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81.
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83.
The expression levels of mRNAs for MDR1 (P-glycoprotein), multidrug resistance-associated proteins (MRP1, MRP2), and cytochrome P450 3A (CYP3A) in Caco-2 cells were quantitatively compared with those in human duodenal enterocytes, normal colorectal tissues, and colorectal adenocarcinomas. Caco-2 cells (passages 36-88) were kindly supplied by several laboratories in Japan. Human duodenal enterocytes were obtained from five healthy male volunteers. Normal colorectal tissues and colorectal adenocarcinomas were simultaneously obtained from seven patients with primary colorectal adenocarcinoma. MDR1, MRP1, MRP2, and CYP3A mRNA levels were determined by real-time quantitative polymerase chain reactions (PCR). Relative concentrations of mRNAs for target proteins (MDR1, MRP1, MRP2, and CYP3A) and glyceraldehyde-3-phosphate dehydrogenase in Caco-2 cells were 1.00 +/- 0.15, 1.02 +/- 0.06, 0.94 +/- 0.10, and 0.68 +/-0.60, respectively, and those in human enterocytes were about 12-, 3-, 7-, and 8000-fold higher than in the Caco-2 cells, respectively. In contrast, MDR1, MRP1, and CYP3A mRNA levels in Caco-2 cells were comparable to those in normal colorectal tissue and colorectal adenocarcinoma.  相似文献   
84.
Abstract: Fullerene‐C60 (C60) is mainly applied in the aqueous phase by wrapping with water‐soluble polymer or by water‐solublizing chemical‐modification, whereas C60 dissolved in oil is scarcely applied; still less explicable is its toxicity. We dissolved C60 in squalane at near‐saturated or higher concentrations (220–500 ppm), named LipoFullerene (LF‐SQ), and examined its biological safety. LF‐SQ was administered at doses of 0.49–1000 µg/ml to fibroblast cells Balb/3T3, and showed that cell viability was almost equal to that of the control regardless of the UVA‐ or sham‐irradiation, indicating no phototoxicity. Reverse mutation by LF‐SQ was examined on four histidine‐demanding strains of Salmonella typhimurium and a tryptophan‐demanding strain of Escherichia coli. As for the dosages of LF‐SQ (313–5000 µg/plate), the dose‐dependency of the number of reverse mutation colonies of each strain did not show a marked difference when compared with the negative control, regardless of the metabolic activation, in contrast to twice or more differences for five positive controls (sodium azide, N‐ethyl‐N′‐nitro‐N‐nitrosoguanidine, 2‐nitrofluorene, 9‐aminoacridine, and 2‐aminoanthracene). In human skin biopsy built in a diffusion chamber, C60 permeated into the epidermis at 33.6 nmol/g tissue (24.2 ppm), on administration with LF‐SQ containing 223 ppm of C60, but not detected in the dermis even after 24 hrs, as analysed by HPLC. It is presumed that LF‐SQ can permeate into the epidermis via the corneum but can not penetrate the basement membrane, and so can not reach into the dermis, suggesting no necessity for considering a toxicity of C60 due to systemic circulation via dermal veins. Thus, C60 dissolved in squalane may not give any significant biological toxic effects such as photocytotoxicity, bacterial reverse mutagenicity, and permeability into the human skin.  相似文献   
85.
