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排序方式: 共有146条查询结果,搜索用时 265 毫秒
1.
BackgroundContact lens related keratitis is a frequent presentation to acute ophthalmology services. Patients often do not recall being counselled regarding the safe use of contact lenses therefore fail to comply with guidance.This study aimed to identify the content and format of advice given to patients with contact lens keratitis concerning appropriate hygiene practices, determine their compliance with this and finally characterise optometrist practices regarding contact lens advice provided to patients.MethodsAll adult patients presenting with contact lens related keratitis to the acute ophthalmology clinic were asked to complete a survey. Information was collected on lens type, format of advice received and compliance.Community optometrists were asked to complete an electronic survey on their contact lens review practices and routine patient education.ResultsAll patients surveyed recalled counselling on initiation of contact lenses; however 12% (6/50) were given no advice on return visits. This advice was in written format for 20% (10/50) of patients on initiation increasing to 32% (16/50) on renewal.Many patients slept (22%), showered (44%) or swam (36%) in lenses. 92% cleaned their contact lenses appropriately, but cases were washed infrequently (19% of cases cleaned < monthly) or with tap water (27%).All optometrists surveyed claimed to provide advice to patients in either written or verbal format for new and returning contact lens users. 49% (16/33) of optometrists gave written advice to patients on initial contact lens fitting, but only 1/33 continued with written advice for repeat customers.ConclusionThis study identified that although most patients were informed of appropriate hygiene requirements, compliance was poor. Optometrists regularly provide verbal advice but do not routinely offer written support and there is a mismatch between patient recollection and self-reported optometrist practice. It is suggested that patient education needs greater emphasis and both verbal and written information should be regularly provided on initial review and follow up assessments.  相似文献   
2.
目的分析经济欠发达地区农村居民对家庭便携式药包的需求,为科学设计适合农村居民使用的家庭便携式药包提供依据。方法对经济欠发达地区的江西省永新县芦溪乡卫生院、河北省平山县西柏坡镇卫生院、甘肃省临洮县新添镇中心卫生院的3个基本型卫生院辖区内的139户农村居民对家庭便携式药包的需求采用随机抽样与整群抽样相结合的方法及农村居民常用药品与药械问卷调查表进行调查。结果139户农村居民中,84.2%(117/139)的家庭期望拥有家庭便携式药包。芦溪乡、西柏坡镇、新添镇农村居民对家庭便携式药包需求率分别为:89.6%(43/48)、93.2%(41/44)、70.2%(33/47),芦溪乡、西柏坡镇农民居民对家庭便携式药包需求率均明显高于新添镇(P〈O.05)。117户农村居民期望在家庭便携式药包中能放置的药品分别为:感冒药(84.6%)、创口贴(63.2%)、风油精(51.3%)、清凉油(47.0%)、高血压用药(32.5%)、碘酊(31.6%)、其他用药(25.6%)、糖尿病用药(5.1%);农村居民期望便携式药包的大小为:长(25.84±7.51)cm,宽(18.25±7.18)cm,高(16.38±7.26)cm;农村居民期望家庭便携式药包的功能特点分别为:轻便(52.1%)、安全(50.4%)、适用(46.2%)、防水(45.3%)、经济(39.3%)、简单(36.8%)、防晒(28.2%)、防腐蚀(22.2%)、抗压(22.2%);农村居民期望家庭便携式药包的价格在≥10~〈15元(29.9%);在材质要求方面,86.3%农村居民倾向于硬材料,硬材料选择铝合金、塑料者分别占35.0%、34.2%;只有13.7%农村居民选择软材料,选择软材料者以帆布材料居多(6.8%)。结论基本型卫生院辖区内农村居民对家庭便携式药包的需求率较高。只有充分满足多数农村居民的需求,才能保证家庭便携式药包推广使用,从而减少农村居民的不合理用药。  相似文献   
3.
