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1.
Different doses of hepatitis B virus vaccine—prepared by Korea Green Cross Corporation, were given to healthy infants born to HBsAg-negative mothers at birth, 1 and 6 months of age. A dose of 2 μg was administered intradermally in Group A and, in the three other groups, the vaccine was given intramuscularly (i.m.). An adequate follow-up observation was possible for 9 months after birth in 22, 25, 23 and 21 infants in Groups A, B, C and D, respecvely.
Group C (5 μg, i.m.) produced seroconversion most rapidly, showing the highest rate (96%) at 9 months of age. The lowest seroconversion rate (5%) was found at the age of 1 month in Group A subjects, but the rate increased to 91% after a booster dose was given at 6 months of age.
While it can be concluded that a 5 μg i.m. dose of vaccine at 0, 1 and 6 months of age is optimum for the immunization of infants in efficacy and economy, a 2 μg intradermal dose can also be considered as an immunogenic and economical regimen, though the immune response is slower and a special technique is required for immunization.  相似文献   
2.
15 patients with acute myeloid leukaemia (AML) were treated with low-dose cytosine arabinoside (LD ARA-C). 2 patients had complete remissions, which lasted for 8 and 3 months, and 5 patients had a partial remission. 46% of the patients thus responded to LD ARA-C. This included 1 responding patient who had not previously responded to therapy with 6-mercaptopurine, thioguanine, or vinblastine. The 2 patients with complete remission did not show LD ARA-C-induced hypoplasia of bone marrow, although 1 had hypoplastic AML before therapy. Leukaemic cells from 1 patient showed in vivo maturation from M1 to M3 after LD ARA-C treatment. The present results, together with the published data, indicate that: a. LD ARA-C treatment, although it may have some toxic effects, is an effective treatment for some patients with AML, especially those with hypoplastic AML; b. Response to LD ARA-C can be obtained after one or several courses of treatment; c. LD ARA-C-induced remissions are sometimes obtained even in patients who fail in more conventional treatments; d. LD ARA-C-induced remissions can be achieved without bone marrow hypoplasia, and induction of hypoplasia by itself does not always result in complete remission; e. LD ARA-C can induce in vivo maturation of leukaemic cells. It is suggested that induction of remission in AML patients by LD ARA-C may result from either differentiation of leukaemic blast cells, cytotoxicity to leukaemic blasts, or both mechanisms acting together.  相似文献   
3.
目的 观察一次性小剂量米非司酮用于紧急避孕的效果。方法征集无保护性交或避孕失败后72小时内就诊并符合条件的健康妇女100例,单次口服米非司酮10mg。结果失败1例,按照Dixon方法计算,避孕有效率为89.55%;受试的月经周期无明显改变且未出现明显副作用。结论小剂量米非司酮单次口服用于紧急避孕简单、有效、安全。  相似文献   
4.
BACKGROUND: Low-dose allergen challenge (LDAC) may be a useful tool for studying the capacity of allergens to induce airway inflammation in atopic subjects. OBJECTIVE: To evaluate lower airway inflammatory changes following repeated inhalation of very low doses of allergen (VLDAC) in non-asthmatic subjects with allergic rhinitis (NAAR) compared with mild allergic asthmatic subjects (AA). METHODS: Fourteen NAAR and 11 AA were seen out of the pollen season and had skin prick tests with common aeroallergens. Baseline spirometry (S) and methacholine challenge (MC) were done and blood and induced sputum (IS) differential cell counts were obtained. Each subject underwent VLDAC on four consecutive mornings with a relevant allergen. S, MC, and blood and IS samplings were repeated 6 h after the second and fourth VLDAC and one week later. RESULTS: Although there were, as expected, no changes in FEV1 or PC20 in either group, mean percentage eosinophils on IS were significantly increased in NAAR on day 2 of VLDAC and decreased in all but one subject on day 4, with a tendency to return to baseline levels one week later. In AA, there was a non-significant trend for sputum eosinophils to increase on day 2; four subjects showed a decrease of eosinophils on day 4 of VLDAC. There was a correlation between eosinophil cationic protein (ECP) levels and eosinophil counts in NAAR throughout the study. There were no variations in other sputum cells or blood inflammatory cells. CONCLUSION: VLDAC can increase the percentage of eosinophils in IS of NAAR subjects without associated respiratory symptoms nor physiological modifications. A reduction in eosinophilic response despite repeated exposure, more common in NAAR subjects, suggests an adaptation process that needs to be further evaluated.  相似文献   
5.
Low-dose follicle stimulating hormone (FSH) regimens for induction of ovulation for women with polycystic ovaries have succeeded in reducing the rate of ovarian hyperstimulation syndrome (OHSS) almost to nil and the rate of multiple pregnancies to a minimum of 6%. This has been achieved by reaching, but not exceeding, the threshold level of FSH, starting with a daily dose of 75 IU for 14 days, using small incremental dose rises where necessary, and inducing uniovulation in 70% of cycles. Conception rates are as good, if not better, than those achieved with conventional therapy. The miscarriage rate is still relatively high (20-25%) and obese women fare worse. Serum oestradiol concentrations and the number of large and intermediate follicles on the day of human chorionic gonadotrophin administration are much lower, in parallel with lower serum FSH concentrations. Inhibin values increase with the rise in serum FSH concentrations but those of luteinizing hormone decrease steadily throughout the follicular phase. New data using recombinant hFSH (rhFSH), rather than urinary gonadotrophin as the ovarian stimulant, demonstrate that treatment time is shortened. However, the ideal regimen has still to be formulated.  相似文献   
6.
目的:探讨200 IU hCG在控制性卵巢刺激(COS)过程的晚卵泡期替代hMG对COS的疗效。方法:回顾性分析行体外受精/单精子卵胞质内注射-冻融胚胎移植(IVF/ICSI-FET)患者资料共154例,进行154个COS周期,根据晚卵泡期是否应用200 IU hCG分为:A组,COS完全应用hMG(65个周期);B组,COS的早卵泡期应用hMG,晚卵泡期则应用hCG(200 IU/d)替代hMG(89个周期)。后续166个周期进行FET,其中,A组70个周期,B组96个周期。统计分析COS周期的用药情况、IVF/ICSI-FET结局。结果:B组的hMG用药剂量和用药时间分别显著少于A组(1 361.0±494.6 IU vs 1 782.7±475.2 IU,P0.05;7.3±2.3 d vs 9.5±2.0 d,P0.05);B组的成熟卵母细胞数显著多于A组(15.2±6.6 vs 11.6±5.7,P0.05);冻融胚胎移植中A、B组的临床妊娠率(64.29%vs 64.58%,P0.05)及活产率(80.00%vs 79.03%,P0.05)比较无统计学差异。结论:200 IU hCG能够在COS的晚卵泡期替代hMG,能安全、有效地维持卵泡生长发育,并且减少Gn的用量,避免卵巢过度刺激综合征(OHSS)发生。  相似文献   
7.
Objectives.?To investigate the effects of a low transdermal estradiol dose on bone metabolism and to compare it with both the standard dose and absence of treatment.

