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排序方式: 共有803条查询结果,搜索用时 15 毫秒
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Regional myocardial dysfunction: evaluation of patients with prior myocardial infarction with fast CT 总被引:1,自引:0,他引:1
Lipton MJ; Farmer DW; Killebrew EJ; Bouchard A; Dean PB; Ringertz HG; Higgins CB 《Radiology》1985,157(3):735-740
A prototype ultrafast cine computed tomographic (CT) scanner, designed specifically for cardiac imaging, was used to evaluate a preliminary series of patients with prior myocardial infarction (n = 21) and a control group without coronary artery disease (n = 5). Multilevel 50-msec CT scan exposures were obtained during peripheral intravenous bolus injections of contrast medium. A comparison was made between cine-CT scans and standard left ventriculographic images in assessing segmental left ventricular motion. Results indicate that cine CT, performed at sufficiently rapid speeds (20 scans per second) to allow useful analysis of regional ventricular wall motion, can provide adequate image quality. Analysis of 110 segments revealed a good correlation (90.9%) between the two techniques in characterizing normal from abnormal regional wall motion. Cine CT, based on this initial study, demonstrates considerable potential for evaluating not only cardiac chamber dimensions but also segmental wall dynamics. 相似文献
33.
A number of surgical clips and other metallic materials embedded within patients have ferromagnetic properties that present a potential hazard when in the strong fields associated with magnetic resonance imaging. Several types of magnetometers and metal detectors were investigated as possible pre-imaging screening devices. The sensitivities and costs of these devices are given. 相似文献
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Cellular immunotherapy after allogeneic stem cell transplantation in hematologic malignancies 总被引:2,自引:0,他引:2
PURPOSE OF REVIEW: The chimeric state after allogeneic stem cell transplantation provides an ideal platform for adoptive immunotherapy of hematologic malignancies using donor-derived cells. The present review aims to summarize recent results of the transfusion of donor-derived cells with regard to the diseases treated, the cells used for treatment, and the origin of these cells. RECENT FINDINGS: The transfusion of donor lymphocytes has been studied widely, not only in patients with recurrent disease, persistent disease, and mixed chimerism but also in a variety of hematologic malignancies. Donors of lymphocytes and hematopoietic stem cells have been HLA-identical siblings, HLA-matched unrelated donors, and HLA-different haploidentical family members. A variety of cells have been used for adoptive immunotherapy, including plain lymphocytes, selected T cells, T cell lines, and T cell clones. The possible therapies have been expanded by natural killer cells and natural killer T cells as well as antibodies directing the effector cells toward the malignancy. SUMMARY: Adoptive immunotherapy in chimeras has become not only a routine form of treatment of recurrent hematologic malignancy but also a prophylactic measure in high-risk leukemia and lymphoma. 相似文献
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Defense factors of vaginal lactobacilli 总被引:12,自引:0,他引:12
Aroutcheva A Gariti D Simon M Shott S Faro J Simoes JA Gurguis A Faro S 《American journal of obstetrics and gynecology》2001,185(2):375-379
OBJECTIVE: To determine the antagonistic relationship between vaginal lactobacilli and endogenous vaginal microflora. STUDY DESIGN: Twenty-two Lactobacillus strains were studied for the production of lactic acid, hydrogen peroxide, and bacteriocin. RESULTS: Under standardized growth conditions, most strains increased their biomass by more than 4 times. Lactobacillus species grew best at a pH > or = 4.5, and growth was retarded at a pH < 4.5. Lactic acid levels were 0.68 to 2.518 mg/mL and were not related to the number of cells or the pH of media. The pH of the media was caused by the secretion of lactic and other organic acids. Approximately 80% of the strains produced H(2)O(2) and were graded as 2+ in one third of the strains and 1+ in others. No statistical correlation was found between H(2)O(2) lactic acid and bacteriocin production. Bacteriocin activity was tested on 4 strains of Gardnerella vaginalis. Approximately 80% of the lactobacilli tested produced bacteriocin that inhibited growth of G vaginalis. Six of the strains did not produce bacteriocin. Thirteen strains produced all 3 defense factors, whereas the others lacked 1 or 2 properties. CONCLUSIONS: Lactobacillus species grow best at a pH > 4.5. The pH of the media is dependent on the cell mass and on all organic acids produced by Lactobacillus species. Although all species produce organic acids, not all produce H(2)O(2) and bacteriocin. Not all strains of G vaginalis can be inhibited by lactobacilli-producing bacteriocin. 相似文献
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Fifteen infants with life-threatening gastrointestinal anomalies received total parenteral feeding for periods ranging from 10 to 54 days; their ages ranged from one day to 5 months. The solutions were administered through peripheral veins. All patients gained weight during the period of observation and no cases of septicaemia were encountered. 相似文献