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51.
Patients with acquired immunodeficiency syndrome (AIDS) are at increased risk of developing non Hodgkin's lymphomas (NHL). Current estimates indicate that 5-10% of HIV-infected individuals develop AIDS-related NHL (AIDS-NHL). AIDS-NHL share several clinical features, including frequent extranodal presentation, aggressive clinical course and poor outcome. However, AIDS-NHL are a heterogeneous group of malignancies. They traditionally included systemic and primary brain lymphomas, but nowadays their updated clinicopathologic spectrum also comprises two novel entities, namely primary effusion lymphoma and plasmablastic lymphoma of the oral cavity. In the last few years, several studies have shown that the pathologic heterogeneity of AIDS-NHL correlates with the heterogeneity of the molecular lesions associated with these lymphomas. However, despite their pathologic and molecular heterogeneity, AIDS-NHL have a common B-cell origin, although the precise stage of B-cell differentiation reflected by the different tumor types has not been clarified yet.  相似文献   
52.
Summary A combined morphological, immunohistological, and enzyme histochemical analysis was performed on frozen and fixed lymph node tissue in a case of histiocytic necrotizing lymphadenitis (HNL) using conventional histology, a panel of monoclonal and polyclonal antibodies, and a series of common haematological enzyme reactions. Histology showed multiple paracortical necrotizing foci which, in a prominently necrobiotic background devoid of granulocytes, contained large numbers of foamy histiocytes and macrophages intermingled with cells resembling degenerating plasmacytoid T-cells. Most of the histiocytes were alpha1-antichymotrypsin positive and foamy cells were also distinctly Leu-M1 positive. Strong granular acid phosphatase (AP) positivity was present in the cytoplasm of the macrophages and histiocytes. The cells with plasmacytoid features showed weaker and homogeneously diffuse AP staining. Alpha-naphthyl acetate esterase (ANAE) activity was much less striking than AP in the necrotizing foci and most of the ANAE negative cells corresponded to those with plasmacytoid features. No cells with B-cell lineage markers were present within the necrotizing foci; most of the occasional T-cells (Leu-1+, Leu-4+) present in the foci were Leu-2a+ (OKT8+) whereas OKT10+ lymphoid cells were abundant and appeared to correspond with the cells with plasmacytoid features. Our combined data confirm that the special type of necrosis found in HNL develops within foci of plasmacytoid T-cells undergoing regressive changes and apparently exhibiting distinct immunohistological and enzyme histochemical features.This study was supported in part by Grant n. 84.00525.44 from Consiglio Nazionale delle Ricerche Progetto Finalizzato Oncologia, Roma and by the Associazione Italiana per la Ricerca sul Cancro, Milano  相似文献   
53.
Kava-Kava administration reduces anxiety in perimenopausal women   总被引:1,自引:0,他引:1  
OBJECTIVE: Disturbances of mood, such as anxiety and depression, increase in the perimenopausal period. Hormone replacement therapy or neuroactive drugs represent useful treatments for these disturbances but may be contraindicated or not accepted. Herein it was investigated the efficacy of Kava-Kava, an extract of Piper Methysticum, on mood of perimenopausal women. DESIGN: A 3-months randomized prospective open study investigating in perimenopausal women modifications induced by calcium supplementation (control; n=34), calcium plus Kava-Kava at the dose of 100 mg/day (n=15) or calcium plus Kava-Kava at the dose 200 mg/day (n=19). Anxiety was evaluated by the State Trait Anxiety Inventory (STAI); depression by the Zung's scale (SDS), and climacteric symptoms by the Greene's scale. Evaluations were performed at baseline and after 1 and 3 months. RESULTS: In the control group during the 3 months, anxiety, depression and climacteric symptoms tended to decline, but not significantly. During Kava-Kava anxiety declined (P<0.001) at 1 (-3.8+/-1.03) and 3 (-5.03+/-1.2) months, depression declined at 3 months (-5.03+/-1.4; P<0.002) and climacteric score declined (P<0.0006) at 1 (-2.87+/-1.5) and 3 (-5.38+/-1.3) months. Only the decline of anxiety induced by Kava-Kava was significantly greater than that spontaneously occurring in controls (P<0.009). CONCLUSIONS: The present data indicate that, in perimenopausal women, administration of Kava-Kava induces an improvement of mood, particularly of anxiety.  相似文献   
54.
An intrauterine progesterone contraceptive system (IPCS) (52 mg) was inserted in 25 women with cystic endometrial hyperplasia. Among these women, 11 complained of heavy climacteric symptoms and also received an oestrogen replacement therapy consisting of conjugated oestrogens (0.625 mg/day) administered cyclically for 3 out of 4 wk. Prior to the therapy and after 6 mth of treatment, follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), oestrone (E1) and oestradiol (E2) plasma levels were measured and endometrial histology was evaluated. In the women receiving IPCS treatment alone, there were no significant changes in FSH, LH, PRL, E1 and E2 plasma levels. However, there were remarkable changes found in their endometrial histology. In the remaining women receiving both treatments there was a sharp decrease in FSH and LH plasma levels and an increase in E1 and E2 plasma levels, while the prolactin levels remained unchanged. With the exception of two of these women, the endometrial histology changed remarkably. The endometrial morphology of the two exceptions remained unchanged. All climacteric symptoms disappeared after the administration of both IPCS and the oestrogen replacement therapy. The remarkable changes which did occur in the endometrial histology resulted in a less active glandular epithelium and stromal decidual formation, thus proving a useful effect of treatment.  相似文献   
55.
