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31.
This study chronicles an at-risk mother's experience in an alternative foster care program. Influenced by attachment theory, the Children's Ark reunited children with their mothers in a supervised home environment while also providing residential support, intensive therapy, and education. After losing custody of her infant Kindra, 18-year-old Anna participated in the Ark for 2 years, after which she regained custody of Kindra. We assessed Anna and Kindra at multiple times using a variety of instruments, including a semi-structured interview, the Adult Attachment Interview, and the Strange Situation procedure. Anna moved from a profoundly insecure state of mind to a secure one, while Kindra moved from a resistant to a secure attachment. Qualitative analyses of Anna's interviews documented growth in her capacity to use the important relationships at the Ark as secure bases and to welcome rather than fear intimacy with Kindra. The qualitative analyses also described growth in Anna's capacities for reflective functioning and positive changes in her internal working model. We conclude with an analysis of the process of change from the perspective of attachment theory. 相似文献
32.
33.
Mahmutefendić H Kucić N Lucin P 《American journal of reproductive immunology (New York, N.Y. : 1989)》2002,48(2):87-95
PROBLEM: To characterize the constitutive internalization of major histocompatibility complex (MHC) class I molecules, we have studied the expression of completely conformed (full) and unconformed (empty) L(d) molecules on non-polarized murine P815 cells. METHODS OF STUDY: Spontaneous endocytosis of L(d) molecules was induced by cycloheximide, an inhibitor of protein synthesis, and their disappearance from the cell surface was determined by flow cytometry. In order to investigate the mechanism of internalization, a palette of inhibitors of endocytosis and vesicular transport was used. RESULTS: Inhibitors of clathrine endocytosis did not influence the internalization of L(d) molecules. Inhibitors of caveolar endocytosis and inhibitors of endolysosomal degradation prevented down-regulation of empty, but not of full L(d) molecules. CONCLUSIONS: Empty L(d) molecules are internalized mostly by caveolar endocytosis and full L(d) molecules use a different pathway, neither clathrine-mediated nor caveolar. After internalization, full L(d) molecules are probably degraded and empty L(d) molecules recycle between endosomal compartment and the cell surface before they enter into the degradation compartment. 相似文献
34.
35.
F. Fernández-Cuenca L. Martínez-Martínez A. Pascual M. De Cueto O. Gutiérrez J. Nieto E. J. Perea 《Clinical microbiology and infection》2003,9(5):449-452
The aim of this study was to evaluate the WIDER I system for susceptibility testing of Haemophilus influenzae and Streptococcus pneumoniae . MICs of 12 antimicrobials against 42 H. influenzae and 58 S. pneumoniae strains were determined using 1W MIC panels and compared with those obtained by microdilution. Overall essential agreements were >99%. Very major errors were not detected. Major errors occurred with ampicillin (1.7% H. influenzae ). Minor errors were 2.3% (amoxicillin–clavulanate, cefuroxime, chloramphenicol), 7.1% (ampicillin) and 16.7% (clarithromycin) for H. influenzae , and 1.7% (chloramphenicol, erythromycin, meropenem), 3.4% (amoxicillin–clavulanate, cefuroxime, tetracycline) and 8.6% (levofloxacin) for S. pneumoniae . The WIDER I system is a reliable method for susceptibility testing of H. influenzae and S. pneumoniae . 相似文献
36.
J. Vinasco Y. Beraun A. Nieto A. Fralle E. Pareja L. Mataran J. Martin 《Tissue antigens》1997,50(1):71-73
A role for heat shock proteins (hsp) in rheumatoid arthritis has been suggested. In addition, the specific binding of human HSP70 protein to QKRAA and RRRAA motifs within the HV3 region of disease-associated DRB1*0401 and DRB1*1001 molecules, respectively, has been proposed as being relevant to rheumatoid arthritis. The purpose of this work was to analyze the influence of HSP70 gene polymorphism on the susceptibility to or severity of rheumatoid arthritis and to investigate the possible contribution of these HSP70 polymorphisms in determining HLA-DRB1*0401/*1001 disease association. The frequencies of the HSP70-1, HSP70-2 and HSP70-hom genotypes were analyzed by PCR-RFLP using BsrBI , Pst I and Nco I enzymes, respectively, in patients with heumatoid arthritis and in healthy controls. No significant differences were observed when HSP70 alleled istribution between the groups under study were compared. Moreover, we did not observe any significant difference in HSP70 allele frequencies between patients positive for HLA-DRB1*0401/*1001 alleles and matched controls. Our data indicate that HSP70 gene polymorphisms do not appear to be relevant in the susceptibility to or severity of rheumatoid arthritis. 相似文献
37.
