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981.
Combination therapy of an orthotopic renal cell carcinoma model using intratumoral vector-mediated costimulation and systemic interleukin-2. 总被引:2,自引:0,他引:2
Chie Kudo-Saito Elizabeth K Wansley M Eilene Gruys Robert Wiltrout Jeffrey Schlom James W Hodge 《Clinical cancer research》2007,13(6):1936-1946
PURPOSE: Interleukin (IL)-2 therapy is currently used for therapy of renal cell carcinoma (RCC). However, it is only effective in approximately 10% to 15% of patients, showing a need for additional therapies. We have previously described a replication-defective fowlpox vector encoding three costimulatory molecules (B7-1, ICAM-1, and LFA-3), designated rF-TRICOM. Here, we show that intratumoral administration of rF-TRICOM in an orthotopic RCC model effectively enhances tumor immunogenicity and reduces tumor burden in mice and the combination of rF-TRICOM and IL-2 is more effective than either therapy alone. EXPERIMENTAL DESIGN: RCC cells were implanted under the capsule of the kidney, and mice were given rF-TRICOM intratumorally 14 days later. We compared the effect of rF-TRICOM, rF-granulocyte macrophage colony-stimulating factor (GM-CSF), and two doses of IL-2 and combinations of the above on antitumor efficacy and survival. Host CD4(+) and CD8(+) T-cell responses were also evaluated. RESULTS: The results show that (a) systemic IL-2 therapy was moderately effective in the reduction of tumor burden in an orthotopic RCC model; (b) a single intratumoral injection of rF-TRICOM and rF-GM-CSF significantly reduced tumor burden; (c) the addition of systemic IL-2 to intratumoral rF-TRICOM/rF-GM-CSF administration resulted in further reduction of tumor burden, decrease in the incidence of metastasis, and extended survival in tumor-bearing mice above that seen with either treatment alone; and (d) CD8(+) T cells played a critical role in the antitumor effect seen with rF-TRICOM/rF-GM-CSF + IL-2 therapy. Finally, the addition of systemic recombinant IL-15 or intratumoral vector-delivered IL-15 to intratumoral rF-TRICOM/rF-GM-CSF administration resulted in substantially more tumor-free mice than either therapy alone. CONCLUSIONS: These studies show that intratumoral administration of rF-TRICOM admixed with rF-GM-CSF is effective at reducing tumor burden in mice and the addition of IL-2 further contributes to this effect. These studies thus form the rationale for combination immunotherapy clinical trials in patients with RCC. 相似文献
982.
Vivian A. Blacker James P. McLennan 《Australian and New Zealand journal of public health》1987,11(1):31-37
This paper reports a survey of program evaluation and service monitoring activity in 49 Victorian community health centres. Centres generally have not made evaluation and monitoring an important part of their operations despite the rhetoric of health services policy makers and administrators. Reasons for this include a lack of staff in centres who are trained in evaluation methods; the reluctance of centre staff to divert time and resources from service provision to evaluation; and insufficient assistance to centres from the Health Commission of Victoria. “The assumptions that operating a service is equivalent to rendering service and that both are equivalent to rendering quality service are no longer being honoured as inherently valid.”1 相似文献
983.
984.
Severe deficiency of acid ceramidase activity (4-5% of normal) was demonstrated in cultured skin fibroblasts, leukocytes and plasma from a 1-year-old boy who was diagnosed as being affected with Farber disease. Determination of ceramidase activity in plasma was achieved by a highly sensitive assay employing a ceramide substrate containing radiolabeled C12 N-acyl moiety (N-lauryl). The enzyme activity in the parents' leukocytes and plasma was found to be reduced to 18-47% of the respective normal values, and that determined in a plasma specimen from a patient with I-cell disease was about 4 times elevated above the normal level. 相似文献
985.
The surface of the ovary has been found to be composed of two types of epithelial cells called A and B cells which are found in their own respective zones, the A and B zones. A quantitative study was undertaken to determine the mean cell volumes and cell ultrastructure. Ovarian biopsies were taken from six women and A and B zones, having been identified by scanning electron microscopy, were re-embedded for transmission electron microscopy. Stereological measurements using point sampled intercepts were made on vertical sections and showed that B cells are significantly larger than A cells. The volume weighted mean cell volumes of the A and B cells were 237.3 microns 3 and 676.8 microns 3 respectively. The volume fractions of the nucleus and mitochondria were similar in the two cell types. Although the vesicle content of each type was similar, a large variation between cases made the interpretation difficult. The stereological tools used in this study proved to be easy and efficient estimators of surface cell ultrastructure and give an important direction for ultrastructural research. 相似文献
986.
