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61.
Lymphokine-activated killer (LAK) cells were induced with low-dose recombinant interleukin 2 (rIL-2) and recombinant interferon- (IFN-) in 28 oral carcinoma patients. The patients received daily intravenous injections of rIL-2 (1.2×105 U/m2) and rIFN- (7.0×104 U/m2), and both natural killer (NK) and LAK activities were periodically examined. A significant increase in CD16+CD57+ and CD16+CD57 NK subsets was observed after the induction. An increase in the T-cell population was also found, with a significant increase in CD3+HLA-DR+, CD8+Leu8, and CD4+Leu8 cells. Significant increases in NK activity, from the original level of 32.0±13.7 to 49.9±15.2%, and LAK activity, from 4.8±3.5 to 11.0±6.1%, at Day 7 were observed. Both activities were maintained at high levels during the cytokine injections, but greater enhancement of the killing activities could not be obtained subsequently. When NK and LAK activities were investigated in each subpopulation of CD3 and CD16 cells, no remarkable cytotoxic activity could be observed before induction in any subset without NK activity in CD3 cells (31.1±14.3%). At Day 7, NK activity of CD16 cells increased up to 21.4±14.9%, accompanied by an increase in CD3-cell activity (54.5±20.6%). LAK activities of both subsets were also enhanced, with activity at Day 7 of 6.5±5.6 and 9.4±6.6% in CD16 and CD3 cells, respectively. These increased activities were maintained at the same level during the induction. Phorbol myristate acetate-induced polymorphonuclear leukocyte (PMNL) O 2 generation was significantly increased, from the original 81.1±28.1 to 95.6±34.9 pmol/min/104 cells, after 1 week of treatment. Protein kinase C activity in the cytosol decreased, and the activity in the membrane fraction conversely increased. No remarkable adverse effects except for mild fever were observed. Together with LAK induction ability and PMNL enhancement, with scarce toxicity, a combination of low-dose rIL-2 and rIFN- is thought to be useful in cancer treatments.  相似文献   
62.
The effects of two kinds of induction speed of sevoflurane anesthesia on the EEG pattern were compared in the same individual using medical student volunteers: a first exposure of 4% was given, followed after full recovery, by incremental doses of 1, 2 and 4% successively, each being administered for 10min. The arterial blood level of the anesthetic was measured using gaschromatograph. The changes of EEG pattern during fast induction with 4% were not represented by the abbreviation of those observed during the slow induction with the incremental doses. The administration of 4% induced a sudden appearance of high voltage, rhythmic slow waves of 2–3Hz at 1–3min when the arterial blood anesthetic level increased maximally, which was then followed by a pattern of faster activities of 10–14Hz mixed with 5–8Hz slow waves. In contrast, the administration of incremental doses induced an increase in frequency and amplitude of EEG activities in the light plane, followed by their decreases in deeper planes. The final EEG patterns were identical for both these methods of induction. These findings confirmed our previous hypothesis that not only the arterial blood level of anesthetics but the rate of its increase are important factors determining the EEG pattern of anesthesia.(Avramov MN et al.: Effects of different speeds of induction with sevoflurane on the EEG in man. J Anesth 1: 1–7, 1987)  相似文献   
63.
Two model substrates for oxidative hepatic enzyme activity, viz. antipyrine (A) and theophylline (T), were given simultaneously to rats by iv administration. Blood concentrations of A and T were measured by a high-performance liquid chromatographic (HPLC) method. Urinary excretions of A, T, and the major metabolites arising from A—4-hydroxyantipyrine (OHA), norantipyrine (NORA), 3-hydroxymethylantipyrine (HMA), and 4,4-dihydroxyantipyrine (DOHA)—and from T—1-methyluric acid (1-MU) and 1,3-dimethyluric acid (1,3-DMU)—were also determined by HPLC. It was found that the pharmacokinetic parameters obtained after the simultaneous administration of A and T at relatively low dose levels (A, 5.0 mg; and T, 1.3 mg) were not different from those obtained after the separate administration of A or T at the same dose level. In order to investigate whether the metabolic pathways of A and T are mediated by the same or closely related forms of the cytochrome P-450 system, metabolic clearances of A (CLA,M) and T (CLT,M) and the clearances for production of their various metabolites, obtained in untreated rats and in rats pretreated with 3-methylcholanthrene (MC) or with MC followed by 9-hydroxyellipticine (E), were correlated. These two compounds are a selective cytochrome P-448 inducer and inhibitor, respectively. Strong correlations were found between CLT,M and the clearances for production of OHA, NORA, and DOHA but not HMA. The best correlation, however, was observed between CLT,M and CLOHA, not only when all data points were taken into account (r = 0.99), but also in separate pretreatment groups (r ranging from 0.87 to 0.92). Moreover, the slopes of these correlation lines varied only slightly among groups, while the intercepts were not significantly different from zero. In the separate pretreatment groups, the correlation coefficients for the correlations between CLT,M and the clearance for production of the other metabolites of A were considerably lower, while the slopes of the correlation lines varied substantially. Clearances for production of the metabolites of T were strongly correlated with each other (r = 0.99) and with CLOHA (r = 0.95). It can be concluded that theophylline metabolism and formation of OHA are mediated by the same or very similar forms of cytochrome P-450, whereas formation of the other major metabolites of A is not or only partly. The study of the various pathways of metabolism after simultaneous administration of drugs is a powerful tool in the study of correlations in drug metabolism in vivo.  相似文献   
64.
