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61.
青蒿琥酯皮肤擦剂在小鼠和兔体内的药代动力学研究 总被引:1,自引:0,他引:1
将青蒿琥酯溶于苯二甲酸二甲酯,加适量氨酮制成皮肤擦剂。给兔脱毛后,皮肤涂抹此擦剂25mg/kg后,血药浓度达峰时间平均为2 h,峰浓度平均为1.80μg/ml。药物在兔体内平均驻留时间为3.54 h,清除半衰期约为2.46 h。给小鼠脱毛皮肤涂抹擦剂6.7,31.3和71.4 mg/kg,血药浓度在给药后0.5~4 h达高峰,峰浓度分别为0.82,2.05和7.11μg/ml,体内药物平均驻留时间为3.39,2.79及3.54 h,清除半衰期为2.35,1.93及2.45 h。可见,给兔及小鼠皮肤擦剂后,青蒿琥酯吸收良好,血药浓度维持时间较长。 相似文献
62.
Skoug John W. Borin Marie T. Fleishaker Joseph C. Cooper Anne M. 《Pharmaceutical research》1991,8(12):1482-1488
The mechanism of release from sustained-release adinazolam mesylate tablets was assessed by the Higuchi equation and by analysis of drug release profiles through 60% released using the Peppas equation. Computed values of the diffusional exponent, n, ranged from 0.59 to 0.66. Values of n in this range are consistent with a mixed mechanism of release, with diffusion of drug through the hydrated polymer matrix and relaxation of this matrix being the principal processes controlling release. The rate of in vitro drug release was increased for half tablets relative to whole tablets and is attributed to an increase in the surface to volume ratio of half tablets of about 16%. This increase in surface-to-volume ratio of half tablets was reflected by an increase in the constant, k, from the Peppas equation of 20–23% and by an increase in the slope of Higuchi plots of 12–18% for four lots of tablets. In vivo/in vitro relationships from two bioavailability studies were thoroughly evaluated. Using either a linear or a quadratic relationship, an in vivo/in vitro correlation exists for sustained-release adinazolam mesylate tablets. 相似文献
63.
64.
C. COLETTE M. C. GOUTTEBEL† L. H. MONNIER B. SAINT-AUBERT† H. JOYEUX† 《European journal of clinical investigation》1986,16(4):271-276
Seventeen patients who had undergone extensive small bowel resection were studied for calcium absorption (FACa) and plasma vitamin D metabolites. FACa was measured by a double radio-tracer technique and expressed as percentage of total oral dose. FACa was decreased compared with controls (34%, range: 3-46 v 65%, range: 57-73, P less than 0.01). A positive correlation (r = 0.49, P = 0.05) was found between FACa and the remaining length of small bowel (SBL). As wide variations in both SBL and duration after surgery were observed among the seventeen investigated patients, we were led to individualize less heterogeneous subgroups of patients. Better correlations were found when the patients were divided into two subgroups according to whether the time interval between the resection and the investigation was shorter (r = 0.75, n = 11, P less than 0.02) or longer (r = 0.89, n = 6, P = 0.05) than 2 years. In thirteen patients who had a SBL shorter than 100 cm, a positive correlation was observed between FACa and the time interval after surgery (months): r = 0.65, P less than 0.05. Plasma 1,25 (OH)2D was markedly reduced in the whole group (31 pmol l-1, range: 8-108) compared with controls (103 pmol-1, range: 59-134, P less than 0.01). The present study shows that in extensively small bowel resected patients, calcium absorption is reduced, the alteration being dependent both on the length of the remnant small bowel and on the time after surgery.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
65.
目的评价以髂深血管为蒂的髂骨—腹内斜肌双岛状瓣(简称同蒂双岛状瓣)修复下颌复合组织缺损的临床应用价值。方法2005年1月至2006年10月,应用同蒂双岛状瓣修复10例下颌骨复合组织缺损(包括下颌骨体部、下颌角和下颌骨升支及其周围软组织,其中有7例还包含髁突的缺损)。结果10例同蒂双岛状瓣移植均获成功,仅1例出现局部轻度感染,换药后二期愈合。术后随访3~24个月,均无肿瘤复发,颌面外形两侧基本对称,咬合关系恢复正常,且供区未见明显的并发症。结论同蒂双岛状瓣具有切口隐蔽、单一,对供区功能影响小,软硬组织复合缺损同期修复效果好等特点,是半侧下颌骨复合周围软组织大型缺损功能重建的较好方案。 相似文献
66.
