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921.
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Gardênia Matos Paraguassú Milena Góes da Guarda Flávia Calo Aquino Xavier Maria Cristina Teixeira Cangussu Tânia Tavares Rodriguez Maria José Pedreira Ramalho Antônio Luis Barbosa Pinheiro Luciana Maria Pedreira Ramalho 《Lasers in medical science》2014,29(2):773-779
The aim of this study was to assess morphometrically and histologically, the effects of light-emitting diode (LED) (λ630?±?20 nm) phototherapy on reepithelialization and wound contraction during tissue repair in hypothyroid rats. Thyroid hormone deficiency has been associated with disorders of tissue repair. LED phototherapy has been studied using several healing models, but their usefulness in the improvement of hypothyroidism wound healing remains unknown. Under general anesthesia, a standard surgical wound (1 cm2) was produced on the dorsum of 48 male Wistar rats divided into four groups of 12 animals each: EC—control euthyroid, ED—euthyroid + LED, HC—control hypothyroid, and HD—Hypothyroid + LED. The irradiation started immediately after surgery and was repeated every other day for 7 and 14 days. Photographs of the wound were taken at the day of the surgical procedure and on days 8 and 15 after surgery, when animals’ deaths occurred. The specimens were removed, routinely processed, and stained with hematoxylin/eosin. Seven days after the surgery, it was possible to observe statistically significant reductions in the wound area of the irradiated euthyroid group, in comparison to hypothyroid group, irradiated and non-irradiated (ANOVA, p?<?0.05). The reepithelialization was significantly higher in the euthyroid and hypothyroid groups irradiated with LED than in the non-irradiated groups (Fisher’s test, p?<?0.05). No significant difference was found in the experimental period of 14 days among the groups. The hypothyroidism delayed wound healing and the LED phototherapy, at these specific parameters, improved the process of reepithelialization in the presence of hypothyroidism. 相似文献
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928.
Luis Felipe Brandao Riccardo AutorinoHomayoun Zargar Jayram KrishnanHumberto Laydner Oktay AkcaMaria Carmen Mir Dinesh SamarasekeraRobert Stein Jihad Kaouk 《European urology》2014
Background
Recent evidence supports the use of robotic surgery for the minimally invasive surgical management of adrenal masses.Objective
To describe a contemporary step-by-step technique of robotic adrenalectomy (RA), to provide tips and tricks to help ensure a safe and effective implementation of the procedure, and to compare its outcomes with those of laparoscopic adrenalectomy (LA).Design, setting, and participants
We retrospectively reviewed the medical charts of consecutive patients who underwent RA performed by a single surgeon between April 2010 and October 2013. LA cases performed by the same surgeon between January 2004 and May 2010 were considered the control group.Surgical procedure
The main steps of our current surgical technique for RA are described in this video tutorial: patient positioning, port placement, and robot docking; exposure of the adrenal gland; identification and control of the adrenal vein; circumferential dissection of the adrenal gland; and specimen retrieval and closure.Outcome measurements and statistical analysis
Demographic parameters and main surgical outcomes were assessed.Results and limitations
A total of 76 cases (RA: 30; LA: 46) were included in the analysis. Median tumor size on computed tomography (CT) was significantly larger in the LA group (3 cm [interquartile range (IQR): 3] vs 4 cm [IQR: 3]; p = 0.002). A significantly lower median estimated blood loss was recorded for the robotic group (50 ml [IQR: 50] vs 100 ml [IQR: 288]; p = 0.02). The RA group presented five minor complications (16.7%) and one major (Clavien 3b) complication (3.3%), whereas four minor complications (8.7%) and one major (Clavien 3b) complication (2.3%) were observed in the LA group. No significant difference was noted between groups in terms of malignant histology (p = 0.66) and positive margin rate (p = 0.60). Distribution of pheochromocytomas in the LA group was significantly higher than in the RA group (43.5% vs 16.7%; p = 0.02).Conclusions
The standardization of each surgical step optimizes the RA procedure. The robotic approach can be applied for a wide range of adrenal indications, recapitulating the safety and effectiveness of open surgery and potentially improving the outcomes of standard laparoscopy.Patient summary
In this report we detail our surgical technique for robotic removal of adrenal masses. This procedure has been standardized and can be offered to patients, with excellent outcomes. 相似文献929.
