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71.
72.
Interleukin-11 stimulates multilineage progenitors, but not stem cells, in murine and human long-term marrow cultures 总被引:3,自引:0,他引:3
Interleukin-11 (IL-11) is a bone marrow microenvironment-derived growth factor with pleiotropic effects on a variety of hematopoietic cells. To more accurately assess the effects of IL-11 on stem and progenitor compartments within the hematopoietic microenvironment (HM), we added recombinant human (rh) IL-11 to human and murine long-term bone marrow cultures (LTMC) and analyzed primitive (high proliferative potential- colony forming cells [HPP-CFC], long-term culture-initiating cells [LTC- IC], and long-term reconstituting stem cells) and progenitor (day 12 colony forming unit-spleen [CFU-S12], colony forming unit-megakaryocyte [CFU-Mk] and colony forming unit-granulocyte/macrophage [CFU-GM]) compartments throughout the duration of the cultures. rhIL-11 (100 ng/mL) added twice weekly resulted in significantly increased nonadherent (NA) cellularity, CFU-GM, and CFU-Mk production in human LTMC. Addition of rhIL-11 to murine LTMC was associated with a 5- to 40- fold increase in CFU-GM and a four- to 20-fold increase in day 12 CFU-S in NA cells. However, IL-11 had no significant effect on total HPP-CFC concentration and decreased the size of the more primitive stem/progenitor compartment as evidenced by both decreased LTC-IC frequency in human LTMC and decreased frequency of long-term reconstituting stem cells in murine LTMC. These data suggest that IL-11 may increase commitment of stem cells into a multipotential progenitor compartment. 相似文献
73.
Acquired immune hemolytic anemia associated with IgA erythrocyte coating: investigation of hemolytic mechanisms 总被引:1,自引:0,他引:1
We have investigated the hemolytic mechanisms in a patient with acquired immune hemolytic anemia whose red cells appeared to be coated with IgA alone. The clinical course was similar to that of patients with hemolytic anemia mediated by warm-reacting IgG antibody. Splenic sequestration of red cells was demonstrated, and marked reduction of hemolysis occurred after corticosteroid therapy. Antibody was eluted from the patient's red cells and used to sensitize normal red cells in vitro. These sensitized red cells were not lysed by fresh autologous serum, nor did they fix detectable amounts of C3. However, red cells sensitized by eluted antibody were lysed by normal human peripheral blood monocytes in a system designed to demonstrate antibody-dependent cell-mediated cytotoxicity. Monocyte-mediated hemolysis of sensitized red cells was inhibited by the addition of low concentrations of normal serum IgA to the system, but not by IgG. The ability of the eluate to induce monocyte-mediated hemolysis was abolished by its adsorption on Sepharose-bound anti-IgA, but not by preincubation with Sepharose-bound anti-IgG. In addition, normal human monocytes were demonstrated to ingest eluate-sensitized red cells. These data demonstrate an in vitro interaction of IgA-sensitized red cells with leukocytes and suggest a possible mechanism for the patient's hemolysis. 相似文献
74.
目的对比高黏度与低黏度骨水泥经皮椎体后凸成形术(PKP)治疗骨质疏松性椎体压缩性骨折(OVCF)的疗效差异。方法将2013年3月至2014年9月高要市人民医院收治的60例OVCF患者采用随机抽签法分为低黏度组(低黏度骨水泥PKP治疗)和高黏度组(高黏度骨水泥PKP治疗),每组各30例。对比两组手术前后伤椎椎体高度和后凸Cobb角;采用视觉模拟量表(VAS)评分、Oswestry功能障碍指数(ODI)、36项健康调查简表(SF-36)评分对患者疼痛程度、功能障碍和生活质量等主观感受进行评价;统计骨水泥渗漏、近期肺栓塞等并发症发生情况。结果低黏度组和高黏度组骨水泥注入量分别为(3.1±0.6)m L和(3.6±0.8)m L,两组比较,差异有统计学意义(P0.05)。术后随访3~6个月(平均4个月),两组术后1 d、3个月VAS评分、ODI、SF-36评分、伤椎椎体高度和后凸Cobb角均优于术前(P0.05),其中高黏度组术后1 d、3个月上述指标均优于低黏度组(P0.05)。低黏度组和高黏度组术后发生骨水泥渗漏、近期肺栓塞分别为6、2例和1、0例,两组并发症发生率比较,差异有统计学意义(P0.05)。结论与低黏度骨水泥比较,高黏度骨水泥PKP治疗OVCF近期疗效更为理想,骨水泥渗漏、近期肺栓塞等并发症发生率相对较低,值得临床推广应用。 相似文献
75.
