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61.
In male Wistar rats, shuttle-box avoidance test (5 daily sessions of 50 min) significantly decreased (P less than 0.001) by 30% ascorbic acid (AsAc) level in hypothalamus (HYP), while it left it unmodified in striatum (ST) and in the remaining brain (RB), as opposed to untested rats; AsAc level in HYP showed a significant (P less than 0.001) trend to recovery 24 hours after the end of the test. No correlation was found between the rate of conditioned avoidance responses (CAR) and AsAc levels in the above brain regions. d-Amphetamine (d-A), given s.c. at the dose of 1.0 mg/kg/day for 5 consecutive days, significantly increased AsAc levels by 26% in HYP (P less than 0.005), by 14% in ST (P less than 0.05), and by 33% in RB (P less than 0.001), as opposed to untreated rats; return of AsAc toward baseline levels was negligible 24 hours after d-A withdrawal. The above d-A treatment schedule significantly increased (P 0.05) the rate of CAR in the shuttle-box test. AsAc levels resulted also significantly higher (P less than 0.001) in HYP (+81%) and in RB (+46%) at the end of the test; the AsAc level increase was negligible in ST. Twenty-four hours later, AsAc levels were still significantly higher in RB, but returned toward baseline level in HYP. Again, no correlation was found between CAR rate and regional brain AsAc levels. These results demonstrate that d-A is able to increase regional brain AsAc levels both in control and in tested rats. Since it is well known that systemic administration of AsAc antagonizes some d-A behavioral effects, it is suggested, as a working hypothesis, that the d-A CNS stimulating effect may cause a recruitment of endogenous AsAc, whose task could be a negative neuromodulatory action on the overall effect of d-A on neuronal activity.  相似文献   
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Madelung disease is a rare disorder characterized by the presence of multiple, symmetric, nonencapsulated fatty accumulations diffusely involving the cheeks, the neck, the upper trunk, the shoulder girdle area, and the upper extremities. The cause of this syndrome is unknown, but it has been associated with alcoholism in 60% to 90% of patients. The long-term lipomatous deposits are often large and cosmetically deforming, and the upper aerodigestive tract and great veins may be compressed. We report the case of a man with MD, involving the cervical and upper dorsal regions, who underwent surgical treatment at our Department.  相似文献   
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Despite major improvements concerning its diagnosis and treatment, pancreatic ductal adenocarcinoma (PDAC) remains an aggressive disease with an extremely poor prognosis. Pathology, as interface discipline between basic and clinical medicine, has substantially contributed to the recent developments and has laid the basis for further progress. The definition and classification of precursor lesions of PDAC and their molecular characterization is a fundamental step for the potential identification of biomarkers and the development of imaging methods for early detection. In addition, by integrating findings in humans with the knowledge acquired through the investigation of transgenic mouse models for PDAC, a new model for pancreatic carcinogenesis has been proposed and partially validated in individuals with genetic predisposition for PDAC. The introduction and validation of a standardized system for pathology reporting based on the axial slicing technique has shown that most pancreatic cancer resections are R1 resections and that this is due to inherent anatomical and biological properties of PDAC. This standardized assessment of prognostic relevant parameters represents the basis for the successful conduction of multicentric studies and for the interpretation of their results. Finally, recent studies have shown that distinct molecular subtypes of PDAC exist and are associated with different prognosis and therapy response. The prospective validation of these results and the integration of molecular analyses in a comprehensive pathology report in the context of individualised cancer therapy represent a major challenge for the future.  相似文献   
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Transverse myelitis is a rare autoimmune inflammatory disease often secondary to viral infection of the spinal cord; it frequently has vesico-sphynteric complications. Between January 2000 and December 2005 we performed urodynamic examination on 13 consecutive patients (7 females and 6 males) with previous diagnosis of transverse myelitis. Mean age was 54.5 years; transverse myelitis had been diagnosed a mean of 6.3 years earlier; etiology of myelitis was viral infection in 5 cases, autoimmune in 3 cases, insect bite in 1 case, unknown in 4 cases. The neurological sequelae included paraparesis in 3 cases and tetraparesis in 2 cases. Symptoms: dysuria 46%, slow stream 15%, pollakiuria 23%, urgency 30%; urge incontinence 38%, stress incontinence 15%. 3 patients performed 4 clean intermittent catheterisms (CIC), 2 patients 2 CICs. Eight patients had maximum cystometric capacity above 350 mL, the others had a mean capacity of 223 mL. Four patients showed no bladder sensitivity. Voluntary micturitional reflex was observed in 4 patients. Detrusor overactivity was diagnosed in 9 patients, 10 patients had mean residual post-micturition (RPM) of 218 mL, 2 patients showed detrusor-sphincter dyssynergia, 2 patients were found to be obstructed at pressure-flow study. Urodynamic follow-up is indicated in these patients with or without neurological complications (possibility of detrusor overactivity, urinary retention, detrusor-sphincter dyssynergia); the follow-up personalizes the diagnosis and therapy, and prevents complications.  相似文献   
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