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1.
The aim of this study was to investigate the histological and biological features of the human cerebellar cortex development and differentiation. We analyzed 52 brains of fetal and infant death victims, aged from 17 gestational weeks to 12th postnatal month. In particular, in the cerebellar cortex at different ages we evaluated, besides the structural aspects, the expression of several biomarkers implicated in proliferative processes (c-fos, PCNA and apoptosis). We observed morphological patterns progressively evolving every month, from the indefinite structure of the second gestational trimester to the four-layered structure (external granular layer, molecular layer, Purkinje cell layer, internal granular layer) of the late fetal cortex and subsequently to the three-layered postnatal definitive morphology, due to involution of the external granular layer. The evaluation of the biological features of the cerebellar cortex showed high proliferative activity mainly confined to the transient external granular layer in prenatal life, and high apoptotic index after birth. Thus, the histological examination, better with the support of biomarker investigations, allows with accuracy to describe the dynamic sequence of steps that occur in human cerebellar cortex development and to establish in each case the age, namely the pre- or postnatal month of life. Consequently, we can diagnose delayed or altered processes of differentiation during the development of the human cerebellar cortex.  相似文献   
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Male Sprague-Dawley rats injected (i.p.) at 1500h with L-acetyl-carnitine in doses of 10, 30 or 90 mg/kg exhibited a notable increase in their pineal and serum melatonin content 1 hr later. Likewise, L-acetyl-carnitine administered in the same dose range induced a significant increase of pineal and serum melatonin content in rats treated at 0100h, following exposure of 30 min to bright white light to suppress endogenous melatonin. Under in vitro experimental conditions, however, 60 min of coincubation of isolated rat pineal glands with L-acetyl-carnitine (10(-5) M) did not result in an elevation in melatonin accumulated in the incubation medium. These results demonstrate that, in vivo, L-acetyl-carnitine can exert a modulatory action on synthesis and release of melatonin, possibly by modifying noradrenergic transmission and signal transduction in the pineal gland.  相似文献   
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OBJECTIVE: A higher mortality has been reported after pneumonectomy over the age of 70. The aim of the study was to quantify the additional risk due to age after standard pneumonectomy for lung cancer by a case-control study. METHODS: Our clinical database was reviewed to search for patients aged 70 years or more who underwent standard pneumonectomy for lung cancer between 1998 and 2005. A control group of patients younger than 70 (one case/two controls) was matched for sex, cardiovascular disease, American Association of Anaesthetists score, respiratory function, side of pneumonectomy, induction chemotherapy and stage. Overall mortality and morbidity were compared. Long-term survival data were also analysed. RESULTS: During the considered period, 35 patients aged 70 years or more underwent pneumonectomy (30 males, median age 73 years, 15 right-sided procedures). The control group was composed of 70 patients. The two groups were homogeneous in the variables used for matching. Overall mortality and morbidity were 11.4 and 54.2% in the elderly group as compared to 4.3 and 41.6% in controls (p-value not significant). Elderly patients experienced a higher rate of respiratory complications (25.7%) as compared to controls (8.3%, p=0.01). At univariate analysis, the only risk factor for death was the occurrence of respiratory complications (OR 6.5, CI 1.8-18.2). At multivariate analysis, age >or=70 years (OR 5.36, CI 1.48-19.3) and preoperative chemotherapy (OR 7.65, CI 2.04-28.6) were confirmed as predictors of respiratory complications. Five-year survival was 17.5% in the elderly group and 53.6% in the control group (p=0.003). Elderly patients with a better respiratory function (FEV1>70%) had a 5-year survival of 45.4%. CONCLUSIONS: In the elderly patients, the risk of respiratory complications after pneumonectomy is increased as compared to younger patients with equivalent respiratory function. Age and preoperative chemotherapy are independent risk factors for respiratory complications. A lower mortality and a better long-term survival are obtained in elderly patients with a better respiratory function (FEV1>or=70%).  相似文献   
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Mariani  C.  Defendi  S.  Mailland  E.  Pomati  S. 《Neurological sciences》2006,27(1):s35-s36
Neurological Sciences - Frontotemporal dementia is a clinicopathological syndrome caused by progressive degeneration of the frontal lobes, anterior temporal lobes or both. A wide spectrum of...  相似文献   
