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11.
Eight cultured cell lines were established from human smallcell lung cancers. Every cell line showed the morphologicaland biochemical characteristics of small cell cancer. Changesin cell characteristics were observed in many of these celllines when culture conditions were changed: "oat cell type"changed to "intermediate cell type" and vice versa when serum-freemedium was changed to serum-supplemented medium; a deficiencyof vitamin A in the medium caused a change to squamous cellsand vice versa; and a tumor promoter (teleocidin B) enhancedthe adherence of these cells to the surface of plastic culturedishes. These findings provide evidence that many small celllung cancer cell lines can change their morphology with changesin the environment of the cells.  相似文献   
12.
We evaluated the effects of the seed saponins of Thea sinensisL. on alcohol absorption and metabolism in rats and mice. Anethanolic extract from the seeds of T. sinensis was orally administeredto the rats 1 hr before or 0.5 hr after administration of ethanol(2 g/kg), and the blood ethanol assayed 0.5, 1, 2, 3, and 4hr after ethanol administration. The ethanol level decreasedafter both pie- and post- administration of the extract. Theextract was further purified to obtain a saponin fraction whichwas orally administered to mice 1 hr before ethanol administration.Blood, liver, and stomach were obtained 0, 1, 3, and 6 hr afterethanol administration, and the ethanol, acetaldehyde, acetate,and acetone concentrations in each specimen were measured byhead space gas chromatography. The saponin fraction decreasedthe ethanol levels in the blood and liver but increased thatin the stomach five-fold over the control level, suggestinginhibition of alcohol absorption. The ethanol disappearancetime from the blood was shortened, suggesting the promotionof alcohol disappearance. The acetate and acetone levels wereunaffected. However, the acetaldehyde level decreased in theblood, liver, and stomach. The decreases in the ethanol andacetaldhyde levels in the liver suggested the protective effectsof the seed saponins on the liver. The saponins did not directlyinhibit hepalic alcohol dehydrogenase activity. The seed saponinsof T. sinensis seem to suppress alcohol absorption by slowinggastric emptying and by inhibiting absorption across the cellmembranes of the digestive tract.  相似文献   
13.
目的为了进一步分析合成鱼腥草素的免疫调节作用机理 ,研究合成鱼腥草素对于巨噬细胞呼吸爆发、细胞内钙离子浓度以及T细胞分泌白细胞介素水平的影响。方法巨噬细胞分离自大鼠腹腔灌洗液。以 2′ ,7′ 二氯荧光素二乙酯作为荧光指示剂 ,采用流式细胞术检测巨噬细胞的呼吸爆发。以fura 2作为钙离子荧光指示剂采用荧光分光光度法测定细胞内钙离子浓度。利用淋巴细胞分离液采用密度梯度离心法分离外周血T细胞 ,并用尼龙毛柱加以纯化。用ELISA法测定在亚适剂量ConA、白细胞介素 1α(IL 1α)以及白细胞介素 1β(IL 1β)存在的条件下合成鱼腥草素对白细胞介素 2 (IL 2 )分泌的影响。结果合成鱼腥草素可以刺激巨噬细胞呼吸爆发 ,提高细胞内钙离子浓度水平 ,促进T细胞分泌IL 2。结论合成鱼腥草素可能具有激活巨噬细胞和T淋巴细胞的作用 ,从而部分解释合成鱼腥草素的佐剂作用以及治疗感染性疾病的作用机理。  相似文献   
14.
A case report is presented of a 15-year-old girl with reflex sympathetic dystrophy (RSD). She was referred to hospital because of left upper limb pain. Her left upper limb was cold, edematous and blue with a limited active range of movement. The serum concentration of noradrenaline was lower on the painful side than on the healthy side, and neurotropin, which has an antinociceptive effect to hyperalgesia, was clearly effective. Early diagnosis and management is essential in the treatment of RSD and administration of neurotropin is a useful and non-invasive treatment without severe adverse effects.  相似文献   
15.
