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排序方式: 共有1547条查询结果,搜索用时 31 毫秒
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Y Xu D Zagoura C Keck D Pietrowski 《Experimental and clinical endocrinology & diabetes》2006,114(10):590-595
Corpus luteum development is regulated by gonadotropins and accompanied by extremely rapid vascularization of the avascular granulosa cell compartiment by endothelial cells (EC). The proliferation of Granulosa cells (GC) and EC is a complex interplay and takes place in a spatially and temporarily coordinated manner. The erythropoietin-producing hepatoma amplified sequence (Eph) receptors and their ligands-the ephrins- are a recently detected family of membrane located protein tyrosine kinases which play a crucial role in the growth and development of nerve and blood vessel network. We report about the mRNA expression pattern of Ephs and their ligands in human GC, in human EC, and in carcinoma cell lines OvCar-3 and Hela. The mRNA of EphA4, EphA7, ephrinA4, ephrinB1 and ephrinB2 was detected in GC and EC, while EphA2 was expressed only in GC. The expression of various Ephs and ephrins did not change in GC after stimulation with human chorion gonadotropin. Our study analyzes for the first time the expression of the complete human Eph/ephriny-system in GC and in EC. The remarkable similarity between these two cell types supports the theory of a functional relationship of EC and GC. In addition, it was shown that hCG is not a major determinant of Eph/ephrin regulation in GC. 相似文献
3.
Kowalczyk JR Gaworczyk A Winnicka D Lejman M Babicz M 《Cancer Genetics and Cytogenetics》2003,142(1):51-55
Fluorescence in situ hybridization (FISH) using chromosome-specific DNA probes is rapidly becoming a part of clinical laboratory practice. However, as a relatively new clinical test, it is not yet standardized and for practical reasons each laboratory must establish its own criteria. For this purpose we have evaluated the specificity of a dual-color BCR/ABL translocation probe by establishing the range of BCR/ABL fusion-positive scores in a healthy donor group. The false positive rate (FPR), determined by the percent of FISH BCR/ABL fusion-positive cells found in the specimens of healthy donors, was estimated at 2.3% (mean = 1%-4%). Thus the cut-off value for false positive nuclei was set at 5%. 相似文献
4.
Thyroid-stimulating hormone and thyroid-stimulating hormone receptor structure-function relationships 总被引:9,自引:0,他引:9
This review focuses on recent advances in the structure-function relationships of thyroid-stimulating hormone (TSH) and its receptor. TSH is a member of the glycoprotein hormone family constituting a subset of the cystine-knot growth factor superfamily. TSH is produced by the pituitary thyrotrophs and released to the circulation in a pulsatile manner. It stimulates thyroid functions using specific membrane TSH receptor (TSHR) that belongs to the superfamily of G protein-coupled receptors (GPCRs). New insights into the structure-function relationships of TSH permitted better understanding of the role of specific protein and carbohydrate domains in the synthesis, bioactivity, and clearance of this hormone. Recent progress in studies on TSHR as well as studies on the other GPCRs provided new clues regarding the molecular mechanisms of receptor activation. Such advances are a result of extensive site-directed mutagenesis, peptide and antibody approaches, detailed sequence analyses, and molecular modeling as well as studies on naturally occurring gain- and loss-of-function mutations. This review integrates expanding information on TSH and TSHR structure-function relationships and summarizes current concepts on ligand-dependent and -independent TSHR activation. Special emphasis has been placed on TSH domains involved in receptor recognition, constitutive activity of TSHR, new insights into the evolution of TSH bioactivity, and the development of high-affinity TSH analogs. Such structural, physiological, pathophysiological, evolutionary, and therapeutic implications of TSH-TSHR structure-function studies are frequently discussed in relation to concomitant progress made in studies on gonadotropins and their receptors. 相似文献
5.
Sowiska-Klencka D Klencki M Dedecjus M Lewiski A Pawlikowski M 《Endocrine pathology》2000,11(2):173-178
Nucleolar organizer regions (NORs) are segments of DNA, encoding for ribosomal RNA. They are associated with argyrophilic
proteins and, thus, they can be localized through silver staining. A correlation has been shown between the number, the size,
or the intranuclear localization of AgNORs, and the proliferative activity of cells. The aim of this study was to examine
numerous features of AgNORs in pituitary adenomas and to relate them to immunohistochemical typing of tumor. Histologic slides
from 32 pituitary tumors and one normal pituitary were silver-stained and analyzed with a computerized system for microscopic
image analysis, supported by an AgNORmeter95 program. All the tumors were also immunocyto chemically characterized. We have
found that gonadotropinomas, when compared with plurihormonal adenomas, revealed a lower proportion of nuclei with a single
AgNOR and a higher percentage of marginal dots. Recurrent adenomas, when compared with primary adenomas, showed a higher proportion
of nuclei with three AgNOR dots, a larger total area of dots in the nuclei, and a higher standard deviation of the AgNOR dot
area in the nucleus. Adenomas immunopositive for prolactin, when compared with immunonegative ones, showed a larger mean area
of the AgNOR dot, a larger area of the biggest dot in the nucleus, and a higher proportion of nuclei within a single dot.
These results suggest that the estimated parameters of AgNOR dots differ according to tumor aggressiveness and to the hormone
immunopositivity of pituitary adenomas. 相似文献
6.
