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991.
Summary On each lateral side of the cephalothorax segments, the adult Sinelobus stanfordi has a branchial chamber which contains an elongated bag-shaped gill and is covered by a thick branchiostegite. The ultrastructural study revealed that the inner surface of the branchiostegite is composed of a transporting-type epithelium which is morphologically distinct from the gill epithelium. Both epithelia are covered by extremely thin (about 80 nm) cuticle layers, suggesting high permeability to gases, ions, and water. In contrast, the outer surface of the branchiostegite consists of ordinary epithelium covered by a very thick cuticle layer in common with the body surface. The inner branchiostegal epithelium (4–10 m thick) has a shallow (about 1 m deep) apical infolding system of the cell membrane (AIS) and an extensive three-dimensional tubular network (about 120 nm in diameter) which is formed by the invagination of the basolateral cell membrane (TNB). The TNB is associated with slender mitochondria and occupies the majority of the cytoplasmic area of the epithelial cell. The gill epithelium, on the other hand, is about 10 m thick and characterized by an abundance of oval mitochondria, well-developed (4–5 m deep) AIS, and a smooth basal cell membrane lacking any infoldings. These morphological features indicate that not only the gill epithelia, but also the inner branchiostegal epithelia, are involved in the ion-transporting processes. The ultrastructural differences between these two kinds of epithelia also suggest their different roles in the osmoregulation of this animal, since it inhabits estuaries which are subject to extreme changes in salinity. 相似文献
992.
Shigeru Arimori Hideo Terada Kazuo Hayami Yoshitaka Aoyagi Shigeki Motomura Hitoshi Fukawa Noriko Akatsuka Susumu Shimizu Fumio Kodama Shozou Chiba Akio Urabe Mitsuhiro Omine Keiichi Harada 《Biotherapy》1993,6(2):149-153
Under the control of Kanagawa CML/HLBI phase IV study group in Japan, 18 cases out of registered 30 cases of chronic myelogeneous leukaemia consisting of 17 chronic phase and 1 accelerated phase, during July, 1991 to January, 1992, were analyzed for their hematological responses and cytogentic responses preliminarily. Hematological response rate (PR + CR) was 83.3% including 50.0% of CR, as judged by Kimura's criteria after treatment with HLBI alone (16 cases) or/and with other chemotherapy (2 cases). The dosage and duration of HLBI therapy required to get into the complete remission ranged from 212 to 1272 millions IU and between 6 to 42 weeks (mean value was 20 weeks), respectively. The clonally proliferated leukocytes and decreased physiological hematopoiesis started to recover from 2 to 4 weeks and reached their normal ranges from 16 weeks after 6 millions IU of HLBI were administered every day. In the 4 cases examined, 3 cases showed minimal cytogenetic responses and a case showed no cytogenetic response. Slight and temporary adverse effects were observed in 15 out of 18 cases (83.3%) including fever, general malaise, appetite loss, eruption, diarrhea, glossitis, hypogustation, weight loss and local muscle pain.Abbreviations HLBI
Human interferon alpha originated from human lymphoblastoid cell line 相似文献
993.
Jiacong Chen Susumu Shimura Kohtaro Kirimura Shoji Usami 《Applied microbiology and biotechnology》1993,38(6):714-718
Lipase high-producing mutants with petroleum products as carbon sources were successfully induced from Trichosporon fermentans WU-C12 by ultraviolet (UV) light irradiation. In the first mutation step, one mutant strain, PU-30, derived from strain WU-C12 was selected. The productivity of extracellular lipase of PU-30 reached 58 units (U)/ml in the medium containing kerosene, being approximately twice the productivity of the parental strain WU-C12. In the second mutation step, the mutant strain 2PU-18 was induced from strain PU-30. In medium containing kerosene, gas oil and liquid paraffin, the 2PU-18 produced 70 U/ml, 62 U/ml and 60 U/ml of extracellular lipase, respectively. When various n-alkanes (C8-C18) were used as carbon sources, the parental strain WU-C12 produced more than 20 U/ml of lipase only from C9-C12 alkanes, but 2PU-18 could produce more than 50 U/ml of lipase from C8-C18 alkanes. When cultivated for 3 days in medium containing liquid paraffin, the activity ratios of extracellular lipase to total lipase and the values of extracellular lipase activity per dry-cell weight were 0.44 and 0.65 U/mg for WU-C12, and 0.62 and 1.82 U/mg for 2PU-18, respectively. These results indicate that the mutant strain 2PU-18 is superior in both total lipase productivity and permeability of lipase to the parental strain WU-C12 when petroleum products are used as carbon sources.
