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31.
Down-regulation of mannosyl receptor-mediated endocytosis and antigen F4/80 in bacillus calmette-guerin-activated mouse macrophages. Role of T lymphocytes and lymphokines 总被引:2,自引:1,他引:2 下载免费PDF全文
Bacillus Calmette-Guerin (BCG) infection alters the surface and endocytic properties of mouse peritoneal macrophages (PM) compared with thioglycollate- elicited (TPM) or resident PM (RPM). Expression of Ia antigen (Ag) is enhanced up to fourfold, but plasma membrane receptors that mediate binding and uptake of mannosyl/fucosyl-terminated glycoconjugates (MFR), Fc receptors, and the macrophage (m)-specific Ag F4/80 are reduced by 50-80 percent. Levels of Mac-1 remain relatively stable. These changes are accompanied by enhanced secretion of O(2)(-), after further stimulation with phorbyl myristate acetate, and of plasminogen activator. Both these products are released by TPM, but not RPM. The characteristic surface phenotype of BCG-PM can also be induced by injection of C. parvum, another m- activating agent, but not by thioglycollate broth, lipopolysaccharide, or proteose peptone. Purified protein derivative (PPD) and N-acetylmuramyl-L- alanyl-D-isoglutamine. 2H(2)0 are soluble agents with partial activity. Alteration of m markers by BCG infection depends on T lymphocyte function, although studies with nude mice indicate that other pathways may also serve to modify the surface of the m. M from uninfected animals displayed all markers of activation after adoptive transfer of specifically-sensitised lymphocytes with PPD, intraperitoneally, or after co- cultivation. Treatment of primed lymphocytes with anti-Thy-1 antibody and complement ablated this effect. Lymphokines obtaned by Ag or mitogen stimulation induced similar changes in TPM and RPM. Mannose-specific endocytosis decayed rapidly, time 1/2 approximately equal to 16 h and stabilized at approximately 25 percent of control values. Single-cell analysis showed that residual MFR activity was uniform in the target population. Loss of Ag F4/80 after activation by lymphocyte and PPD was less marked than after infection (35 percent vs 80 percent), unlike MFR activity, which declined to a similar extent. Induction of m Ia by lymphokine reached a peak after 2-3 d and was lost within 2 d of its removal. Recovery of MFR and F4/80 was incomplete under these conditions. These studies establish that activated m known to display enhanced antimicrobial/anticellular activity express markedly different surface properties distinct from elicited or resident cells. The role of antigen- stimulated T cell products in regulating m function is confirmed, and down-regulation of mannosyl-receptor-mediated endocytosis provides a sensitive, quantitative, and cell-specific new marker to study their properties and mechanism of action. Extensive, but selective remodeling of m plasma membrane structure could play an important role in controlling recognition and effector mechanisms of the activated m. 相似文献
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Background
Tamoxifen, used as adjuvant therapy for carcinoma breast in postmenopausal women to prevent relapse has estrogenic effect on the endometrium.Methods
104 patients on tamoxifen for more than six months were subjected to a clinical examination and transvaginal sonography. Patients with endometrial thickness > 8 mm were further evaluated by hysteroscopy and endometrial biopsy.Results
35(34%) patients were symptomatic. The average endometrial thickness was 11.2 mm which correlated with duration of tamoxifen use. 27(48%) patients had abnormal hysteroscopic findings. 35 (63%) of endometrial biopsies revealed abnormal endometrium. One case of endometrial carcinoma was diagnosed. The results were statistically analysed. There is a significant association between symptomatic status and endometrial thickness and duration of tamoxifen use.Conclusion
All patients on long term tamoxifen should be annually screened for endometrial pathology.Key Words: Tamoxifen, Endometrium, Transvaginal sonography 相似文献36.
KATHLEEN B. SCANLON AB MSN LAWRENCE J. GRYLACK MD MOISES BORTEN MD 《Journal of obstetric, gynecologic, and neonatal nursing : JOGNN / NAACOG》1982,11(6):355-358
Placement of umbilical artery catheters was retrospectively reviewed in 181 newborns to evaluate random placement of catheter tip in the "high" position between T7 and T9 in the thoracic aorta of 127 infants and in the "low" position below 4 in the abdominal aorta of 54 infants. Group differences in gestational age, asphyxia, hypotension, respiratory disease, duration of catheterization, or infusate type were not significant. Cyanosis or blanching in the low extremities occurred in 67% of the "low" group and 21% of the "high" group ( P < .001). Hematuria occurred in 39% of the "low" group and 21% of the "high" group ( P < .05). High placement appears to have fewer complications. Prompt intervention by neonatal nurse practitioners can help reverse complications that occur during umbilical artery catheterizations. 相似文献
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产后出血的预防和处理指南 总被引:3,自引:0,他引:3
目的:为产后出血(PPH)的预防和临床处理作一综述,为临床医师提供预防和处理产后出血的指南。涉及方面:预防、适当干预、使其影响最小化的方法。结果:建立常规,便于临床医师鉴别可能的高危人群,一旦发生产后过多出血,可指导临床如何迅速处理。证据:遵循加拿大定期健康检查办公室制定的证据等级。评估:由产科专家完善。利弊和成本:评估子宫收缩药和其他积极处理措施的方便性、正确性、有效性和安全性。建议:根据证据的等级,本指南分等级列出了12条建议。确认:按照MeSH词表推荐的postpartum haemorrhage在medline上查询相关文献,在Cochrane图书馆查找相关研究文献,并参考the ALARMcourse Manual。发起人:由产科临床实践委员会制定和综述,并由SOGC(加拿大妇产科协会)委员会批准。 相似文献
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