兽药长效制剂的研究进展

本文对兽药长效制剂的特点、产生与发展作以简要介绍，并着重阐述了长效制剂中最常见的两类剂型——缓释制剂和控释制剂近年来在国内外的应用情况，分析了长效制剂亟待解决的问题，并对其发展前景进行了展望。     

医用镁合金及其涂层生物相容性的研究进展

查阅近年来国内外镁合金生物相容性方面的相关文献,从血液相容性、细胞相容性、组织相容性等方面对镁基合金及其生物相容性研究进展进行了综述。     

LOOSENING OF TRANSOSSEOUSLY PLACED ANTEBRACHIAL SCREWS IN TWO DOGS

Radius and ulna fractures in two dogs were repaired by application of a bone plate to the cranial surface of the radius. In both dogs, two screws were placed through the radius and into the ulna. Return of function and bone healing occurred as expected; however, return of lameness at 5 and 7 months postoperatively was attributed to loosening of the transosseous screws. The lameness resolved following implant removal. Loosening of only the transosseous screws could have resulted from the normal motion between the radius and ulna.     

CO.SMM缓释型注射液的热稳定性研究

为考察SMM和TMP经B-环糊精包合后所制备的复方SMM缓释型注射液的稳定性,采用紫外分光光度法测定复方SMM缓释型注射液中2主药在不同温度下的含量,用初匀速法预测其有效期。结果,复方SMM缓释型注射液在室温25℃条件下,SMM的有效期为2．02a,TMP的有效期为2．13a,为评价该制剂的稳定性提供了依据。     

Subcutaneous fatty acid composition of steers finished as weanlings or yearlings with and without growth promotants

Background: The current study evaluated the subcutaneous fatty acid(FA) composition of calf- and yearling-fed stee with or without growth promoting implants. Crossbred steers(n = 112; 267 ± 5.0 kg) of the same contemporary group were allocated to one of four production system and implant strategy based treatments in a completely randomized design with a 2 × 2 factorial arrangement of treatments.Results: There were no interactions(P 0.05) between production systems and growth promoting implants for the total and individual subcutaneous FA. Yearling as opposed to calf finishing reduced(P 0.05) subcutaneous proportions of C20:3n-6, trans(t)12-18:1, C14:0, several minor cis-monounsaturated FA(c-MUFA; c9-14:1, c11-16:1,c11-18:1, c12-18:1, c13-18:1, c9-20:1 and c11-20:1), and increased(P 0.05) subcutaneous proportions of t11c15-18:2,total and individual branched-chain FA. Subcutaneous fat from steers implanted with growth promotants had higher(P 0.05) proportions of total polyunsaturated FA(PUFA), total n-6 PUFA, C18:2n-6 and individual t-18:1isomers(t6 to t10) compared to non-implanted steers.Conclusions: Overall, current findings show that production systems and growth promotants led to only minor differences in subcutaneous FA composition of beef steers.     

Effect of constant-release melatonin implants and prolonged exposure to a long day photoperiod on prolactin secretion and hair growth in mouflon (Ovis gmelini musimon)

The aims of this study were to examine whether mouflons exposed to constant long and short day photoperiods are able to exhibit an annual cycle of hair growth and moult, and prolactin (PRL) secretion. Mouflon ewes were assigned to three groups of treatment. Ewes were maintained, either under natural photoperiod (control, n=9), or received a series of subcutaneous melatonin implants from December to April (n=8), or were exposed to a constant long day photoperiod (16-h light:8-h dark; 16L:8D) during 18 months (n=7). Blood was collected weekly to determine PRL concentrations, and hair samples were clipped weekly from the base of the neck to measure the length of predominant hair. Under constant long days and with melatonin implants, mouflons expressed an annual rhythm of PRL secretion, even though these treatments modified the times of rise or falling of PRL concentrations throughout the year. Hair growth initiation was almost coincident with the summer solstice in both control and melatonin-implanted mouflons but occurred two months earlier in long day hold mouflons (P<0.001). Long day hold mouflons had a lower hair growth rate than control and melatonin-implanted mouflons (P<0.001), and at the end of the experiment, a shorter hair length (3.4±0.24 cm; P<0.01) than control (4.3±0.17 cm), and melatonin-implanted mouflons (4.2±0.12 cm). Our data support the conclusion that in mouflon, an endogenous circannual rhythm of PRL secretion exists, and that the seasonal cycle of hair growth and moult appears to depend, at least in part, on circulating levels of PRL.     

GHRP-6温敏型凝胶的制备及其对小鼠生长的影响

采用开环聚合法合成PLGA—PEG-PLGA共聚物,制备GHRP-6温度敏感型缓释凝胶并对其体外释药和对小鼠生长的影响进行研究。以PLGA—PEpPLGA为载体材料制备GHRP一6缓释凝胶制剂,采用BCA法测定体外释放度,并对体外释放数据用Korsmeyer-Peppas方程进行拟合;分别对分组小鼠皮下注射GHRP-6凝胶（2．0g／L）、GH—RP-6（2．0g／L）、空胶和生理盐水,隔周称重。结果表明合成产物符合PLGA—PEG-PLGA共聚物的特征,质量分数为15％、20％、30％的共聚物水溶液的胶凝化温度在32～37℃;GHRP-6在浓度为15％、20％、25％共聚物中释放出95％以上的药物分别需要16、18、20d,其释放曲线均符合Korsmeyer-Peppas方程模型,且具有良好的相关性;各组小鼠在注射35d后,GHRP-6凝胶组的累积增重分别比生理盐水组、空胶组、GHRP-6组高45．18％（P〈0．01）,39．090．4（P〈0．01）,21．80％（P〈0．01）。由此表明GHRP一6在凝胶中的释放达到预期要求,且对小鼠的生长有显著的促进作用,因此GHRP-6的PLGA—PEGPLGA凝胶有望开发成为一种长效促生长的注射制剂。     

补骨胶囊对骨质疏松大鼠牙种植体结合骨板形成的影响

目的 研究中药复方制剂补骨胶囊对骨质疏松大鼠牙种植体结合骨板形成的影响.方法 8月龄雌性SD大鼠45只随机分为假手术组、卵巢切除组和中药组.术后3个月确定骨质疏松模型建立后,在大鼠胫骨近中干骺端植入纯钛螺纹柱状种植体,术后第1天开始给中药组大鼠用补骨胶囊冲剂灌胃,其它两组灌服生理盐水.术后1、2、3个月分批处死大鼠,取...