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101.
IL-5, IL-10 and lipopolysaccharide (LPS) are known to activateB-1 cells in vivo in normal mice and anti-red blood cell autoantibodytransgenic mice (HL mice). To assess the exact role of IL-5in proliferation and activation of peritoneal B-1 cells, weanalyzed IL-5 receptor chain-deficient HL (IL-5R–/–x HL) mice generated by the cross between IL-5R–/–and HL mice. In IL-5R–/– x HL mice, Ig-producingB-1 cells in the peritoneal cavity were negligible, althoughthe total number of B-1 cells in the peritoneal cavity wereas many as 30% of that in HL mice. Moreover, LPS- or IL-10-induceddifferentiation of B-1 cells into antibody-producing cells wasseverely impaired in IL-5R–/– x HL mice. We alsoused in vivo 5-bromo-2'-deoxyuridine labeling to estimate theproliferation of B-1 cells in IL-5R–/– mice. Theabsence of IL-5R did not affect spontaneous proliferation ofperitoneal B-1 cells. However, induced proliferation of peritorealB-1 cells by oral administration of LPS was markedly impairedin IL-5R–/– mice. These results suggest that IL-5is required for activation-associated proliferation of B-1 cellsbut not for their spontaneous proliferation and support theidea that IL-5 plays an important role on the induction of autoantibodyproduction from B-1 cells.  相似文献   
102.
Single doses of procarbazine (MIH) were injected IP at 0, 50, 100, 200, and 400 mg/kg body weight to CD-1 male mice. Activities of hyaluronidase, lactate dehydrogenase isoenzyme-X, and the dehydrogenases of sorbitol, -glycerophosphate, glucose-6-phosphate, malate, isocitrate, and glyceraldehyde-3-phosphate in the testes of the mice were determined and correlated with changes in spermatogenic cell types in seminiferous tubules. All enzyme activities were higher than controls or remained unchanged on days 10–20 after drug treatment. Activities of hyaluronidase, sorbitol dehydrogenase, and lactate dehydrogenase isoenzyme-X decreased significantly to below normal levels on day 30 after drug treatment for all doses, whereas those of the other five dehydrogenases remained significantly higher than controls. All enzyme activities approached control levels with the concomitant recovery of spermatogenesis by day 60 after drug treatment. Histological examination of seminiferous tubules revealed that premeiotic spermatocytes were significantly reduced on days 10–20 but reappeared on day 30 after MIH treatment (400 mg/kg). The postmeiotic spermatogenic cells were unaffected at the time of MIH treatment, but had disappeared completely on day 30 after drug treatment. MIH, at the highest dosage, selectively destroyed spermatogonia and premeiotic spermatocytes; however spermatozoa and elongated spermatides were unaffected. This study demonstrated that the cytotoxic effect of MIH on spermatogenesis could be evaluated via changes in testicular enzyme activities. The present studies demonstrated that hyaluronidase, sorbitol dehydrogenase, and lactate dehydrogenase isoenzyme-X could serve as useful biochemical markers for assessing testicular toxicity induced by drugs and chemicals.  相似文献   
103.
中药在疾病预防和治疗的过程中发挥重大作用,但部分中药在临床的长期应用过程中,给人体带来的不良反应也逐渐显现出来,肝损伤属于其中之一。肝损伤也是中药新药研发过程中作为临床安全用药的重要检查项目,已成为众多上市药物退出市场的重要原因。随着对中药临床用药安全性的关注增加,关于中药肝损伤研究日益增多,大多数研究集中于中药或者中药成分的肝脏损伤研究。为了提高中药的安全性,该文总结了部分致肝损伤中药的物质基础和机制及降低中药肝损伤的措施,包括减少给药剂量和疗程,改变给药途径,改变药物剂型,药物配伍和炮制等方法;此外该文还总结了防治各种诱导物诱发肝损伤的单体中药、中药复方和中药成分及防治肝损伤的生物效应和作用机制。结合现代致肝损伤中药的减毒研究,提出明确致肝损伤中药的安全剂量和“毒-效”界限,明确减毒措施的减毒机制及确定致肝损伤中药的毒性物质基础,为致肝损伤中药的临床应用提供安全性保障;结合中药防治肝损伤的研究,提出加强中药防治肝损伤的临床研究的同时,利用现代科学技术“从局部到整体”来阐释中药复方防治肝损伤的科学内涵,进而为临床防治肝损伤提供科学依据。  相似文献   
104.
Nowadays, obesity is one of the great nutritional problems facing public health. The prevalence of this pathology has increased in a worrying way over recent years, currently reaching epidemic proportions. In this context, nutritional supplements are presented as a therapeutic alternative to which more and more people are turning to. Nutritional supplements to lose weight based on the Garcinia plant, specifically on Garcinia cambogia, are commonly used. The active principle of this plant to which these properties have been attributed, is hydroxycitric acid (HCA). The aim of the present review is to gather reported data concerning the effectiveness of nutritional supplements based on Garcinia extracts on weight loss and their possible negative effects. Contradictory results have been observed regarding the effectiveness of the supplements. While statistically significant weight loss was observed in some studies, no changes were found in others. Regarding safety, although Garcinia supplements have been revealed as safe in the vast majority of the studies carried out in animal models and humans, some cases of hepatotoxicity, serotonin toxicity and mania have been reported. In conclusion, the results suggest that Garcinia-based supplements could be effective in short-term weight loss, although the data are not conclusive. In addition, the safety of the complement should be further studied.  相似文献   
105.