目的 探讨改良颈腮腺入路在高位咽旁间隙良性肿瘤手术中的应用疗效。 方法 7例咽旁间隙良性肿瘤患者,术前影像学检查提示为高位、肿瘤巨大、哑铃型且边界欠清,采用改良颈腮腺入路术式,解剖辨认面神经总干及颞面干后,于外耳道软骨前方、腮腺的后缘以及颞面干的上方间隙向深部分离至肿瘤上极,剥离子分离并下压肿瘤与下方常规颈部自下而上肿瘤游离会师后,从颌下区取出肿瘤。腮腺浅叶不切除,面神经分支不做过多解剖。 结果 所有患者均一次性完整切除肿瘤;术后病理示多形性腺瘤6例,神经鞘瘤1例;术中出血均少于300 mL;1例患者出现术后同侧眼睑轻度闭合障碍,两周后完全正常;所有患者面容美学保存理想。 结论 对于高位咽旁间隙良性肿瘤采用改良颈腮腺入路术式,不仅可以安全完整地切除肿瘤,同时由于减少了面神经及腮腺浅叶的处置,术后相关神经并发症及腮腺区凹陷性改变的发生率下降。 相似文献
76.
L. Grönholm K. K. Lemberg L. Tjäderhane A. Lauhio C. Lindqvist R. Rautemaa-Richardson 《Clinical oral investigations》2013,17(1):113-121
Objectives
The aim of this study was to evaluate clinical and radiological findings and the role of periapical infection and antecedent dental treatment of infected focus teeth in odontogenic maxillofacial abscesses requiring hospital care.Materials and methods
In this retrospective cohort study, we evaluated medical records and panoramic radiographs during the hospital stay of patients (n?=?60) admitted due to odontogenic maxillofacial infection originating from periapical periodontitis.Results
Twenty-three (38 %) patients had received endodontic treatment and ten (17 %) other acute dental treatment. Twenty-seven (45 %) had not visited the dentist in the near past. Median age of the patients was 45 (range 20–88) years and 60 % were males. Unfinished root canal treatment (RCT) was the major risk factor for hospitalisation in 16 (27 %) of the 60 cases (p?=?.0065). Completed RCT was the source only in 7 (12 %) of the 60 cases. Two of these RCTs were adequate and five inadequate.Conclusions
The initiation of inadequate or incomplete primary RCT of acute periapical periodontitis appears to open a risk window for locally invasive spread of infection with local abscess formation and systemic symptoms. Thereafter, the quality of the completed RCT appears to have minor impact. However, a considerable proportion of the patients had not received any dental treatment confirming the importance of good dental health. Thus, thorough canal debridement during the first session is essential for minimising the risk for spread of infection in addition to incision and drainage of the abscess. If this cannot be achieved, tooth extraction should be considered.Clinical relevance
Incomplete or inadequate canal debridement and drainage of the abscess may increase the risk for spread of endodontic infection. 相似文献77.
AP Mishreki E Lim P Cranefield S Pascoe S Jackson DA Stell 《Annals of the Royal College of Surgeons of England》2013,95(5):349-352
Introduction
The results of surgical resection and palliative chemotherapy use in hilar cholangiocarcinoma (HC) have been well publicised but the proportion of patients able to undergo these treatments and the comparative outcomes in a population of patients with HC are less well known.Methods
Patients with HC were identified by review of all patients undergoing percutaneous cholangiography over a nine-year period (2002–2010) in a tertiary facility. The treatment undertaken and outcomes were recorded.Results
Overall, 68 patients were identified (37 female) with a median age of 70 years. Forty-five (66%) were treated solely by insertion of a metal stent (median survival 4.73 months) and nine (13%) also received palliative chemotherapy (median survival 13.7 months). Persisting jaundice after stent insertion was noted in 18 of 35 patients (51%) tested within one month of death. Fourteen patients (21%) underwent surgical resection (median survival 20.2 months).Conclusions
Patients undergoing surgical resection had significantly longer survival than those receiving only a palliative stent but not compared with those also receiving palliative chemotherapy, with short-term follow-up. Only a third of patients, however, receive active treatment (surgery or chemotherapy) and improvements in long-term biliary palliation are needed. 相似文献78.
