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991.
Paul K. Hildebrandt James D. Conroy Adam E. McKee M. B. A. Nyindo David L. Huxsoll 《Infection and immunity》1973,7(2):265-271
The ultrastructure of Ehrlichia canis was examined in both pulmonary mononuclear cells and in monocytes cultured from an infected dog. The cytoplasmic inclusions, or morulae, of E. canis consisted of a membrane-lined vacuole-containing elementary bodies which varied in size and number. The elementary bodies were bound by two trilamellar membranes. The organism shared morphological properties of both the genus Rickettsia and genus Chlamydia. 相似文献
992.
Zola H Swart B Boumsell L Mason DY;IUIS/WHO Subcommittee 《Journal of immunological methods》2003,275(1-2):1-8
The 7th International Workshop on Human Leucocyte Differentiation Antigens (HLDA7) studied a number of newly characterised molecules relevant to human leucocyte differentiation and function. The HLDA organisation, which devised and continues to maintain the CD nomenclature, is responsible, under the auspices of IUIS and WHO, for the nomenclature of all leucocyte differentiation markers. The 7th Workshop redefined a number of (principally carbohydrate) molecules, and assigned CD names to approximately 80 new molecules. This update lists, in tabular form, the redefined and newly assigned names, together with antibodies, which have been confirmed under Workshop conditions as specific for the new and redefined molecules. The major features of the cellular expression patterns are summarised, and a LocusLink accession number provided to enable the reader to access more detailed information through http://www.ncbi.nlm.nih.gov/LocusLink. 相似文献
993.
Pajot A Pancré V Fazilleau N Michel ML Angyalosi G Ojcius DM Auriault C Lemonnier FA Lone YC 《International immunology》2004,16(9):1275-1282
Transgenic mice expressing human HLA class II molecules provide a useful model for identifying HLA-restricted CD4+ epitopes. However, the influence of endogenous murine H-2-restricted T cell responses on HLA-restricted responses is not known. In the present study, we show that HLA-DR1 transgenic mice deficient for H-2 class II expression (HLA-DR1+/+/IAbeta0/0) exhibit an equivalent expression level of the transgene HLA-DR1 and a similar diversity in the TCR repertoire, but a slightly different number of CD4+ peripheral T cells, when compared to HLA-DR1 transgenic mice in which H-2 class II molecules were retained (HLA-DR1+/+/IAbeta+/+). More importantly, a strong antigen-specific HLA-DR1-restricted response was observed in nearly all HLA-DR1+/+/IAbeta0/0 mice immunized with HBV envelope protein (HBs) or capsid protein (HBc), whereas weak HBs- or HBc-specific HLA-DR1-restricted responses were detected in half of the immunized HLA-DR1+/+/IAbeta+/+ mice. Conversely, strong HBs- or HBc-specific H-2-restricted T cell responses were detected in HLA-DR1+/+/IAbeta+/+ mice but not in HLA-DR1+/+/IAbeta0/0 mice. Our results indicate that the coexpression of endogenous H-2 class II molecules reduces the intensity of HLA-DR1-restricted antigen-specific responses in transgenic mice, by favoring murine over human MHC recognition and education. Thus, HLA-DR1+/+/IAbeta0/0 mice represent a better model for identifying and characterizing HLA-DR1-restricted epitopes relevant for human disease. 相似文献
994.
Guarner J Greer PW Whitney A Shieh WJ Fischer M White EH Carlone GM Stephens DS Popovic T Zaki SR 《American journal of clinical pathology》2004,122(5):754-764
Neisseria meningitidis remains the leading cause of fatal sepsis. Cultures may not be available in fulminant fatal cases. An immunohistochemical assay for N meningitidis was applied to formalin-fixed samples from 14 patients with meningococcal disease. Histopathologic findings in 12 fatal cases included interstitial pneumonitis, hemorrhagic adrenal glands, myocarditis, meningitis, and thrombi in the glomeruli and choroid plexus. Meningeal inflammation was observed in 6 patients. Skin biopsies of 2 surviving patients showed leukocytoclastic vasculitis and cellulitis. By using immunohistochemical analysis, meningococci and granular meningococcal antigens were observed inside monocytes, neutrophils, and endothelial cells or extracellularly. By using real-time polymerase chain reaction (PCR) on formalin-fixed tissue samples, meningococcal serogroup determination was possible in 11 of 14 cases (8 serogroup C, 2 Y, and 1 B). Diagnosis and serogrouping of N meningitidis can be performed using immunohistochemical analysis and PCR on formalin-fixed tissue samples. Immunohistochemical analysis determined the distribution of meningococci and meningococcal antigens in tissue samples, allowing better insights into N meningitidis pathogenesis. 相似文献
995.
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
996.
Gonadoblastoma is a rare tumor arising in the streak gonads of about 30% of 46, XY sex-reversed females. Because gonadoblastoma develops only in patients who have Y-chromosome material and dysgenetic gonads, it has been hypothesized that positive expression of a gene (or genes) on the Y chromosome (GBY) is involved in the etiology of the tumor. To examine the Y chromosome directly in tumors, we performed nonisotopic in situ hybridization of a biotin-labeled Y-specific probe for the DYZI locus on formalin-fixed, paraffin-embedded sections of tumor samples from four different patients. After hybridization to DYZI, the Y chromosome was found to be present in all gonadoblastoma foci in the four patients studied, and the gonadoblastoma foci showed an average of 85% cell nuclei positive for the Y chromosome on tissue sections. Normal male and female control tissues showed an average of 78% and 0% positive nuclei, respectively. One patient with bilateral gonadoblastoma had previously been shown to be mosaic, with a 45, X/46, XY karyotype in lymphocytes, skin fibroblasts, and cultures from both gonads. Examination of sections of this patient's gonads showed 79% positive nuclei within the gonadoblastoma foci, whereas the nontumor stromal tissue had 19% positive nuclei. These results indicate that, in this mosaic gonad, tumor foci developed only from cells that had a Y chromosome. Our results support the hypothesis that there is a GBY locus on the Y chromosome and that the Y chromosome is retained in the gonadoblastoma foci during the development of the tumor. © 1995 Wiley-Liss, Inc. 相似文献
997.
998.
999.
David Friedman Lois Putnam Walter Ritter Marla Hamberger Steven Herman 《Psychophysiology》1992,29(5):593-609
Event-related potentials were recorded in a developmental study of picture matching using an adaptation of Posner's (1978) letter-matching tasks. Subjects ranging in age from 6-39 were asked to decide whether two line drawings, presented sequentially, were the same or different on the basis of physical (physical identity), nominal (name identity), or categorical (category identity) criteria. The amplitude of a negativity at 400 ms (Neg400) increased as the number of dimensions on which the two line drawings differed increased. This effect held for all age groups, and was interpreted as reflecting the degree of semantic and/or physical relationship between the two pictures. However, one finding for Neg400 did suggest a qualitative difference in processing mode between the younger and older subjects. Both Neg400 and P3b latencies showed highly significant linear age trends, decreasing with increasing age. These age-related changes were interpreted as demonstrating quantitative speed of processing differences among age groups. The latencies of both Neg400 and P3b increased as the matching criteria became more complex. Moreover, P3b latency increased as the number of dimensions on which the two pictures differed increased, and this did not interact with age. Although both Neg400 and P3b showed age-related changes in scalp distribution, the fact that each was related to the experimental variables in similar fashion in all age groups suggested that they were homologous components across the age range studied. Taken as a whole, the data support continuity of information processing during these tasks across a wide age range. 相似文献
1000.