Problem drinking is a serious public health problem in the workplace. However, few Japanese epidemiological studies have investigated the occupational characteristics of problem drinking. The purpose of this study is to clarify the occupational risk factors for problem drinking among a Japanese working population. We used data from a random-sampling survey about mental health and suicide, conducted among Hamamatsu City residents aged 15 to 79 yr old during May and June in 2008. The relation between occupational factors and problem drinking was analyzed with multiple logistic regression models stratified by gender. CAGE questionnaire was used to assess problem drinking. With regard to employment types, problem drinkers were more prevalent among self-employed women. With regard to occupational types, clerical and service professions had more problem drinkers of either sex, while administrative/managerial and sales professions had more women with such problem. With regard to company size, male problem drinkers were more prevalent in smaller companies than in larger ones. These results indicate that the prevalence of problem drinkers in the workplace depends on where one works. It is necessary to consider these characteristics to provide effective measures to address problem drinking in the workplace.  相似文献   
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17.
A sensitive sandwich enzyme-linked immunosorbent assay (ELISA) has been established to estimate serum thrombopoietin (TPO) concentrations in healthy volunteers and patients with haemopoietic disorders. The ELISA uses a mouse monoclonal antibody (Ab) as the capture Ab and a biotinylated rabbit polyclonal Ab as the detector. The ELISA was reproducible, highly sensitive and specific for human TPO. The coefficients of intra- and inter-assay variation were from 3.0% to 4.9% and from 5.9% to 6.1%, respectively. The quantitative limit of the ELISA was 0.09 fmol/ml in serum. The quantitative limit was lower than the normal level. The dose–response curves of serum samples from healthy volunteers and patients with haemopoietic disorders were parallel to the standard curves. The ELISA did not cross-react with a variety of blood components and cytokines to produce false-positive results.
The serum TPO concentrations from 29 normal males and 21 females were 0.79 ± 0.35 and 0.70 ± 0.26 fmol/ml, respectively. Serum TPO levels in patients with aplastic anaemia (AA), acute lymphocytic leukaemia (ALL) and essential thrombocythaemia (ET) were measured using the ELISA. The serum TPO levels in the patients with ET ( n  = 6, 2.80 ± 1.55 fmol/ml) were higher than the normal level. The patients with AA ( n  = 7, 18.53 ± 12.37 fmol/ml) and ALL ( n  = 5, 10.36 ± 5.57 fmol/ml) had significantly higher serum TPO levels than normal individuals. These results indicate that the ELISA specific to TPO should prove useful in measuring the TPO concentration in serum samples.  相似文献   
18.
Cellular response to our designed biodegradable polyrotaxanes was investigated in terms of changes in cytoplasmic calcium levels in platelets. The polyrotaxanes regulated thrombin-induced calcium increase in platelets although constituent molecules of the polyrotaxanes showed fewer effects on the intracellular metabolism. Further, an increase in membrane fluidity of red blood cell ghosts was significantly observed by the addition of the polyrotaxanes. Static light scattering study revealed that the polyrotaxanes formed a supramolecular association state in relation to the molecular weight of PEG: a loosely packed association with a specific molecular shape. From these characteristics, it is suggested that supramolecular level interactions between the polyrotaxanes and cell membranes regulate the intracellular metabolism. It is concluded that these biodegradable polyrotaxanes can be feasible as temporarily-controlled bioactivator.  相似文献   
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20.
Cyclic AMP (cAMP) output in the duodenal contents of 11 normal subjects, 18 patients with chronic pancreatitis, six convalescing from acute pancreatitis and five with pancreatic carcinoma was measured after a single dose of pancreozymin and secretin. The technic was indirect, utilizing recovery of duodenal contents by the Dreiling tube rather than direct measurements of fluid that was not contaminated by bile. In all patients groups, cAMP output reached a peak after this stimulation with a concomitant increase of bicarbonate and amylase outputs. A significantly decreased cAMP output was observed in all pancreatic disease groups compared to the normal group. Patients with chronic pancreatitis showed a slightly decreased cAMP output, considerably decreased bicarbonate output and normal amylase output. In acute pancreatitis cAMP output was reduced with normal bicarbonate and amylase outputs. In pancreatic carcinoma cAMP decreased significantly, bicarbonate output was moderately reduced and amylase output was normal. cAMP output in all groups studied did not correlate with either bicarbonate output or amylase output.  相似文献   
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