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41.
Expression cDNA cloning of the KGF receptor by creation of a transforming autocrine loop. 总被引:72,自引:0,他引:72
T Miki T P Fleming D P Bottaro J S Rubin D Ron S A Aaronson 《Science (New York, N.Y.)》1991,251(4989):72-75
An expression cloning strategy was devised to isolate the keratinocyte growth factor (KGF) receptor complementary DNA. NIH/3T3 fibroblasts, which secrete this epithelial cell-specific mitogen, were transfected with a keratinocyte expression complementary DNA library. Among several transformed foci identified, one demonstrated the acquisition of specific high-affinity KGF binding sites. The pattern of binding competition by related fibroblast growth factors (FGFs) indicated that this receptor had high affinity for acidic FGF as well as KGF. The rescued 4.2-kilobase complementary DNA was shown to encode a predicted membrane-spanning tyrosine kinase related to but distinct from the basic FGF receptor. This expression cloning approach may be generally applicable to the isolation of genes that constitute limiting steps in mitogenic signaling pathways. 相似文献
42.
Sekitani T Noguchi Y Hata K Fukushima T Aida T Someya T 《Science (New York, N.Y.)》2008,321(5895):1468-1472
By using an ionic liquid of 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, we uniformly dispersed single-walled carbon nanotubes (SWNTs) as chemically stable dopants in a vinylidene fluoride-hexafluoropropylene copolymer matrix to form a composite film. We found that the SWNT content can be increased up to 20 weight percent without reducing the mechanical flexibility or softness of the copolymer. The SWNT composite film was coated with dimethyl-siloxane-based rubber, which exhibited a conductivity of 57 siemens per centimeter and a stretchability of 134%. Further, the elastic conductor was integrated with printed organic transistors to fabricate a rubberlike active matrix with an effective area of 20 by 20 square centimeters. The active matrix sheet can be uniaxially and biaxially stretched by 70% without mechanical or electrical damage. The elastic conductor allows for the construction of electronic integrated circuits, which can be mounted anywhere, including arbitrary curved surfaces and movable parts, such as the joints of a robot's arm. 相似文献
43.
Ken‐ichi YAMANAKA Masahiro KANEDA Yasushi INABA Koji SAITO Kaiyu KUBOTA Miki SAKATANI Satoshi SUGIMURA Kei IMAI Shinya WATANABE Masashi TAKAHASHI 《Animal Science Journal》2011,82(4):523-530
Many observations have been made on cloned embryos and on adult clones by somatic cell nuclear transfer (SCNT), but it is still unclear whether the progeny of cloned animals is presenting normal epigenetic status. Here, in order to accumulate the information for evaluating the normality of cloned cattle, we analyzed the DNA methylation status on satellite I region in blastocysts obtained from cloned cattle. Embryos were produced by artificial insemination (AI) to non‐cloned or cloned dams using semen from non‐cloned or cloned sires. After 7 days of AI, embryos at blastocyst stage were collected by uterine flushing. The DNA methylation levels in embryos obtained by using semen and/or oocytes from cloned cattle were similar to those in in vivo embryos from non‐cloned cattle. In contrast, the DNA methylation levels in SCNT embryos were significantly higher (P < 0.01) than those in in vivo embryos from non‐cloned and cloned cattle, approximately similar to those in somatic cells used as donor cells. Thus, this study provides useful information that epigenetic status may be normal in the progeny of cloned cattle, suggesting the normality of germline cells in cloned cattle. 相似文献
44.
Shin-ichi Shimizu Takao Ito Takanori Miyoshi Yasunobu Tachibana Tsutae Ito 《Journal of General Plant Pathology》2011,77(6):326-330
Universal primers to detect Satsuma dwarf virus (SDV), including distantly related strains Citrus mosaic virus (CiMV), Navel orange infectious mottling virus (NIMV), and
Hyuganatsu virus (HV), were tested in a convenient one-step RT-PCR assay. SDV was the most broadly detected using uSDVup/uSDVdo
primers that specifically targeted a nucleotide sequence in the 3′-noncoding region that is conserved in both segmented RNAs
1 and 2 of SDV among the tested primers. Nucleotide sequence analysis confirmed that the amplified RT-PCR products could be
derived from RNAs 1 or 2 of SDV variants, some of which had interesting genetic diversity. 相似文献
45.
