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41.
Shin-Ichi Hayama Rika Akamatsu Mayumi Kishimoto Masatsugu Suzuki Hideo Nigi 《Primates; journal of primatology》1988,29(3):423-426
Diverticular disease of the colon was detected in a female Japanese monkey by X-ray examination. The monkey was 15 years old
and had been kept under captive conditions for nine years. Lack of appetite and activity, and constipation were observed.
The monkey was given fiber-rich vegetables and wild plants, and its appetite and activity then improved. Based on a consideration
of various factors, it is suggested that one possible cause of the diverticulosis in this case was a low dietary fiber intake. 相似文献
42.
Specimens ofCanthigaster rivulata (Temminck et Schlegel) were collected from Kominato and Hayama, central Japan, from May, 1985 to October, 1986. On the basis of the gonadosomatic index, gonadal histology and results of artificial fertilization of these specimens, the spawning season is considered to extend from late June to mid-September. The specimens exhibited the following dimorphic differences associated with sex: 1) The male is larger than the female. 2) Ventral side of the body is brownish orange in the male with vermiculated or reticulated patterns of bright violet, while it is white in the female. 3) The male has a well-developed skin fold along the mid-dorsal and mid-ventral lines, which is greatly elevated during courtship; whereas the female’s skin folds are not or slightly developed and conspicuous only during courtship. In an aquarium with the water temperatures of 22 to 26°C, a pair of fish spawned every four days late in the morning for three consecutive months. Courtship and spawning occurred in a pair. The male swam in front of the female, and elevated the skin folds both dorsally and ventrally, fully spreading the unpaired fins, with the ventral side of the body flashing bright blue and the dorsal side turning dark. Both fish swam in a circular fashion, elevating the skin folds. The male followed the female nudging her abdomen with his snout. Both fish turned upward, and released gametes. The eggs are spherical, 0.53–0.73 mm in diameter, demersal, adhesive, transparent, and pale yellowish orange in color, and contain a cross-shaped or asteroid cluster of oil globules. The egg membrane was thick and consisted of about 14 concentric layers. The incubation period ranged from 73.5 hours at 28.2–28.5°C to 145.0 hours at 22.1–22.4°C. The newly hatched larvae were 1.38–1.98 mm in total length (TL) with 84-11-13 = 19–21 myomeres. The yolk was absorbed when the larvae attained 1.49–2.22 mm TL, three days after hatching. The larvae were fed on oyster larvae, blue mussel larvae, sea-urchin larvae and rotifers, but all of them died in 16 days. During the embryonic and early larval stages, the only pigment cells that appeared on the body were the black chromatophores. 相似文献
43.
Summary Neurons containing luteinizing hormone-releasing hormone (LHRH) are first detected in newt embryos (Cynops pyrrhogaster) in the olfactory epithelium and ventromedial portion of the olfactory nerve, after which they sequentially appear in the intracerebral course of the terminal nerve at prometamorphosis, and in the septo-preoptic area at postmetamorphosis. In adults, however, LHRH-immunoreactive cells are rarely seen in the nasal region, and their distribution shifts into the brain, suggesting their migration. In order to ascertain the origin and possible migration route of these neurons in newt larvae, the effect of unilateral or bilateral olfactory placodectomy on the LHRH neuronal system has been studied. Removal of the olfactory placode results in the absence of LHRH-immunoreactive cells in the nasal and brain regions of the operated side, whereas the subsequent growth and the LHRH-immunoreactive cellular distribution in the contralateral side are identical to those of normal larvae. Following bilateral placodectomy, no LHRH immunoreactivity is detected on either side of the olfactory-brain axis. These results suggest that LHRH neurons of the newt, Cynops pyrrhogaster, originate in the olfactory placode and then migrate into the brain during embryonic development. 相似文献
44.
The in vitro activity of several new imidazoles, cloconazole, sulconazole, butoconazole, isoconazole and fenticonazole, were compared with those of amphothericin B, flucytosine, and three azoles: econazole, miconazole and ketoconazole against isolates of pathogenic Candida. A total of 186 clinical isolates of 10 species of the genus Candida and two culture collection strains were tested by an agar-dilution technique. Isoconazole was the most active azole, followed by butoconazole and sulconazole. Differences between some of the species in their susceptibility to the antifungal agents were noted. Sulconazole and cloconazole had the highest activity in vitro against 106 isolates of C. albicans. Butoconazole and isoconazole were also very active against isolates of C. albicans, and were the most active azole compounds against 80 isolates of Candida spp. 相似文献
45.
Homologous pairing is a key step in homologous genetic recombination. In the early stage of trials for the identification of homologous pairing-promoting proteins from a fission yeast, Schizosaccharomyces pombe, we treated DNA products with phenol in the presence of a salt for the removal of tightly bound proteins from DNA before the assay, but we found that this treatment caused very efficient protein-independent double-strand formation from complementary single-stranded DNAs. Using an assay including the phenol treatment, we detected another species of apparent homologous pairing-promoting proteins in the nuclei, in addition to a homologous pairing-promoting protein consisting of three components which we reported previously. However, studies involving the use of an assay without the phenol-treatments revealed that the second one was not really a homologous pairing-protein. Thus, the protein-independent double-strand formation by phenol-treatment in the presence of a salt could cause the erroneous identification of homologous pairing-promoting proteins. 相似文献
46.
