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951.
Solid pseudopapillary neoplasm of the pancreas is a low-grade malignant tumor that predominantly affects young women in their third and fourth decade. Etiology and risk factors are unknown. Clinical symptoms are aspecific and most commonly due to mass effect. Diagnosis is made by computed tomography scan or magnetic resonance imaging and histological characterization is obtained by endoscopic ultrasound-guided fine needle biopsy. Microscopically, these lesions are composed by both solid and pseudopapillary structures with necrotic and hemorrhagic areas. Occasionally, the biological behavior is aggressive with tumor recurrence and distant metastasis. Usually, curative R0 surgical resection is the best option able to provide long term survival even in advanced disease. Unresectable disease is the main predictor of poor prognosis. Chemotherapy and radiotherapy regimens are not well standardized. However, they could be effective in reducing tumor size as neoadjuvant treatment or disease control in palliative setting. Although complete surgical resection provides a cure rate of > 95%, considering young age of the patients and morbidity associated to pancreatic surgery, further studies are needed to better investigate risk factors and responsiveness to hormones in order to allow early diagnosis and follow up strategies that could avoid unnecessary surgery in less aggressive disease. 相似文献
952.
Glaucoma,a progressive age-related optic neuropathy characterized by the death of retinal ganglion cells,is the most common neurodegenerative cause of irreversible blindness worldwide.The therapeutic management of glaucoma,which is limited to lowering intraocular pressure,is still a challenge since visual loss progresses in a significant percentage of treated patients.Restricted dietary regimens have received considerable attention as adjuvant strategy for attenuating or delaying the progression of neurodegenerative diseases.Here we discuss the literature exploring the effects of modified eating patterns on retinal aging and resistance to stressor stimuli. 相似文献
953.
Ophelia Veraitch Raffaele Gianotti Gerardo Ferrara Carlo F. Tomasini Manuraj Singh Iris Zalaudek Catherine M. Stefanato 《Journal of cutaneous pathology》2017,44(3):256-278
The stratum corneum or horny layer is the uppermost layer of the epidermis, and is mainly responsible for the skin's barrier function. In spite of its complexity at the ultrastructural and molecular level, the features accessible to visualization on conventional histology are relatively limited. Nevertheless, knowledge of subtle clues that one may observe in the stratum corneum can prove useful in a wide range of situations in dermatopathology. We herein review a selection of common and rare entities in which the horny layer may reveal significantly important hints for the diagnosis. These clues include parakeratosis and its different patterns (focal, confluent, alternating, associated with spongiosis, epidermal hyperplasia or lichenoid changes), subcorneal acantholysis, infectious organisms in the stratum corneum (including fungal, bacterial and parasitic), thickening or thinning of the stratum corneum and the presence of different kinds of pigment. Even when normal, the horny layer may prove to be useful when seen in association with severe epidermal damage, a combination of features testifying to the acute nature of the underlying pathological process. 相似文献
954.
955.
956.
Van de Velde M Van Schoubroeck D Lewi LE Marcus MA Jani JC Missant C Teunkens A Deprest JA 《Anesthesia and analgesia》2005,101(1):251-8, table of contents
Obstetric endoscopy procedures are routinely performed at our institution to treat selected complications of monochorionic twin gestation. We perform these procedures under combined spinal epidural anesthesia plus maternal sedation. In the absence of general anesthesia, fetal immobilization is not achieved. We hypothesized that remifentanil would induce adequate maternal sedation and provide fetal immobilization, which is equal or superior to that induced by diazepam. Fifty-four second trimester pregnant women were included in this randomized, double-blind trial. After combined spinal epidural anesthesia, maternal sedation was initiated using either incremental doses of diazepam or a continuous infusion of remifentanil. Maternal sedation, hemodynamics, side effects, and fetal hemodynamics and immobilization were evaluated before, during, and for 60 min after surgery. Remifentanil produced adequate maternal sedation with mild but clinically irrelevant respiratory depression (respiratory rate 13 +/- 4 breaths/min and Pco(2) 38.6 +/- 4 mm Hg at 40 min of surgery), whereas diazepam resulted in a more pronounced maternal sedation but no respiratory depression (respiratory rate 18 +/- 3 breaths/min and Pco(2) 32.7 +/- 3 mm Hg at 40 min of surgery). Compared with diazepam, fetal immobilization with remifentanil occurred faster and was more pronounced, resulting in improved surgical conditions; the number of gross body and limb movements was 12 +/- 4 (diazepam) versus 2 +/- 1 (remifentanil) at 40 min of surgery. Because of this, the mean (range) duration of surgery was significantly shorter in the remifentanil-treated patients, 60 (54-71) min versus 80 (60-90) min in the diazepam group. We conclude that remifentanil produces improved fetal immobilization with good maternal sedation and only minimal effects on maternal respiration. 相似文献
957.
Roberto Santambrogio MD Enrico Opocher MD Massimo Zuin MD Carlo Selmi MD PhD Emanuela Bertolini MD Mara Costa MD Matteo Conti MD Marco Montorsi MD 《Annals of surgical oncology》2009,16(12):3289-3298
Background
This study compared two homogeneous groups of patients submitted to either surgical resection (HR) or laparoscopic radiofrequency ablation (LRFA) for the treatment of hepatocellular carcinoma (HCC). When compatible with the liver functional reserve, HR remains the treatment of choice for HCC, while LRFA seems to be a promising, less invasive alternative. We thus compared HR or LRFA for short- and long-term outcomes in patients with a single HCC nodule and Child-Pugh class A liver cirrhosis. 相似文献958.