OBJECTIVE: To document the effects of propofol on the hemodynamic and inflammatory responses to endotoxemia in an animal model. DESIGN: Randomized, prospective laboratory study. SETTING: University experimental laboratory. SUBJECTS: Thirty-two male rats. INTERVENTIONS: The animals were randomly assigned to one of four groups: a) endotoxemia group (n = 8), which received intravenous Escherichia coli endotoxin (15 mg/kg over 2 mins); b) control group (n = 8), which was treated identically to the endotoxemia group except for the substitution of 0.9% saline for endotoxin; c) propofol group (n = 8), which was treated identically to the control group but also received propofol (10 mg/kg bolus, followed by infusion at 10 mg/kg/hr) immediately after the injection of 0.9% saline; and d) propofol-endotoxemia group (n = 8), which was treated identically to the endotoxemia group with the additional administration of propofol (10 mg/kg bolus, followed by infusion at 10 mg/kg/hr) immediately after endotoxin injection. MEASUREMENTS AND MAIN RESULTS: Hemodynamics, arterial blood gases, and acid-base status were recorded and the blood propofol concentrations and plasma cytokine concentrations were measured during the 5-hr observation. Microscopic findings of lung tissue for each group were obtained at necropsy. The systolic arterial pressure and heart rate of the propofol-endotoxemia group were similar to those of the endotoxemia group. The increases in the plasma cytokine (tumor necrosis factor, interleukin-6, and interleukin-10) concentrations, in the base deficit, and in the infiltration of neutrophils in the air space or vessel walls of the lungs were attenuated in the propofol-endotoxemia group compared with the endotoxemia group. CONCLUSIONS: Propofol attenuated cytokine responses, base deficit, and activation of neutrophils to endotoxemia. These findings suggest that propofol may inhibit inflammatory response and prevent the development of metabolic acidosis during endotoxemia.  相似文献   
86.
This study was designed to investigate if the components of the QT interval after a pause are influenced by the preceding pacing cycle length. Ten patients (seven women and three men; age 79 +/- 9 years, means +/- SD) with complete atrioventricular block or sick sinus syndrome whose own heart rate was < 40 beats/min were examined. All patients had already undergone implantation of a permanent pacemaker. Ventricular pacing protocol was performed with simultaneous recording of a 12-lead electrocardiogram. One set of regular stimuli for 30 seconds (S1) with a variable cycle length (1,000, 700, and 400 ms) was followed by a single stimulus (S2) with a fixed coupling interval of 1,500 ms. QT intervals in response to the last S1 (S1-QT) and S2 (S2-QT) were measured. The QT interval was divided into two components, the interval from start of Q wave to the peak of T wave (QaT) and that from the peak to end of T wave (Tae). The S2-QT and S1-QT interval shortened in association with a decrease in the S1S1 interval. The abbreviation of S2-QT interval was not associated with a significant change in the Tae interval. The results demonstrated that the QT interval after a pause shortened by reducing the preceding pacing cycle length. This shortening is probably due to a homogenous abbreviation of action potential duration across the ventricular wall.  相似文献   
87.
INTRODUCTION: There is some evidence for the efficacy of acupuncture in chronic neck pain (CNP) treatment, but it remains unclear which acupuncture modes are most effective. Objective was to evaluate the effects of trigger point acupuncture on pain and quality of life (QOL) in CNP patients compared to three other acupuncture treatments (acupoints, non-trigger point and sham treatment). METHODS: Forty out-patients (29 women, 11 men; age range: 47-80 years) from the Department of Orthopaedic Surgery, Meiji University of Oriental Medicine, with non-radiating CNP for at least 6 months and normal neurological examination were randomised to one of four groups over 13 weeks. Each group received two phases of acupuncture treatment with an interval between them. The acupoint group (standard acupuncture; SA, n=10) received treatment at traditional acupoints for neck pain, the trigger point (TrP, n=10) and non-trigger point (non-TrP, n=10) groups received treatment at tenderness points for the same muscle, while the other acupuncture group received sham treatments on the trigger point (SH, n=10). Outcome measures were pain intensity (visual analogue scale; VAS 0-100mm) and disease specific questionnaire (neck disability index; NDI, 60-point scale). RESULTS: After treatment, the TrP group reported less pain intensity and improved QOL compared to the SA or non-TrP group. There was significant reduction in pain intensity between the treatment and the interval for the TrP group (p<0.01, Dunnett's multiple test), but not for the SA or non-TrP group. CONCLUSION: These results suggest that trigger point acupuncture therapy may be more effective on chronic neck pain in aged patients than the standard acupuncture therapy.  相似文献   
88.
