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101.
Karyotyping by PFGE of clinical isolates of Sporothrix schenckii 总被引:3,自引:0,他引:3
Takeshi Tateishi Somay Yamagata Murayama Fujio Otsuka Hideyo Yamaguchi 《FEMS immunology and medical microbiology》1996,13(2):147-154
Abstract From October 1991 to December 1992 we had eight patients with sporotrichosis at Tsukuba University Hospital in Japan. With 8 strains isolated from these patients, PFGE (pulsed-field gel electrophoresis) analyses were carried out to examine whether the karyotype of S. schenckii is distinguished by our method and whether this molecular approach is a useful means of biotyping of S. schenckii strains. Chromosomes were separated by contour-clamped homogeneous electric field (CHEF) gel electrophoresis. The strains had six to eight chromosomes and a total genome size was approx. 28 Mbp. Although these karyotypes of all the isolates looked closely similar to each other, they were grouped into three types. 相似文献
102.
Theoretical results on the geometric and electronic structures of some donor-acceptor polymers based on polythiophene (X=S), polyfuran (X=O) and polypyrrole (X=NH) were obtained, using a one-dimensional tight-binding self-consistent field crystal-orbital (SCF-CO) method at the MNDO-AM1 level of approximation. The repeat unit of these polymers consits of a bithiophene, furan or bipyrrole unit bridged by an electron-accepting group or. The optimized geometries of the polymers show a strong dependence on the nature of the electron donating group X. All the polymers studied are predicted to have band gap values ranging between 1 eV and 2 eV. An analysis of their -bond order data and of the patterns of their frontier orbitals shows they have benzenoid-like electronic structures. 相似文献
103.
Yuji Moriwaki Tetsuya Yamamoto Kei Yamaguchi Sumio Takahashi Kazuya Higashino 《Histochemistry and cell biology》1996,105(1):71-79
Tissues from male Wistar rats, fixed with 4% paraformaldehyde and embedded in paraffin, were studied with immunoperoxidase techniques using polyclonal antibodies raised against aldehyde oxidase or xanthine oxidase purified from rat liver. Immunohistochemical studies demonstrated that aldehyde oxidase-bearing cells were strongly stained in renal tubules, esophageal, gastric, intestinal and bronchial epithelium as well as liver cytoplasm. Weak but positive immunoreactivity was observed on the pulmonary alveolar epithelial cells, gastric glands and intestinal goblet cells. In contrast, it was demonstrated that cells with xanthine oxidase were strongly stained in renal tubules, esophageal, gastric, and small and large intestinal and bronchial epithelia etc. Positive immunostaining was also found in adrenal gland, skeletal muscle, spleen and cerebral hippocampus. Immunoreactivity againt aldehyde oxidase was not found in adrenal gland, spleen, mesentery or aorta, while immunoreactivity against xanthine oxidase was not found in mesentery or aorta. Although the significance of this ubiquitous and similar localization of aldehyde and xanthine oxidase seems unclear at present, these results may provide a clue as to the full understanding of the pathophysiological role of these oxidases in tissues. 相似文献
104.
Efficient production of IGG human monoclonal antibodies by lymphocytes stimulated by lipopolysaccharide,pokeweed mitogen,and interleukin 4 总被引:1,自引:0,他引:1
Kaoru Yoshinari Kenji Arai Hideki Kimura Kunio Matsumoto Yutaka Yamaguchi 《In vitro cellular & developmental biology. Animal》1996,32(6):372-377
Summary Extensive screening of the mitogens lipopolysaccharide (LPS), pokeweed mitogen (PWM), andStaphylococcus aureus Cowan I (SAC I), alone and in combination and with and without interleukin (IL) was performed forin vitro activation of regional lymph node lymphocytes from lung cancer patients for the production of human IgG, IgM, and IgA. As
assessed by electrofusion of the lymphocytes following their exposure to these agents with mouse myeloma cells and incubation
of the fused hybridoma, a remarkable stimulatory effect was shown by LPS and particularly by LPS plus IL-4, which was substantially
greater than that of either SAC I or PWM with or without various IL. Optimization studies indicated that the addition of PWM
to LPS and IL-4 in the culture medium further stimulated the human antibody (Ab) production, and that the optimal formulation
for stimulations of human IgG production was a culture medium containing 20 μg/ml of LPS, 1/500 of PWM, and 100 u/ml of IL-4. 相似文献
105.
Summary Intercolonial differences in raiding activity were investigated in the field on 9 colonies of the slavemaking antPolyergus samurai. Duration of raiding season, the mean start time of the first raiding trip in a day, the mean speed of outbound and inbound trips, and the mean distance to target nests varied significantly among colonies. The variance in start time of raiding was correlated with that in soil temperature and diurnal change pattern in soil temperature at the nest sites. The speed of trips and the first day with trips in the season also correlated with soil temperature at the nest site. Simple environmental factors well explained the observed variances in raiding activity among colonies. Therefore, raiding behaviour ofP. samurai seemed to be a stereotyped behaviour that is regulated through simple environmental factors. 相似文献
106.
107.
108.
The effects of experimental factors on protoplast formation of Prototheca zopfii Kru¨ger in 0.85 m NaCl using Macerozyme R-200 were studied based on a fractional factorial experimental design. The rate of protoplast formation was mainly affected by the incubation temperature and the age of algal cells. The optimal condition for the maximum protoplast yield was determined based on a response surface model. These were: mid-logarithmic phase cells and Macerozyme concentration of 4% at a temperature of 35°C. 相似文献
109.
110.
The replication origin of pSC101: the nucleotide sequence and replication functions of the ori region 总被引:18,自引:0,他引:18
The nucleotide sequence of a 770-bp ori region of plasmid pSC101 is presented. The sequence shows homologies to some parts of Escherichia coli oriC and phage G4 ori. Several other features are an 80-bp A + T-rich region overlapping a part of the region homologous to oriC, three direct repeats of an 18-bp sequence adjacent to the A + T-rich region, a typical promoter sequence just upstream of the longest open reading frame (ORF) and a long inverted repeat sequence overlapping the putative promoter region. Analysis of successive deletions by BAL31 exonuclease demonstrated that one of the regions homologous to oriC along with the A + T-rich region are essential for autonomous replication of the plasmid. The three 18-bp repeats are responsible for incompatibility phenotype. The region containing the promoter-like sequence is required for expression of a trans-acting function. 相似文献