood of pulmonary embolism. MATERIALS AND METHODS: Digital data were obtained from 161 patients undergoing both radionuclide ventilation-perfusion scanning and subsequent pulmonary angiography. Morphometric data characterizing whole-lung perfusion and ventilation parameters were input into artificial neural networks in an attempt to predict the likelihood of pulmonary embolism. RESULTS: The performance of artificial neural networks using only automated global region of interest-based data was superior to that of clinicians in predicting the likelihood of acute pulmonary embolism in patients with normal findings on chest radiographs with segmental or larger emboli (p < .005) and in patients with normal findings on chest radiographs and emboli of any size (p < .01). Network performance did not significantly differ from clinician performance in patients with abnormal findings on chest radiographs. CONCLUSION: The adjunctive use of artificial neural networks using only user-independent, standard image statistics can significantly improve accuracy in the diagnosis of pulmonary embolism in patients with normal findings on chest radiographs. 相似文献
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Ríos A Martínez-Alarcón L López-Navas A Sánchez J Guzmán D Febrero B Ramis G Ramírez P Parrilla P 《Transplantation proceedings》2011,43(3):692-694
Introduction
The concept of brain death (BD) is not well understood among the general public, rendering it one of the main psychosocial barriers to favorable attitudes toward donation. Individuals from the British Isles are among the most important migratory groups in southeastern Spain. We sought to analyze the level of understanding of the concept of brain death among the British and Irish populations living in southeastern Spain, and to determine factors affecting their attitudes.Material and Method
A random sample of the British and Irish population resident in Murcia was stratified according to nationality as part of the “International Collaborative Donor Program” (n = 1611). The self-administered survey in English was completed anonymously. For the statistical analysis, we used the χ2 test and a logistical regression analysis.Results
Approximately half of the respondents (45%; n = 692) understood the concept of BD; they considered it to mean the death of an individual. Among of the other respondents, 39% (n = 605) did not understand this concept, and the remaining 16% (n = 240) erroneously believed that it did not imply a person's death. Respondents coming from Great Britain showed a greater knowledge of the BD concept than did the Irish (46% vs 34%; P < .001). Those who understood the concept of BD were more in favor of deceased donation than those who had an erroneous understanding (49% vs 36%; P < .001). Significant associations were also noted among variables directly or indirectly related to donation and transplantation (P < .05).Conclusion
The level of understanding of the concept of BD among the population from the British Isles resident in southeastern Spain was limited. Taking into account that the BD concept is a psychosocial factor that affects attitudes toward organ donation, information campaigns should be applied to this emerging population group in southeastern Spain. 相似文献15.
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Francisco Sánchez-De Pedro Carlos Moreno-Sanz Antonio Morandeira-Rivas Jose María Tenías-Burillo Cristina Alhambra-Rodríguez De Guzmán 《Surgical endoscopy》2014,28(2):508-514
Background
Recently, there has been speculation about the possibility of fusing intestinal tissue using bipolar sealing devices. In this study we compare in a porcine model the anastomoses created using the LigaSure® device with those created with a stapler after section and closure of a rectal stump.Methods
Thirty pigs underwent laparoscopic colorectal anastomosis. In group A (n = 15), the division of the intestine and distal stump closure were done with a 10-mm LigaSure Atlas® device. In group B, these steps were carried out using an endoscopic stapler. Subsequently, the colorectal anastomosis was performed using circular stapling in both groups. The 4-week follow-up included health status, weight gain, blood tests, X-rays, and colonoscopy. Anastomotic tissue was processed to study the mechanical tensile strength and histopathology.Results
There was no difference in the rate of conversion to open surgery or in average operating time between the groups. In the sealing device group, there was a significantly higher rate of failure in rectal stump closure (p = 0.042). There was one death in group B due to anastomotic leak. There was no difference in adhesion formation or stenosis. Mid-section anastomosis area was 89.7 mm2 in group A compared with 100 mm2 in group B (p = 0.52). In tensile strength studies, the maximum load resisted by the sample was 13.8 ± 4.9 N (group A) versus 15.7 ± 4.4 N (group B) (p = 0.17). There was no difference between the groups in degree of reepithelialization, number of inflammatory cells, or the presence of microabscesses.Conclusions
Division and sealing of the rectal stump with the LigaSure® device is feasible in the proposed experimental model, but it is less reliable than conventional closure with a stapler, since it has a significantly greater failure rate. Therefore, The LigaSure® device should not be used for this purpose in the clinical setting as this could lead to serious and dramatic complications. 相似文献17.
J.A. Guzmán 《Transplantation proceedings》2012,44(10):2940-2944
BackgroundThis article aims to describe an original technique to correct refluxing native ureters observed during a prerenal transplantation study. The correction is performed by intravesical ligation of the native refluxing ureters at the same time as renal transplantation without simultaneous nephrectomy.MethodsBetween January 2004 and December 2010 we performed intravesical ligation of a refluxing ureter simultaneous with a transplantation procedure without a concomittant native nephrectomy in 12 of 345 subjects (3.47%). The 8 bilateral and 4 unilateral ligations were performed on 11 cadaveric and 1 living-related nonidentical donor transplantations. The implantation of the kidney donor ureter was performed anatomically in the bladder trigone through a transvesical ureteroneocystostomy with a transmural, submucosal antireflux tunnel.ResultsEarly and late postoperative recovery was satisfactory in all patients. There was no documented kidney area pain, proven urinary tract infection, morbidity or mortality attributed to the procedure.ConclusionsIntravesical ligation is a practical technique to manage vesicoureteral reflux into the native ureters simultaneously with the ureteral implantation of the kidney donor in a single surgical renal transplant procedure without native kidney nephrectomy. 相似文献
18.
