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排序方式: 共有1621条查询结果,搜索用时 15 毫秒
1.
K S Shiba K Kanamori H Cho N Furuhata T Harada A Shiba M Nakao 《Clinica chimica acta; international journal of clinical chemistry》1988,172(1):77-84
Proteins in normal human urine were clearly fractionated into 26 bands with molecular weights from 14,000 to 230,000 by means of one-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) coupled with silver staining. The main band contained uromucoid, and the second main band had albumin. However, when urine samples from healthy persons were electrophoresed in the absence of SDS using polyacrylamide gel or agarose gel, or a cellulose acetate membrane, albumin but not uromucoid, frequently formed the main protein band. It is suggested that this is due to the complexing of uromucoid subunits to form a large molecule which cannot penetrate into the gel. In order to correctly fractionate all the proteins contained in normal human urine, it was concluded that it was best to treat a urine sample with SDS with pre-condensation, fractionate it by SDS-PAGE and stain fractionated proteins by a highly sensitive method such as silver staining. 相似文献
2.
3.
Vasodilator effects of sarafotoxins and endothelin-1 in spontaneously hypertensive rats and rat isolated perfused mesentery 总被引:1,自引:0,他引:1
K Kitazumi T Shiba K Nishiki Y Furukawa C Takasaki K Tasaka 《Biochemical pharmacology》1990,40(8):1843-1847
Sarafotoxins (SRTa, SRTb and SRTc) and ET-1 produced a potent vasodilator effect in spontaneously hypertensive rats in vivo and in rat isolated perfused mesenteries in vitro. Among these peptides SRTc demonstrated the most potent vasodilator activity, and was three times more active than SRTa in both preparations. These peptides induced endothelium-dependent vasodilatation in vitro and pretreatment with methylene blue inhibited this effect, while exposure to the antagonists of other vasodilators did not. In contrast, [nitrophenylsulfenylated Trp21]SRTc, SRTc(1-18) and reduced and S-carboxymethylated SRTc caused no vasodilatation in either animal model; the vasodilator effect of acetylated SRTc was less potent than that of SRTc. These results suggest that (i) the vasodilatations of these peptides may be exerted through the release of endothelium derived relaxing factor; (ii) the C-terminal Trp21 and disulfide bonds are essential; and (iii) the N-terminal amino group plays an important role in vasodilator activity. 相似文献
4.
Vasoconstrictor response of large cerebral arteries of cats to endothelin, an endothelium-derived vasoactive peptide 总被引:6,自引:0,他引:6
A Saito R Shiba S Kimura M Yanagisawa K Goto T Masaki 《European journal of pharmacology》1989,162(2):353-358
Endothelin, a 21-amino acid peptide produced by vascular endothelial cells, caused a sustained constriction of isolated large cerebral arteries of cats in a dose-dependent manner. The increased tone of the tissue did not return to the resting level after repeated washings. No vasodilator response was evoked by endothelin in the presence of an active tone. The contractile response of cerebral arteries was not inhibited by rubbing of the endothelium, cold storage denervation or indomethacin. In contrast, nicardipine or diltiazem antagonized the endothelin-induced contraction non-competitively. No contraction was evoked by endothelin in a Ca2+-free solution while the addition of Ca2+ ions in the presence of endothelin in a Ca2+-free solution caused a sustained contraction. Ca2+-induced contraction in the Ca2+-free solution containing endothelin was also inhibited by nicardipine. Therefore, endothelin causes a direct contraction of the smooth muscles of cat cerebral arteries, probably by activating the influx of Ca2+ ions through L-type Ca2+ channels of smooth muscles. 相似文献
5.
Resolution of homonymous visual field loss documented with functional magnetic resonance and diffusion tensor imaging. 总被引:5,自引:0,他引:5
Masaki Yoshida Masahiro Ida Thien Huong Nguyen Marie-Therese Iba-Zizen Luc Bellinger Jean Louis Stievenart Takehiko Nagao Shinsuke Kikuchi Takaaki Hara Takuya Shiba Kenji Kitahara Emmanuel Alain Cabanis 《Journal of neuro-ophthalmology》2006,26(1):11-17
A 68-year-old man developed right homonymous hemianopic paracentral scotomas from acute infarction of the left extrastriate area. He was studied over the ensuing 12 months with visual fields, conventional MRI, functional MRI (fMRI), and diffusion tensor imaging (DTI). As the visual field defect became smaller, fMRI demonstrated progressively larger areas of cortical activation. DTI initially showed that the lesioned posterior optic radiations were completely interrupted. This interruption lessened in time and had disappeared by one year after onset. fMRI and DTI are innovative measures to follow functional and structural recovery in the central nervous system. This is the first reported application of these imaging techniques to acute cerebral visual field disorders. 相似文献
6.
K Shinozaki T Kawasaki J Kambayashi M Sakon E Shiba M Ou T Mori 《Methods and findings in experimental and clinical pharmacology》1992,14(9):663-665
Species differences in platelet aggregation induced by platelet-activating factor (PAF) were investigated by using the same procedure of platelet preparation and biological assay. Washed platelets of six different species (horses, dogs, rats, rabbits, sheep and guinea pigs) were prepared employing the same method and platelet aggregation was induced by C16-PAF. Horse platelets were most sensitive to PAF (8.0 x 10(-12) M) and rabbit platelets activated by 5.0 x 10(-11) M PAF were also sensitive enough to detect PAF in clinical samples. 相似文献
7.
