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131.
H Hasegawa 《The Journal of parasitology》1990,76(4):470-480
Six species of the family Heligmonellidae (Nematoda: Trichostrongyloidea), including 3 new species, are recorded from rodents of the subfamily Murinae in the Ryukyu Archipelago and Taiwan. Heligmonoides ikeharai n. sp. from Tokudaia osimensis muenninki on Mt. Yonaha, Okinawa Island, is characterized by extremely long spicules and hypertrophied ridges in the prevulval region. Heligmonoides taiwanensis n. sp. from Apodemus draco on Mt. Alishan, Taiwan, is distinguished from other members of the genus in having a markedly asymmetrical bursa and stout bursal rays. Heligmonoides alishanensis n. sp. from Niviventer confucianus on Mt. Alishan differs from the allied forms in lacking hypertrophied ridges at the level of the middle of the spicules and in having longer spicules and a smaller body. Nippostrongylus sp. from N. confucianus on Mt. Alishan resembles Nippostrongylus brasiliensis but is distinguishable in that the externolateral ray is almost the same length as the lateroventral ray in the left lobe, and the fused tips of the spicules are thin and straight. Heligmonoides ryukyensis from Mus caroli and Orientostrongylus tenorai from Bandicota indica are first recorded from Taiwan. Heligmonellid nematodes parasitic in wild rodents in these areas are considered to have been introduced with their hosts from the mainlands of China and Japan through land connections in the Pleistocene. 相似文献
132.
133.
Close linkage of MEN2A with RBP3 locus in Japanese kindreds 总被引:7,自引:0,他引:7
Masayuki Yamamoto Shin-ichiro Takai Tetsuro Miki Kazuyoshi Motomura Makoto Okazaki Isamu Nishisho Hideo Tateishi Akira Miyauchi Tasuku Honjo A. J. Pakstis Takesada Mori 《Human genetics》1989,81(3):287-288
Summary The gene responsible for multiple endocrine neoplasia type 2A (MEN2A) has recently been assigned to the pericentromeric region of chromsome 10 in European Caucasian kindreds by linkage analysis using a DNA marker, interstitial retinol-binding protein 3 (RBP3). We have found tight linkage between the MEN2A and RBP3 loci in Japanese MEN2A kindreds. The maximum lod score is 5.19 at a recombination fraction of 0.00. This result suggests that mutation of a certain gene close to RBP3 is responsible for MEN2A irrespective of ethnic backgrounds. 相似文献
134.
Summary A much higher incidence of alcohol flushing among Orientals in comparison to Caucasians, i.e., >50% vs 5%–10%, has been attributed to racial differences in alcohol-metabolizing enzymes. A large majority of Orientals are atypical in alcohol dehydrogenase-2 locus (ADH
2
), and their livers exhibit significantly higher ADH activity than the livers of most Caucasians. Approximately 50% of Orientals lack the mitochondrial aldehyde dehydrogenase (ALDH2) activity, and elimination of acetaldehyde might be disturbed. We determined by means of hybridization of genomic DNA samples with allele specific oligonucleotide probes, genotypes of the ADH
2
and ALDH
2
loci in Japanese alcohol flushers and nonflushers. We found that all individuals with homozygous atypical ALDH
2
2
/ALDH
2
2
and most of those with heterozygous atypical ALDH
1
2
/ALDH
2
2
were alcohol flushers, while all subjects with homozygous usual ALDH
1
2
/ALDH
1
2
were nonflushers. Frequency of the atypical ADH
2
2
was found to be higher in alcohol flushers than in nonflushers, but the statistical significance was not established in the sample size examined. 相似文献
135.
Ikuo Saiki Hiroaki Maeda Jun Murata Nobuchika Yamamoto Makoto Kiso Akira Hasegawa Ichiro Azuma 《Cancer immunology, immunotherapy : CII》1989,30(3):151-157
Summary We have investigated the effect of endogenous production of tumor necrosis factor (TNF) induced by the combination of recombinant interferon (rIFN) as a primer followed by GLA-60 as a trigger (rIFN/GLA-60) on murine lung metastases caused by B16-BL6 melanoma. In order to examine the therapeutic effect of endogenous TNF on tumor metastasis, the ability of multiple administrations of rIFN/GLA-60 to induce TNF production was also tested. The multiple administrations of rIFN/GLA-60 at intervals of 2 days were effective for the induction of endogenous TNF in mice but continuous multiple administrations of them for 2–4 days were not. In tumor-bearing mice, the production of endogenous TNF by rIFN/GLA-60 was less than that of normal mice, but treatment 3 days after the surgical excision of primary tumors showed the endogenous TNF production to be similar to that in normal mice. In the experimental lung metastasis model, intravenous administration of rIFN followed by intravenous or intranasal administration of GLA-60 showed potent inhibition of lung metastases of B16-BL6 melanoma, whereas the reverse sequence of administration (GLA-60/rIFN) or administration of a mixture of rIFN and GLA-60, which cannot induce the production of TNF, caused no inhibition of lung metastases. These results indicated that the regression of tumor metastases by rIFN/GLA-60 was mediated by the production of endogenous TNF in addition to the direct effects of both immunostimulants. Furthermore, the administration of rIFN and GLA-60 significantly inhibited the tumor metastases in spontaneous lung metastasis model. These results may provide a promising approach for the treatment of cancer metastasis as a result of its ability to induce endogenous TNF. 相似文献
136.