Correspondence to: S. Usami 相似文献
994.
Summary In the first report in this series we presented dendrograms based on 152 individual proteins of the EF-hand family. In the
second we used sequences from 228 proteins, containing 835 domains, and showed that eight of the 29 subfamilies are congruent
and that the EF-hand domains of the remaining 21 subfamilies have diverse evolutionary histories.
In this study we have computed dendrograms within and among the EF-hand subfamilies using the encoding DNA sequences. In most
instances the dendrograms based on protein and on DNA sequences are very similar. Significant differences between protein
and DNA trees for calmodulin remain unexplained.
In our fourth report we evaluate the sequences and the distribution of introns within the EF-hand family and conclude that
exon shuffling did not play a significant role in its evolution. 相似文献
995.
Manahu Nakajima Qaiser I. Sheikh Kazuyoshi Yamaoka Yoshiyasu Yui Susumu Kajiwara Kazuo Shishido 《Molecular & general genetics : MGG》1993,237(1-2):1-9
Summary Previous studies have indicated that DNA bending is a general structural feature of sequences (ARSs) from cellular DNAs of yeasts and nuclear and mitochondrial genomic DNAs of other eukaryotes that are capable of autonomous replication in Saccharomyces cerevisiae. Here we showed that bending activity is also tightly associated with S. cerevisiae ARS function of segments cloned from mitochondrial linear DNA plasmids of the basidiomycetes Pleurotus ostreatus and Lentinus edodes. Two plasmids, designated pLPO2-like (9.4 kb), and pLPO3 (6.6 kb) were isolated from a strain of P. ostreatus. A 1029 by fragment with high-level ARS activity was cloned from pLPO3 and it contained one ARS consensus sequence (A/T)TTTAT(A/G)TTT(A/T) indispensable for activity and seven dispersed ARS consensus-like (10/11 match) sequences. A discrete bent DNA region was found to lie around 500 by upstream from the ARS consensus sequence (T-rich strand). Removal of the bent DNA region impaired ARS function. DNA bending was also implicated in the ARS function associated with a 1430 by fragment containing three consecutive ARS consensus sequences which had been cloned from the L. edodes plasmid pLLE1 (11.0 kb): the three consecutive ARSs responsible for high-level ARS function occurred in, and immediately adjacent to, a bent DNA region. A clear difference exists between the two plasmid-derived ARS fragments with respect to the distance between the bent DNA region and the ARS consensus sequence(s). 相似文献
996.
Masao Yamamoto Yukiko Takayanagi Susumu Nihashi Yutaka Nomura Hiroyuki Nohira 《Chirality》1995,7(8):572-574
Synthesis of (?)-bevantolol hydrochloride from 3,4-dimethoxyphenethylamine and (S)-(+)-m-tolyl glycidyl ether derived from (R)-(?)-epichlorohydrin established the absolute configuration of the (+) and (?) enantiomer as R and S, respectively. The purity of the enantiomers was determines using a chiral cellulose column (CHIRALCEL OD®) which allowed direct separation of the enantiomers. A separation factor (α) of 4.20 and a resolution factor (Rs) of 9.21 were obtained. © 1995 Wiley-Liss, Inc. 相似文献
997.
Fumitoshi Irie Hitomi Murakoshi Takashi Suzuki Yasuo Suzuki Kazuo Kon Susumu Ando Kunihiro Yoshida Yoshio Hirabayashi 《Glycoconjugate journal》1995,12(3):290-297
We previously reported for the first time two Japanese patients with aspartylglycosaminuria (AGU). A novel disialo Asn N-glycoside (AG-5) has been isolated from the urine of one of the patients in addition to four known monosialo Asn N-glycosides (AG-1 to AG-4) by gel filtration and anion exchange chromatography in this study. Final purification of AG-5 was achieved by an electrochemical chromatographic method, high performance liquid chromatography with pulsed amperometric detector (HPLC-PAD). The yield of AG-5 was approximately 1 mg l–1 urine. The chemical structures of AG-1 to AG-5 were characterized by gas-liquid chromatography, a permethylation study, fast atom bombardment-mass spectrometry (FAB-MS), and nuclear magnetic resonance (NMR). Based on the structural analysis, AG-5 had the following novel structure: NeuAc2 8NeuAc2 3Gal1 4GlCNAc1 Asn. 相似文献
998.
