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112.
目的 建立测定坎地沙坦酯氨氯地平片有关物质的高效液相色谱法。方法 采用Inertsil ODS-SP C18(150 mm× 4.6 mm,5 μm)色谱柱,以0.035 mol·L-1 KH2PO4(磷酸调pH 3.0)-甲醇-乙腈为流动相,梯度洗脱,检测波长238 nm,流速1.0 mL·min-1。结果 特异性杂质和破坏条件下产生的降解产物与主药分离较好,3批样品最大单个杂质为坎地沙坦酯杂质B,总杂质均〈0.5%。结论 本法专属性强,灵敏度高,重现性好,能够有效控制产品质量。 相似文献
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Yosef SHRIFI Ali FARAHNAK Abolfazle GOLESTANI Mohamad Reza ESHRAGHIAN Ashkan FARIDI Mohamad bagher MOLAEI RAD 《Iranian Journal of Parasitology》2014,9(1):107-113
Background
Fasciola hepatica is one of the most important helminthes parasites and triclabendazole (TCBZ) is routinely used for treatment of infected people and animals. Secreted protease enzymes by the F. hepatica plays a critical role in the invasion, migration, nutrition and the survival of parasite and are key targets for novel drugs and vaccines. The aim of study was to determine the protease activity of excretory- secretory products (ESP) of F. hepatica in the presence of TCBZ anthelmintic.Methods
F. hepatica helminthes were collected and cultured within RPMI 1640 [TCBZ treated (test) and untreated (control)] for 6 h at 37 °C. ESP of treated and control were collected, centrifuged and supernatants were stored at -20°C. Protein concentrations were measured according to Bradford method. Protease enzymes activities of ESP samples were estimated by using sigma’s non-specific protease activity assay. ESP protein bands were detected by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE).Results
Mean protein concentrations in control and treated of ESP samples were determined 196.1 ±14.52 and 376.4 ±28.20 μg/ml, respectively. Mean protease enzymes activities in control and treated were 0.37 ±0.1 and 0.089 ±0.03 U/ml, respectively. Significant difference between proteins concentrations and protease enzymes activities of two groups was observed (P<0.05). SDS-PAGE showed different patterns of protein bands between treated and control samples.Conclusion
The TCBZ reduced secreted protease enzymes activities and possibly effects on invasion, migration, nutrition and particularly survival of the parasite in the host tissues. 相似文献115.
116.
目的 了解中药生熟异用饮片在医院药房、零售药店与饮片加工企业的应用及管理情况,为加强监管提供参考.方法 采用问卷、访问和实地考察的形式进行调查.结果 生熟饮片功用及质量不同,临床必须严格分用.但是目前,中医药行业存在着生熟混用、饮片质量参差不齐、处方应付不规范等相关问题.结论 应提高医师和药师的业务水平,熟悉掌握生熟饮片的药效差异,做到对症下药,准确应用;在完善处方应付的同时,中医师也应学习中药炮制等相关知识,提倡“写全名”、“勿笼统”,以免贻误患者;饮片企业应从源头上控制中药材的质量,保证饮片生产的炮制工艺有据可依,提升中药饮片行业的现代化科技水平;政府部门应进一步加强监管,建立饮片质量分级管理机制,实施批准文号管理和统一炮制工艺,切实有效地提升饮片质量. 相似文献
117.
Government leaders have struggled to reduce the infection and deaths due to coronavirus disease 2019 (COVID-19) as well as to keep the economy and businesses open. There is a large variation of mortality and damage to economy among countries. One possible cause leading to the large variation is the manner in which countries have delt with COVID-19. Some countries or regions such as China, New Zealand, and Taiwan, acted quickly and aggressively by implemen ting border closures, lockdown, school closures, mass testing, etc. On the other hand, many European countries, United States, and Brazil delayed their decisions to implement these restrictions and measures. No study has assessed the correlation between gross domestic product (GDP) and COVID-19 mortality. In the present study, there was a negative correlation between GDP and COVID-19 mortality suggesting that countries that failed to control the virus (larger COVID-19 mortality) would see a larger decline in GDP. Governmental leaders should act fast and aggressively when making decisions because data shows that countries who have run after two hares have caught neither. Furthermore, citizens of each country need to do their own part by following guidelines and practicing social distancing and mask wearing, which are considered the most effective, easiest, and cheapest measures that can be taken, so that repeated lockdowns can be avoided. 相似文献
118.