Cytotoxicity, morphological neoplastic transformation, cellularuptake and metabolic reduction were determined in BALB/3T3 CIA31-1-1 cells for trivalent arsenic (sodium arsenite, As3+)and for pentavalent arsenic (sodium arsenate, As5+). The levelsof cellular uptake of73As-labelled sodium arsenite and arsenatewere dose-dependent and highest in the first hour. At equimolarconcentration (3 x 10–6 M), cellular uptake was 4-foldhigher for As3+ than for As5+. Cytotoxicity was higher for As3+than for As5+, but when correlated to total As cell burden itshowed no significant difference for the two forms. Morphologicaltransformation focus assays showed transforming activity forboth As3+ and As5+, with relative transformation frequenciesalso of 4:1. Recovery from the cytosol after exposure for 1–24h was >90% for either form of absorbed As. Exposure to As3+yielded 100% as As3+ in cytosol, but exposure to As5+ yielded>70% as As3+, showing a high rate of intracellular metabolicreduction. No methylated metabolites were detected by ion-exchangechromatography. After 24-h incubation in cell-free medium, oxidationof As3+ to As5+ occurred up to 30% of the dose, but incubationin the presence of cells lowered the oxidation level to 4%.As5+ was recovered unchanged from cell-free medium (24-h incubation),but in the presence of the cells it yielded up to 5% as As3+within 24 h and the cumulative release of As3+ by cells exposedto As5+ was dose-dependent. Glutathione depletion by diethylmaleateinhibited reduction of As5+ to As3+ by these cells up to 25%of controls, showing that As5+ reduction is partly dependenton glutathione. These results suggest that As3+ is the formresponsible for the cytotoxic and transforming effects, independentlyof the valence state of the inorganic arsenic in the culturemedium.  相似文献   
56.
Liver transplantation (LT) for colorectal liver metastasis (CRLM) may provide excellent survival rates in patients with unresectable disease. High tumor load is a risk factor for recurrence and low overall survival (OS) after liver resection (LR). We tested the hypothesis that LT could offer better survival than LR in patients with high tumor load. LR performed at Padua University Hospital for CRLM was compared with LT for unresectable CRLM performed both at Oslo and Padua. High tumor load was defined as tumor burden score (TBS) ≥ 9, and inclusion criteria were as in the SECA-I transplant study. 184 patients were eligible: 128 LRs and 56 LTs. 5-year OS after LR and LT was 40.5% and 54.7% (= 0.102). In the high TBS cohort, 5-year OS after LR and LT was 22.7% and 52.2% (P = 0.055). In patients with Oslo score ≤ 2 and TBS ≥ 9 (13 LR; 24 LT) the 5-year OS after LR and LT was 14.6% and 69.1% (P = 0.002). The corresponding disease-free survival (DFS) was 0% and 22.9% (P = 0.005). Selected CRLM patients with low Oslo score and high TBS could benefit from LT with survival outcomes that are far better than what is achieved by LR.  相似文献   
57.
58.
Introduction:Due to the COVID-19 pandemic, healthcare workers are now required to use additional personal protective equipment (PPEs) to protect themselves against the virus. That led to an increased clothing insulation which is negatively affecting the perceived healthcare workers’ thermal sensation.Objectives:While demonstrating through software simulations the potential level of thermal discomfort healthcare workers involved in the COVID-19 emergency can be subjected to, this work aims at identifying measures to improve thermal sensation perception and acceptable thermal conditions for medical personnel.Methods:After having obtained the insulation values of individual clothing used by staff during COVID-19 emergency through the use of a thermal well-being evaluation software, the Fanger indexes (PMV - Predicted Mean Vote and PPD - Predicted Percentage of Dissatisfied) were calculated in order to estimate staff satisfaction to microclimatic conditions.Results:The use of COVID-19 additional PPEs with an air temperature equal to 22 °C (normally considered optimal) brings the PMV index equal to 0.6, which corresponds to 11.8 % being unsatisfied (PPD) due to perceived heat.Discussion:The use of additional protective devices significantly increases the clothing insulation level, facilitating the onset of conditions of thermal discomfort in the health workers. Workers engaged in the execution of nasopharyngeal swabs were most affected by the summer weather conditions and certainly represent the most critical category, for which it would be recommended to implement a higher turnover of service to reduce individual exposure time and consequent discomfort.  相似文献   
59.
We describe the association of brain death in an infant with a large cutaneous hemangioma of the forearm. The irreversible cerebral injury is presumed to be secondary to cerebral hypoperfusion as a result of a combination of systemic hypotension and a systemic vascular "steal" phenomenon caused by the cutaneous hemangioma.  相似文献   
60.
Summary The clinical pharmacokinetics of 4-demethoxydaunorubicin was investigated in 28 cancer patients who received the drug orally. The majority of the patients were elderly (median age, 72 years). Nine of them also received an i. v. dose, and the bioavailability of the oral dose ranged between 9% and 39%. 4-Demethoxydaunorubicin peak levels were achieved 2–4 h after the oral dose in most patients. The drug was rapidly and extensively metabolized to 4-demethoxy-13-hydroxydaunorubicin, which is probably as active as the parent drug. The metabolite levels were much higher and longer lasting than the parent drug, suggesting that it may play an important role in the drug's pharmacological effects.  相似文献   
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