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121.
Comparative genomic hybridization pattern distinguishes T-cell/histiocyte-rich B-cell lymphoma from nodular lymphocyte predominance Hodgkin's lymphoma 总被引:3,自引:0,他引:3 下载免费PDF全文
Franke S Wlodarska I Maes B Vandenberghe P Achten R Hagemeijer A De Wolf-Peeters C 《The American journal of pathology》2002,161(5):1861-1867
Several lines of evidences suggest that T cell/histiocyte-rich B-cell lymphoma (T/HRBCL) represents an aggressive variant of the clinically indolent entity nodular lymphocyte predominance Hodgkin's lymphoma (LPHL). Still, this view has not yet been supported by firm genetic evidence. In this study, we analyzed 17 T/HRBCL cases using comparative genomic hybridization (CGH) combined with microdissection of single CD20+ neoplastic cells and DNA amplification by degenerate oligonucleotide primed-polymerase chain reaction, an approach we previously used in LPHL. Genomic imbalances were detected in all cases (in total, 80 changes). The most common imbalances included gain of Xq, 4q13q28, Xp21p11, and 18q21, and loss of 17p. Of note, a partial gain of 4q, a rare change in lymphoma, is also among the genomic imbalances most frequently encountered in LPHL. On the other hand, the CGH profiles of T/HRBCL and LPHL showed several distinct features, in particular with respect to the number of genomic imbalances (average of 4.7 in T/HRBCL versus 10.8 in LPHL) and their distribution (usually 1 to 5 in T/HRBCL versus 6 to 22 in LPHL). Altogether, our CGH findings of shared as well as distinctive cytogenetic features in both diseases suggest that T/HRBCL constitutes a separate lymphoma entity, possibly originating from the same precursor cell as LPHL. 相似文献
122.
Rorden C Driver J 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2001,137(3-4):487-496
Research on visual attention has demonstrated that covert attention can be focused on particular locations within one hemifield,
but that a specific "meridian" cost may also be found for shifting attention between hemifields. These issues have received
less consideration for audition, even though reliable behavioral measures for the effects of spatial attention on hearing
are now available. We examined the spatial distribution of covert attention in an auditory task following spatially non-predictive
peripheral auditory cues (which should induce exogenous attention shifts), or following symbolic central cues that predicted
the likely location for the auditory target (to induce endogenous attention shifts). In both cases, we found that attention
can be focused not only on one hemifield versus another, but also within one hemifield in an auditory task. However, there
was no unequivocal evidence for a meridian effect in audition.
Electronic Publication 相似文献
123.
124.
Type 1 immunity provides both optimal mucosal and systemic protection against a mucosally invasive, intracellular pathogen 总被引:2,自引:0,他引:2 下载免费PDF全文
It has been hypothesized that optimal vaccine immunity against mucosally invasive, intracellular pathogens may require the induction of different types of immune responses in mucosal and systemic lymphoid tissues. Mucosal type 2/3 responses (producing interleukin-4 [IL-4], IL-6 and/or transforming growth factor beta) could be necessary for optimal induction of protective secretory immunoglobulin A responses. On the other hand, systemic type 1 responses (including gamma interferon [IFN-gamma], tumor necrosis factor alpha, and optimal cytotoxic T-cell responses) are likely to be critical for protection against the disseminated intracellular replication that occurs after mucosal invasion. Despite these predictions, we recently found that vaccines inducing highly polarized type 1 immunity in both mucosal and systemic tissues provided optimal mucosal and systemic protection against the protozoan pathogen Trypanosoma cruzi. To further address this important question in a second model system, we now have studied the capacity of knockout mice to develop protective immune memory. T. cruzi infection followed by nifurtimox treatment rescue was used to immunize CD4, CD8, beta2-microglobulin, inducible nitric oxide synthase (iNOS), IL-12, IFN-gamma, and IL-4 knockout mice. Despite the previously demonstrated importance of CD4(+) T cells, CD8(+) T cells, and nitric oxide for T. cruzi immunity, CD4, CD8, and iNOS knockout mice developed mucosal and systemic protective immunity. However, IL-12, IFN-gamma, and beta2-microglobulin-deficient mice failed to develop mucosal or systemic protection. In contrast, IL-4 knockout mice developed maximal levels of both mucosal and systemic immune protection. These results strongly confirm our earlier conclusion from studies with polarizing vaccination protocols that type 1 immunity provides optimal mucosal and systemic protection against a mucosally invasive, intracellular pathogen. 相似文献
125.
126.
This study examines interpopulation variations in the facial skeleton of 10 modern human populations and places these in an ontogenetic perspective. It aims to establish the extent to which the distinctive features of adult representatives of these populations are present in the early post natal period and to what extent population differences in ontogenetic scaling and allometric trajectories contribute to distinct facial forms. The analyses utilize configurations of facial landmarks and are carried out using geometric morphometric methods. The results of this study show that modern human populations can be distinguished based on facial shape alone, irrespective of age or sex, indicating the early presence of differences. Additionally, some populations have statistically distinct facial ontogenetic trajectories that lead to the development of further differences later in ontogeny. We conclude that population-specific facial morphologies develop principally through distinctions in facial shape probably already present at birth and further accentuated and modified to variable degrees during growth. These findings raise interesting questions regarding the plasticity of facial growth patterns in modern humans. Further, they have important implications in relation to the study of growth in the face of fossil hominins and in relation to the possibility of developing effective discriminant functions for the identification of population affinities of immature facial skeletal material. Such tools would be of value in archaeological, forensic and anthropological applications. The findings of this study underline the need to examine more deeply, and in more detail, the ontogenetic basis of other causes of craniometric variation, such as sexual dimorphism and hominin species differentiation. 相似文献
127.
