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71.
Comparison of two ELISAs for the determination of Hsp70 in serum 总被引:2,自引:0,他引:2
We have compared a previously developed in-house Sandwich-ELISA with a commercial kit for the determination of heat shock protein (Hsp) 70 in serum. Samples from 64 participants were tested and there was a significant correlation between results obtained using the two assays (r = 0.807, p < 0.0001). Additionally, when ranking samples on a categorical scale, the agreement was good (72%). In the commercial test system Hsp70 was detectable in 42 (66%) of the sera, compared with 61 (95%) in the in-house ELISA method. The three samples with undetectable levels of Hsp70 in the in-house ELISA were among the 22 samples with undetectable levels of Hsp70 in the commercial ELISA kit. The apparent serum concentrations detected were different in the two systems. This dissimilarity can be ascribed to differences in the matrix used. We conclude that the in-house ELISA is more economical and performs well when measuring physiologically high, as well as low, concentrations of Hsp70. 相似文献
72.
Alexander E. Karu Tony H. Lin Leo Breiman Mark T. Muldoon Jean Hsu 《Food and Agricultural Immunology》1994,6(4):371-384
Quantitative competition immunoassays with appropriate combinations of antibodies give consistent dose‐response patterns which may be used to identify and estimate amounts of cross‐reacting compounds. Previously reported methods of analyzing cross‐reaction patterns include multiple regression, principal components analysis and minimum estimates of variance (MEV). Four other techniques which are preferable in theory have been surveyed: discriminant analysis (DA), maximum likelihood estimates (MLE), classification and regression trees (CART), and computational neural networks (NN). MLE and simple back‐propagation neural networks can estimate the concentration, as well as the identity, of individual compounds. These four methods worked well with unfitted, unscaled data from monoclonal assays of triazines, phenylureas and avermectins. Immunoassays must be properly designed to provide adequate data for pattern recognition. Cross‐reactivity pattern analysis will make multi‐analyte, multi‐antibody immunoassays feasible for many applications in toxicology and hazard assessment. 相似文献
73.
Opsahl Michael S.; Fitz Tony A.; Rexroad Caird E. Jr; Fritz Marc A. 《Human reproduction (Oxford, England)》1996,11(6):1250-1255
We examined the effects of enclomiphene and zuclomiphene, aloneand in combination with oestradiol, on basal and gonadotrophin-stimulatedprogesterone secretion by isolated subpopulations of both large(granulosa-lutein) and small (theca-lutein) ovine luteal cells.Isolated large and small luteal cells derived from intact, enucleatedovine corpora lutea were incubated for 48120 h with orwithout 22R-hydroxycholesterol or pregnenolone (2.5 µM)and a range of enclomiphene, zuclomiphene, and/or oestradiolconcentrations (3100 µM), both with and withoutovine Iuteinizing hormone (100 ng/ml). Spent media were assayedin duplicate for progesterone content by radioimmunoassay. Enclomiphene,zuclomiphene, and oestradiol exhibited equivalent dose-dependentinhibitory effects on basal and gonadotrophin-stimulated smalland large ovine luteal cell progesterone secretion under allsubstrate conditions. Both cell types became more sensitiveto clomiphene inhibition with increasing time in culture. Incombined treatments, the effects of oestradiol and either enclomipheneor zuclomiphene became additive in longer-term cultures andwere never antagonistic In this model system, (i) clomiphene,like oestradiol, appears to inhibit 3-hydroxysteroid dehy-drogenaseactivity, (ii) both stereoisomers act as oestrogen agonists,(iii) neither demonstrates any anti-oestrogenic properties,and (iv) both large and small luteal cells become more sensitiveto clomiphene inhibition with increasing duration of exposure. 相似文献
74.
75.
Petrella T Bagot M Willemze R Beylot-Barry M Vergier B Delaunay M Meijer CJ Courville P Joly P Grange F De Muret A Machet L Dompmartin A Bosq J Durlach A Bernard P Dalac S Dechelotte P D'Incan M Wechsler J Teitell MA 《American journal of clinical pathology》2005,123(5):662-675
Blastic natural killer (NK) cell lymphoma (also termed CD4+CD56+ hematodermic neoplasm) is a recently described entity, with the first case reported in 1994. It was suggested initially that the disease originates from NK cells. Since 1994, single cases and a few small series have been published. In this review, data from the literature and a series of 30 cases from the French and Dutch study groups on cutaneous lymphomas are discussed. The major clinical, histopathologic, and phenotypic aspects of the disease and diagnostic criteria and data suggesting a plasmacytoid dendritic cell origin for the tumor cells are provided. 相似文献
76.
Climacteric symptoms and knowledge about hormone replacement therapy among Hong Kong Chinese women aged 40-60 years 总被引:1,自引:0,他引:1
OBJECTIVES: To evaluate the use of hormone replacement therapy (HRT), the prevalence of climacteric symptoms, and the knowledge about HRT. METHODS: A prospective study was conducted by telephone interview among a randomly selected population-based sample of 978 Hong Kong Chinese women aged 40-60 years. RESULTS: Of 414 women with a history of either natural or surgical menopause, 22 (5.3%) and 17 (4.1%), respectively, were either past or current users of HRT. The climacteric symptom scores of premenopausal women were significantly lower than those of perimenopausal women, but were comparable with those of postmenopausal women. The commonest climacteric symptom was 'muscle and joint pains' which was reported in 553 (56.6%) women, while only 228 (23.3%) and 151 (15.4%) women reported hot flushes and night sweating, respectively. Moreover, only 230 (23.5%) women realized that HRT could relieve menopausal symptoms and only 33 (3.4%) women were aware that HRT was protective against osteoporosis. In general, women with more climacteric symptoms, who had ever used HRT, and those with higher education level and higher family income, had better knowledge about HRT. CONCLUSIONS: Postmenopausal Hong Kong Chinese women have a low HRT usage rate and the majority of them are lacking of the knowledge about HRT. 相似文献
77.
