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Since sera from most species contain both colony-stimulating and column-inhibitory factors, the net CSA results from a balance between these opposing substances. Studies were performed to determine whether the increased CSA noted during neutropenia or endotoxemia is due to an increase in CSF or to a decline in serum inhibitors. Rats were treated with cyclophosphamide, total body irradiation, or endotoxin and bled during the peak CSA response. By separation studies using Sephadex G150, it was shown that serum levels of high-molecular-weight inhibitors were unchanged from control values. Minimal CSA was detected in normal serum fractions; increased activity was found in fractions from neutropenic animals. During a postcyclophosphamide rebound neutrophilia, serum CSA was undetectable; inhibitor levels were similar to those measured in untreated controls. These observations show that the increased serum CSA seen with neutropenia is due to a true increase in CSF and not to a decline in circulating inhibitors. 相似文献
64.
Isolation and characterization of murine cell surface components. I. Purification of milligram quantities of Thy-1.1 总被引:1,自引:0,他引:1
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The Thy-l.1 molecule was isolated from the BW5147 murine lymphoblastoid cell line. The initial step in purification was the preparation of a crude plasma membrane fraction followed by acetone precipitation. The acetone pellet was solubilized using deoxycholate (DOC) and Thy-1.1 was purified by use of a Lens culinaris lectin affinity column and an AcA-34 gel filtration column. The purified glycoprotein with Thy-1.1 activity had a mol wt of approximately 25,000 daltons. The isolation of this molecule was effected by detecting Thy-I activity utilizing rabbit anti- mouse brain serum tested on rat thymocytes. Congenic anti-Thy-l.1 serum was ineffective in detecting Thy-l.1 after DOC solubilization. An antiserum prepared in rabbits to the purified Thy-1.1 was found to be cytotoxic to mouse and rat thymocytes. The cytotoxic activity of this antisera could be completely absorbed with AKR/Jax brain and thymus but was not absorbed by liver. In addition, AKR/Jax thymocytes totally absorbed all cytotoxic activity of the rabbit anti-purified Thy-1 serum for BW5147 cells suggesting that the cell line shares identical specificities with normal thymocytes. The purified Thy-1.1 molecule was able to totally absorb the cytotoxic activity of mouse congenic anti-Thy-1. These studies serve as a model for the isolation of other murine lymphoid cell surface components in quantities for detailed structural and functional analysis. 相似文献
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ES Dimitry MRCOG M Phil RK Atalla RCOG 《International journal of clinical practice》1996,50(7):376-380
The recent increase in the incidence of ectopic pregnancies was associated with rapid improvement in the diagnostic and therapeutic techniques. Quantitative serum B-HCG radioimmunoassay and high resolution vaginal ultrasonography have facilitated early diagnosis of ectopic pregnancy allowing a more conservative approach to patient management. Different conservative surgical and medical lines of management recently developed were associated with and increased chance of subsequent intrauterine pregnancy with no increase in the incidence of repeat ectopic pregnancy. Outpatient systemic medical treatment seems to be a preferred alternative to conservative surgery. In selected cases, it is associated with a lower complication rate and promising result for fertility. (Br J Clin Pract 1996; 50(7) : 376-380.) 相似文献
68.
跟骨定量超声骨质测量参数与骨密度及骨组织形态计量学指标的关系 总被引:1,自引:0,他引:1
目的:分析跟骨定量超声骨质测量中各参数与骨密度及形态计量学指标的相关性。方法:选择2004-01/2005-12广州市第六人民医院和中山大学三院骨科小腿以上截肢患者38例,将其跟骨定量超声测定的超声振幅衰减平均值与健康青年人骨峰值进行比较,>-2.5 SD者为骨量正常组(12例),<-2.5 SD者为骨质疏松组(26例)。分别进行跟骨定量超声、双能X线骨密度测量仪及骨形态计量学测量,应用直线相关分析法分析跟骨定量超声测定中各参数与骨密度及骨组织形态计量学各指标的相关性。结果:38例全部进入结果分析。①骨质疏松组跟骨超声振幅衰减平均值和骨硬度指数值均小于骨量正常组(P<0.01)。②骨量正常组跟骨骨密度值显著高于骨质疏松组[(352±16),(233±14)mg/cm2,P<0.01]。③骨量正常组跟骨平均骨小梁间距或弥散度低于骨质疏松组而松质骨体积高于骨质疏松组(P<0.05)。④超声振幅衰减平均值和骨硬度指数与骨密度呈直线正相关(r=0.814,0.326,P<0.01,0.05)。⑤超声传播速度与骨小梁游离末端、平均骨小梁间距呈直线负相关(r=-0.688,-0.712,P<0.01),与小梁间连点数、松质骨体积呈直线正相关(r=0.672,0.794,P<0.01);骨硬度指数与平均骨小梁间距呈直线负相关(r=-0.358,P<0.05),与松质骨体积呈直线正相关(r=0.513,P<0.01)。结论:跟骨定量超声测量中,超声振幅衰减平均值能较好地反映骨的密度,超声传播速度能较好地反映骨的质量,而骨硬度指数能较综合地反映骨强度的改变。 相似文献
69.
Hematopoietic factor production by a cell line (TC-1) derived from adherent murine marrow cells 总被引:9,自引:0,他引:9
An adherent cell line, termed TC-1, has been isolated from long-term liquid culture of murine marrow cells by repeated exposure of the adherent cells to 0.1% trypsin. This is an alkaline phosphatase-positive cell line showing variable staining with acid phosphatase and alpha-naphthyl acetate esterase. On electron microscopy, the cells have moderate amounts of rough endoplasmic reticulum and variable numbers of polyribosomes. Some cells contain large clusters of laked glycogen particles. Intermediate junctions are present between some cells. Conditioned medium from this cell line produced from 384 to 638 units of CSF-1 per milliliter by radioimmunoassay and a CSF-1-dependent synergistic activity, which stimulates giant macrophage colony formation of marrow cells in soft agar. The conditioned medium also stimulates 3H-TdR incorporation by marrow cells in liquid culture and induces secondary adherent cell lines. The growth factor(s) produced by the TC-1 stromal cell line may be important in the regulation of early stages of hematopoietic differentiation. Two subclones, TC-1-C-11 and TC-1-C-3, have been isolated from passage 25 of the TC-1 cells by a penicylinder separation technique. The TC-1-C-11 is phenotypically like the parent TC-1 line and produces macrophage growth factors. The TC-1-C-3 grows as an epithelioid monolayer with visible junctions among adjacent cells under phase contrast microscopy. This subclone produces retrovirus and is capable of providing anchorage support for hematopoietic stem cells. The TC-1 cell line and its subclones may provide models for the control of early stem cell proliferation and differentiation. 相似文献
70.
R K Shadduck A Winkelstein Z Zeigler J Lichter M Goldstein M Michaels B Rabin 《Experimental hematology》1979,7(5):264-271
A 17-year-old female developed severe aplastic anemia following serologically proven infectious mononucleosis. In vitro studies, using the granulocyte colony forming technique, suggested that the aplasia may have resulted from an immune mechanism. The patient's marrow grew no granulocyte colonies and caused inhibition of colony formation when mixed with normal marrows. The patient recovered fully after therapy with antithymocyte globulin and marrow cultures showed disappearance of the inhibitory effect. These observations suggest that the severe aplasia may have resulted from an aberrant immune response which followed infection by EB virus. 相似文献