Mariusz Papp Piotr Gruca Pierre-Alain Boyer Elisabeth Moca?r 《Neuropsychopharmacology》2003,28(4):694-703
Chronic mild stress (CMS), a well-validated model of depression, was used to study the effects of the melatonin agonist and selective 5-HT(2C) antagonist agomelatine (S 20098) in comparison with melatonin, imipramine, and fluoxetine. All drugs were administered either 2 h before (evening treatment) or 2 h after (morning treatment) the dark phase of the 12-h light/dark cycle. Chronic (5 weeks) evening treatment with agomelatine or melatonin (both at 10 and 50 mg/kg i.p.) dose-dependently reversed the CMS-induced reduction in sucrose consumption. The magnitude and time course of the action of both drugs was comparable to that of imipramine and fluoxetine (both at 10 mg/kg i.p.); however, melatonin was less active than agomelatine at this dose. The effect of evening administration of agomelatine and melatonin was completely inhibited by an acute injection of the MT(1)/MT(2) antagonist, S 22153 (20 mg/kg i.p.), while the antagonist had no effect in animals receiving fluoxetine or imipramine. When the drugs were administered in the morning, agomelatine caused effects similar to those observed after evening treatment (with onset of action faster than imipramine) but melatonin was ineffective. Moreover, melatonin antagonist, S 22153, did not modify the intakes in stressed animals receiving morning administration of agomelatine and in any other control and stressed groups tested in this study. These data demonstrate antidepressant-like activity of agomelatine in the rat CMS model of depression, which was independent of the time of drug administration. The efficacy of agomelatine is comparable to that of imipramine and fluoxetine, but greater than that of melatonin, which had no antidepressant-like activity after morning administration. While the evening efficacy of agomelatine can be related to its melatonin receptors agonistic properties, its morning activity, which was not inhibited by a melatonin antagonist, indicates that these receptors are certainly required, but not sufficient to sustain the agomelatine efficacy. It is therefore suggested that the antidepressant-like activity of agomelatine depends on some combination of its melatonin agonist and 5-HT(2C) antagonist properties. 相似文献
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Mariusz Holtzer Rafa Dako Sylwester Piasny Micha Kubecki Dariusz Droyski Agnieszka Roczniak Mateusz Skrzyski Angelika Kmita 《Materials》2021,14(10)
The assessment of the harmfulness of moulding and core sands is mainly based on investigations of compositions of gases emitted by liquid casting alloys during the mould pouring. The results of investigations of moulding sands obtained under industrial conditions are presented in this paper. A unique research stand was designed and built for this aim. It allowed us to determine emissions of gases at individual stages of casting a mass up to 50 kg. This approach enables simulation of foundry conditions. Moulding sands bound by organic binders (phenol-formaldehyde; furan), inorganic binders and green sand, were subjected to investigations. The composition of gases that evolved during the individual stages, pouring, cooling and knocking out, was tested each time, and the contents of Polycyclic Aromatic Hydrocarbons (PAHs) and benzene, toluene, ethylbenzene, and xylenes (BETX) were analysed. Investigations indicated that the emission of gases from sands with inorganic binders is negligible when compared with the emission of gases from sands with organic binders. The emission of gases from green sand is placed in the middle of the scale. As an example: the sand with furan resin emitted 84 mg of BTEX (in recalculation for 1 kg of sand) while from sands with inorganic binders there was a maximum of 2.2 mg (for 1 kg of sand). In the case of sands with inorganic binders, MI and MC sands indicated comparable and very low emissions of gases from the PAHs group, at the level of 0.018 mg and 0.019 mg for 1 kg of sand, respectively. The higher emission of PAHs from MG sand is the result of its different way of hardening (a binder was of an organic character) than of sands MI and MC. 相似文献
10.
Piotr Remiszewski Ewa Szczerba Piotr Kalinowski Beata Gierej Krzysztof Dudek Mariusz Grodzicki Marcin Kotulski Rafa? Paluszkiewicz Waldemar Patkowski Krzysztof Zieniewicz Marek Krawczyk 《World journal of gastroenterology : WJG》2014,20(32):11333-11339
AIM: To investigate the indications and outcomes of liver transplantation for hepatic epithelioid hemangioendothelioma (HEHE).METHODS: Between 1989 and August 2013, in the Department of General, Transplant, and Liver Surgery, Medical University of Warsaw, 1306 orthotopic liver transplantations (OLTx) were performed, including 72 retransplantations. Unresectable HEHE was an indication for OLTx in 10 patients (0.8% of primary OLTx), the mean age of the patients was 40.5 ± 13.3 years (range 23-65 years), and the male-to-female ratio was 2:8. Kaplan-Meier survival analysis in HEHE, hepatocellular carcinoma (HCC), and other OLTx recipients groups was performed. The differences in mortality were compared using the χ2 test. A P-value < 0.05 indicated statistical significance.RESULTS: No concomitant liver disease was found in any patient. There was no neoadjuvant chemotherapy or radiotherapy. Liver function test results were normal in most of the patients. The levels of alpha-fetoprotein, carcinoembryonic antigen, and carbohydrate antigen 19-9 were normal. In immunohistochemical staining, the neoplastic cells were positive for factor VIII-related antigen, CD31, and CD34, which are endothelial cell markers, and negative for cytokeratin 19, cytokeratin 7, and HepPar-1. Nine patients were alive without tumor recurrence. One patient died 2 mo after OLTx due to septic complications. No morbidity was observed. Maximum follow-up was 11.4 years, with a minimum of 1 mo. The cumulative survival rate at the end of follow-up in HEHE patients was 87.5% compared with 54.3% in the HCC group and 76.3% in the other OLTx recipients group (χ2 test = 1.784, df = 2, P = 0.409).CONCLUSION: Unresectable HEHE, without extrahepatic metastases is an excellent indication for liver transplantation. Long-term survival is very good and much better than in HCC patients and the entire group of OLTx patients. 相似文献