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Human platelets exert cytotoxic effects on tumor cells   总被引:6,自引:0,他引:6  
Ibele  GM; Kay  NE; Johnson  GJ; Jacob  HS 《Blood》1985,65(5):1252-1255
Monocytes are thought to play a role in host resistance to tumor cell growth in animals and humans. In addition, platelets are known to be involved in tumor metastases. To investigate the interaction of these two cell types and their effect on tumor cells, human monocytes and platelets were examined using an in vitro monocyte-tumor cell cytotoxicity assay. Monocytes alone resulted in 32% +/- 1.5 (mean +/- SEM) tumor cell kill. When platelets were added to monocytes in a 1:1 ratio, an increase in cytotoxicity to 61% +/- 3.2 was observed. The cytotoxicity noted when platelets were added to a fixed number of monocytes and tumor cells was dependent on the number of platelets added. A decrease in cytotoxicity from 32% +/- 1.5 to 12% +/- 2.3 was observed when contaminating platelets were removed from monocyte preparations. Platelets added to tumor cells in the absence of any monocytes were also toxic, resulting in a maximum kill of 95% at a 4:1 platelet/tumor cell ratio. Secreted products of freshly isolated platelets may be responsible for much of the observed cytotoxicity, since supernatants from the platelets were toxic for tumor cells. Platelets pretreated with a cyclooxygenase inhibitor (ASA) or a lipoxygenase inhibitor had decreased cytotoxicity compared with untreated platelets. Our results indicate that products of platelet arachidonate metabolism are toxic for tumor cell lines. They also suggest that the role of the platelet must be considered when studying monocyte-tumor cell cytotoxicity.  相似文献   
44.
Charache  S; Dover  GJ; Moyer  MA; Moore  JW 《Blood》1987,69(1):109-116
Five patients with sickle cell anemia were treated with hydroxyurea (HU), in hopes of augmenting their production of fetal hemoglobin. Laboratory responses in two patients treated for more than 2 years were encouraging and there were suggestions of clinical improvement. Long- term HU therapy should be considered for severely affected adults with sickle cell anemia who are willing to accept what is probably a small risk of carcinogenesis. Preliminary chromosomal analysis and knowledge of the clastogenic properties of HU suggest that conception and pregnancy should be avoided. Pharmacokinetic studies will probably be necessary to adjust individual dosage schedules so that cytotoxicity is avoided. F cell responses can be seen in 2 to 3 weeks if the HU dose is optimal, but establishment of a large number of F cells in the circulation may take a month or longer.  相似文献   
45.
2010年8月,美国心脏病学会基金会(ACCF)、美国心脏学会(AHA)共同发布了美国食品药品管理局(FDA)关于氯吡格雷的"盒装警告",主要针对医师和患者提出建议,其内容包括:通过检测药物基因型以明确患者氯吡格雷的代谢变化,患者不良反应的风险,基因多态性对氯吡格雷的代谢及临床影响。  相似文献   
46.
In this article, we describe a relatively simple surgical option that we believe is indicated for use in cases of cervical incompetence. We discuss the advantages of this procedure to the surgeon and patient, and give details of 59 patients who have undergone this procedure one or more times over a 13-year period. A short review of the history of treatment of cervical incompetence and of recent trends for its management is also presented.  相似文献   
47.
We measured red blood cell iron incorporation (RBC-inc) in 13 human milk-fed premature infants (birthweight 1037 +/- 289 g, gestational age 27 +/- 2 wk, weight at start of study 1571 +/- 426 g) who were receiving full tube-feedings of human milk fortified with a commercial human milk fortifier (FortHM). The relative RBC-inc of supplemental iron (2 mg/kg/d of ferrous sulfate) was assessed using 57Fe sulfate mixed directly into a 24-h volume of FortHM, and 54Fe sulfate given as a bolus between two FortHM feedings the next day. RBC-inc was similar between the two methods of supplemental iron administration (4.7 +/- 2.5% vs 4.6 +/- 1.5%, respectively). Although these values are lower than RBC-inc expected from iron native to human milk, the relatively large amount of iron in the supplements contributed most of the iron incorporated into RBC by the infants. There was a significant positive correlation between the reticulocyte count and RBC-inc. As the high nutrient (especially calcium) content of the FortHM did not interfere with iron utilization, adding iron directly to FortHM, or incorporating it into commercial fortifiers, may be a practical method to provide iron to premature infants.  相似文献   
48.
