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31.
Flow-cytometric detection of minimal residual disease (MRD) identifies patients with high relapse risk in childhood acute lymphoblastic leukaemia (ALL). We studied the efficacy of this method in adult T-ALL treated with the Italian co-operative GIMEMA (Gruppo Italiano Malattie Ematologiche dell'Adulto) LAL0496 protocol. Bone marrow samples from 53 patients were taken at fixed treatment time points and MRD was analysed using a leukaemia-specific immunophenotype (cytoplasmic-CD3/nuclear-terminal desoxynucleotidyl transferase). The median follow-up was 17 months (range 3-61) and a median of 4.5 analyses/patient was performed (range 3-12). Six out of 53 (11.3%) patients were refractory to treatment, 30/53 (56.6%) relapsed and 17/53 (32.1%) remain in continuous complete remission. The probability of relapse at 2 years for MRD-positive patients at preconsolidation was 81.5%vs 38.9% for MRD-negative patients (P = 0.00078). This risk was still 54.5% for MRD-positive vs 15.8% for MRD-negative patients pre-third reinduction (P = 0.0098) and 50.0% for MRD-positive vs 16.4% for MRD-negative patients pre-sixth reinduction (P = 0.032). The relapse-predicting value of MRD did not depend on features at diagnosis such as age, sex and leucocyte count. Our data suggest that immunophenotypic MRD monitoring in the first year of treatment is a useful outcome predictor for adult T-ALL patients.  相似文献   
32.
Despite the availability of all advanced diagnostic tools, fever of unknown origin (FUO) remains a diagnostic challenge for physicians. The objective was to define, through a retrospective study, the categories of the diseases of Sicilian patients admitted at the Department of Clinical Medicine and Emerging Diseases, University of Palermo, Italy, for classical FUO. Using the registration system for patients admitted from 1991 to 2002, 508 charts of patients admitted because of fever were reviewed. Of these, only 91 patients fulfilled the criteria for classical FUO. The origin of FUO was diagnosed in 62 (68.1%) patients. Infection was the most common cause of FUO with 29 cases (31.8% of total of FUO), neoplasms accounted for 13 cases (14.2%), collagen vascular disease for 11 cases (12.0%), and miscellaneous for 9 cases (9.8%). Undiagnosed FUO were 29 (31.8%) and, of them, 22 cases were followed-up for 2 years. A definite diagnosis could be established only in 8 cases, 13 subjects completely recovered and 4 of them died. In the 73.4% of cases, the FUO have been the result of misleading factors in the diagnostic approaches as made by the physician. The results of our study are similar to those already reported by other authors in other populations, with infections as first, neoplasm as second, and collagen vascular diseases as third most important causes of FUO. In our study the prognosis for undiagnosed FUO cases was good, but a definite diagnosis could be established only in few cases. Therefore, further multicentric, prospective studies of good design are required.  相似文献   
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Guardianship may pose an ethical dilemma for physicians, who must balance protecting vulnerable patients from potential safety concerns with respecting their autonomy. Older adults with dementia are particularly susceptible to loss of independence and the ability to participate in medical decision making. To have the capacity for medical decision making, individuals must understand relevant information, appreciate their circumstances, demonstrate reasoning, and express a consistent choice free from coercion. Although capacity assessments are usually task-specific, geriatricians and other specialists may be asked to comment on capacity more globally. These determinations may be used to support a Petition for the Appointment of a Guardian of a Legally Incapacitated Adult, the legal process of pursuing guardianship in probate court. Assigned guardians may be known to the incapacitated individual (e.g., a family member or friend) or may be professional guardians with no prior relationship to the ward. Guardians are encouraged to use substituted decision-making, taking into account the ward's previously expressed values and preferences. Although a number of viable alternatives to guardianship exist, numerous systemic barriers may prevent these from being fully explored. The ongoing need for guardianship should be periodically revisited and reassessed. Data about guardians and wards is shockingly sparse, as there are no centralized databases. Laws and regulations for guardianships vary significantly between states. Physicians can serve as important allies and advocates for patients with cognitive impairment at risk of incapacity, can help preserve their autonomy for as long as possible, and ensure appropriate protections are in place if the patient does lose their decision-making ability.  相似文献   
35.
Serum levels of lipids, lipoproteins and apolipoproteins A-I and B were evaluated in 102 patients (75 males and 27 females; ages 58 +/- 8 and 61 +/- 7 years (mean +/- SD), respectively) with arteriosclerosis of the lower limbs of supra-aortic trunks. Compared to findings in 64 healthy, age-matched control subjects, male patients in both groups had significantly higher serum triglyceride levels (+42%, P less than 0.05), while female patients with lower limb arteriosclerosis showed significantly increased cholesterol and triglyceride concentrations (+19%, P less than 0.01 and +82%, P less than 0.05, respectively). LDL-triglycerides were also increased in all patients. HDL-cholesterol was significantly decreased in male patients with arteriosclerosis of the lower limbs (-27%, P less than 0.01) and the supra-aortic trunks (-28%, P less than 0.01), and in females of both groups (-26%, P less than 0.01 and -20%, P less than 0.01, respectively); in terms of percent, HDL2-cholesterol was reduced 2-fold compared to HDL3-cholesterol. Patient apolipoprotein A-I and B levels were unchanged. In male and female patients, correlations between triglycerides and HDL-cholesterol as well as HDL2-cholesterol were negative, but not significant; on the other hand, both correlations were negative and significant in male controls, while only the correlation between triglycerides and HDL2-cholesterol was negative and significant in the female controls. Since HDL-cholesterol, and in particular HDL2-cholesterol, concentrations seem closely related to the intravascular catabolism of triglyceride-rich lipoproteins, the absence of a significant correlation between these parameters in the patients suggests a possible alteration in this metabolic process.  相似文献   
36.
