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991.
Neurofibromatosis type 1 and sporadic optic gliomas.   总被引:2,自引:0,他引:2  
AIMS: To compare the natural history of sporadic optic glioma with those associated with neurofibromatosis type 1 (NF1). METHODS: Optic glioma cases were identified using both the Manchester Children's Tumour Registry (CTR) and the North West Regional NF1 Database (NF1DB), with detailed information on natural history available from the former (in 34 of 36 cases identified). RESULTS: A total of 52 cases over a period of 41 years were identified. From the 34 whose natural history was known, almost all (n = 31) were symptomatic, with mean ages of presentation of 4.5 and 5.1 years for NF1 and sporadic cases respectively. The majority (n = 22) presented with visual impairment, seven of whom were blind in at least one eye. Sporadic cases were over twice as likely as NF1 to have visual impairment. Recurrence occurred in 12 patients. Fewer NF1 patients died as a direct result of their optic glioma, but overall mortality and 5 and 10 year survival rates between the two groups were similar. All five primary (non-metastatic) second central nervous system (CNS) tumours occurred in NF1 cases, two of these following radiotherapy. CONCLUSIONS: Symptomatic sporadic optic gliomas presented with impaired vision more frequently and were more aggressive than NF1 optic gliomas. Only optic glioma cases with NF1 were at risk of developing a second CNS tumour. Aggressive treatment of sporadic optic gliomas and early surveillance of NF1 optic gliomas may be required. The use of radiotherapy in these children requires further clarification.  相似文献   
992.
993.
Migration of blood-borne lymphocytes into lymphoid tissues and sites of inflammation is initiated by vascular adhesion molecules and proinflammatory cytokines. Previous in vivo studies have shown that febrile temperatures dynamically stimulate adhesion in differentiated high endothelial venules (HEV), which are portals for lymphocyte extravasation. This report examines the direct effect of fever-range hyperthermia on the expression of adhesion molecules and cytokines by primary cultured endothelial cells. In both macrovascular (HUVEC) and microvascular (HMVEC) endothelial cells, fever-range hyperthermia (40 degrees C for 6-12 h) did not affect expression of adhesion molecules (ICAM-1, E-selectin, VCAM-1, P-selectin, PECAM-1, PNAd, MAdCAM-1), cytokine release (IL-1beta, TNF-alpha, IFN-gamma, IL-6, IL-11, IL-12, IL-13), or chemokine secretion (IL-8, RANTES, MCP-1, MIP-1beta, MIG). This is in contrast to the stimulatory effects of TNF-alpha or 43 degrees C heat shock. However, a novel role for fever-range hyperthermia was identified in augmenting actin polymerization in cultured endothelial cells and enhancing the ability of endothelial-derived factors to transactivate the alpha4beta7 integrin lymphocyte homing receptor. These findings provide insight into the tightly regulated effects of fever-range hyperthermia that exclude induction of adhesion in non-activated endothelium of normal blood vessels. Through these mechanisms, it is proposed that febrile temperatures associated with infection or clinical hyperthermia avoid the unproductive exodus of lymphocytes to non-involved extralymphoid tissues while simultaneously promoting lymphocyte delivery to sites of immune activation.  相似文献   
994.
PURPOSE: Liposomal anthracyclines and paclitaxel are considered the best available cytotoxic therapies for Kaposi's sarcoma (KS), but relapse is common. To identify new interventions for relapsed or progressive KS, a phase II study of low-dose etoposide to assess its toxicity and efficacy was conducted. PATIENTS AND METHODS: Thirty-six patients with high-risk KS were treated with oral etoposide 50 mg/d for 7 consecutive days of every 2-week cycle. All patients' disease had relapsed or progressed after prior combination chemotherapy or anthracycline therapy. For patients without a complete or partial response after two cycles of therapy and no toxicity greater than grade 2, the dose of etoposide was escalated to 100 mg/d orally on days 1 to 7 of each 14-day cycle. Treatment-related and disease-specific quality of life was evaluated using patient reports on the General Health Self-Assessment Form and a KS-specific measure. RESULTS: One patient achieved a complete response, 12 patients had a partial response (overall response rate, 36.1%), and stable disease was observed in 12 patients (33.3%). Tumor responses were seen in all disease sites. Fourteen patients had their dose escalated, of whom five responded. The median time to response was 17.7 weeks; the median duration of response was 25 weeks. The most frequent hematologic abnormality was neutropenia, which was grade 4 in seven patients and grade 3 in six. Opportunistic infections occurred in eight patients during the treatment period. Both response to treatment and toxicity influenced patient-reported quality of life. CONCLUSION: We conclude that low-dose oral etoposide at a dose of 50 mg/d is safe and effective for the treatment of refractory or progressed AIDS-related KS and has an overall positive effect on the quality of life of responding patients.  相似文献   
995.
