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排序方式: 共有2899条查询结果,搜索用时 9 毫秒
1.
Gil Bolotin Frederik H. van der Veen Roberto Lorusso Tamir Wolf Robert Sachner Rona Shofti Jan J. Shreuder Gideon Uretzky 《European journal of cardio-thoracic surgery》2002,21(6):975-980
Objective: Descending and ascending aortomyoplasty are two surgical procedures intended to induce hemodynamic benefits similar to those of the intra-aortic-balloon-pump (IABP). To date, there have been no studies comparing the two surgical techniques. The objective of this study was to compare coronary blood flow augmentation and afterload reduction as produced by descending and ascending aortomyoplasty counterpulsation Methods: Twenty-two mongrel dogs (18–35 kg) underwent IABP application (n=7), descending (n=8), or ascending (n=7) aortomyoplasty. Left anterior descending (LAD) coronary artery blood flow was measured using a Transonic Doppler flow probe. Left ventricular pressure as well as aortic pressures proximal and distal to either the aortomyoplasty site or the IABP position were monitored continuously. Results: Descending aortomyoplasty induced higher elevation in the LAD blood flow during assisted beats (27% from 10.8±4 to 13.8±6 ml/min, P<0.001) than that induced by either ascending aortomyoplasty (19% from 11.7±5 to 14±5 ml/min, P<0.001) or IABP counterpulsation (18% from 8.6±3 to 10.2±4 ml/min, P<0.001). Conversely, while ascending aortomyoplasty reduced the left ventricular end-diastolic pressure by 16% (from 60±18 to 50±22 mmHg, P<0.001), similar to the 16% after load reduction achieved by the IABP counterpulsation, descending aortomyoplasty failed to induce afterload reduction. Conclusions: Descending aortomyoplasty produces higher coronary blood flow augmentation than either ascending aortomyoplasty or IABP. However, afterload reduction comparable to that achieved by IABP was observed only with ascending aortomyoplasty and not with descending aortomyoplasty. 相似文献
2.
Uta Kraus-Tiefenbacher Lelia Bauer Antonella Scheda Carola Schoeber Joerg Schaefer Volker Steil Frederik Wenz 《BMC cancer》2007,7(1):178
Background
For patients suffering of recurrent breast cancer within the irradiated breast, generally mastectomy is recommended. The normal tissue tolerance does not permit a second full-dose course of radiotherapy to the entire breast after a second breast-conserving surgery (BCS). A novel option is to treat these patients with partial breast irradiation (PBI). This approach is based on the hypothesis that re-irradiation of a limited volume will be effective and result in an acceptable frequency of side effects. The following report presents a single center experience with intraoperative radiotherapy (IORT) during excision of recurrent breast cancer in the previously irradiated breast. 相似文献3.
4.
5.
Dermatitis in bulb growers 总被引:2,自引:0,他引:2
Derk P. Bruynzeel Edith M. de Boer Elly J. Brouwer Frederik A. de Wolff Peter de Haan 《Contact dermatitis》1993,29(1):11-15
A damaged skin forms a health hazard in flower-bulb growers as it enables higher permeation rates For pesticides than normal skin. Therefore, an investigation was performed into the skin condition of 103 bulb growers and 49 controls. Contact dermatitis of the hands was of the same order (11 and 10%) in both groups. However, minor signs of dermatitis were seen more often in bulb growers (30 versus 8%, p <0.05). Most growers had contact with narcissus sap during the investigation. This irritant sap, as well as many other skin contacts with irritants such as hyacinth dust and pesticides, seemed to be responsible for many skin complaints. Contact serialization was suspected in 19 growers and 3 controls. Patch tests showed that contact sensitization existed to pesticides in probably 10, and to flower-bulb extracts in 4 growers. Reactions to propachlor were not regarded as very reliable as the test concentration seemed to be marginally irritant. There were only a few allergic reactions to narcissus (3) and tulip (2) and none to hyacinth. This investigation showed that minor irritant contact dermatitis was frequent in bulb growers, and indicated that contact sensitization to pesticides and bulbs seemed to be a less frequent but important cause of dermatitis. 相似文献
6.
