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11.
本文以兔呼吸频率、通气量和血气作为指标,观察到iv吗啡0.5~4.0mg/kg产生剂量依赖性呼吸抑制。icv匹鲁卡品2.5mg/kg能完全逆转这一抑制效应。icv 4—氨基吡啶(4—AP),1.5μg/kg兴奋呼吸,并使吗啡量效曲线右移。用利血平耗竭儿茶酚胺后,吗啡仍能抑制呼吸,4—AP可消除之。表明吗啡抑制呼吸与中枢胆碱能系统有关,且可能系它抑制Ach释放所致。  相似文献   
12.
OBJECTIVE: To study the effect of eucalyptus globulus oil on the activity of nuclear factor-kappaB(NF-kappaB) in THP-1 cell line. METHODS: THP-1 cells were cultured with or without eucalyptus globulus oil at different concentrations (1, 10, 100 mg x L(-1), 30 min) before being stimulated with lipopolysaccharide (LPS, 1 mg x L(-1), 30 min). The location of NF-kappaB p65 subunit (NF-kappaB/p65) in THP-1 cells was detected by indirect immunofluorescence and laser scanning confocal microscope. The expression of NF-kappaB/p65 in nuclei was measured by Western-blot analysis. RESULT: The FITC-label NF-kappaB/p65 was mainly located in the nuclei after THP-1 cells were stimulated with LPS. Whereas, no fluorescence were seen in the nuclei of cells pretreated with eucalyptus globulus oil. This effect on NF-kappaB/p65 nuclear translocation was in a concentration dependent manner. CONCLUSION: Eucalyptus globulus oil inhibits the nuclear translocation of NF-kappaB induced by LPS in THP-1 cells.  相似文献   
13.
(1)目的 总结探讨11例非体外循环冠状动脉搭桥术(OPCAB)的经验。(2)方法 2001年6-12月对11例冠心患采用非体外循环心脏不停跳方法完成冠状动脉搭桥术。(3)结果 共搭桥35支,平均3.17支/例,其中左乳内动脉桥8支,大隐静脉桥27支。6例患(54.5%)未血,无手术死亡及并发症。(4)结论 非体外循环搭桥术克服了体外循环搭桥术(CABG)的诸多缺点和弊端,手术简化,时间缩短,适应证扩大,并发症明显减少,效果满意。  相似文献   
14.
通过实验室和口腔科临床观察表明:TD清洗消毒剂(氯化磷酸三钠)对金黄色葡萄球菌、绿脓杆菌和枯草杆菌黑色变种的平均杀菌率为100.0%,对口腔科器械消毒无菌率为100%,对被HBsAg阳性血清污染的器械浸泡30分钟转阴率为98.1%。其消毒效果优于新洁尔灭,与戊二醛相同。在口腔科使用两年,未见金属器械有锈斑生成。  相似文献   
15.
Patients with Crohn's disease have an increased risk of developing intestinal tumours. However, the carcinogenic mechanisms remain poorly understood. To address this question, this report describes an unusual case of Crohn's disease complicated by synchronous small intestinal and colonic adenocarcinomas. Genetic events in both the tumours and their adjacent mucosae were evaluated and the tumorigenesis of these cancers is discussed.  相似文献   
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17.
Wang  Yu  Lin  Zhijian  Zhang  Bing  Nie  Anzheng  Bian  Meng 《Nutrition & metabolism》2021,18(1):1-11
The study of sex differences in hyperuricemia can provide not only a theoretical basis for this clinical phenomenon but also new therapeutic targets for urate-lowering therapy. In the current study, we aimed to confirm that estradiol can promote intestinal ATP binding cassette subfamily G member 2 (ABCG2) expression to increase urate excretion through the PI3K/Akt pathway. The estradiol levels of hyperuricemia/gout patients and healthy controls were compared, and a hyperuricemia mouse model was used to observe the urate-lowering effect of estradiol and the changes in ABCG2 expression in the kidney and intestine. In vivo and in vitro intestinal urate transport models were established to verify the urate transport function regulated by estradiol. The molecular pathway by which estradiol regulates ABCG2 expression in intestinal cells was explored. The estradiol level of hyperuricemia/gout patients was significantly lower than that of healthy controls. Administering estradiol benzoate (EB) to both male hyperuricemic mice and female mice after removing the ovaries confirmed the urate-lowering effect of estradiol, and hyperuricemia and estradiol upregulated the expression of intestinal ABCG2. Estradiol has been confirmed to promote urate transport by upregulating ABCG2 expression in intestinal urate excretion models in vivo and in vitro. Estradiol regulates the expression of intestinal ABCG2 through the PI3K/Akt pathway. Our study revealed that estradiol regulates intestinal ABCG2 through the PI3K/Akt pathway to promote urate excretion, thereby reducing serum urate levels.  相似文献   
18.
