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81.
Journal of Thrombosis and Thrombolysis - Low dose enteric-coated aspirin (EC-ASA) is routinely used for secondary cardiovascular event prevention. However, absorption of EC tablets is poor, which...  相似文献   
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The aim of this study was to examine the possible relationship between the plasma levels of leptin and tumor necrosis factor (TNF)- and the stage of hepatic fibrosis in a cohort of patients with chronic hepatitis C. Leptin and TNF levels were measured by RIA in 135 patients and in 75 age- and sex-matched controls. Liver disease was evaluated by the stage of fibrosis and the extent of inflammatory infiltrate in the liver biopsy. Leptin levels correlated with BMI values in healthy controls and in patients with chronic hepatitis C (men, r = 0.61, P = 0.0001; women, r = 0.68, P = 0.003). Leptin levels increased as hepatic fibrosis stage progressed both in male and in female patients (P < 0.001); also, TNF levels were higher in patients with an advanced stage of fibrosis (P = 0.006). In these patients, levels of leptin increased according to the progression of the stage of fibrosis; these data suggest that leptin may play a role in the regulation of hepatic fibrosis.  相似文献   
85.
In 80 patients with Ph-positive chronic myelogenous leukaemia the main clinical, haematological and cytogenetical data were recorded at diagnosis of blast crisis and evaluated for prognostic significance. At the time of the analysis 73 patients had died, with a median survival of 4-8 months from diagnosis of blast crisis for the whole series. When analysed as a time-dependent variable, the achievement of a favourable response to chemotherapy resulted in a longer patient's survival. On the other hand, the univariate analysis identified six pretreatment characteristics associated with a poorer prognosis: a longer chronic phase, presence of extramedullary blastic involvement, a platelet count below 200 x 10(9)/l, a less marked leucocytosis, a blood blast cell percentage higher than 10%, and presence of trisomy 8. The latter parameters were included in a multiple regression model together with the blast cell phenotype (lymphoid versus non-lymphoid), and only four of them (trisomy 8, duration of chronic phase, platelet count, and leucocyte count) retained their prognostic influence. When the therapeutical response was also included in the regression model, it proved to be the most important prognostic variable, followed by trisomy 8, length of chronic phase, extramedullary disease, and platelet count, whereas the leukocyte count lost its predictive value. Thus, in spite of the short overall survival of blast crisis patients, the identification of prognostic factors in such a haematological condition may be of interest, especially in the interpretation of new therapeutical approaches.  相似文献   
86.
We have analyzed 117 younger patients with chronic lymphocytic leukemia (CLL) (mean age, 44.5 years; SD, 4.8; range, 19 to 49; male/female ratio, 2.08) with three main objectives: (1) to see whether these patients have distinctive presenting clinical features; (2) to investigate the impact of the disease on survival; and (3) to analyze whether already well-known prognostic factors are also useful when applied to these patients. As compared with an older age population (greater than or equal to 50 years), there were no major differences in presenting features except for an increased proportion of males (2.08 v 1.21; P less than .025) and a higher hemoglobin level (13.47 +/- 2.70 g/dL v 12.84 +/- 2.77 g/dL; P less than .05) in the younger group. Median survival is 12.3 years (expected median from a control group, 31.2 years). Clinical stages, bone marrow patterns, blood lymphocyte counts, and its doubling time are all useful to separate different risk groups of patients. Whereas patients with favorable prognostic factors have a survival probability of about 80% 14 years after diagnosis, those with poor prognostic features have a median survival of less than 3 years. It is concluded that CLL in younger adults has no major distinctive presenting features and that known prognostic factors are useful to separate different risk groups of patients. These results should be of help in planning therapy for younger persons with CLL.  相似文献   
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BACKGROUND: Few studies have assessed the relationship between ambulatory blood pressure (BP) and cardiac damage in essential hypertensive patients with inverse white coat hypertension (IWCH). OBJECTIVES: To determine the frequency of IWCH in untreated grade 1-2 hypertension and to assess possible differences in cardiac damage among patients with IWCH, white coat hypertension (WCH) and the rest of patients with grade 1-2 hypertension. PATIENTS AND METHODS: Two hundred and eleven patients with grade 1-2 hypertension were sequentially included. A good quality 24-h ambulatory BP monitoring was obtained in 204 patients (age: 41 +/- 12 years, 56% males). IWCH was defined as a daytime systolic and/or diastolic BP higher than diagnostic office systolic and/or diastolic BP, respectively. WCH was defined as a daytime BP < 135/85 mmHg. A good quality echocardiogram was obtained in 174 patients. We considered left ventricular hypertrophy a left ventricular mass index (LVMI) > or = 125 g/m2. RESULTS: We found IWCH in 29 subjects (14%), and WCH in 68 (33%). Office BP in patients with IWCH was in an intermediate position between WCH and the rest of grade 1-2 hypertension patients. The IWCH patients showed 24-h, daytime and night-time BP higher than the other groups. Left ventricular mass was significantly greater in patients with IWCH than in the other grade 1-2 hypertension patients after adjusting for age, gender, body mass index, smoking and office BP (regression coefficient 28.14, 95%CI: 7.36-48.91). CONCLUSION: IWCH is independently associated with higher values of left ventricular mass in patients with grade 1-2 hypertension.  相似文献   
89.
Sphingolipids (SLs) comprise a class of lipids with important structural functions and increasing relevance in cellular signalling. In particular, ceramide has attracted considerable attention owing to its role as a second messenger modulating several cell functions such as proliferation, gene expression, differentiation, cell cycle arrest and cell death. Increasing evidence documents the role of SLs in stress and death ligand-induced hepatocellular death, which contributes to the progression of several liver diseases including steatohepatitis, ischaemia-reperfusion liver injury or hepatocarcinogenesis. Furthermore, recent data indicate that the accumulation of SLs in specific cell subcompartments, characteristic of many sphingolipidoses, contributes to the hepatic dysfunctions that accompany these inherited diseases. Hence, the regulation of the cell biology and metabolism of SLs may open up a novel therapeutic avenue in the treatment of liver diseases.  相似文献   
90.
Major histocompatibility complex class II (MHC‐II) molecules bind to and display antigenic peptides on the surface of antigen‐presenting cells (APCs). In the absence of infection, MHC‐II molecules on APCs present self‐peptides and interact with CD4+ T cells to maintain tolerance and homeostasis. In the thymus, self‐peptides bind to MHC‐II molecules expressed by defined populations of APCs specialised for the different steps of T‐cell selection. Cortical epithelial cells present peptides for positive selection, whereas medullary epithelial cells and dendritic cells are responsible for peptide presentation for negative selection. However, few data are available on the peptides presented by MHC molecules in the thymus. Here, we apply mass spectrometry to analyse and identify MHC‐II‐associated peptides from five fresh human thymus samples. The data show a diverse self‐peptide repertoire, mostly consisting of predicted MHC‐II high binders. Despite technical limitations preventing single cell population analyses of peptides, these data constitute the first direct assessment of the HLA‐II‐bound peptidome and provide insight into how this peptidome is generated and how it drives T‐cell repertoire formation.  相似文献   
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