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Leptin is a newly found hormone secreted by adipocytes that regulates food intake, thermogenesis, and body fat. We measured plasma leptin levels in 103 patients with chronic renal failure treated by hemodialysis and 167 age- and gender-matched healthy control subjects to examine the impact of renal failure on plasma leptin levels and the influence of leptin on body composition measured by dual-energy X-ray absorptiometry. Hemodialysis patients showed a significant decrease in both body fat mass and lean body mass compared with those of the control subjects. Plasma leptin was significantly elevated in the hemodialysis group over the controls. In both groups, leptin was higher in female than male subjects, and it correlated positively with percent body fat. The subjects were divided into six categories according to percent body fat, and plasma leptin levels were compared between the two groups in the same category. Leptin of hemodialysis patients was significantly higher than that of the control subjects in the percent body fat categories of 30 or greater, whereas there was no statistically significant difference in leptin concentrations in the lower percent body fat categories. This was also true in the comparison in each gender, and leptin levels in female subjects showed a more remarkable difference between the hemodialysis and control groups in obese categories. Multiple regression analysis in all subjects indicated that plasma leptin levels were independently affected by percent body fat, plasma insulin concentration, gender, and renal failure. The positive impact of renal failure on leptin remained significant in the subjects with percent body fat of 30 or greater in the multiple regression model, whereas it was no longer significant in the remaining lean subjects. In multiple regression analysis of factors affecting fat mass index and lean mass index, leptin level was selectively associated with fat mass index, but not with lean mass index, regardless of percent body fat ranges. These results indicate that renal failure is an important factor affecting plasma leptin levels, especially in obese female subjects, and that hyperleptinemia was closely related to fat mass but not to lean body mass in hemodialysis patients.  相似文献   
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The anti-allergic activity of bryonolic acid (1) isolated from the cultured cells of Luffa cylindrica L. (Cucurbitaceae) was compared with that of glycyrrhetinic acid (2), the aglycone of glycyrrhizin from licorice. Compound 1, when administered to rats intraperitoneally at a dose of 600 mg/kg, inhibited homologous passive cutaneous anaphylaxis more strongly than 2 at the same dose. Compound 1 also significantly inhibited delayed hypersensitivity in mice which could not be inhibited by 2. In contrast to 2, 1 showed not only little toxicity but no visible side effects on mice, without impairing the activity of the hepatic enzyme (4,5 beta-dihydrocortisone:NADP+ delta 4-oxidoreductase) involved in steroid catabolism.  相似文献   
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Hepatocyte regeneration has been widely investigated, with the mitotic index and the incorporation of [3H]thymidine being used as regeneration markers. We focused on the induction of DNA replication enzymes, particularly DNA polymerases (pol) α, δ, and ε. Using rat models, we have shown that the activity of pol α in crude liver extract well represents the regenerating capacity of hepatocytes. Using pol α as an indicator, we analyzed liver regeneration in rat models under various conditions: obstructive jaundice, external or internal biliary drainage, and the obstruction of portal vein branches. It has been revealed that the ligation of the common bile duct alone induces a certain amount of hepatocyte proliferation. It was striking that external biliary drainage suppressed regeneration capacity in cholestatic rat liver after partial hepatectomy. The strong regeneration in nonligated lobes induced by portal branch ligation was similar to the liver regeneration seen after partial hepatectomy with respect to the induction of DNA polymerases. Taken together, the aspects of DNA replication, particularly the induction of DNA polymerases, may contribute to shedding new light on the regeneration of human liver. This work was supported in part by a Grant-in-Aid for General Scientific Research and for Cancer Research from the Ministry of Education, Science and Culture, Japan, and by grants from the Uehara Memorial Foundation  相似文献   
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Off-pump surgery was performed in a patient with post-infarction angina complicated with aneurysmal coronary-pulmonary arterial fistula. Epicardial echocardiography localized the artery feeding the fistula in the myocardium, which had not been revealed by visual inspection, palpation, or transesophageal echocardiography. The patient underwent off-pump coronary artery bypass grafting concomitant with aneurysmectomy. The feeding arteries were dissected easily using a Harmonic Scalpel and ligated. The flow in the aneurysm disappeared immediately and aneurysmectomy was performed without bleeding.  相似文献   
