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61.
To determine structural features necessary for the production of direct mutagenic activity from oligoamine-nitrate reaction mixtures, we systematically tested a group of aliphatic amine substrates for comutagenic action with nitrite. The ability to react with nitrite and form direct-acting mutagenic derivatives was common to a reasonably well defined class of aliphatic polyamines. In general, primary-secondary diamino compounds were mutagenic in the Ames Salmonella tester system when reacted with nitrite, whereas primary and secondary amines produced no direct mutagenic activity when tested separately. In combination with teritary amino groups, primary amines were inactive; one secondary-tertiary amine was tested, and this substrate produced mutagenic activity.  相似文献   
62.
Metabolic syndrome is a worldwide health problem, and obesity is closely related to type 2 diabetes, cardiovascular disease, hypertension, and cancer. According to WHO in 2018, the prevalence of obesity in 2016 tripled compared to 1975. D. morbifera reduces bad cholesterol and triglycerides levels in the blood and provides various antioxidant nutrients and germicidal sub-stances, as well as selenium, which helps to remove active oxygen. Moreover, D. morbifera is useful for treating cardiovascular diseases, hypertension, hyperlipidemia, and diabetes. Therefore, we study in vivo efficacy of D. morbifera to investigate the prevention effect of obesity and cholesterol. The weight and body fat were effectively reduced by D. morbifera water (DLW) extract administration to high-fat diet-fed C57BL/6 mice compared to those of control mice. The group treated with DLW 500 mg∙kg−1∙d−1 had significantly lower body weights compared to the control group. In addition, High-density lipoprotein (HDL) cholesterol increased in the group treated with DLW 500 mg∙kg−1∙d−1. The effect of DLW on the serum lipid profile could be helpful to prevent obesity. DLW suppresses lipid formation in adipocytes and decreases body fat. In conclusion, DLW can be applied to develop anti-obesity functional foods and other products to reduce body fat.  相似文献   
63.
分别采用化学、声化学及光辐射等方法合成了1-丙二烯基-2,3,4,6四-氧-乙酰基-β-D-吡喃糖苷,结果表明声化学方法最有效、快速;借助电子自旋共振(ESR)技术及相关实验,证实此类糖苷的生成为一离子消除反应,所合成的糖苷化合物脱去乙酰基后对T、B淋巴细胞具有体外免疫调节作用。  相似文献   
64.
采用外耳道及鼓室再造术治疗先天性外耳道完全闭锁29例。统计各种外、中耳畸形情况,比较耳廓发育程度、颞骨相当于外耳道口处有无骨性小凹、术前听力损失程度与中耳畸形的关系,将术前的常规横断位CT检查结果与术中所见进行对照。结果显示,术前可通过耳廓发育程度、相当于外耳道口处有无骨性小凹、听力损失程度和颞骨CT扫描来综合估计中耳畸形情况,为术前了解手术难度和确定手术进路及方式提供一定的参考依据。  相似文献   
65.
66.
Annals of Surgical Oncology - Management of axillary lymph nodes in breast cancer has undergone significant change over the past decade through landmark clinical trials. This study aimed to assess...  相似文献   
67.
PurposeTo investigate the clinical characteristics, chemosensitivity, and outcome of metastatic upper tract urothelial carcinoma (UTUC).Patients and MethodsRecords of patients with metastatic UTUC since January 2005 were retrieved from a database that included clinical and survival data. Statistical analyses including survival and multivariate analyses of factors were respectively performed by the Kaplan-Meier method and Cox proportional hazard model.ResultsA total of 250 consecutive UTUC cases were evaluated. There were 56 patients (22.4%) with initially diagnosed stage IV disease. The most common metastatic sites were lung (39.6%), distant lymph nodes (39.2%), bone (19.6%), liver (18.0%), and adrenal gland (7.2%), respectively, and the local recurrence rate was 10.4%. Two hundred thirteen patients received first-line chemotherapy. The overall response rate was only 28.7% and the median progression-free survival time was only 5.0 months. The overall survival time of the cohort was 18.0 months. Multivariate analyses showed that initially diagnosed stage IV disease, number of metastatic organs ≥3, no response to chemotherapy and cycles of chemotherapy ≤2 were adverse prognosticators for overall survival.ConclusionUTUC presented to be more prone to metastasize than locally recur and thought to have low chemosensitivity. Stage IV disease at initial diagnosis, number of metastatic organs, response and cycles of chemotherapy were independent prognosticators for metastatic UTUC.  相似文献   
68.
