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991.
992.
Ljung T Ahlberg AC Holm G Friberg P Andersson B Eriksson E Björntorp P 《Journal of internal medicine》2001,250(3):219-224
OBJECTIVE: To investigate the effects of a selective serotonin reuptake inhibitor (SSRI) on the neuroendocrine and autonomic nervous system perturbations found in abdominal obesity. DESIGN: Treatment for 6 months with citalopram and for 6 months with placebo using a double-blind, cross-over design, with a 2-month wash-out period between treatment periods. SUBJECTS: Sixteen healthy men, 45-60 years, moderately obese and with an abdominal fat distribution. MEASUREMENTS: Anthropometry, three different depression rating scales, serum lipids, testosterone, IGF-I, oral glucose tolerance test (OGTT), pituitary stimulation with corticotropin releasing hormone (CRH), arithmetic stress test, and excretion of cortisol and metoxycatecholamines in urine, collected during 24 h. RESULTS: Cortisol concentrations in the morning were low before treatment, indicating a perturbed function of the hypothalamic-pituitary-adrenal (HPA) axis. After treatment with citalopram morning cortisol concentrations rose to normal. Cortisol concentrations after stimulation with CRH or stress were elevated by citalopram treatment, but urinary cortisol excretion was unchanged. The glucose concentrations after OGTT (120 min) tended to be reduced, with unchanged insulin concentrations, whilst other metabolic values did not change during treatment. Heart rate after administration of CRH, and during laboratory stress test, decreased by treatment with citalopram. Diurnal urinary excretion of metoxycatecholamines tended to decrease. Neither body mass index nor waist/hip circumference ratio decreased. Depression scores were within normal limits before treatment and did not change. CONCLUSION: The results of this pilot study indicate improvements in the regulation of neuroendocrine-autonomic systems as well as metabolism in abdominal obesity during treatment with an SSRI. 相似文献
993.
Andersson P Olaison G Bodemar G Nyström PO Sjödahl R 《Scandinavian journal of gastroenterology》2002,37(1):68-73
BACKGROUND: This study describes how surgery for Crohn colitis developed between 1970 and 1997, towards the end of which period limited resection and medical maintenance treatment was introduced. METHODS: A cohort of 211 patients with Crohn colitis (115 population-based), of which 84 had a primary colonic resection (42 population-based), was investigated regarding indication for surgery, the time from diagnosis to operation, type of primary colonic resection, risk for permanent stoma and medication over four 7-year periods. RESULTS: Comparison of the periods 1970-90 and 1991-97 revealed that active disease as an indication for surgery decreased from 64% to 25% (P<0.01) while stricture as an indication increased from 9% to 50% (P < 0.001). Median time from diagnosis to operation increased from 3.5 to 11.5 years (P < 0.01). Proctocolectomy or colectomy fell from 68.8% to 10% of the primary resections, whereas segmental resection increased from 31.2% to 90%. At the end of the first 7-year period, 26% had medical maintenance treatment, steroids or azathioprine taken by 7%. Corresponding figures for the last period were 70% and 49%. Patients diagnosed during the last two time-periods had less risk for surgery (P = 0.017), permanent stoma (P < 0.01) and total colectomy (P < 0.01). Findings were similar in the population-based cohort. CONCLUSIONS: Current management of Crohn colitis implies a longer period between diagnosis and surgery, a reduced risk for surgery and permanent stoma, and the replacement of total colectomy by segmental resection. 相似文献
994.