Hiroko Takahashi Susumu Suzuki Masayoshi Yamaguchi 《Molecular and cellular biochemistry》1995,142(1):1-7
The effect of hormonal signaling factors on (Ca2+–Mg2+)-ATPase activity in rat liver plasma membranes was investigated. The presence of inositol-glycan (10–7–10–5M), dibutyryl cAMP (10–4 and 10–3M) or inositol 1,4,5-trisphosphate (IP3; 10–6 and 10–5 M) in the enzyme reaction mixture produced a significant increase in (Ca2+–Mg2+)-ATPase activity. These effects were completely inhibited by the presence of vanadate (10–4 M), an inhibitor of the enzyme phosphorylation, and N-ethylmaleimide (5×10–3 M), a SH group modifying reagent. Meanwhile, regucalcin, a Ca2+-binding protein isolated from rat liver cytosol, increased the enzyme activity by binding to the SH groups of (Ca2+–Mg2+)-ATPase in liver plasma membranes. The presence of regucalcin (0.25 M) with an effective concentration completely inhibited the effect of inositol-glycan (10–5 M) to increase (Ca2+–Mg2+)-ATPase activity, while the effect of dibutyryl cAMP (10–3M) or IP3 (10–5M) was not altered. The inositol-glycan effect was not modulated by the presence of dibutyryl cAMP or IP3. Now, the preincubation of the plasma membranes with regucalcin did not modify the effect of inositol-glycan on the enzyme activity, suggesting that regucalcin competes with inositol-glycan for the binding to the plasma membranes. The present results suggest that there may be a cross talk with regucalcin and hormonal signaling factors in the regulation of (Ca2+–Mg2+)-ATPase activity in liver plasma membranes. 相似文献
999.
An UDPG: cyanidin 3-O-glucosyltransferase was isolated and purified about 260-fold from the flower buds ofSenecio x hybridus. The enzyme showed a pH optimum of 7.5 and no additional cofactors were required. The Km values for cyanidin and UDPG were
0.33 and 0.20 mM, respectively. Its molecular mass estimated by Sephacryl S-200 chromatography was 52 kDa. 相似文献
1000.
本实验利用Solt-Farber顺序诱发大鼠肝癌,观察肝组织中GST活性及GST-P含量在化学诱癌中的变化,并观察性激素对大鼠化学诱发肝癌的早期病变中GST-P表达的作用。结果显示无论是GST活性或GST-P的含量,在诱癌至第三周开始升高,第五周升至最高。利用此模式,选择诱癌至第五周,免疫组化法检测各种处理后肝组织中GST-P的表达。发现睾丸假切除的雄性大鼠经化学诱癌后,肝中有高的GST-P表达,睾丸假切除的雄性大鼠诱癌合并雌二醇处理,明显降低肝组织GST-P阳性灶的面积和数量;合并睾丸酮处理,虽减少GST-P阳性灶的面积,但其数量略有升高。与睾丸假切除后诱癌的雄性大鼠相比,切除睾丸的大鼠经诱癌,有更低的GST-P阳性灶的面积;睾丸切除合并雌二醇处理,GST-P阳性灶的面积进一步降低。与仅化学诱癌的卵巢假切除雌性大鼠比,卵巢切除鼠诱癌后,GST-P阳性灶的面积稍有增加;对卵巢切除合用睾丸酮的大鼠诱癌,阳性灶的面积进一部增加。无论性腺切除与否,雄性大鼠比雌性大鼠有更高的GST-P表达。这些结果提示雌激素可抑制而雄激素则可促进化学诱癌大鼠肝中GST-P的表达。这一结果可能与临床上男性较女性易患肝癌有关。 相似文献