Luca Aldrighetti Carlo Pulitanò Marco Catena Marcella Arru Eleonora Guzzetti Massimiliano Casati Laura Comotti Gianfranco Ferla 《Journal of gastrointestinal surgery》2008,12(3):457-462
Background Left lateral sectionectomy is one of the most commonly performed laparoscopic liver resections, but limited clinical data
are actually available to support the advantage of laparoscopic versus open-liver surgery. The present study compared the
short-term outcomes of laparoscopic versus open surgery in a case-matched analysis.
Materials and Methods Surgical outcome of 20 patients who underwent left lateral sectionectomy by laparoscopic approach (LHR group) from September
2005 to January 2007 were compared in a case-control analysis with those of 20 patients who underwent open left lateral sectionectomy
(OHR group). Both groups were similar for: tumor size, preoperative laboratory data, presence of cirrhosis, and histology
of the lesion. Surgical procedures were performed in both groups combining the ultrasonic dissector and the ultrasonic coagulating
cutter without portal clamping.
Results Compared with OHR, the LHR group had a decreased blood loss (165 mL versus 214 mL, P = 0.001), and earlier postoperative recovery (4.5 versus 5.8 days, P = 0.003). There were no significant differences in terms of surgical margin and operative time. Morbidity was comparable
between the two groups, but two cases of postoperative ascites were recorded in two cirrhotic patients in the OHR. Major complications
were not observed in either groups.
Conclusions Laparoscopic resection results in reduced operative blood loss and earlier recovery with oncologic clearance and operative
time comparable with open surgery. Laparoscopic liver surgery may be considered the approach of choice for tumors located
in the left hepatic lobe. 相似文献
959.
Occlusion of the pancreatic duct versus pancreaticojejunostomy: a prospective randomized trial 总被引:14,自引:0,他引:14
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Tran K Van Eijck C Di Carlo V Hop WC Zerbi A Balzano G Jeekel H 《Annals of surgery》2002,236(4):422-428
OBJECTIVE: Using a prospective randomized study to assess postoperative morbidity and pancreatic function after pancreaticoduodenectomy with pancreaticojejunostomy and duct occlusion without pancreaticojejunostomy. SUMMARY BACKGROUND DATA: Postoperative complications after pancreaticoduodenectomy are largely due to leakage of the pancreaticoenterostomy. Pancreatic duct occlusion without anastomosis of the pancreatic remnant may prevent these complications. METHODS: A prospective randomized study was performed in a nonselected series of 169 patients with suspected pancreatic and periampullary cancer. In 86 patients the pancreatic duct was occluded without anastomosis to pancreatic remnant, and in 83 patients a pancreaticojejunostomy was performed after pancreaticoduodenectomy. Postoperative complications were the endpoint of the study. All relevant data concerning patient demographics and postoperative morbidity and mortality as well as endocrine and exocrine function were analyzed. At 3 and 12 months after surgery, evaluation of weight loss, stools, and the use of antidiabetics and pancreatic enzyme was repeated. RESULTS: Patient characteristics were comparable in both groups. There were no differences in median blood loss, duration of operation, and hospital stay. No significant difference was noted in postoperative complications, mortality, and exocrine insufficiency. The incidence of diabetes mellitus was significantly higher in patients with duct occlusion. CONCLUSIONS: Duct occlusion without pancreaticojejunostomy does not reduce postoperative complications but significantly increases the risk of endocrine pancreatic insufficiency after duct occlusion. 相似文献
960.
Virtual Gastroduodenoscopy: A New Look at the Bypassed Stomach and Duodenum After Laparoscopic Roux-en-Y Gastric Bypass for Morbid Obesity 总被引:2,自引:4,他引:2
Silecchia G Catalano C Gentileschi P Elmore U Restuccia A Gagner M Basso N 《Obesity surgery》2002,12(1):39-48
Background: After open or laparoscopic Roux-en-Y gastric bypass (RYGBP) for morbid obesity, the bypassed stomach and duodenum
are not readily available for radiological and endoscopic evaluation. Furthermore, little is known about the long-term physiologic
and histologic changes that occur in the bypassed GI segments following these procedures. Many alternative radiological and
endoscopic techniques have been described to access the distal gastric pouch and the duodenum after RYGBP. Apart from percutaneous
gastrografin? studies, all these techniques require the insertion of a gastrostomy tube in the distal stomach. Methods: a
new diagnostic method to access the bypassed segments by virtual CT gastroscopy (VG) was used in 5 morbidly obese patients
who underwent laparoscopic RYGBP (LRYGBP). Results: All patients tolerated the procedure well, which appears safe and suitable
for an outpatient setting.The virtual images offered an excellent intraluminal view of the stomach and duodenum. Conclusions:
VG holds promise as the method of choice in the follow-up of LRYGB patients, having the potential to detect inflammatory changes
and cancer in the excluded segments early. 相似文献