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Style guides, the primary tool of technical editors, are as important as ever; actually, their increased uses and benefits can redefine the activities of editors. Specifically, style guides can be used to train new employees, to generate buy-in of subject-matter experts, and to define the process flow of document and product generation. Additionally, because they have the potential to control many style decisions and to integrate a variety of skills, computer-driven styles and Web style guides reinforce these increased uses and benefits and suggest the emergence of even more. Thus technical editors' roles may be expanded to include additional training functions, new marketing dimensions, and innovative research in multimedia design and development 相似文献
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WR Bell 《Canadian Metallurgical Quarterly》1996,22(6):459-478
During activation of the fibrinolytic system plasminogen is converted to plasmin by tissue plasminogen activator (t-PA) or urokinase-type plasminogen activator (u-PA). t-PA is predominantly released from endothelial cells, u-PA primarily by renal parenchymal cells. The activation of plasminogen is regulated by plasminogen activator inhibitor-1 (PAI-1), plasmin is controlled by alpha 2-plasmin inhibitor. The fibrinolytic system is not only involved in the intravascular dissolution of fibrin (thrombi), it also plays a vital role in normal physiologic reproduction, wound repair, angiogenesis, and tissue remodeling. Fibrinolysis is also a vital component in the pathogenesis of neoplastic disease. It is essential in releasing cells from their primary site of origin, providing nutrition for neoplastic cell growth and promoting cell mobility and motility. In neoplastic cells the degradation of the extracellular matrix proteins is facilitated by excessive expression of u-PA, t-PA, and u-PAR. In many forms of carcinoma increased expression of u-PAR and u-PA is associated with significantly shorter survival. Greater expression of u-PA in breast cancer cells, for example, is associated with shorter survival and increased relapse rate. Progressively aggressive neoplastic cells evidence high expression of u-PA and u-PAR activities, variable expression of t-PA, and enhanced PAI-1 and PAI-2 activities. In acute nonlymphocytic leukemias, poor outcome correlates with high t-PA levels. In acute progranulocytic leukemia there is a high incidence of DIC. Neoplastic prostatic tissue also expresses high u-PA activity and the more aggressive the cell line, the greater the number of u-PAR and the higher the u-PA activity. In gynecologic malignancies, a greater expression of u-PA in combination with cathepsin D is associated with widespread disease and poor prognosis. High u-PA values were also seen in patients with brain, gastric, and hepatic malignancies. It is evident that the plasminogen-plasmin system is a vital component in the biology of neoplastic disease and that it is, in theses conditions, in no way beneficial to the host. 相似文献
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RE Sacco JS Haynes JA Harp WR Waters MJ Wannemuehler 《Canadian Metallurgical Quarterly》1998,153(6):1717-1722
Flora-bearing mice with targeted disruption of T cell receptor (TCR)-alpha or -beta genes spontaneously develop intestinal inflammation with features similar to ulcerative colitis in humans. TCR-alpha-deficient mice maintained germfree or colonized with a limited number of intestinal bacteria failed to develop inflammatory bowel disease (IBD)-like lesions. Evidently, inflammation in these mice does not develop spontaneously or result from a generalized antigenic stimulation, but rather requires induction by a heretofore unidentified specific stimulus. We describe the development of IBD-like lesions in germfree TCR-alpha-deficient mice monoassociated with the protozoan Cryptosporidium parvum. Lesions were seen in distal ileum, cecum, and colon and were most severe in the cecum. A prominent leukocytic infiltrate within the lamina propria was a common characteristic of the lesions observed in the C. parvum-infected germfree TCR-alpha-deficient mice. The leukocytic infiltrate was composed of aggregates of B220+ cells, the majority of which expressed surface IgD (ie, conventional B lymphocytes). It has been proposed that antigenic stimulation by a microorganism(s) is needed to initiate intestinal inflammation in TCR-alpha-deficient mice. Our results indicate that a single microbial species, C. parvum, is capable of triggering the development of IBD-like lesions in germfree TCR-alpha-deficient mice. 相似文献
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The extensive heterogeneity of the gonadotrophin hormones, follicle stimulating hormone (FSH) and luteinizing hormone (LH), is due primarily to the heterogeneous nature of their carbohydrate side-chains, in particular sialic acid residues. In this review, we discuss the role of carbohydrate chains in receptor binding and activation, biological activity, and metabolic half-life. The synthesis and secretion of the various glycoforms of both FSH and LH appear to be under endocrine control with gonadotrophin-releasing hormone (GnRH), oestradiol and testosterone playing important roles. Evidence for different glycoforms having variable biopotency or different encoded functions is increasing, and the production and secretion of more or less acidic gonadotrophin species in different physiological states may represent an important mechanism whereby the pituitary regulates gonadal cell and organ function. This has potential importance for the development of new pharmaceutical reagents and new therapeutic regimens in assisted reproduction. It is envisaged that the use of existing and new forms of FSH/LH will allow patients to be treated in a more controlled and physiological manner, with treatment regimens individualized to the needs of the patient. 相似文献
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WR Bishai NM Graham S Harrington DS Pope N Hooper J Astemborski L Sheely D Vlahov GE Glass RE Chaisson 《Canadian Metallurgical Quarterly》1998,280(19):1679-1684
Stevioside is a sweet-tasting glycoside, composed of stevia, a diterpenic carboxylic alcohol with three glucose molecules, mainly used as a substitute for non-alcoholic sweetener. It has previously been shown to reduce blood pressure in studies in animals and human. The effect of intravenous stevioside on the blood pressure was studied in spontaneously hypertensive rats (SHR). The hypotensive effect on both systolic and diastolic blood pressure was dose-dependent for intravenous doses of 50, 100 and 200 mg/kg in conscious SHR. The maximum reductions in systolic and diastolic blood pressure were 31.4 +/- 4.2% and 40.8 +/- 5.6% (mean +/- SEM) respectively and the hypotensive effect lasted for more than 60 min with a dose of 200 mg/kg. Serum dopamine, norepinephrine and epinephrine levels were not changed significantly 60 min after intravenous injection of stevioside 100 mg/kg in anesthetized SHR. The present data show that stevioside given intravenously to conscious SHR was effective in blood pressure reduction and there was no change in serum catecholamines in anaesthetized animals with this natural compound. 相似文献
40.
Asmaa A. Zidan Mohammed Al-Hawwas Griffith B. Perkins Ghada M. Mourad Catherine J. M. Stapledon Larisa Bobrovskaya Xin-Fu Zhou Plinio R. Hurtado 《International journal of molecular sciences》2021,22(1)
Elucidation of the biological functions of extracellular vesicles (EVs) and their potential roles in physiological and pathological processes is an expanding field of research. In this study, we characterized USC–derived EVs and studied their capacity to modulate the human immune response in vitro. We found that the USC–derived EVs are a heterogeneous population, ranging in size from that of micro–vesicles (150 nm–1 μm) down to that of exosomes (60–150 nm). Regarding their immunomodulatory functions, we found that upon isolation, the EVs (60–150 nm) induced B cell proliferation and IgM antibody secretion. Analysis of the EV contents unexpectedly revealed the presence of BAFF, APRIL, IL–6, and CD40L, all known to play a central role in B cell stimulation, differentiation, and humoral immunity. In regard to their effect on T cell functions, they resembled the function of mesenchymal stem cell (MSC)–derived EVs previously described, suppressing T cell response to activation. The finding that USC–derived EVs transport a potent bioactive cargo opens the door to a novel therapeutic avenue for boosting B cell responses in immunodeficiency or cancer. 相似文献