Surgery remains the treatment of choice for massive and recurrent hemoptysis. In some instances, however, immediate surgical intervention is contraindicated. In these situations, bronchial artery embolization (BAE) has proved to be a successful definitive treatment for non-surgical candidates and a palliative therapy in patients requiring hemodynamic stabilization prior to surgery. The most serious complication of BAE is spinal cord ischemia. This relates directly to the potential anastomotic connections between the bronchial circulation and the anterior spinal artery. Somatosensory evoked potentials (SSEPs) have been used in the past to monitor spinal cord ischemia during procedures that threaten the vascularity of the spinal cord. The authors report two cases in which SSEPs were employed to monitor spinal cord ischemia during bronchial artery embolization.  相似文献   
49.
目的:采用定量分析方法比较体育与非体育专业大学生静态平衡能力,分析运动及性别对大学生静态平衡功能的影响。方法:于2007-01/03选取首都体育学院在校大学生共78名为受试对象,其中体育(武术)专业学生40名,非体育(康复)专业学生38名。所有选取对象了解试验目的,并同意参与本实验。采用意大利PosturalEqua平静分析系统,对实验对象分别在睁眼60s、闭眼60s两种状态下测试其静态平衡的各项指标,包括压力中心,线形图总长度,最大摆幅,线形图面积,LFS指数,压力分布,稳定性图及隆伯格值。结果:78名为受试对象均进入结果分析。①两专业学生压力中心X轴短于Y轴、压力分布前(%)高于后(%)(P<0.01)。②在闭眼状态下,体育专业男大学生在指标LFS指数和额状面上大于非体育专业(P<0.05)。③非体育业大学生在睁眼状态下,Y值女性小于男性,额状面值女性大于男性。男、女生睁闭眼差值进行比较时,女性在线形图总长度、额状面和LFT指数均大于男性(P<0.01),而线形图面积小于男性(P<0.05)。④体育专业大学生在睁眼状态下,指标参数Y值女性小于男性,额状面值女性大于男性;闭眼状态下,指标参数Y值女性小于男性,额状面值和LFS值女性大于男性。男、女生睁闭眼差值比较,女性在线形图总长度、额状面和LFT指数均大于男性(P<0.05,P<0.01),而线形图面积小于男性(P<0.05)。结论:①运动训练对大学生静态平衡影响不大,但对男性大学生的某些平衡指标却有显著影响。②性别对大学生的静态平衡均产生影响,表现为男性平衡的微控制能力优于女性。  相似文献   
50.
目的:观察胸段硬膜外复合全静脉麻醉和全静脉麻醉对单、双肺通气能量代谢、呼吸氧价和应激反应的影响,比较两者的差异。方法:选择2004-07/2005-01徐州医学院附属医院心胸外科择期行食管癌根治术且需要单肺通气的患者40例,按随机数字表法分为硬膜外复合全静脉麻醉组(n=20)和全静脉麻醉组(n=20),经患者同意并签字后进入试验。分别在单肺通气和双肺通气时进行氧耗量、二氧化碳排出量、能量代谢和呼吸商测定,同时测量肾上腺素、去甲肾上腺素、皮质醇和血糖水平。结果:40例患者全部进入结果分析,无脱落。①在单、双肺通气时硬膜外复合全静脉麻醉组的氧耗量、二氧化碳排出量、能量代谢均高于全静脉麻醉组(P<0.05);两组患者单肺通气时段氧耗量、二氧化碳排出量、能量代谢低于双肺通气时段,但差异无显著性意义(P>0.05)。②在单、双肺通气时硬膜外复合全静脉麻醉组的肾上腺素、去甲肾上腺素、皮质醇和血糖水平均低于全静脉麻醉组(P<0.05);单、双肺通气相比,两组患者肾上腺素、去甲肾上腺素变化差异无显著性意义(P>0.05)。结论:与全静脉麻醉相比,胸段硬膜外阻滞复合全静脉麻醉能够增加胸科手术的氧耗量、能量代谢,减轻应激反应。单、双肺通气期间没有明显差异。  相似文献   
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