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11.
Yasuo Kikuchi Naoji Kubota Kazushi Maruo Yasuo Goto 《Macromolecular chemistry and physics.》1987,188(11):2631-2642
Water-insoluble polyelectrolyte complexes (PEC) were prepared by mixing methyl glycol chitosan (MGC, 1 ) and [2-(diethylamino)ethyl]dextran (EA, 2 ) with poly(potassium vinyl sulfate) (PVSK, 3 ) in aqueous solution at various hydrogen ion concentrations. Elemental analyses, IR spectroscopy, and solubilities of PEC reveal that PEC differ in molecular structure and properties according to pH. It seems that the degree of dissociation and the conformation of MGC, EA, and PVSK change with pH. PEC membranes were made by casting from solutions of all kinds of PEC, and transport phenomena through the membrane of PEC prepared in 4 wt.-% HCl solution were investigated under various conditions. The driving force of the transport depends on the membrance potential, Donnan potential, and diffusion potential, according to measurements of the transport ratio of Na+ and the electric potential difference between the left- and right-hand side of the membrane. Moreover, the permeability of K+ is higher than that of Na+. 相似文献
12.
Daisuke Kubota Takanori Kanai Fumiro Yui Tomoko Matsumoto Takahiro Kawamura Yasuhiro Itsui Eriko Okada Seishin Chin Shinya Ooka Masakazu Nagahori Kiichiro Tsuchiya Akihiro Araki Naoya Sakamoto Tatsuya Miyata Mamoru Watanabe 《Nihon Shokakibyo Gakkai zasshi》2007,104(1):42-46
A 44-year-old women developed marked myopathy one year earlier, when she was treated with intravenous prednisolone for acute severe exacerbation of ulcerative colitis. When she was admitted to our hospital for another severe exacerbation, intravenous cyclosporine A was administered as monotherapy because she could not tolerate corticosteroid. The treatment was successful and she obtained complete remission. Cyclosporine A monotherapy is considered to be a valuable alternative to proctocolectomy for severe ulcerative colitis patients who cannot tolerate corticosteroid. 相似文献
13.
14.
The effect of external gamma-irradiation on the digestive function of rat alveolar macrophages (AM) was studied by using the in vitro assay system, where the 59Fe release from AM engulfing 59Fe-iron hydroxide colloid was measured as an indicator of their digestive capability. Graded doses of gamma-irradiation up to 100 Gy had no effect on the extracellular release of 59Fe in AM cultured at 4 and 37 degrees C for 8-72 hrs postirradiation. When 10 mM Ca-DTPA was added to the culture medium, the 59Fe release was slightly depressed by irradiation at a dose of 30 Gy. It is apparent from these results that gamma-irradiation had no effect on the 59Fe transfer between cell and medium, and little effect on the catabolism of 59Fe-colloid in rat AM. 相似文献
15.
Plasma immunoreactive human atrial natriuretic peptide (hANP) levels were measured in 9 patients with chronic renal failure treated with maintenance hemodialysis in order to evaluate the effects of fluid removal and osmotic pressure. Under hemodialysis without fluid removal plasma hANP levels remained unchanged, but the levels were significantly decreased during extra-corporeal ultrafiltration (p less than 0.01). The present study provided strong evidence that the fall in plasma hANP levels in hemodialysis patients is mainly due to the reduction in circulating plasma volume. 相似文献
16.
M Imamura H Aoki H Uchida H Kubota T Murakami 《Kyobu geka. The Japanese journal of thoracic surgery》1990,43(6):502-504
Ruptured aneurysm of the sinus of Valsalva is a rare cardiac lesion. A ruptured aneurysm of the sinus of Valsalva in the right ventricle of a 64-year-old man was successfully repaired. The patient was admitted to the hospital with high fever and chest oppression. Diagnosis was made by two dimensional echocardiography, cardiac catheterization, and cardiac angiography. An aortotomy, main pulmonary arteriotomy, and right ventriculotomy were performed. There was no VSD, and the aneurysm originated from the right coronary sinus, rupturing into the right ventricle inlet portion. The ruptured aneurysm of the sinus of Valsalva was closed with a Dacron patch from inside the aorta. He is doing well after surgery. There was no heart murmur. CTR decreased and pulmonary blood flow fell to a normal value. As far as we know, this patient is the second oldest patient in Japan with surgical repair. 相似文献
17.