T-cell-dependent B-cell stimulation is H-2 restricted and antigen dependent only at the resting B-cell level. 总被引:31,自引:9,他引:31 下载免费PDF全文
J Andersson M H Schreier F Melchers 《Proceedings of the National Academy of Sciences of the United States of America》1980,77(3):1612-1616
Cloned lines of helper thymus-derived (T) cells produce help for bone marrow-derived (B) cell growth and Ig secretion in the presence of histocompatible adherent cells and of specific antigen. This help stimulates histocompatible as well as histoincompatible B-cell blasts polyclonally. Thus, neither antigen nor histocompatibility, but antigen-unspecific factor(s) for growth and Ig secretion are required to stimulate a B-cell blast through the next round of division. On the other hand, only histocompatible, resting, small B cells, and only those binding their specific antigen, can be stimulated by antigen-activated T-cell help to initiate growth and Ig secretion. The preference of the resting B cells for such collaboration with T-cell help is mapped to the K end of the H-2 histocompatibility locus, and probably constitutes the antigen expressed on B cells by the immune response (I) region. It appears that a resting B cell is excited by the binding of specific antigen to surface Ig and by the interaction of its surface Ia antigen with helper T cells. After this dual recognition the excited B cell can be stimulated by the antigen-unspecific factor(s) generated by the interaction of helper T-cells, adherent cells, and antigen to initiate replication. 相似文献
995.
Blastic transformation of essential thrombocythemia (ET) preceded by chemotherapy is occasionally described in the literature.
In ET as well as in other myeloproliferative disorders the leukemogenic effect of alkylating agents and 32P is well established, and recent reports also indicate a certain leukemogenic effect of hydroxyurea in these disorders. However,
leukemic transformation in untreated ET seems to be a rare event. This is probably due to the fact that, at some time during
their clinical course, most ET patients receive chemotherapy and are thereby exposed to leukemogenic challenge. We report
on a woman with ET who had not received cytoreductive treatment prior to the development of acute myeloid leukemia, indicating
that this transformation was a natural progression of her disorder.
Received: November 26, 1998 / Accepted: June 2, 1999 相似文献
996.
von Willebrand factor antigen and plasminogen activator inhibitor in giant cell arteritis. 下载免费PDF全文
E Nordborg R Andersson L Tengborn S Edén B A Bengtsson 《Annals of the rheumatic diseases》1991,50(5):316-320
Sixty three patients (51 women, 12 men) with giant cell arteritis were studied by serial analyses of von Willebrand factor antigen (vWF: Ag) concentration and plasminogen activator inhibitor activity. Their mean age at the time of diagnosis was 71 years. Two hundred and one randomly selected subjects from the general population, aged 75 years, served as controls. The mean concentration of vWF:Ag in the patients with giant cell arteritis before the start of corticosteroid treatment was 2.63 (SD 1.35) IU/ml compared with 1.71 (0.69) IU/ml in the general population. The vWF:Ag concentration slowly decreased and reached the control range about 18 months after the diagnosis. The vWF:Ag did not correlate with the clinical group of giant cell arteritis nor with the results of temporal artery biopsy. Flare ups and vascular complications were not indicated by the vWF:Ag. Plasminogen activator inhibitor activity in the patients was not significantly different from that of the general population at any time. It was concluded that the determination of vWF:Ag and plasminogen activator inhibitor activity is of limited clinical value in the diagnosis, prognosis, and monitoring of steroid treatment in patients with giant cell arteritis. 相似文献
997.
Teerenhovi L; Knuutila S; Ekblom M; Rossi L; Borgstrom GH; Tallman JK; Andersson L; de la Chapelle A 《Blood》1984,64(5):1116-1122
A major problem in the cytogenetic analysis of hematologic neoplasms has been an inability to identify the cell from which the chromosomes were obtained. We describe a procedure that allows simultaneous analysis of karyotype and cell cytology in mitotic cells. The method differs from conventional cytogenetic analysis in that after mild hypotonic treatment, the cells are cytocentrifuged onto glass slides. In mitotic cells, this procedure often results in adequate spread of the chromosomes within the intact cell membrane. The cytoplasmic structure also remains intact, so that cytologic preparations are of good quality. Morphologic and immunologic identification of mitotic cells can be done using routine hematologic stains, such as Giemsa or Sudan black B, and various antisera using immunofluorescence techniques. The chromosomes can be simultaneously analyzed either without banding on slides stained with Giemsa or with Q-banding on slides stained with immunofluorescence techniques. Identification of numerical and structural karyotype aberrations thus is possible in morphologically identified cells. 相似文献
998.