Kuriyama Akira; Takeuchi Masayuki; Ueno Saburo; Mitsuda Hisateru 《Plant & cell physiology》1990,31(7):999-1004
Protoplasts were isolated from subcultured gametophytes of Equisetumarvense by treatment with Driselase and then cultured in vitro.Addition of activated charcoal (AC) to the culture medium enhancedthe rate of cell division, as well as the survival of both protoplastsand regenerated protoplasts. However, subsequent division ofcells was not observed after one or two cycles of replicationin cultures supplemented with AC. When regenerated protoplastswere transferred to fresh medium without AC 3 to 5 weeks afterthe first plating, the transferred cells formed rhizoids anddeveloped into small, young gametophytes without the prior formationof cell clusters or calluses. Furthermore, sprophytic shootsdifferentiated from the protoplast-derived gametophytes whenthey were cultured on medium supplemented with 6-benzylaminopurine(BA). (Received April 5, 1990; Accepted July 30, 1990) 相似文献
137.
Che Fang-Sik; Cho Chol; Hyeon Sung-Be; Isogai Akira; Suzuki Akinori 《Plant & cell physiology》1990,31(1):45-50
The incorporation rate of choline chloride and allylcholinebromide into wheat protoplasts were rapid compared with theincorporation rate of benzylcholine bromide. Choline chloridewas metabolized via two pathways: choline betaine and choline phosphorylcholine phos-phatidylcholine. Allylcholine bromidewas metabolized via only one pathway: allylcholine phosphorylallylcholine phosphatidylallylcholine, and benzylcholine bromide was notmetabolized at all. These results suggest that the stimulationof photosynthesis (Hyeon et al. 1988) by these compounds iscaused directly by these choline analogs and not by their metabolites. (Received June 29, 1989; Accepted October 20, 1989) 相似文献
138.
Nakayama Ishizue; Miyazawa Takeshige; Kobayashi Masatomo; Kamiya Yuji; Abe Hiroshi; Sakurai Akira 《Plant & cell physiology》1990,31(2):195-200
The effects of a novel plant growth regulator (PGR) prohexadionecalcium (BX-112; calcium 3,5-dioxo-4-propionylcyclohexanecarboxylate)on shoot elongation caused by exogenously applied GA1, GA3,GA4) GA19 and GA20 were investigated in rice (Oryza sativa L.cv. Nihonbare and cv. Tan-ginbozu) seedling test. Dependingon the dose, BX-112 reduced shoot elongation in both cultivarscaused by GA19 and GA20, but not by GA1. When a high dose ofBX-112 (e.g. 250 ng/plant and over) was applied with GA1, orGA4, shoot elongation was even promoted. This promotive effect,however, was not observed with GA3. These results suggest thatBX-112 inhibits gibberellin (GA) biosynthesis in the rice plantat the 3ß- and 2ß-hydroxylation of GAs,namely steps of activation and inactivation, respectively. (Received September 6, 1989; Accepted November 27, 1989) 相似文献
139.
Carbon use efficiencies (gram cell organic dry weight accumulated per gram sugar assimilated from the medium) of unadapted and NaCl-adapted (428 millimolar) cells of tobacco (Nicotiana tabacum L. var Wisconsin 38) were determined to evaluate metabolic costs associated with growth and survival in a saline environment. No net increase in carbon costs was associated with salt adaptation. At low substrate levels, carbon use efficiencies of unadapted and NaCl-adapted cells were not appreciably different (0.495 and 0.422, respectively) and at higher substrate levels carbon use efficiency of NaCl-adapted cells was clearly higher than that of unadapted cells. These results indicate that a homeostasis of metabolic efficiency is established after cells have adapted to NaCl. Altered carbon availability does not cause the reduced cell volume that results from adaptation to NaCl. This does not preclude, however, the possibility that altered intracellular partitioning of carbon affects cell expansion. 相似文献
140.
H Hasegawa 《The Journal of parasitology》1989,75(6):863-869
Uncinaria (Uncinaria) maya n. sp. (Nematoda: Ancylostomatidae) and Molineus springsmithi yayeyamanus n. subsp. (Nematoda: Molineidae) are described from the Iriomote cat, Prionailurus iriomotensis, on Iriomote Island, Okinawa, Japan. Uncinaria (U.) maya resembles Uncinaria (Uncinaria) felidis Maplestone, 1939, from Prionailurus bengalensis of India but is distinguished in that the body is much smaller, the ventral rays are set closely with the lateral rays, and the externolateral ray is much shorter than other laterals. Molineus springsmithi yayeyamanus differs from Molineus springsmithi springsmithi Inglis and Ogden, 1965, from Prionailurus bengalensis horsfieldi of East Nepal in that the body is much longer, whereas the esophagus is somewhat shorter and the spicules are divided more distally. Presence of the closely related nematodes in both the Iriomote cat and P. bengalensis suggests a close evolutionary relationship of the 2 hosts. 相似文献