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91.
92.
We compared the ability of recombinant human tumor necrosis factor- alpha (rHuTNF-alpha) and tumor necrosis factor-beta (rHuTNF-beta) to stimulate polymorphonuclear neutrophil (PMN) migration and superoxide production. Significant PMN migration occurred across polycarbonate filters after stimulation with rHuTNF-alpha at concentrations ranging from 10(-7) to 10(-10) mol/L and at 10(-7) to 10(-8) mol/L for rHuTNF- beta and N-formylmethionyl-leucyl phenylalanine (FMLP), whereas recombinant human interferon-gamma was only minimally active at 10(-7) mol/L and recombinant human interleukin-1 alpha was inactive at the doses tested. In addition, antibodies to rHuTNF-alpha completely inhibited rHuTNF-alpha but not rHuTNF-beta or FMLP-induced PMN migration. Combinations of rHuTNF-alpha and rHuTNF-beta (at similar molar concentrations) stimulated PMN migration levels comparable to that obtained with rHuTNF-alpha alone. Checkerboard analyses performed by placing different concentrations of rHuTNF-alpha and rHuTNF-beta above and below polycarbonate filters of microchemotaxis chambers demonstrated that rHuTNF-alpha and rHuTNF-beta stimulated both chemotactic and chemokinetic responses by PMN. Additional studies demonstrated that 1 X 10(-8) mol/L rHuTNF-alpha and 3 X 10(-9) mol/L rHuTNF-beta (which represents 10(4) U/mL of each cytokine) were similar in their ability to induce superoxide production by PMNs; however, at ten- to 100-fold lower molar concentrations (10(3) and 10(2) units), rHuTNF-alpha was significantly more active than rHuTNF-beta. At the doses tested, both cytokines were less active than phorbol myristate acetate at stimulating O2- release. The results demonstrate that rHuTNF- alpha and rHuTNF-beta differ quantitatively but not qualitatively in their effects on PMN functions in vitro and suggest that rHuTNF-beta may be less toxic than rHuTNF-alpha in vivo. 相似文献
93.
目的:探讨美托洛尔缓释片治疗原发性高血压(EH)并舒张压性心力衰竭(DHF)患者的临床疗效。方法:选取2010年7月-2013年4月本院就诊的126例EH合并DHF患者作为研究对象,所有患者给予美托洛尔缓释片治疗12个月。分别观察治疗前后患者的血压、心率、VEGF和hs-CRP水平的变化,同时观察心脏结构、左室功能参数变化及心功能分级的变化情况。结果:治疗后,左室舒张末径(LVEDD)和左室收缩末径(LVESD)显著减小,二尖瓣返流现象显著减轻,左室射血分数(LVEF)、左室高峰充盈数(LVPFR)显著增加,收缩压、舒张压、脉压和心率以及VEGF和hs-CRP、N末端钠肽原(NT-proBNP)均显著降低,上述指标治疗前后比较差异均具有统计学意义(P<0.05)。结论:美托洛尔缓释片治疗EH并DHF患者,能显著改善患者的心脏功能,治疗效果显著,值得在临床上进一步推广。 相似文献
94.
目的 调查成人阻塞性睡眠呼吸暂停低通气综合征(OSAHS)患者的人格特征及生活质量,了解该患病群体的心理健康情况。方法 采用明尼苏达多项人格测量表(Minnesota multiphasic personality inventory,MMPI)和简明健康状况调查表(the MOS item short from health survey,SF-36)分别对98例成人OSAHS患者及100例单纯鼾症志愿者进行问卷调查,评价OSAHS患者的人格特征及生活质量情况并进行对照性研究。结果 在MMPI调查中,OSAHS患者在抑郁、疑病、精神衰弱、情绪不稳定、精神分裂临床量表T分高于单纯鼾症组,差异具有统计学意义(P<0.05),其中OSAHS组中女性患者的抑郁、疑病、精神衰弱、情绪不稳定、精神分裂、社会内向临床量表T分高于男性患者,差异具有统计学意义(P <0.05)。在SF-36调查中,OSAHS患者在生理职能、一般健康状况、躯体疼痛、精力、社会功能、情感功能、精神健康7个维度的平均评分低于单纯鼾症组,差异具有统计学意义(P<0.05)。结论 OSAHS患者有较多的心理健康问题,表现更多的易疲劳、注意缺陷,生活质量更低,OSAHS病情越重,心理健康问题越大,女性患者尤重。 相似文献
95.
