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131.
目的:研究卡介菌多糖核酸对豚鼠急性过敏反应的作用及可能的机制,探讨卡介菌多糖核酸的质量控制效力模型的提高方法。方法:建立牛血清白蛋白诱导豚鼠产生急性过敏反应模型。激发后30 min内观察豚鼠全身反应,并根据致敏性症状评分标准分级。取血用ELISA法测致敏前、攻击前及攻击后豚鼠血清总Ig E和组胺水平。结果:攻击后,模型组和卡介菌多糖核酸低剂量组豚鼠出现不同程度的急性过敏反应症状,而卡介菌中、高剂量组豚鼠急性过敏反应症状明显缓解。模型组在攻击前、后采集的血清总Ig E水平分别为1.637 0±0.158 6,1.683 1±0.228 1μg·ml-1,较正常对照组显著升高(P<0.01),而同时给予卡介菌多糖核酸后,卡介菌高剂量和中剂量处理组在攻击前、后采集的血清总Ig E水平与模型组比较均显著降低(P<0.01)。经牛血清蛋白致敏后,在攻击前后,模型组血清中组胺水平分别为1.499 7±0.133 1,1.512 1±0.050 6μg·ml-1,与阴性对照组相比均显著升高(P<0.01),而同时给予卡介菌多糖核酸后,卡介菌高、中、低各剂量处理组在攻击前、后采集的血清中组胺水平与模型组比较有明显降低(P<0.01)。结论:卡介菌多糖核酸可剂量依赖性抑制牛血清蛋白引起的急性过敏反应。其抗急性过敏反应的可能机制与降低血清总Ig E和组胺水平有关。  相似文献   
132.
摘 要 目的: 探讨清毒颗粒对二甲基苯蒽(DMBA)诱导SD大鼠乳腺癌的药效。方法: DMBA诱导大鼠乳腺癌,观察清毒颗粒对肿瘤抑制率,HE染色观察病理特点,IHC检测肿瘤组织Ki 67分布及含量,ELISA检测大鼠血清中IL-12、IFN-γ、IL-4和IL-10含量。结果: 低、中、高剂量清毒颗粒和柴胡皂苷a的抑瘤率分别为:30.93%,43.84%,44.17%和43.48%;清毒颗粒和柴胡皂苷a可显著降低Ki 67表达量;上调血清中IL-12、IFN-γ含量,下调IL-4、IL-10含量。结论: 清毒颗粒具有抗乳腺癌作用,其机制可能是调节机体免疫,增强抗肿瘤免疫作用。  相似文献   
133.
摘 要 目的: 观察巴马神酒对小鼠免疫功能、肝脏脂质过氧化损伤及游泳耐力的药理作用。方法: 采用碳粒廓清实验法及环磷酰胺致小鼠免疫低下模型评价巴马神酒对免疫功能的作用;建立四氯化碳致小鼠急性肝损伤模型,以血清中丙氨酸氨基转移酶(ALT)、天门冬氨酸转移酶(AST)、超氧化物歧化酶(SOD)以及丙二醛(MDA)的水平,评价巴马神酒抗肝脏脂质过氧化损伤作用;以小鼠负重游泳的持续时间,评价巴马神酒提高游泳耐力的功能。结果: 巴马神酒能提高小鼠吞噬指数K及吞噬系数α(与空白组比较,P<0.01或P<0.05);对环磷酰胺诱发的胸腺、脾脏脏器指数的下降有一定的提高(与模型组比较,P<0.05);能够降低四氯化碳致小鼠急性肝损伤血清中AST、ALT含量,降低血清MDA的含量,增强SOD的活性(与模型组比较,P<0.01或P<0.05);可以延长小鼠负重游泳时间(与空白组比较,P<0.01或P<0.05)。结论: 巴马神酒具有提升小鼠巨噬细胞吞噬能力、保护免疫低下小鼠的胸腺和脾脏指数的作用,并具有抗肝脏脂质过氧化损伤和提高游泳耐力的作用。  相似文献   
134.