BACKGROUND AND AIM OF THE STUDY: Thromboembolism and hemorrhage related to anticoagulation remain a major concern in elderly patients with mechanical valves. Clinical results following isolated aortic valve replacement (AVR) with tilting disk and bileaflet prostheses in patients aged over 70 years were analyzed and compared with results in patients aged <45 years. METHODS: Between January 1980 and August 2002, 319 consecutive older patients (group A) and 497 young patients AVR. Preoperative clinical data, early and late mortality, valve-related complications and data related to anticoagulation status (including mean INR and mean interval between INR assays) were compared between groups. RESULTS: Hospital mortality was lower in group B (3.4%) than in group A (10.7%; p <0.0001). Twelve-year actuarial survival was lower in older patients (54% in group A versus 78% in group B; p <0.001). The two groups showed similar 12-year actuarial freedom from hemorrhage (99.6% versus 99.5%; p = 0.69), endocarditis (99.6% versus 98.43%; p = 0.25) and perivalvular leak (99.6% versus 97.9%; p = 0.21). However, actuarial freedom from thromboembolism was lower in older patients (98.8% versus 99.7%; p = 0.041). CONCLUSION: Despite lower rates of long-term mortality and thromboembolism (the latter because of advanced atherosclerosis) in group A, there were no differences in rates of other valve-related complications. Hence, older age cannot be considered a contraindication to implantation of mechanical valves in the aortic position.  相似文献   
37.
Mammalian megakaryocyte development is characterized by a progressive accumulation of cells exhibiting a polylobated nucleus with a polyploid DNA content. In this study human megakaryocytes were obtained from CD34+ haemopoietic progenitors by in vitro liquid culture in the presence of 100 ng/ml of recombinant thrombopoietin (TPO). Ultrastructural examination of polyploid megakaryocytes showed the presence of a large number of centrioles, the breakdown of the nuclear envelope, and the progressive chromatin condensation, all aspects characteristic of mitosis. At both indirect immunofluorescence and Western blot analyses, cyclin B and its related cyclin-dependent kinase (CDK)1, which forms the mitosis promoting factor (MPF), showed an increased expression in maturating megakaryoblasts and megakaryocytes (day 8 of culture) with respect to freshly isolated CD34+ progenitors. This expression tended to decline in fully developed megakaryocytes (day 15 of culture). The amount of cyclin D and of the related CDK4, governing the G1 phase of the cell cycle, increased during megakaryocyte development, maintaining high levels of expression also in mature megakaryocytes. These results indicate that megakaryocyte polyploidization depends on a true, although incomplete, mitotic process, and that cyclin D/CDK4 probably plays a crucial role throughout megakaryocytopoiesis.  相似文献   
38.
Chronic hepatitis C virus (HCV) infection is the principal etiology of cirrhosis and, ultimately, hepatocellular carcinoma (HCC). At present, approximately 71 million people are chronically infected with HCV, and 10%–20% of these are expected to develop severe liver complications throughout their lifetime. Scientific evidence has clearly shown the causal association between miRNAs, HCV infection and HCC. Although it is not completely clear whether miRNA dysregulation in HCC is the cause or the consequence of its development, variations in miRNA patterns have been described in different liver diseases, including HCC. Many studies have analyzed the importance of circulating miRNAs and their effect on cell proliferation and apoptosis. In this Review, we aim to summarize current knowledge on the association between miRNA, HCV and HCC from a diagnostic point of view, and also the potential implications for therapeutic approaches.  相似文献   
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BACKGROUND/AIMS: Prognosis assessment in patients with hepatocellular carcinoma (HCC) remains controversial. The most widely used HCC prognostic tool is the Okuda classification, but new staging systems (Cancer of the Liver Italian Program score, Chinese University Prognostic Index, French classification and Barcelona Clinic Liver Cancer, BCLC, staging) have been recently described. We investigated the value of known prognostic systems in the particular setting of a surgically oriented Liver Unit where 187 HCC Italian patients were mainly treated with radical therapies (resection and percutaneous ablation). METHODS: A retrospective analysis of 187 HCCs observed at a single Institution from 1990 and 1999 was performed. By using survival time as the only outcome measure (Kaplan-Meier method and Cox regression), the performance of any prognostic system was assessed according the criteria of discriminatory and stratification abilities between different stages, homogeneity of survival within each stage and additional explanatory power respect to the other classifications. RESULTS: In the particular cohort studied, BCLC proved the best HCC prognostic system. This was true for the whole study group and for the 2 subgroups of surgical and non-surgical patients. CONCLUSIONS: BCLC staging showed the best interpretation of the survival distribution in an HCC population comprising a large proportion of tumors treated with potentially radical therapies.  相似文献   
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