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朱传磊  李永宸 《中国学校卫生》2022,43(11):1605-1608
俞凤宾是近代中国学校卫生先驱者中的重要一员。其学校卫生思想是运用近代学校卫生理论以解决中国学校卫生问题所做的初步尝试, 也是二者有机结合的产物。学校卫生的推行关系到国家强盛与国民健康, 是实施义务教育的先导; 能否处理好政府财政与学校卫生, 教师与学生、校医, 学校与家庭、视察员方面的关系, 是学校卫生工作成败的关键。  相似文献   
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Repaglinide and Metformin are used to treat Type 2 diabetes. Repaglinide with poor water solubility has relatively low oral bioavailability (56%) and undergoes hepatic first-pass metabolism. The oral bioavailability of metformin HCl is also low (about 50-60%). The purpose of this study was to prepare nanoemulsion formulations containing metformin HCl or repaglinide alone or in combination and characterize them in vitro and in vivo. Nanoemulsion formulations containing metformin HCl and/or repaglinide were successfully prepared and in vitro characterized. In addition, in vivo efficacy of nanoemulsion formulations was evaluated in a streptozotocin-nicotinamide-induced diabetic rat model. Biochemical, histopathological, and immunohistochemical evaluations were also performed. The mean droplet size and zeta potential values of nanoemulsion formulations were in the range of 110.15±2.64-120.23±2.16 nm and -21.95 – -24.33 mV, respectively. The percent entrapment efficiency values of nanoemulsion formulations were in the range of 93.600%-96.152%. All nanoemulsion formulations had a PDI of ≤0.223. A statistically significant decrease was observed in the blood glucose values of the diabetic rats treated with nanoemulsion formulations containing active substance/substances, compared to diabetic rats (control) (p<0.05). Nanoemulsion formulations (especially nanoemulsion containing metformin HCl and repaglinide combination) have a better antidiabetic activity and are more effective in reducing oxidative stress caused by diabetes.  相似文献   
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目的探讨ω-3多不饱和脂肪酸(ω-3 poly unsaturated fatty acids,ω-3 PUFAs)对慢性移植物抗宿主病(chronic graft versus host disease,cGVH)狼疮模型小鼠的免疫调节功能影响。方法单次腹腔注射bm12小鼠淋巴细胞建立cGVH小鼠模型,造模当天分别给予90%ω-3 PUFAs和97%EPA灌胃治疗,持续14 d。通过流式细胞术检测小鼠脾脏淋巴细胞中各免疫指标,ELISA检测小鼠血清中总IgG水平。结果与正常对照组相比,cGVH组明显下调Treg亚群,明显上调TFH细胞、生发中心B细胞和浆细胞亚群;与模型对照组相比,90%ω-3和97%EPA均明显上调Treg亚群,并明显下调TFH细胞、生发中心B细胞和浆细胞亚群;且97%EPA组小鼠血清中总IgG水平明显下降。结论在cGVH狼疮小鼠模型中,ω-3 PUFAs通过增加Treg细胞,减少TFH细胞、生发中心B细胞和浆细胞,抑制IgG的分泌,从而发挥免疫抑制作用,且其免疫抑制作用可能与ω-3 PUFAs含量相关。  相似文献   
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目的:探讨六味地黄汤对慢性抑郁大鼠记忆障碍的改善作用,并探讨其可能的作用机制。方法:Wistar雌性大鼠随机分为正常组(生理盐水)、慢性不可预见性温和应激(CUMS)模型组(生理盐水)、六味地黄汤低、中、高剂量组(2. 60,7. 81,23. 50 g·kg~(-1)·d~(-1))。除正常组外,其余各组造成CUMS模型。每周称体质量,观察其行为学指标变化;实时荧光定量聚合酶链式反应(Real-time PCR)检测其海马G蛋白偶联雌激素受体(GPR30),胞内磷脂酰肌醇激酶(PI3K),环磷酸腺苷反应元件结合蛋白(CREB),脑源性神经营养因子(BDNF) mRNA的表达;酶联免疫吸附测定(ELISA)检测血清中雌激素含量。结果:与正常组比较,模型组体质量、活动能力、兴趣等明显降低(P 0. 05,P 0. 01);与模型组比较,六味地黄汤2. 60,7. 81,23. 50 g·kg~(-1)可明显提高CUMS大鼠糖水偏好度(P 0. 01)和旷场实验的站立次数(P 0. 01);7. 81,23. 50 g·kg~(-1)明显提高旷场实验的总距离(P 0. 05,P 0. 01);2. 60,7. 81 g·kg~(-1)可缩短水迷宫实验寻台潜伏期(P 0. 01);7. 81 g·kg~(-1)可增加血清中雌激素含量(P 0. 05);CUMS模型组大鼠海马组织内的GPR30,PI3K,CREB,BDNF mRNA表达明显下降(P 0. 05,P 0. 01),六味地黄汤2. 60 g·kg~(-1)显著增加海马组织内的GPR30,CREB mRNA表达(P 0. 05,P 0. 01),7. 81 g·kg~(-1)明显增加海马组织内的GPR30,PI3K,CREB,BDNF mRNA表达量(P 0. 05,P 0. 01)。结论:六味地黄汤具有抗抑郁作用,逆转CUMS大鼠抑郁样行为及学习记忆障碍,其中中剂量组药效最显著。其作用机制可能与增加血清中雌激素和提高大鼠海马GPR30,PI3K,CREB,BDNF mRNA表达有关。  相似文献   
