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71.
72.
目的研究掌叶半夏超临界CO2乙醇萃取物(SEE-CO2 PP)对青霉素诱发惊厥的对抗作用。方法采用大鼠皮质局部定位注射青霉素诱发惊厥模型,研究SEE-CO2 PP对惊厥发作的潜伏期以及惊厥行为变化的影响,并用RM6240C型多道生理信号采集处理仪记录皮质和海马痫性放电的潜伏期、频率和痫波最高发放波幅,同时应用高效液相色谱法测定海马谷氨酸(Glu)、天冬氨酸(Asp)、甘氨酸(Gly)和γ-氨基丁酸(GABA)递质的含量。结果 SEE-CO2 PP 15和30 g·kg-1(ig)可延长青霉素诱发惊厥的潜伏期,并减弱发作强度。SEE-CO2PP能够延长痫性放电的潜伏期,减少痫性放电的频率,减小皮质和海马发放痫波的最高波幅,同时,SEE-CO2PP可以增加海马GABA的水平,对Gly,Asp和Glu水平无明显影响。结论 SEE-CO2PP可对抗青霉素诱发的惊厥行为和痫样放电,具有抗惊厥作用。  相似文献   
73.
乌索酸诱导K562/DNR细胞凋亡的实验研究   总被引:2,自引:0,他引:2  
目的通过体外细胞实验,证实乌索酸对柔红霉素(DNR)诱导的K562耐药细胞株(K562/DNR)有细胞毒和诱导凋亡作用,并摸索出作用的最佳浓度和时间,为乌索酸治疗血液系统恶性肿瘤奠定理论基础。方法利用WST-8分析,研究不同浓度和作用时间的乌索酸对K562/DNR细胞的体外细胞毒作用情况;利用流式细胞仪技术,研究不同浓度和作用时间的乌索酸诱导K562/DNR细胞凋亡的情况。结果乌索酸对K562/DNR细胞增殖具有明显抑制作用,诱导凋亡作用亦显著,并呈现一定的时间、浓度依赖性。结论乌索酸对于K562/DNR细胞具有确切的抗肿瘤活性。  相似文献   
74.
Obesity may cause metabolic syndrome and has become a global public health problem, and dietary fibers (DF) could alleviate obesity and metabolic syndrome by regulating intestinal microbiota. We developed a functional fiber (FF) with a synthetic mixture of polysaccharides, high viscosity, water-binding capacity, swelling capacity, and fermentability. This study aimed to investigate the effect of FF on obesity and to determine its prevention of obesity by modulating the gut microbiota. Physiological, histological, and biochemical parameters, and gut microbiota composition were investigated in the following six groups: control group (Con), high-fat diet group (HFD), low-fat diet group (LFD, conversion of HFD to LFD), high-fat +8% FF group (8% FF), high-fat +12% FF group (12% FF), and high-fat +12% FF + antibiotic group (12% FF + AB). The results demonstrated that 12% FF could promote a reduction in body weight and epididymal adipocyte area, augment insulin sensitivity, and stimulate heat production from brown adipose tissue (BAT) (p < 0.05). Compared with the HFD, 12% FF could also significantly improve the intestinal morphological integrity, attenuate systemic inflammation, promote intestinal microbiota homeostasis, and stabilize the production of short-chain fatty acids (SCFAs) (p < 0.05). Consistent with the results of 12% FF, the LFD could significantly reduce the body weight and epididymal adipocyte area relative to the HFD (p < 0.05), but the LFD and HFD showed no significant difference (p > 0.05) in the level of inflammation and SCFAs. Meanwhile, 12% FF supplementation showed an increase (p < 0.05) in the abundance of the Bifidobacterium, Lactococcus, and Coprococcus genus in the intestine, which had a negative correlation with obesity and insulin resistance. Additionally, the treatment with antibiotics (12% FF + AB) could inhibit the effect of FF in the HFD. The Kyoto Encyclopedia of Genes and Genomes (KEGG) function prediction revealed that 12% FF could significantly inhibit the cyanogenic amino acid metabolic pathway and decrease the serum succinate concentration relative to the HFD group. The overall results indicate that 12% FF has the potential to reduce obesity through the beneficial regulation of the gut microbiota and metabolites.  相似文献   
75.
