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1.
As a part of ecological studies onHaemaphysalis longicornis, the effects of controlled temperatures (12, 15, 20, 25 and 30°C; 100% RH) on development and growth of the tick were investigated and the critical low temperature for each stage in the life cycle was estimated. As the temperature became low, the periods of preoviposition, oviposition, egg hatching (incubation) and moulting were prolonged. At 12°C, however, oviposition, egg hatching and moulting of the larva and nymph did not occur. The critical low temperatures for oviposition, egg hatching (developmental zero) and larval and nymphal moulting which were calculated theoretically from the regression equations, were 11.1, 12.2, 10.2 and 11.8°C, respectively. The temperature also affected the egg productivity and hatch-ratio. The number of deposited eggs per mg of body weight decreased markedly at 15°C, and the hatch-ratio was lowered with dropped temperatures. 相似文献
2.
Immune response to Toxoplasma gondii--analysis of suppressor T cells in a patient with symptomatic acute toxoplasmosis 总被引:1,自引:0,他引:1
A Yano K Norose K Yamashita F Aosai K Sugane K Segawa S Hayashi 《The Journal of parasitology》1987,73(5):954-961
Unresponsiveness of antigen-dependent (Toxoplasma-specific and purified protein derivative of tuberculin [PPD]-specific) T-cell proliferative responses of peripheral blood leukocytes (PBL) was observed in a patient with symptomatic acute toxoplasmosis. The immunosuppression of T-cell responses was mediated by Leu 1+, Leu 2a+, and Leu 3a- suppressor T cells that were induced by Toxoplasma gondii antigen and suppressed both Toxoplasma-specific and PPD-specific PBL T-cell responses from a patient with chronic toxoplasmosis when PBL of these patients were mixed and cocultured in vitro. Participation of class II molecules of HLA in Toxoplasma-specific proliferative T-cell responses and activation of suppressor T cells was examined by using monoclonal antibodies specific for HLA-DR and HLA-DQ molecules. Anti-HLA-DQ monoclonal antibody released the suppressive activity, while anti-HLA-DR monoclonal antibody inhibited Toxoplasma-specific T-cell responses. Thus, the suppressive effect of PBL from a patient with acute toxoplasmosis on antigen-dependent PBL T-cell responses from a patient with chronic toxoplasmosis was mediated by HLA-DQ molecules. By contrast, Toxoplasma-specific T-cell responses were activated by HLA-DR molecules (presumably present on antigen-presenting cells). 相似文献
3.
Y Seino K Tanaka J Takeda H Takahashi T Mitani M Kurono T Kayano G Koh H Fukumoto H Yano 《FEBS letters》1987,223(1):74-76
A cDNA clone encoding the human motilin precursor was isolated from an intestinal library using synthetic oligonucleotide probes. The predicted amino acid sequence indicates that the motilin precursor consists of 115 amino acids and includes a 25-residue N-terminal signal peptide followed by the 22-amino-acid motilin sequence and a long, 68-residue C-terminal peptide. The amino acid sequence of human motilin predicted from the cDNA sequence is identical to its porcine counterpart, which has been determined by protein sequencing. Proteolytic processing of promotilin to motilin occurs at the sequence, Lys-Lys, this being the first reported instance of processing occurring at a pair of Lys residues. In other precursors it occurs at Lys-Arg, Arg-Arg, Arg, or very rarely Lys. 相似文献
4.
Two monomeric 32-kDa proteins, termed 32K-I (pI 5.8) and 32K-II (pI 5.1), were isolated from human placenta, which was solubilized by a Ca2+-chelator. Only 32K-I was associated with PLA2-inhibitory activity. CNBr peptide mapping indicated that 32K-I was distinct from 32K-II and two 36-kDa proteins, called calpactin I and II or lipocortin II and I, which have been shown to possess PLA2-inhibitory activity. 32K-I bound to PS in a Ca2+-dependent manner. 32K-I was detected in many tissues except brain, cardiac and skeletal muscle. 相似文献
5.
