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排序方式: 共有1772条查询结果,搜索用时 46 毫秒
1.
用放射配体结合分析法分别测定了正常组、特布他林组、特布他林十曲尼司特组豚鼠的肺组织β受体最大结合力和解离常数,结果显示:给特布他林后豚鼠肺组织β受体发生明显的向下调节.曲尼司特可预防此向下调节的发生. 相似文献
2.
Reframing climate change as a public health issue: an exploratory study of public reactions 总被引:1,自引:0,他引:1
Edward W Maibach Matthew Nisbet Paula Baldwin Karen Akerlof Guoqing Diao 《BMC public health》2010,10(1):299
Background
Climate change is taking a toll on human health, and some leaders in the public health community have urged their colleagues to give voice to its health implications. Previous research has shown that Americans are only dimly aware of the health implications of climate change, yet the literature on issue framing suggests that providing a novel frame - such as human health - may be potentially useful in enhancing public engagement. We conducted an exploratory study in the United States of people's reactions to a public health-framed short essay on climate change. 相似文献3.
Itiswellknownthatcertaincytokinesplayapivotalroleinthedevelopmentoftraumaandshock.Tumornecrosisfactor(TNF)isapolypep-tiedcytokinesynthesizedinmonocytesandmacrophagesinresponsetolipopolysaccharide(LPS)stimulation-TherelationshipbetweenTNFandendotoxic-septicshockbecomesafocusoftheresearchofshockmediators[1'2].Alargeamountofexperimentalandclinicaldata[3-9JsuggestthatTNFplaysanimportantroleinthepathogenesisofendotoxic-septicshockbuttheprecisemechanismandtherelationshipofTNFtoshockseverityrem… 相似文献
4.
Yanke Yu Wen Zhu Huiling Diao Chunxian Zhou Fanqing F Chen Jun Yang 《Toxicology in vitro》2006,20(6):959-965
Comet assay is a useful technique in the detection of DNA damages, particularly DNA strand breaks; and it has been utilized to show that a potent carcinogen N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), can induce such damages. Recently, gammaH2AX foci formation has been suggested as another sensitive way to detect DNA double strand breaks (DSBs). However, there is no systematic comparison being conducted to evaluate the consistency of these two methods. Using MNNG as a model chemical, the sensitivity of neutral comet assay and gammaH2AX foci formation in detecting MNNG-induced damage was studied. It was found that at concentrations of 0.1 and 1 microg/ml, both methods can detect MNNG-induced damage in human amnion FL cells. However, at 0.1 microg/ml, comet assay revealed more percentage of cells with DNA damage than gammaH2AX fluorescence revealed. On the other hand, while gammaH2AX foci were readily formed at very early times by 10 microg/ml MNNG treatment, neutral comet assay did not detect any significant DNA damage at the same time points. In addition, 10 microg/ml MNNG induced a distinct whole nuclei staining pattern of gammaH2AX, a type of DNA damage which was not detected by neutral comet assay but could be detected by alkaline comet assay. Therefore, gammaH2AX may be used as a sensitive indicator for DNA damage. 相似文献
5.
140 patients with brain tumor were treated by CT-guided stereotactic injections of radionuclides, such as Aurum-198 (198 Au), Phosphorus-32 (32 P) and Yttrium-90 (90Y). Of these patients aged from 3 to 67 years (average 37), 64 were male and 76 female. Astrocytoma was found in 75 patients, craniopharyngioma in 46, metastatic carcinoma in 7, meningioma in 5, germinoma in 4 and pituitary adenoma in 3. The tumors were located in the deep part or functionally critical area of the brain. After 267 times of injection of colloidal isotopes, no major adverse effects or complications occurred. Follow-up for 6 to 48 months showed improvement in symptoms in 104 (74.3%) patients and CT scanning showed the diminished tumors.
相似文献
6.
本文采用国产原料试制氧氟沙星薄膜包衣片,并与日本第一制药株式会社生产的片剂进行了体外溶
出度、休内相对生物利用度比较。休内血清药物浓度采用HPLC法测定。自制片剂与进口片剂生物等效。 相似文献
7.
相对于我国企业改革的发展,医疗卫生单位后勤管理与改革不仅起步较晚,而且力度不大,步伐不快。以往的医疗卫生单位后勤往往面面俱到,造成了严重的经济负担和社会资源的浪费。因此,医疗卫生单位后勤改革势在必行。 相似文献
8.
概述光学塑料的基本材料,讨论塑料镜片材料的主要品种及其应用,并着重分析影响塑料镜片材料性能的主要因素及其发展趋势。 相似文献
9.
Osteopontin affects the persistence of beta-glucan-induced hepatic granuloma formation and tissue injury through two distinct mechanisms 总被引:4,自引:0,他引:4
Morimoto J Inobe M Kimura C Kon S Diao H Aoki M Miyazaki T Denhardt DT Rittling S Uede T 《International immunology》2004,16(3):477-488
Osteopontin (OPN) plays a pivotal role in various immune responses and inflammatory diseases. OPN is expressed in various granulomatous diseases; however, the cellular and molecular role of OPN in these diseases is not well known. We analyzed the role of OPN in a beta-glucan-induced hepatic granuloma model. First, we found that neither OPN deficiency nor overexpression of OPN affected the number and the size of hepatic granulomas at day 7, indicating that OPN is not involved in the formation of hepatic granulomas at the early stages. Importantly, OPN did not influence the liver tissue damage as defined by alanine aminotransferase and aspartate aminotransferase levels at early stages. Second, OPN deficiency resulted in the reduction of IL-12 and IFN-gamma production at early stages. Third, at late stages, OPN deficiency resulted in a decrease in the number and size of hepatic granulomas, and a reduction of liver tissue injury. This was due to the reduction of the cellular recruitment including macrophages, CD4 T cells and dendritic cells into the liver, and the reduction of tumor necrosis factor (TNF)-alpha production in the liver. In contrast, overexpression of OPN resulted in the persistence of granuloma formation. These data suggest that OPN affects the persistence of hepatic granuloma formation. Our results indicate that OPN up-regulates the production of IL-12 and IFN-gamma within the granulomas at early stages, and OPN has an additional role in the regulation of cellular recruitment and TNF-alpha production at late stages that determine the severity of liver tissue injury. 相似文献
10.
目的:研究干扰素γ(IFN-γ)对博莱霉素诱导的大鼠肺纤维化实验模型肺泡炎和肺纤维化的影响,并探讨其对肺纤维化影响的可能机制。方法:60只SD大鼠随机分为正常对照组(N组)、模型对照组(M组)和干扰素γ组(R组),每组各20只大鼠。于造模后3、7、14、28天分批处死动物,留取肺组织,观察肺泡炎和肺纤维化的程度,测定肺组织中的羟脯氨酸含量、IFN-γmRNA、转化生长因子β(TGF-β)mRNA的表达。结果:M组、R组大鼠肺泡炎3、7、14、28天均较N组严重,7天时最重,R组14天时肺泡炎显著高于M组;M组、R组肺纤维化评分及肺羟脯氨酸含量14、28天均高于N组,于28天最重;R组肺组织IFN-γmRNA表达3、7、14、28天均显著高于M组;R组肺组织中TGF-βmRNA表达在3天显著高于M组(P〈0.05)。结论:在博莱霉素诱导大鼠肺纤维化早期给予干扰素γ并不能减轻肺部炎症和肺纤维化,可能与其促进肺组织IFN-γ、TGF-β基因表达有关。 相似文献