Support vector machines (SVM) and other machine-learning (ML) methods have been explored as ligand-based virtual screening (VS) tools for facilitating lead discovery. While exhibiting good hit selection performance, in screening large compound libraries, these methods tend to produce lower hit-rate than those of the best performing VS tools, partly because their training-sets contain limited spectrum of inactive compounds. We tested whether the performance of SVM can be improved by using training-sets of diverse inactive compounds. In retrospective database screening of active compounds of single mechanism (HIV protease inhibitors, DHFR inhibitors, dopamine antagonists) and multiple mechanisms (CNS active agents) from large libraries of 2.986 million compounds, the yields, hit-rates, and enrichment factors of our SVM models are 52.4–78.0%, 4.7–73.8%, and 214–10,543, respectively, compared to those of 62–95%, 0.65–35%, and 20–1200 by structure-based VS and 55–81%, 0.2–0.7%, and 110–795 by other ligand-based VS tools in screening libraries of ≥1 million compounds. The hit-rates are comparable and the enrichment factors are substantially better than the best results of other VS tools. 24.3–87.6% of the predicted hits are outside the known hit families. SVM appears to be potentially useful for facilitating lead discovery in VS of large compound libraries.  相似文献   
4.
Modified carboxymethyl chitosan (CMC) containing phosphatidylethanolamine (PEA) groups were synthesized by a 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC)-mediated coupling reaction. The structure of the modified CMC exhibiting an amphiphilic character was analysed by FT-IR and 1H NMR. CMC-g-PEA beads were prepared with sodium tripolyphosphate (TPP) by ionic-crosslinking. The beads sizes were in range from 800 to 1200 μm and encapsulation efficiencies of drug were more than 68%. The morphologies of CMC-g-PEA beads were examined with scanning electron microscopy (SEM). The release experiments were performed using ketoprofen as an hydrophobic model drug. The drug dissolution kinetics showed longer release times for CMC-g-PEA beads: 20 h (at pH 1.4) and 45 h (at pH 7.4). The amount of the drug release was much higher in acidic solution than in basic solution due to the swelling properties of the matrix at acidic pH. These results suggest that modified CMC with PEA may become a potential delivery system to control the release of hydrophobic drugs.  相似文献   
5.
Medicinal chemists are facing an increasing challenge to deliver safer and more effective medicines. An appropriate balance between drug-like properties such as solubility, permeability, metabolic stability, efficacy and toxicity is one of the most challenging problems during lead optimization of a potential drug candidate. Insoluble and impermeable compounds can result in erroneous biological data and unreliable SAR in enzyme and cell-based assays. The weak inhibitory activity and non-drug-like properties of monastrol, the first small mitotic kinesin Eg5 inhibitor, has hampered its further development. In this investigation, a bioisosteric approach was applied that resulted in the replacement of C-5 carbonyl of monastrol with thio-carbonyl. Further lead optimization of drug-like properties was evaluated through in silico predictions by using ADMET predictor software. This minor structural modification resulted in upgraded human effective jejunal permeability (Peff) and improved permeability in Madin–Darby canine kidney (MDCK) cells. Furthermore, C-5 thiocarbonyl analogue of monastrol (named as Special-2) was found safe to administer orally with no phospholipidosis toxicity, no raised levels of serum glutamate oxaloacetate transaminase (SGOT) and no potential towards cardiotoxicity. Molecular docking study was also carried out to understand the binding modes of these compounds. The docking study showed high binding affinity of the designed compounds against KSP. Hence a combination of in silico ADMET studies and molecular docking can help to improve prediction success and these compounds might be act as potential candidate for KSP inhibition.  相似文献   
6.
In the trade and raw drug market, the medicinal plants of genus Paris are available in the form of rhizomes without any vouchers, thus making it difficult to identify and distinguish the different species of Genus Paris. Recent studies have shown that the species of Paris possess different chemical constituents, pharmacological activities, and efficiencies in clinical application. To distinguish 11 species of Paris collected from the western Sichuan province of China and ensure their safety and efficacy, in the present work, the microscopic characteristics of rhizomes and the crude drug powder of the 11 species of Paris were compared using a light microscope according to the usual microscopic techniques. The results of the microscopic features were systematically described and illustrated. The differences among these species are great enough that the identity of most material can be easily determined. Also, semiquantitative and quantitative micrographic parameter tables were simultaneously presented. Further, the key authentication parameters based on these anatomic characteristics analyzed was drawn up and presented for the Paris species studied. The study indicated that light microscopy and related techniques could provide a method that is convenient, feasible, and can be unambiguously applied in the authentication of species of Paris. This information is required not only for the identification procedures that guarantee the utilization of the appropriate raw material, but also for the quality control standards demanded. Microsc. Res. Tech. 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
7.
Aim: The purpose of this study was to investigate the detailed mechanisms of oral absorption enhancement of bergenin (BN) using BN–phospholipid complex (BPC).

Methods: Multiple models such as ex vivo everted rat gut sac model and in vitro Caco-2 cell model were used. Meanwhile, the effect of chitosan on the enhancement of the permeability of BPC was evaluated.

