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81.
目的 探讨清热理气冲剂对实验性胆汁反流性胃炎(BRG)大鼠血浆内皮素(ET)和降钙素基因相关肽(CGRP)的影响。方法 60只大鼠随机分为A组(中药等效剂量组),B组(中药大剂量组),C组(西沙必利等效剂量组),D组(枸橼酸铋钾等效剂量组),E组(病理对照组)和F组(正常对照组)。除F组外,其余各组大鼠应用胆汁灌胃导致胃黏膜损害。2W后分别应用清热理气冲剂等效剂量、大剂量、西沙必利、枸橼酸铋钾处理。实验第4周观察胆汁反流性胃炎胃黏膜病理形态和应用放免法测定血浆ET和CGRP含量。结果 F组可见黏膜下层充血水肿,胃小凹增生,肠上皮化生,炎性细胞浸润等,而A组和B组胃黏膜组织形态显著改善。F组电镜观察到胃黏膜细胞问的紧密连接受损,线粒体肿胀,粗面内质网扩张,微绒毛变短或丢失,A组和B组的超微结构明显的改善。A组和B组血浆ET明显低于E组(P〈0.01)。A组和B组血浆CGRP明显高于E组(P〈0.01)。结论 清热理气冲剂可以减轻胃黏膜损伤,通过影响血浆ET和CGRP相关肽含量而达到治疗BRG目的。 相似文献
82.
目的分析裸花紫珠颗粒联合替硝唑氯化钠注射液、头孢呋辛钠抗菌药物治疗慢性盆腔炎(CPID)患者的临床效果。方法选取2017年1月~2018年12月某院CPID患者126例,随机分为研究组(n=63)与对照组(n=63),对照组予以替硝唑氯化钠注射液、头孢呋辛钠治疗,研究组在对照组基础上加用裸花紫珠颗粒。对比两组疗效、临床症状改善时间(发热、白带异常、下腹痛)及治疗前后血清炎性因子水平[白细胞介素-1β(IL-1β)、单核细胞趋化蛋白-1(MCP-1)]变化。结果研究组总有效率92.06%(58/63)较对照组79.37%(50/63)高(P<0.05);研究组发热、白带异常、下腹痛改善时间较对照组短(P<0.05);治疗后,研究组血清IL-1β、MCP-1水平较对照组低(P<0.05)。结论裸花紫珠颗粒联合替硝唑氯化钠注射液、头孢呋辛钠抗菌药物治疗CPID患者效果显著,可减轻炎症反应,改善患者临床症状。 相似文献
83.
《Ultrastructural pathology》2013,37(2):131-138
Two cases of small cell “undifferentiated” carcinoma (oat cell carcinoma) of the lung with dual neurosecretory and squamous differentiation are reported. One was treated with various regimens of chemotherapy and radiotherapy; the other was untreated at the time of biopsy. By electron microscopy, the same tumor cells showed membrane-bound, dense-core, neurosecretory-type granules and bundles of tonofibrils denoting squamous differentiation. This dual differentiation underlies the difficulty of ascribing an exclusively neural histogenesis to small cell carcinomas with neurosecretory-type granules. It is possible that entoderm-associated neuroectodermal tumors develop features of autochthonous entodermal tumors as a result of microenvironmental influences. An alternative hypothesis would be that small cell tumors are derived from basal reserve bronchoepithelial cells with pluripotentialities. 相似文献
84.
《Ultrastructural pathology》2013,37(3-4):279-286
Classically, ultrastructural examination of alveolar soft part sarcoma reveals large, dramatic, rhomboid to needlelike crystals with a characteristic substructure. In this study of four cases of alveolar soft part sarcoma, only two exhibited large crystals, which were rare. All four cases, however, exhibited round, electron-dense granules, and in the two cases without large crystals these granules rarely exhibited elongation with the characteristic substructure of alveolar soft part sarcoma that permits definitive diagnosis. Two of these cases had been previously studied at other institutions, where crystals were not identified ultrastructurally and electron microscopy was considered noncontributory. Large crystals, then, may be rare or absent in alveolar soft part sarcoma. Careful search may be necessary to find granules with the characteristic periodic substructure. 相似文献
85.
86.
Paclitaxel-induced stress granules increase LINE-1 mRNA stability to promote drug resistance in breast cancer cells 下载免费PDF全文
Xiao Shi Xinxin Si Ershao Zhang Ruochen Zang Nan Yang He Cheng Zhihong Zhang Beijing Pan Yujie Sun 《生物医学研究杂志》2021,35(6):411-424
Abnormal expression of long interspersed element-1 (LINE-1) has been implicated in drug resistance, while our previous study showed that chemotherapy drug paclitaxel (PTX) increased LINE-1 level with unknown mechanism. Bioinformatics analysis suggested the regulation of LINE-1 mRNA by drug-induced stress granules (SGs). This study aimed to explore whether and how SGs are involved in drug-induced LINE-1 increase and thereby promotes drug resistance of triple negative breast cancer (TNBC) cells. We demonstrated that SGs increased LINE-1 expression by recruiting and stabilizing LINE-1 mRNA under drug stress, thereby adapting TNBC cells to chemotherapy drugs. Moreover, LINE-1 inhibitor efavirenz (EFV) could inhibit drug-induced SG to destabilize LINE-1. Our study provides the first evidence of the regulation of LINE-1 by SGs that could be an important survival mechanism for cancer cells exposed to chemotherapy drugs. The findings provide a useful clue for developing new chemotherapeutic strategies against TNBCs. 相似文献
87.
