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61.
AIMS/DESIGNS: As part of the Early Developmental Stages of Psychopathology (EDSP) study, results from the baseline cross-sectional assessment of DSM-IV alcohol disorders are presented for a sample of 14-24-year-olds residents in Munich, Germany (N = 3021; 71% response rate). FINDINGS: Life-time prevalence of DSM-IV alcohol abuse (men: 15.1%; women; 4.5%) was found to be considerably more prevalent than dependence (men: 10.0%; women 2.5%) with few cases among respondents younger than 16 years of age; 12-month prevalence of abuse was 8.4% among men and 2.7% among women and of dependence was 7.3% among men and 2.2% among women. Results show that peak incidence of alcohol disorders occurs at 16-17 years of age and that early initiation into alcohol use is associated with an increasing odds of disorder onset, especially for dependence among women. Exploratory analysis of retrospectively assessed diagnostic stability show: a temporal progression to abuse and then dependence, that nearly half of past abuse diagnoses are in remission, abuse remission is more common than progression to dependence, and dependence is highly persistent, especially among women. CONCLUSIONS: Alcohol disorders are frequent in adolescent and young adults being characterized by transient abuse and less prevalent but persistent dependence syndromes. The relatively high prevalence of dependence diagnoses in this young population wit few years of alcohol use is discussed with regard to the clinical validity of DSM-IV criteria in adolescents and young adults. 相似文献
62.
CB Peterson JE Mitchell S Engbloom S Nugent MP Mussell JP Miller 《Canadian Metallurgical Quarterly》1998,24(2):125-136
A new enzymatic assay for selectively measuring conjugated bilirubin concentration in serum with use of bilirubin oxidase (BOD) has been developed. At pH 5.5 BOD can oxidize only conjugated bilirubin in the presence of reagents such as sodium fluoride and N-acetylcysteine which can decrease BOD reactivity to unconjugated bilirubin and bilirubin covalently bound to albumin (delta bilirubin). The resulting decrease in absorbance at 450 nm is linearly related to the concentration of conjugated bilirubin in serum. The BOD in this new assay was confirmed to oxidize conjugated bilirubin, and neither unconjugated nor delta bilirubin, based on both its reactivity to unconjugated bilirubin and HPLC results. This assay was found to give satisfactory results, such as in terms of the range of measurement, the reproducibility of the results, the lack of interference with coexisting substances in serum and the stability of the reagent solutions, in practical applications. The serum conjugated bilirubin concentrations determined using this assay correlate well with those determined by the HPLC analysis. This assay can be used for accurate monitoring of changes in the conjugated bilirubin concentration in patient sera. These findings suggest that the conjugated bilirubin assay is useful for fractional determination of bilirubin in icteric sera. 相似文献
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CB Lazier M Wiktorowicz GE DiMattia DA Gordon R Binder DL Williams 《Canadian Metallurgical Quarterly》1994,106(1-2):187-194
Estrogen regulates the hepatic synthesis of a variety of proteins required for egg yolk production in oviparous vertebrates. In chickens, two of these proteins, apolipoprotein (apo) B and apoII, comprise the major protein components of specialized very low density lipoprotein particles that transport triacylglycerols and cholesterol to the developing egg yolk. In the adult, apoB is synthesized constitutively in liver, small intestine, and kidney but is estrogen-responsive only in the liver. In this work we have examined the embryonic expression of the apoB and apoII genes in yolk sac, liver, kidney, and small intestine. The 14 kb apoB mRNA was first detected at day 3 of development in vascular yolk sac, a tissue involved in the transfer of yolk lipids into the embryonic circulation. Constitutive apoB mRNA expression was detectable in liver at day 6.5 and in kidney at day 7.5, but in intestine was barely detectable before hatching. The hepatic apoB gene acquired estrogen-responsiveness at day 6.5 and its hormone-dependent expression increased throughout development in concert with the estrogen-responsive expression of the apoII gene. In contrast, the constitutively expressed apoB gene in kidney remained unresponsive to estrogen. Surprisingly, the apoII gene was found to be responsive to estrogen in both the embryonic kidney and small intestine. ApoII mRNA induction by estrogen in kidney at day 11 was at 10% of the level in the liver but estrogen-responsiveness decreased later in development and was low in the adult.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
64.