Rationale:Intravenous leiomyomatosis (IVL) is a rare and special type of smooth muscle tumor originating in the uterus. It is classified as a benign disease according to its histological features but shows the behavioral characteristics of a malignant tumor. It is easily misdiagnosed and recurrent. The purpose of this study was to retrospectively analyze clinicopathological data of 25 cases of IVL in order to enhance clinicians’ understanding of this rare disease.Patient concerns:We screened and identified 25 cases of IVL at our hospital from October 2013 to January 2020. Five patients had tumors.Diagnoses:The diagnosis in each case was pathologically confirmed after surgical treatment.Interventions:All patients were managed surgically. Although the surgical procedures were different, the surgical approach was geared towards achieving complete excision. Three patients received hormonal therapy with gonadotropinreleasing hormone agonists after surgery.Outcomes:We retrospectively reviewed all medical records and analyzed the clinicopathologic features and clinical outcomes of this disease as well as the correlations between the clinical features and risk of recurrence. Neither the symptoms nor the preoperative imaging results were suggestive of IVL in any of the cases. Except for two patients who were lost to follow-up, twenty-three patients who were followed up are still alive. Three patients experienced a recurrence.Lessons:The clinical manifestations and ultrasound images of IVL in the early stages are not typical; thus, IVL is easily misdiagnosed as uterine leiomyoma. Radiologists, pathologists, and surgeons should have a thorough understanding of IVL and a high index of vigilance for IVL in clinical practice. Surgery should always be aimed at achieving complete tumor excision. Patients with large lesions (≥7 cm) and lesions extending to the broad ligament may have an increased risk of recurrence. Early detection, diagnosis, and treatment are very important; once the diagnosis is confirmed, regular follow-ups are crucial.  相似文献   
135.
Hormetic response is an adaptive mechanism for a cell or organism surviving in an unfavorable environment. It has been an intriguing subject of researches covering a broad range of biological and medical disciplines, in which the underlying significance and molecular mechanisms are under intensive investigation. In the present study, we demonstrated that topoisomerase I inhibitor camptothecin (CPT), a potent anticancer agent, induced an obvious hormetic response in rat pheochromocytoma PC12 cells. Camptothecin inhibited PC12 cell growth at relative high doses as generally acknowledged while stimulated the cell growth by as much as 39% at low doses. Moreover, low doses of CPT protected the cells from hydrogen peroxide (H2O2)-induced cell death. Phosphoinositide 3-kinase (PI3K)/Akt and nuclear factor-E2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathways were reported playing pivotal roles in protecting cells from oxidative stress. We observed that these 2 pathways were upregulated by low doses of CPT, as evidenced by increased levels of phosphorylated PI3K, phosphorylated Akt, phosphorylated mammalian target of rapamycin, Nrf2, and HO-1; and abolishment of the growth-promoting and neuroprotective effects of CPT by LY294002, a PI3K inhibitor. These results suggest that the hormetic and neuroprotective effects of CPT at low doses on PC12 cells were attributable, at least partially, to upregulated PI3K/Akt and Nrf2/HO-1 pathways.  相似文献   
136.
This study explored the effects of humic acid (HA) on the toxicity of ZnO nanoparticles (nano‐ZnO) and Zn2+ to Anabaena sp. Typical chlorophyll fluorescence parameters, including effective quantum yield, photosynthetic efficiency and maximal electron transport rate, were measured by a pulse‐amplitude modulated fluorometer. Results showed that nano‐ZnO and Zn2+ could inhibit Anabaena sp. growth with the EC50 (concentration for 50% of maximal effect) of 0.74 ± 0.01 and 0.3 ± 0.01 mg/L, respectively. In the presence of 3.0 mg/L of HA, EC50 of nano‐ZnO increased to 1.15 ± 0.04 mg/L and EC50 of Zn2+ was still 0.3 ± 0.01 mg/L. Scanning electron microscopy observation revealed that HA prevented the adhesion of nano‐ZnO on the algae cells due to the increased electrostatic repulsion. The generation of intracellular reactive oxygen species and cellular lipid peroxidation were significantly limited by HA. Nano‐ZnO had more damage to the cell membrane than Zn2+ did, which could be proven by the malondialdehyde content in Anabaena sp. cells. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 895–903, 2015.  相似文献   
137.
