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61.
Günther Vogel Ingrid Stoeckert Edna Meyering 《Pflügers Archiv : European journal of physiology》1971,325(3):247-261
Zusammenfassung Die Schleimhaut des Duodenums beim Kaninchen sezerniert eine blutisotone Flüssigkeit, deren Hauptcharakteristikum ihr HCO3
–-Gehalt von fast 100 mMol/l ist. Auf die Instillation einer Lösung, die wie das duodenale Sekret zusammengesetzt ist, reagiert das Jejunum mit einer isotonen Absorption bei nur geringfügigen Konzentrationsänderungen der Konstituenten der Instillationslösung. Das Ileum reagiert analog dem Jejunum, nur sind die Absorptionsraten für Flüssigkeit und die geprüften Solute größer als im Jejunum. Im Colon kommt es zu einer Enterosorption von Flüssigkeit mit teilweise beträchtlichen Konzentrationserniedrigungen der in der Installationslösung enthaltenen Solute.Auf die Instillation einer blutisotonen NaCl-Lösung reagiert das Jejunum stets mit einer Absorption von Flüssigkeit. Na+ und Cl– werden absorbiert, während HCO3
–, K+ und Harnstoff netto sezerniert werden. Im Colon kommt es unter den Bedingungen des 30 min-Versuches zur enterosorption von Flüssigkeit, zur Absorption von osmotisch aktivem Material, Na+ und Cl–, während HCO3
–, K+ und Harnstoff sezerniert werden.Auf die Instillation reinen Wassers reagiert das Jejunum mit einer Absorption von Flüssigkeit sowie einer Enterosorption aller geprüften Solute in das Jejunum hinein, daß fast Konzentrationsgleichheit mit dem Plasma eingestellt wird. Im Colon kommt es im 30 min-Versuch teils zur Enterosorption, teils zur Absorption von Flüssigkeit. Nach 60 min wird in allen Fällen eine Absorption von Flüssigkeit beobachtet. Die Gleichgewichtskonzentrationen im Jejunum sind: Osmolarität 296,0 mOsmol/l, Na+ 78,6 mMol/l, Cl– 24,6 mMol/l, HCO3
– 54,8 mMol/l, K+ 2,2 mMol/l, Harnstoff 59,9 mg/100 ml. Die analogen Werte für das Colon lauten: Osmolarität 184,0 mOsmol/l, Na+ 11,6 mMol/l, Cl– 12,9 mMol/l, HCO3
– 25,9 mMol/l, K+ 16,4 mMol/l, Harnstoff 18,8 mg/100 ml. 相似文献
62.
Hüffmeier U Hausser I Reis A Rauch A 《American journal of medical genetics. Part A》2005,135(2):195-199
We present a family of Iraqui origin with three siblings affected by a novel type of progressive hyperpigmentation syndrome. The generalized initially diffuse, later disseminated hyperpigmentation started in early infancy and increased during childhood. It also affected palms and soles, and the face but spared the cheeks. Additional features were dry, itchy and sunlight sensitive skin, dystrophy of toe nails, hair loss, and myopia, but normal sweat glands. Light and electron microscopy showed signs of pigment incontinence and compound melanosomes as well as fibrillar bodies. The occurrence of this entity in affected siblings from a consanguineous mating suggests autosomal recessive inheritance. Extensive review of the literature showed no previous report with this distinct combination of clinical and microscopic findings. 相似文献
63.
Johannsson OT Staff S Vallon-Christersson J Kytöla S Gudjonsson T Rennstam K Hedenfalk IA Adeyinka A Kjellén E Wennerberg J Baldetorp B Petersen OW Olsson H Oredsson S Isola J Borg A 《Laboratory investigation; a journal of technical methods and pathology》2003,83(3):387-396
A human tumor xenograft (L56Br-X1) was established from a breast cancer axillary lymph node metastasis of a 53-year-old woman with a BRCA1 germ-line nonsense mutation (1806C>T; Q563X), and a cell line (L56Br-C1) was subsequently derived from the xenograft. The xenograft carries only the mutant BRCA1 allele and expresses mutant BRCA1 mRNA but no BRCA1 protein as determined by immunoprecipitation or Western blotting. The primary tumor, lymph node metastasis, and xenograft were hypodiploid by DNA flow cytometry, whereas the cell line displayed an aneuploidy apparently developed via polyploidization. Cytogenetic analysis, spectral karyotyping, and comparative genomic hybridization of the cell line revealed a highly complex karyotype with numerous unbalanced translocations. The xenograft and cell line had retained a somatic TP53 missense mutation (S215I) originating from the primary tumors, as well as a lack of immunohistochemically detectable expression of steroid hormone receptors, epidermal growth factor receptor, human epidermal growth factor receptor 2 (HER-2), and keratin 8. Global gene expression analysis by cDNA microarrays supported a correlation between the expression profiles of the primary tumor, lymph node metastasis, xenograft, and cell line. We conclude that L56Br-X1 and L56Br-C1 are useful model systems for studies of the pathogenesis and new therapeutic modalities of BRCA1-induced human breast cancer. 相似文献
64.
65.
