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排序方式: 共有593条查询结果,搜索用时 15 毫秒
51.
52.
Jung Nathalie Namjoshi Sarika Mohammed Yousuf Grice Jeffrey E. Benson Heather A. E. Raney Sam G. Roberts Michael S. Windbergs Maike 《Pharmaceutical research》2022,39(5):935-948
Pharmaceutical Research - The quality testing and approval procedure for most pharmaceutical products is a streamlined process with standardized procedures for the determination of critical quality... 相似文献
53.
Primary cutaneous anaplastic large cell lymphoma in a young girl 总被引:1,自引:0,他引:1
54.
Felicity NE Gavins Helen K Smith 《Journal of cerebral blood flow and metabolism》2015,35(7):1090-1099
Stem cell therapy has showed considerable potential in the treatment of stroke over the last decade. In order that these therapies may be optimized, the relative benefits of growth factor release, immunomodulation, and direct tissue replacement by therapeutic stem cells are widely under investigation. Fundamental to the progress of this research are effective imaging techniques that enable cell tracking in vivo. Direct analysis of the benefit of cell therapy includes the study of cell migration, localization, division and/or differentiation, and survival. This review explores the various imaging tools currently used in clinics and laboratories, addressing image resolution, long-term cell monitoring, imaging agents/isotopes, as well as safety and costs associated with each technique. Finally, burgeoning tracking techniques are discussed, with emphasis on multimodal imaging. 相似文献
55.
IOANNIS THEODOROU CLAUDE BIGORGNE MARIE-HLNE DELFAU CHANTAL LAHET GILLES COCHET MICHEL VIDAUD MARTINE RAPHAEL PHILIPPE GAULARD JEAN-PIERRE FARCET 《The Journal of pathology》1996,178(3):303-310
Using Southern blotting for the diagnosis of clonality in peripheral T-cell lymphomas (PTCLs), analysis of the T-cell receptor (TCR) γ gene rearrangement was shown to be more informative than that of the TCR β gene rearrangement. In order to amplify every VJγ rearrangement, a polymerase chain reaction (PCR) procedure using newly designed GC-clamp primers has been developed. All primers can be mixed in a single multiplex PCR. PCR products are analysed by denaturing gradient gel electrophoresis (DGGE), providing tumour-specific imprints inasmuch as the procedure characterizes N sequence polymorphism at the VJ junctions. In a series of 30 PTCL cases, the PCR procedure demonstrated 27 cases to be clonally rearranged and failed in three cases. PCR was more accurate than Southern blotting, showing 47 rearranged γ alleles, four of which were undetectable on the Southern blot. When lymphomas were studied at different sites and at relapse, the DGGE pattern remained unchanged. In PTCL, the proposed PCR is helpful for the diagnosis and staging of the disease and should improve the follow-up monitoring. The undetectability of clonal rearrangements in a few cases is discussed in the light of concepts of lymphomagenesis and T-cell differentiation. 相似文献
56.
This report describes the results of bone marrow leukocyte immunophenotypic studies, DNA index measurement, and chromosome analysis in a newborn with Down syndrome and transient myeloproliferative disorder. The infant's initial leukocytosis with immature cells in the peripheral blood and thrombocytopenia resolved without treatment by 6 months of age, and he was well at 2 years of age. The lack of specific reactivity between the patient's morphologically immature cells and multiple monoclonal antibodies directed against lymphoid and myeloid leukemia cells may be characteristic of this disorder. Other cases should be examined for immunophenotype to correlate the results with chromosomal analysis and to provide a basis for comparison in those who subsequently develop true acute leukemia. 相似文献
57.
JM Langley JC LeBlanc EE Wang BJ Law NE MacDonald I Mitchell D Stephens J McDonald FD Boucher S Dobson 《Pediatrics》1997,100(6):943-946
OBJECTIVE: To determine nosocomial transmission of respiratory syncytial virus (RSV) in Canadian pediatric hospitals, outcomes associated with nosocomial disease, and infection control practices. DESIGN: A prospective cohort study in the 1992 to 1994 winter respiratory seasons. SETTING: Nine Canadian pediatric university-affiliated hospitals. PARTICIPANTS: Hospitalized children with symptoms of lower respiratory tract infection (at least one of cough, wheezing, dyspnea, tachypnea, and apnea) and RSV antigen identified in a nasopharyngeal aspirate. RESULTS: Of 1516 children, 91 (6%) had nosocomial RSV (NRSV), defined as symptoms of lower respiratory tract infection and RSV antigen beginning >72 hours after admission. The nosocomial ratio (NRSV/[com-munity-acquired RSV {CARSV})] + NRSV) varied by site from 2.8% to 13%. The median length of stay attributable to RSV for community-acquired illness was 5 days, but 10 days for nosocomial illness. Four children with NRSV (4. 4%) died within 2 weeks of infection, compared with 6 (0.42%) with CARSV (relative risk = 10.4, 95% confidence interval: 3.0, 36.4). All sites isolated RSV-positive patients in single rooms or cohorted them. In a multivariate model, no particular isolation policy was associated with decreased nosocomial ratio, but gowning to enter the room was associated with increased risk of RSV transmission (incidence rate ratio 2.81; confidence interval: 1.65, 4.77). CONCLUSIONS: RSV transmission risk in Canadian pediatric hospitals is generally low. Although use of barrier methods varies, all sites cohort or isolate RSV-positive patients in single rooms. Children with risk factors for severe disease who acquire infection nosocomially have prolonged stays and excess mortality. 相似文献
58.
