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101.
目的研究丹蛭降糖胶囊对糖尿病肾病大鼠的肾脏病理改变和足细胞自噬水平的影响,初步探讨其相应的作用机制。方法选取GK大鼠40只,采用醋酸脱氧皮质酮-盐皮下注射联合高脂饲料喂养诱导糖尿病肾病模型。造模成功后随机分为模型组、丹蛭降糖胶囊低剂量组[0.54 g/(kg·d)]、高剂量组[1.08 g/(kg·d)]、缬沙坦组[10 mg/(kg·d)],每组10只。另选取10只同周龄正常Wistar大鼠作为正常组。模型组和正常组给予等容积生理盐水。连续灌胃10周后检测空腹血糖(FBG)、血肌酐(SCr)、尿素氮(BUN)和尿微量蛋白(U-mAlb)。Western Blot检测肾小球p-mTOR、p-S6K1、Beclin-1、LC3和Nephrin蛋白的表达,HE染色和PAS染色后于光镜下观察肾脏病理变化,电镜下观察各组亚细胞形态结构变化。结果与正常组比较,模型组FBG、SCr、BUN、U-mAlb水平升高(P<0.01);与模型组比较,丹蛭降糖胶囊低、高剂量组和缬沙坦组U-mAlb水平降低(P<0.01)。模型组可见肾小球基底膜增厚,系膜基质沉积,足细胞损伤,各用药组均有不同程度改善,丹蛭降糖胶囊高剂量组足细胞内有较多自噬体形成。与正常组比较,模型组p-mTOR、p-S6K1的表达增高,Nephrin、Beclin-1和LC3的表达水平降低(P<0.01);与模型组比较,各用药组p-mTOR、p-S6K1的表达下降,Nephrin、Beclin-1和LC3的表达增高(P<0.01)。丹蛭降糖胶囊高剂量组和缬沙坦组Beclin1、LC3Ⅱ/LC3Ⅰ水平较丹蛭降糖胶囊低剂量组升高(P<0.05)。结论丹蛭降糖胶囊具有减轻糖尿病肾病大鼠U-mAIb、足细胞损伤及相关肾脏病理改变的作用,其机制可能与抑制mTOR/S6K1信号通路进而提高足细胞的自噬活性有关。  相似文献   
102.
Background: Nivolumab has been approved for use in advanced gastric cancer (GC) after third-line chemotherapy in Japan. However, it remains difficult to predict favorable nivolumab response before treatment. Methods: We evaluated the clinical course with a focus on the chronological changes in neutrophil/lymphocyte ratio (NLR) throughout the chemotherapy and assessed the relationship between nivolumab response and chronological changes in NLR before nivolumab administration. Results: We experienced nine cases who received nivolumab monotherapy for unresectable advanced or postoperative recurrent GC. Nivolumab was used as third-line chemotherapy in all patients, and partial response (PR) and stable disease (SD) were observed in two patients each. Nivolumab treatment resulted in progressive disease (PD) in five patients. In patients with PR or SD, changes in the NLR tended to correspond to the response of target metastatic lymph nodes to first- and second-line chemotherapy. In the four cases with PR or SD following nivolumab, ∆NLRresponses that was the difference in the degree of decline during the most effective pretreatment chemotherapy were 1.39, 0.73, 1.62, and 1.22. However, the patients with PD showed lower ∆NLRresponses, at 0.66, 0.66, 0.25, 0.13, and -0.05 in the five cases. Mean ∆NLRresponses in the patients with PR or SD and patients with PD were 1.17 and 0.33, respectively (P = 0.0008). Conclusions: We experienced nine GC cases treated with nivolumab and assessed the association between chronological NLR changes throughout chemotherapy and tumor response to nivolumab. Changes in NLR during pretreatment chemotherapy might predict tumor response to nivolumab monotherapy in patients with advanced GC.  相似文献   
103.
104.