Wei Zhang Yuan-Yuan Li Qing-Hua Shang Lin Qi Mi-Mi Sun Gang Chen Yong An Jing-Xin Li Wang-Ping Jia Zhong-An Sun Hui-Bin Xu Qing-Mei Gao Li Tang Xiao-Wen Wang Ji-Yuan Zhang Yi-Ming Mu Fu-Sheng Wang 《Annals of hepatology》2022,27(6):100745
Introduction and ObjectivesHepatitis B surface antigen (HBsAg) clearance, indicating functional cure or resolved chronic hepatitis B (CHB), remains difficult to achieve via nucleos(t)ide analogue monotherapy. We investigated whether metformin add-on therapy could help achieve this goal in entecavir-treated patients with hepatitis B e antigen (HBeAg)-negative CHB.Patients and MethodsPatients with HBeAg-negative CHB who met eligibility criteria (entecavir treatment for > 12 months, HBsAg < 1000 IU/mL) were randomly assigned (1:1) to receive 24 weeks of either metformin (1000 mg, oral, once a day) or placebo (oral, once a day) add-on therapy. The group allocation was blinded for both patients and investigators. Efficacy and safety analyses were based on the intention-to-treat set. The primary outcome, serum HBsAg level (IU/mL) at weeks 24 and 36, was analysed using mixed models.ResultsSixty eligible patients were randomly assigned to the metformin (n = 29) and placebo (n = 31) groups. There was no substantial between-group difference in the HBsAg level at week 24 (adjusted mean difference 0.05, 95% confidence interval -0.04 to 0.13, p = 0.278) or week 36 (0.06, -0.03 to 0.15, p = 0.187), and no significant effect of group-by-time interaction on the HBsAg level throughout the trial (p = 0.814). The occurrence of total adverse events between the two groups was comparable (9 [31.0%] of 29 vs. 5 [16.1%] of 31, p = 0.227) and no patient experienced serious adverse events during the study.ConclusionAlthough it was safe, metformin add-on therapy did not accelerate HBsAg clearance in entecavir-treated patients with HBeAg-negative CHB. 相似文献
119.
Cassandra D. M. Churchill Mariusz Klobukowski Jack A. Tuszynski 《Chemical biology & drug design》2015,86(2):190-199
Laulimalide, a cancer chemotherapeutic in preclinical development, has a unique binding site located on two adjacent β‐tubulin units between tubulin protofilaments of a microtubule. Our extended protein model more accurately mimics the microtubule environment, and together with a 135 ns molecular dynamics simulation, identifies a new binding mode for laulimalide, which differs from the modes presented in work using smaller protein models. The new laulimalide–residue interactions that are computationally revealed explain the contacts observed via independent mass shift perturbation experiments. The inclusion of explicit solvent shows that many laulimalide–tubulin interactions are water mediated. The new contacts between the drug and the microtubule structure not only improve our understanding of laulimalide binding but also will be essential for efficient derivatization and optimization of this prospective cancer chemotherapy agent. Observed changes in secondary protein structure implicate the S7–H9 loop (M–loop) and H1′–S2 loop in the mechanism by which laulimalide stabilizes microtubules to exert its cytotoxic effects. 相似文献
120.
Jeong Min Seong Chang Eun Park Mi Young Gi Ju Ae Cha Eun Young Jung Jun Ho Lee Hyun Ho Sung Seung Bum Yang Bae Lee Jae Heon Lim Hyun Yoon 《Primary Care Diabetes》2021,15(3):541-547
AimsThe present study assesses the relationship between uric acid (UA) and lipid accumulation product index (LAP) by gender among Korean adults.MethodsData from 5670 subjects (2463 men and 3207 women) in the Korean National Health and Nutrition Examination Survey (KNHANES VII-1) 2016 were analyzed. LAP was divided into four quartiles (Q1–Q4).ResultsThere were several key findings. Compared with Q1, in the overall population, the odds ratios (ORs) of hyperuricemia (UA ≥ 7.0 mg/dL in men or UA ≥ 6.0 mg/dL in women) were significantly higher in Q2 [1.847 (95% confidence interval [CI], 1.325–2.575)], Q3 [3.050 (95% CI, 2.216–4.198)], and Q4 of LAP [6.367 (95% CI, 4.658–8.704)]. In men, the ORs of hyperuricemia were significantly higher in Q2 [1.658 (95% CI, 1.162–2.367)], Q3 [2.341 (95% CI, 1.656–3.308)], and Q4 [4.633 (95% CI, 3.290–6.525)] than Q1. In women, the ORs of hyperuricemia were significantly higher in Q2 [2.254 (95% CI, 1.085–4.680)], Q3 [5.402 (95% CI, 2.735–10.668)], and Q4 [11.025 (95% CI, 5.620–21.628)] than Q1. In addition, UA levels were positively associated with LAP level in men (r = 0.218; p < 0.001), women (r = 0.261; p < 0.001), and the overall population (r = 0.260; p < 0.001).ConclusionsHyperuricemia was positively associated with LAP in Korean men and women. 相似文献