目的探讨足月经产妇使用地诺前列酮栓促宫颈成熟的置药特点、引产特征和安全性,以指导其临床应用。方法回顾性分析首都医科大学附属北京世纪坛医院产科2019年1~10月收治的237例Bishop评分≤6分、阴道放置地诺前列酮栓促宫颈成熟的足月妊娠孕妇资料,其中经产妇34例,初产妇203例,比较两组产妇的置药时长、取药原因、用药至临产时长、产程时间、临产时间、产后出血量、新生儿Apgar评分、胎儿窘迫、新生儿窒息、药物不良反应等情况。结果经产妇组置药时长较初产妇组缩短[(5.78±3.85)h vs(8.54±5.82)h],差异有统计学意义(P<0.05)。经产妇因宫颈条件改善取药的占比大于初产妇,经产妇用药至临产时长[(4.75±7.78)h vs(11.38±13.80)h]、产程时间[(4.24±1.06)h vs(8.19±5.41)h]均小于初产妇,差异有统计学意义(P<0.05)。经产妇24 h内临产率为94.12%,初产妇为77.34%,差异有统计学意义(P<0.05)。两组产后出血、胎儿宫内窘迫发生率、新生儿窒息率、新生儿1 min Apgar评分、药物不良反应发生率比较,差异无统计学意义(P>0.05)。结论足月经产妇使用地诺前列酮栓促宫颈成熟安全、有效。临床操作中应严密观察宫颈变化及宫缩情况并及时取药,密切关注产程进展,加强不良反应监测。  相似文献   
65.
为了探讨米非司酮配伍米索前列醇在中期妊娠引产中的疗效 ,观察组 68例用米非司酮配伍米索前列醇引产 ,对照组 60例用利凡诺引产 ,观察两组从规律宫缩至胎儿娩出时间 .结果 :观察组从规律宫缩至胎儿娩出时间孕 2 0周前及孕 2 0周后分别是 ( 6 5± 0 5 2 )h和 ( 7 6± 0 4 8)h均比利凡诺组的 ( 13 2± 2 4 )h和 ( 11 1± 0 3 )h明显缩短 (P <0 0 5 ) ;而且孕 2 0周后观察组胎盘胎膜完全排出率 ( 3 8 8% )明显高于对照组 ( 2 0 % ) (P <0 0 5 ) .结论 :米非司酮配伍米索前列醇用于中孕引产具有安全有效、简便易行、无严重副作用的优点 ,是一种值得推广、使用的方法 .  相似文献   
66.
目的 在地塞米松磷酸钠诱导下建立大鼠卡氏肺孢子虫肺炎的动物模型。方法 将40只雌性SD大鼠随机分为实验组和对照组,前者皮下注射地塞米松磷酸钠,1mg/次,2次/w;后者不做任何处理。观察两组大鼠的发病情况,并每隔3周两组各取5只动物进行病原学检查。结果 实验组大鼠第6周开始发病,肺印片、支气管肺泡灌洗液沉渣中查到卡氏肺孢子虫包囊及滋养体;对照组大鼠无异常表现,病原学检查阴性。结论 在地塞米松磷酸钠诱导下可成功建立大鼠卡氏肺孢子虫肺炎动物模型。  相似文献   
67.