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C2H2-type zinc finger genes comprise one of the largest genefamilies in the human genome. These proteins are involved ingenetic regulation and development and are quite conserved throughoutevolution. The finger domains commonly contain the small linkerpeptide TGEKP between some finger units. Here, we report theisolation of 133 human zinc finger cDNAs, of which 118 are novel.These clones were isolated from human brain cDNA libraries usingoligonucleotide hybridization followed by expressed sequencetag (EST) analysis, sequencing from the conserved linker regionusing degenerate oligonucleotide primers. This directed partialsequencing approach to cDNA isolation and characterization,signature sequencing, combines the speed of EST automatic sequencingwith the focus of specific cDNA family analysis. Signature sequencingminimizes the generation of less informative random EST sequencesand provides a unique relative position for sequence comparison.We also show that there is an even distribution of these RNA5from this brain cDNA library, and that these cDNAs contain N-terminaldomains found in other zinc finger genes. This rapid focusedsequencing approach should be applicable to any family of cDNAscontaining short conserved signature peptide sequences.  相似文献   
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Background: A recent study reported that patients with delirium responded well to the administration of atypical antipsychotic agents. In the present study we administered quetiapine to patients with delirium and obtained good results. Methods: This study included 24 patients (10 men, 14 women), referred to the psychiatry department during admission to other hospital departments, who were diagnosed as having delirium according to the diagnostic and statistical manual of mental disorders (4th edition) (DSM‐IV) between April 2001 and September 2002. The mean age of the patients was 76.5 years (men 71.0 years; women 80.5 years). An initial dose of quetiapine was established at 25–50 mg/day. Depending on the symptoms, the dose and frequency were increased as required. According to Trzepacz's delirium rating scale (DRS), the treatment response was evaluated prior to the administration of quetiapine and 1, 3, 5 and 7 days after administration began. Results: Prior to the administration of quetiapine, the mean DRS score was 18.1. The mean scores were 12.2, 10.8, 9.7 and 8.9 after 1, 3, 5 and 7 days of quetiapine administration, respectively. These values were significantly lower than the value before administration (P < 0.001). Seven days after the administration of quetiapine commenced, the total DRS score was lower than the cutoff point (12) in 20 patients (83.3%). In 18 patients (75.0%), delirium was clinically relieved. Doses ranged from 25 mg/day to 125 mg/day, with a mean dose of 54.7 mg/day. With respect to the administration method, the majority of patients (i.e. 13 patients) received quetiapine once per day (after dinner). Somnolence was observed in three patients as a side‐effect of quetiapine administration. However, this side‐effect improved after 1–2 days, without decreasing the dose. Conclusions: Quetiapine may be useful for controlling delirium and concerning side‐effects and extrapyramidal symptoms were not recorded in the present study. Thus, it is appropriate to trial quetiapine in the treatment of delirium.  相似文献   
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Uncertainties remain as to whether breastfeeding is protective against childhood allergic disorders. Positive relationships of breastfeeding with asthma and atopic eczema were observed in two previous Japanese studies. This cross-sectional study investigated the association between the feeding pattern after birth and the prevalence of allergic disorders during the past 12 months in Japanese schoolchildren. Study subjects were 24,077 children aged 6-15 yr in Okinawa. The outcomes were based on diagnostic criteria from the International Study of Asthma and Allergies in Childhood. Allowance was made for age, sex, number of siblings, smoking in the household, paternal and maternal history of asthma, atopic eczema, and allergic rhinitis, and paternal and maternal educational level. Breastfeeding, regardless of exclusivity, for 13 months or longer and exclusive breastfeeding for 4-11 months were independently associated with a higher prevalence of atopic eczema, particularly among children without a parental allergic history. A clear positive dose-response relationship was observed between prolonged duration of breastfeeding, regardless of exclusivity, but not exclusive breastfeeding, and the prevalence of atopic eczema. We found a significant positive trend for atopic eczema across the three categories (formula milk, partial and exclusive breastfeeding) in the first 4 months of life although the odds ratio for exclusive breastfeeding was not statistically significant. No material association was found between the feeding pattern after birth and the prevalence of wheeze or allergic rhinoconjunctivitis. Prolonged breastfeeding may be associated with a higher prevalence of atopic eczema in Japanese children.  相似文献   
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