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排序方式: 共有4783条查询结果,搜索用时 15 毫秒
31.
Mr N. Ishikawa S. Suda T. Sasaki T. Yamanishi H. Hosaka K. Yasuda H. Ito 《Medical & biological engineering & computing》1998,36(6):704-710
A system composed of a functional continuous magnetic stimulator (FCMS) and a saddle-type coil has been developed for non-invasive
treatment of urinary incontinence, especially stress incontinence and urge incontinence. The FCMS conditions were as follows:
2 kW maximum electrical power consumption, 800 V maximum capacitor voltage, 720 μs pulsewidth (180 μs rise time), and 5–30
Hz frequency. A frequency between 5 and 10 Hz is used to treat urge incontinence and a frequency between 25 Hz and 30 Hz is
used to treat urge incontinence. The coil (120 mm long, 90 mm wide and 50 mm thick) fits the most suitable region for this
treatment, the region from the anus to the perineum. The coil is cooled to maintain a coil temperature between 20 and 25°C
so that it can be used efficiently and safely. In experiments with anaesthetised dogs, it was confirmed that the urethral
pressure increased when the circumference of the perineum received continuous magnetic stimulation of 720 μs pulsewidth (180
μs rise time), 10Hz frequency and about 520 V capacitor voltage. This result suggests that magnetic stimulation can be effective
as a urinary incontinence therapy. 相似文献
32.
Yasutake Saekt Kouichi Shiozawa Cheol -Ho Paik Keiji Yanagisawa 《Journal of muscle research and cell motility》1991,12(2):152-160
Summary To clarify the activation-dependence of dynamic mechanical characteristics of contracting cardiac muscle, we analysed the healthy central segment length (SL) response to step decrease in tension at two different levels of barium contracture (0.2 mM and 0.5 mM Ba2+) in rat papillary muscles with a fixed initial SL. The time course of this response is thought to reflect the kinetics of actin-myosin interaction. The muscle was released stepwise from the steady contracture tension (Tc) to new steady tension levels (Tr) of varying magnitudes at 22° C. The SL responses consisted of four phases at Tr/Tc > 0.3. The amplitude of shortening in the second phase, after the initial rapid and minute shortening in the first phase, increased with an increase in amplitude of step tension reduction, and was greater at the higher activation level when compared at an identical amount of Tr/Tc. The fourth phase, after the remarkable lengthening in the third phase, was an extremely slow and minute shortening toward a new steady SL under the new tension. The duration of the second and third phase was quite insensitive to activation level at Tr/Tc > 0.85, but became longer at the higher activation level with larger amounts of tension reduction. The velocity measured from the initial quasi-steady SL shortening in the second phase increased significantly with the increase in activation level. These results are discussed in terms of cross-bridge kinetics underlying the isotonic SL transients at two different activation levels. 相似文献
33.
Yoko Kamitani Eiji Kajii Toshio Suda Shigenori Ikemoto 《Journal of human genetics》1992,37(4):271-283
Summary In order to examine expression of the Tn antigen on erythroid cells from a patient with Tn syndrome, we applied a selective two phase liquid culture system for human erythroid progenitors in peripheral blood. The cells were analyzed with flow cytometry employing an anti-Tn antibody and a lectin ofVicia villosa which recognizes only the Tn determinant. In the second phase, the Tn antigen was expressed on the cultured cells from the patient on day 3 and Tn-positive cells reached 62.7% on day 9. On the other hand, Tn-positive cells were not detected in the volunteer's cultured cells. When the patient's cells were co-cultured with the cells from a healthy voluteer, the percentage of Tn-positive cells was much lower than the expected value, suggesting that the normal cells suppressed the expression of Tn antigen on the patient's cells. 相似文献
34.
T Izawa T Komabayashi K Suda S Shinoda M Tsuboi 《The Japanese journal of physiology》1989,39(3):447-454
An acute dynamic exercise provokes the translocation of beta-adrenergic receptors (beta-AR) from light vesicle fractions to sarcolemmal membranes in rat myocardium. However, 15 min after an acute exercise the density of beta-AR in both fractions returned to the pre-exercise level. The mean maximal activity of adenylate cyclase in response to isoproterenol roughly paralleled the redistribution of beta-AR. The dose-response curves, however, were substantially shifted to the right with increase in EC50 for isoproterenol stimulation of adenylate cyclase. Thus, the sensitivity of sarcolemmal beta-AR was found to be blunted 15 min afterwards. 相似文献
35.