Craig S. Henriquez Natalia Trayanova Robert Plonsey 《Annals of biomedical engineering》1990,18(4):367-376
A fully three-dimensional model of the ventricular or atrial free wall will involve a planar geometry of finite thickness.
The governing equations for the interstitial and extracellular potential of a planar slab of cardiac tissue comprised of parallel
fibers undergoing uniform plane-wave activation are presented. A comparison with a bidomain of cylindrical geometry with the
same half-thickness shows that the potentials in the planar bidomain (as a function of depth) approach core-conductor behavior
more quickly. 相似文献
38.
Summary The phenotypic trait starry colony in Saccharomyces is associated with a high spontaneous rho
–
petite mutability. Genetic analysis of this trait has shown the high rho
– mutability to be caused by several modifying genes present together in the strains studied. Every single modifying gene produces only a relatively small enhancement of the rho
– mutability. 相似文献
39.
Yago Nieto Nigel Patton Timothy Hawkins Ruth Spearing Scott I Bearman Roy B Jones Elizabeth J Shpall Rachel Rabinovitch Chan Zeng Anna Barón Peter A McSweeney 《Biology of blood and marrow transplantation》2006,12(2):217-225
We evaluated tacrolimus/mycophenolate mofetil (MMF) for graft-versus-host disease (GVHD) prophylaxis after a nonmyeloablative stem cell transplantation (NST) from a matched sibling donor (MSD). Thirty-two patients (median age, 57 years) with advanced hematologic malignancies, who were poor candidates for a conventional myeloablative transplantation, received fludarabine (30 mg/m(2), day -4 to day -2), total-body irradiation (TBI) (200 cGy, day 0), infusion of donor peripheral blood progenitor cells (day 0), oral tacrolimus 0.06 mg/kg twice daily (from day 3), and oral MMF at 15 mg/kg twice daily (days 0-+27). Tacrolimus was tapered from day +100 to day +180 in those patients with indolent malignancies (n = 25), and from day +35 to day +56 in those with aggressive tumors (n = 7). Regimen toxicities and myelosuppression were mild, allowing 75% of patients to have entirely outpatient transplantations. One patient (3%) experienced a nonfatal graft rejection. Rates of grades II-IV and III-IV acute GVHD were 15.6% and 3%, respectively. Acute GVHD was diagnosed at median day +78 (range, days +31-+84). Extensive chronic GVHD was observed in 10 of 24 evaluable patients (41.6%) at a median onset of day +198 (range, days +128-+277), either spontaneously (n = 5) or elicited after tumor progression (n = 5). Five patients experienced transplantation-related mortality (TRM) (15.6%) from either acute GVHD-related multiorgan failure (MOF) (n = 3) or infectious complications (n = 2). At median follow-up of 19 months (range, 2-41 months), the overall survival, progression-free survival, and disease-free survival rates are 62.5%, 50%, and 40%, respectively. In conclusion, the use of tacrolimus/MMF after MSD NST is associated with encouraging rates of GVHD control. 相似文献
40.
Isaguliants MG Petrakova NV Mokhonov VV Pokrovskaya K Suzdaltzeva YG Krivonos AV Zaberezhny AD Garaev MM Smirnov VD Nordenfelt E 《Immunology letters》2003,88(1):1-13
Nonstructural protein 3 (NS3) of human hepatitis C virus (HCV) is a conserved multi-functional protein essential for replication and translation of viral RNA and polyprotein processing. Early T-cell response against NS3 is capable of restricting viremia. We aimed at characterizing the immunogenicity in gene immunization of the conserved regions of NS3 critical for protein folding and activity. C57BL/6 mice were injected with NS3 gene of Russian HCV 1b isolate 274933RU. Immunization did not exert any overt histological changes and had no long-term effects on the immune status of NS3 gene-recipients. The immune response in NS3 gene-recipients was screened by antibody ELISA, T-cell proliferation test and immune assays for specific cytokine production. T-lymphocytes of NS3 gene-recipients proliferated in response to peptides representing conserved regions of protease and ATPase/helicase. Stimulated T-lymphocytes produced IL-2, and in response to protease-derived peptides, also IFN-gamma. Potent and long-lasting antibody response was raised against conserved NS3 regions including "Greek-key" motif of protease, motifs II, V and polynucleotide-binding domains of ATPase/helicase. Thus, gene immunization effectively targeted conserved regions critical for NS3 protease and helicase function. In type and specificity, immune response of NS3 gene-immunized mice mimicked immunity achieved in the acute self-limiting HCV infection of human and primates and in virus-exposed healthy individuals, indicating promiscuity of NS3 as immunogen. 相似文献