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51.
There is uncertainty about the relation between 24-h urinary uric acid excretion and the risk of calcium oxalate nephrolithiasis. In addition, the risk associated with different levels of other urinary factors needs clarification. We performed a cross-sectional study of 24-h urine excretion and the risk of kidney stone formation in 3350 men and women, of whom 2237 had a history of nephrolithiasis. After adjusting for other urinary factors, urinary uric acid had a significant inverse association with stone formation in men, a marginal inverse association with risk in younger women, and no association in older women. The risk of stone formation in men and women significantly rose with increasing urine calcium and oxalate, and significantly decreased with increasing citrate and urine volume, with the change in risk beginning below the traditional normal thresholds. Other urinary factors were also associated with risk, but this varied by age and gender. Our study does not support the prevailing belief that higher urine uric acid excretion increases the risk for calcium oxalate stone formation. In addition, the current definitions of normal levels for urinary factors need to be re-evaluated. 相似文献
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Sir, We read with interest the report by Jungers et al [1]. in theSeptember issue of NDT. The authors compared their results withour earlier publication [2]. 相似文献
54.
Among the many effects of family planning is the influence ithas on mortality and morbidity in women and children throughthe mechanism of changing the number and spacing of children.There is a complex set of relationships between mother's age,parity, birth spacing and infant and child mortality and morbidity.Much effort has been put into untangling this web in the hopeof identifying clear causal connections, but for the most parton the basis of inadequate data. Rather than attempt to establishthe relative importance of child spacing as a cause of decreasesin mortality, this paper takes as its starting point that thereis a connection, and presents some possible causal mechanismswhich explain how short birth intervals and child mortalitycould be related. In addition the most frequently cited hypotheses-maternaldepletion and sibling competition-a third is examined-birthcrowding which, it is suggested, influences the pattern of thetransmission of infectious diseases and, in turn, mortality. In the field of maternal mortality, the data which could beused to quantify the benefits of family planning are in evenshorter supply; however, the causal connections are rather moreeasily identified. The final section combines parity-specificdata on maternal mortality with evidence of changes in fertilitypatterns brought about by family planning to assess how successfulwe can hope to be in reducing through birth control the numberof women who die in childbirth. 相似文献
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Recovery of T cell subsets after autologous bone marrow transplantation is mainly due to proliferation of mature T cells in the graft 总被引:3,自引:3,他引:3
de Gast GC; Verdonck LF; Middeldorp JM; The TH; Hekker A; v.d. Linden JA; Kreeft HA; Bast BJ 《Blood》1985,66(2):428-431
In 22 patients with malignancies, treated with high-dose chemoradiotherapy and autologous bone marrow transplantation (BMT), peripheral blood T cell subsets and functions were studied. In ten cytomegalovirus (CMV)-negative patients, CD4+ and CD8+ T cells (representing T cells of the helper/inducer phenotype and T cells of the suppressor/cytotoxic phenotype, respectively), recovered slowly and simultaneously. In 12 CMV-positive patients, however, CD8+ T cells recovered more rapidly than CD4+ T cells and rose to increased counts. No T cells with an immature phenotype (CD1+, OKT6+) were observed. Lymphocyte stimulation by herpes simplex virus infected fibroblasts (and by CMV-infected fibroblasts in CMV-positive patients) in contrast remained high and even increased after BMT in both groups. These data indicate that T cell recovery after autologous BMT is mainly due to proliferation of mature T cells present in the BM graft and not to generation of new T cells from T cell precursors. 相似文献
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Hematopoietic growth factor receptors are present on cells of normal nonhematopoietic tissues such as endothelium and placenta. We previously demonstrated functional human granulocyte-macrophage colony- stimulating factor (GM-CSF) receptors on small cell carcinoma of the lung cell lines, and others have reported that certain solid tumor cell lines respond to GM-CSF in clonogenic assays. In the current study, we examine human melanoma cell lines and fresh specimens of melanoma to determine whether they have functional GM-CSF receptors. Scatchard analyses of 125I-GM-CSF equilibrium binding to melanoma cell lines showed a mean of 542 +/- 67 sites per cell with a kd of 0.72 +/- 0.14 nmol/L. Cross-linking studies in the melanoma cell line, M14, showed a major GM-CSF receptor species of 84,000 daltons. Under the conditions tested, the M14 cells did not have a proliferative response to GM-CSF in vitro, nor was any induction of primary response genes detected by Northern analysis in response to GM-CSF. Studies to determine internal translocation of the receptor-ligand complex indicated less than 10% of the 125I-GM-CSF internalized was specifically bound to receptors. Primary melanoma cells from five surgical specimens had GM-CSF receptors; Scatchard analysis was performed on one sample, showing 555 sites/cell with a kd of 0.23 nmol/L. These results indicate that human tumor cells may express a low-affinity GM-CSF receptor protein that localizes to the cell surface and binds ligand, but lacks functional components or accessory factors needed to transduce a signal. 相似文献
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Eelco AB Over GC Wanda Wendel-Vos Matthijs van den Berg Heleen H Hamberg-van Reenen Luqman Tariq Rudolf T Hoogenveen Pieter HM van Baal 《Cost effectiveness and resource allocation : C/E》2012,10(1):1-7