Malte Rieken Rosa S. Djajadiningrat Luis A. Kluth Ricardo L. Favaretto Evanguelos Xylinas Gustavo C. Guimaraes Fernando A. Soares Matthew Kent Daniel D. Sjoberg Simon Horenblas Shahrokh F. Shariat 《European urology》2014
Disease recurrence occurs frequently after surgical treatment for squamous cell carcinoma of the penis (SCCp). We sought to determine prognostic factors that influence cancer-specific mortality (CSM) after disease recurrence in patients with SCCp. We performed a retrospective analysis of 314 patients who experienced disease recurrence after surgical treatment for SCCp between 1949 and 2012. Competing risk regression analysis addressed factors associated with CSM after SCCp recurrence. Median time from surgery to disease recurrence was 10.5 mo (interquartile range [IQR]: 5.9–21.3). Of the recurrences, 165 (53%), 118 (38%), and 31 (9.9%) were local, regional, or distant, respectively. Within a median follow-up of 4.5 yr (IQR: 2.0–6.5), 108 patients died of SCCp and 41 patients died of causes other than SCCp. Shorter time to disease recurrence was found to be significantly associated with a higher risk of CSM (p = 0.0006). Lymph node metastasis at the time of initial treatment (subdistribution hazard ratio [SHR]: 1.96; 95% confidence interval [CI] 1.23– 3.11; p = 0.005) and regional recurrence (SHR: 4.14; 95% CI, 2.16–7.93; p < 0.0001) or distant recurrence (SHR: 5.75; 95% CI, 2.59–12.73; p < 0.0001) were associated with increased risk of CSM after disease recurrence. Inclusion of time to recurrence into risk stratification may help patient counseling and treatment planning. 相似文献
930.
3D Assessment of Cortical Bone Porosity and Tissue Mineral Density Using High‐Resolution µCT: Effects of Resolution and Threshold Method 下载免费PDF全文
Stephen B Doty Luis Cardoso Susannah P Fritton 《Journal of bone and mineral research》2014,29(1):142-150
Current micro–computed tomography (µCT) systems allow scanning bone at resolutions capable of three‐dimensional (3D) characterization of intracortical vascular porosity and osteocyte lacunae. However, the scanning and reconstruction parameters along with the image segmentation method affect the accuracy of the measurements. In this study, the effects of scanning resolution and image threshold method in quantifying small features of cortical bone (vascular porosity, vascular canal diameter and separation, lacunar porosity and density, and tissue mineral density) were analyzed. Cortical bone from the tibia of Sprague‐Dawley rats was scanned at 1‐µm and 4‐µm resolution, reconstructions were density‐calibrated, and volumes of interest were segmented using approaches based on edge‐detection or histogram analysis. In 1‐µm resolution scans, the osteocyte lacunar spaces could be visualized, and it was possible to separate the lacunar porosity from the vascular porosity. At 4‐µm resolution, the vascular porosity and vascular canal diameter were underestimated, and osteocyte lacunae were not effectively detected, whereas the vascular canal separation and tissue mineral density were overestimated compared to 1‐µm resolution. Resolution had a much greater effect on the measurements than did threshold method, showing partial volume effects at resolutions coarser than 2 µm in two separate analyses, one of which assessed the effect of resolution on an object of known size with similar architecture to a vascular pore. Although there was little difference when using the edge‐detection versus histogram‐based threshold approaches, edge‐detection was somewhat more effective in delineating canal architecture at finer resolutions (1–2 µm). In addition, use of a high‐resolution (1 µm) density‐based threshold on lower resolution (4 µm) density‐calibrated images was not effective in improving the lower‐resolution measurements. In conclusion, if measuring cortical vascular microarchitecture, especially in small animals, a µCT resolution of 1 to 2 µm is appropriate, whereas a resolution of at least 1 µm is necessary when assessing osteocyte lacunar porosity. © 2014 American Society for Bone and Mineral Research. 相似文献