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51.
中药安迪对HL-60细胞分化的诱导作用 总被引:4,自引:1,他引:3
目的 探讨安迪粉针剂 (Andi)对 HL- 60细胞分化的诱导作用 .方法 采用人早幼粒白血病细胞株 (HL - 60 )为靶细胞 ,分为不加任何药物的对照组 (C组 )、安迪粉针剂 (Andi)组、阳性对照药维甲酸 (RA)组和苦参 (KS)组 ,进行体外培养和诱导分化 ,观测细胞生长曲线、细胞形态、硝基蓝四氮唑(NBT)还原和吞噬能力等指标 .结果 2 mg· L-1 Andi可显著地抑制 HL - 60细胞增殖 ,使原始细胞分化为中幼以下的成熟细胞 ,分化后的细胞具有 NBT还原能力和吞噬功能 ;Andi为 68.0 % ,RA为 61 .5% ,KS为 59.0 % ,C组还原能力仅6.0 % (P<0 .0 1 vs C) .其形态的改变和吞噬能力与阳性对照药维甲酸 (RA)和苦参 (KS)相似 ,分别为 52 .0 % ,45.5%和56.5% (P>0 .0 5) ;均明显高于空白对照组 .C组吞噬功能仅7.5% (P <0 .0 1 vs C)其 NBT还原能力与 KS相当 (P >0 .0 5) .结论 Andi对 HL - 60细胞具有显著的诱导分化作用 相似文献
52.
Two topical corticosteroids, budesonide (BUD) and beclomethasone dipropionate (BDP), both administered as suspensions in water, were investigated in healthy volunteers regarding influence on cortisol in plasma and urine (U-cortisol) after nasal application. In the first study, single doses of 200, 400, and 800 μg of BDP and BUD were given at 10:00 pm. In the second study, 100, 200, and 400 μg were given mornings and evenings for 4 days. In the single-dose study, none of the drugs or doses showed any significant influence on cortisol in plasma. However, U-cortisol decreased significantly after BUD 400 and 800 μg. In the multidose study, U-cortisol values were significantly reduced after all doses of BUD and the highest dose of BDP. The compounds tested showed different ability to cause measurable systemic effects after nasal application. The clinical implication is that the prescriber, when choosing a compound, should take the application site into consideration and should also be encouraged to find the lowest effective dose. 相似文献
53.
以S.minnesota R595菌为免疫原,通过细胞融合获得8株分泌抗核心糖脂单抗的杂交瘤细胞系。对其中的两株代表性单抗2D6E7和3H4 2F7的血清学反应性以及在小鼠Hb/Mu腹腔感染模型中的保护作用进行了初步研究。菌体吸收试验和间接免疫荧光试验(ⅡF)表明,单抗能与多种革兰氏阴性杆菌(GNB)产生交叉反应,并且光滑型GNB的煮沸菌体荧光染色呈阳性,活菌染色呈阴性。保护性试验结果表明,3H4 2F7单抗能显著提高S.minnesota(野生菌株),鼠伤寒杆菌和E.Coli等光滑型GNB攻击的小鼠存活率(P<0.05),显示出抗核心糖脂单抗的良好交叉保护作用。若攻击前、后2h或攻击同时输入单抗3H4 2F7,对光滑型GNB的感染均有明显保护效果(P<0.05);2D6 E7单抗未表现有保护活性。 相似文献
54.
化学染发剂和冷烫精的毒性及对人体健康影响的调查研究 总被引:7,自引:1,他引:6
本文通过化学染发剂和冷烫精对大白鼠骨髓多染红细胞,毛囊细胞的微核实验及人群健康影响调查,结果表明化学染发剂,冷烫清具有较强致突变作用,两者同时使用致突变明显增强,并提出研制高效无毒染发剂和加强防护的重要性。 相似文献
55.
NAOHIRO WATANABE YUKIFUMI NAWA KENICHI OKAMOTO AKIO KOBAYASHI 《Parasite immunology》1994,16(3):137-144
The roles of IgE and mast cells on expulsion of adult Hymenolepis nana from the intestine were examined in mice. IgE-dependency was determined by comparing congenitally IgE-deficient SJA/9 and IgE-producing SJL/J mice infected with 50 H. nana eggs. Anti-H. nana IgE antibody was detected at three weeks post infection (p.i.) in SJL but not in SJA mice. The number of adult worms in the intestines of SJA and of SJL mice were similar at two weeks, but significantly more were found in SJA mice at three weeks p.i. Treatment of mice with anti-ɛ antibody also resulted in an increased worm burden at three weeks, suggesting participation of IgE in expulsion of H. nana. Intestinal mastocytosis was induced by infection regardless of the IgE status of the mice. Mast cell-dependency was tested in mast cell-deficient W/Wu and in normal littermate +/+ mice infected with 100 H. nana eggs. Anti-H. nana antibody was detected in both groups of mice at three weeks p.i. Worm expulsion seemed to be mast cell dependent because expulsion was less complete in W/Wu mice at three weeks p.i. Peripheral blood eosinophilia was comparable at three weeks p.i. in both IgE and mast cell sufficient and deficient mice. These results suggest that IgE and mast cells participate in the expulsion of H. nana adults from intestine in mice. 相似文献
56.