Lately, matcha green tea has gained popularity as a beverage and food additive. It has proved to be effective in preventing obesity and related metabolic syndromes. However, the underlying mechanisms of its control effects against non-alcoholic fatty liver disease (NAFLD) are complicated and remain elusive. In the present study, we performed an in vivo experiment using male C57BL/6 mice fed with a high-fat diet and simultaneously treated with matcha for six weeks. Serum biochemical parameters, histological changes, lipid accumulation, inflammatory cytokines, and relevant indicators were examined. Dietary supplementation of matcha effectively prevented excessive accumulation of visceral and hepatic lipid, elevated blood glucose, dyslipidemia, abnormal liver function, and steatosis hepatitis. RNA sequencing analyses of differentially expressed genes in liver samples indicated that matcha treatment decreased the activity of lipid droplet-associated proteins and increased the activity of cytochrome P450 enzymes, suggesting improved metabolic capacity and liver function. The current study provided evidence for new dietary strategies based on matcha supplementation to ameliorate lipotoxicity-induced obesity and NALFD.  相似文献   
106.
Shiga toxin–producing Escherichia coli (STEC) O80:H2 has emerged in Europe as a cause of hemolytic uremic syndrome associated with bacteremia. STEC O80:H2 harbors the mosaic plasmid pR444_A, which combines several virulence genes, including hlyF and antimicrobial resistance genes. pR444_A is found in some extraintestinal pathogenic E. coli (ExPEC) strains. We identified and characterized 53 STEC strains with ExPEC-associated virulence genes isolated in Italy and the Netherlands during 2000–2019. The isolates belong to 2 major populations: 1 belongs to sequence type 301 and harbors diverse stx2 subtypes, the intimin variant eae-ξ, and pO157-like and pR444_A plasmids; 1 consists of strains belonging to various sequence types, some of which lack the pO157 plasmid, the locus of enterocyte effacement, and the antimicrobial resistance–encoding region. Our results showed that STEC strains harboring ExPEC-associated virulence genes can include multiple serotypes and that the pR444_A plasmid can be acquired and mobilized by STEC strains.  相似文献   
107.
嘎木朱尔涂膜剂的毒性试验研究   总被引:4,自引:0,他引:4  
目的:为使嘎木朱尔涂膜剂的临床用药安全、合理,而对其毒性作用进行了考察。方法:将嘎木朱尔涂膜剂分为高、中、低三个剂量组(按其浓度为0.172g/ml,0.086g/ml,0.043g/ml)给药,用于家兔皮肤,同时做空白基质对照,测定其涂膜剂对家兔皮肤的急性毒性、长期毒性试验。结果:各给药剂量组和空白基质对照组对家兔的体重增长,脏器系数(g/ml)、血液常规,生物化学等项指标的测定均无显著性差异(P<0.05)。结论:嘎木朱尔涂膜剂用于家兔皮肤无毒并能加快受损皮肤的愈合。  相似文献   
108.
新生儿溶血与HPVB_(19)感染的关系探讨   总被引:1,自引:0,他引:1  
目的:用红细胞破坏增多和红细胞生成增多的实验检查证实HPVB19 感染引起新生儿溶血。方法 :对45例用PCR方法确诊为HPVB19 感染 (已除外ABO血型不合、Rh阳性、G -6PD酶缺陷症、地中海贫血、败血症、弓形虫、单纯疱疹病毒、风疹病毒、CMV及乙肝病毒等感染 )的新生儿病理性黄疸患儿进行结合珠蛋白 (Hp-Hb)、游离血红蛋白、间接胆红素、直接胆红素、在不同程度上血红蛋白 (Hb)、尿胆元及网织红细胞检查。结果 :45例HPVB19 感染患儿均存在红细胞破坏增多和红细胞生成增多的证据。结论 :在新生儿溶血性黄疸患儿中存在HPVB19 感染  相似文献   
109.
改良Coombs试验对诊断自身免疫性溶血性贫血的价值   总被引:5,自引:0,他引:5  
目的:比较经典Coombs试验、改良Coombs试验、单抗Coombs分型试验,寻找更灵敏的方法诊断自身免疫性溶血性贫血(AIHA)。方法:对45例临床怀疑为AIHA病人依次进行经典Coombs试验、改良Coombs试验、单抗Coombs分型试验。结果:5例经过临床观察及相关检查发现为其它疾病;30例经典Coomb试验( );36例改良Coombs试验IgG( );40例单抗Coombs分型试验( );IgG1( )患最多(27例,为总数,下同),IgG3( )其次(20例),IgG2( )较少(14例),IgG4( )最少(9例),1例未检出任何亚型。还发现经典Coombs试验灵,敏度为75.5%,改良Coombs试验灵敏度为90.0%,单抗Coombs分型试验灵敏2度为97.5%。结论:温抗体IgG4种亚型主要为IgG1,某些病例可见IgG3,IgG2少见,IgG4罕见;单抗Coombs分型试验比经典Coombs试验及改良Coombs试验敏感。  相似文献   
110.
强氧酸性离子水毒性试验研究   总被引:4,自引:0,他引:4  
目的 了解新型消毒剂强氧酸性离子水的毒性。方法 采用一次性限量灌胃法测定急性经口LD50;采用剂量递增蓄积系数法测定蓄积毒性;采用取样前30小时、6小时两次给予受试物法测定其对小鼠骨髓嗜多染红细胞微核形成的影响;用斑贴法测定其对动物的皮肤刺激强度;用棉条浸入法测定其对大鼠阴道粘膜的刺激强度。结果急性经口LD50大于21500mg/kg·bw,属实际无毒物,蓄积试验属弱蓄积性,对小鼠骨髓微核细胞未见损伤作用,对家兔皮肤和大鼠阴道粘膜无刺激。结论 强氧酸性离子水是一种安全的消毒剂。  相似文献   
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