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941.
942.
本文通过试验,探讨了稻谷直接加热烘干过程中,污染的机理、程度。通过数据处理给出了污染与烘干时间,热风增温之间定量关系式,可供研究粮食烘干参考。 相似文献
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946.
DNA mismatch repair and O6-alkylguanine-DNA alkyltransferase analysis and response to Temodal in newly diagnosed malignant glioma 总被引:1,自引:0,他引:1
HS Friedman RE McLendon T Kerby M Dugan SH Bigner AJ Henry DM Ashley J Krischer S Lovell K Rasheed F Marchev AJ Seman I Cokgor J Rich E Stewart OM Colvin JM Provenzale DD Bigner MM Haglund AH Friedman PL Modrich 《Canadian Metallurgical Quarterly》1998,16(12):3851-3857
PURPOSE: We evaluated the response to Temodal (Schering-Plough Research Institute, Kenilworth, NJ) of patients with newly diagnosed malignant glioma, as well as the predictive value of quantifying tumor DNA mismatch repair activity and O6-alkylguanine-DNA alkyltransferase (AGT). PATIENTS AND METHODS: Thirty-three patients with newly diagnosed glioblastoma multiforme (GBM) and five patients with newly diagnosed anaplastic astrocytoma (AA) were treated with Temodal at a starting dose of 200 mg/m2 daily for 5 consecutive days with repeat dosing every 28 days after the first daily dose. Immunochemistry for the detection of the human DNA mismatch repair proteins MSH2 and MLH1 and the DNA repair protein AGT was performed with monoclonal antibodies and characterized with respect to percent positive staining. RESULTS: Of the 33 patients with GBM, complete responses (CRs) occurred in three patients, partial responses (PRs) occurred in 14 patients, stable disease (SD) was seen in four patients, and 12 patients developed progressive disease (PD). Toxicity included infrequent grades 3 and 4 myelosuppression, constipation, nausea, and headache. Thirty tumors showed greater than 60% cells that stained for MSH2 and MLH1, with three CRs, 12 PRs, three SDs, and 12 PDs. Eight tumors showed 60% or less cells that stained with antibodies to MSH2 and/or MLH1, with 3 PRs, 3 SDs, and 2 PDs. Eleven tumors showed 20% or greater cells that stained with an antibody to AGT, with 1 PR, 2 SDs, and 8 PDs. Twenty-five tumors showed less than 20% cells that stained for AGT, with 3 CRs, 12 PRs, 4 SDs, and 6 PDs. CONCLUSION: These results suggest that Temodal has activity against newly diagnosed GBM and AA and warrants continued evaluation of this agent. Furthermore, pretherapy analysis of tumor DNA mismatch repair and, particularly, AGT protein expression may identify patients in whom tumors are resistant to Temodal. 相似文献
947.
HS Lee C Densem RD Levy DH Bennett SG Ray NH Brooks 《Canadian Metallurgical Quarterly》1998,80(5):505-508
The efficacy and toxicity of chronic administration of oral etoposide was evaluated in 61 patients with inoperable non-small-cell lung cancer (NSCLC). Ten patients received previous chemotherapy, 15 received radiotherapy, and one received both treatments. Twenty-four patients had concurrent cardiac and/or pulmonary impairment, which precluded more intensive treatment. Etoposide was given orally, 100 mg daily for 7 consecutive days and consequently 100 mg every other day for 14 more days in a 28-day schedule. Partial response was observed in 17 patients (28%; 95% confidence interval, 17-39%) and stable disease in 21 (34%). The median duration of response was 6 months (range, 2-34 months). The median survival for responders was 22 months and that of nonresponders was 7 months (p < 0.001). The median survival for all patients was 9 months (range, 1-35 months; 95% confidence interval, 5.69-12.31%). Toxicity was acceptable. Other than alopecia, which was observed in all patients, myelotoxicity was the most common toxicity--particularly leukopenia, which was severe in nine patients. Other less common toxicities included nausea and vomiting, stomatitis, anorexia, and neurotoxicity and were mild. No treatment-related deaths were observed. In conclusion, the regimen was effective and well tolerated with significant survival benefit for the responders. It represents an interesting therapeutic approach, especially in the elderly. 相似文献
948.