A method for the simultaneous determination of residues of 17 beta-trenbolone and 17 beta, 19-nortestosterone and their epimers in animal tissues is described, involving immunoaffinity chromatography clean-up and high-performance liquid chromatography with dual-wavelength UV detection. The method has been validated at 2 micrograms/kg in pig and cattle liver and corned beef with recoveries of 41% upwards. The method has been applied to the determination of incurred residues of 19-nortestosterone and trenbolone. Various alternative extraction steps for incurred trenbolone have been investigated, including direct extraction, protease digestion, heating and ultrasonic probe treatment. Glucuronidase digestion has been shown to be the most effective method for this analyte. 相似文献
65.
S Ganesh CF Sier MM Heerding JH van Krieken G Griffioen K Welvaart CJ van de Velde JH Verheijen CB Lamers HW Verspaget 《Canadian Metallurgical Quarterly》1997,75(12):1793-1801
Despite the advances in pre-, peri- and post-operative medical care of colorectal carcinoma patients, the prognosis has improved only marginally over recent decades. Thus, additional prognostic indicators would be of great clinical value to select patients for adjuvant therapy. In previous studies we found that colorectal carcinomas have a marked increase of the urokinase-type of plasminogen activator (u-PA), and the inhibitors PAI-1 and PAI-2, whereas the tissue-type plasminogen activator (t-PA) is found to be decreased in comparison with adjacent normal mucosa. In the present study we evaluated the prognostic value of several plasminogen activation parameters, determined in both normal and carcinomatous tissue from colorectal resection specimens, for overall survival of 136 Dukes' stage B and C colorectal cancer patients, in relation to major clinicopathological parameters. Uni- and multivariate analyses indicated that a high PAI-2 antigen level in carcinoma, a low t-PA activity and antigen level and a high u-PA/t-PA antigen ratio in adjacent normal mucosa are significantly associated with a poor overall survival. A high ratio of u-PA antigen in the carcinomas and t-PA antigen in normal mucosa, i.e. u-PA(C)/t-PA(N), was found to be predictive of a poor overall survival as well. All these parameters were found to be prognostically independent of the clinicopathological parameters. Multivariate analysis of combinations of these prognostically significant plasminogen activation parameters revealed that they are important independent prognostic indicators and have in fact a better prognostic value than their separate components. Based on these combined parameters, subgroups of patients with Dukes' stage B and C colorectal cancer could be identified as having either a high or a low risk regarding overall survival. In conclusion, these findings emphasize the relevance of the intestinal plasminogen activation system for survival prognosis of patients with colorectal cancer and, in the future, might constitute a patient selection criterion for adjuvant therapy. 相似文献
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67.
The microhaematocrit (MH) technique was used to study the survival of Trypanosoma evansi in blood from two herds of naturally-infected horses. A comparison was made between samples treated with ethylenediaminetetraacetic acid and sodium citrate (alone or with 1% glucose), and sent to the laboratory packed in ice. In general, the number of samples yielding positive results by the MH technique showed the least variation during the first 24-36 h after sample collection. Survival varied with the anticoagulant used, but it declined rapidly from 48 h after collection, although live parasites were still observed in up to 10% of samples until the seventh day. On the basis of the results obtained, the authors recommend the use of sodium citrate in treating equine blood samples for the parasitological diagnosis of T. evansi. 相似文献
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70.
Thuringiensin A, an exotoxin from Bacillus thuringiensis, a constituent of the microbial insectide thuricide has been found to inhibit mitotic spindle, condense and scatter chromosomes. It may therefore be a promizing tool in future cell biological studies. 相似文献