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941.
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944.
The role of the peripheral blood (PB) CD34(+) cell count in predicting the CD34(+) cell yield in hematopoietic progenitor cell apheresis collections is well established. However, sometimes unexpectedly poor CD34(+) cell yields are obtained. To determine the effect, if any, of a range of factors on the ability of the PB CD34(+) count to predict collection CD34(+) cell count, we performed a retrospective analysis on consecutive hematopoietic progenitor cell apheresis collections between 2004 and 2008. Factors investigated included mobilization regimen, PB white blood cell count, body weight, and disease. After exclusion of collections involving apheresis complications, a total of 1,225 PB CD34(+) cell results with corresponding collection CD34(+) cell results from 458 patients were analyzed. Although differences in the median PB CD34(+) cell counts and collection CD34(+) cell counts were seen between mobilized collections with chemotherapy plus granulocyte colony-stimulating factor and those with granulocyte colony-stimulating factor alone, the predictive capability of the PB CD34(+) cell count for the collection CD34(+) cell yield remained similar. Although poorer collection efficiencies were observed in the myelodysplastic syndrome/myeloproliferative disorder diagnostic subgroup, our findings confirm that PB CD34(+) cell analysis remains a powerful and irreplaceable tool for predicting hematopoietic progenitor cell apheresis CD34(+) cell yield.  相似文献   
945.

Objective

A new vaccine, Multimeric-001, containing conserved linear epitopes from the HA, NP, and M1 proteins of influenza type A and type B strains was designed to protect against seasonal and pandemic influenza virus strains, regardless of mutations. We assessed its safety and tolerability and characterized humoral and cellular immune responses elicited by its administration.

Methods

Sixty healthy volunteers received either 250 or 500 μg injections, with or without adjuvant (Montanide ISA 51VG), or matching placebo. Two intramuscular injections were administered, 21 days apart.

Results

Treatment was well tolerated and no significant adverse events were noted. Forty-two days after first injection, there was a 50-fold and 37-fold increase in IgG titers against Multimeric-001 protein, following the adjuvanted 500 and 250 μg doses, respectively. Sera from immunized subjects lysed MDCK cells infected with strains of influenza representing the major strains that infect humans: H1N1, H3N2, and influenza B. Proliferation of peripheral blood mononuclear cells as well as increase in IL-2 and IFN-gamma secretion occurred following incubation with the vaccine.

Conclusion

This vaccine model differs fundamentally from the current influenza virus vaccines, as it does not contain the variable regions of the virus hemagglutinin and hence does not induce hemagglutination inhibition antibodies that serve as surrogate markers for protection. In order to demonstrate the potential efficacy of the Multimeric-001, an alternative assay was employed, in which the lysis of MDCK cells infected with different virus strains was shown, with the involvement of the complement mechanism. The humoral and cellular responses suggest a cross-immunity of the vaccine toward influenza virus strains regardless of mutations. These results corroborate the protective effect of the vaccine, previously shown in animals. Larger-scale studies are under way to further substantiate the safety and efficacy of the vaccine candidate.  相似文献   
946.
Adolescence is a developmental period characterized by elevated stress, heightened risky behaviors, and increases in psychopathology. Emotion dysregulation is a hypothesized contributor to negative outcomes and to the onset of psychopathology during adolescence. However, the dysregulation of negative emotion has been the focus of research while the literature on positive emotion in adolescent psychopathology is limited. This review highlights both the development of normative and dysregulated positive emotion during adolescence. First, the literature on normative adolescent emotional development and on negative emotional regulation is briefly reviewed, followed by a discussion of current theories of positive emotion, which are grounded in the adult literature. From a developmental perspective, the dimension of approach motivation within positive emotion is emphasized throughout and frames the review. This conceptualization guides organization of literatures on normative experiences of positive emotion in adolescence and the role of dysregulated positive emotion in adolescent psychopathology, specifically adolescent depression, anxiety, bipolar disorder, externalizing disorders and eating disorders. Last, future directions in the study of adolescent positive emotion and its regulation and the implications of highlighting approach motivation in normative and dysregulated positive emotion in adolescence are detailed.  相似文献   
947.
948.
949.
Astrocytomas represent the largest and most common subgroup of brain tumors. Anaplastic astrocytoma (WHO grade III) may arise from low-grade diffuse astrocytoma (WHO grade II) or as primary tumors without any precursor lesion. Comprehensive analyses of anaplastic astrocytomas combining both cytogenetic and molecular cytogenetic techniques are rare. Therefore, we analyzed genomic alterations of five anaplastic astrocytomas using high-density single nucleotide polymorphism arrays combined with GTG-banding and FISH-techniques. By cytogenetics, we found 169 structural chromosomal aberrations most frequently involving chromosomes 1, 2, 3, 4, 10, and 12, including two not previously described alterations, a nonreciprocal translocation t(3;11)(p12;q13), and one interstitial chromosomal deletion del(2)(q21q31). Additionally, we detected previously not documented loss of heterozygosity (LOH) without copy number changes in 4/5 anaplastic astrocytomas on chromosome regions 5q11.2, 5q22.1, 6q21, 7q21.11, 7q31.33, 8q11.22, 14q21.1, 17q21.31, and 17q22, suggesting segmental uniparental disomy (UPD), applying high-density single nucleotide polymorphism arrays. UPDs are currently considered to play an important role in the initiation and progression of different malignancies. The significance of previously not described genetic alterations in anaplastic astrocytomas presented here needs to be confirmed in a larger series.  相似文献   
950.

Objective

To describe a theoretical framework for assessing knowledge about the possible outcomes of participating in bowel cancer screening for the faecal occult blood test.

Methods

The content of the knowledge measure was based on the UK General Medical Council's screening guidelines and a theory-based approach to assessing gist knowledge (Fuzzy Trace Theory). It comprised conceptual and numeric questions to assess knowledge of the underlying construct (e.g. false positive concept) and the approximate numbers affected (e.g. likelihood of a false positive). The measure was used in a randomised controlled trial involving 530 adults with low education, to compare the impact of a bowel screening decision aid with a screening information booklet developed for the Australian Government National Bowel Cancer Screening Program.

Results

The numeric knowledge scale was particularly responsive to the effects of the decision aid; at follow-up decision aid participants’ numeric knowledge was significantly greater than the controls (P < 0.001). This contrasts with the conceptual knowledge scale which improved significantly in both groups from baseline to follow-up (P < 0.001).

Conclusion

Our theory-based knowledge measure was responsive to change in conceptual knowledge and to the effect on numeric knowledge of a decision aid.

Practice implications

This theoretical framework has the potential to guide the development of knowledge measures in other screening settings.  相似文献   
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