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The spleen can be affected by several different non-hematopoietic neoplasms as well as pseudoneoplastic lesions. Generally such conditions affect asymptomatic adults and are detected only as incidental findings; in a minority of the cases vague, unspecific symptoms including abdominal discomfort can occur. Most of these conditions present as a “solitary splenic mass” and have been traditionally diagnosed on partial or total splenectomy, which also represents the most common therapeutic strategy; however, the increasing use of splenic needle biopsies for such lesions creates new diagnostic challenges for pathologists. Splenic cysts (including true cysts, pseudocysts and parasitic cysts) and hamartomas are common benign proliferations which generally pose little problems in their identification. More challenging is the diagnostic workup of “spindle cell and inflammatory rich” lesions of the spleen, whose correct identification is crucial. Indeed, some of these are considered reactive (such as sclerosing angiomatoid nodular transformation of the spleen), whilst others are clonal in nature, the main example being represented by the so called “inflammatory pseudotumour- like follicular/fibroblastic dendritic cell sarcoma”. A further degree of complexity is represented by the detection of the Epstein-Barr virus (EBV), which is invariably present in inflammatory pseudotumour- like follicular/fibroblastic dendritic cell sarcoma, but also in other proliferations including the rare “EBV- related smooth muscle tumor of the spleen”. Finally, the spleen can host rare dendritic/reticulum cell sarcomas and metastases from extrasplenic malignancies. The current review aims at highlighting the main histologic features of non-hematopoietic and non-vascular neoplasms as well as pseudoneoplastic lesions of the spleen.  相似文献   
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Button batteries are easily swallowed by children and may produce severe digestive injuries through two different mechanisms: electrochemical burns when in contact with the digestive mucosa, release of caustic substances when fragmented. Esophageal lesions are especially dangerous, as they can lead to perforation, fistula or secondary stenosis. The risk of mercury intoxication is less worrying since the assimilated fraction of the metal is unlikely to produce clinical effect. Although the large majority of the reported cases of button battery ingestion remained asymptomatic, the potentially lethal outcome justifies a precise diagnostic procedure: any button battery ingestion must be documented with a radiography of the digestive tract. Any battery lodged in the esophagus must be urgently removed by endoscopy. Other locations do not need any removal attempt unless complications: nonetheless a follow-up is necessary to confirm the spontaneous elimination of the battery. Manufacturers, physicians and parents share responsibility for preventing such accidents.  相似文献   
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Summary Fatigue of the vastus lateralis muscle was studied in healthy well-conditioned students, who differed considerably regarding their muscle fibre type distribution. Muscle force decline during repeated maximum voluntary knee extensions at a constant angular velocity (180×s–1 or rad×s–1), using isokinetic equipment, was taken as the criterion for the degree of fatigue. In an attempt to study quantitative as well as qualitative changes in the EMG pattern, integrated EMG (IEMG) and the frequency of the mean power (MPF), computed from the power spectral density function (PSDF), were analysed. It was found that individuals with muscles made up of a high proportion of fast twitch (FT) muscle fibres demonstrated higher peak knee extension torque, and a greater susceptibility to fatigue than did individuals with muscles mainly composed of slow twitch (ST) muscle fibres. An IEMG decline (p<0.01) was demonstrated during 100 contractions in individuals rich in FT fibres. Only a slight, but not significant, reduction in IEMG occurred in individuals with a high percentage of ST fibres. Concomitantly, MPF decreased (p<0.001) in individuals with a high percentage of FT fibres, while their opposites demonstrated only a slight decrease (non-significant). It is suggested that muscle contraction failure might also be related to qualitative changes in the motor unit recruitment pattern, and that these changes occur more rapidly in muscles composed of a high proportion of FT muscle fibres than in muscles composed of a high proportion of ST fibres.  相似文献   
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OBJECTIVES: To compare health related quality of life (HRQL) between native and immigrant adolescents aged 12 to 18 years, and to analyse psychosocial factors associated with HRQL. DESIGN: A cross sectional study of adolescents (12-18 years old) who answered a self administered questionnaire. SETTING: All the secondary schools from Lloret de Mar (Girona, Spain). PARTICIPANTS: 1246 participants (88.9% of the eligible students). MAIN OUTCOME MEASURES: Main outcome was the Spanish version of the Vecu et Sante Percue de l'Adolescent (VSP-A), a HRQL measure addressed to adolescents. Mean scores of the VSP-A index of natives and immigrants were compared, as well as their sociodemographic and health related factors. Multiple regression examined the relation between HRQL and psychosocial factors, controlling for the effect of socioeconomic variables. RESULTS: Half of the sample were boys, in the middle socioeconomic status, and 18.2% were immigrants (n = 226). HRQL score was higher in native Spanish adolescents than immigrants (p<0.01). Multiple regression model explaining 48.1% of the VSP-A variance showed that migration in itself has no statistically significant impact on HRQL, and age, socioeconomic status, social support, discrimination, and psychological distress do play a part. CONCLUSIONS: Migrants have worse HRQL than natives but it seems to be mediated by their disadvantage in socioeconomic status, social support, and psychological distress.  相似文献   
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BACKGROUND: Allograft tolerance might be achieved by expressing immunomodulatory proteins through gene therapy. We have evaluated the possibility of promoting significantly allograft survival in a vascularized cardiac allograft model by performing ex vivo gene transfer. We used a lentiviral vector encoding the chemokine antagonist RANTES 9-68 that is capable of competing with native RANTES. METHODS: The Fisher donor/Lewis recipient rat strain combinations were used and all animals received for the first 5 days posttransplantation a subtherapeutic dose of cyclosporine A (1.5 mg/kg). Ex vivo gene transfer into heart allograft was performed by multiple injections of the SIN.cPPT lentiviral vector, which corresponds to the multiply attenuated, self-inactivating lentivector derived from the human immunodeficiency virus (HIV)-1. RESULTS: About 6% of the cardiac tissue had integrated lentiviral vector, which closely matches the mean in vivo RANTES antagonist expression of 5% obtained by immunohistochemistry. In vivo RANTES 9-68 expression has significantly prolonged graft survival (median [25%-75%]: 20 [17-26] days), compared to the control 15 ([14-15] days; P=0.0007). Furthermore, hearts transduced with RANTES 9-68 showed a significant (P<0.05) reduction in cell infiltration and intragraft expression of TNF-alpha, IFN-gamma, endogenous RANTES, and TGF-beta. CONCLUSION: Lentiviral gene transfer of RANTES 9-68 antagonist attenuates significantly the inflammatory response and delays allograft rejection, despite low levels of transduction. Future improvement of heart transduction by lentiviral vectors, as it has been achieved with other vectors, might become an attractive alternative therapy for treating allografts that require sustained gene expression for better organ preservation.  相似文献   
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