Decreased levels of IL-1 alpha and beta in psoriatic lesional skin   总被引:1,自引:0,他引:1  
Interleukin 1 (IL-1), which mediates a wide range of biological activities, is thought to play an important role in many inflammatory and immunologic diseases. Normal human epidermal keratinocytes constitutively produce IL-1. Based on our previous data indicating decreased IL-1 activity in psoriatic scale extracts, in the present study, we measured immunoreactive IL-1 alpha and beta levels in the suction blister fluids as well as in the psoriatic scale extracts using enzyme immunoassay for IL-1 alpha and beta. The results showed that although similarly low levels of IL-1 alpha were detectable in the suction blister fluid from normal and psoriatic lesional skin, and that no IL-1 beta was found in most of the blister fluids, indicating that IL-1 alpha is major IL-1 species produced by human skin. As compared to those in the blister fluids, IL-1 alpha levels in the horny tissue extracts were found to be much higher, and they were significantly higher in the orthokeratotic stratum corneum extracts than in the psoriatic scale extracts. However, gel filtration of the orthokeratotic horny tissue extracts demonstrated that constituents for immunoreactive IL-1 alpha and beta were quite variable depending upon the source of the horny tissues. The present study has confirmed that IL-1 levels in the psoriatic scale extracts are decreased when compared with those in the orthokeratotic horny tissue possibly due to an increased epidermal proliferation activity associated with its high turnover rate. The role of IL-1 psoriatic lesions remains unknown.  相似文献   
89.
BACKGROUND/AIMS: This study was performed to evaluate the efficacy and safety of percutaneous microwave coagulation therapy for superficial hepatocellular carcinoma located on the surface of the liver. METHODOLOGY: Among 58 cirrhosis patients with 71 hepatocellular carcinomas measuring < or = 20 mm in greatest dimension, 18 patients had a solitary superficial lesion located on the liver surface (superficial hepatocellular carcinoma group) and the other 40 patients had 53 lesions that were not in contact with the liver surface (non-superficial hepatocellular carcinoma group). All patients were treated by percutaneous microwave coagulation therapy alone and the response was assessed by using contrast-enhanced CT. The survival, tumor recurrence, and adverse effects were compared between the superficial and non-superficial hepatocellular carcinoma groups. RESULTS: The 4-year survival rates of the superficial hepatocellular carcinoma group (64.2%) and the non-superficial hepatocellular carcinoma group (58.9%) were not significantly different, and neither were the 4-year local recurrence rates (27.1% vs. 29.8%). Although there was a significantly higher incidence of severe pain during microwave irradiation in the superficial hepatocellular carcinoma group (23/47) when compared with the non-superficial hepatocellular carcinoma group (25/148), there were no differences between them in the incidence of fever or the changes in liver function after treatment. There were no serious adverse effects, such as hemorrhage or tumor cell seeding, in either group. CONCLUSIONS: Percutaneous microwave coagulation therapy can be performed safely, even in patients with superficial hepatocellular carcinoma and cirrhosis, so this method is effective for treating hepatic neoplasms regardless of the tumor location.  相似文献   
90.
A highly sensitive sandwich enzyme immunoassay for human interleukin-1 beta (hIL-1 beta) in urine is described. Rabbit anti-hIL-1 beta IgG-coated polystyrene balls were incubated with urine samples and subsequently with affinity-purified rabbit anti-hIL-1 beta Fab'-horseradish peroxidase conjugate. After washing, the peroxidase activity bound to the polystyrene ball was assayed by fluorimetry using 3-(4-hydroxyphenyl)propionic acid as a substrate. The detection limit of hIL-1 beta was 0.5 pg/tube (30 amol/tube) or 5 ng/1 of urine when 0.1 ml of urine sample was used. The molecular weight of hIL-1 beta in normal urine was shown to be 17,000 by gel filtration, and levels of urine hIL-1 beta in healthy subjects aged 19-87 yr were 0-146 ng/1 or 0-88 ng/g of creatinine.  相似文献   
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