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51.
Induction of immunoglobulin secretion in follicular non-Hodgkin's lymphomas: role of immunoregulatory T cells 总被引:2,自引:0,他引:2
B cell neoplasms are clonal expansions of B lymphocytes thought to be frozen at various points along the normal B cell differentiation pathway. We studied cell suspensions from lymph nodes involved by follicular (nodular) non-Hodgkin's lymphoma to determine the capacity of the malignant B cells to secrete immunoglobulin (Ig). Neoplastic B cells from all 14 follicular lymphomas secreted monoclonal immunoglobulin in culture when appropriate signals were provided. In most cases, maximal Ig secretion occurred when autologous T cells were removed by E rosette depletion, replaced with allogeneic normal T cells, and the cultures were exposed to 12-O-tetradecanoylphorbol-13- acetate. Autologous T cells exerted a suppressor effect on Ig secretion in 8/8 cases studied, diminishing the response of the malignant B cells to allogeneic T cells. This suppressor effect did not correlate with the percentage of cells staining with anti-Leu-2a or with "helper- suppressor" (Leu-3a-Leu-2a) ratios of the lymph node T cells. Our findings demonstrate that the arrested differentiation of most follicular lymphomas is reversible and implicate a T cell-mediated host immunoregulatory mechanism affecting Ig secretion in vivo. An additional contribution of our results is the demonstration of a cell culture system for synthesis of sufficient monoclonal Ig for use as an immunogen in production of anti-idiotype antibodies. 相似文献
52.
The platelet-derived growth factor (PDGF) has several well defined important biologic activities. Platelet-derived growth factor is the major mitogen in human serum for cells of mesenchymal origins; it is a potent chemoattractant protein for human monocytes, neutrophils, fibroblasts, and smooth muscle cells; and has been implicated in transformation by simian sarcoma virus and perhaps in transformation by other agents as well. In this article, PDGF has been shown to stimulate activation of human peripheral blood neutrophils defined by loss of membrane associated calcium as reflected by loss of chlortetracycline fluorescence, release of superoxide anion and specific granule enzymes, and enhanced neutrophil adherence and aggregation. These responses occurred in a dose-dependent fashion at concentrations of PDGF between 10 ng/mL (0.4 nmol/L) and 40 ng/mL (1.5 nmol/L) and were comparable to effects obtained with optimal concentrations of fMLP and C5a. Degranulation induced by PDGF was selective for secondary (specific) granules and not primary (azurophil) granules. Platelet-derived growth factor thus is ideally suited for a pivotal role in attracting inflammatory cells locally and initiating neutrophil activation at sites of blood vessel injury. Platelet-derived growth factor or a closely related protein also may play an important role in attracting and activating neutrophils in association with inflammatory tumors. 相似文献
53.
Protection of ovarian function by oral contraceptives in women receiving chemotherapy for Hodgkin's disease 总被引:4,自引:0,他引:4
It has been reported by us and by others that after chemotherapy for Hodgkin's disease the ovary contains fewer than 5 primordial and primary follicles per 5 x 5 mm biopsy section. In young women this is associated with premature menopause. We report here that before treatment the tissue contains 18--55 such follicles per biopsy section. When women took combination oral contraceptives throughout the course of MVPP therapy, the posttreatment ovarian biopsy tissue had more than 20 follicles per histologic section. Normal menses were established in the five women who discontinued oral contraceptives at the end of MVPP therapy, and one of them is now pregnant. 相似文献
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E. Rosser RN DPhil MN RM Dip N Ed Dip RM PFHEA E. Buckner RN PhD CNE AE-C FNAP T. Avedissian RN MSN D.S.K. Cheung BN MSc PhD K. Eviza RN MSN T. B. Hafsteinsdóttir RN PhD M.Y. Hsu RN PhD MSc M. N. Kirshbaum RN BSc MSc PhD GDip Health Ed Dip Onc Dip Counselling Dip CBT FHEA C. Lai RN PhD Y.C. Ng PhD J. Ramsbotham RN PhD MN S. Waweru RN MSN FNP-BC 《International nursing review》2020,67(4):484-494
56.
Elizabeth Stenhouse RN RM ADM PhD Senior Lecturer Midwifery Research Gayle Letherby BA PhD AcSS Professor of Sociology 《Midwifery》2011,27(2):120-124
In pregnancies complicated by pre-existing diabetes, there is a higher incidence of adverse pregnancy outcome. Several reports including the Confidential Enquiry into Maternal and Child Health, Diabetes in Pregnancy—are we providing the best care? (2007) highlighted the need for family involvement before/during pregnancy and in early motherhood with the aim of making pregnancy and the transition to motherhood a positive and fulfilling experience. Exploring the midwifery, sociological and diabetes literature may assist in gaining a better understanding of the complexities surrounding conception, pregnancy, childbirth and motherhood within the context of diabetes. 相似文献
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59.
Florence Nightingale, feminism and nursing 总被引:1,自引:0,他引:1
Mary E. Holliday RN RM MA PGCEA David L. Parker RGN RMN BN MA Cert Ed 《Journal of advanced nursing》1997,26(3):483-488
Three key aspects of Florence Nightingale's remarkable life are examined. First, the influences during her formative years: the education and guidance provided by her father, the resistance by her family when she decided to become a nurse; and the rejection by Nightingale of the societal expectations of a woman in the Victorian era. Secondly, her professional life is examined, in particular how she appears to have been viewed by certain members of society, and how in turn she viewed them. It is anticipated that her position as an early feminist will be postulated and illuminated. Thirdly, an analysis of her personal and professional life indicates a way forward for the nursing profession. 相似文献
60.
SG Divers ; K Kannan ; RM Stewart ; KW Betzing ; D Dempsey ; M Fukuda ; R Chervenak ; RF Holcombe 《Transfusion》1995,35(4):292-297
BACKGROUND: Platelets become activated during storage, which results in secretion of granules, vesiculation of microparticles, secretion of protein, and a number of other biochemical and morphologic processes that decrease the utility of platelet concentrates stored for transfusion. STUDY DESIGN AND METHODS: To evaluate the quality of stored platelet concentrates, the cell surface expression of specific activation-dependent antigens (CD62 and lysosome-associated membrane proteins 1 and 2 [LAMP-1, LAMP-2]) on platelets stored in a hospital blood bank over a 7-day period was examined. Relative microparticle counts and the expression of CD62 by microparticles, as well as platelet concentrate supernatant levels of soluble CD62, were determined. RESULTS: The percentage of platelets expressing CD62 increased significantly from Day 1 to Day 5 (p < 0.05) of storage; the mean fluorescence values for CD62 did not. In contrast, the mean fluorescence values of LAMP-1 and LAMP-2 rose significantly (p < 0.01 and p < 0.05, respectively) between Days 1 and 5. Significant declines in CD62, LAMP-1, and LAMP-2 percent expression and mean fluorescence were seen on Day 6 of storage (p < 0.001). Microparticle numbers increased significantly during storage and correlated with levels of CD62 protein (free and membrane-bound) (r = 0.95 vs. Day 2, p < 0.05; r = 0.88 vs. Day 5, p < 0.05). CONCLUSION: Flow cytometric evaluations of the expression of cell surface CD62, LAMP-1, and LAMP-2 are complementary tests that, especially when used in conjunction with the quantitation of CD62 protein, provided a simple and effective means of evaluating the quality of platelet concentrates stored for transfusion. 相似文献