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551.
Polyarteritis nodosa (PN), characterized by vasculitis of medium and small sized arteries, is uncommon in children. This disease is thought to be concerned with some abnormal immune responses. Platonin (4,4'-dimethyl-3,3'-di-n-heptyl-8-[2-(4-methyl-3-n-heptylthiazole) ]-2,2'- dicarbocyanine diiodine) is one of the photosensitive dyes of trithiazole pentamethine cyanine. It has been reported that platonin stimulated suppressor/cytotoxic T cells, but suppressed B cells. In clinical observations, platonin is shown to be efficacious for rheumatoid arthritis and juvenile rheumatoid arthritis. In this study, a Japanese boy (9-year-old) with PN was given platonin in combination with prednisolone. Prednisolone was gradually tapered under a cover of platonin. As a result, the relapse has not been exhibited for a long time (72 months). There were no adverse side effects during long term administration of medication.  相似文献   
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553.
The metabolism of a lignin substructure model compound, 1,2-bis(3-methoxy-4-ethoxyphenyl)propane-1,3-diol (Ia) in ligninolytic cultures of Phanerochaete chrysosporium was studied to help elucidate the biochemical mechanism of lignin degradation. The primary reaction was cleavage of the model compound between C1 and C2 of the propane moiety to produce 1-(3-methoxy-4-ethoxyphenyl)ethane-1,2-diol and a C6-C1 product (probably 3-methoxy-4-ethoxybenzaldehyde). Other identified products arose secondarily; all were further metabolized. Even though the model compound was a mixture of four stereoisomers, no stereoselectivity was observed in its metabolism. In cultures under 18O2, the initial cleavage produced the diol product with ≈70% enrichment by 18O in the benzyl alcohol group. The diol was a mixture of the two possible enantiomers, and the O2-derived hydroxyl was incorporated at the asymmetric (benzyl) carbon. (Limited optical activity in the diol was traced to selective further metabolism of the D form.) These results show that the primary cleavage reaction lacked stereospecificity and was primarily oxygenative, implicating a nonspecific oxygenase or a nonenzymatic reaction involving activated oxygen. Preliminary experiments demonstrated no cell homogenate activity against Ia.  相似文献   
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555.
Chronic blockade of cholinergic transmission with atropine resulted in a decrease in atropine-induced activity in the rats, whereas apomorphine - induced locomotion was enhanced. Maximal binding of 3H-quinuclidinyl benzilate (QNB), a muscarinic antagonist, to homogenate of cerebral cortex, striatum and hippocampus was significantly higher in chronic atropine-treated rats than in control animals. No difference was observed in KD value of the specific 3H-QNB binding or in ID50 value of oxotremorine in inhibiting 3H-QNB binding. No change in the specific binding of 3H-spiroperidol, a dopaminergic antagonist, was observed in those three regions of brains of chronic atropine-treated rats when it was compared with that of control animals. The role of brain muscarinic acetylcholine receptors in behavioral responses is discussed relating an effect of dopaminergic neurons on cholinergic activities.  相似文献   
556.
The mode of inheritance of four different red cell antigens (Ecy, Fcy, Gcy, and Hcy), detected by alloimmune reagents prepared by us for the cynomolgus monkey, was studied. The results of the segregation analysis suggest that each antigen is inherited in an autosomal dominant manner. Both the random sample analysis and family study revealed that two of these red cell antigens (Ecy and Fcy) probably represent the products of two independent genes while the expression of the other two antigens (Gcy and Hcy is governed by two autosomal codominant alleles. Thus, three simian-type blood group systems could be demonstrated by the four newly developed alloimmune reagents. We use the following nomenclature for these blood groups: the E and F blood groups, each with two phenotypes, antigen positive (E and F) and antigen negative (e and f), and the GH blood group having three phenotypes (G, H, and GH).  相似文献   
557.
Ovarian luteinizing hormone (LH) receptors were characterized using ovarian tissues from 17 cynomolgus monkeys at different phases of the menstrual cycle. Low binding affinity receptors for 125I-LH were observed throughout the menstrual cycle. The binding affinity of these receptors for LH (< 12 × 1010 M?1) was approximately the same as that of ovarian LH receptors previously reported in human and nonhuman primates. In addition, high-affinity receptors (17?85 × 1010 M?1) were also detected at the mid-luteal phase, during which a large functional corpus luteum was present. Thus the high-affinity LH receptors appear with the formation of the corpus luteum and disappear with its regression. Almost no fluctuation of binding capacity was observed throughout the menstrual cycle (32?112 fmol/ mg of ovarian tissue). The high-affinity LH receptor was judged to be derived from the functional corpus luteum.  相似文献   
558.
The possible involvement of singlet oxygen (1O2) in the degradation of lignin by Phanerochaetechrysosporium was examined. Ligninolytic cultures and photochemically generated 1O2 gave the same oxidation products from the lignin substructure model compound 1,2-bis(3-methoxy-4-alkoxyphenyl)propan-1,3-diol. Fluorescence and near UV absorbance of the specific 1O2 trapping agent anthracene-9,10-bisethanesulfonic acid (AES) disappeared in ligninolytic cultures, indicating that 1O2 was produced. AES strongly inhibited oxidation of 14C-lignin, but not 14C-glucose, to 14CO2 in cultures, and also strongly suppressed oxidation of the model compound. These results indicate the 1O2 plays an integral role in lignin biodegradation.  相似文献   
559.
Restriction fragment length polymorphism in the mitochondrial DNA ofMacaca fascicularis from four geographical regions, Indonesia, the Philippines, Malaysia, and Indochina, was analyzed. In total, 21 types of mitochondrial DNA were detected using five restriction enzymes. These types were divided into two main groups based on phylogenetic analyses, one of which corresponded to the types of continental (Malaysia/Indochina) populations and the other to the types of a insular (Philippine) population. The types in the Indonesian population belonged to both groups. In the phylogenetic tree for the four populations, two clusters were constructed, one for the continental populations and the other for the insular ones.  相似文献   
560.
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