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排序方式: 共有8097条查询结果,搜索用时 31 毫秒
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Judith Brock Andreas Schmid Thomas Karrasch Petra Pfefferle Jutta Schlegel Inga Busse Annette Hauenschild Barbara Schmidt Maria Koukou Efthymia Arapogianni Andreas Schultz Miriam Thomalla Secil Akinci Johannes Kruse Winfried Padberg Andreas Schffler Jens Albrecht 《Clinical endocrinology》2019,91(3):400-410
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Riemer H J A Slart Ali Agool Dirk J van Veldhuisen Rudi A Dierckx Jeroen J Bax 《Journal of nuclear medicine》2006,47(8):1307-1311
SPECT with 99mTc-labeled agents is better able to detect viability after nitrate administration. Nitrates induce vasodilation and may increase blood flow to severely hypoperfused but viable myocardium, thereby enhancing tracer delivery and improving the detection of viability. Quantitative data on the changes in blood flow are lacking in SPECT but can be provided by PET. The aim of the present study was to use PET to evaluate whether nitrate administration increases blood flow to chronically dysfunctional but viable myocardium. METHODS: 13N-Ammonia PET was used to quantitatively assess blood flow, and 18F-FDG PET was used as the gold standard to detect viable myocardium. Twenty-five patients with chronic ischemic left ventricular dysfunction underwent 13N-ammonia PET at rest and after nitrate administration. RESULTS: A significant increase in nitrate-enhanced blood flow was observed in viable segments (from 0.55 +/- 0.15 to 0.68 +/- 0.24 mL/min/g, P < 0.05). No statistically significant change in blood flow was observed in nonviable segments (0.60 +/- 0.20 vs. 0.55 +/- 0.18 mL/min/g). A ratio of at least 1.1 for nitrate-enhanced flow to resting flow allowed optimal detection of viable myocardium, yielding a sensitivity of 82% with a specificity of 100%. CONCLUSION: 13N-Ammonia PET showed a significant increase in nitrate-enhanced blood flow in viable myocardium, whereas blood flow remained unchanged after nitrate administration in nonviable myocardium. Nitrate use during myocardial perfusion imaging will lead to improved assessment of myocardial viability. 相似文献
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Synergistic effect of low dose Cyclosporine A and human interleukin 10 overexpression on acute rejection in rat lung allotransplantation 总被引:3,自引:0,他引:3
Jaroslaw Pierog Amiq Gazdhar Uz Stammberger Matthias Gugger Steven Hyde Iacob Mathiesen Tomasz Grodzki Ralph A. Schmid 《European journal of cardio-thoracic surgery》2005,27(6):1030-1035
Objective: Electroporation mediated transfer of plasmid DNA into peripheral muscle results in high transfection efficiency. The aim of this study was to investigate the effect of gene transfer of human IL-10 (hIL-10) into the tibialis anterior muscle (MTA) in combination with low dose Cyclosporine A (CsA) on acute rejection of lung allografts in the rat. Methods: Lung allotransplantation was performed from male BN donor to male Fisher F344 rats. Gene transfer was achieved by intramuscular injection into the MTA of the recipient followed by electroporation (4×20 ms impulses at 200 V/cm) 24 h prior to the transplantation. Group A (n=5) received CsA (2.5 mg/kg bw ip) for 5 days post-transplant and group B (n=5) 2.5 μg of PCIK hIL-10 (plasmid expression vector containing human CMV immediate early gene promoter and enhancer) and a low dose CsA (2.5 mg/kg bw i.p.). Graft function was assessed by blood gas at day 5 after exclusion of the native lung. Animals were sacrificed and blood was drawn to measure serum hIL-10 levels (ELISA) and tissue was sampled for histological grading of rejection. Results: Local expression of hIL-10 was confirmed at the mRNA level by in situ hybridization. All group A control animals showed severe signs of rejection. At day 5 all grafts in group B showed good gas exchange mean PaO2 233±123 mmHg, vs 44±8 mmHg in group A. Histological examination revealed moderate to severe rejection in all animals in group A (IIIB, ISHLT) in contrast to low moderate rejection in group B (II–IIIA). hIL-10 serum levels on day 5 were 14±7 pg/ml in group B vs. 0 in group A. Conclusions: Electroporation mediated hIL-10 overexpression in a peripheral muscle of the recipient in combination with low dose CsA reduces acute rejection in this model of rat lung allotransplantation. 相似文献
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G Oberhuber T Schmid R Erdk?nig W Thaler D Ofner G K?r?szi G Klima R Margreiter 《European surgical research. Europ?ische chirurgische Forschung. Recherches chirurgicales européennes》1991,23(3-4):206-213
The effect of ciclosporin (CS) and methotrexate (MTX) on the development of graft-versus-host (GvH) disease was examined after small bowel allotransplantation in the rat. The drugs were tested either alone or in combination. Lewis small bowel allografts were transplantated into Brown Norway recipients in a heterotopic position. The native small bowel, spleen, liver, skin, mesenteric lymph nodes and the kidney of the recipients were examined histologically 5, 10 and 20 days after allotransplantation. Intraepithelial lymphocyte numbers were determined quantitatively in the native small bowel. The relative spleen weight of the host was determined after sacrifice for estimation of the severity of GvH disease. Grade I GvH reaction of the native small bowel occurred in the animals without immunosuppression, but graft rejection predominated in this group. Treatment with CS was effective in the early postoperative periods; after 10 and 20 days GvH lesions in the native small bowel were comparable to those observed in the allogeneic combinations. MTX had a detrimental effect on the allografts and the GvH reaction was augmented. When CS and MTX were combined, GvH lesions were comparable to those in the animals treated solely with CS. Animals, however, suffered from heavy side effects. The spleen, liver, lymph nodes and kidney exhibited only unspecific histologic changes, which could not unequivocally be recognized as a GvH reaction. This was true for all groups. As a conclusion it can be said that GvH reaction occurs in the early postoperative period in a fully allogeneic model and cannot be prevented by CS in the dosae used. MTX was not seen to be of any value in this regard. 相似文献
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PLASMA FOLLISTATIN CONCENTRATIONS INCREASE FOLLOWING LIPOPOLYSACCHARIDE ADMINISTRATION IN SHEEP 总被引:1,自引:0,他引:1
Rudi Klein Iain J. Clarke† Mark P. Hedger† David M. Robertson† 《Clinical and experimental pharmacology & physiology》1996,23(8):754-755
1. The effect of inflammation induced by lipopolysaccharide (LPS) injection on plasma follistatin (FS) concentrations was investigated. 2. Plasma FS and tumour necrosis factor-α concentrations increase following LPS administration in ewes. 3. The rise in FS is similar, but more sustained, to that previously observed after surgery. 4. These results indicate a possible functional link between FS, inflammation and the acute-phase response. 相似文献
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A H Schmid 《Psychiatry》1991,54(4):358-367
Many of the terms used to describe conditions in elderly individuals, whether medical (deterioration, involution, degeneration) or neurobehavioral (impairment, dysfunction), imply deficiency. The complex of distorted views of real impairment, illness, or disability may be described as the deficiency model. Although developmental theory has expanded explosively and could offer an alternative frame of reference to dispel denigration of the elderly condition, late life continues to be viewed as lacking all redeeming aspects, while mortality is considered an obstacle to prolonging life rather than one of its determinants. Deficiency-model thinking has influenced the conduct of epidemiologic, neurobiologic and clinical research, whose results in turn have often been interpreted to reinforce such thinking. It can also distort clinical approaches to diagnosis and treatment of late-life disorders. This paper offers instead an alternative approach that focuses on late life as a developmental task. 相似文献