目的探讨养胃颗粒联合四联抗菌法治疗Hp阳性慢性胃炎的疗效及其安全性。方法选取2018年12月至2019年12月Hp相关性慢性胃炎患者120例,按照随机数字法分为对照组和观察组,各60例。对照组给予四联疗法,观察组给予养胃颗粒联合四联疗法,比较两组患者治疗有效率、Hp根除率、血液指标变化及不良反应情况。结果观察组临床治疗总有效率、Hp根除率、血清GAS水平、血清PGⅠ水平和PGⅠ/PGⅡ比值均高于对照组,差异有统计学意义(P<0.05)。结论养胃颗粒联合四联抗菌法治疗Hp阳性慢性胃炎的临床效果更优越,能显著提高Hp根除率,并可以减少消化道不良反应和肝损病例。 相似文献
88.
目的 研究复方芪苓配方颗粒对高尿酸血症大鼠的降尿酸作用,并从尿酸排泄途径探讨其作用机制。方法 SD大鼠随机分为正常组、模型组、苯溴马隆组、复方芪苓配方颗粒高、中、低剂量组(9.6,4.8,2.4 g·kg-1),通过腺嘌呤灌胃及氧嗪酸钾皮下注射建立高尿酸血症模型,连续给药14 d。分别测定血清尿酸、肌酐、尿素、尿尿酸水平,计算肾脏尿酸清除率。采用RT-PCR方法分别测定动物肾脏中相关转运体的表达水平;观察肾组织病理改变。结果 与模型组比较,复方芪苓配方颗粒组高尿酸血症大鼠的血清尿酸、肌酐、尿素水平显著降低,其肾脏尿酸清除率显著升高;其肾组织病理改变显示,肾小管内尿酸盐结晶减少,肾小管-间质损伤较轻。复方芪苓配方颗粒可以显著下调肾脏尿酸盐转运体1(URAT1)、葡萄糖转运蛋白9(GLUT9) mRNA的表达,上调有机阴离子转运体1(OAT1) mRNA的表达。结论 复方芪苓配方颗粒能降低高尿酸血症大鼠的血清尿酸水平并减轻肾组织病理损害,其作用机制可能是通过调节尿酸转运体的表达水平,以降低肾脏尿酸盐重吸收能力、增加尿酸盐分泌,从而促进尿酸排泄。 相似文献
89.
Okamoto M Ohara-Imaizumi M Kubota N Hashimoto S Eto K Kanno T Kubota T Wakui M Nagai R Noda M Nagamatsu S Kadowaki T 《Diabetologia》2008,51(5):827-835
Aims/hypothesis A decrease in plasma adiponectin levels has been shown to contribute to the development of diabetes. However, it remains uncertain
whether adiponectin plays a role in the regulation of insulin secretion. In this study, we investigated whether adiponectin
may be involved in the regulation of insulin secretion in vivo and in vitro.
Methods The effect of adiponectin on insulin secretion was measured in vitro and in vivo, along with the effects of adiponectin on
ATP generation, membrane potentials, Ca2+ currents, cytosolic calcium concentration and state of 5′-AMP-activated protein kinase (AMPK). In addition, insulin granule
transport was measured by membrane capacitance and total internal reflection fluorescence (TIRF) analysis.
Results Adiponectin significantly stimulated insulin secretion from pancreatic islets to approximately 2.3-fold the baseline value
in the presence of a glucose concentration of 5.6 mmol/l. Although adiponectin had no effect on ATP generation, membrane potentials,
Ca2+ currents, cytosolic calcium concentrations or activation status of AMPK, it caused a significant increase of membrane capacitance
to approximately 2.3-fold the baseline value. TIRF analysis revealed that adiponectin induced a significant increase in the
number of fusion events in mouse pancreatic beta cells under 5.6 mmol/l glucose loading, without affecting the status of previously
docked granules. Moreover, intravenous injection of adiponectin significantly increased insulin secretion to approximately
1.6-fold of baseline in C57BL/6 mice.
Conclusions/interpretation The above results indicate that adiponectin induces insulin secretion in vitro and in vivo.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorised users.
M. Okamoto and M. Ohara-Imaizumi contributed equally to this study. 相似文献
90.
目的观察托伐普坦联合尿毒清颗粒治疗肾病综合征患者的临床效果。方法选择2017年8月-2018年12月四川省资阳市第一人民医院肾病内科诊治肾病综合征患者90例作为研究对象,依据随机数字表法将患者分为对照组(n=45)和观察组(n=45),入院后根据诊疗规范进行治疗,对照组给予托伐普坦,观察组在对照组基础上给予尿毒清颗粒,治疗1个月后,比较2组治疗前后的血肌酐、尿素氮、尿量、血红蛋白、血清白蛋白、钾离子和钙离子水平,记录不良反应发生情况。结果治疗1个月后,2组血肌酐与尿素氮水平均降低,且观察组降低幅度大于对照组(t/P=3.999/0.000、2.316/0.023);2组的尿量、血红蛋白和血清白蛋白均上升,且观察组上升幅度大于对照组(t/P=-11.320/0.000、-4.606/0.000、-3.068/0.003),2组治疗前后的钾、钙离子浓度均未发生明显变化(P>0.05);不良反应发生率比较差异亦无统计学意义(P>0.05)。结论使用托伐普坦联合尿毒清颗粒治疗肾病综合征患者,可以改善患者的肾功能,改善尿量和营养状态,稳定体内电解质水平,安全性良好。 相似文献