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51.
目的 研究Ewing’s肉瘤细胞系 (RM 82 )X 射线外照射后肿瘤坏死因子 (TNF α)和转化生长因子 (TGF β)mRNA表达水平的变化 ,探讨X 射线诱导内源性TNF α和TGF β产生的可能性及意义。 方法 应用实时荧光RT PCR ,检测接受不同剂量X 线照射 (2Gy ,5Gy ,10Gy ,2 0Gy ,30Gy ,4 0Gy)和受照后不同时间 (1h ,3h ,6h ,12h ,2 4h ,4 8h ,72h)。TNF α和TGF βmRNA表达水平的变化。 结果 RM 82细胞TNF αmRNA表达水平较外照射前显著升高。一方面受照后TNF αmRNA表达逐渐升高 ,照射剂量达 4 0Gy时TNF αmRNA表达水平达高峰 ,为正常对照组的 10 8倍 ;另一方面 ,照射后 3h后TNF αmRNA表达逐渐升高 ,6h达高峰 ,为正常对照组的 18倍。相反 ,TGF βmRNA表达水平X 射线照射前后无显著变化。结论 Ewing’s肉瘤细胞系 (RM 82 )接受X 线照射后TNF αmRNA表达明显升高 ,且呈现时间、剂量依赖性。放射治疗可诱导Ewing’s肉瘤细胞系 (RM 82... 相似文献
52.
BACKGROUND: For patients with chronic myeloid leukemia (CML), long-term survival after stem cell transplantation requires adequate control of graft-versus-host disease (GVHD) and disease recurrence. Relapsing patients respond to donor lymphocyte infusion (DLI) but develop life-threatening complications. METHODS: Patients with CML in first chronic phase received bone marrow (n = 14) or peripheral blood progenitor cell transplants (n = 4) from HLA-identical siblings. GVHD prophylaxis was by ex vivo T-cell depletion with CAMPATH 1G. If disease recurred, donors' mononuclear cells were collected by apheresis, the CD3 samples commencing at 10(6)/kg were aliquoted at half-log increment intervals, cryopreserved, and infused until disease clearance. RESULTS: Eighteen patients (median age: 32.5 years) received transplants. All engrafted without procedure-related mortality. Fourteen patients relapsed, and 13 entered the DLI program. Two developed extensive GVHD after single schedule infusions ranging from 89x10(6) to 670x10(6) mononuclear cells/kg, and one survives in complete remission (CR). The rest, treated with incremental dose DLI, experienced no acute toxicities. One, who had developed grade III steroid-responsive GVHD, died in CR2 from opportunistic infections. Steroids reversed limited cutaneous GVHD and elevated liver enzymes in five patients. Three others developed pancytopenia, and two restored blood counts only after donor peripheral blood progenitor cell infusions. Molecular CR2 was established in 12/13 patients, occurring in 10/11 (91%) on the incremental program at a median accumulation of 67 (range: 5-166) x10(6) CD3 cells/kg. Sixteen of 18 (89%) survive at median of 854.5 days from bone marrow transplantation, 4 in CR1 and 10 in CR2 at a median disease-free survival (for remission 2) duration of 341 days. The median combined disease-free survival of the 14 patients in CR 1+2 is 660 days, with 99% average performance status. CONCLUSIONS: Escalating DLI leads to safe new molecular CR in most CML relapse patients. These results raise the possibility of using "safe" transplantation programs of T-cell depletion, that include graded DLI as prevention against disease recurrence. 相似文献
53.
Higher fat and energy intakes confer a survival advantage in cystic fibrosis (CF). There is a need to develop effective nutrition programmes that ensure optimal energy intake in CF.
A cross-sectional measurement of clinical characteristics and energy and fat intakes in patients attending the CF outpatients clinic of the John Hunter Hospital, Newcastle was undertaken. Twenty-nine subjects, mean age 12 years (range 4.3–20.2), completed weighed food records to determine the contribution of fat to the percentage of the recommended energy intake obtained and to document use of pancreatic enzyme replacement therapy.
