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81.
Weisdorf DJ; Verfaillie CM; Davies SM; Filipovich AH; Wagner JE Jr; Miller JS; Burroughs J; Ramsay NK; Kersey JH; McGlave PB 《Blood》1995,85(12):3452-3456
Delay in hematologic recovery after bone marrow transplantation (BMT) can extend and amplify the risks of infection and hemorrhage, compromise patients' survival, and increase the duration and cost of hospitalization. Because current studies suggest that granulocyte- macrophage (GM) colony-stimulating factor (CSF) may potentiate the sensitivity of hematopoietic progenitor cells to G-CSF, we performed a prospective, randomized trial comparing GM-CSF (250 micrograms/m2/d x 14 days) versus sequential GM-CSF x 7 days followed by G-CSF (5 micrograms/kg/d x 7 days) as treatment for primary or secondary graft failure after BMT. Eligibility criteria included failure to achieve a white blood cell (WBC) count > or = 100/microL by day +21 or > or = 300/microL by day +28, no absolute neutrophil count (ANC) > or = 200/microL by day +28, or secondary sustained neutropenia after initial engraftment. Forty-seven patients were enrolled: 23 received GM-CSF (10 unrelated, 8 related allogeneic, and 5 autologous), and 24 received GM- CSF followed by G-CSF (12 unrelated, 7 related allogeneic, and 5 autologous). For patients receiving GM-CSF alone, neutrophil recovery (ANC > or = 500/microL) occurred between 2 and 61 days (median, 8 days) after therapy, while those receiving GM-CSF+G-CSF recovered at a similar rate of 1 to 36 days (median, 6 days; P = .39). Recovery to red blood cell (RBC) transfusion independence was slow, occurring 6 to 250 days (median, 35 days) after enrollment with no significant difference between the two treatment groups (GM-CSF: median, 30 days; GM-CSF+G- CSF; median, 42 days; P = .24). Similarly, platelet transfusion independence was delayed until 4 to 249 days (median, 32 days) after enrollment, with no difference between the two treatment groups (GM- CSF: median, 28 days; GM-CSF+G-CSF: median, 42 days; P = .38). Recovery times were not different between patients with unrelated donors and those with related donors or autologous transplant recipients. Survival at 100 days after enrollment was superior after treatment with GM-CSF alone. Only 1 of 23 patients treated with GM-CSF died versus 7 of 24 treated with GM-CSF+G-CSF who died 16 to 84 days (median, 38 days) after enrollment, yielding Kaplan-Meier 100-day survival estimates of 96% +/- 8% for GM-CSF versus 71% +/- 18% for GM-CSF+G-CSF (P = .026). These data suggest that sequential growth factor therapy with GM-CSF followed by G-CSF offers no advantage over GM-CSF alone in accelerating trilineage hematopoiesis or preventing lethal complications in patients with poor graft function after BMT.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
82.
幽门螺杆菌cagⅡ对胃上皮细胞IL-8基因转录的影响及机制 总被引:6,自引:0,他引:6
目的探讨HpcagⅡ对胃上皮细胞IL-8基因转录的影响及信号传导机制。方法构建
cagⅡ基因位点缺失Hp突变株及带有IL-8报告基因的人胃癌细胞系L5F11,用液体闪烁计数仪测定荧光素酶(IL8转录)活性,用ELISA法测定IL8蛋白浓度。结果所有Hp突变株诱导荧光素酶活性与IL8蛋白浓度较亲代菌株26695均降低[(0.13±0.01)×cpm比(0.59±0.05)×(P<0.01);(0.73±0.13)ng/ml比(2.22±0.65)ng/ml,(P<0.05)]。PTK抑制剂herbimycinA不仅抑制Hp诱导的荧光素酶活性[(0.71±0.18)×cpm比(1.51±0.23)×cpm,(P<0.05)],而且抑制IL-8蛋白表达[(0.83±0.41)ng/ml比(3.22±0.59)ng/ml,(P<0.05)],但herbimycinA对TNFα诱导的荧光素酶活性及IL8蛋白表达均无影响(P均>0.05);PKA抑制剂H7抑制TNFα诱导的荧光素酶活性[(0.74±0.16)×cpm比(2.62±0.26)×cpm,(P<0.001)]及IL8蛋白表达[(1.45±0.38)ng/ml比(4.12±0.43)ng/ml,(P<0.01)],而对Hp诱导的荧光素酶活性无影响(P>0.05)。结论HpcagⅡ中的多基因能够调节胃上皮细胞IL-8基因转录,且这一作用主要经蛋白酪氨酸激酶途径。 相似文献
83.
84.