Ahmed Landoulsi Patrick Hughes Renee Kern Masamichi Kohiyama 《Molecular & general genetics : MGG》1989,216(2-3):217-223
Summary Plasmid DNA containing the replication origin of the Escherichia coli chromosome (oriC) has been shown to be inefficient as a template for DNA synthesis in vitro when isolated from dam mutants. here, we extend this study to hemimethylated oriC plasmids and to replication in dam-3 mutant enzyme extracts. The results show that: (1) hemimethylated oriC plasmids replicate with the same low efficiency as nonmethylated DNA; (2) DNA synthesis starts at oriC regardless of the methylated state of the template; (3) replication in dam-3 enzyme extracts is inefficient because this strain is deficient in DnaA protein; and (4) consistent with this observation, the copy number of the oriC plasmid pFH271 is reduced in the dam-3 mutant. However, we have found that low DnaA protein levels in dam-3 mutants are not sufficient to explain the reduced transformation efficiency of oriC plasmids. We suggest that there must exist in vivo inhibitory factors not present or present in low quantities in vitro which specifically recognize the hemimethylated or nonmethylated forms of the oric region. 相似文献
6.
Correction of congenital microtia using the tissue expander 总被引:6,自引:0,他引:6
Y Hata K Hosokawa K Yano K Matsuka O Ito 《Plastic and reconstructive surgery》1989,84(5):741-51; discussion 752-3
We attempted auricular reconstruction using Radovan-type inflatable silicone expanders in six children and one adult, with the complete hypoplastic, the conchal remnant, and constricted type of microtia. Ear frameworks, including the helix, anthelix, concha, and tragus, were prepared using autologous rib cartilage. Based on the surface area of the normal adult auricle, the silicone expander was tentatively shaped and sized into a rotated semiellipse and expanded with 70 cc saline. Auricular reconstruction on the framework was completed at the time of insertion in four of the seven patients, requiring no elevation of the ear. The reconstructed auricle was satisfactory in both color and texture and had nearly normal sensation. Mild complications were noted in three of the seven patients. However, no resorption of the inserted rib cartilage has been observed 14 months to 2 years and 5 months after the operation. Slight shrinkage of the expanded skin was noted in each patient. 相似文献
7.
8.
Exon-intron organization, expression, and chromosomal localization of the human motilin gene 总被引:1,自引:0,他引:1
H Yano Y Seino J Fujita Y Yamada N Inagaki J Takeda G I Bell R L Eddy Y S Fan M G Byers 《FEBS letters》1989,249(2):248-252
The human motilin gene has been isolated and characterized. The gene spans about 9 kilobase pairs (kb) and the 0.7 kb motilin mRNA is encoded by five exons. The 22-amino-acid motilin sequence is encoded by exons 2 and 3. The human motilin gene was mapped to the p21.2----p21.3 region of chromosome 6 by hybridization of the cloned cDNA to DNAs from a panel of reduced human-mouse somatic cell hybrids and by in situ hybridization to human prometaphase chromosomes. RNA blotting using RNA prepared from various regions of the human gastrointestinal tract revealed high levels of motilin mRNA in duodenum and lower levels in the antrum of the stomach; motilin mRNA could not be detected by this procedure in the esophagus, cardia of the stomach, descending colon or gallbladder. 相似文献
9.
Heterogeneity of big-big hPRL in hyperprolactinemia 总被引:1,自引:0,他引:1
T Tanaka H Yano S Umezawa Y Shishiba K Okada T Saito I Hibi 《Hormones et métabolisme》1989,21(2):84-88
Sera from a patient with macroprolactinoma (case 1) and from a hyperprolactinemic woman with regular menstruation (case 2) were analyzed for prolactin activity by gel filtration using Sephadex G-100, Sephadex G-200 and TSK G3000SW columns. The chromatographic profile by Sephadex G-100 showed that the percentage of immunoreactive big-big hPRL was 10.7% in case 1 and 64.1% in case 2. On Sephadex G-200 and TSK G3000SW columns, the molecular weight of big-big hPRL was estimated to be more than 500,000 daltons (big-big1 hPRL) in case 1 and approximately 250,000-300,000 daltons (big-big2 hPRL) in case 2. Big-big1 hPRL in case 1 was converted to big and little hPRLs when the serum was treated with 2-mercaptoethanol (2-ME), but part of the big-big2 hPRL in case 2 was converted to a larger molecule. Radioactive big-big hPRL generated by mixing labeled hPRL with the serum from case 1 was eluted with the void volume on Sephadex G-100 column and was not converted to the other molecular forms after 2-ME treatment. There were two radioactive big-big hPRL on TSK G3000SW column and these estimated molecular weights were more than 300,000 daltons. The data demonstrated the existence of at least two forms of big-big hPRL in the serum and indicated that radioactive big-big hPRL may be different from these hPRLs in the serum. 相似文献
10.
E Yabuuchi I Yano H Oyaizu Y Hashimoto T Ezaki H Yamamoto 《Microbiology and immunology》1990,34(2):99-119