目的 :探讨一氧化氮 -环磷酸鸟苷 (NO- c GMP)通路在支气管哮喘发病机制中的作用。方法 :给 10名健康人、13例缓解期哮喘病人及 2 9例发作期哮喘患者诱导痰液 ,检测诱导痰液中 NO2 - /NO3- 及 c GMP的水平。并对其中 11例哮喘发作期患者应用强的松 (30 mg/d) ,治疗 1周的前后进行自身对照研究。结果 :哮喘发作期患者 NO2 - /NO3-水平显著高于健康对照者 [(4 0 6 .34± 5 12 .18) μmol/L,(71.80± 10 0 .98) μmol/L,P<0 .0 1],应用激素后患者在症状、体征好转的同时 ,NO2 - /NO3-和 c GMP的水平均有明显下降 ,稳定期哮喘患者的 NO2 - /NO3-水平同正常人相比差异无显著性。结论 :NO- c GMP通路可能在哮喘的发病中起重要作用 ,诱导痰 NO2 - /NO3- 的测定是无创伤性检测哮喘气道炎症的一项简便易行的实用方法。  相似文献   
68.
汤华 《南京军医学院学报》2001,23(4):236-237,239
目的:分析影响急性白血病诱导缓解的因素。方法:总结64例急性白血病的治疗情况,分析判断包括年龄、白血病类型、骨髓原始加幼稚(或早幼粒)细胞比例、周围血白细胞计数、有无肝脾肿大等因素与完全缓解(CR)率的关系。结果:不同年龄、周围血白细胞计数的CR率差异有显著意义(P<0.05)。白血病类型、骨髓原始加幼稚(或早幼粒)细胞比例、有无肝脾肿大的CR率差异无显著意义(P>0.05)。结论:高龄(≥60岁)和高白细胞急性白血病(周围血白细胞计数≥100×109/L),CR率低,预后差。  相似文献   
69.
目的 :验证从牛皮质骨中提取的骨形态发生蛋白 (bBMP)的异位诱导成骨能力 ,探讨煅桡骨 (SB)作为其载体对骨缺损的治疗作用。方法 :①将bBMP植入 1 6只balb/c小鼠肌袋内 ,每周宰杀 4只行细胞学检查 ,连续 4周。② 1 6只新西兰大白兔手术造成双侧桡骨 1cm缺损 ,分别植入bBMP -SB和SB进行自身对照 ,分批宰杀后行X -线照片和组织学检查。结果 :植入肌袋内的bBMP术后一周即可诱导软骨细胞形成 ,2周时可见编织骨 ,4周时可见小梁骨及骨髓成形。而骨缺损实验中 ,bBMP -SB组在软骨诱导、小梁骨的形成数量、骨折愈合等方面均明显优于单纯SB组。结论 :①bBMP有强大的异位诱导成骨能力 ;②bBMP -SB复合骨可促进骨缺损愈合  相似文献   
70.
BackgroundInduction of labor continues to become more common. We analyzed induction of labor and timing of obstetric and anesthesia work to create a model to predict the induction-anesthesia interval and the induction-delivery interval in order to co-ordinate workload to occur when staff are most available.MethodsPatients who underwent induction of labor at a single medical center were identified and multivariable linear regression was used to model anesthesia and delivery times. Data were collected on date of birth, race/ethnicity, body mass index, gestational age, gravidity, parity, indication for labor induction, number of prior deliveries, time of induction, induction agent, cervical dilation, effacement, and fetal station on admission, date and time of anesthesia administration, date and time of delivery, and delivery type.ResultsA total of 1746 women met inclusion criteria. Associations which significantly influenced time from induction of labor to anesthesia and delivery included maternal age (anesthesia P <0.001, delivery P =0.002), body mass index (both P <0.001), prior vaginal delivery (both P <0.001), gestational age (anesthesia P <0.001, delivery P <0.018), simplified Bishop score (both P <0.001), and first induction agent (both P <0.001). Induction of labor of nulliparous women at 02:00 h and parous women at 04:00 or 05:00 h had the highest estimated probability of the mother having her first anesthesia encounter and delivering during optimally staffed hours when our institution’s specialty personnel are most available.ConclusionsTime to obstetric and anesthesia tasks can be estimated to optimize induction of labor start times, and shift anesthesia and delivery workload to hours when staff are most available.  相似文献   
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