Crohn's disease is an increasingly global health concern. Currently without a cure, it significantly alters the quality of life of Crohn's disease sufferers and places a heavy financial burden on the community. Recent reports show that the rising prevalence of Crohn's disease is no longer confined to Western countries, with considerable increases seen particularly in Asia. Nutritional problems are often associated with Crohn's disease, most notably in the paediatric population, with underweight and stunting commonly seen at presentation. In addition, linear growth retardation and pubertal delay can also manifest in these younger patients. Therefore, exclusive enteral nutrition has been used as a therapeutic option to treat Crohn's disease, in part to address the nutritional complications of the disease. Exclusive enteral nutrition can improve nutrition as well as induce remission at a rate equivalent to corticosteroids. It is safe particularly with long-term use and can induce mucosal healing, considered the gold standard for therapy, at a rate superior to corticosteroids. Exclusive enteral nutrition has thus become the preferred therapeutic option in many centres for the treatment of paediatric Crohn's disease. This review discusses the role of exclusive enteral nutrition as a therapeutic option for the treatment of Crohn's disease, as well as the latest findings into its mechanisms of action. 相似文献
79.
目的评价腹膜外切口单层缝合与常规分层缝合法在化脓性或坏疽性阑尾炎术后的临床疗效。方法计算机检索Co-chrane Library、PubMed、Embase、SCI、CNKI、CBM、VIP、WANFANG DATA,纳入腹膜外切口单层缝合与常规分层缝合法在化脓性或坏疽性阑尾炎术后疗效比较的随机对照试验,对纳入研究的方法学质量进行评价,用Cochrane协作网提供的RevMan 5.1软件对数据进行统计分析,并对统计结果进行系统评价。结果共纳入6个随机对照试验,共计1 885例患者。Meta分析结果显示:腹膜外切口单层缝合与常规分层缝合法在手术时间[MD=-17.09,95%CI(-19.32,-14.87)],术后切口感染率[RR=0.06,95%CI(0.03,0.12)],7 d内出院率[RR=1.17,95%CI(1.13,1.22)]方面差异均具有统计学意义,但两者在术后疼痛程度(需应用镇痛药物比率)[RR=1.05,95%CI(0.91,1.20)]方面的差异无统计学意义。结论目前研究表明,与常规分层缝合法相比,腹膜外切口单层缝合法能显著缩短化脓性或坏疽性阑尾炎患者的手术时间,降低术后切口感染率,提高7 d内出院率,但本研究纳入的样本量小且质量不高,因此,有必要开展更多高质量、多中心的随机盲法对照试验进一步予以证实其疗效。 相似文献
80.
目的:探讨不同呼吸机湿化管道系统在老年机械通气患者中的应用效果。方法:选取老年机械通气患者140例,随机分为3组,其中A组(n=43)使用MR410型湿化管道系统,B组(n=47)使用MR730型湿化管道系统,C组(n=50)采用MR 850型一次性双加热式、自动加水加湿湿化管道系统。观察3组湿化效果、并发症发生情况、通气时间及管道护理情况。结果:C组湿化效果适中比例最高,其次为B组,A组最低,3组间差异有统计学意义(P<0.01)。C组无导管痰痂和气道痉挛的发生,A组发生率最高,3组间差异有统计学意义(P<0.01)。C组通气时间、管道总更换次数、呼吸机管道护理时数均低于A、B组,差异有统计学意义(P<0.01)。结论:使用MR850型一次性双加热式、自动加水加湿湿化管道系统湿化效果最好,能降低并发症发生率,缩短通气时间和护理工作量。 相似文献