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81.
To investigate the effect of the terminal complement complex (TCC) on the central nervous system, we injected both the cytolytically active and the inactive complexes into the lateral ventricle of rats. Both complexes promoted accumulation of leukocytes into the cerebrospinal fluid at 4-6 h post-injection. The cells recovered at this time were mostly polymorphonuclear leukocytes (PMN) that were partially replaced by mononuclear cells at 12 h. A direct contribution of the complexes to the in-vivo migration of leukocytes was ruled out by their inability to be chemotactic for rat PMN. Contaminating C5a is unlikely to be responsible for the effect of TCC because it failed to mobilize leukocytes when injected into the lateral ventricle. Histological analysis of rat brains 6 hours after injection of TCC revealed marked leukocyte infiltration of the choroid plexus, increased expression of intercellular adhesion molecule-1 and egression of leukocytes out of the meningeal vessels. The cerebrospinal fluid of rats treated with TCC exhibited chemotactic activity for rat PMN and increased levels of growth related oncogene/cytokine-induced neutrophil chemoattractant-1 and monocyte chemoattractant protein-1 preceding the accumulation of leukocytes. Elevated concentration of IL-1 beta was also found in the cerebrospinal fluid and in periventricular areas of rats treated with TCC.  相似文献   
82.
Previous research has clearly documented that risky decisionmaking is different in young and older adults. Yet, there hasbeen a relative dearth of research that seeks to understandsuch age-related changes in the neural activities associatedwith risk taking. To address this research issue, 21 men (12young men, mean age 29.9 ± 6.2 years and 9 older men,mean age 65.2 ± 4.2 years) performed a risky-gains taskwhile their brain activities were monitored by an fMRI scanner.The older adults, relative to their younger peers, presentedwith contralateral prefrontal activity, particularly at theorbitofrontal cortex. Furthermore, stronger activation of theright insula was observed for the older-aged participants comparedto the younger-aged adults. The findings of this study are consistentwith the a priori speculations established in accordance withthe HAROLD model as well as previous findings. Findings of thisstudy suggest that when making risky decisions, there may bepossible neuropsychological mechanisms underlying the changein impulsive and risk-taking behaviors during the course ofnatural ageing.  相似文献   
83.
MRI of the prostate can aid in many aspects of prostate cancer management, from initial detection to treatment planning and follow-up. This review describes the current strengths and limitations of conventional anatomic and molecular MR imaging techniques (including MR spectroscopic imaging and dynamic contrast-enhanced imaging) for aiding prostate cancer management. It also describes promising emerging approaches for acquiring, analyzing, and applying MR imaging data, and the major research and educational efforts that will be required to realize the potential of prostate MR imaging in routine clinical practice.  相似文献   
84.
Solid splenic masses: evaluation with 18F-FDG PET/CT.   总被引:4,自引:0,他引:4  
Our objective was to assess the role of (18)F-FDG PET/CT in the evaluation of solid splenic masses in patients with a known malignancy and in incidentally found lesions in patients without known malignancy. METHODS: Two groups of patients were assessed: (a) 68 patients with known malignancy and a focal lesion on PET or a solid mass on CT portions of the PET/CT study; and (b) 20 patients with solid splenic masses on conventional imaging without known malignancy. The standard of reference was histology (n = 16) or imaging and clinical follow-up (n = 72). The lesion size, the presence of a single versus multiple splenic lesions, and the intensity of (18)F-FDG uptake expressed as a standardized uptake value (SUV) were recorded. The ratio of the SUV in the splenic lesion to the background normal splenic uptake was also calculated. These parameters were compared between benign and malignant lesions within each of the 2 groups of patients and between the 2 groups. RESULTS: The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of (18)F-FDG PET/CT in differentiating benign from malignant solid splenic lesions in patients with and without malignant disease were 100%, 100%, 100%, and 100% versus 100%, 83%, 80%, and 100%, respectively. In patients with known malignant disease, an SUV threshold of 2.3 correctly differentiated benign from malignant lesions with the sensitivity, specificity, PPV, and NPV of 100%, 100%, 100%, and 100%, respectively. In patients without known malignant disease, false-positive results were due to granulomatous diseases (n = 2). CONCLUSION: (18)F-FDG PET can reliably discriminate between benign and malignant solid splenic masses in patients with known (18)F-FDG-avid malignancy. It also appears to have a high NPV in patients with solid splenic masses, without known malignant disease. (18)F-FDG-avid splenic masses in patients without a known malignancy should be further evaluated as, in our series, 80% of them were malignant.  相似文献   
85.
Nasal amputation and nasomaxillary defects, need to reconstruct the internal lining, osteochondral structure, and external coating of the nose. Authors report a 70-year-old male and a 65-year-old female treated for nasomaxillary defects (Brown JS, Shaw RJ. The Lancet Oncology 2010;11:1001–1008) due to squamous cell carcinoma (SCC) where the tip of the nose was preserved. A new custom design of the radial forearm free flap (RFFF) consisting on a subcutaneous tissue (SCT) component, a skin paddle for the internal nasal vault lining, and a skin paddle for the external nasal skin coating was raised to treat both total thickness nasal defects. The dimension of each skin paddle corresponds to the defect measurements. The skin incisions of the custom design correspond to those of a conventional RFFF. The SCT component was harvested in a subcutaneous plane continuously with the skin island for the internal nasal lining which is drawn on the ulnar skin of the forearm. The component for the external nasal coating was drawn on the radial skin area of the flap. No postoperative complications and a satisfactory outcome was reported after 1 year of follow-up. This new custom design of the RFFF is described for reconstruction of nasomaxillary defects when the tip of the nose is preserved.  相似文献   
86.
Intraepithelial carcinoma of the anus in homosexual men   总被引:8,自引:8,他引:8  
Anal warts (condylomata acuminata) from seven homosexual men revealed intraepithelial carcinoma (carcinomain situ) within the condylomatous tissue or in adjacent anal mucosa. All lesions displayed morphologic evidence of papillomavirus infection and two of the seven revealed histologic changes characteristic of herpes simplex infection. This association of viral infection with malignant transformation indicates that persistent or recurrent anal warts should be excised and thoroughly examined by histologic techniques. Since four of the seven patients had histories suspicious for or diagnostic of the acquired immunodeficiency syndrome (AIDS), we further suggest that homosexual men with persistent or recurrent perianal lesons be evaluated for the presence of the syndrome.  相似文献   
87.
We have assessed the prognostic significance of ST segment depression in the anterior precordial leads in patients with an acute inferior infarction. Eighty-four patients with ST segment depression greater than or equal to 1 mm in at least 2 chest leads (Group A) and 82 patients without ST depression (Group B), all admitted to the hospital within 24 hours from the onset of an acute inferior myocardial infarction, were evaluated. Patients with an old infarction, those with intraventricular conduction abnormalities or other causes that could modify the ST segment were excluded from the study. The number of patients affected by complications during the hospital stay was significantly higher in group A (54 patients of group A vs 27 of group B, p less than 0,001). Death, left ventricular failure, ventricular arrhythmias were considerably higher in group A. Moreover we observed that the persistence of the ST segment depression for more than 24 hours identified a subgroup of patients with a very strong risk of complications, particularly death and left ventricular failure. The follow up after 3-6 months, however, did not show any significant difference in both groups. In conclusion, from our study it appears that patients with an inferior infarction precordial ST segment depression have a graver prognosis in the acute phase while their mid-term fate does not seem to be influenced by the presence of this electrocardiographic abnormality.  相似文献   
88.
In several murine models of transplantation, the “cross-dressing” of recipient antigen presenting cells (APCs) with intact donor major histocompatibility complex (MHC) derived from allograft-released small extracellular vesicles (sEVs) has been recently described as a key mechanism in eliciting and sustaining alloimmune responses. Investigation of these processes in clinical organ transplantation has, however, been hampered by the lack of sensitivity of conventional instruments and assays. We have employed advanced imaging flow cytometry (iFCM) to explore the kinetics of allograft sEV release and the extent to which donor sEVs might induce cross-dressing following liver and kidney transplantation. We report for the first time that recipient APC cross-dressing can be transiently detected in the circulation shortly after liver, but not kidney, transplantation in association with the release of HLA-bearing allograft-derived sEVs. In liver transplant recipients the majority of circulating cells exhibiting donor HLA are indeed cross-dressed cells and not passenger leukocytes. In keeping with experimental animal data, the downstream functional consequences of the transfer of circulating sEVs harvested from human transplant recipients varies depending on the type of transplant and time posttransplant. sEVs released shortly after liver, but not kidney, transplantation exhibit immunoinhibitory effects that could influence liver allograft immunogenicity.  相似文献   
89.
Purpose

