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71.
目的:建立复方二氧化钛乳膏中水杨酸苄酯的含量测定方法.方法:采用反相高效液相色谱法(RP-HPLC).色谱柱Hypersil ODS C18(5 μm,4.6 mm×250 mm);流动相为甲醇-水(79∶21);紫外检测波长308 nm;流速1 mL*min-1.结果:水杨酸苄酯在5~30 mg·L-1的浓度范围内线性良好(r=0.9999),平均回收率为100.6%,RSD为1.17%(n=5);日内平均RSD为1.27%(n=5),日间平均RSD为1.57%(n=5).结论:该方法简便、快速、准确,可作为该制剂的质控方法. 相似文献
72.
Martina Lorenzetti Eva Pellicer Jordi Sort Maria Dolors Baró Janez Kova? Sa?a Novak Spomenka Kobe 《Materials》2014,7(1):180-194
The electrochemical behavior of polycrystalline TiO2 anatase coatings prepared by a one-step hydrothermal synthesis on commercially pure (CP) Ti grade 2 and a Ti13Nb13Zr alloy for bone implants was investigated in Hank’s solution at 37.5 °C. The aim was to verify to what extent the in-situ-grown anatase improved the behavior of the substrate in comparison to the bare substrates. Tafel-plot extrapolations from the potentiodynamic curves revealed a substantial improvement in the corrosion potentials for the anatase coatings. Moreover, the coatings grown on titanium also exhibited lower corrosion-current densities, indicating a longer survival of the implant. The results were explained by considering the effects of crystal morphology, coating thickness and porosity. Evidence for the existing porosity was obtained from corrosion and nano-indentation tests. The overall results indicated that the hydrothermally prepared anatase coatings, with the appropriate morphology and surface properties, have attractive prospects for use in medical devices, since better corrosion protection of the implant can be expected. 相似文献
73.
Nur Aziah Hanapi Ahmad Saifuddin Mohamad Arshad Jafri Malin Abdullah Tengku Sifzizul Tengku Muhammad Siti R. Yusof 《Journal of pharmaceutical sciences》2021,110(2):698-706
Neurotherapeutic potentials of Centella asiatica and its reputation to boost memory, prevent cognitive deficits and improve brain functions are widely acknowledged. The plant's bioactive compounds, i.e. asiaticoside, madecassoside and asiatic acid were reported to have central nervous system (CNS) actions, particularly in protecting the brain against neurodegenerative disorders. Hence, it is important for these compounds to cross the blood-brain barrier (BBB) to be clinically effective therapeutics. This study aimed to explore the capability of asiaticoside, madecassoside and asiatic acid to cross the BBB using in vitro BBB model from primary porcine brain endothelial cells (PBECs). Our findings showed that asiaticoside, madecassoside and asiatic acid are highly BBB permeable with apparent permeability (Papp) of 70.61 ± 6.60, 53.31 ± 12.55 and 50.94 ± 10.91 × 10?6 cm/s respectively. No evidence of cytotoxicity and tight junction disruption of the PBECs were observed in the presence of these compounds. Asiatic acid showed cytoprotective effect towards the PBECs against oxidative stress. This study reported for the first time that Centella asiatica compounds demonstrated high capability to cross the BBB, comparable to central nervous system drugs, and therefore warrant further development as therapeutics for the treatment of neurodegenerative diseases. 相似文献
74.
Krzysztof Szwed Wojciech Pawliszak Magdalena Szwed Marta Tomaszewska Lech Anisimowicz Alina Borkowska 《The Journal of thoracic and cardiovascular surgery》2021,161(4):1275-1282.e4
BackgroundNeuropsychiatric complications of surgical coronary revascularization are inconspicuous but frequent and clinically relevant. So far, attempts to reduce their occurrence, such as the introduction of off-pump coronary artery bypass (OPCAB) grafting method, have not brought the desired results. The aim of this trial was to determine whether using any of the 2 selected modifications of OPCAB could decrease the incidence of these undesired sequelae.MethodsIn this single-center, assessor- and patient-blinded, superiority, randomized controlled trial, 192 patients scheduled for elective isolated OPCAB were randomized to 3 parallel arms. The control arm underwent “conventional” OPCAB with vein grafts. The first study arm underwent anaortic OPCAB (ANA) with total arterial revascularization. The second study arm underwent OPCAB with vein grafts using carbon dioxide surgical field flooding (CO2FF). Outcomes included the incidence of postoperative delirium (PD) and early postoperative cognitive dysfunction (ePOCD).ResultsThe incidence of PD was 35.9% in the control (OPCAB) arm, 32.8% in the CO2FF arm, and 12.5% in the ANA arm (χ2 [2, N = 191] = 10.17; P = .006). Post hoc tests revealed that the incidence of PD in the ANA arm differed from that in the OPCAB arm (odds ratio [OR], 0.26; 95% confidence interval [CI], 0.09-0.68; P = .002). The incidence of ePOCD was 34.4% in the OPCAB arm, 28.1% in the CO2FF arm, and 9.5% in the ANA arm (χ2 [2, N = 191] = 11.58; P = .003). Post hoc tests revealed that the incidence of ePOCD differed between the ANA and OPCAB arms (OR, 0.20; 95% CI, 0.06-0.58; P < .001).ConclusionsPerforming ANA significantly decreases the incidence of PD and ePOCD compared with “conventional” OPCAB with vein grafts, whereas CO2FF is inconsequential in this regard. These results, which probably reflect decreased delivery of embolic load to the brain in ANA, may have practical applicability in daily practice to improve clinical outcomes. 相似文献
75.