目的研究心率变异性(HRV)与围绝经期综合征中医辨证分型的关系,探索中医证的客观化。方法通过对87例围绝经期综合征患者与32例正常对照组HRV的频域分析,观察、分析肝肾阴虚型、阴虚阳亢型、气阴两虚型围绝经期综合征与正常对照组HRV各指标的差异。结果围绝经期综合征患者三型之间TP、VLF、LF的差异显著,总的趋势从肝肾阴虚型、阴虚阳亢型、气阴两虚型依次降低(P<0.05,P<0.01);气阴两虚型较其他两型TP、VLF、LF、HF、LF/HF比值、VLF/HF比值、SD、LFnorm降低,HF、HFnorm升高,差异显著(P<0.05,P<0.01);肝肾阴虚型与正常对照组间HRV差异不显著(P>0.05);结论HRV的部分指标可能为围绝经期综合征中医辨证分型的客观化提供参考。  相似文献   
76.
Rationale:Femtosecond laser-assisted cataract surgery (FLACS) has grown in popularity among ophthalmologists as a novel surgical technique. However, malignant glaucoma (MG) is a complication of FLACS. Herein, we report a case of MG following FLACS.Patient concerns:A 66-year-old woman presented with complaints of blurred vision in the right eye and a foreign body sensation in both eyes. Ophthalmological examinations showed that the corrected distance visual acuity was 20/50 and 20/25 in the right and left eyes, respectively. Without any topical anti-glaucoma medication, the intraocular pressure (IOP) was 20 mmHg in the right eye and 17 mmHg in the left eye. Slit-lamp examination of the right eye revealed a transparent cornea with a defect in the punctate overlying epithelium; the central anterior chamber depth was shallow the peripheral iris laser shot was visible, the pupil was normal, and the lens was mainly cortical opacified.Diagnoses:Based on the patient''s symptoms, examination results, and preliminary diagnoses, age-related cataract in the right eye, binocular post-antiglaucoma surgery, pseudophakicin in the left eye, and Sjogren syndrome were included.Interventions:FLACS was performed to facilitate anterior capsulotomy and segmentation of the nucleus in the right eye. MG occurred after the femtosecond procedure, and with the treatment of medicines combined with phacoemulsification, IOP was eventually normal without further antiglaucoma therapy.Outcomes:IOP was 16 mmHg on postoperative day 1. Ocular ultrasonography revealed no choroid detachment or hemorrhage in the right eye. Two weeks postoperatively, uncorrected visual acuity was 20/25, and IOP remained normal with no further antiglaucoma treatment on 1 month postoperatively.Conclusions:We describe the occurrence of MG after FLACS and illustrate that miosis and bubble formation after FLACS may be risk factors for MG during FLACS.  相似文献   
77.
BackgroundEndometrial stromal tumours are uncommon tumours of the uterus. They mainly occur in perimenopausal women. Tumours with typical clinicopathological features do not usually pose diagnostic problems. However, rare clinicopathological features can occur, and clinicians without significant experience may have difficulty diagnosing these tumours and managing these patients.MethodsHerein, we report a case of endometrial stromal sarcoma that occurred in a 25‐year‐old woman. The pathological features, immunophenotype, treatment and prognosis were discussed.ResultsThe tumour revealed morphological heterogeneity, and there were similar proliferative‐type endometrial stromal cells, an extensive amount of mature adipose tissue, and prominent rhabdomyoblastic and smooth muscle cells. Histopathological and immunohistochemical studies confirmed low‐grade endometrial stromal sarcoma with smooth muscle, adipocytic and rhabdomyoblastic differentiation (approximately 60% were differentiated tissues). The final treatment of the tumour was total abdominal hysterectomy with bilateral salpingo‐oophorectomy. There was no evidence of recurrence for 109 months postoperatively.ConclusionsWe found that low‐grade endometrial stromal tumours with extensive adipocytic and prominent rhabdomyoblastic differentiation are misdiagnosed because they are infrequent. They must be differentiated from rhabdomyosarcoma with accurate identification of adipocytes, and long‐term follow‐up is needed.  相似文献   
78.