IFN-gamma-enhanced allergen penetration across respiratory epithelium augments allergic inflammation 总被引:2,自引:0,他引:2
Reisinger J Triendl A Küchler E Bohle B Krauth MT Rauter I Valent P Koenig F Valenta R Niederberger V 《The Journal of allergy and clinical immunology》2005,115(5):973-981
BACKGROUND: Respiratory allergen contact is the critical event in the elicitation and boosting of allergen-specific immune responses, as well as in the induction of immediate and late inflammatory reactions. OBJECTIVE: We sought to investigate the influence of various factors of allergic inflammation on the integrity and barrier function of respiratory epithelium for allergens. METHODS: We cultured the human bronchial epithelial cell line 16HBE14o- in a transwell culture system as a surrogate of intact respiratory epithelium and used purified iodine 125-labeled recombinant major birch pollen allergen (rBet v 1) to study the extent, kinetics, and factors influencing transepithelial allergen penetration. RESULTS: Culture supernatants from activated allergen-specific T H 1 clones decreased transepithelial resistance. A screening of various factors (histamine, IFN-gamma, IL-1beta, IL-2, IL-3, IL-4, IL-5, IL-8, IL-12, and TNF-alpha) identified IFN-gamma as a potent factor capable of reducing epithelial barrier properties and enhancing transepithelial allergen penetration. Increased submucosal allergen concentrations caused by IFN-gamma-mediated reduction of epithelial barrier function provoked a more than 7-fold augmentation of histamine release from sensitized basophils. CONCLUSION: These results demonstrate that the T H 1 cell-derived cytokine IFN-gamma facilitates allergen penetration through the respiratory epithelium and thereby can aggravate allergic inflammation. 相似文献
66.
Nikos Pandis Sverre Heim Georgia Bardi Ingrid Idvall Nils Mandahl Felix Mitelman 《Genes, chromosomes & cancer》1993,6(1):51-57
Short-term cultures from 20 breast carcinomas were analyzed cytogenetically. A normal female chromosome complement was found in 4 cases. Clonal chromosome aberrations were detected in 16 tumors. In 10 tumors, multiple cytogenetic clones were found; in 2 cancers the clones were related, reflecting clonal evolution, but in the remaining 8 tumors the clones were cytogenetically unrelated, indicating clonal heterogeneity in the origin of the tumor parenchyma. Correlation analysis between karyotypic and pathologic parameters indicated that cases with complex karyotypes and/or cytogenetically unrelated clones, when compared with cases with a single simple karyotypic abnormality, were generally of higher histologic malignancy grade, had more mitoses in the histologic sections, and also more often had carcinoma in situ lesions in the same breast. © 1993 Wiley-Liss, Inc. 相似文献
67.
Connective tissue growth factor expression and Smad signaling during mouse heart development and myocardial infarction. 总被引:5,自引:0,他引:5
Susana M Chuva de Sousa Lopes Alie Feijen Jeroen Korving Olexander Korchynskyi Jonas Larsson Stefan Karlsson Peter ten Dijke Karen M Lyons Roel Goldschmeding Pieter Doevendans Christine L Mummery 《Developmental dynamics》2004,231(3):542-550
Connective tissue growth factor (CTGF) is reported to be a target gene of transforming growth factor beta (TGFbeta) and bone morphogenetic protein (BMP) in vitro. Its physiological role in angiogenesis and skeletogenesis during mouse development has been described recently. Here, we have mapped expression of CTGF mRNA during mouse heart development, postnatal adult life, and after experimental myocardial infarction. Furthermore, we investigated the relationship between CTGF and the BMP/TGFbeta signaling pathway in particular during heart development in mutant mice. Postnatally, CTGF expression in the heart became restricted to the atrium. Strikingly, 1 week after myocardial infarction, when myocytes have disappeared from the infarct zone, CTGF and TGFbeta expression as well as activated forms of TGFbeta but not BMP, Smad effector proteins are colocalized exclusively in the fibroblasts of the scar tissue, suggesting possible cooperation between CTGF and TGFbeta during the pathological fibrotic response. 相似文献
68.
69.
70.
Immune Responses to Bile-Tolerant Helicobacter Species in Patients with Chronic Liver Diseases, a Randomized Population Group, and Healthy Blood Donors 下载免费PDF全文
Olga Ananieva Ingrid Nilsson Tamara Vorobjova Raivo Uibo Torkel Wadstrm 《Clinical and Vaccine Immunology : CVI》2002,9(6):1160-1164
Bile-tolerant Helicobacter species such as Helicobacter pullorum, Helicobacter bilis, and Helicobacter hepaticus are associated with hepatic disorders in animals and may be involved in the pathogenesis of chronic liver diseases (CLD) in humans. Antibody responses to cell surface proteins of H. pullorum, H. bilis, and H. hepaticus in serum samples from patients with CLD, a randomized population group, and healthy blood donors were evaluated by using enzyme linked immunosorbent assay (ELISA). The results were compared with the antibody responses to Helicobacter pylori. For analysis of a possible cross-reactivity between bile-tolerant Helicobacter species and H. pylori, sera from a subpopulation of each group were absorbed with a whole-cell extract of H. pylori and retested by ELISA. Results before absorption showed that the mean value of the ELISA units for H. pullorum was significantly higher in patients with CLD than in healthy blood donors (P = 0.01). Antibody reactivity to cell surface protein of H. hepaticus was also significantly higher in the CLD patients than in the healthy blood donors and the population group (P = 0.005 and P = 0.002, respectively). Following the absorption, antibody responses to H. pullorum decreased significantly in all three groups (P = 0.0001 for CLD patients, P = 0.0005 for the population group, and P < 0.0001 for the blood donors), indicating that cross-reactivity between H. pylori and other Helicobacter spp. occurs. The antibody responses to H. hepaticus and H. bilis in CLD patients remained high following absorption experiments compared to ELISA results before absorption. The significance of this finding requires further investigations. 相似文献