小肠是消化道中最长的一段,是食物消化、吸收和能量转化的主要场所,但小肠肿瘤的相关研究却鲜有报道。原发性小肠恶性肿瘤在临床少见,由于缺乏典型临床表现及有效治疗手段,导致预后极差。小肠巨大的表面积及上皮快速更新的状态与小肠肿瘤的低发病率显然相悖。小肠肿瘤较低的发病率这一科学问题已成为困扰医学科学领域的世纪之谜。本综述主要从小肠独特的生理屏障、基因调控系统、共生菌群及黏膜免疫系统四个方面剖析小肠肿瘤罕见的原因。理解小肠精密的调控机制将为研究衰老、肠道菌群及肿瘤防治提供新思路。本文基于以往研究,结合最新进展对小肠肿瘤流行病学现状、低发病率的可能原因及其对肿瘤防治的启示进行综述。 相似文献
96.
Cirrhosis is frequently associated with increased arterial plasma renin activity. This could be the result of increased renin production or diminished renin clearance. We measured plasma renin activity in simultaneous portal, hepatic vein, and femoral artery blood samples in 7 patients with clinically stable alcoholic cirrhosis to determine whether hepatic extraction of renin is reduced and whether, as has been suggested, there is a splanchnic source of plasma renin activity in this condition. Plasma renin activity (mean +/- S.E. in ng/ml/min) was similar in portal, arterial, and hepatic venous samples (portal: 8.0 +/- 3.7; arterial: 7.6 +/- 3.1; hepatic vein: 6.4 +/- 2.3). Hepatic extraction of plasma renin activity, calculated as [arterial-hepatic vein)/arterial) X 100, was 14 +/- 6%, not significantly different from reported normal values (26 +/- 3%, n = 46). The intrinsic hepatic clearance of plasma renin activity (235 +/- 89 ml/min) and the hepatic renin extraction rate (1.801 +/- 1.032 micrograms/min) were also similar to estimated normal values. The intrinsic clearance and extraction rates of renin correlated with arterial plasma renin activity (r = 0.93, P less than 0.01 and r = 0.79, P less than 0.05). These data indicate that in clinically stable patients with alcoholic cirrhosis: (1) hepatic renin clearance is not significantly impaired; and (2) there is not a splanchnic source of plasma renin activity. Therefore, increased peripheral plasma renin activity in this condition is due solely to increased renal renin production. 相似文献
97.