目的:观察前体脂质体型猪肺表面活性物质(PPPS)对整肺灌洗兔呼吸窘迫模型的治疗作用.方法:将PPPS水化后,经气管滴入治疗整肺灌洗型成年兔呼吸窘迫模型,观察兔的生命体征、血气、动态肺顺应性等指标的变化.结果:整肺灌洗后模型兔的血气pH、PaO2急剧下降,PaCO2轻度上升,心率明显减慢而呼吸频率增加,SBP和DBP均明显下降;支气管肺泡灌洗液中PS含量明显下降;病理检查提示出现肺出血、肺不张、肺泡萎缩、透明膜形成等病变,符合Ⅰ型重症呼吸衰竭临床诊断标准.经气管滴入PPPS后,可以使RDS模型兔的各项指标(pH、PaO2、PaCO2、HR、BR、SBP、DBP)明显改善,肺部的病理改变也明显减轻.统计学分析结果提示,治疗组和对照组pH(F=4.572,P=0.046)、PaO2(F=557.586,P=0.000)、PaCO2(F=96.798,P=0.000)、TV(F=117.851,P=0.000)、Cydn(F=276.996,P=0.000)、HR(F=34.975,P=0.000)、BR(F=28.167,P=0.000)、SBP(F=124.751,P=0.000)和DBP(F=108.672,P=0.000)比较差异均有统计学意义;在治疗组中,各个时间点的pH、PaO2、PaCO2、TV、Cydn、HR、BR、SBP和DBP比较差异均有统计学意义.结论:PPPS对实验性PS缺乏和肺损伤造成的呼吸窘迫有显著的治疗作用.  相似文献   
79.
目的 观察新生儿暂时性呼吸困难的肺部超声特点。方法 选取2018年7月至2019年6月扬州大学医学院附属淮安市妇幼保健院收治的60例暂时性呼吸困难患儿作为观察组,选取同期60例胎龄相近的健康新生儿作为对照组。观察组患儿分别在出生后6 h内和72 h后进行肺部超声检查,对照组患儿仅在出生后6 h内进行肺部超声检查,分析其肺部超声特点。结果 超声检查发现,所有患儿均无实变发生。出生后6 h内,观察组患儿胸膜线异常、A-线消失、存在B-线、肺泡间质综合征、双肺点和胸腔积液的发生率高于对照组,差异有统计学意义(P<0.05)。观察组出生后72 h后患儿胸膜线异常、A-线消失、存在B-线、肺泡间质综合征、双肺点和胸腔积液的发生率低于出生后6 h内超声检查结果,差异有统计学意义(P<0.05)。结论 暂时性呼吸困难患儿具有胸膜线异常、A-线消失、存在B-线、肺泡间质综合征、双肺点、无实变发生和胸腔积液等特点,肺部超声对新生儿暂时性呼吸困难的早期诊断和病情监测具有重要价值。  相似文献   
80.
ContextThe extracts of Aspongopus chinensis Dallas (Pentatomidae), an insect used in traditional Chinese medicine, have a complex chemical composition and possess multiple pharmacological activities.ObjectiveThis study comprehensively characterizes the chemical constituents of A. chinensis by an integrated targeted and untargeted strategy using UPLC-QTOF-MS combined with molecular networking.Materials and methodsThe ultra-performance liquid chromatography-tandem quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) combined with molecular networking-based dereplication was proposed to facilitate the identification of the chemical constituents of aqueous and ethanol extracts of A. chinensis. The overall strategy was designed to avoid the inefficiency and costliness of traditional techniques. The targeted compounds discovered in the A. chinensis extracts were identified by searching a self-built database, including fragment ions, precursor ion mass, and other structural information. The untargeted compounds were identified by analyzing the relationship between different categories, fragmentation pathways, mass spectrometry data, and the structure of the same cluster of nodes within the molecular network. The untargeted strategy was verified using commercial standard samples under the same mass spectrometry conditions.ResultsThe proposed integrated targeted and untargeted strategy was successfully applied to the comprehensive profiling of the chemical constituents of aqueous and ethanol extracts of A. chinensis. A total of 124 compounds such as fatty acids, nucleosides, amino acids, and peptides, including 74 compounds that were reported for the first time, were identified in this study.ConclusionsThe integrated strategy using LC tandem HRMS combined with molecular networking could be popularised for the comprehensive profiling of chemical constituents of other traditional insect medicines.  相似文献   
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