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921.
The pancreaticoduodenectomy (PD) procedure may lead to pancreatic exocrine and endocrine insufficiency. There are several types of reconstruction for this kind of operation. Pancreaticogastrostomy (PG) was introduced to reduce the rate of postoperative pancreatic fistula. Although some randomized control trials have shown no differences regarding pancreatic leakage between PG and pancreaticojejunostomy (PJ), recently some reports reveal benefits from the PG over the PJ. Some surgeons concern about the performing of the PG and inactivation of pancreatic enzymes being in contact with the gastric juice, and the detrimental results over the exocrine pancreatic function. The pancreatic exocrine function can be measured with direct and indirect tests. Direct tests have the highest sensitivity and specificity for detection of exocrine insufficiency but require tube placement. Among the tubeless indirect tests, the van de Kamer stool fat analysis remains the standard to diagnose fat malabsorption. The patient compliance and time consuming makes it not so suitable for its clinical use. Fecal immunoreactive elastase test is employed for screening of exocrine insufficiency, is not cumbersome, and has been used to study pancreatic function after resection. We analyze the FE1 levels in our patients after the PD with two types of reconstruction, PG and PJ, and we discuss some considerations about the pancreaticointestinal drainage method after pancreaticoduodenectomy.  相似文献   
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Low-level laser therapy (LLLT) promotes biomodulation of wound healing and literature reports that light delivery during the inflammation could play a different role compared with latter phases of the healing process. The objective of this study was to investigate whether single dose of a red laser (λ?=?660 nm) is different from fractionated delivery protocol in full thickness burns. Two lesions were inflicted on the back of 36 rats. In the fractionated dose group (FG), the lesions were irradiated with 1 J/cm² on days 1, 3, 8, and 10 post-wounding. In the single dose group (SG), the lesions were irradiated with 4 J/cm² on day 1, immediately after injury. Control lesions (CG) received no light and were left to heal spontaneously. Blood flow was measured on days 1, 3, 8, 10, 15, and 21 using laser Doppler flowmetry. Animals were killed on days 3, 8, 10, 15, and 21. Skin specimens were obtained and routinely processed for hematoxylin and eosin. The specimens were evaluated according to differential leukocyte counting and angiogenesis. Statistical analysis was performed, and significance was accepted at p?<?0.05. Irradiated groups showed a peak of new vessels on day 15 while, for CG, the peak was on day 21. On day 21, FG exhibited a significantly greater number of cumulative neutrophils while SG showed a higher number of mononuclear cells. Our results confirm that both protocols used accelerate angiogenesis and stimulate leukocyte chemotaxis on burn treatment. In addition, this work suggests that a single-dose LLLT accelerates the inflammatory phase of skin repair.  相似文献   
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Angiogenesis, the complex process of formation of new blood vessels from pre-existing blood vessels, which involves the participation of several pro- and anti-angiogenic factors, is implicated in many physiological and pathological conditions. Nanoparticle-based anti-angiogenic activity at the tumour tissue, harnessed by the Enhanced Permeability and Retention Effect (EPR effect), could potentially become a breakthrough therapy to halt tumour progression. Herein, we evaluate the anti-angiogenic effect of ZnWO4 nanoparticles (NPs). The nanoparticles were obtained by microwave-assisted hydrothermal synthesis (MAHS) at 120?°C for 60?min and were structurally characterised by X-ray diffraction (XRD) and micro-Raman (MR) spectroscopy. The mean size and polydispersity index were estimated by Zeta potential analysis. The XRD analysis revealed structural organisation at a long-range order, with an average crystallite size of around 3.67?nm, while MR revealed short-range order for ZnWO4. The anti-angiogenic potential of zinc tungstate nanoparticles was investigated through the chorioallantoic membrane assay (CAM) using fertilised chicken eggs. We demonstrate, in an unprecedented way, that nanocrystalline ZnWO4 NPs obtained by MAHS, at low reaction temperatures, showed excellent anti-angiogenic properties even at low concentrations. The ZnWO4 NPs were further evaluated for its cytotoxicity in vitro.  相似文献   
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