B-cell growth factor receptor expression and B-cell growth factor response of leukemic B cell precursors and B lineage lymphoid progenitor cells 总被引:8,自引:1,他引:8
Uckun FM; Fauci AS; Heerema NA; Song CW; Mehta SR; Gajl-Peczalska K; Chandan M; Ambrus JL 《Blood》1987,70(4):1020-1034
The purpose of this study was to analyze the expression of B cell growth factor (BCGF) receptors and to elucidate the biologic effects of biochemically purified natural BCGF at the B cell precursor stage of human B lineage lymphoid differentiation. The specific binding of radioiodinated high-mol-wt BCGF (125I-HMW-BCGF) and low-molecular-wt BCGF (125I-LMW-BCGF) to fresh marrow blasts from B cell precursor acute lymphoblastic leukemia (ALL) patients was initially investigated. The estimated number of radioiodinated BCGF molecules bound per blast ranged from undetectable to 24.3 X 10(3) for HMW-BCGF, and from 11.5 X 10(3) to 457.8 X 10(3) for LMW-BCGF. In 3H-TdR incorporation assays, 75% of cases showed a significant response to LMW-BCGF with a median stimulation index of 9.3. By comparison, only 33% of cases showed a significant response to HMW-BCGF with a median stimulation index of 2.4. Subsequently, B cell precursor colony assays were performed to assess and compare the biologic effects of BCGF on leukemic B lineage lymphoid progenitor cells. Among 28 cases studied, 57% responded to both HMW-BCGF and LMW-BCGF, 21% responded only to LMW-BCGF, and the remaining cases showed no proliferative response to either growth factor. The response patterns of virtually pure populations of FACS- sorted leukemic B cell precursors were essentially identical to the proliferative responses of unsorted leukemic B-cell precursors. Synergistic effects between HMW-BCGF and LMW-BCGF were observed in 80% of the cases that responded to both. The numbers of cell-bound radioiodinated BCGF molecules, the stimulation indices, as well as the number of B cell precursor colonies in BCGF-stimulated cultures showed a marked interpatient variation. Patients with structural chromosomal abnormalities (SCAs) involving 12p11-13 or patients with a Philadelphia chromosome showed a greater HMW-BCGF response at the level of leukemic progenitor cells than did other patients (P = .02). The LMW-BCGF response was significantly greater for patients with SCA than for patients without SCA (P = .04). The response of leukemic progenitor cells to HMW-BCGF or LMW-BCGF did not correlate with sex, age, disease status, FAB morphology, WBC at diagnosis, or immunophenotype. To our knowledge, this study represents the first detailed analyses of BCGF receptor expression and BCGF effects in B cell precursor ALL. The data presented provide direct evidence for the expression of functional receptors for both HMW-BCGF and LMW-BCGF in B cell precursor ALL. 相似文献
98.
99.
目的 分析新疆维吾尔族(维族)IFG人群血脂代谢状况及LDL-C升高的危险因素。 方法 对新疆地区2053例30~80岁维族居民行横断面调查,筛查IFG人群,分析血脂代谢状况及LDL-C相关危险因素。 结果 该IFG人群中,血脂代谢异常的总患病率为99.8%(613/614)。高TG血症患病率为85.5%(525/614),男女比较,差异无统计学意义(P〉0.05);高TC血症、高LDL-C血症患病率为72.5%(445/614)和40.7%(250/614),男性高于女性(75.0% vs 70.1%,52.4% vs 29.9%,P〈0.05);低HDL-C血症患病率为29.8%(183/614),男性低于女性(28.0% vs 31.4%,P〈0.05)。Logistic回归分析显示,LDL-C升高的危险因素为年龄、TC、2 hPG。 结论 维族IFG人群血脂代谢异常的总患病为99.8%,其中LDL-C升高的患病率为40.7%,其危险因素为年龄、TC和2 hPG。 相似文献
100.
目的: 通过建立人肠道病毒71型(EV71)感染在免疫抑制恒河猴的动物模型,进一步分析人EV71在免疫抑制动物体内病毒增殖、病理变化以及病毒抗原在不同组织的表达情况。方法: 按照每天15 mg/kg的剂量给8只恒河猴口服环孢菌素A连续7 d后造成其免疫抑制状态,再经呼吸道和消化道感染EV71病毒FY23株,对其进行14 d的临床观察后处死,采集各器官组织进行病毒载量检测,同时对不同的组织进行病理学分析和免疫组化分析。结果: 感染EV71病毒后,免疫抑制组的临床症状、病毒载量、病理分析和免疫组化结果都明显比非免疫抑制组严重,从病毒对机体造成的影响来看呼吸系统感染较消化系统感染明显严重。结论: 本实验分析了人EV71在免疫抑制动物体内病毒增殖的情况,为建立用于EV71疫苗评价的恒河猴动物模型提供了依据,并对未来的EV71疫苗的使用人群范围做出了新的限定。 相似文献