Combination of PCR targeting the VD2 of omp1 and reverse line blot analysis for typing of urogenital Chlamydia trachomatis serovars in cervical scrape specimens 总被引:3,自引:0,他引:3 下载免费PDF全文
Molano M Meijer CJ Morré SA Pol R van den Brule AJ 《Journal of clinical microbiology》2004,42(7):2935-2939
In this study we developed and evaluated a new PCR-based typing assay, directed to the VD2 region of the omp1 gene, for the detection and typing of urogenital Chlamydia trachomatis infections. A nested VD2 PCR-reverse line blot (RLB) assay was developed for the typing of nine different urogenital serovars of C. trachomatis. The assay developed was tested with reference strains of C. trachomatis serovars and cervical scrapes of 86 Colombian women previously found to be positive for C. trachomatis by using plasmid PCR. Two sets of primers directed to the VD2 region of the omp1 gene of C. trachomatis were designed, and fragments of 220 and 166 bp were generated in the primary and nested PCRs, respectively. In addition, an RLB assay was developed to identify nine different urogenital serovars of C. trachomatis (Ba, D, E, F, G, H, I, J, and K) and group controls, including group B (Ba, D, and E), group C (I, J, K, and H), and an intermediate group (F and G). Using this assay, we were able to type 81 of the 86 samples (94.2%). Of these samples, 91.3% were single C. trachomatis infections, and 8.7% were multiple infections. The most common serovars identified were serovars D (22.2%), F (18.5%), G (13.6%), and E (12.3%). Of the women with multiple C. trachomatis infections, >50% contained both serovars D and E. The nested VD2 PCR-RLB developed is a simple, fast, and specific method for the identification of individual urogenital C. trachomatis serovars previously detected by using plasmid PCR. Moreover, it is an appropriate method for studying multiple C. trachomatis infections and for use in large epidemiological studies. 相似文献
128.
Claire Mayers Gerard Leavey Christina Vallianatou Chris Barker 《Clinical psychology & psychotherapy》2007,14(4):317-327
This qualitative study explored the process of help‐seeking and therapy among clients with religious or spiritual beliefs. Ten clients who were currently in, or had recently finished, therapy were interviewed. Participants reported using their religious or spiritual beliefs to cope with their psychological problems before and during therapy. Prior to therapy, they were worried that secular‐based help might weaken their faith. However, the experience of having psychological distress and the process of receiving therapy were both perceived as strengthening to faith and ultimately part of a spiritual journey. Contrary to expectations, a match between the spirituality or religious affiliation of the therapist and client was not considered important. This implies that the ‘religiosity gap’ between secular therapists and clients with religious/spiritual beliefs is bridgeable. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
129.
Carolyn A Chew-Graham Karina Lovell Chris Roberts Robert Baldwin Michael Morley Alistair Burns David Richards Heather Burroughs 《The British journal of general practice》2007,57(538):364-370
BACKGROUND: Depression is the most common mental health disorder in people aged over 65 years. Late-life depression is associated with chronic illness and disability. AIM: To investigate the feasibility of a collaborative care model for depression in older people in a primary care setting. DESIGN OF STUDY: Randomised controlled trial with 16-weeks follow up. SETTING: A primary care trust in Manchester. METHOD: Participants were 105 people aged 60 years or older who scored 5 or more on the Geriatric Depression Scale; 53 were randomly allocated to an intervention group and 52 to a usual care group. The intervention group received care managed by a community psychiatric nurse who delivered an intervention comprising a facilitated self-help programme with close liaison with primary care professionals and old-age psychiatry according to a defined protocol. The usual care group received usual GP care. A nested qualitative study explored the views of the health professionals and patients regarding the acceptability and effectiveness of the intervention. RESULTS: The main outcome measure was recovery from depression. Patients in the intervention group were less likely to suffer from major depressive disorder at follow up compared with usual care (0.32, 95% confidence = interval = 0.11 to 0.93, P = 0.036). The qualitative component of the study demonstrated the acceptability of the intervention to patients. CONCLUSION: A model of collaborative care for older people with depression, used in a primary care setting with a facilitated self-help intervention is more effective than usual GP care. This study demonstrates that the implementation of a collaborative care model is feasible in UK primary care and that the intervention is effective and acceptable to patients. 相似文献
130.
TNF revisited: TNF-independent antitumor activity in sera of mice sensitized with Propionibacterium acnes and challenged with lipopolysaccharide 总被引:1,自引:0,他引:1
Schwamberger G Hammerl P Ferber E Freudenberg M Galanos C 《Journal of leukocyte biology》2003,74(6):1056-1063
Sera of mice sensitized with bacteria and subsequently challenged with lipopolysaccharide promote hemorrhagic necrosis of tumors in vivo and display cytotoxic activity against tumor cells in vitro, which has been attributed to the induction of tumor necrosis factor (TNF). Here, we describe the induction of a previously unrecognized antitumor activity in such sera, which is distinct from TNF but displays tumor-specific cytocidal activity in vitro as well as potent tumor-regressing activity in vivo. Biochemical analysis of this activity yielded a molecular mass of approximately 150 kDa, closely resembling a novel tumoricidal factor of murine macrophages (Mphi) termed MTC 170 (Mphi tumor cytotoxin, approximate molecular mass 170 kDa), which we have previously proposed to constitute a major effector pathway for the destruction of tumor cells by activated Mphi. 相似文献