The impact of primary hand osteoarthritis (HOA) on bone mass, microstructure, and biomechanics in the affected skeletal regions is largely unknown. HOA patients and healthy controls (HCs) underwent high-resolution peripheral quantitative computed tomography (HR-pQCT). We measured total, trabecular, and cortical volumetric bone mineral densities (vBMDs), microstructural attributes, and performed micro–finite element analysis for bone strength. Failure load and scaled multivariate outcome matrices from distal radius and second metacarpal (MCP2) head measurements were analyzed using multiple linear regression adjusting for age, sex, and functional status and reported as adjusted Z-score differences for total and direct effects. A total of 105 subjects were included (76 HC: 46 women, 30 men; 29 HOA: 23 women, six men). After adjustment, HOA was associated with significant changes in the multivariate outcome matrix from the MCP2 head (p < .001) (explained by an increase in cortical vBMD (Δz = 1.07, p = .02) and reduction in the trabecular vBMD (Δz = −0.07, p = .09). Distal radius analysis did not show an overall effect of HOA; however, there was a gender-study group interaction (p = .044) explained by reduced trabecular vBMD in males (Δz = −1.23, p = .02). HOA was associated with lower failure load (−514 N; 95%CI, −1018 to −9; p = 0.05) apparent in males after adjustment for functional status. HOA is associated with reduced trabecular and increased cortical vBMD in the MCP2 head and a reduction in radial trabecular vBMD and bone strength in males. Further investigations of gender-specific changes of bone architecture in HOA are warranted. © 2020 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research.  相似文献   
105.
《中国现代医生》2020,58(14):5-8
目的研究经导管动脉化疗栓塞(TACE)对原发性肝癌患者的疗效及中性粒细胞/淋巴细胞计数比(NLR)、血小板/淋巴细胞计数比(PLR)的影响。方法选择2015年6月~2019年1月我院接诊的原发性肝癌患者80例作为研究对象,采用随机数表法将患者分为两组,每组各40例。对照组予传统肝切除术治疗,观察组采用TACE治疗。对比两组治疗后的临床效果,NLR、PLR、癌胚抗原(CEA)、可溶性B7-H4、可溶性白细胞介素-2受体(sIL-2R)及并发症发生情况。结果治疗后,两组患者的总有效率分别为75.00%和52.50%,观察组高于对照组,差异有统计学意义(P0.05);治疗前,两组患者NLR、PLR水平对比,差异无统计学意义(P0.05);治疗后,患者NLR、PLR水平下降,观察组低于对照组,差异有统计学意义(P0.05);治疗前,两组患者CEA、B7-H4、sIL-2R水平对比,差异无统计学意义(P0.05);治疗后,两组患者CEA、B7-H4、sIL-2R水平下降,观察组低于对照组,差异有统计学意义(P0.05);两组患者并发症发生率分别为17.50%、40.00%,观察组低于对照组,差异有统计学意义(P0.05)。结论在原发性肝癌患者中使用TACE效果显著,可有效改善患者肿瘤标志物水平,减少并发症,值得推广应用。  相似文献   
106.
107.
108.