Diets with a high percentage of energy derived from fat did not guarantee that individuals with CF met their energy requirements. Subjects with total fat intakes of 100 g per day or greater, however, achieved in excess of 110% recommended daily intake (RDI) for energy. Up to 47% of subjects consumed more pancreatic enzyme replacement capsules than shown to give maximum effectiveness.
Setting a 100 g daily fat target is a realistic way of ensuring high energy intakes in CF. Fat ready reckoners would identify the fat content of food and prescribe specific numbers of pancreatic enzyme replacement capsules to be consumed with each meal or food item. 相似文献
Methodology:
A cross-sectional measurement of clinical characteristics and energy and fat intakes in patients attending the CF outpatients clinic of the John Hunter Hospital, Newcastle was undertaken. Twenty-nine subjects, mean age 12 years (range 4.3–20.2), completed weighed food records to determine the contribution of fat to the percentage of the recommended energy intake obtained and to document use of pancreatic enzyme replacement therapy.
Results:
Diets with a high percentage of energy derived from fat did not guarantee that individuals with CF met their energy requirements. Subjects with total fat intakes of 100 g per day or greater, however, achieved in excess of 110% recommended daily intake (RDI) for energy. Up to 47% of subjects consumed more pancreatic enzyme replacement capsules than shown to give maximum effectiveness.
Conclusion:
Setting a 100 g daily fat target is a realistic way of ensuring high energy intakes in CF. Fat ready reckoners would identify the fat content of food and prescribe specific numbers of pancreatic enzyme replacement capsules to be consumed with each meal or food item. 相似文献
54.
A patient acceptability study was conducted using patient-controlled intranasal diamorphine. Patients undergoing nonemergency orthopaedic or gynaecological surgery self-administered intranasal diamorphine for 24 h postoperatively. Pain, pain relief, sedation, respiratory rate, nausea and vomiting were assessed regularly. After 24 h, patients and their attending nurses completed a questionnaire assessing satisfaction and practical aspects of the technique. Satisfaction was reported as good or complete by 69% of patients and 69% of nurses. Pain relief was assessed as better than expected by 45% of patients and better than normal by 50% of nurses. Seventy-nine per cent of patients would be pleased to use patient-controlled intranasal diamorphine again and 89% of nurses would be happy for their patients to use it again. Sedation was uncommon and mild and there were no episodes of significant respiratory depression. Fifty-three per cent of patients reported no nausea and 74% did not vomit at any stage. There were seven withdrawals, four due to problems with the device and three due to therapeutic problems. The nasal spray may need modification to improve reliability. However, we found patient-controlled intranasal analgesia an effective technique, which was well tolerated by patients and nurses and was without unpleasant side-effects. Further work to determine how it performs compared with intramuscular or intravenous analgesia is now needed. 相似文献
55.
R Hallett 《Preventive medicine》1986,15(3):213-231
Growing interest has been expressed by the business community concerning intervention against smoking in the workplace. As most adult smokers are unlikely to have access to smokers' clinics or other treatment facilities outside the workplace, the workplace itself could be an ideal location for the provision of treatment programs. If the interest of the business community can be translated into action, large populations of smokers would become accessible to workplace treatment programs. Despite this possibility, the potential of the workplace for smoking intervention remains largely unexplored. In this review, the main reasons for workplace smoking intervention are discussed, and the available evidence for the main strategies (prohibition, incentives, treatment, and multicomponent) is reviewed and critically evaluated. The current emphasis in treatment studies is still on physician counseling, and the quality of reported work uneven. Many published studies not intended as evaluations, and many of those which are, have severe procedural or methodological flaws. The particular problems of evaluating workplace studies are discussed and the current research position is summarized. Because the number of evaluative studies is small, the recommendations that can be based on them are fairly limited. In conclusion, it is argued that a body of well-controlled evaluations is needed before the unique characteristics of the workplace can be assessed and exploited in smoking interventions. 相似文献
56.
57.
58.