Ultrastructural localization of the 9-kilodalton vitamin D-dependent calcium-binding protein in the murine intraplacental yolk sac 总被引:1,自引:0,他引:1
The calcium-binding protein (CaBP) calbindin has been implicated in the molecular mechanism of placental calcium transfer. Previous light microscopic studies have identified CaBP in visceral (but not parietal) endodermal cells of the yolk sac with the most intense immunocytochemical signal observed in the intraplacental yolk sac. In the present studies, electron microscopy was used to study the localization of CaBP in placenta. Placentas of 17-day pregnant mice were fixed by perfusion in 0.5% glutaraldehyde, embedded in low-temperature Lowicryl K4M, and examined in thin section for specific labeling with a polyclonal antiserum. Antibody to CaBP was localized by using protein A-gold particles which were quantified for subcellular compartmentation by using a Videoplan computer system. A high signal for CaBP was found in the visceral endodermal cells of the intraplacental yolk sac. In these cells, gold particles indicating the location of CaBP were observed over 1) the cytoplasmic matrix where the average number of gold particles per micron 2 was 33; 2) the microvilli (17/micron 2); 3) the mitochondria (17/micron 2); and 4) the nucleus (43/micron 2). Sections from antigen-absorbed controls, by contrast, showed few gold particles: cytosol, 2/micron 2; microvilli, 5/micron 2; mitochondria, 5/micron 2; and nucleus, 4/micron 2. Electron-lucent profiles of the Golgi and endoplasmic reticulum contained no particles in the controls and a low particle count (4/micron 2) in the stained sections. Parietal endodermal cells of the intraplacental yolk sac showed a relatively low signal for CaBP compared with the visceral endodermal cells (5 particles/micron 2 vs. 39).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
78.
BACKGROUND: There has thus far been no empirical research on the occurrence of antenatal psychiatric morbidity in Chinese population. Epidemiological studies in western societies generally show that depressive episodes occur in 10-20% of pregnant women. Longitudinal studies have demonstrated that antenatal depression is one of the most powerful predictors of postnatal depression. There is also a growing literature that shows that antenatal psychological distress can adversely affect maternal and foetal well being. METHODS: At 38 weeks of pregnancy, 238 consecutive women were invited to return for psychiatric assessment. The participants were interviewed using the non-patient version of the Structured Clinical Interview for DSM-IV (SCID-NP). RESULTS: Seventy women (29%) declined to participate, and another 11 (5%) defaulted the SCID interview. Among the 157 women interviewed, the 1-month prevalence of antenatal depression was 4.4%. The 1-month prevalence of all psychiatric diagnoses was 6.4%. The prevalence of antenatal depression and all psychiatric diagnoses for the entire pregnancy was 6.4% and 8.3%, respectively. LIMITATIONS: About a third of eligible subjects did not participate in the study. CONCLUSIONS: A significant proportion of Chinese women suffer from psychiatric morbidity during pregnancy. Depressive disorders are by far the commonest morbidity in the study population. Given the scope of the morbidity and the potential impact on obstetric and neonatal outcomes, early screening and treatment are warranted. 相似文献
79.
Occurrence of leukoplakia and some other oral white lesions among 20 333 adult Swedish people 总被引:1,自引:0,他引:1
Tony Axéll 《Community dentistry and oral epidemiology》1987,15(1):46-51
Among 20,333 people aged 15 yr or above, the prevalences of oral white lesions were calculated based on a partly new classification. The total prevalences were: cheek and lip biting 5.1%, smoker's palate 1.1%, frictional white lesion 5.5%, snuff dipper's lesion 8.0%, preleukoplakia 6.4% and leukoplakia 3.6%. If all these lesions were pooled, the prevalence was 24.8% and if only the entities cheek and lip biting and smoker's palate were excluded it became 20.1%. If weak "preleukoplakic" lesions were excluded from the latter figure the prevalence for marked whitish lesions was 13.8%. Etiologic and clinical subgroups of leukoplakia showed the following prevalences: using the etiologic subgroups, idiopathic leukoplakia 0.7% and tobacco-associated leukoplakia 2.9%; using the clinical subgroups, homogeneous leukoplakia 3.5% and non-homogeneous leukoplakia 0.3%. The intraoral location pattern of leukoplakias was preponderant in the commissural and buccal areas. However, the idiopathic leukoplakias showed a somewhat more even distribution and thus a more similar distribution to that of oral cancer. 相似文献
80.
G Bruns 《Archiv fuer geschwulstforschung》1986,56(4):299-308
In the recent century research in cancer metastasis has greatly improved; nowadays it is a superior topic in cancer literature. Most of its problems result from alternate assumptions: The functional seed and soil and the hemomechanic hypothesis, after all putting two questions on account of metastasis being either a permanent likewise passive or a cascade phenomenon. In regard of metastasizing bronchial-, breast- and prostate carcinomas or multifocal tumors and most of rodent neoplasms a passive tumor cell transport might be a single effect, but the characteristic feature rather a step by step metastasizing cascade, implicating special organ localizations, and the fact, that metastasis distribution correlates with tumor biology, localization of the first metastasis and in manifold metastasizing tumors with typical organ patterns. From introduction of recent in vitro and cloning-techniques the metastasizing potency of tumors now becoming able to be defined by function of its genetic heterogeneity, developing metastasizing phenotypes respective neoplastic evolution by mutation, gene amplification, and epigenetic factors. On the other side having an unique xenobiotic metabolism metastasizing tumor cells are in accordance with the conception of their inherent "commonality". 相似文献