A R Rajakumar K Prasad S V Mantha M Khouri B Raney 《The Canadian journal of cardiology》1999,15(9):989-998
BACKGROUND: Oxygen free radicals (OFRs) have been implicated in ischemic-reperfusion cardiac injury. Use of percutaneous transluminal coronary angioplasty (PTCA) has created renewed interest in salvation of ischemic myocardium. The PTCA procedure is similar to the ischemia-reperfusion model. It is possible that OFRs are increased following PTCA. However, OFR-related cardiac complications are uncommon and the evidence for lipid peroxidation is conflicting. PATIENTS AND METHODS: In this study the levels of plasma malondialdehyde, OFR-producing activity of polymorphonuclear leukocytes (PMNL-CL) and blood antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) were measured in peripheral venous blood of 50 consecutive patients with stable angina undergoing elective PTCA. The ability of Isovue (used during PTCA) and of streptokinase (used during thrombolysis) to scavenge OH in the high performance liquid chromatography method and to reduce OH-induced lipid peroxidation were also assessed. Patients were divided into three groups: group 1, single vessel PTCA; group 2, two or more vessel PTCA; and group 3, combined single and multivessel PTCA. RESULTS: The results indicated that there was an increase in PMNL-CL (22% to 44%) and a decrease in plasma malondialdehyde (33% to 40%) at 60 mins following PTCA. The activity of antioxidant enzymes remained unaltered. Isovue scavenged OH in a concentration-dependent manner and was complete at a concentration below that used in patients. Streptokinase, on the other hand, was ineffective in scavenging OH. CONCLUSIONS: These results suggest that, in spite of increased production of OFR by polymorphonuclear leukocytes and unaltered activity of antioxidant enzymes, lipid peroxidation decreased. Lack of lipid peroxidation may have been due to the OH-scavenging property of Isovue. The observed differences in OFR-related complications between PTCA and thrombolytic therapy may have been due to the antioxidant activity of Isovue. 相似文献
59.
60.
R Heyn R B Raney D M Hays M Tefft E Gehan B Webber H M Maurer 《Journal of clinical oncology》1992,10(4):614-623
PURPOSE: We report on long-term health-related problems determined from extended follow-up of 86 children and adolescents who were treated for paratesticular rhabdomyosarcoma on the Intergroup Rhabdomyosarcoma Studies I and II (IRS I-II). PATIENTS AND METHODS: Patients were treated between 1972 and 1984, and ages at diagnosis ranged from 10 months to 19 years. The majority of these patients had initial retroperitoneal lymph node dissection (RLND) or sampling performed. RESULTS: Problems related to surgical procedures included bowel obstruction in nine patients, loss of normal ejaculatory function in eight, development of a hydrocele in five, and lymphedema of the leg in five. Sequelae related to radiotherapy were difficult to assess with the exception of three patients whose remaining testes were in the field of radiotherapy. In general, kidney and bladder function were normal in patients who received radiotherapy to the paraaortic lymph nodes and/or bladder. Four patients who had abdominal radiotherapy had chronic diarrhea. Two patients had urethral strictures and urethritis. Four patients had bone or soft tissue hypoplasia in the field of radiotherapy. Chemotherapy-related late effects were primarily hemorrhagic cystitis or gonadal dysfunction after cyclophosphamide. A third of the patients who received cyclophosphamide developed hemorrhagic cystitis, and half of these had extended periods of gross hematuria after therapy was discontinued. The testicular size was small in children whose testes were irradiated and in some who received cyclophosphamide. Tanner staging was normal in 45 patients for whom it was recorded. Elevated follicle-stimulating hormone (FSH) values or known azoospermia occurred in more than half the patients for whom data were available. CONCLUSIONS: A variety of sequelae related to therapy were determined in this patient population. These findings suggest that some aspects of therapy warrant reevaluation and that improved plans for follow-up care need to be provided. 相似文献