Senichiro Kikuchi Kazuhiko Iwata Yasunori Onishi Fumio Kubota Koichi Nisijima Hideaki Tamai Yuiko Koizumi Eiju Watanabe Satoshi Kato 《Psychiatry Research: Neuroimaging》2007,156(3):199-208
We conducted a noninvasive near-infrared spectroscopy (NIRS) study using the game of rock, paper, scissors (RPS) as a simple neurocognitive task for the prefrontal cortex (PFC) in 15 healthy volunteers. We employed an opposite “to lose” RPS task coupled with a normal “to win” RPS task, since the former requires inhibition of behavior, one of the most important functions of the prefrontal cortex. During the NIRS examination, subjects had to present one of the three RPS hands in response to hands displayed randomly on a computer screen every 1.5 s, and were required to show hands that lose to the computer, or that beat the computer. We measured the relative concentrations of oxyhemoglobin (oxy-Hb) using the prefrontal probes of the NIRS system during the tasks. The increases in oxy-Hb during the “to win” RPS task were small, but were quite large and laterally dominant during the “to lose” RPS task. The difference between the two tasks might have been due to the participants’ cognitive conflict with losing on the RPS. We conclude that losing is better than winning on the RPS as a sensitive indicator in the NIRS examination of PFC. 相似文献
18.
M Kubota 《Nippon Ganka Gakkai zasshi》1990,94(2):167-175
To define the morphological properties of muscle spindles relative to the accurate control of eyeball movement, muscle spindles were investigated in 6 extraocular muscles of three white pigs by an electron microscope. The muscle spindles were composed mainly of a thin outer capsule, nuclear bag and chain fibers. The bag fibers seem to be slow fibers and the chain fibers to be fast fibers in the external fashion, in so far as the former has a greater myofibril density than the latter. The intrafusal muscle fibers were innervated by three categories of nerve terminals; annulospiral and flower spray sensory terminals and gamma motor terminals. The annulospiral terminal was coiled sparsely on the bag fiber and densely on the chain fiber. The cross terminals were found in the pairing muscle fibers. We frequently observed that the satellite cells were controlled by the sensory terminals. It was also frequently observed that the muscle spindles were composed of only one intrafusal bag muscle fiber. It was suggested that the extraocular muscle spindles of the pig remained a primordial profile in the structure. 相似文献
19.
K Imura A Okada Y Fukui H Kawahara M Yagi A Kubota S Kanaya S Kamata Y Nagata 《JPEN. Journal of parenteral and enteral nutrition》1988,12(5):496-504
In 97 neonates receiving total parenteral nutrition in the postoperative period, clinical assessment was made for a newly devised amino acid solution (PF-I-III) from the standpoint of plasma amino acid profile and nutritional effect. These amino acid solutions prepared are characterized by the high concentration of branched-chain amino acids up to 40%, increased arginine and decreased glycine, phenylalanine and methionine as compared with commercially available solutions. In the PF group, each amino acid was kept within the range of standard value. Correlation between plasma amino acid profiles and the dose of each amino acid administered was obtained, from which minimum, standard, and maximum doses for each amino acid was determined. Based on these values, we proposed new formula for neonates which elicits no abnormal plasma amino acid pattern even when amino acids are administered at the dosage level of 1.5-2.5 g/kg/day. 相似文献
20.
A precision device was developed for quantitative measurement of the active and passive forces of the horizontal muscles in several different types of strabismus. The device consists of a tension gauge for measuring isometric muscle tension (active force) and passive length-tension (passive force), and a circular-motion guide mechanism. In normal subjects, the active force showed nearly linear changes with the eye position, as was reported in past studies. A similar relationship between the active force and the eye position was observed also in strabismus patients in our study. Normal subjects showed a stronger force in the medial than the lateral rectus muscle. Among strabismus patients, those with normal retinal correspondence (NRC)-intermittent exotropia showed a force closest to that of the normal controls. However, the force of the lateral rectus muscle was significantly greater in those with constant exotropia than in the normal controls. The active force of the medial rectus muscle was significantly smaller in those with dual retinal correspondence (DRC)-intermittent exotropia and constant exotropia. Conversely, the active force of the medial rectus muscle was significantly greater in those with esotropia, compared with the normal group. As for the passive force, there was no significant difference between the temporal passive force and the nasal passive force in the normal and esotropic groups, but the temporal passive force was significantly greater in the esotropic group. The magnitude of the force was greater in both directions when traction was applied against the muscle having the stronger active force. These results suggest that the lateral rectus muscle force is relatively stronger in patients with DRC-intermittent exotropia due to a weakness of the medial rectus muscle force, and that the absolute strength of the lateral rectus muscle force is increased in patients with constant exotropia, but in NRC-intermittent exotropia the muscle forces are almost normal. Those with esotropia are considered to have an absolute increase in the medial rectus muscle force. 相似文献