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目的:采用黄芪多糖(APS)与放射治疗(IR)联用,研究APS对人鼻咽癌CNE-1细胞的放疗敏感性及上皮间质转化(EMT)的作用机制。方法:采用细胞计数(CCK-8)法检测不同质量浓度APS(0,6.25,12.5,25,50,100,200 g·L-1)对CNE-1细胞的细胞毒性;克隆形成实验计算12.5 g·L-1APS与不同放射剂量(0,2,4,6 Gy)联用后对CNE-1细胞的存活分数(SF),利用线性二次方程数学模型(LQ)根据SF值绘制放射敏感曲线;细胞划痕和transwell小室实验分别检测各组细胞的迁移和侵袭能力;流式细胞仪检测各组细胞的凋亡情况;蛋白免疫印迹法(Western blot)检测各组细胞的EMT标记物、凋亡标记物以及蛋白激酶B/细胞外调节蛋白激酶(Akt/ERK)通路蛋白的表达水平。结果:克隆形成实验和放射敏感曲线结果表明,非毒性剂量12.5 g·L-1APS与4 Gy放射剂量联合给药可以明显增加CNE-1细胞的放疗敏感性;与空白组及IR组比较,APS与IR联用可以抑制CNE-1细胞的迁移和侵袭能力(P0.05),明显增加CNE-1细胞的凋亡率(P0.05)。与空白组及IR组比较,APS与IR联用可以显著下调间质型钙黏蛋白(N-cadherin),p-Akt和p-ERK蛋白表达水平,明显上调上皮型钙黏蛋白(E-cadherin),B淋巴细胞瘤-2相关X蛋白(Bax)和半胱天冬氨酸蛋白酶-3(Caspase-3)蛋白表达水平(P0.05)。结论:APS与IR联用可以抑制CNE-1细胞的迁移和侵袭,增加放疗引起的细胞凋亡,其可能通过抑制EMT和Akt/ERK通路有关。  相似文献   
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ObjectiveTo explore whether auricular concha eletroacupuncture (ACEA) is effective in regulating lipid-lipoprotein metabolism in rats submitted to cold stress.MethodsThirty-six adult male Sprague–Dawley rats were placed in four groups(9 rats in each group), the rats in three groups of which were submitted to cold stress for fourteen days, the last one of which was a control group. After the cold stress process, in those three groups, the rats of one group were with no treatment (stress only), two were treated with either ACEA or auricular margin eletroacupuncture (AMEA) repeated for fourteen days. On the 14th day, all the rats were sacrificed after all experimental procedure for blood sampling. Blood glucose, triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) levels were tested by using the collected serum. Plasma lecithin-cholesterol acyltransferase (LCAT) was measured with ELISA kit.ResultsACEA down-regulated the TG level (P < 0.05) and LDL-C level (P < 0.05), and up-regulated HDL-C level (P < 0.05) and LACT level (P < 0.05). AMEA did not regulate the bio-markers.ConclusionACEA played an important role in regulating lipid-lipoprotein metabolism in rats submitted to cold stress.  相似文献   
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《药学学报(英文版)》2020,10(2):327-343
Our recent studies demonstrated that the natural product nobiletin (NOB) served as a promising multidrug resistance (MDR) reversal agent and improved the effectiveness of cancer chemotherapy in vitro. However, low aqueous solubility and difficulty in total synthesis limited its application as a therapeutic agent. To tackle these challenges, NOB was synthesized in a high yield by a concise route of six steps and fourteen derivatives were synthesized with remarkable solubility and efficacy. All the compounds showed improved sensitivity to paclitaxel (PTX) in P-glycoprotein (P-gp) overexpressing MDR cancer cells. Among them, compound 29d exhibited water solubility 280-fold higher than NOB. A drug-resistance A549/T xenograft model showed that 29d, at a dose of 50 mg/kg co-administered with PTX (15 mg/kg), inhibited tumor growth more effective than NOB and remarkably increased PTX concentration in the tumors via P-gp inhibition. Moreover, Western blot experiments revealed that 29d inhibited expression of NRF2, phosphorylated ERK and AKT in MDR cancer cells, thus implying 29d of multiple mechanisms to reverse MDR in lung cancer.  相似文献   
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