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1.
P Kern  J Toy  M Dietrich 《Blut》1985,50(1):1-6
The toxicity of recombinant Interleukin-2 (IL-2) was studied in patients with acquired immunodeficiency syndrome (AIDS) or persistent lymphadenopathy syndrome (LAS). Increasing doses of the drug from 10(3) Units/m2 to 10(6) U/m2 were given as an intravenous bolus injection. At the high-dose levels some minor effects, such as fever up to 39.5 degrees C, chills, malaise or vomiting, were observed. The administration of 10(6) U/m2 as a 4-hour infusion showed identical results. No particular alterations of laboratory parameters were found. At the high-dose level the serum concentration of neopterin, which is released from macrophages after interferon gamma stimulation, was significantly (p less than 0.001) elevated above pretreatment levels. The clinical observation of daily infusions of 10(6)/m2 for 14 days revealed the same side effects. All patients developed lymphocytosis and eosinophilia. Two patients had suffered from severe diarrhoea for several weeks presumably due to cryptosporidiosis. In both cases diarrhoea ceased under the treatment with IL-2 and did not occur in the following two months.  相似文献   
2.
Effects of varied levels of glutathione, an intracellular redox buffer, were examined in the adult male housefly in order to study the inter-relationship between enzymic and non-enzymic antioxidant defenses. An increase of over 100% in the concentrations of glutathione was induced by the administration of 3 mM L-2-oxothiazolidine-4-carboxylate (LOC), which increases the intracellular level of cysteine. A decrease in glutathione concentration of up to 85% was achieved by the administration of L-buthionine-SR-sulfoximine (BUS), which irreversibly inhibits glutamylcysteine synthetase. Life spans of houseflies were shortened by a decrease in the glutathione concentration, but were not prolonged by augmentation of glutathione. Metabolic rate and superoxide dismutase activity were independent of glutathione concentration. H2O2 was increased by both experimental regimes, whereas catalase activity was decreased by BUS. Results suggest that catalase activity is influenced by glutathione concentration.  相似文献   
3.
The seeds of 10 accessions ofLimnanthes, representing 7 species and their varieties were moistened and placed in an 80°F cabinet for up to 14 days. Then they were transferred to 40, 50 or 60°F temperatures for germination. In two accessions, 85% of the seeds became dormant after only 2 days at 80°F. In 6 accessions, up to 80% of the seeds became dormant after 14 days at 80°F. In two other accessions there was little or no dormancy induced. After 16 months, one half the ungerminated seeds in each treatment were dried under room conditions for 2-1/2 months. Then they were again moistened and placed under germination temperatures. Up to 78% of the seeds thus treated germinated, compared with few or none of those maintained continuously under germination conditions.  相似文献   
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5.
Fourteen new naphthalene-based thiosemicarbazone derivatives were designed as anticancer agents against LNCaP human prostate cancer cells and synthesized. MTT assay indicated that compounds 6, 8 and 11 exhibited inhibitory effect on LNCaP cells. Among these compounds, 4-(naphthalen-1-yl)-1-[1-(4-hydroxyphenyl)ethylidene)thiosemicarbazide (6), which caused more than 50% death on LNCaP cells, was chosen for flow cytometric analysis of apoptosis. Flow cytometric analysis pointed out that compound 6 also showed apoptotic effect on LNCaP cells. Compound 6 can be considered as a promising anticancer agent against LNCaP cells owing to its potent cytotoxic activity and apoptotic effect.  相似文献   
6.
We have improved the expression of recombinant human granulocyte-colony-stimulating factor (G-CSF), produced by either pL or trpP expression vectors in Escherichia coli, by altering the sequence at the 5' end of the G-CSF-coding region. Initial attempts to express G-CSF resulted in neither detectable G-CSF mRNA nor protein in the trpP system, and only G-CSF mRNA was detectable in the pL system. We modified both expression vectors to decrease the G + C content of the 5' end of the coding region without altering the predicted amino acid sequence. This resulted in expression of detectable G-CSF mRNA and protein in both systems. Expression reached 17% and 6.5% of the total soluble cellular protein in the pL and trpP expression systems, respectively. The N-terminal sequence of the recombinant G-CSF from the pL system was Met-Thr-Pro-Leu-Gly-Pro-. G-CSF isolated from several human cell lines (including the LD-1 cell line reported here), does not have an N-terminal methionyl residue. Deletion of the threonine codon at the beginning of the coding region for the mature G-CSF resulted in efficient removal of the N-terminal methionine residue during expression in E. coli.  相似文献   
7.
Radical clock substrate probes were used to assess the viability of a discrete substrate radical species in the mechanism of hydrocarbon oxidation by the soluble methane monooxygenase (sMMO) from Methylococcus capsulatus (Bath). New substituted cyclopropane probes were used with very fast ring-opening rate constants and other desirable attributes, such as the ability to discriminate between radical and cationic intermediates. Oxidation of these substrates by a reconstituted sMMO system resulted in no rearranged products, allowing an upper limit of 150 fs to be placed on the lifetime of a putative radical species. This limit strongly suggests that there is no such substrate radical intermediate. The two enantiomers of trans-1-methyl-2-phenyl-cyclopropane were prepared, and the regioselectivity of their oxidation to the corresponding cyclopropylmethanol and cyclopropylphenol products was determined. The results are consistent with selective orientation of the two enantiomeric substrates in the hydrophobic cavity at the active site of sMMO, specific models for which were examined by molecular modeling.  相似文献   
8.
Klur S  Toy K  Williams MP  Certa U 《Genomics》2004,83(3):508-517
Various approaches have been developed for the preparation of samples for gene expression monitoring. For Affymetrix chips, a standard protocol is widely used; however, this is inefficient for small samples such as laser capture microdissections. Several amplification procedures for such samples already exist, and our goal was to test two of them: the first is based on random PCR amplification, and the second, linear amplification, involves performing the standard protocol twice. We analyzed a dilution of a commercially available mouse brain total RNA preparation and microdissections from mouse hippocampus and striatum. We evaluated the quality of microarray data by analyzing several chip parameters and performing multiple comparisons. At the biological level, brain microdissections prepared with either method gave similar expression results. At the technical level, analysis of the commercial sample showed that random PCR amplification is more reproducible, requires smaller RNA input, and generates cRNA of higher quality than linear amplification.  相似文献   
9.
10.
In the present study, some acetamide derivatives were synthesized and their potential analgesic activities were investigated. N-(benzothiazol-2-yl)-2-[(1-substituted-1H-tetrazol-5-yl)thio]acetamide derivatives were obtained by the nucleophilic substitution reaction of 2-chloro-N-(benzothiazole-2-yl)acetamides with appropriate tetrazol-5-thioles. The chemical structures of the compounds were elucidated by IR, 1H-NMR, 13C-NMR and FAB?-MS spectral data and elemental analyses. The prepared compounds were investigated for their potential analgesic properties against thermal, mechanical and chemical nociceptive stimuli using hot-plate, tail-clip and acetic acid-induced writhing tests, respectively. The assessment of motor coordination was carried out using Rota-Rod test. Tested compounds applied at 100 mg/kg doses caused significant decrease in acetic acid-induced writhing responses and increase in hot-plate and tail-clip latencies. None of the compounds exhibited destructive effect on motor coordination of the mice in Rota-Rod performance.  相似文献   
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