BACKGROUND: Patients who present with fulminant hepatic failure due to Wilson's disease may develop hemolytic anemia and renal insufficiency. In this entity, acute hepatocellular necrosis triggers the release of copper ions into the circulation, which leads to toxic effects on red cell metabolic pathways and hemolysis. STUDY DESIGN AND METHODS: The utility of therapeutic plasma exchange to rapidly remove copper and reduce toxic serum copper levels was studied in two patients with fulminant Wilson's disease. RESULTS: Intensive plasma exchange using fresh-frozen plasma replacement removed substantial amounts of copper from the hypercupremic patients, resulting in a rapid reduction in serum copper levels and decreased hemolysis. The net copper removal was proportional to the serum level, ranging from 7,000 to 11,800 micrograms per procedure in one patient and from 3,700 to 6,800 micrograms in the other. CONCLUSION: Plasma exchange allows a rapid reduction in elevated serum copper levels in patients with fulminant Wilson's disease. This leads to an amelioration of hemolytic anemia and provides clinical stabilization until liver transplantation can be performed. 相似文献
85.
Translocation breakpoints are clustered on both chromosome 8 and chromosome 21 in the t(8;21) of acute myeloid leukemia 总被引:3,自引:0,他引:3
The t(8;21)(q22;q22) is consistently associated with acute myeloid leukemia (AML) M2. Recent data have suggested that breakpoints on chromosome 21 are clustered within a single intron of a novel gene, AML1, just downstream of a region of homology to the runt gene of D melanogaster. In this report, we confirm rearrangement at the same location in at least 12 of 18 patients with t(8;21). Furthermore, we have isolated recombinant clones spanning the breakpoint regions on both the der(8) and the der(21) from one patient. By using a chromosome 8 probe derived from these clones, we show that t(8;21) breakpoints are also clustered on chromosome 8. 相似文献
86.
ObjectiveTo determine the knowledge of HIV/AIDS among primary school pupils in north central area of Nigeria.Methods2000 randomly selected primary school pupils in and around eastern part of Idoma area of Benue state were interviewed using an open-ended questionnaire. Data analysis was done with EPI-INFO 2000. The Chi-square test was used for statistical analysis and the 0.05 level of significance was adopted.ResultsA totle of 1010 males and 990 females at ages between five and sixteen years were drawn from 10 primary schools in the area. Pupils in the higher classes were more knowledgeable and sex difference was not statistically significant. Certain misconceptions were noted.ConclusionsThere is need for health education for all cadres of primary school pupils in the area, which will increase the awareness of the disease. 相似文献
87.
88.
89.
Stimulus generalization of fear responses: effects of auditory cortex lesions in a computational model and in rats 总被引:3,自引:2,他引:1
Armony JL; Servan-Schreiber D; Romanski LM; Cohen JD; LeDoux JE 《Cerebral cortex (New York, N.Y. : 1991)》1997,7(2):157-165
The conditioning of fear responses to a simple acoustic stimulus (pure
tone) paired with footshock can be mediated by the transmission of auditory
information to the lateral nucleus of the amygdala from either the auditory
thalamus or the auditory cortex. We examined the processing capacity of the
thalamo-amygdala pathway by making lesions of the auditory cortex and
testing the extent to which conditioned fear responses generalized to tones
other than the one paired with footshock. Two studies were performed, one
in an anatomically constrained computational model of the fear conditioning
network and the other in rats. Stimulus generalization was unaffected in
both. These findings support the validity of the model as an approach to
studying the neural basis of conditioned fear learning, and in addition
suggest that the thalamo-amygdala pathway, possibly by the use of
population coding, is capable of performing at least crude stimulus
discriminations.
相似文献
90.
NP Stocks DipPH FRACGP FAFPHM JE Hiller PhD MPH BA DipSocStuds H Newland FRACS FRACO MPH 《Clinical & experimental ophthalmology》1997,25(2):125-131
Background: Australia is a developed country, However; Aboriginal Australians have rates of blindness comparable to Third World countries. There have been well-funded eye health programs for 15 years in Central Australia. This paper examines if there has been an improvement in visual disability of one traditional group of Aboriginal Australians. Methods: Results from an eye health survey of the Anangu Pitjantjatjara of South Australia in 1990 are presented. These data are compared with results for ‘blindness’ and ‘poor vision’ from a national survey undertaken in 1976. The two surveys were comparable in design, both were cross-sectional population-based prevalence surveys. Prevalence rates were adjusted for the size of the source population. Results: Young rural Aboriginal Australians have good visual acuity. Low vision and blindness (WHO definitions) occur in 19.6% and 10.4% of 60+ year olds, respectively. Women were more likely than men to be blind or have low vision (OR= 1.93; 1.06-3.58). There was a decline in ‘poor vision’ between surveys (OR=2.86; 1.86-4.75) but not in ‘blindness’. Conclusion: Although there has been a reduction in the prevalence of visual disability in rural Aboriginal Australians, improvements in the provision of eye care for the elderly need to occur. 相似文献