T Winkler HS Sharma E St?lberg RD Badgaiyan P Alm J Westman 《Canadian Metallurgical Quarterly》1998,14(1-3):131-139
The possibility that nitric oxide is somehow involved in the early bioelectrical disturbances following spinal cord injury in relation to the later pathophysiology of the spinal cord was examined in a rat model of spinal cord trauma. A focal trauma to the rat spinal cord was produced by an incision of the right dorsal horn of the T 10-11 segments under urethane anaesthesia. The spinal cord evoked potentials (SCEP) were recorded using epidural electrodes placed over the T9 and T12 segments of the cord following supramaximal stimulation of the right tibial and sural nerves in the hind leg. Trauma to the spinal cord significantly attenuated the SCEP amplitude (about 60%) immediately after injury which persisted up to 1 h. However, a significant increase in SCEP latency was seen at the end of 5 h after trauma. These spinal cord segments exhibited profound upregulation of neuronal nitric oxide synthase (NOS) immunoreactivity, and the development of edema and cell injury. Pretreatment with a serotonin synthesis inhibitor drug p-chlorophenylalanine (p-CPA) or an anxiolytic drug diazepam significantly attenuated the decrease in SCEP amplitude, upregulation of NOS, edema and cell injury. On the other hand, no significant reduction in SCEP amplitude, NOS immunolabelling, edema or cell changes were seen after injury in rats pretreated with L-NAME. These observations suggest that nitric oxide is somehow involved in the early disturbances of SCEP and contribute to the later pathophysiology of spinal cord injury. 相似文献
949.
HS Singer JD Giuliano BH Hansen JJ Hallett JP Laurino M Benson LS Kiessling 《Canadian Metallurgical Quarterly》1998,50(6):1618-1624
BACKGROUND: Similar to the model for Sydenham's chorea, antineuronal antibodies, which develop in response to a preceding streptococcal infection, have been speculated to have a role in the development of Tourette syndrome (TS). METHODS: Serum antibodies against human caudate, putamen, and globus pallidus (interna and externa) were assayed by enzyme-linked immunosorbent assay (ELISA) and Western blot techniques and results were correlated with clinical characteristics and markers of streptococcal infection. SUBJECTS: A total of 41 children with TS (mean age, 11.3 years) and 39 controls (mean age, 12.1 years) were included. RESULTS: Compared with controls, TS subjects had a significant increase in the mean (p=0.006) and median (p=0.002) ELISA optical density (OD) levels of serum antibodies against putamen, but not caudate or globus pallidus. Western blots on 20 control and 20 TS serum samples showed that specific antibodies to caudate/putamen occurred more frequently in TS subjects at 83, 67, and 60 kDa; antigens were present in a synaptosomal fraction. TS subjects with a positive family history of tics had higher OD values (p < or = 0.04), but no association was shown with age of tic onset, tic severity, sudden onset of tics, or presence of attention-deficit hyperactivity disorder or obsessive-compulsive disorder. Risk ratio calculations in TS and control groups and in study subjects dichotomized for high and low putamen OD values were similar for titers of antistreptolysin O > or = 166 or antideoxyribonuclease B > or = 170. A subgroup analysis limited to subjects with elevated streptococcal titers, however, showed a significantly (p < or = 0.004) larger number of TS subjects with elevated OD levels. CONCLUSION: Children and adolescents with TS had significantly higher serum levels of antineuronal antibodies against putamen than did controls, but their relation to clinical characteristics and markers for streptococcal infection remains equivocal. 相似文献
950.
The effects of berberine, an isoquinoline alkaloid, were investigated in human myeloma cells. In cells with intracellular Ca2+ concentration ([Ca2+]i) = 10 nM, the depolarizing square pulses from -80 mV elicited an instantaneous outward current with an inactivation. This outward current was voltage dependent, activating at -30 mV and showed inactivation with repetitive depolarization, and was hence believed to be n type voltage-activated K+ current (IK(V)). Berberine (30 microM) produced a prolongation in the recovery of IK(V) inactivation. In cells with [Ca2+]i = 1 microM, berberine also inhibited A23187-induced IK(Ca). Berberine (1-300 microM) caused the inhibition of IK(V) and IK(Ca) in the concentration-dependent manners. The IC50 values of berberine-induced inhibition of IK(V) and IK(Ca) were approximately 15 microM and 50 microM, respectively. In inside-out configurations, berberine inside the pipette suppressed the activity of K(Ca) channels without changing the single channel conductance. Berberine also inhibited the proliferation of this cell line and the IC50 value of berberine-induced inhibition of cell proliferation was 5 microM. Thus, the cytotoxic effect of berberine in cancer cells may be partially explained by its direct blockade of these K+ channels. 相似文献