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181.
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The intermolecular cross-links have been studied in the uterine insoluble collagen of guinea pig, pig, cow, and human beings with a single given procedure. After NaB3H4 reduction, there are three intermolecular cross-links; namely, dihydroxylysinonorleucine, hydroxylysinonorleucine, and histidinohydroxymerodesmosine. In human uterine collagen samples these reduced cross-links are present in equal amounts. The reduced intermolecular collagen cross-links of uterine leiomyoma are very similar to those of the normal uterine tissue. Dihydroxylysinonorleucine is the principal reduced cross-link in uterine collagen of guinea pig, pig, and cow. Alkaline hydrolysis reveals that dehydrodihydroxylysinonorleucine and dehydrohydroxylysinonorleucine occur in vivo as glycosylated derivatives. 相似文献
183.
Experience gained from the treatment of 41 patients with 42 operations for the relief of Vth nerve pain over the past 5 years is reported. For the selective section of the posterior root of the trigeminal nerve 28 retrolabyrinthine procedures were performed for typical tic douloureux with complete lasting relief in 25; 1 was relieved with the addition of aspirin; and 2 were relieved by Tegratol even though it was ineffective before surgery. There were no deaths and no serious complications. None had facial paralysis or anesthesia dolorosa. The retrolabyrinthine approach to the posterior root of the trigeminal nerve is ideally suited for those patients with refractory tic douloureux or patients with facial pain secondary to other causes such as tumor. Because of its effectiveness and low morbidity, this procedure offers advantages over other surgical techniques. 相似文献
184.
RL Schecter MA Alaoui-Jamali A Woo WE Fahl G Batist 《Canadian Metallurgical Quarterly》1993,53(20):4900-4906
The role of glutathione-S-transferase (GST) in alkylator drug resistance has been studied in MatB rat mammary carcinoma cells. A series of GST transfectant cell lines was established by using an expression vector containing the complementary DNA for the rat GST Yc gene under regulation of the SV40 early region promoter and the antibiotic resistance plasmid pSV2neo. Transfectant cell lines expressing up to 4-fold higher total GST activity than in the parental wild type cell line were identified. Southern blot analysis confirmed a DNA fragment corresponding in size to the transfected GST Yc complementary DNA. Wild type MatB cells contain very low levels of Yc protein, whereas the Yc+ clones showed greatly increased amounts of the Yc subunit. The effect of increased GST Yc activity on the sensitivity of the transfected clones to various cytotoxic agents was assessed by using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide cell survival assay. The clones expressing recombinant GST Yc were more resistant to melphalan (6- to 12-fold), mechlorethamine (10- to 16-fold), and chlorambucil (7- to 30-fold). In late passage populations of the GST Yc+ clones that had been grown over a period of 14 months under continuous selection in G418, GST activity was decreased and it was paralleled by a decrease in Yc protein. These late passage clones with diminished GST Yc content also demonstrate a partial reversion toward the wild type phenotype as determined by cytotoxicity assays using melphalan, mustargen, and chlorambucil. Interstrand DNA cross-links induced by mechlorethamine were significantly lower at 0, 2, and 20 h posttreatment in one of the GST Yc+ clones when compared to wild type MatB cells. These studies indicate that GST Yc overexpression can confer resistance to alkylating agents and that this correlates with inhibition of DNA cross-link formation. 相似文献
185.
High-resolution 31P NMR spectroscopy at 11.7 T was used to examine the influence of medium formulation (medium and serum type, and concentrations of glucose and inositol) on the cellular phosphate metabolism of CX-1 cells, a human colon cancer cell line derived from HT-29 cells. Striking differences in the 31P spectra of harvested CX-1 cells were observed. The largest variation was seen in the phosphocholine and UDP-hexose levels (up to seven-fold changes), with smaller differences in the levels of other phosphate metabolites. The major UDP-hexose species were found to be UDP-N-acetylglucosamine and UDP-N-acetylgalactosamine (ca 2:1 ratio), which have been proposed in the literature to be markers of cell differentiation status. Medium-induced alterations in metabolite levels were much greater than the normal variations seen in CX-1 control samples grown under identical conditions. They even exceeded the characteristic differences observed between different human tumor cell lines grown under one set of culture conditions. The remarkable sensitivity of CX-1 cellular phosphate metabolism to the culture environment has implications for the comparison of in vitro vs in vivo spectra, and for the interpretation of effects due to growth and therapy. 相似文献
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Therapy of HIV infection is changing rapidly as new drugs are introduced. Many patients with HIV infection require anticonvulsants for therapy or prophylaxis of seizures. Antiretroviral drugs, above all protease inhibitors, and anticonvulsants may cause interactions since they are metabolised through common hepatic pathways and may substantially modulate the activity of numerous cytochrome P450 isoenzymes. We describe known interactions between anticonvulsants and antiretroviral drugs and advise on possible combinations. 相似文献
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CA Juttner WE Fibbe J Nemunaitis L Kanz AM Gianni 《Canadian Metallurgical Quarterly》1994,14(5):689-693
An International Consensus Meeting on blood cell transplantation took place in Heemskerk, The Netherlands on 27-29 June 1994. The term 'blood cell transplantation' was preferred to peripheral blood stem cell transplantation. The following issues were addressed: stem cell assessment and ex vivo expansion, techniques for stem cell mobilization, applications of blood cell transplantation, malignant cell contamination and allogeneic blood cell transplantation. 相似文献