目的探讨如何利用CT表现对肾上腺隐匿型嗜铬细胞瘤和肾上腺皮质腺瘤进行鉴别诊断。方法收集2010年1月至2020年1月期间中国医科大学附属第一医院收治的177例肾上腺肿瘤患者进行回顾性分析,对比各组患者之间的一般临床资料和CT表现。结果隐匿型嗜铬细胞瘤56例、皮质醇腺瘤32例、醛固酮腺瘤44例、无功能腺瘤45例,隐匿型嗜铬细胞瘤组在肿瘤侧别上与无功能腺瘤组差异有统计学意义,在肿瘤最大直径、平扫CT值、动脉期和延迟期增强CT值上均显著大于三组肾上腺腺瘤组。以肿瘤直径≥2.95 cm诊断隐匿型嗜铬细胞瘤,曲线下面积(AUC)为0.872,敏感度为87.5%,特异性为76.0%;当平扫CT值≥24.5 Hu时,AUC为0.929,敏感度为94.0%,特异性为82.5%;当动脉期增强CT值≥89.5 Hu时,AUC为0.886,敏感度为72.7%,特异性为90.6%;当延迟期增强CT值≥82.5 Hu时,AUC为0.937,敏感度为84.6%,特异性为95.3%;联合以上四个指标时,AUC为0.981,阈值为≥0.118,敏感度为100%,特异性为90.6%。结论以肿瘤直径2.95 cm、平扫CT值24.5 Hu、动脉期增强CT值89.5 Hu和延迟期增强CT值82.5 Hu为阈值对肾上腺隐匿型嗜铬细胞瘤有较好的鉴别诊断价值。  相似文献   
69.
A pseudotumor appearance of the liver has not been previously described in chronic hepatitis. We reviewed 81 charts with a biopsy diagnosis of "chronic hepatitis" and at least one radiologic liver scan, and found four cases with a pseudotumor appearance. They all had features on radiologic scans suggestive of space-occupying lesions. Histology showed chronic hepatitis in all four. Two were cirrhotic, one due to alcohol and the other due to hepatitis B. The other two patients had chronic active hepatitis with regenerative nodules but only limited fibrosis, one due to hepatitis B, the other probable non-A, non-B. None had any evidence of hepatic malignancy. We conclude that some patients with chronic hepatitis may present with a pseudotumor appearance on radiological scans, due to the presence of regenerative nodules. Space-occupying lesions on liver scans in chronic hepatitis may represent non-neoplastic liver disease.  相似文献   
70.
OBJECTIVE: To establish an animal model of mitochondrial DNA (mtDNA) deletion and investigate the possible role of mtDNA deletion in aminoglycoside antibiotic induced deafness. METHODS: Thirty wistar rats (4 months) were randomly divided into group A and B. Doxorubicin (DOX) was subcutaneously injected at doses of 2 mg/kg twice per week for 3 months in group A and then kanamycin (KM) was intraperitoneally injected 500 mg/kg per day for 10 consecutive days. The treatments of group B were identical to group A, except normal saline was substituted for DOX. The thresholds of auditory brainstem response (ABR) were measured before and after the drug administrations. The inner ear membranous labyrinthine tissue was harvested and mtDNA was amplified to identify 4,834 bp deletion by PCR technique. RESULTS: The elevation of the mean ABR thresholds in group A(67.08 +/- 8.59) dB peSPL was significantly higher than that in group B (12.71 +/- 4.42) dB peSPL after KM administration (P < 0.001). In group A, 9 of the 15 rats demonstrated 4,834 bp mtDNA deletion. However, mtDNA 4,834 bp deletion was negative in group B animals. CONCLUSION: DOX can induce mtDNA deletion in the inner ear tissue of the rat. mtDNA deletion in the inner ear may play an important role in the hypersensitivity to aminoglycoside antibiotic ototoxicity.  相似文献   
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