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81.
B Salvadori  M Greco  A R Conti 《Tumori》1979,65(3):279-288
The surgical approach to minimal breast cancer is still under discussion. In fact by the term "minimal" three lesions are meant, namely "lobular carcinoma in situ", "intraductal carcinoma" and invasive "microcarcinoma". It is really difficult to indicate appropriate treatment for these tumors, also because the series reported in the literature are few and represented by a small number of cases. The present paper is a critical review of the literature on the subject. According to the most recent view lobular carcinoma in situ and intraductal carcinoma demand for radical surgery (total mastectomy) due to the high percentage of multicentricity and bilaterality of these lesions. More particularly with regard to lobular carcinoma in situ recent reports claim for a "wait and see" policy which is gaining favour, on the ground that the risk of developing invasive cancer in women with lobular carcinoma in situ is not so high and that the period of time between diagnosis of the lobular carcinoma and the development of the invasive cancer is usually very long. On the other side, for intraductal carcinoma, axillary dissection seems to be pleonastic due to the low percentage of secondary deposits in axillary lymph-nodes (1-3%) in women operated on for intraductal carcinoma. Invasive microcardinomas, less than 5 mm in diameter, should be considered as T1N0 tumors; actually there is no reason to treat them by a more conservative surgery than is done for T1N0 cancers, as they present the same involvement of the axillary lymph nodes. In a small series of 38 microcarcinoma observed at the Milan Cancer Institut N+ cases were 27%.  相似文献   
82.
The levels of 2 arachidonic acid metabolites formed either by enzymatic activity of cyclooxygenase, i.e. prostaglandin E2 (PGE2), or by free radical-catalyzed peroxidation, i.e. F2-isoprostane 8-epi-prostaglandin F2alpha (8-epi-PGF2alpha), were measured in the CSF of subjects with sporadic and familial Creutzfeldt-Jakob disease (CJD) and in brain homogenates of scrapie-infected mice. The CSF levels of both metabolites were increased in sporadic CJD (n = 52) and familial CJD (n = 10) patients when compared with a group of patients with noninflammatory disorders. Similarly, PGE2 and 8-epi-PGF2alpha levels were higher in brain homogenates obtained from C57BL/6J mice infected with the ME7 scrapie strain than in brain homogenates from control animals. As PGE2 is 1 of the most abundant prostaglandins released during inflammation and 8-epi-PGF2alpha is a quantitative marker of lipid peroxidation, our results provide in vivo biochemical evidence for the occurrence of inflammation and oxidative stress in human and experimental transmissible spongiform encephalopathies (TSEs), a concept so far based mainly on histopathological and in vitro evidence. Interestingly, in sporadic CJD patients, high CSF levels of PGE2, but not 8-epi-PGF2alpha, correlated with short survival time, suggesting that the inflammatory response correlates with the clinical duration of disease.  相似文献   
83.
BACKGROUND: In rodents, CsA has been shown to affect T-cell development, giving rise to an abnormal production of mature T cells and the absence of many T-cell subsets as well as to autoimmunity. Surprisingly, only a few studies investigated the effect of the immunosuppressive drug on the immune system of the human fetus. METHODS: We examined six infants born to female kidney transplant recipients who had received cyclosporine and methylprednisolone throughout their pregnancies. Peripheral blood was obtained 1 day and 2, 4, 6, and 12 months after birth, and two-color flow cytometric immunophenotyping of lymphocytes was performed. RESULTS: Total T cells, as well as CD4+ and CD8+ T cells, were low at birth, but normalized thereafter. Among T-cell activation markers, the expression of CD25, the alpha chain of the interleukin-2 receptor, was below the normal range or low range throughout the study period, and HLA-DR expression was extremely low at birth and failed to increase up to 12 months. The number of total B cells was lower than normal at birth, but steeply increased over time. In contrast, B-cell subset bearing CD5 antigen was severely depleted throughout the first year of life. Total IgG concentration was significantly lower than in controls at 2 months, mainly because of subnormal levels of IgG1 and IgG3 subclasses, which remained in the low range up to 6 months. Finally, infants showed normal numbers of true natural killer (NK) cells (CD3-CD16+CD56+), whereas the expression of CD57 antigen, defining non-MHC-restricted cytotoxic lymphocytes, was barely detectable at birth and failed to increase over time, in both CD8+ and CD8- subsets. Of note, none of the infants had clinical evidence of an immunodeficient state. CONCLUSIONS: continuous exposure to CsA in utero seemingly impairs T-, B-, and NK-cell development and/or maturation, and most of its effects are still apparent at 1 year, which might suggest that conventional vaccinations should be delayed in these infants.  相似文献   
84.