A comparison was made of the contractions, induced by LTD4, histamine and phospholipase A2 in parenchymal strips of guinea pig (GPLP), porcine and human lung in a cascade superfusion system. The effects of LTD4 and phospholipase A2 on the release of TxA2 in these tissues and of TxA2, 5-HT and acetylcholine on the GPLP were also determined.In the GPLP strip, the LTC4-induced contractions are due for±80% to the release of TxA2 and for±20% to the direct effect of LTC4.The guinea pig tissue displayed the highest sentivity towards all substances, except to the contraction induced by histamine, which was most effective in the porcine tissue. Low activities wer found in the human tissue in all tests. The reason for these effects may be a difference in activities or number of cell types which participate in the reactions leading to the contractions. 相似文献
7.
C. H. Kirkpatrick R. R. Rich R. G. Graw T. K. Smith Irad Mickenberg G. N. Rogentine 《Clinical and experimental immunology》1971,9(6):733-748
The immunological defect in a patient with chronic mucocutaneous moniliasis was characterized. While his Candida skin test was negative. exposure of his lymphocytes to candida extracts in vitro produced an increase in thymidine incorporation. Supernatants from cultures of antigen-stimulated lymphocytes did not contain macrophage migration-inhibition factor (MIF) activity.
Restoration of the immune system with transfusions of immuno-competent allogeneic lymphocytes was accompanied by conversion of the Candida skin test to positive, and MIF production by his lymphocytes. During the period that his immune system remained intact, there was marked clearing of the moniliasis. Eight months following the transfusions, the moniliasis recurred and when restudied, the patient again had negative skin tests and insignificant MIF production.
These observations demonstrate the importance of mediators in the expression of delayed hypersensitivity and provide evidence of a role of cellular immunity in resistance to certain chronic fungal infections.
相似文献8.
9.
Graft-versus-host disease. Morphologic variation and differential diagnosis in 8 cases of HL-A matched bone marrow transplantation. 总被引:1,自引:5,他引:1 下载免费PDF全文
10.
David Laurin Eric Spierings Lars T van der Veken Abdelbasset Hamrouni J H Frederik Falkenburg Gerard Souillet Corine Vermeulen Annie Farre Claire Galambrun Dominique Rigal Yves Bertrand Els Goulmy Assia Eljaafari 《Biology of blood and marrow transplantation》2006,12(11):1114-1124
In vitro stimulation of human female T cells with male HLA-identical dendritic cells resulted in the generation of HLA-DQB1*0501/0502-restricted minor histocompatibility H-Y antigen-specific CD4(+) T cell clones. Two clones generated from different HLA-identical pairs were analyzed. Use of HLA-DQ5-expressing female Epstein-Barr virus transformed B lymphoblastoid cell lines transfected with various H-Y genes and loaded with overlapping peptides demonstrated that both T cell clones are specific for a peptide encoded by DDX3Y. Previously, an HLA-DQ5-restricted T cell clone specific for the same peptide was isolated from a patient with graft-versus-host disease. Thus, we compared the T cell receptor (TCR) rearrangements of the 2 in vitro generated T cell clones and the ex vivo isolated T cell clone. All 3 clones shared the same TCRBV5-4* gene segment and 2 of 3 clones also used similar TCR-Valpha segments. Our results suggest that T cells recognizing the HLA-DQ5/DDX3Y T cell epitope might be characterized by a relatively limited TCR-beta repertoire. The differences in the junctional TCR-beta region had no effect on the antigen specificity, but altered the capacity of the TCR to distinguish the HLA-DQ5/DDX3Y complex from its allelic counterpart. The results also demonstrate that in vitro stimulation of T cells with allogeneic HLA-identical dendritic cells may facilitate the characterization of in vivo, potentially relevant HLA class II-restricted minor H epitopes. 相似文献