Fatty acids (FA), particularly polyunsaturated (PUFA) ones, are involved in the regulation of glycemic control, lipid metabolism, and inflammation. The aim of the study was to assess patient FA profile in relation to obesity, lipid and carbohydrate metabolism disturbances, and weight loss.

Materials and Methods

The studied group consisted of 51 patients with extreme obesity, 23 of whom achieved radical weight reduction within 1 year after a laparoscopic sleeve gastrectomy (LSG). FA levels were determined using gas chromatography with flame ionization detection.

Results

Patients with extreme obesity and higher serum PUFA content have lower serum levels of SFA and MUFA (especially myristic, palmitic, lignoceric acids and palmitoleic, oleic acids), as well as lower triglyceride and higher HDL-cholesterol concentrations and it was not influenced by CEPT Taq1B variant. At baseline, the fatty acid profile of patients with type II diabetes differ from patients with dyslipidemia. In patients who had lost weight, significantly lower levels of selected saturated FA and major trans-fatty acid, elaidic, were found. Moreover, the proportion of PUFA was increased.

Conclusion

In extreme obesity, higher PUFA exert their favorable effects on serum lipids. Significant weight reduction after the bariatric surgery is associated with beneficial changes in the fatty acid profile.

Graphical Abstract
  相似文献   
90.
PURPOSE: The aim of the present study is to verify whether patients with partial epilepsy receiving levetiracetam (LEV) as an add-on treatment show an improvement in cognitive function. METHODS: A neuropsychological battery of tests was administered to 35 patients with partial epilepsy before the assumption of LEV and after the achievement of the therapeutical dose of this drug, 7 weeks later. A control group of 35 patients with partial epilepsy was administered the same battery of tests twice, at the same time interval as the LEV group. The controls were administered the same pharmacological treatment, which did not include LEV in either of the two sessions. RESULTS: We found a statistically significant improvement in cognitive functioning, i.e. in attention and oral fluency, in patients receiving LEV compared to the controls. The responders to LEV were 28.6%. CONCLUSIONS: LEV as an add-on therapy improved attention level and verbal fluency in our sample of patients with partial epilepsy. It is reasonable to assume that LEV may influence the metabolism of attention and of language area, as already suggested for piracetam (PIR) from which LEV derives. Further studies are needed to confirm these findings.  相似文献   
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