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41.
主动载药法制备两亲性药物脂质体的研究进展 总被引:2,自引:1,他引:2
脂质体跨膜梯度主动载药方法主要有pH梯度法和硫酸铵梯度法.本文介绍了两亲性药物脂质体跨膜梯度载药方法的原理、制备工艺、影响包封率的因素等国内外研究进展. 相似文献
42.
华法林负荷量法抗凝治疗短暂性脑缺血发作的研究 总被引:1,自引:0,他引:1
目的 :观察华法林抗凝治疗短暂性脑缺血发作 (TIA)的安全性和疗效。方法 :2 0 0 3年 1月至2 0 0 4年 1月入院的TIA病人 ,适合抗凝治疗者 ,按Roberts依年龄调整华法林负荷量指南用药 ,对照组为 2 0 0 2年 1月至 2 0 0 3年 1月住院的TIA病人 ,并剔除用肝素治疗的病人。结果 :华法林组 10d内无脑卒中发生 ,仅有 4人次再次TIA ,未发现有出血者 ;对照组 10d内脑梗死 6例 ,再次TIA 12人次 ,华法林组于TIA发作后 10d内发生脑梗死及再次TIA较对照组低 (P <0 .0 5 )。结论 :按Roberts华法林负荷量指南抗凝治疗TIA优于非抗凝治疗 ,而且安全 相似文献
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《Connective tissue research》2013,54(4):241-264
Soluble substances in the bovine nuchal ligament were removed by preliminary extractions with a buffer and dilute alkali solution. The insoluble residue was then extracted with 6 M guanidine HCl and with 6 M guanidine HCl containing a reducing agent (20 mM dithiothreitol) successively. Each of the two extracts contained a glycoprotein; that in the first extract was designated Glycoprotein A and that in the second Glycoprotein B. They were purified by ion-exchange chromatography and gel filtration till essentially homogeneous. Both proteins had similar molecular weights of 35,000 in SDS-polyacrylamide gel electrophoresis and by gel filtration, and their chemical compositions resembled each other closely. It is suggested that Glycoprotein B was present in the native state as a disulfide-bonded, aggregated form of Glycoprotein A. The compounds also showed similarity with the microfibrillar glycoprotein(s) previously reported in bovine nuchal ligament extracts. 相似文献
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《Gait & posture》2021
BackgroundRunning induced-fatigue is an important factor in running related injuries. Runners with different strike types have different running mechanics and suffer from different injury patterns. Underlying mechanism of this difference is not well understood.Research questionThe aim of this study was to examine the effects of running-induced fatigue on plantar pressure distribution in runners with different strike types.Methods30 rearfoot (age = 21.56 ± 2.28 years; height = 1.67 ± 0.08 m; mass = 61.43 ± 11.57 kg; BMI = 21.77 ± 2.9 kg∙m−2) and 30 forefoot (age = 19.73 ± 1.68 years; height = 1.71 ± 0.08 m; mass = 65.7 ± 13.45; BMI = 22.53 ± 3.39 kg∙m−2) strike male and female recreational runners were recruited to this study. Participants ran in 3.3 m/s barefoot along the plantar pressure measuring device (Footscan®, Rsscan International) before and after running-induced fatigue. Fatigue protocol was performed on a treadmill. Peak plantar pressure and peak plantar force (% body weight), contact time and medio-lateral force ratio were calculated while running. Repeated measures ANOVA test was used to investigate the effect of running-induced fatigue on plantar pressure variables (p ≤ 0.05).ResultsAfter running-induced fatigue, in the rearfoot strike group, increases in loading of medial and lateral portions of the heel, first metatarsal and big toe was observed, and in lesser toes and in the forefoot push off phase, the medio-lateral force ratio decreased. While, in the forefoot strike group first to third metatarsals loading increased and fifth metatarsal loading decreased after fatigue, and medio-lateral force ratio in the foot flat and forefoot push off phase increased. In both groups contact time increased after fatigue.SignificanceOur data indicate that running-induced fatigue has different effects on plantar pressure distribution pattern in runners with different strike type. These different effects reflect different adaptation strategies in runners with different strike types, and could explain existence of different injury patterns in runners with different strike types. 相似文献
48.
The ordered mesoporous silicas SBA-15 and KIT-6, modified with lanthanum, have been for the first time applied in investigation of ibuprofen adsorption and release. The materials of hexagonal and regular structure were obtained by the hydrothermal method using a triblock copolymer Pluronic P123 as a template. The mesoporous silicas were impregnated with an aqueous solution of lanthanum(III) chloride in the amount necessary to obtain 1, 3 and 5 wt.% La loading. The physicochemical properties of the modified silicas were characterised by X-ray diffraction, transmission electron microscopy, UV–Vis spectrophotometry and low-temperature nitrogen sorption. The results showed that lanthanum strongly determined structural as well as textural properties of the silicas. The samples of modified silica were checked for the ability to adsorb and release of ibuprofen. The storage capacity of the modified silicas obtained increased with increasing their average pore diameter and percentage content of lanthanum. The amount of ibuprofen adsorbed onto KIT-6 silica modified with La was higher than that adsorbed onto SBA-15 materials. The high coverage of lanthanum on the surface of KIT-6 and SBA-15 solids was found to increase the amount of ibuprofen and the rate of its release. 相似文献
49.
《Gynécologie, obstétrique & fertilité》2014,42(10):732-740
The hypogonadotropic hypogonadism is an easily treatable form of female infertility. The most common cause of hypogonadotropic hypogonadism is functional hypothalamic amenorrhea. The GnRH pump is a simple and effective treatment to restore fertility of patients with hypothalamic amenorrhea: cumulative pregnancy rate is estimated between 70 and 100% after 6 cycles, compared to a low rate of complications and multiple pregnancies. While only 2.8 cycles are on average required to achieve a pregnancy with a pump, this induction of ovulation stays underused in France. The objective of this paper is to propose a practical manual of pulsatile GnRH, in order to improve the accessibility of pulsatile GnRH for patients with hypogonadotropic hypogonadism. 相似文献
50.
J.J. Londoño A.M. Ramos S.A. Correa M. Mesnard 《The British journal of oral & maxillofacial surgery》2021,59(5):546-554
In the last few years the dental implants market has grown both in developed and developing countries, and is associated with high aesthetic expectations and well-being. Although the success rate of commercial implants is high, some problems associated with a lack of initial stability, marginal bony resorption, and periodontal health, remain, especially with immediate placement and loading. The market offers different designs of dental implants, but cylindrical and tapered devices that are fixed to the bone via an external thread are dominant. One lesser-known but potentially useful design is the expandable dental implant (EDI). This paper presents a review of expandable dental implants that encompasses a survey of the literature, published patents, and available commercial devices. We found 15 articles: prospective human trials (n = 4), human case reports (n = 3), published independent discussions of other articles (n = 2), three big animal trials (n = 3), and in silico studies (n = 3). A total of 73 published patents were found and two expandable dental implants are commercially available to date. We propose a classification system that differentiates between the expansion mechanism and the origin of the expanding action. Some expandable designs have been shown to provide good primary stability, but evidence to date is limited. We encourage future clinical and biomechanical studies to clarify and optimise the potential benefits of these implants. 相似文献