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51.
Summary A system which can be used for injection or infiltration of large volumes of fluid is described. This consists of a syringe which fills automatically from a reservoir through an inlet/outlet valve.  相似文献   
52.
Zero-order release of oxprenolol hydrochloride was obtained by controlling the swelling and erosion of the matrix. This formulation involves only mixing of drug, hydroxypropylmethylcellulose (HPMC), and sodium carboxymethylcellulose (Na CMC) at the ratio of 1:0.4:1.6, respectively, and compressing the mixture directly into tablets. The in vitro release pattern from this optimized matrix tablet was reproducible. Accelerated stability studies revealed that the optimized formulation remains stable for an approximately 2-year shelf life. This sustained-release (SR) tablet was evaluated in dogs, and for comparison a conventional (CV) formulation was also given at the same dose level. Plasma oxprenolol levels were monitored by a sensitive and specific high-performance liquid chromatographic (HPLC) method. Significant differences in the pharmacokinetic parameters, i.e., lower C max, higher values of t max, MRT, AUC, and plasma concentration at 24 hr, and nearly constant plasma levels over 12 hr, indicated that the SR matrix tablet is superior to the CV rapid-releasing formulation. The in vitro release parameters and in vivo pharmacokinetics correlated well.  相似文献   
53.
孔令英  刘瑞波  王建辉 《中国骨伤》2007,20(12):833-835
目的:通过与4枚斯氏针固定比较,利用生物力学方法评价多枚空心钉固定股骨转子骨折的适应证和可靠性。方法:使用Sawbone股骨模型,模拟EvansⅢA型骨折,分别用2种多枚空心钉方法(矩外空心钉和矩内空心钉法)及多枚骨圆针固定,在CSS-11101力学实验机上进行载荷试验,取300 N载荷下股骨头垂直位移和张口位移数值,比较3种方法的轴向刚度。通过扭转实验比较3种固定方法的抗扭转能力。结果:3种固定方法在轴向刚度方面差异有统计学意义(P<0.05),而抗扭转能力方面差异无统计学意义(P>0.05)。结论:矩外空心钉固定力学性能相似于4枚骨圆针,而矩内空心钉固定弱于4枚骨圆针。应用多枚空心钉固定应选择稳定型股骨转子间骨折。  相似文献   
54.
目的评价靶控输注咪唑安定对靶控输注丙泊酚镇静催眠效应的影响。方法ASAI~Ⅱ级择期手术患者40例,随机分为四组:A组为单纯丙泊酚组,B、C、D组为丙泊酚 咪唑安定组,咪唑安定靶浓度分别为10、20、30ng/mL。咪唑安定达到平衡后,血浆靶控输注丙泊酚。记录丙泊酚效应部位浓度为1、2、3、4、5μg/mL时BIS值和OAA/S评分,并记录OAA/S评分达到4、3、2、1时丙泊酚效应部位浓度和BIS值,记录BIS值为50时丙泊酚效应部位浓度。结果1.咪唑安定达到平衡后,C组和D组BIS值显著下降;D组中OAA/S评分也显著下降,并低于B组和C组;2.随丙泊酚浓度升高四组患者.BIS值和OAA/S评分逐渐下降;3.相同丙泊酚浓度时,BIS值和OAA/S评分随咪唑安定浓度增加呈降低趋势;4.B、C、D三组患者OAA/S评分达到3、2、1以及BIS值达到50时所需丙泊酚效应部位浓度均显著低于A组,达到相同OAA/S评分D组所需丙泊酚效应部位浓度显著低于B组和C组。结论效应部位浓度为10、20、30ng/mL的咪唑安定均能显著降低丙泊酚靶控浓度,以达到需要的镇静深度;随咪唑安定浓度加深,降低作用越明显。  相似文献   
55.
There is a scarcity of well-controlled studies of the seasonal variation in circadian rhythmicity. In the present study, the circadian phase of rectal temperature and the onset of slow wave sleep were studied in a series of twelve 24-h experiments, one each month of the year, for six healthy subjects under controlled conditions in a climatic chamber. In winter, as compared with summer, the average circadian rhythm of rectal temperature was phase delayed by 45 min, and the average onset of slow wave sleep was phase delayed by 40 min. The temporal relationship between the circadian phase of rectal temperature and the timing of slow wave sleep was maintained throughout the year. Habitual rising and retiring times covaried as well. Furthermore, the circadian rhythm of rectal temperature followed the timing of the photoperiod across the year, but had a much smaller range of seasonal variation. Apparently, the seasonal variation in the photoperiodic zeitgeber is largely compensated for by the stabilizing influence of secondary zeitgebers. However, in healthy subjects some effect of photoperiodic variation can still be observed.  相似文献   
56.
筛检对肝癌死亡率影响的研究   总被引:5,自引:0,他引:5  
5581名HBsAg阳性的男性随机分入周期性筛检组(A组,3712人)及对照组(B组,1869人)。A组(19155.4人年)共发生肝癌257例,B组(9785.5人年)为117例,两组的肝癌发生率分别为1342/10万与1196/10万;两组肝癌死亡分别为218与109例,肝癌死亡率分别为1138/10万与1114/10万。两组中Ⅰ期肝癌病例分别为29.6%与6.0%,差异有非常显著性意义。1、3、5年相对生存率A组为23.7%、7.0%、4.0%,B组为9.7%、4.0%、4.1%。用Poisson回归模型拟合显示,在调正年龄、初筛AFP及入列年份后,筛检对于肝癌的相对危险度为0.83,95%CI为0.68~1.03,有较弱的“保护”作用,Cox回归模型拟合结果显示当临床分期未引入模型时,筛检对于肝癌有显著的“保护”作用:危险率为0.6617,95%CI为0.5234~0.8365;而模型经调整后,危险率即接近“1”,95%CI为0.74~1.26。  相似文献   
57.
The objective of this study was to assess the effects of ascorbic acid supplementation, 500 mg twice daily in the treatment of pressure ulcers as an adjunct to standardized treatment.