仲伟军 《中国医院建筑与装备》2012,13(10):100-101
医院污水中不同程度地含有多种病毒、病菌、寄生虫卵和其他一些消毒剂、有机溶剂、酸、碱以及放射性等有毒有害物质。加强对医院产生的污水的控制和管理、提高医院污水处理的消毒效果是利国利民的事情,文中针对张家港市第一人民医院的新建工程,具体阐述了污水处理系统使用中的体会。 相似文献
76.
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78.
T. Stober J. L. Bermejo F. S. Schwindling M. Schmitter 《Journal of oral rehabilitation》2016,43(8):621-629
The purpose of this study was to measure enamel wear caused by antagonistic monolithic zirconia crowns and to compare this with enamel wear caused by contralateral natural antagonists. Twenty monolithic zirconia full molar crowns were placed in 20 patients. Patients with high activity of the masseter muscle at night (bruxism) were excluded. For analysis of wear, vinylpolysiloxane impressions were prepared after crown incorporation and at 6‐, 12‐, and 24‐month follow‐up. Wear of the occlusal contact areas of the crowns, of their natural antagonists, and of two contralateral natural antagonists (control teeth) was measured by use of plaster replicas and a 3D laser‐scanning device. Differences of wear between the zirconia crown antagonists and the control teeth were investigated by means of two‐sided paired Student's t‐tests and linear regression analysis. After 2 years, mean vertical loss was 46 μm for enamel opposed to zirconia, 19–26 μm for contralateral control teeth and 14 μm for zirconia crowns. Maximum vertical loss was 151 μm for enamel opposed to zirconia, 75–115 μm for control teeth and 60 μm for zirconia crowns. Statistical analysis revealed significant differences between wear of enamel by zirconia‐opposed teeth and by control teeth. Gender, which significantly affected wear, was identified as a possible confounder. Monolithic zirconia crowns generated more wear of opposed enamel than did natural teeth. Because of the greater wear caused by other dental ceramics, the use of monolithic zirconia crowns may be justified. 相似文献
79.
Orlando Oliveira de Morais érica Freitas Lima Lemos Márcia Carolline dos Santos Sousa Ciro Martins Gomes Izelda Maria Carvalho Costa Carmen Déa Ribeiro de Paula 《Anais brasileiros de dermatologia》2013,88(2):238-242
Melasma represents a pigmentary disorder that is difficult to treat. This study aims
to broadly review the use of ablative lasers (Er:YAG and CO2) in the treatment of
melasma, presenting the level of evidence of studies published to date. A total of 75
patients were enrolled in four case series studies (n=39), one controlled clinical
trial (n=6) and one randomized controlled clinical trial (n=30). Studies on the
Er:YAG laser showed better results with the use of short square-shaped pulses, which
determined low rates of post-inflammatory hyperpigmentation and long-lasting
maintenance of results. Likewise, studies on the CO2 laser proved the benefits of
short pulse duration along with low-density energy. Post-treatment maintenance with
the use of antipigmenting creams was necessary and effective to sustain long-term
results. Ablative lasers may represent another useful and effective tool against
melasma. Postinflammatory hyperpigmentation and difficulty in sustaining long-term
results still represent the main limitations to a broader use of ablative lasers.
Based on actual evidence, the use of this technology should be restricted to patients
with recalcitrant disease. Further studies will help establish optimal laser
parameters and treatment regimens. 相似文献
80.