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41.
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Human natural killer (NK) cells are large granular lymphocytes that constitutively express functional forms of the interleukin-2 receptor (IL-2R) and lyse tumor and virally infected cells without prior sensitization. NK cells with high density expression of CD56 (CD56bright) express the high affinity IL-2R and proliferate in response to low (picomolar) concentrations of IL-2. CD56dim NK cells express the intermediate affinity IL-2R and demonstrate enhanced cytotoxic activity without proliferation in response to high (nanomolar) concentrations of IL-2. In the present study, we characterized IL-10R expression on human NK cells and the functional consequences of IL-10 binding directly to highly purified subsets of CD56bright and CD56dim NK cells. Binding studies using 125I-IL-10 indicated that resting human NK cells constitutively express the IL-10 receptor protein at a surface density of approximately 90 receptor sites per cell, with a kd of approximately 1 nmol/L. Alone, IL-10 did not induce proliferation of CD56bright or CD56dim NK cell subsets. However, at low concentrations (0.5 to 5 ng/mL), IL-10 significantly augmented IL-2-induced proliferation of the CD56bright NK cell subset mediated via the high-affinity IL-2R. In the absence of IL-2, IL-10 was able to induce significant NK cytotoxic activity against NK-resistant tumor cell targets in both subsets of NK cells in a dose-dependent fashion. Furthermore, the combination of IL-10 and IL-2 had an additive effect on NK cytotoxic activity, whereas that of IL-10 and IL-12 did not. Production of interferon-gamma, tumor necrosis factor-alpha, and granulocyte-macrophage colony-stimulating factor by IL-2-activated NK cells was also significantly enhanced by IL-10. Neither resting nor activated human NK cells appear to produce human IL-10 protein. In summary, NK cells constitutively express the IL-10R protein in low density, and the functional consequences of IL-10 binding directly to human NK cell subsets appear to be stimulatory and dose-dependent. In contrast to its direct effects on human T cells and monocytes/macrophages, IL-10 potentiates cytokine production by human NK cells.  相似文献   
43.
Reports of smoking cessation studies often claim that many relapsed subjects reduce their smoking. We investigated the smoking habits of relapsers 1 year after quitting in a smoking cessation trial using nicotine or placebo patches. All 289 participants in that study were summoned to a 1-year follow-up visit–148 (57%) of 259 relapsers attended, as did all 30 sustained abstainers. Fewer than 1% of the subjects had quit spontaneously after the primary relapse. Daily cigarette consumption, standard nicotine yield per cigarette, saliva cotinine concentration, expired carbon monoxide level and two nicotine dependency scales were assessed at entry and at the 1-year follow-up. In five of these six smoking-related characteristics, there was a small but significant mean reduction of 7%-27%. A significant weight gain of 0.5 ± 2.9 kg (mean ± SD) was recorded in the relapsers compared with 4.8 ± 4.2 kg for abstainers (p < 0.001). It is concluded that smoking habits in relapsers are relatively unchanged, and thus the most important outcome measure in smoking cessation trials is abstinent subjects.  相似文献   
44.
目的:通过对喉癌患者未被癌组织侵及的喉内肌及正常人的喉内肌肌纤维形态、结构的比较分析,从组织学角度揭示二者之间的差异。方法:将5例喉癌患者未被癌组织侵及的肌纤维和1例使康成人的甲杓肌、环杓侧肌及环杓后肌经HE染色,于镜下观察肌纤维的形态,并采用显微图像分析仪测量肌纤维的横截面积和最大宽度。结果:喉癌患者与使康成人相比,各喉内肌肌纤维形态差异较大;肌纤维横截面积、最大宽度有显著增加(P<0.01),增加的幅度均为环杓后肌>环杓侧肌>甲杓肌。结论:喉癌患者未被癌组织侵及的肌纤维不仅在形态上有很大的不同,而且肌纤维横截面积及最大宽度明显增大,可能是癌变增加了呼吸道的阻力,各喉内肌代偿性活动的结果。  相似文献   
45.
Rotator cuff: evaluation with fat-suppressed MR arthrography   总被引:11,自引:0,他引:11  
Palmer  WE; Brown  JH; Rosenthal  DI 《Radiology》1993,188(3):683
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46.
Kayexalate: a new cause of neonatal bowel opacification   总被引:1,自引:0,他引:1  
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47.
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49.
Gastric angiodysplasia   总被引:1,自引:0,他引:1  
Roberts  LK; Gold  RE; Routt  WE 《Radiology》1981,139(2):355
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50.
A method of combined cataract extraction with posterior chamber intraocular lens and trabeculectomy using separate incisions was tested in 44 operations on 38 patients. The mean preoperative intraocular pressure (IOP) of 28.1 ± 11.7 (range 12 to 56) mmHg on maximum medication was lowered to 13.9 ± 3.4 (9 to 23) mmHg at one year, with half the eyes still requiring topical medication. The IOP was 40 mmHg or more preoperatively in eight eyes and 20 mmHg or more in only two patients at one year. There were no rises in IOP above 20 mmHg in the early postoperative period (days 1 and 2). Visual acuity was 6/9 or better in 27 and 6/12 in three eyes. There was an expulsive haemorrhage in one case, rupture of the posterior capsule in two eyes and a choroidal detachment in one eye, but no flat anterior chambers. The two-incision method allowed placement of an intraocular lens with good postoperative pressure control.  相似文献   
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