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991.
Patients with imagery neglect (RI+) show peculiar difficulties in orienting themselves in the environment. Navigational impairments could be due to a deficit in creating or using a mental representation of the environment (Guariglia, Piccardi, Iaria, Nico, & Pizzamiglio, 2005) or, according to the BBB model (Burgess, Becker, King, & O'Keefe, 2001), to a specific deficit in a mechanism that transforms an allocentric representation into an egocentric one and vice versa. Previous studies, however, do not allow discerning between a deficit in forming or in using a cognitive map, taking no notice of the fact that these are two different abilities underlain by different neuroanatomical areas, which could be independently impaired. Furthermore, the BBB model has never been verified in a population of brain-damaged patients. Therefore, we administered two tasks that separately assess the ability to create and use a cognitive map of the environment to 28 right brain-damaged patients (4 patients with imagery neglect and 4 patients with perceptual neglect) and 11 healthy participants. RI+ patients showed no specific deficit in creating or using a cognitive map, but failed to transform an egocentric representation of the environment into an allocentric one and vice versa, as predicted by the BBB model.  相似文献   
992.
Management of bilaterally impacted mandibular second and third molars.   总被引:2,自引:0,他引:2  
BACKGROUND: The authors present an interdisciplinary approach to treating bilateral impaction of mandibular second molars. CASE DESCRIPTION: A 22-year-old man had a bilateral deep horizontal impaction of his mandibular second molars. The mandibular third molars lay above and parallel to the second molars. After an orthodontic assessment, the authors decided to distally upright the third molars, remove them and then orthodontically reposition the second molars if they were not ankylosed. This combined orthodontic-surgical approach was successful. CLINICAL IMPLICATIONS: This case illustrates the importance of strong cooperation among various specialists to establish the optimal comprehensive treatment plan.  相似文献   
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994.
In pancreas transplantation, complications can arise at each step of the process, from the initial selection of donors and recipients through the surgical technique itself and the post-operative period, when lifelong immunosuppression is required. In the early steps, careful retrieval and preservation of the pancreas are crucial for the viability of the organ and ultimate success of the transplant. The pancreas is a low-flow gland, making it highly sensitive to transplantation conditions and presenting risk of pancreatitis due to periods of ischemia. The two groups of donors - after brain death (DBD) or after cardiac arrest (DCD) - require different strategies of retrieval and preservation to avoid or reduce the risk of complications developing during and after the transplantation. For DBD donor transplantation, multiorgan retrieval and cold preservation is the conventional technique. Asystole donor (DCD) transplantation, in contrast, can benefit from the newest technologies, such as hypothermic and especially normothermic preservation machines (referred to as NECMO), to optimize organ preservation. The latter has led to an increase in the pool of donors by facilitating recuperation of organs for transplantation that would have been discarded otherwise.  相似文献   
995.
Graefe's Archive for Clinical and Experimental Ophthalmology - The purpose of this study was to evaluate the frequency and clinical presentation of conjunctivitis in hospitalized patients with...  相似文献   
996.
997.
BackgroundTo evaluate the association between COVID-19 vaccination and retinal vein occlusion (RVO).MethodsThis multicentre self-controlled case series included patients with RVO seen in five tertiary referral centres in Italy. All adults who received at least one dose of the BNT162b2, ChAdOx1 nCoV-19, mRNA-1273 or Ad26.COV2.S vaccine and had a first diagnosis of RVO between January 01, 2021, and December 31, 2021 were included. Incidence rate ratios (IRRs) of RVO were estimated using Poisson regression, comparing rates of events in a 28-day period following each dose of vaccination and in the unexposed control periods.Results210 patients were included in the study. No increased risk of RVO was observed after the first dose (1–14 days IRR: 0.87, 95% CI: 0.41–1.85; 15–28 days IRR: 1.01, 95% CI: 0.50–2.04; 1–28 days IRR: 0.94, 95% CI: 0.55–1.58) and second dose of vaccination (1–14 days IRR: 1.21, 95% CI: 0.62–2.37; 15–28 days IRR: 1.08, 95% CI: 0.53–2.20; 1–28 days IRR: 1.16, 95% CI: 0.70–1.90). No association between RVO and vaccination was found in subgroup analyses by type of vaccine, gender and age.ConclusionsThis self-controlled case series found no evidence of an association between RVO and COVID-19 vaccination.Subject terms: Retinal diseases, Epidemiology  相似文献   
998.
999.

Background

The role of supplemental oxygen therapy in the healing of esophagojejunal anastomosis is still very much in an experimental stage. The aim of the present prospective, randomized study was to assess the effect of administration of perioperative supplemental oxygen therapy on esophagojejunal anastomosis, where the risk of leakage is high.

Methods

We enrolled 171 patients between January 2009 and April 2012 who underwent elective open esophagojejunal anastomosis for gastric cancer. Patients were assigned randomly to an oxygen/air mixture with a fraction of inspired oxygen (FiO2) of 30 % (n = 85) or 80 % (n = 86). Administration commenced after induction of anesthesia and was maintained for 6 h after surgery.

Results

The overall anastomotic leak rate was 14.6 % (25 of 171): 17 patients (20 %) had an anastomotic dehiscence in the 30 % FiO2 group and 8 (9.3 %) in the 80 % FiO2 group (P < 0.05). The risk of anastomotic leak was 49 % lower in the 80 % FiO2 group (relative risk 0.61; 95 % confidence interval 0.40–0.95) versus 30 % FiO2.

Conclusions

Supplemental 80 % FiO2 provided during and for 6 h after major gastric cancer surgery to reduce postoperative anastomotic dehiscence should be considered part of ongoing quality improvement activities related to surgical care, with few risks to the patient and little associated cost.  相似文献   
1000.
OBJECTIVE: To investigate the efficacy of imipenem, piperacillin combined with cecropin B in the prevention of lethality in 2 rat models of septic shock. Main outcome measures were bacterial growth in blood and intra-abdominal fluid, endotoxin and TNF-alpha concentrations in plasma, and lethality. BACKGROUND: Sepsis remains a serious clinical problem despite intense efforts to improve survival. It is a major cause of morbidity and mortality in hospitalized patients. The primary cause of Gram-negative shock results from activation of host effector cells by endotoxin, the lipopolysaccharide (LPS) associated with cell membranes of Gram-negative bacteria. METHODS: Adult male Wistar rats were given (1). an intraperitoneal injection of 1 mg of Escherichia coli 0111:B4 LPS or (2). 2 x 1010 CFU of E. coli ATCC 25922. All animals were randomized to receive intraperitoneally isotonic sodium chloride solution, 1 mg/kg cecropin B, 20 mg/kg imipenem, and 120 mg/kg piperacillin alone and combined with 1 mg/kg cecropin B. Each group included 20 animals.RESULTS All compounds reduced the lethality when compared with controls. Piperacillin and imipenem significantly reduced the lethality and the number of E. coli in abdominal fluid compared with saline treatment. On the other hand, each betalactam determined an increase of plasma endotoxin and TNF-alpha concentration. Combination between cecropin B and betalactams showed to be the most effective treatment in reducing all variables measured. CONCLUSION: Cecropin B enhances betalactams activities in Gram-negative sepic shock rat models.  相似文献   
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