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41.
Zhang  Jing  Zhang  Yunqing  Qin  Jinglin  Lu  Sha  Cai  Wenying  Li  Jiahao  Huang  Huaiqiu  Yang  Sulian  Xi  Liyan 《Lasers in medical science》2021,36(1):147-152
Lasers in Medical Science - Onychomycosis is a fungal infection of the nail. The aim of this randomized controlled clinical trial was to compare the efficacy of 2940-nm Er:YAG laser treatment...  相似文献   
42.
Hepatic ischemia–reperfusion injury (HIRI) is of common occurrence during liver surgery and transplantation. Pinocembrin (PIN) is a kind of flavonoid monomer extracted from the local traditional Chinese medicine Penthorum chinense Pursh (P. chinense). However, the effect of PIN on HIRI has not determined. We investigated the protective effect and potential mechanism of PIN against HIRI. Model mice were subjected to partial liver ischemia for 60 min, experimental mice were pretreated with PIN orally for 7 days, and H2O2-induced oxidative damage model in AML12 hepatic cells was established in vitro. Histopathologic analysis and serum biochemical levels revealed that PIN had hepatoprotective activities against HIRI. The variation of GSH, SOD, MDA, and ROS levels indicated that PIN treatments attenuated oxidative stress in tissue. PIN pretreatment obviously ameliorated apoptosis, and restrained the expression of HMGB1 and TLR4 in vivo. In vitro, compared with H2O2 group, the contents of ROS, mitochondrial membrane potential, apoptotic cells, and Bcl-2 protein were decreased, while the Bax protein expression was increased. Moreover, HMGB-1 small interfering RNA test and western blotting showed that PIN pretreatment reduced HMGB1 and TLR4 protein levels. In conclusion, PIN pretreatment effectively protected hepatocytes from HIRI and inhibited the HMGB1/TLR4 signaling pathway.  相似文献   
43.
44.
用地高辛标记反意前阿黑皮素(pro-opiomelanocortin,POMC)cRNA探针原位杂交组化在光镜和电镜水平观察了POMC mRNA在大鼠垂体的分布,并比较了碱性磷酸酶(AKP)显色系统和辣根过氧化酶(HRP)显色系统在光镜水平上的敏感性.结果:POMC mRNA广泛地分布于垂体的中间叶和前叶.中间叶全部细胞均为POMC mRNA阳性.前叶中除前叶的腹侧缘和前叶与中间叶交界处阳性细胞较少外,都有较多的POMC mRNA阳性细胞分布.AKP显色系统比HRP显色系统敏感.在电镜水平,POMC mRNA主要分布于粗面内质网,少数分泌颗粒可能呈阳性反应,胞核未见阳性反应沉淀.文内还就阳性分泌颗粒在调节细胞合成功能方面可能起的作用进行了讨论.  相似文献   
45.
We report the prevalence rates for dementia and Alzheimer's disease (AD) obtained from a probability sample survey of 5,055 noninstitutionalized older persons in Shanghai, China. A two-stage procedure was used for case finding and case identification. A Chinese version of the Mini-Mental State Examination was used to determine cases of possible dementia. Three different cutoff points on this mental status test were used depending on the respondent's level of education. Clinical evaluations, based on functional assessments and psychiatric interview, medical and neurological examinations, three standardized mental status tests, and a selected group of psychometric tests, were made in the second stage of the study to ascertain the clinical diagnosis of dementia and AD utilizing the Diagnostic and Statistical Manual for Mental Disorders, edition 3 and National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association criteria, respectively. The prevalence rate of dementia in persons 65 years and older was 4.6%. Clinically diagnosed AD accounted for 65% of the subjects with dementia. These findings indicate that the prevalence of dementia in Shanghai is very much higher than figures published earlier for China and Japan, and at the lower part of the range of values reported for community residents in the United States and other Western countries, but less than half of that reported in the recently published survey of the elderly in East Boston. Increasing age, gender (female), and low education are each highly significant and independent risk factors for dementia. One hypothesis to explain the increased prevalence in elderly women who had received no formal education invokes the possibility of an effect of early deprivation, perhaps lowering brain "reserve," allowing the symptoms of dementia to appear at an earlier date during disease progression.  相似文献   
46.
棉酚衍生物和类似物的抗生育作用   总被引:4,自引:0,他引:4  
  相似文献   
47.