目的:观察地黄饮子加减方对血管性痴呆模型大鼠学习记忆能力及海马CA1区神经元的影响。方法:将84只SD雄性大鼠,按随机原则选出12只大鼠作为假手术组,其余72只大鼠采用两血管阻断法制备血管性痴呆模型,筛选60只模型大鼠,每组12只,随机分为模型组,尼莫地平组(0. 011 g·kg~(-1)),地黄饮子加减方高、中、低(4. 54,2. 27,1. 14 g·kg~(-1))剂量组。连续灌胃30 d后,Morris水迷宫检测大鼠学习记忆能力,苏木素-伊红(HE)观察海马CA1区神经元形态结构改变,透射电镜观察海马CA1区神经元超微结构变化,原位细胞凋亡检测法(TUNEL)检测海马CA1区细胞凋亡水平,免疫组化(IHC)检测海马CA1区组织磷脂酰肌醇3-激酶(PI3K),蛋白激酶B(Akt),半胱氨酸蛋白酶-3(Caspase-3)表达水平。结果:与假手术组比较,模型组大鼠逃避潜伏期显著延长,穿越原平台次数显著减少(P 0. 01),海马CA1区神经元形态均有不同程度地损伤,凋亡率显著增加(P 0. 01),PI3K,Akt的积分吸光度和平均积分吸光度明显降低(P 0. 01),Caspase-3的积分吸光度和平均积分吸光度显著增高(P 0. 01);与模型组比较,各给药组大鼠逃避潜伏期缩短(P 0. 05,P 0. 01),穿越原平台次数增加(P 0. 05,P 0. 01),PI3K,Akt的积分吸光度和平均积分吸光度值显著增高(P 0. 01),Caspase-3的积分光密度和平均积分吸光度不同程度降低(P 0. 05,P 0. 01)。结论:地黄饮子加减方可改善血管性痴呆模型大鼠学习记忆能力和海马CA1区神经元损伤,潜在机制可能与PI3K/Akt信号转导途径的激活,抑制大鼠海马CA1区神经细胞的凋亡有关。  相似文献   
109.
目的 测定不同来源的4种大宗常用中药饮片中黄曲霉毒素(AFB1、AFB2、AFG1和AFG2)的含量,比较不同基质中药饮片中黄曲霉毒素的分布状况。方法 基于免疫亲和柱净化-高效液相色谱分离-荧光检测器(IAC-HPLC-FLD)方法,分析不同产地共75批中药样品。结果 柏子仁、薏苡仁、决明子及党参共计75批中药饮片中,阳性检出:26批柏子仁(AFs 1.22-46.67 μg·kg-1,AFB1 1.22-31.40 μg·kg-1)、4批薏苡仁(AFs 1.97-41.13 μg·kg-1,AFB1 1.97-36.40 μg·kg-1)、1批决明子(AFs 13.65 μg·kg-1,AFB1 12.60 μg·kg-1),阳性率41%,超标率15%。阳性样品经 LC-MS/MS确证,排除假阳性。4种大宗常用中药饮片柏子仁、薏苡仁、决明子、党参中黄曲霉毒素的污染水平依次降低,阳性检出率分别为77%、29%、7%、0%,表明中药材中黄曲霉毒素的污染状况与药材基质密切相关。结论 针对易污染AFs的中药品种,需进一步加强其污染状况的全面检测分析,为黄曲霉毒素的有效防控以及完善中药的质量标准提供科学依据,从而保障中药用药安全。  相似文献   
110.
Objective: To analyze the effect of sirolimus and sunitinib in blocking the tumor growth and to evaluate the expressions of estrogen receptor (ER), progesterone receptor (PgR), and human epidermal growth factor receptor-2 (HER2/neu) after treated with sirolimus and sunitinib. Methods: Thirty-two female Sprague Dawley rats at age 21-days old were administered intraperitoneally with N-Methyl-N-Nitroso Urea (NMU), dosed at 70mg/kg body weight. The rats were divided into 4 groups; Group 1 (Control, n=8), Group 2 (Sirolimus, n=8), Group 3 (Sunitinib, n=8) and Group 4 (Sirolimus+Sunitinib, n=8), being treated twice when the tumor reached the size of 14.5±0.5 mm and subsequently sacrificed after 5 days. The protein expressions of ER, PgR and HER2/neu of the tumor tissues were evaluated by using immunohistochemistry analysis. Results: Treatment with sirolimus alone lowered expressions of ER and PgR of breast cancer and reduced tumor size. There was no significant difference of ER and PgR expressions between control and sunitinib treated tumor. Sunitinib treated tumors reduce in diameter after the first treatment, however the diameter increases after the second treatment. Histologically, sunitinib treated tumor did not show any aggressive invasive carcinoma of no special type (NST) histological subtypes. In addition, all NMU-induced tumors are HER2/neu-negative scoring. Conclusion: Sirolimus is neither synergistic nor additive with sunitinib for breast cancer treatment.  相似文献   
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