999.
Inhibitory effects of interleukin 1 on insulin secretion, insulin biosynthesis, and oxidative metabolism of isolated rat pancreatic islets 总被引:12,自引:0,他引:12
Recent observations suggest a role for interleukin 1 (IL-1), a macrophage-derived cytokine, in the autoimmune B cell destruction, which is observed in type 1 diabetes. In the present study we have investigated the effects of IL-1 and two other cytokines, namely tumor necrosis factor (TNF) and interferon-gamma (IFN-gamma) on the pancreatic B cell paying particular attention to insulin production and glucose metabolism. Rat pancreatic islets were isolated and kept in tissue culture for 5 days. The islets were subsequently transferred to media containing medium RPMI 1640 plus 0.5% human serum with or without additions of human recombinant preparations of either IL-1 (25 U/ml), TNF (1000 U/ml), or IFN-gamma (500 U/ml), and cultured for another 48 h. After the culture period the islets were subjected to light microscope examination and different functional tests in short-term incubations in the absence of cytokines. IL-1 was found to reduce insulin release in culture and totally inhibit glucose-stimulated insulin release in short-term incubations. Islet (pro)insulin biosynthesis, glucose oxidation, and oxygen uptake at 16.7 mM glucose were partially inhibited by IL-1. The DNA content of islets cultured with IL-1 was decreased and may partly explain these latter findings. However, inhibition of glucose oxidation could not be seen in islets exposed to IL-1 in short-term experiments only. By light microscopy there were marked signs of degeneration in IL-1 treated islets. TNF and IFN-gamma were essentially without effect on islet morphology or function. The results of this study indicate that IL-1 may be cytotoxic to islet B cells. The primary toxic action of IL-1 seems to involve factors other than an impaired islet glucose metabolism. 相似文献
1000.
B lymphoblastoid cell lines with normal and defective O-glycosylation established from an individual with blood group Tn 总被引:2,自引:0,他引:2
Individuals with the Tn blood group contain terminal serine/threonine- linked N-acetylgalactosamine residues in their blood cells. This is due to lack of UDP-D-galactose: D-N-acetyl galactosamine beta-D-galactosyl transferase from part of their red cells and probably from their leukocytes. We have established B lymphoblastoid cell lines from such an individual by in vitro infection of his lymphocytes with Epstein- Barr virus. The original line contained a mixture of cells reactive and nonreactive with Helix pomatia lectin (Hp). These cells were subcloned after staining with fluorescent Hp by a fluorescence-activated cell sorter (FACS) into homogeneous, phenotypically stable lines of Hp- positive (Hp+) and Hp-negative (Hp-) cells. The molecular differences between the membrane glycoproteins were characterized by carbohydrate- specific surface labeling techniques, Hp affinity chromatography, polyacrylamide slab gel electrophoresis and glycopeptide/oligosaccharide analysis. The major O-glycosidic membrane glycoprotein (GP105) was retained on Hp-Sepharose columns only from Hp+ cells, whereas the common leukocyte antigen (GP160-200) was partially retained on Hp columns from both lines. These proteins were isolated by immune precipitation with monoclonal antibodies and characterized. The results show that the GP105 glycoprotein from Hp+ cells contains terminal N-acetylgalactosamine residues but also more complex oligosaccharides. The common leukocyte antigen showed different electrophoretic mobilities in Hp+ and Hp- cells. UDP-galactose D-N- acetyl galactosamine beta-galactosyl transferase was almost absent in the Hp+ cells. These cell lines are useful for studies on the functional role and regulation of the biosynthesis of O-glycosidic carbohydrates. 相似文献