Oluwole O. Awosika Marco Sandrini Rita Volochayev Ryan M. Thompson Nathan Fishman Tianxia Wu Mary Kay Floeter Mark Hallett Leonardo G. Cohen 《Brain stimulation》2019,12(3):628-634
Background
Ambulation is an essential aspect of daily living and is often impaired after brain and spinal cord injuries. Despite the implementation of standard neurorehabilitative care, locomotor recovery is often incomplete.Objective
In this randomized, sham-controlled, double-blind, parallel design study, we aimed to determine if anodal transcutaneous spinal direct current stimulation (anodal tsDCS) could improve training effects on locomotion compared to sham (sham tsDCS) in healthy subjects. Methods: 43 participants underwent a single backwards locomotion training (BLT) session on a reverse treadmill with concurrent anodal (n = 22) or sham (n = 21) tsDCS. The primary outcome measure was speed gain measured 24 h post-training. We hypothesized that anodal tsDCS + BLT would improve training effects on backward locomotor speed compared to sham tsDCS + BLT. A subset of participants (n = 31) returned for two additional training days of either anodal (n = 16) or sham (n = 15) tsDCS and underwent (n = 29) H-reflex testing immediately before, immediately after, and 30 min post-training over three consecutive days.Results
A single session of anodal tsDCS + BLT elicited greater speed gain at 24 h relative to sham tsDCS + BLT (p = 0.008, two-sample t-test, adjusted for one interim analysis after the initial 12 subjects). Anodal tsDCS + BLT resulted in higher retention of the acquired skill at day 30 relative to sham tsDCS + BLT (p = 0.002) in the absence of significant group differences in online or offline learning over the three training days (p = 0.467 and p = 0.131). BLT resulted in transient down-regulation of H-reflex amplitude (Hmax/Mmax) in both test groups (p < 0.0001). However, the concurrent application of anodal-tsDCS with BLT elicited a longer lasting effect than sham-tsDCS + BLT (p = 0.050).Conclusion
tsDCS improved locomotor skill acquisition and retention in healthy subjects and prolonged the physiological exercise-mediated downregulation of excitability of the alpha motoneuron pool. These results suggest that this strategy is worth exploring in neurorehabilitation of locomotor function. 相似文献59.
de Haas M; Kerst JM; van der Schoot CE; Calafat J; Hack CE; Nuijens JH; Roos D; van Oers RH; von dem Borne AE 《Blood》1994,84(11):3885-3894
In four healthy volunteers, we analyzed in detail the immediate in vivo effects on circulating neutrophils of subcutaneous administration of 300 micrograms of granulocyte colony-stimulating factor (G-CSF). Neutrophil activation was assessed by measurement of degranulation. Mobilization of secretory vesicles was shown by a decrease in leukocyte alkaline phosphatase content of the circulating neutrophils. Furthermore, shortly postinjection, Fc gamma RIII was found to be upregulated from an intracellular pool that we identified by immunoelectron microscopy as secretory vesicles. Intravascular release of specific granules was shown by increased plasma levels of lactoferrin and by upregulation of the expression of CD66b and CD11b on circulating neutrophils. Moreover, measurement of fourfold elevated plasma levels of elastase, bound to its physiologic inhibitor alpha 1- antitrypsin, indicated mobilization of azurophil granules. However, no expression of CD63, a marker of azurophil granules, was observed on circulating neutrophils. G-CSF--induced mobilization of secretory vesicles and specific granules could be mimicked in whole blood cultures in vitro, in contrast to release of azurophil granules. Therefore, we postulate that the most activated neutrophils leave the circulation, as observed shortly postinjection, and undergo subsequent stimulation in the endothelial microenvironment, resulting in mobilization of azurophil granules. Our data demonstrate that G-CSF should be regarded as a potent immediate activator of neutrophils in vivo. 相似文献
60.
CE Faggons C Mabedi CG Shores S Gopal 《Malawi medical journal : the journal of Medical Association of Malawi》2015,27(3):79-87