Impact of portal venous pressure on regeneration and graft damage after living-donor liver transplantation. 总被引:4,自引:0,他引:4
Shintaro Yagi Taku Iida Kentaro Taniguchi Tomohide Hori Takashi Hamada Koji Fujii Shugo Mizuno Shinji Uemoto 《Liver transplantation》2005,11(1):68-75
Several reports claim that portal hypertension after living-donor liver transplantation (LDLT) adversely affects graft function, but few have assessed the impact of portal venous pressure (PVP) on graft regeneration. We divided 32 adult LDLT recipients based on mean PVP during the 1st 3 days after LDLT into a group with a PVP > or = 20 mm of Hg (H Group; n = 17), and a group with a PVP < 20 mm of Hg (L Group; n = 15). Outcome in the H Group was poorer than in the L Group (58.8 vs. 92.9% at 1 year). Peak peripheral hepatocyte growth factor (HGF) during the 1st 2 weeks was higher in the H Group (L: 1,730 pg/mL, H: 3,696 pg/mL; P < .01), whereas peak portal vascular endothelial growth factor (VEGF) level during the 1st week was higher in the L Group (L: 433 pg/mL, H: 92 pg/mL; P < .05). Graft volume (GV) / standard liver volume (SLV) was higher in the H Group (L / H, at 2, 3, and 4 weeks, and at 3 months: 1.02 / 1.24, .916 / 1.16, .98 / 1.27, and .94 / 1.29, respectively; P < .05). Peak serum aspartate aminotransferase, bilirubin levels, and international normalized ratio after LDLT were significantly higher in the H Group, as was mean ascitic fluid volume. In conclusion, early postoperative PVP elevation to 20 mm of Hg or more was associated with rapid graft hypertrophy, higher peripheral blood HGF levels, and lower portal VEGF levels; and with a poor outcome, graft dysfunction with hyperbilirubinemia, coagulopathy, and severe ascites. Adequate liver regeneration requires an adequate increase in portal venous pressure and flow reflected by clearance of HGF and elevated VEGF levels. 相似文献
8.
Hiroaki Shiba Takeyuki Misawa Susumu Kobayashi Tokuyasu Yokota Kyonsu Son Katsuhiko Yanaga 《Journal of gastrointestinal surgery》2007,11(4):549-551
A 41-year-old Chinese woman was admitted to our hospital with epigastric pain. Computed tomography detected a heterogeneous
enhancement tumor fed by the left gastroepiploic artery in the left lower quadrant and cholelithiasis. Excision of the tumor
in the greater omentum and cholecystectomy were performed laparoscopically. Histological findings confirmed a diagnosis of
hemangiopericytoma with low-grade malignancy. To our knowledge, hemangiopericytoma of the greater omentum is very rare, and
only 12 cases were reported in English literature. We report a case of hemangiopericytoma arising in the greater omentum and
review the literature. 相似文献
9.
Ikuyo Watanabe Kazuhiro Tsukamoto Tadayoshi Shiba M. Emi 《Journal of human genetics》1998,43(1):75-76
Matrix Gla protein (MGP) is an 84-residue, vitamin K-dependent protein expressed by chondrocytes and vascular smooth muscle
cells, and is a potent regulator of calcium deposition in cartilage and arterial wall. We isolated a polymorphic dinucleotide
CA repeat marker from a genomic clone containing the human MGP gene. This polymorphism will be useful in genetic studies of arteriosclerosis and osteoporosis.
Received: November 5, 1997 / Accepted November 27, 1997 相似文献
10.
Pathological changes induced by formaldehyde in open-ended rat tracheal implants preexposed to benzo(a)pyrene 总被引:1,自引:0,他引:1
The promotion effects of 0.1% formaldehyde (HCHO) in phosphate-buffered saline (PBS) were tested in rat tracheal implants preexposed to a minimal carcinogenic dose of 468 micrograms benzo(a)pyrene (BAP) released over one month from 865 micrograms BAP-beeswax pellets. At the time of pellet removal, the tracheas were made into open-ended, flow-through, tracheal implants (FTTI), and exposed twice/week to HCHO for 30 weeks. Morphological alterations in the FTTI were monitored biweekly by collection of exfoliated cells from the luminal washings for cytopathologic diagnosis, and periodically by sacrificing animals for histopathology. FTTI exposed to the BAP followed by 30 weeks of HCHO had extensive squamous metaplasia, a high proliferation index of 7.87 [3H]thymidine-labeled cells/mm basement membrane, and foci of moderate and marked atypia. Clear diagnosis of some of the lesions was difficult because of the acute toxic effects of the repeated exposures to HCHO. These effects were seen in the tissues as well as in the exfoliated cells, which attest to the latter as an efficient, non-destructive, method for determining the responses of the tracheas to exposure to toxic and carcinogenic agents. FTTI exposed to BAP followed by twice weekly PBS, had a mostly flattened epithelium, and a low proliferation index (0.39). FTTI exposed to beeswax pellets, followed by the HCHO had a relatively high proliferation index (4.20) in a mucociliary epithelium exhibiting some basal cell hyperplasia. Control FTTI had a normal mucociliary epithelium with a proliferation index of 1.52 [3H]thymidine labeled cells/mm basement membrane. 相似文献