OBJECTIVE. We evaluated the extent to which hepatic lesion characterization and detection is improved by using gadobenate dimeglumine for enhancement of MR images. MATERIALS AND METHODS. Eighty-six patients were imaged before gadobenate dimeglumine administration, immediately after the 2 mL/sec bolus administration of a 0.05 mmol/kg dose (dynamic imaging), and at 60-120 min after the IV infusion at 10 mL/min of a further 0.05 nmol/kg dose (delayed imaging). The accuracy for lesion characterization was assessed for a total of 107 lesions. Sensitivity for lesion detection was assessed for a total of 149 lesions detected on either intra-operative sonography, iodized oil CT, CT during arterial portography, or follow-up contrast-enhanced CT as the gold standard. RESULTS. The accuracy in differentiating benign from malignant liver lesions increased from 75% and 82% (the findings of two observers) on unenhanced images alone, to 89% and 80% on dynamic images alone (p<0.001, p = 0.8), and to 90.7% when combining the unenhanced and dynamic image sets (p<0.001, p = 0.023). Delayed images did not further improve accuracy (90% and 91%; p = 0.002, p< 0.05). A similar trend was apparent in terms of accuracy for specific diagnosis: values ranged from 49% and 62% on unenhanced images alone, to 76% and 70% on combined unenhanced and dynamic images (p<0.001, p = 0.06), and to 75% and 70% on inclusion of delayed images (p<0.001, p = 0.12). The sensitivity for lesion detection increased from 77% and 81% on unenhanced images alone, to 87% and 85% on combined unenhanced and dynamic images (p = 0.001, p = 0.267), and to 92% and 89% when all images were considered (p<0.001, p = 0.01). CONCLUSION. Contrast-enhanced dynamic MR imaging with gadobenate dimeglumine significantly increases sensitivity and accuracy over unenhanced imaging for the characterization of focal hepatic lesions, and delayed MR imaging contributes to the improved detection of lesions.  相似文献   
85.
In the last 10 years, four patients with aneurysms of the supraaortic trunks and the internal carotid artery have been operated in emergency at Department of Vascular Surgery of University of Bari. The first case was a mycotic aneurysm of the carotid bifurcation, the second an aneurysm of internal carotid artery interesting the retropharynx, the third a post-operatory pseudoaneurysm of common carotid in a patient affected by Takayasu's disease and the last an atherosclerotic aneurysm of the innominate artery. Clinical picture suggested an immediate surgical treatment in all patients. Different procedure were used depending on size and localization of each lesion. Results in all cases have been satisfactory. The aneurysms of supraaortic trunks and of internal carotid artery are very rare; therefore when clinical picture is dramatic or quickly worsening, emergency treatment is mandatory in order to reduce mortality risk and minimize complications.  相似文献   
86.
87.
Xerophilic fungal species of the genus Aspergillus are economically highly relevant due to their ability to grow on low water activity substrates causing spoilage of stored goods and animal feeds. These fungi can synthesize a variety of secondary metabolites, many of which show animal toxicity, creating a health risk for food production animals and to humans as final consumers, respectively. Animal feeds used for rabbit, chinchilla and rainbow trout production in Argentina were analysed for the presence of xerophilic Aspergillus section Aspergillus species. High isolation frequencies (>60%) were detected in all the studied rabbit and chinchilla feeds, while the rainbow trout feeds showed lower fungal charge (25%). These section Aspergillus contaminations comprised predominantly five taxa. Twenty isolates were subjected to taxonomic characterization using both ascospore SEM micromorphology and two independent DNA loci sequencing. The secondary metabolite profiles of the isolates were determined qualitatively by HPLC-MS. All the isolates produced neoechinulin A, 17 isolates were positive for cladosporin and echinulin, and 18 were positive for neoechinulin B. Physcion and preechinulin were detected in a minor proportion of the isolates. This is the first report describing the detailed species composition and the secondary metabolite profiles of Aspergillus section Aspergillus contaminating animal feeds.  相似文献   
88.
89.
90.
This work is aimed to present an innovative technology for the reinforcement of beams for urban furniture, produced by in-mold extrusion of plastics from solid urban waste. This material, which is usually referred to as “recycled plastic lumber”, is characterized by very poor mechanical properties, which results in high deflections under flexural loads, particularly under creep conditions. The Prowaste project, founded by the EACI (European Agency for Competitiveness and Innovation) in the framework of the Eco-Innovation measure, was finalized to develop an innovative technology for selective reinforcement of recycled plastic lumber. Selective reinforcement was carried out by the addition of pultruded glass rods in specific positions with respect to the cross section of the beam, which allowed optimizing the reinforcing efficiency. The reinforcement of the plastic lumber beams with pultruded rods was tested at industrial scale plant, at Solteco SL (Alfaro, Spain). The beams obtained, characterized by low cost and weight, were commercialized by the Spanish company. The present paper presents the most relevant results of the Prowaste project. Initially, an evaluation of the different materials candidates for the reinforcement of recycled plastic lumber is presented. Plastic lumber beams produced in the industrial plant were characterized in terms of flexural properties. The results obtained are interpreted by means of beam theory, which allows for extrapolation of the characteristic features of beams produced by different reinforcing elements. Finally, a theoretical comparison with other approaches which can be used for the reinforcement of plastic lumber is presented, highlighting that, among others, the Prowaste concept maximizes the stiffening efficiency, allowing to significantly reduce the weight of the components.  相似文献   
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