This paper describes a simplified technique for the repair of incisional hernias. The previous scar is resected, and the peritoneal sac is carefully dissected until it is completely exposed. The sac is opened to liberate structures adherent to the sac or to the area immediately surrounding the defect. The peritoneum is closed and invaginated to form a sac bed underlying the entire extent of the defect, and the mesh is laid on this sac bed. The mesh is then fixed with "U" stitches, reinforcing these by inserting a second line from the edge of the defect to the mesh. Suture material used is polypropylene 1/0 or 2/0. This procedure has been carried out on 15 patients, and after 1 year of follow-up, there has been no recurrence of the hernia. Operating time was reduced, and the surgical technique was found to be easier. Placing a mesh prosthesis inside the hernia sac and fixing it to the abdominal wall with two lines of suturing simplifies the repair procedure, reduces operating time, and is effective in the repair of all incisional hernias. A study is required to compare this outcome with the different mesh repair techniques. 相似文献
19.
Hans Peter Dietz Alejandro Pattillo Garnham Rodrigo Guzmán Rojas 《International urogynecology journal》2016,27(6):909-913
Introduction and hypothesis
Levator avulsion is a risk factor for female pelvic organ prolapse (POP) and recurrence after POP surgery. Imaging diagnosis requires the observation of an abnormal muscle insertion on tomographic ultrasound imaging (TUI). This study was designed to compare the diagnostic performance of the qualitative diagnosis (visual qualitative assessment) to measurement of the distance between muscle insertion and urethra [levator–urethra gap; (LUG)].Methods
This was a retrospective analysis of data obtained in a tertiary urogynecological unit. All patients presented with symptoms of pelvic floor dysfunction and underwent 4D translabial pelvic floor ultrasound (US), supine, and after voiding. Avulsion was defined qualitatively as abnormal muscle insertion and quantitatively as LUG ≥25 mm on at least three consecutive central axial plane slices, with one examiner using both methods. We examined the correlation between both methods and validated them against clinical prolapse, significant organ descent on US, and hiatal ballooning.Results
Between January and July 2013, 233 patients were seen, of whom 202 had complete volume data sets. The qualitative method diagnosed avulsion in 22 % and the quantitative method in 24.3 %. Agreement was good, with a kappa of 0.79 (0.70–0.87). Avulsion diagnosed by either method was associated with clinical and sonographic prolapse and hiatal ballooning, with odds ratios nonsignificantly higher for the quantitative method.Conclusion
Qualitative analysis of slices on TUI and a method using LUG measurement show good agreement for the diagnosis of avulsion. The LUG method is at least equally as valid in its capacity to predict significant prolapse on clinical examination and US, as well as ballooning of the levator hiatus.20.
Jessica Guzmán-Morales Hani El-Gabalawy Minh H. Pham Nicolas Tran-Khanh Marc D. McKee William Wu Michael Centola Caroline D. Hoemann 《BONE》2009,44(4):617-626
Chitosan is a polysaccharide scaffold used to enhance cartilage repair during treatments involving bone marrow stimulation, and it is reported to increase angiogenesis and osteogenesis in vivo. Here, we tested the hypotheses that addition of chitosan particles to the media of human bone marrow stromal cell (BMSC) cultures stimulates osteogenesis by promoting osteoblastic differentiation and by favoring the release of angiogenic factors in vitro. Confluent BMSCs were cultured for 3 weeks with 16% fetal bovine serum, ascorbate-2-phosphate and disodium β-glycerol phosphate, in the absence or presence of dexamethasone, an anti-inflammatory glucocorticoid commonly used as an inducer of BMSC osteoblast differentiation in vitro. As expected, dexamethasone slowed cell division, stimulated alkaline phosphatase activity and enhanced matrix mineralization. Added chitosan particles accumulated intra- and extracellularly and, while not affecting most osteogenic features, they inhibited osteocalcin release to the media at day 14 and interfered with mineralized matrix deposition. Interestingly, dexamethasone promoted cell attachment and suppressed the release and activation of matrix metalloprotease-2 (MMP-2). While chitosan particles had no effect on the release of angiogenic factors, dexamethasone significantly inhibited (p < 0.05 to p < 0.0001) the release of vascular endothelial growth factor (VEGF), granulocyte-macrophage colony stimulating factor (GM-CSF), tumor necrosis factor-alpha (TNF-α), interleukins 1β, 4, 6, and 10 (IL-1β, IL-4, IL-6, IL-10), and a host of other inflammatory factors that were constitutively secreted by BMSCs. These results demonstrate that chitosan particles alone are not sufficient to promote osteoblast differentiation of BMSCs in vitro, and suggest that chitosan promotes osteogenesis in vivo through indirect mechanisms. Our data further show that continuous addition of dexamethasone promotes osteoblastic differentiation in vitro partly by inhibiting gelatinase activity and by suppressing inflammatory cytokines which result in increased cell attachment and cell cycle exit. 相似文献