Results: The limited absorption of BN was significantly improved in both ex vivo everted rat gut sac model and in vitro Caco-2 cell model when combined with phospholipid. The transport of BPC was uppermost 5.19-fold higher than that of BN. The results of ex vivo everted rat gut sac model showed that small intestine was a more suitable site for the absorption of BN and BPC than colon. Passive diffusion was the only way employed in the transport of BN, while BPC could transport across enterocytes by both passive diffusion and active transport which was found to be the clathrine-dependent receptor-mediated endocytosis. The absorption of BN was barely improved by the physical mixture of BN and phospholipid due to lack of stable intermolecular interactions. Moreover, the addition of chitosan could open the tight junctions of intestinal epithelial cells, thus significantly increasing the transport of BPC via paracellular route.

Conclusions: Totally different mechanisms, which led to the enhanced oral bioavailability, were utilized in the uptake and transport process of BPC compared with BN. These results would be of significance for the future development of oral delivery systems of BN.  相似文献   

8.
Bone-like apatite formation on porous calcium phosphate ceramics was investigated in static simulated body fluid (SBF) and dynamic SBF at different flowing rates. The results of a 14-day immersion in static SBF showed that the formation of bone-like apatite occurred both on the surface and in the pores of the samples. When SBF flowed at the physiological flow rate in muscle (2 ml/100 ml⋅min), bone-like apatite could be detected only in internal surface of the pores of samples. The result that bone-like apatite formation could only be found in the pores when SBF flowed at physiological flow rate was consistent with that of porous calcium phosphate ceramics implanted in vivo: osteoinduction was only detected inside the pores of the porous calcium phosphate ceramics. This result implicates that the bone-like apatite may play an important role in the osteoinduction of Ca-P materials. The dynamic model used in this study may be better than usually used static immersion model in imitating the physiological condition of bone-like apatite formation. Dynamic SBF method is very useful to understand bone-like apatite formation in vivo and the mechanism of ectopic bone formation in calcium phosphate ceramics.  相似文献   
9.
BACKGROUND: Lincomycin (LIN) is an antibiotic widely used in veterinary medicine to cure infections caused by Gram‐positive pathogens. Although the toxicity of LIN is not serious, it will cause adverse effects in humans, such as pseudomembranous enteritis and bacterial resistance. In this study, for the preparation of a LIN derivative, a novel modification method was adopted. The LIN derivative modified at 2‐position with a carboxylic group at the end of the spacer was synthesised and coupled to carrier proteins. A LIN polyclonal antibody‐based enzyme‐linked immunosorbent assay (ELISA) was developed and characterised. RESULTS: The ELISA standard curve was constructed with concentrations of 0.1–1000 ng mL?1. The IC50 value for nine standard curves was in the range 23.7–29.3 ng mL?1 and the limit of detection at a signal‐to‐noise ratio of 3 was 0.15–0.98 ng mL?1. The cross‐reactivity value of the LIN antibody with clindamycin hydrochloride, a homologue of LIN with similar molecular structure, was 18.9%, while less than 0.1% cross‐reactivity was found with seven other compounds. For LIN‐spiked food samples, the recoveries and relative standard deviation (RSD) were 76.6–117.6% and 1.7–34.6%, respectively. CONCLUSION: The proposed ELISA can be utilised as a sensitive and specific analytical tool for the detection of LIN in food samples. Copyright © 2010 Society of Chemical Industry  相似文献   
10.
目的 探索酶解法制备猪脾脏多肽的最佳条件,检测所得产物的生物活性.方法 用胰酶酶解法、正交试验、甲醛滴定法考察最佳酶解条件,用乙醇沉淀法收集多肽,并分别用Fe2+诱发卵黄脂蛋白多不饱和脂肪酸过氧化体系和纤维蛋白平板法检测多肽的抗氧化活性和溶栓活性,CM-Sepharose离子交换层析纯化最佳酶解条件F的脾多肽,利用SDS-PAGE电泳确定具备促凝活性的多肽分子片段相对分子质量.结果 最佳酶解条件为60℃,pH 7.0,加酶量6.0%,时间5.5 h;检测到脾多肽具备抗氧化活性和促凝活性,经纯化后的脾多肽促凝时间比正常对照提前20 s.结论 可初步判断猪脾脏多肽在抗氧化和凝血方面有一定作用,且首次证实猪脾多肽具有凝血功能.  相似文献   
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