PURPOSE: To determine whether granulocyte-macrophage colony-stimulating factor (GM-CSF) would improve response to influenza vaccination in cancer patients. PATIENTS AND METHODS: In a randomized, patient-blinded, placebo-controlled trial carried out in 1997 to 2000, 133 patients were stratified into five groups of treatment and disease. Single doses of standard split trivalent influenza vaccine and either placebo or 250 micro g of GM-CSF were administered at the same time. Hemagglutination inhibition assay titers were measured before and 4 weeks after vaccination. RESULTS: Standard analyses, which define response as at least a four-fold increase in titers, detect no effect of GM-CSF for any of the three influenza subtypes in the trivalent vaccines (P >or=.12). Analysis that includes the magnitude of the change in titers and combines responses of the subtypes suggests that the placebo group had the greater response (P =.051), thus indicating that GM-CSF does not improve response. Ancillary analyses show that response declines both with increasing age and with higher initial titers. The fraction of patients with at least a four-fold increase in titers was 0.36 (95% confidence interval, 0.29 to 0.42) CONCLUSION: A single 250- micro g dose of GM-CSF administered with the influenza vaccine does not improve response to vaccination. Response in cancer patients is low and declines as age and initial titer increase.  相似文献   
996.
Studies investigating the relationship between the use of inflectional morphology and speech-perception abilities in children with SLI traditionally have employed synthetic speech stimuli. The purpose of this study was to replicate the findings reported in Leonard, McGregor, and Allen (1992) with an older group of children with SLI and to determine if the pattern of deficits seen for synthetic speech extends to perception of natural speech stimuli. The speech-perception abilities of 27 children between the ages of 6;11 and 8;11 (15 SLI and 12 NL) were compared using natural and synthetic versions of the [das]-[daS], [dabiba]-[dabuba], and [i]-[u] contrast pairs originally used in Leonard et al. The findings reported by Leonard et al. were replicated with synthetic speech but not for the natural speech. Use of inflectional morphology in obligatory contexts by the children with SLI was not significantly correlated with their perception abilities for any of the natural or synthetic speech-contrast pairs. Further, although both groups' ability to maintain the target contrast in memory declined over the span of the trials for all target contrasts for both natural and synthetic speech, the rate of decline did not differ significantly between the SLI and NL groups. Findings are discussed with respect to possible deficits in linking phonological representations to grammatical representations in children with SLI.  相似文献   
997.