Narrative and procedural discourse in temporal lobe epilepsy. 总被引:2,自引:0,他引:2
Brian Bell Christian Dow E Ryann Watson Austin Woodard Bruce Hermann Michael Seidenberg 《Journal of the International Neuropsychological Society》2003,9(5):733-739
It is well established that some individuals with temporal lobe epilepsy (TLE) demonstrate language deficits at the single word level. However, discourse production rarely has been examined quantitatively within this group. This study compared adult TLE patients with an early seizure onset (< or = age 14 years, n = 27) to a control group (n = 28) on narrative and procedural discourse tasks. As a group, the TLE patients performed normally on the procedural discourse task, but differed significantly from the controls on several narrative discourse variables. At the individual level, 30% of the TLE patients versus 4% of the controls demonstrated impaired discourse ability (p and 0.01). Within this early onset TLE group, discourse performance was not associated with demographic or seizure history variables. Considering the cognitive domain, discourse performance correlated significantly with working memory. In summary, mild discourse dysfunction was present in a significant minority of early onset TLE patients, but this deficit was not closely associated with other language measures. Discourse ability and its neuropsychological, neuroanatomical and conversational speech correlates deserve further study in TLE patients. 相似文献
987.
The purposes of this study were to discover the essences of the experience of waiting, to provide new knowledge about what it is like to wait, and to contribute to nursing knowledge. Participants were 12 persons who were family members or friends of persons in an adult critical care unit. The Parse research method was used to answer the research question: What is the structure of the lived experience of waiting? The central finding of this study was this structure: The lived experience of waiting is a vigilant attentiveness surfacing amid an ambiguous turbulent lull as contentment emerges with uplifting engagements. The structure is discussed in relation to nursing knowledge and in relation to how it can inform future research and practice. © 2002 John Wiley & Sons, Res Nurs Health 25:58–67, 2002. 相似文献
988.
Phil Tibbo C J de Gara Treena M Blake Carolyn Steinberg Brian Stonehocker 《Revue canadienne de psychiatrie》2002,47(6):562-567
OBJECTIVE: To examine the perceptions of intimidation in the psychiatric educational environment in Edmonton, Alberta. METHODS: We distributed a 7-point modified Likert scale questionnaire that included questions with respect to intimidation perceptions and experience in psychiatry during a 1-week period to all student interns on psychiatry rotations, residents, and teaching faculty in the 5 teaching hospitals in Edmonton. RESULTS: A total of 92 individuals responded, with response rates of 81% for faculty, 82% for residents, and 84% for students. Response rates did not differ among sites. While there were differences between site and group with respect to comparing the perceived intimidation in psychiatry with other specialties, respondents did not view psychiatry as worse than other specialties. Although, overall, women perceived intimidation as more prevalent at their sites than did men, the overall means reflect sites that are relatively free from intimidation. Faculty and student interns within sites, except for the university hospital, tended to disagree on management's approach to perceived intimidation. All groups, however, reported little personal experience and felt their sites had little tolerance for intimidators. CONCLUSIONS: Reported perceptions and personal experiences of intimidation within the psychiatric learning environment in Edmonton are low. 相似文献
989.
990.
Anucha Apisarnthanarak Marilyn Jones Brian M Waterman Cathy M Carroll Robert Bernardi Victoria J Fraser 《Infection control and hospital epidemiology》2003,24(1):31-36
OBJECTIVE: To characterize risk factors for surgical-site infection after spinal surgery. DESIGN: A case-control study. SETTING: A 113-bed community hospital. METHOD: From January 1998 through June 2000, the incidence of surgical-site infection in patients undergoing laminectomy, spinal fusion surgery, or both increased at community hospital A. We compared 13 patients who acquired surgical-site infections after laminectomy, spinal fusion surgery, or both with 47 patients who were operated on during the same time period but did not acquire a surgical-site infection. Information collected included demographics, risk factors, personnel involved in the operations, length of hospital stay, and hospital costs. RESULTS: Of 13 case-patients, 9 (69%) were obese, 9 (69%) had spinal compression, 5 (38.5%) had a history of tobacco use, and 4 (31%) had diabetes. Oxacillin-sensitive Staphylococcus aureus (6 of 13; 46%) was the most common organism isolated. Significant risk factors for postoperative spinal surgical-site infection were dural tear during the surgical procedure and the use of glue to cement the dural patch (3 of 13 [23%] vs 1 of 47 [2.1%]; P = .02) and American Society of Anesthesiologists risk class of 3 or more (6 of 13 [46.2%] vs 7 of 47 [15%]; P = .02). Case-patients were more likely to have prolonged length of stay (median, 16 vs 4 days; P< .001). The average excess length of stay was 11 days and the excess cost per case was $12,477. CONCLUSION: Dural tear and the use of glue should be evaluated as potential risk factors for spinal surgical-site infection. Systematic observation for potential lapses in sterile technique and surgical processes that may increase the risk of infection may help prevent spinal surgical-site infection. 相似文献