目的:探讨头皮电烧伤骨外露用头皮扩张皮瓣移植修复的临床效果。方法:采用早期扩创,保留部分坏死骨质,用邻近头皮扩张使带毛发的头皮面积扩大后移植覆盖创面,电性失活骨质在血循环良好的皮瓣覆盖下,为周边及基底健康骨质生长起到支架作用,皮瓣扩张到一定面积后移植到裸露骨质上,使其得以修复。结果:在治疗的9例中,除1例皮瓣边缘在1.5cm×1.5cm坏死外,其余皮瓣全部成活,未发生感染坏死,创面均一次性封闭。结论:头皮电烧伤骨外露扩张后皮瓣带毛发修复,可缩短创面愈合时间,外形较好,易掌握,效果较为满意。 相似文献
67.
小骨窗术和碎吸术治疗脑出血的临床应用研究 总被引:2,自引:0,他引:2
目的对比研究颅内血肿小骨窗清除术和颅内血肿(钻孔)碎吸清除术治疗脑出血的疗效。方法87例脑出血患者分为小骨窗组(行颅内血肿小骨窗清除术)、碎吸组(行颅内血肿碎吸清除术)和对照组(行内科保守治疗)。分别比较小骨窗组、碎吸组、保守组治疗前后的GCS评分及3组的GCS评分差。采用t检验、χ2检验和单因素方差分析比较。结果小骨窗组、碎吸组与保守组的GCS评分差比较均有差异(P<0.05);小骨窗组和碎吸组的GCS评分差比较也有差异(P<0.05)。结论小骨窗颅内血肿清除术、碎吸颅内血肿清除术、内科保守疗法在脑出血治疗中均能发挥一定的作用。小骨窗术和碎吸术在治疗中均能提高疗效、加快神经功能恢复,但小骨窗术较碎吸术能更好地发挥疗效、提高病人的生存质量。 相似文献
68.
Summary Bayesian analysis is given of a random effects binary probit model that allows for heteroscedasticity. Real and simulated examples illustrate the approach and show that ignoring heteroscedasticity when it exists may lead to biased estimates and poor prediction. The computation is carried out by an efficient Markov chain Monte Carlo sampling scheme that generates the parameters in blocks. We use the Bayes factor, cross‐validation of the predictive density, the deviance information criterion and Receiver Operating Characteristic (ROC) curves for model comparison. 相似文献
69.
Philip F. Giampietro MD PhD Margaret G. E. Peterson PhD Robert Schneider MD Jessica G. Davis MD Stephen W. Burke MD Oheneba Boachie-Adjei MD Charles M. Mueller PhD RD Cathleen L. Raggio MD 《HSS journal》2007,3(1):89-92
Reduced bone mineral density (BMD) was sporadically reported in patients with Marfan syndrome. This may or may not place the
Marfan patient at increased risk for bone fracture. In comparing the BMDs of our patients with those reported in the literature,
it seemed that agreement between values, and hence the degree of osteoporosis or osteopenia reported, was dependent on the
instrumentation used. The objective of this study was to statistically assess this impression. Bone mineral density measurements
from our previously published study of 30 adults with Marfan syndrome performed on a Lunar DPXL machine were compared with
studies published between 1993–2000 measured using either Lunar or Hologic bone densitometry instruments. The differences
of our measurements compared with those made on other Lunar machines were not statistically significant, but did differ significantly
with published results from Hologic machines (P < 0.001). Before progress can be made in the assessment of BMD and fracture risk in Marfan patients and in the evidence-based
orthopedic management of these patients, standardization of instrumental bone density determinations will be required along
with considerations of height, obesity, age, and sex. 相似文献
70.
目的 研究h-BMP-2基因转染骨髓间充质干细胞(BMSCs)在复合煅烧骨、β-TCP或直接植入裸鼠股部后的成骨能力。方法 通过影像学、组织学和形态计量学等方法,观察未经诱导、OS液诱导和h-BMP-2基因转染BMSCs在复合煅烧骨,或多孔β-TCP后植入裸鼠皮下,或直接制成细胞悬液注入,在4、8、12周诱导成骨和材料降解情况。结果 在裸鼠皮下,单纯生物陶瓷不能诱导成骨,而复合了未诱导、OS液诱导和h-BMP-2基因转染BMSCs的生物陶瓷均能成骨,成骨量为h-BMP-2基因转染组>OS液诱导组>未经诱导组(P<0.05),B-TCP可随骨长入而降解;注入裸鼠肌肉的OS液诱导的和h-BMP-2转染的BMSCs均能诱导成骨,而未经诱导MSCs则不能成骨。结论 复合人BMP基因转染BMSCs的β-TCP是一种理想的骨修复材料。 相似文献