Methods.?In this study performed in a third-level academic center, 66 healthy postmenopausal women underwent hormone therapy (HT) with patches containing estradiol at standard (0.050 mg/day, HT50, 33 women) or low dosage (0.025 mg/day, HT25, 33 women) and 70 women were without treatment (NT). The values (mean of three samples) of several bone biochemical parameters were compared between groups after adjusting for confounding factors. Bone mineral density (BMD) was assessed (by dual-energy X-ray absorptiometry) in the spine and hip in all cases, and a second densitometry scan was performed in 44 women.

Results.?Bone turnover markers tended to show lower values in the treated groups, but significance was restricted to total alkaline phosphatase (NT vs. HT25, p < 0.05) and cross-linked N-telopeptides of type I collagen (NTX) (NT vs. HT25, p < 10?6; NT vs. HT50, p < 10?5). The loss of BMD observed in NT women, as assessed by the annual percentage change, was blocked in both the HT25 and HT50 women. No significant differences were detected between both HT groups.

Conclusions.?Low and standard dosages of transdermal estradiol were equally effective in controlling bone metabolism, as assessed by turnover markers. Additionally, NTX was confirmed as the most sensitive marker for detecting changes in bone resorption.  相似文献   
8.
目的探讨低剂量、短疗程的抗胸腺细胞球蛋白(ATG)治疗肾移植后早期激素耐受性排斥反应的疗效。方法15例肾移植后早期发生的激素耐受性排斥反应患者给予ATG 1 mg.kg-1.d-1,qod,总疗程4~10 d,观察其排斥反应逆转率、术后6mo内排斥反应再次发生率和感染发生率。结果ATG治疗(3.4±1.5)次后,15例患者中12例逆转(80%),肾功能良好;2例(13.3%)治疗有效,未行肾切除;1例(6.67%)无效,血透维持。术后6 mo内3例(20%)再次发生排斥反应,3例(20%)术后40d内发生肺部感染。随访期内受体存活率100%。结论低剂量、短疗程的ATG治疗能有效地逆转肾移植后早期激素耐受性排斥反应,且减少了感染及严重并发症的发生机会。  相似文献   
9.
目的探讨首次辐照不同低剂量的超声对HIFU消融兔肝VX2瘤的影响。方法 45只荷瘤兔按随机数字表法分为3组:A组首次辐照功率为0W,B组80W,C组100W;均于第2天接受声功率为180W的消融治疗。结果产生相同的凝固性坏死体积B组所用的时间较A组少(P<0.05);B组与C组达到消融坏死的时间无明显差异,但C组所产生的凝固性坏死体积更大(P<0.05);3组比较,A组的能效因子(energy efficiency factor,EEF)值(46.43±13.67)最大,C组最小(7.01±1.33,P<0.05)。结论首次低剂量辐照的功率越大,增效作用越明显。  相似文献   
10.
Song W  Jin ZY  Wang Y  Xu Y  Yan HZ 《中国医学科学院学报》2006,28(1):49-52,i0010
目的 探讨16层螺旋CT低剂量扫描在气管支气管狭窄及闭塞诊断中的应用价值。方法 对28例胸部平片发现肺门或肺内异常患者行16层螺旋CT低剂量扫描和纤维支气管镜检查,以纤维支气管镜检测结果为金标准,计算低剂量CT气管支气管多平面及曲面重建图像发现气管支气管狭窄及闭塞的敏感度、特异度和准确度。结果 16层螺旋CT低剂量扫描发现中心气道、段支气管狭窄及闭塞的敏感度、特异度和准确度分为别91.3%、98.1%,97.6%、86.7%和97.9%、97.6%,其与纤维支气管镜检查对中心气道的诊断结果不存在偏差(P=0.257),但对段支气管的诊断结果存在偏差(P=0.035)。气管支气管多平面及曲面重建图像与纤维支气管镜检查显示中心气道及段支气管正常、狭窄、闭塞有显著一致性(P〈0.001),显示中心气道的一致性好(Kappa=0.846),显示段支气管的一致性中等(Kappa=0.694)。结论 16层螺旋CT低剂量扫描的气管支气管多平面及曲面重建可准确显示气管、支气管的狭窄和闭塞,有效应用于临床。  相似文献   
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