目的 探讨多药耐药基因(MDR1基因)在人胃癌组织中的表达及其与临床病理的关系。方法 采用逆转录-多聚酶链反应(RT-PCR)法检测了215例手术切除的进展期胃癌组织中的MDR1基因的表达。实验数据采用SAS软件中的χ^2检验和Fisher’s exact P做统计学处理。结果 MDRI基因的阳性率为31.63%(68/215),与年龄、性别、组织学类型、分化程度、淋巴结转移、Borromann分型及TNM分期等无关,但在分化差的肿瘤中有增高趋势,如黏液腺癌及印戒细胞癌中达41.67%及50.00%。结论 化疗前胃癌组织中MDRI基因即存在较高的表达率,这为选用化疗药物和MDR逆转剂提供了参考指标,但不能作为制定化疗方案的唯一指标。  相似文献   
19.
The relevance of Tregs in the induction of tolerance against corneal allografts has been well established. Although it is well known that the conversion of Tregs into effector-like cells contributes to the loss of corneal immune privilege, the underlying mechanism is still not fully understood. Using heterologous penetrating keratoplasty model, we found that Tregs from corneal allograft rejected mice (inflam-Tregs) exhibit impaired function and characteristics of effector T cells. Further study showed that the expression of NF-κB c-Rel, a key mediator of effector T cell function, was significantly increased in inflam-Tregs. Mechanistic study revealed that elevated NF-κB c-Rel level in inflam-Tregs impaired Treg function through the promotion of inflammatory cytokine production and glycolysis. More importantly, we demonstrated that targeting NF-κB c-Rel was able to improve the immune suppressive function of inflam-Tregs in vitro and enhance the potential of them to suppress corneal transplantation rejection. Therefore, our current study identified NF-κB c-Rel as a key mediator of the conversion of Tregs into effector-like cells when under inflammatory environment.  相似文献   
20.
BackgroundHuman papillomavirus (HPV) vaccine has been increasingly discussed in mainland China since its first approval in 2016. To date, nearly all studies assessing HPV vaccine perceptions and attitudes were implemented during pre-licensure period. Therefore, the nationwide post-marketing survey was conducted to update knowledge, attitudes and practice on HPV vaccine among general population in mainland China.MethodsParticipants aged 18–45 years living in mainland China were recruited in April 2019 by multi-stage non-randomized sampling. Sociodemographic factors, HPV and HPV vaccine related awareness, knowledge, attitudes, vaccine uptake and potential obstacles were assessed in questionnaires. Bivariate analysis and multivariate regression were used to identify disparity among subgroups with different sociodemographic characteristics.Results4,000 women (32.1 ± 7.81y) and 1,000 men (31.8 ± 7.96y) were included in final analysis. Less than one third of participants had heard of HPV (female: 31%; male: 22%) and HPV vaccine (female: 34%; male: 23%). Knowledge score was also unfavorable on HPV (female: 3 out of 13; male: 1.8 out of 13) and HPV vaccine (female: 3 out of 6; male: 2 out of 5). Only 3% females had been vaccinated three years after HPV licensure in China, although willingness to get vaccinated among those unvaccinated were high (mean willingness score ± SD: female: 3.3 ± 0.97; male: 3.0 ± 0.98). Industry of employment and household income were the major factors related to awareness and knowledge of vaccine, whereas HPV and HPV vaccine awareness were key influential factors for willingness. The main obstacles of vaccination were safety concerns, lack of knowledge, and high price of HPV vaccines.ConclusionsFindings highlight a lack of vaccine awareness, knowledge, and poor uptake in mainland China and underscore the necessity of health education campaigns. The identified priority groups, contents to be delivered and practical obstacles could furthermore provide insight into health education to reduce disparities and accelerate HPV vaccine roll-out in China.  相似文献   
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