Background: When implemented in several common surgical procedures, clinical pathways have been reported to reduce costs and resource utilization, while maintaining or improving patient care. However, there is little data to support their use in more complex surgery. The objective of this study was to determine the effects of clinical pathway implementation in patients undergoing elective pancreaticoduodenectomy (PD) on cost and resource utilization.Methods: Outcome data from before and after the development of a clinical pathway were analyzed. The clinical pathway standardized the preoperative outpatient care, critical care, and postoperative floor care of patients who underwent PD. An independent department determined total costs for each patient, which included all hospital and physician costs, in a blinded review. Outcomes that were examined included perioperative mortality, postoperative morbidity, length of stay, readmissions, and postoperative clinic visits.Results: From January, 1996 to December, 1998, 148 consecutive patients underwent PD or total pancreatectomy; 68 before pathway development (PrePath) and 80 after pathway implementation (PostPath). There were no significant differences in patient demographics, comorbid conditions, underlying diagnosis, or use of neoadjuvant therapy between the two groups. Mean total costs were significantly reduced in PostPath patients compared with PrePath patients ($36,627 vs. $47,515; P = .003). Similarly, mean length of hospital stay was also significantly reduced in PostPath patients (13.5 vs. 16.4 days; P = .001). The total cost differences could not be attributed solely to differences in room and board costs. Cost and length-of-stay differences remained when outliers were excluded from the analysis. Despite these findings, there were no significant differences between PrePath and PostPath patients in terms of perioperative mortality (3% vs. 1%), readmissions within 1 month of discharge (15% vs. 11%), or mean number of clinic visits within 90 days of discharge (3.3 vs. 3.4 visits).Conclusions: The establishment of a clinical pathway for PD patients dramatically reduced costs and resource utilization without any apparent detrimental effect on quality of patient care. These findings support the implementation of clinical pathways for PD patients, as well as investigation into pathway care for other complex surgical procedures.  相似文献   
998.
During long-term spaceflight, astronauts lose bone, in part due to a reduction in bone formation. It is not clear, however, whether the force imparted by gravity has direct effects on bone cells. To examine the response of bone forming cells to weightlessness, human fetal osteoblastic (hFOB) cells were cultured during the 17 day STS-80 space shuttle mission. Fractions of conditioned media were collected during flight and shortly after landing for analyses of glucose utilization and accumulation of type I collagen and prostaglandin E(2) (PGE(2)). Total cellular RNA was isolated from flight and ground control cultures after landing. Measurement of glucose levels in conditioned media indicated that glucose utilization occurred at a similar rate in flight and ground control cultures. Furthermore, the levels of type I collagen and PGE(2) accumulation in the flight and control conditioned media were indistinguishable. The steady-state levels of osteonectin, alkaline phosphatase, and osteocalcin messenger RNA (mRNA) were not significantly changed following spaceflight. Gene-specific reductions in mRNA levels for cytokines and skeletal growth factors were detected in the flight cultures using RNase protection assays. Steady-state mRNA levels for interleukin (IL)-1alpha and IL-6 were decreased 8 h following the flight and returned to control levels at 24 h postflight. Also, transforming growth factor (TGF)-beta(2) and TGF-beta(1) message levels were modestly reduced at 8 h and 24 h postflight, although the change was not statistically significant at 8 h. These data suggest that spaceflight did not significantly affect hFOB cell proliferation, expression of type I collagen, or PGE(2) production, further suggesting that the removal of osteoblastic cells from the context of the bone tissue results in a reduced ability to respond to weightlessness. However, spaceflight followed by return to earth significantly impacted the expression of cytokines and skeletal growth factors, which have been implicated as mediators of the bone remodeling cycle. It is not yet clear whether these latter changes were due to weightlessness or to the transient increase in loading resulting from reentry.  相似文献   
999.
1000.
OBJECTIVES: To evaluate a paging system designed to improve independence in people with memory problems and executive deficits. METHODS: After a successful pilot study, a randomised control trial was conducted involving a crossover design with 143 people aged between 8 and 83 years. All had one or more of the following: memory, planning, attention, or organisation problems. Most had sustained a traumatic head injury or a stroke although a few had developmental learning difficulties or other conditions. The crossover design ensured that some people received a pager after a 2 week baseline whereas others were required to wait for 7 weeks after the baseline before receiving the pager. Participants were assessed at three time periods-namely, at baseline, 7 weeks, and at 14 weeks postbaseline. RESULTS: More than 80% of those who completed the 16 week trial were significantly more successful in carrying out everyday activities (such as self care, self medication, and keeping appointments) when using the pager in comparison with the baseline period. For most of these, significant improvement was maintained when they were monitored 7 weeks after returning the pager. CONCLUSIONS: This particular paging system significantly reduces everyday failures of memory and planning in people with brain injury.  相似文献   
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