The design consisted of a multicenter blinded randomized trial. The control group received 10 mg of ascorbic acid twice daily.

Patients from 11 nursing homes and 1 hospital participated.

Main outcome measures included wound survival, healing rates of wound surfaces, and clinimetric changes over 12 weeks.

Eighty-eight patients were randomized. Intention-to-treat analysis showed that the wound closure probability per unit time (i.e., the closure rate) was not higher in the intervention group than in the control group (Cox hazard ratio of 0.78 [90% precision interval, 0.44–1.39]). Mean absolute healing rates were 0.21 and 0.27 cm2/week in the intervention and control group, respectively (PI of the adjusted difference: −0.17 to 0.13). Relative healing rates and healing velocities did not show favorable results of ascorbic acid supplementation, either. A panel scored slides of the ulcers with a report mark between 1 (bad) and 10 (excellent). The improvement was 0.45 and 0.72 points per week in the intervention and control group, respectively (PI of the adjusted difference: −0.50 to 0.20). With another clinimetric index we could not show any differences, either.

These data do not support the idea that ascorbic acid supplementation (500 vs. 10 mg twice daily) speeds up the healing of pressure ulcers.  相似文献   

58.
目的 探讨硝普钠结合控制性再灌注在预防肺缺血再灌注损伤中的作用及其机制。方法 将 1 4只猪随机分为对照组 (Ⅰ组 )和实验组 (Ⅱ组 )。对照组在去除肺动脉阻断 ,恢复自体血流前 ,给予控制性再灌注处理 (灌注液 :去白细胞∶改良Buckberg液 =4∶1 ,灌注压 1 8mmHg ,灌注时间 1 0min ,温度 37℃± 1℃ )。实验组在去除肺动脉阻断 ,恢复自体血流前 ,给予控制性再灌注 ,后经肺动脉以每分钟 1 .0 μg kg注入硝普钠 1 0min ,余处置同对照组。 0 .5 ,1和 2h后测血氧分压、肺血管阻力、肺顺应性及肺氧合功能变化 ,实验结束后 ,取肺组织测NO含量、MDA含量及肺含水量。结果 实验组的左肺氧合功能和肺顺应性明显好于对照组 (P <0 .0 5 )。肺循环阻力、丙二醛 (MDA)值及肺含水量均低于对照组 (P <0 .0 1 )。实验组肺中NO含量较对照组明显升高 (P <0 .0 1 )。结论 硝普钠结合控制性再灌注能明显降低肺缺血再灌注损伤 ,起到了较好的移植肺保护效果  相似文献   
59.
醒脑静注射液治疗肺性脑病31例疗效分析   总被引:5,自引:0,他引:5  
目的 :探讨醒脑静注射液治疗肺性脑病的临床疗效。方法 :采用随机分组对照法 ,将 6 1例肺性脑病患者分为加用醒脑静组 (治疗组 ) 31例和单纯西药治疗组 (对照组 ) 30例 ,进行疗效对比分析。结果 :治疗组治愈12例 ,有效 15例 ,总有效率 87.10 % ;对照组治愈 5例 ,有效 16例 ,总有效率 70 .0 % ,2组疗效差异有显著性(P<0 .0 5 )。从时效关系看 :治疗组对意识障碍的起效时间〔(72 .0 0± 33.94 )小时〕明显快于对照组〔(117.71± 34.70 )小时 ,P<0 .0 1〕,表现为促醒时间短 ,意识恢复正常快 ,并能达到镇静安神的作用 ;从改善原发病症状、体征及血气指标看 :治疗组在改善头痛、失眠、多语、幻觉、谵妄、狂躁及喘憋等症状方面明显优于对照组 (P<0 .0 5 ) ,对降低 Pa CO2 效果亦明显优于对照组 (P<0 .0 1)。结论 :醒脑静注射液具有开窍醒脑、行痰通瘀、镇静止痉和清热解毒等功效 ,是防治肺性脑病的安全、有效药物。  相似文献   
60.
Breast feeding has nutritional, immunologic and antiallergicadvantages for the infant. Although it has been widely recommendedthat infants be exclusively breast fed until 4–6 monthsof age, only about half of all Australian babies currently receiveextended breast feeding. The present study evaluated an intensiveprogramme designed to increase the proportion ofprimi-parousmothers who breast fed for 4 months or longer. Women who registeredwith the hospital at least 20 weeks before delivery and whointended to breastfeed were eligible for the study. Two hundredand thirty-five women were allocated to receive either usualcare or an intensive breast feeding programme when they registeredwith the hospital. The intensive programme consisted of writtenmaterials, and group and individual sessions with a lactationcounsellor. It also included a visit from a breastfeeding consultantwhile in hospital after the birth and contact on return home.Women were followed up 6 weeks and 4 months after delivery.There were no significant differences in breastfeeding ratesbetween the control and intervention groups at either follow-uppoint. Breast feeding until 4 months was more likely among womenwhose baby did not receive a bottle feed while still in hospitaland who did not smoke, use the combined oral contraceptive pillor introduce solid food before 4 months. Those mothers who enjoyedand felt satisfied with breastfeeding were more likely to continueto 4 months. It seems likely that programmes designed to increasebreastfeeding will need to address underlying factors such ashospital policy rather than simply providing more health education.  相似文献   
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