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991.
992.
Ann McNicholas Yao Z M Hammond E Dondi MC Cuccia A. Bartova J Drabek D. Chandanayingyong ED Albert 《Human immunology》1996,47(1-2):9
We have investigated the distribution of HLA-B44 subtypes in various populations, see table. Of the five B44 subtypes investigated, two are apparently quite rare because they were only found in the local central european panel (B*4404 and B*4406). The european populations are characterized by a relatively high frequency of B*4402, while in the Albanian, in the Asiatic and African populations, the subtype B*4403 is prevailing. The distribution of the B44 subtypes in the Czech and the Munich population are virtually the same. We conclude from these data, that B44 subtypes have different distributions in different populations of the world and must therefore be taken into consideration when matching for bone marrow transplantation. 相似文献
993.
Mark A. Greenberg M.D. CPT MC Clark R. Kaufman M.D. MAJ MC Gabriel E. Gonzalez M.D. MAJ >MC Cheryl D. Rosenblatt M.D. LCDR MC Laurie J. Smith M.D. Richard J. Summers M.D. COL MC 《The Journal of allergy and clinical immunology》1986,77(6):865-870
Systemic-allergic reactions to allergen immunotherapy were prospectively studied in four allergy treatment centers to assess frequency and specific attributes of these episodes relative to several variables. A total of 20,588 extract injections were administered to 628 patients. Forty-two patients experienced a systemic reaction (7%). Fifty-two systemic reactions occurred in total. Eight patients accounted for 18 of the reactions. Late systemic reactions, occurring from 35 minutes to 6 hours after injection, accounted for 38% of all reactions. Extracts containing only pollen antigens were more commonly associated with immediate and late systemic reactions relative to other extracts (p less than 0.001 and p less than 0.01, respectively). There were no significant reaction-rate differences whether immunotherapy was at maintenance or increasing doses or if the time of injection was during a pollinating or nonpollinating season. The most common clinical manifestations of the systemic reactions were generalized pruritus and urticaria. We conclude that patients receiving extracts containing only pollen antigens have increased systemic-allergic reaction rates. A subgroup of patients are at risk for recurrent reactions. Finally, late systemic reactions to immunotherapy are not rare events and pose a definite risk to the individual patient. 相似文献
994.
995.
Morankinyo Oyewole Toney MC Rodrigo Dominguez Huu-Ninh Dao Gary Simmons 《Journal of digital imaging》1997,10(4):169-173
Extensive research efforts have been devoted to the feasibility of picture archiving and communication systems (PACS) in recent years. The advantages of PACS are numerous but mainly include reduced cost and improvement in the operational efficiency of a PACS-based radiology department. In digital radiography, images are viewed either in hard-copy or soft-copy format. Usually, these images are subsequently compressed and archived for future evaluation. There are various methods used in image compression. In this study, computed radiography images showing subtle pediatric bone fractures were compressed with the lossy method of image compression after they had been initially evaluated on workstation monitors. These studies were subsequently evaluated by observers, who were unaware of the interpretations of these images before compression, to determine if they could detect similar abnormalities. Our conclusion is that there is no difference in the interpretation of soft-copy computed radiographic images before or after lossy 10∶1 compression in studies of subtle pediatric bone fractures. This is a US government work. There are no restrictions on its use. 相似文献
996.
Positive selection of cytotoxic T lymphocyte escape variants during acute hepatitis C virus infection 总被引:2,自引:0,他引:2
Guglietta S Garbuglia AR Pacciani V Scottà C Perrone MP Laurenti L Spada E Mele A Capobianchi MR Taliani G Folgori A Vitelli A Ruggeri L Nicosia A Piccolella E Del Porto P 《European journal of immunology》2005,35(9):2627-2637
Cellular immune responses are induced during hepatitis C virus (HCV) infection and acute-phase CD8+ T cells are supposed to play an important role in controlling viral replication. In chimpanzees, failure of CD8+ T cells to control HCV replication has been associated with acquisition of mutations in MHC class I-restricted epitopes. In humans, although selection of escape mutations in an immunodominant CTL epitope has been recently described, the overall impact of immune escape during acute HCV infection is unclear. Here, by performing an in depth analysis of the relationship between early cellular immune responses and viral evolution in a chronically evolving HCV acutely infected individual, we demonstrate: (i) the presence of a potent and focused CD8(+ T cell response against a novel epitope in the NS3 protein, (ii) the elimination of the quasi-species harboring the original amino acid sequence within this epitope, and (iii) the selection for a virus population bearing amino acid changes at a single residue within the cytotoxic T cell epitope that strongly diminished T cell recognition. These results support the view that acute-phase CD8+ T cell responses exert a biologically relevant pressure on HCV replication and that viruses escaping this host response could have a significant survival advantage. 相似文献
997.
Transrectal electroejaculation combined with in-vitro fertilization: effective treatment of anejaculatory infertility due to spinal cord injury 总被引:1,自引:0,他引:1
Brinsden PR; Avery SM; Marcus S; Macnamee MC 《Human reproduction (Oxford, England)》1997,12(12):2687-2692
Infertility due to spinal cord injury (SCI) in young men is a frequent
complication of their injury. When the simpler methods of management of the
erectile and ejaculatory dysfunction that invariably follow the more severe
types of SCI are not effective, then semen production by transrectal
electroejaculation (TREE) combined with in-vitro fertilization (IVF) and
embryo transfer is effective. A retrospective analysis is presented of data
on the treatment and outcome of 35 couples who wished to have a family but
in whom the male partner had suffered SCI. These 35 couples had 71 attempts
at IVF with spermatozoa obtained following TREE. Normal fertilization and
cleavage of the embryos occurred in 48.2% of the oocytes. Fresh embryos
were transferred in 54 cycles and frozen-thawed embryos in 14 cycles. In
all, 18 clinical pregnancies were achieved in 54 fresh and 14 frozen embryo
transfer cycles, with a live birth rate of 16.5% (14/85) per treatment
cycle started, 20.6% (14/68) per transfer cycle and 40.0% (14/35) per
couple who started treatment, in a mean of 1.9 transfer cycles. We conclude
that TREE combined with IVF and embryo transfer is an effective treatment
for the infertility problems associated with SCI.
相似文献
998.
999.
Giuseppe A. Marraro Carmelo Denaro Claudio Spada Marco Luchetti Carla Giansiracusa 《Journal of clinical monitoring and computing》2010,24(1):73-81
Objective
Open lung and low tidal volume ventilation appear to be a promising ventilation for chest trauma as it can reduce ARDS and improve outcome. Local therapy (e.g. BAL) can be synergic to remove from the lung the debris, mitigate inflammatory cascade and avoid damage spreading to not compromised lung areas. 相似文献1000.
Captain Richard H. Rahe MC USNR Dr. Ransom J. Arthur M.D. 《Behavioral medicine (Washington, D.C.)》2013,39(1):3-15
Abstract A selected review of life changes and illness studies is presented which illustrates both the diversity of samples that have been tested in these studies and the generally positive results which have been obtained. Although early (retrospective) work in this field led to simplistic explanations, later (prospective) studies have begun to document the several intervening variables which occur between subjects' recent life change experiences and their subsequent symptomatology and disease. A life change and illness model is presented to illustrate key intervening variables. The authors believe that future research in the field of life change and illness should concentrate on further delineations of these intervening variables — an effort necessitating active collaboration between social and medical scientists. 相似文献