Matilde Valencia-Flores David N. Velázquez-Martínez Julían E. Villarreal 《Psychopharmacology》1990,102(1):136-144
The chronic exposure of rats to a schedule of operant water reinforcement coupled with chronically restricted access to water sensitized the animals to intermittentd-amphetamine injections (0.31–2.5 mg/kg with intervals of 12–23 days between any two injections) in such a way that this drug came to produce catastrophic losses of body weight (32.4% of control levels). In the sessions whend-amphetamine was administered, the rats were also given a total of 12 brief electric shocks. Loss of body weight was unaccompanied by parallel changes in operant behavior performance, or in food or water intake. Remarkably, in other studies with the same interventions (sham schedule sessions, water deprivation, and foot shocks), with the exception that reinforcers were never delivered,d-amphetamine did not produce catastrophic falls in body weight. This super-reactivity tod-amphetamine toxicity may be mediated by a possible stressor action of the schedule of reinforcement. Its mechanism might be analogous to the known sensitization produced by classical experimental stressor stimuli to the repeated administration ofd-amphetamine. 相似文献
57.
M N Martinez F R Pelsor V P Shah J P Skelly I L Honigberg S M Hemingway J M Gallo J A Kotzan R Zaman W J Brown 《Biopharmaceutics & drug disposition》1990,11(1):17-29
Quinidine gluconate 324 mg sustained release tablets (Quinaglute) was administered as a single dose to 15 healthy male subjects following an overnight fast, immediately following a high fat (HF) breakfast or immediately following a low fat (LF) breakfast. Serum samples were obtained over a 48 h period and analyzed for quinidine content using a high performance liquid chromatographic assay. Under the conditions of the study, both the rate and extent of quinidine bioavailability was significantly affected by food. The extent of bioavailability was statistically significantly greater (p less than 0.05) following both the HF and LF meals as compared to that in the fasted state. Rate of bioavailability was significantly enhanced following the LF meal as compared to that of the other two treatment groups. Although peak concentrations were greater and time to peak concentrations somewhat later following the HF meal versus those under fasting conditions, these differences were not statistically significant. In addition, the characteristics of the serum concentration-time profile (as defined by the number, magnitude, and time of occurrence of the multiple absorption maxima) was unique for each of the three treatment groups. Possible mechanisms underlying these results are explored. 相似文献
58.
J. Boldt H. A. Adams B. Zickmann D. Kling G. Hempelmann 《European journal of clinical pharmacology》1990,38(5):431-436
Summary The release of endogenous catecholamines in aorto-coronary bypass graft patients receiving either 0.5 mg/kg enoximone (n=10), 4.0 mg/kg theophylline (n=10) or saline solution (control,n=10) has been studied, as well as certain haemodynamic parameters. Adrenaline (A) and noradrenaline (NA) concentrations were
not significantly changed by the administration of enoximone. Theophylline caused a small increase in NA (+ 40% in the 1st
min) and a marked increase in A (approximately + 7000% in the 1st min), which still remained elevated at the end of the investigation
period (+ 220% in the 30th min). The major haemodynamic effects of enoximone were a significant increase in cardiac index
(CI; + 35%) and a decrease in pulmonary capillary wedge pressure (PCWP; −27%), pulmonary artery pressure (PAP; −21%), RVEDV
and RVESV, while the heart rate (HR) remained almost unchanged. The dominant haemodynamic effects of theophylline were an
increase in HR (+ 26%; arrhythmia in 3 patients), PAP (+ 22%), and RVEDV (+ 19%), while REVESV (+ 26%), MAP (−16%), CI (−14%),
and RVEF (−15%) fell significantly.
It is concluded that the haemodynamic actions of enoximone are not mediated by catecholamine release, whereas the adverse
cardiovascular effects of theophylline might partly be explained by the significant increase in plasma adrenaline. 相似文献
59.
60.
The authors present the third installment of the guidelines and recommendations from the Safety Committee of the Society for Magnetic Resonance Imaging (now the Society of Magnetic Resonance) concerning various issues related to the safety and management of patients undergoing magnetic resonance (MR) procedures. This document was developed to provide standardized and consistent information for use by health practitioners involved in screening patients or other individuals for MR procedures. 相似文献