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Bone scintigraphy plays a major role in the diagnosis of bone metastases. The clinical utility of new biochemical markers of bone metabolism has recently been investigated in various bone diseases. This study evaluated the role of some bone metabolism markers in comparison with bone scan in the follow-up of breast cancer patients. We studied 149 patients with breast cancer, 33 (22%) of whom had bone metastases. IRMAs were used for the evaluation of blood levels of osteocalcin, bone alkaline phosphatase (BAP), the C-terminal propeptide of type I procollagen and the C-terminal cross-linked telopeptide of type I collagen (ICTP). Multivariate regression analysis showed that menopausal status (P=0.007) and metastatic bone lesions (P=0.001) affected bone marker levels. When considering post-menopausal women, the only subset in which bone metabolism marker behaviour could be reliably investigated, we found a high degree of overlap in marker distribution for scan-positive and scan-negative patients. Discrimination between scan-negative and scan-positive patients based on the above markers, taken singly or jointly, was assessed by means of logistic discriminant analysis. The best discrimination was achieved with BAP, closely followed by ICTP. BAP and ICTP together gave a slight improvement over the use of the two markers separately. However, even in this case the degree of discrimination was poor and its clinical utility was limited. In fact, to achieve a specificity of 95%, the sensitivity of the test was about 20%; conversely, with a sensitivity of 95%, the specificity was below 10%. In conclusion, based on our findings, we believe that blood levels of the investigated markers cannot replace bone scintigraphy in the follow-up of breast cancer patients for the early detection of bone metastases. Received 14 April and in revised form 5 July 1997  相似文献   
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The aim of this study was to analyze the characteristics of 17 women with renal-cell carcinoma (RCC) associated with other primary neoplasms occurring in steroid-hormone target tissues. The reproductive history of these patients and the use of exogenous hormones were taken into consideration. In all, 10 RCCs were associated with breast carcinoma; 4, with endometrial carcinoma; and 3, with ovarian carcinoma. The presentation of a second primary tumor was described as synchronous or metachronous by evaluation of the interval between the discovery of the two neoplasms. Hormone and surgical treatment as well as pathologic findings for each primary tumor were also reported. In these 17 RCCs the overall rate of disease-specific survival recorded after a mean follow-up period of 32.7 months (range 9–66 months) was 58.8%; 7 patients died of metastatic disease after surviving for a mean of 14.7 months. In terms of the pathologic stage of RCC, a significant difference in mean survival was found between pN0 (mean survival 22.1 ± 3.4 months) and pN 1 RCCs (mean survival 13.7 ± 3.5 months). A total of 13 (76.4%) women were postmenopausal at the time of diagnosis of the first primary tumor; the mean age of these women at menopause was 51.7 ± 1.2 years. No prior use of oral contraceptives was reported by 12 (70.5%) of the 17 patients. Plasma 17-beta-estradiol and estrone levels were determined in only 7 patients at the diagnosis of each of the primary tumors. High plasma estrogen levels were found in 4 women with RCC and breast carcinoma and in 1 patient with RCC and endometrial carcinoma; in the remaining 2 patients low-normal values were found. A relationship appears to exist between certain reproductive and hormone-related factors and the risk of developing these tumor associations. Data emerging from the present study do not provide strong support for the hypothesis of hormone dependency of RCC; however, a role for estrogens in cases in which RCC is associated with other primary tumors involving steroid-hormone target tissues can be hypothesized.  相似文献   
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The aim of the present study was to examine the phenotypic heterogeneity of murine and human melanoma cell lines with particular reference to anticancer drug sensitivity, growth pattern and susceptibility to lysis by lymphokine (rIL2) activated killer (LAK cells). Clones selected for a different drug sensitivity were tested to evaluate the stability of such properties after different in vitro passages. A possible relationship between drug sensitivity and LAK susceptibility was also analyzed. The results indicated a high heterogeneity in murine and in human melanoma clones for all the parameters. However, drug sensitivity, which was stable although for only a few passages in an untreated human melanoma, was highly unstable in murine naturally or drug-induced resistant cells. Finally, whereas human drug-resistant clones were sensitive to lysis by LAK cells and an inverse correlation was found with the level of drug resistance, murine clones appeared to be LAK sensitive, and no correlation was found between the level of drug resistance and LAK sensitivity. Our data indicate a different stability in drug response of human and murine cells and a different behaviour of human and murine drug-resistant cells in response to LAK lysis.  相似文献   
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