138.
Although unstable angina can be initially controlled with medical therapy in most patients, there is a high incidence of subsequent death, myocardial infarction, or need for coronary bypass surgery to control symptoms. Identification at the time of presentation of the patient likely to do poorly on continued medical therapy would be useful in advising consideration of surgical therapy. Since coronary arterial spasm may have a significant role in the pathophysiology of unstable angina in some patients, the recently developed calcium channel antagonists may therefore be of particular benefit in the medical therapy of unstable angina. One hundred thirty-eight patients were entered into a randomized double-blind study of the efficacy of adding nifedipine to conventional treatment of unstable angina (nitrates and beta-blockers) and were followed for 18 months. Of these patients, 104 underwent coronary arteriography. A multivariate Cox's hazard function analysis was applied to variables selected from the history, electrocardiographic (ECG) changes during chest pain, and from scintigraphic and coronary arteriographic data to determine those variables most predictive of response to medical therapy. The percentage of the left ventricular myocardium supplied by vessels with 70% or greater luminal stenosis was the most significant variable in influencing failure of medical therapy defined as sudden death, myocardial infarction, or need for bypass surgery. Whether or not the patient received nifedipine was the second most powerful variable, with the use of nifedipine reducing by half the relative risk of failing medical therapy. These were followed by cigarette smoking and presence of global ST segment changes during ischemia. After 18 months the nifedipine group had fewer patients failing medical therapy (p = .02), with fewer patients undergoing coronary bypass surgery (p less than .01). However, nifedipine did not appear to have a preventive effect against myocardial infarction or death. Kaplan-Meier actuarial curves confirmed that medical therapy was significantly less successful in the presence of increasing numbers of significantly stenotic vessels (p = .03). However, nifedipine provided a significant beneficial effect in patients with two or more stenotic vessels (p less than .01) and in whom 50% or more of the myocardium was supplied by vessels with 70% or greater stenosis (p = .01). Thus, although patients with advanced obstructive coronary disease have the greatest likelihood of unfavorable outcomes, the addition of nifedipine is of significant benefit.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
139.
140.
目的 探讨玻璃化冷冻胚胎移植(FET)和新鲜胚胎移植(NET)的临床结局。方法回顾性分析2013年1月至2014年3月在中山大学孙逸仙纪念医院行体外受精-新鲜胚胎移植(IVF-NET)577个周期及单精子卵细胞浆内显微注射-新鲜胚胎移植(ICSI-NET)118个周期、FET 175个周期共870个周期的临床资料,比较NET组和FET组(曾经NET未成功妊娠,后行FET者)的临床特征和助孕结局,再将FET组分为妊娠亚组和未妊娠亚组进一步分析比较。采用二分类logistic回归分析影响妊娠结局的因素。结果 FET组的种植率(26.27% vs. 31.98%,P=0.01)、临床妊娠率(47.43% vs. 65.18%,P<0.001)均明显低于NET组,差异均有统计学意义;FET组的流产率(P=0.63)、生化妊娠率(P=0.17)和胎儿出生体重(P=0.33)与NET组相比差异均无统计学意义。FET组中妊娠亚组与未妊娠亚组女方年龄(30.69岁±3.37岁 vs. 32.00岁±5.09岁,P=0.03)的差异有统计学意义;BMI、不孕年限、基础内分泌等指标的差异均无统计学意义。二分类logistic回归分析显示是否行FET(P<0.001)、女方年龄(P<0.001)、BMI(P=0.011)和优质胚胎数(P<0.001)为影响妊娠结局的因素。结论 曾经行NET未成功的妊娠者,随后使用FET者其种植率和妊娠率均较低,但不增加流产率,未影响胎儿出生体重,未发现FET对妊娠结局有不良影响。  相似文献   
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