冠状动脉粥样硬化性心脏病的当代治疗   总被引:4,自引:4,他引:0  
蔡振杰 《医学争鸣》2000,21(5):521-523
0 引言冠状动脉粥样硬化性心脏病(简称冠心病)治疗在20世纪60年代以前是药物治疗为主,到了20世纪70年代,外科采用冠状动脉旁路术开辟了冠心病治疗的新途径.进入20世纪80年代,冠状动脉旁路术在西方发达国家已经非常成熟,非常普遍.同时期,内科介入治疗也迅速发展起来,下面就各种治疗方法的进展分别进行讨论.1 内科治疗1.1 药物治疗 冠心病的药物治疗随着患者病情不同而不同.对一般常有心绞痛发作的患者常用药物主要有两类,一类是扩张冠状动脉血管,减轻心脏缺血,缓解或预防心绞痛.这类药物主要有硝酸盐制剂,如硝酸甘油、亚硝酸异戊酯、四硝…  相似文献   
48.
大肠癌新相关基因HSU17714的染色体定位研究   总被引:6,自引:0,他引:6  
Cai X  Zhang Y  Geng L 《中华肿瘤杂志》1997,19(3):177-179
目的确定大肠癌新相关基因HSU17714的染色体定位。方法采用强化荧光原位杂交技术(FISH),以生物素化酪胺强化荧光原位杂交信号。结果80.0%(128/160)的间期细胞和59.8%(104/174)的中期分裂相可见到明显集中的HSU17714基因的杂交信号,相应荧光R带分析中,85.1%(40/47)在22号染色体上1区3带处有杂交信号。结论HSU17714基因定位于22q13。  相似文献   
49.
Cai Q  Rahn RO  Zhang R 《Cancer letters》1997,119(1):99-107
Several dietary flavonoids such as quercetin, luteolin and genistein have been suggested to have cancer chemopreventive effects, although the mechanisms are not fully understood. In the present study, the effects of these flavonoids as antioxidants were investigated in the following systems: (1) production of hydrogen peroxide (H2O2) and superoxide anion (O2*-), (2) lipid peroxidation induced by FeCl2 in rat liver, and (3) formation of 8-hydroxy-2'-deoxyguanosine (8-OHdG) induced by either UV or Fenton reaction in calf thymus DNA. The results showed that quercetin and luteolin were equally potent in scavenging H2O2, with genistein having a moderate effect. Quercetin and luteolin had a potent inhibitory effect on O2*- generation by xanthine/xanthine oxidase while genistein had a moderate effect. Quercetin and luteolin were potent in inhibiting lipid peroxidation induced by FeCl2 in rat liver while genistein had a very weak inhibitory effect. All the test compounds had a potent quenching effect on 8-OHdG formation induced by UV light irradiation, with the order of effects being genistein > luteolin > quercetin. Of the test compounds, luteolin exhibited the most potent quenching effect on Fenton-induced 8-OHdG formation. The scavenging of oxygen free radicals, the inhibitory effect on lipid peroxidation and the quenching effect on 8-OHdG formation by quercetin, luteolin and genistein may, at least in part, be responsible for their anticarcinogenic effects.  相似文献   
50.
The DNA topoisomerase I inhibitors, 10-hydroxycamptothecin (HCPT) and camptothecin (CPT), are indole alkaloids isolated from the Chinese tree, Camptotheca acuminata. They have been shown to have a wide spectrum of anticancer activity both in vitro and in vivo. However, their use has been limited due to their water-insolubility. The purpose of the present study was 2-fold, to determine the in vitro and in vivo activity of HCPT and CPT against human breast cancer and to determine the pharmacokinetics of the two drugs to better understand how they can best be used therapeutically. The bl vitro inhibitory effect on tumor growth was observed with breast cancer cell line MDA-MB-468. The in vivo antitumor effects were then determined using severe combined immunodeficient (SCID) mice bearing MDA-MB-468 xenografts. The tumor-bearing mice were orally administered HCPT (1, 3, 6, 9 mg/kg/day, 5 days per week) or CPT (1, 3, 6 mg/kg/day, 5 days per week) for 3 weeks. Growth of the MDA-MB-468 cells was inhibited by HCPT and CPT in vitro and in vivo in a dose-dependent manner. Complete regression of the tumor xenografts, determined by tumor measurement and microscopic examination, occurred in the groups of animals treated with doses of HCPT or CPT of 3 mg/kg/day or more. In general, HCPT was more effective and less toxic than CPT. To determine the potential mechanisms for the pharmacologic differences, the comparative pharmacokinetics of HCPT and CPT were determined in tumor-bearing SCID mice following i.v. or oral administration of H-3-HCPT or H-3-CPT. Parent drugs and their metabolites in plasma, urine, feces, and various tissues were quantified by a recently developed reversed-phase HPLC method. Significant absorption of both HCPT and CPT was observed after oral administration, with CPT having a higher bioavailability. HCPT and CPT were distributed widely into various tissues including the tumor, enterohepatic system, kidneys, and bone marrow. These studies indicate that HCPT and CPT are of potential use in treatment of breast cancer, providing the basis for the design of future human trials with these anticancer drugs.  相似文献   
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