T Kato Y Yamagata T Arai E Ichishima 《Bioscience, biotechnology, and biochemistry》1992,56(7):1166-1168
A new extracellular 90-kDa serine proteinase with an isoelectric point (pI) of 3.9 was purified from Bicillus subtilis (natto). Microheterogeneity was detected in the 50-kDa protease of bacillopeptidase F with pI 4.4 reported previously by Wu et al. and the sequence for the first 25 amino acids in the internal region of the enzyme was analyzed: ATDGVEWNVDQIDAPKAWALGYDGA. The cleavage sites in the oxidized B-chain of insulin by the proteinase were CySO3H7-Gly8, Val12-Glu13, Try16-Leu17, and Phe25-Tyr26. The activity was inhibited by phenylmethylsulfonyl fluoride (PMSF) and chymostatin, while the activity was not inhibited by proteinaceous Streptomyces subtilisin inhibitor (SSI) or alpha 2-macroglubulin. 相似文献
47.
Phosphorylation in the carboxyl-terminal domain of the capsid protein of hepatitis B virus: evaluation with a monoclonal antibody. 总被引:1,自引:0,他引:1
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A Machida H Ohnuma F Tsuda A Yoshikawa Y Hoshi T Tanaka S Kishimoto Y Akahane Y Miyakawa M Mayumi 《Journal of virology》1991,65(11):6024-6030
The capsid protein of hepatitis B virus (p21c) is made of 183 amino acids coded for by the C gene. By using p21c isolated from Dane particles (hepatitis B virus) as an immunogen, a monoclonal antibody (no. 2212) which recognized an epitope dependent on the phosphorylation of p21c was raised. The binding of no. 2212 antibody to authentic p21c was completely inhibited by a synthetic undecapeptide with a sequence of RRRSQSPRRRR, representing amino acids 165 to 175 of p21c, only when the peptide was phosphorylated. Either or both of Ser-168 and Ser-170 were phosphorylated in p21c in vivo, therefore, and contributed to the manifestation of the epitope. No. 2212 antibody bound to p21c from core particles derived from Dane particles or hepatocellular carcinoma tissues (PLC/342) propagated in nude mice but did not bind to p21c from core particles expressed in Escherichia coli or yeast cells, indicating different states of phosphorylation in them. Nonphosphorylated p21c showed a higher affinity for the viral DNA than did phosphorylated p21c. Since the serum from an asymptomatic carrier, with a high titer for antibody to hepatitis B core antigen, specifically bound to phosphorylated undecapeptide (amino acids 165 to 175), the epitope would stimulate humoral antibody responses in the human host. 相似文献
48.
Acute pulmonary alveolar hypoxia increases lung and plasma endothelin-1 levels in conscious rats. 总被引:13,自引:0,他引:13
G Shirakami K Nakao Y Saito T Magaribuchi M Jougasaki M Mukoyama H Arai K Hosoda S Suga Y Ogawa 《Life sciences》1991,48(10):969-976
To investigate the effect of pulmonary alveolar hypoxia on the synthesis and release of endothelin (ET)-1, ET-1-like immunoreactivity (-LI) levels of the lung and plasma were measured in conscious unrestrained rats under hypoxic conditions. Sixty-min exposure to alveolar hypoxia (10% O2 or 5% O2) increased the ET-1-LI level in the lung. The plasma ET-1-LI level in hypoxic rats also increased significantly. The increase of plasma and lung ET-1-LI levels were parallel to the severity of hypoxia. These results demonstrates that acute pulmonary alveolar hypoxia increases lung and plasma ET-1-LI levels in conscious unrestrained rats, suggesting a possible physiological or pathophysiological significance of ET in alveolar hypoxia. 相似文献
49.
Yasushi Oda Haruki Nakamura Toshio Yamazaki Kuniaki Nagayama Mayumi Yoshida Shigenori Kanaya Morio Ikehara 《Journal of biomolecular NMR》1992,2(2):137-147
Summary Two-dimensional (2D)1H NMR experiments using deuterium labeling have been carried out to investigate the solution structure of ribonuclease HI (RNase HI) fromEscherichia coli (E. coli), which consists of 155 amino acids. To simplify the1H NMR spectra, two fully deuterated enzymes bearing several prototed amino acids were prepared from an RNase HI overproducing strain ofE. coli grown in an almost fully deuterated medium. One enzyme was selectively labeled by protonated His, He. Val. and Leu. The other was labeled by only protonated His and Ile. The 2D1H NMR spectra of these deuterated R Nase H1 proteins, selectively labeled with protonated amino acids, were much more simple than those of the normally protonated enzyme. The simplified spectra allowed unambiguous assignments of the resonance peaks and connectivities in COSY and NOESY for the side-chain protons. The spin-lattice relaxation times of the side-chain protons of the buried His residue of the deuterated enzyme became remarkably longer than that of the protonated enzyme. In contrast, the relaxation times of the side-chain protons of exposed His residues remained essentially unchanged. 相似文献
50.
Mammalian cell expression cloning has become a standard technique for the isolation of mammalian genes or cDNAs. Its advantage is that the biological functions of the gene of interest are used for cloning. Therefore, the identified cDNAs or genes should be functional in vivo, and there is no need for physical or chemical information about the gene products, so that protein purification in sufficient quantity to raise antibodies or to obtain amino acid sequences is not necessary. Here, we summarize recent progress in mammalian cell cloning systems, and discuss the possible directions in which this technique will lead. 相似文献