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71.
The aim of the study was to define the minimal effective dose (MED) of granulocyte colony-stimulating factor (G-CSF) among five daily doses following chemotherapy for peripheral blood stem cell (PBSC) collection. Twenty-five patients were included in this double-blind dose-finding phase II study conducted according to a two-stage Bayesian design. The estimated probabilities of success for PBSC collection for the G-CSF doses of 50, 75, 100, 125 and 150 microg/m2/day were 84%, 87.7%, 91%, 93.9 and 96.4%, respectively. Low G-CSF doses may be used with a similar probability of success as conventional doses and could allow significant savings.  相似文献   
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73.
The pattern recognition molecules Nod1 and Nod2 play important roles in intestinal homeostasis; however, how these proteins impact on the development of inflammation during bacterial colitis has not been examined. In the streptomycin-treated mouse model of Salmonella colitis, we found that mice deficient for both Nod1 and Nod2 had attenuated inflammatory pathology, reduced levels of inflammatory cytokines, and increased colonization of the mucosal tissue. Nod1 and Nod2 from both hematopoietic and nonhematopoietic sources contributed to the pathology, and all phenotypes were recapitulated in mice deficient for the signaling adaptor protein Rip2. However, the influence of Rip2 was strictly dependent on infection conditions that favored expression of the Salmonella pathogenicity island 2 (SPI-2) type III secretion system (TTSS), as Rip2 was dispensable for inflammation when mice were infected with bacteria grown under conditions that promoted expression of the SPI-1 TTSS. Thus, Nod1 and Nod2 can modulate inflammation and mediate efficient clearance of bacteria from the mucosal tissue during Salmonella colitis, but their role is dependent on the expression of the SPI-2 TTSS.  相似文献   
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75.
We previously described an autosomal-recessive mutation named nackt (nkt) exhibiting partial alopecia associated with CD4(+) T-cell deficiency. Also, we recently reported that nkt (now Ctsl(nkt)) comprises a deletion in the cathepsin L (Ctsl) gene. Another recent study reported that Ctsl knockout mice have CD4(+) T-cell deficiency and periodic shedding of hair, which recapitulate the nkt mutation and the old furless (fs) mutation. The current study focuses on the dermatological aspects of the nkt mutation. Careful histological analysis of skin development of homozygous nkt mice revealed a delayed hair follicle morphogenesis and late onset of the first catagen stage. The skin of Ctsl(nkt)/Ctsl(nkt) mice showed mild epidermal hyperplasia and hyperkeratosis, severe hyperplasia of the sebaceous glands, and structural alterations of hair follicles. Epidermal differentiation seems to be affected in nkt skin, with overexpression of involucrin and profilaggrin/filaggrin along with focal areas of keratin 6 expression in the interfollicular epidermis. Severe epidermal hyperplasia, acanthosis, orthokeratosis, and hyperkeratosis were only observed in mice maintained in nonpathogen-free environments. The analysis of Rag2-/- Ctsl(nkt)/Ctsl(nkt) double-mutant mice indicates that the skin defect remains under the absence of T and B cells. This animal model provides in vivo evidence that cysteine protease cathepsin L plays a critical role in hair follicle morphogenesis and cycling, as well as epidermal differentiation.  相似文献   
76.
Fast FFT-based bioheat transfer equation computation   总被引:1,自引:0,他引:1  
This paper describes a modeling method of the tissue temperature evolution over time in hyper or hypothermia. The tissue temperature evolution over time is classically described by Pennes’ bioheat transfer equation which is generally solved by a finite difference method. In this paper we will present a method where the bioheat transfer equation can be algebraically solved after a Fourier transformation over the space coordinates. As an example, we implemented this method for the simulation of a percutaneous high intensity ultrasound hepatocellular carcinoma curative treatment and compared it with the finite difference method and experimental data.  相似文献   
77.
Follicular dendritic cell tumor (FDCT) is a rare tumor mainly located in laterocervical lymph nodes. We report one case of mediastinal FDCT associated with a history of bullous skin disease and clinically obvious immunosuppression. This tumor was characterized by heavy mast cell infiltration. Mast cells were in close relationship with tumor cells as demonstrated by ultrastructural examination and their presence are probably related with the strong expression of mast cell chemoattractants as fraktalkine and stromal cell-derived factor-1α by tumor cells. The long follow-up period of more than 17 years allowed to us assess the relatively indolent evolution of this tumor characterized by three slowly growing local recurrences without metastasis.  相似文献   
78.
Despite an increase in plasma IL-7 levels, the CD4 T-cell pool decrease progressively in HIV-infected patients. Here we report on our tests to check the hypothesis that defects in the IL-7 receptor system might be involved in this phenomenon. The cell surface expression of CD127 was measured ex vivo in CD4 and CD8 T lymphocytes drawn from 3 groups of HIV patients. IL-7 function was also followed in vitro by measuring IL-7-driven T-cell proliferation, the induction of the CD25 activation marker, and overexpression of the antiapoptotic molecule Bcl-2. Untreated viremic patients showed a slight but significant decrease in CD127 expression on the surface of their CD4 lymphocytes. By contrast, CD127 expression was substantially altered on the surface of CD8 T lymphocytes taken from untreated viremic patients. IL-7-induced overexpression of the antiapoptotic molecule Bcl-2 was dramatically altered in viremic patients, whereas IL-7-dependent CD25 induction and T-cell proliferation were reduced. Highly active antiretroviral therapy partially corrected these defects in patients with an undetectable viral load and CD4 counts of more than 400 cells/microL. The effects of HAART were less pronounced in patients with undetectable VL but low CD4 counts (<250 cells/microL). The IL-7 receptor is dysfunctional in the CD4 and CD8 lymphocytes of HIV-infected patients. This may be due to abnormal activation of the immune system in HIV-infected patients and may contribute to the reduced CD4 count and the altered function of the CD8 compartment.  相似文献   
79.
The articles in this special issue of Developmental Psychobiology were presented in May 2005 at an international institute on developmental science hosted by the University of North Carolina at Chapel Hill. Conducted annually at one of the participating universities, these meetings are intended to foster collaboration and build consensus on specific theoretical, methodological, and analytical issues faced by developmentally oriented researchers. The overall goal of the 2005 meeting, titled "Integrating Biology and Developmental Science," was to identify different ways by which a developmental study of psychological phenomena in their joint biological and behavioral aspects may shed new light on their organization in the individual. The six contributions to this special issue illustrate how a biological window on developmental processes can further this scientific endeavor.  相似文献   
80.
We report the case of a cystic fibrosis patient colonized with a smooth-morphotype form of Mycobacterium abscessus who developed acute respiratory failure with the emergence of an isogenic rough (R) variant while he was recovering from peritonitis-induced shock. This report emphasizes the role of R forms in severe M. abscessus infections.  相似文献   
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