Sato D Awad AA Chae SH Yokota T Sugimoto Y Takeuchi Y Yoneyama K 《Journal of agricultural and food chemistry》2003,51(5):1162-1168
A simple and rapid analytical method for strigolactones, germination stimulants for the root parasitic weeds witchweed (Striga spp.) and broomrape (Orobanche spp.), has been developed using high-performance liquid chromatography connected to tandem mass spectrometry (LC/MS/MS). The natural strigolactones (strigol, sorgolactone, orobanchol, and alectrol) were clearly separated and identified by LC/MS/MS. As low as 0.1 pg/microL of strigol and 0.5 pg/microL of sorgolactone could be quantified, whereas 1 pg/microL was needed for the quantification of orobanchol (S/N > 10). Using this method, it was found that red clover produces orobanchol and alectrol but not strigol. The roots of red clover seedlings were found to produce 13, 70, 58, and 65 pg of orobanchol/plant 1, 2, 3, and 4 weeks after germination, respectively. 相似文献
46.
Summary The biomass of newborn snails was higher in paddy soil without rice plants than in the soil with rice plants. There was an inverse correlation between shell width and concentratins of Zn and Cu in snail flesh. The Zn and Cu concentrations in snail flesh were extremely high compared with those in the paddy soil surrounding the snails, possibly because snails ingest sludge, one of the main components of the composts. These results suggest that this type of snail may be used to eliminate Zn and Cu from paddy soil when composted sewage sludge has been applied. 相似文献
47.
Shimamura S Shimizu M Kobayashi M Hirao H Tanaka R Yamane Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(9):935-937
A seven-year-old, female, domestic short hair cat was presented with a history of chronic anorexia. Radiographic examination revealed a large space-occupying calcified mass in the abdominal cavity. The mass was located in pylorus and did not extend into the duodenum and surrounding tissues. Billroth I gastroduodenostomy was conducted to remove the mass. Histopathological examination of the mass showed a lymphoma. Although Recovery following the operation was excellent, the patient showed intermittent vomiting unrelated to feeding. Radiographical examination revealed a megaesophagus, which was assumed to be a complication of the Billroth I procedure, since the condition was not observed before the procedure. 相似文献
48.
Teruhisa Yotsuya Takao Ichii Minoru Sawano Tetsu Nakanishi Takeshi Ozaki 《Scientia Horticulturae》1984,24(2):177-184
Leaf buds of Japanese pear were collected in early June and early November and regarded as summer and winter dormant buds, respectively. Bud explants with and without scales were prepared from each of them, and cultured in vitro for 75 days at 25°C with 14 h photoperiod, on a medium either without growth regulators, or supplied with BA and GAs (GA3 and GA4+7), singly or in combination.When either BA or GA4+7 was contained in the medium, bud expansion occurred. Thereafter, summer dormant buds grew into shoots in the presence of BA, while winter dormant buds, although they swelled profusely, remained in a rosette. In the presence of BA, GA4+7 markedly stimulated shoot elongation of summer dormant buds, but GA3 did not. In winter dormant buds, GA4+7 not only failed to stimulate shoot elongation, but also interfered with the BA-induced swelling described above.The presence of bud scales delayed expansion of summer dormant buds, while it had little effect on winter dormant buds. The delaying effect of scales on expansion of summer buds was effectively removed by application of GA4+7 to the medium. 相似文献
49.
Fukushima R Ichikawa K Hirabayashi M Yamagami T Koyama H Hirose H Uchino T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(8):993-995
The dog of this case was a 10-year-old Shih Tzu with refractory vomiting, diarrhea and anorexia. Endoscopy revealed an unclear at gastric angle, a stenosis at pyloric antrum and congestion in duodenal mucosa. Since abnormal shadows of irregular echo-levels were disclosed by pancreas ultrasonography, serum gastrin level was determined with a suspect of gastrinoma. And an increase of serum gastrin was demonstrated. In addition, postmortem histological examination revealed that the pancreatic cells were positive for gastrin. Based on these findings, the dog was diagnosed as pancreatic gastrinoma. 相似文献
50.
Okada A Shishido T Nakano K Ito K Tamura K Fujiwara M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(11):1441-1445
In order to evaluate the physiological roles of the testicular endothelin (Edn) signaling via Edn receptor subtype-A (Ednra) in mammals, the localization of Ednra was investigated by in situ hybridization and immunohistochemistry in the testis of rats, dogs, and monkeys. For in situ hybridization, a rat Ednra RNA probe which is highly homologous to the subcloned canine and monkey Ednra (88.7% and 87.9% identical, respectively) was used. Both Ednra mRNA and protein were detected in interstitial cells and cells in the basal compartment of the seminiferous tubules, mainly Sertoli cells, as well as spermatogonia and some early spermatocytes, but not spermatids. The localization pattern of Ednra was exhibited in a same manner among species, indicating that the physiological role of Edn signaling throughout Ednra was maintained in the mammalian testis. 相似文献