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We analysed a group of 390 patients, diagnosed with chronic lymphocytic leukaemia (CLL). Cases were subclassified as morphologically typical and atypical CLL according to the criteria of the FAB proposal. Typical CLL cases were mostly diagnosed at a low-risk stage (Binet A/Rai 0), required no immediate treatment and expected a long survival; atypical CLL cases mostly presented at a more advanced risk stage (Binet B/Rai I–II), usually required immediate treatment and their survival was shorter. Moreover, clinical staging was of prognostic significance in typical but not in atypical cases.   In typical CLL, del(11q) was the most common chromosomal abnormality (21%) whereas in atypical CLL trisomy 12 was found in about 65% of the cases documented with an abnormal karyotype. Although chromosomal abnormalities were associated with a poor survival in typical CLL, they are of no prognostic significance in atypical CLL.   Based on these data, we conclude that subtyping CLL by morphology enables the identification of two groups of cases, each characterized by a specific clinical presentation, different cytogenetic abnormalities and prognostic parameters. We speculate that these two groups may represent two related, but different, diseases with different prognostic parameters and a different survival.  相似文献   
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In a single outbreak on the East coast of Madagascar, more than 500 people, 98 of whom died, were poisoned by the flesh of a shark, Carcharhinus amboinensis. From clinical symptoms it can be concluded that this poisoning is due to ciguatera toxins. It is the first case of a severe outbreak caused by a shark, and it is the first case with a mortality rate of 20%.  相似文献   
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BACKGROUND: After hematopoietic cell transplantation (HCT), hepatitis due to hepatitis B virus (HBV) rarely occurred beyond the initial 12 months after transplantation. OBJECTIVES: We investigated the cause of "late" hepatitis due to HBV infection in two recipients after allogeneic HCT. STUDY DESIGN: Two male patients with acute myeloid leukemia and light chain myeloma, respectively, developed HBV-related hepatitis more than 2 years after HCT. All serum samples collected from the recipients, donors and their respective spouses were tested for HBV DNA by nested PCR, and if positive further quantified by Digene Hybrid Capture assay II. The HBV genotype was determined by PCR and sequencing. RESULTS: Genotypic analysis suggested that the cause of "late" hepatitis was due to acute HBV infection transmitted from their respective spouse. CONCLUSION: Our findings suggested that sexual precautions should be taken in these patients after HCT. Alternatively, or even additionally, active vaccination should be delivered to these patients once they have lost their HBV immunity.  相似文献   
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Macro and micronutrient deficiencies pose serious health challenges globally, with the largest impact in developing regions such as subSaharan Africa (SSA), Latin America and South Asia. Maize is a good source of calories but contains low concentrations of essential nutrients. Major limiting nutrients in maize-based diets are essential amino acids such as lysine and tryptophan, and micronutrients such as vitamin A, zinc (Zn) and iron (Fe). Responding to these challenges, separate maize biofortification programs have been designed worldwide, resulting in several cultivars with high levels of provitamin A, lysine, tryptophan, Zn and Fe being commercialized. This strategy of developing single-nutrient biofortified cultivars does not address the nutrient deficiency challenges in SSA in an integrated manner. Hence, development of maize with multinutritional attributes can be a sustainable and cost-effective strategy for addressing the problem of nutrient deficiencies in SSA. This review provides a synopsis of the health challenges associated with Zn, provitamin A and tryptophan deficiencies and link these to vulnerable societies; a synthesis of past and present intervention measures for addressing nutrient deficiencies in SSA; and a discussion on the possibility of developing maize with multinutritional quality attributes, but also with adaptation to stress conditions in SSA.  相似文献   
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Essential learning tools for continuing medical education are a challenge in today’s rapidly evolving field of reproductive medicine. The Midwest Reproductive Symposium International (MRSi) is a yearly conference held in Chicago, IL. The conference is targeted toward physicians, geneticists, nurses, allied health professionals, mental health professionals, business administration professionals, and reproductive endocrinology and infertility (REI) fellows engaged in the practice of reproductive medicine. In addition to the scientific conference agenda, there are specific sessions for nurses, mental health professionals, and REI fellows. Unique to the MRSi conference, there is also a separate “Business Minds” session to provide education on business acumen as it is an important element to running a department, division, or private clinic.  相似文献   
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Advances in hepatitis C: What is coming in the next 5 years?   总被引:3,自引:0,他引:3  
Hepatitis C virus (HCV) is a leading cause of chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. Numerous advances have been made in the understanding of HCV replication, including detailed molecular characterization of its viral proteins and genomic RNA. The inability to grow HCV in cell culture had impeded the development of antiviral agents against this virus. To overcome this obstacle, a number of unique tools have been prepared, such as molecular clones that are infectious in the chimpanzee animal model of infection, and the development of a subgenomic replicon system in Huh7 cells. In addition, the major non-structural proteins have been crystallized, thus enabling rational drug design directed to these targets. Current developments in antiviral agents are reviewed in the context of these potential new viral targets for the future treatment of HCV in chronically infected individuals.  相似文献   
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In the Indian state of Bihar, the sensitivities and specificities of direct agglutination tests (DAT) and rK39 test strips for the detection of Leishmania donovani infection in humans were explored and found to be generally good (92%-100%). When 172 asymptomatic individuals [16 'case-contacts' who lived in the same households as past or current, confirmed cases of visceral leishmaniasis (VL) and 156 other subjects from neighbouring households] were tested, the same 36 (21%) individuals, including all 16 'case-contacts', were found seropositive using each type of test. When followed-up after 3 months, 18 of the individuals who had been found seropositive in the baseline survey remained seropositive, and eight (44%) of these had developed symptomatic VL, with amastigotes in their splenic aspirates. Seven (44%) of the 16 'case-contacts' but only one (5%) of the other 20 subjects found seropositive at baseline went on to develop VL within 3 months. Although the strip test appeared slightly better than DAT for predicting the development of VL in the 172 subjects, either type of test may be very useful for the early detection of asymptomatic L. donovani infection and thus the identification of those at relatively high risk of developing VL.  相似文献   
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