Kouichi Kashiwase Yoshihide Ishikawa Katsushi Tokunaga Kazue Sawanaka Hatsuya Ohashi Masami Hashimoto Minoru Furuya Ling Lin Tatsuya Akaza Kenji Tadokoro Takeo Juji 《Human immunology》1996,47(1-2):8
Two rare variants of HLA-A locus antigens, tentatively called HLA-A2K and HLA-A9HH, were serologically identified in the Japanese population. A2K and A9HH showed short reaction patterns of a series of anti-A2 and anti-A9 sera, respectively. The latter variant also reacted with some anti-A2 sera. Nucleotide sequences of full-length cDNAs for A2K and A9HH were determined. The results revealed that both antigens are encoded by previously undescribed alleles. The nucleotide sequence of the allele for A2K was identical to that of A*0207 except for a single nucleotide difference in exon 3. The nucleotide sequence of the allele for A9HH was identical to that of A*2402 except for two nucleotides in exon 2. These two nucleotides are shared by all the reported A2 alleles. These sequencing results the allele for A9HH were consistent with the serological cross-reactivity of A9HH with some anti-A2 sera. 相似文献
36.
37.
Constitutive Expression of a Bacterial Pattern Recognition Receptor, CD14, in Human Salivary Glands and Secretion as a Soluble Form in Saliva
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Akiko Uehara Shunji Sugawara Kouichi Watanabe Seishi Echigo Mitsunobu Sato Takahiro Yamaguchi Haruhiko Takada 《Clinical and Vaccine Immunology : CVI》2003,10(2):286-292
Saliva contains a number of proteins and glycoproteins that protect oral tissues, but little is known about the role of human saliva in innate immunity. Here we showed that human major salivary gland cells constitutively expressed a bacterial pattern recognition receptor, CD14, by immunohistochemistry. Human salivary gland cells in culture express CD14 mRNA and a 55-kDa CD14 protein in, but not on the cells, and secrete a soluble form with the same molecular mass. Human whole saliva contains a 55-kDa CD14, and the concentration of parotid saliva was 10-fold higher than whole saliva, which is comparable to that of serum CD14. Levels of CD14 in unstimulated whole and parotid saliva were unchanged before and after a meal and between unstimulated and stimulated saliva, indicating that saliva CD14 is constitutively secreted into the oral cavity. In contrast, lipopolysaccharide (LPS)-binding protein was below the detectable level. The saliva CD14 is functionally active in that it mediated the activation of CD14-lacking intestinal epithelial cells by LPS in a Toll-like receptor 4-dependent manner. These results suggested that saliva CD14 is important for the maintenance of oral health and possibly intestinal homeostasis. 相似文献
38.
Hamada K Sasaki T Koni PA Natsui M Kishimoto H Sasaki J Yajima N Horie Y Hasegawa G Naito M Miyazaki J Suda T Itoh H Nakao K Mak TW Nakano T Suzuki A 《Genes & development》2005,19(17):2054-2065
PTEN is an important tumor suppressor gene. Hereditary mutation of PTEN causes tumor-susceptibility diseases such as Cowden disease. We used the Cre-loxP system to generate an endothelial cell-specific mutation of Pten (Tie2CrePten) in mice. Tie2CrePten(flox/+) mice displayed enhanced tumorigenesis due to an increase in angiogenesis driven by vascular growth factors. This effect was partially dependent on the PI3K subunits p85alpha and p110gamma. In vitro, Tie2CrePten(flox/+) endothelial cells showed enhanced proliferation/migration. Tie2CrePten(flox/flox) mice died before embryonic day 11.5 (E11.5) due to bleeding and cardiac failure caused by impaired recruitment of pericytes and vascular smooth muscle cells to blood vessels, and of cardiomyocytes to the endocardium. These phenotypes depend strongly on p110gamma rather than on p85alpha and were associated with decreased expression of Ang-1, VCAM-1, connexin 40, and ephrinB2 but increased expression of Ang-2, VEGF-A, VEGFR1, and VEGFR2. Pten is thus indispensable for normal cardiovascular morphogenesis and post-natal angiogenesis, including tumor angiogenesis. 相似文献
39.
Kakinuma C Suda K Shibutani Y 《Virchows Archiv : an international journal of pathology》1999,434(1):83-89
We investigated the time-course of changes in pancreatic fibrosis accompanied with pancreatitis in WBN/Kob rats. The areas
of fibrosis and fatty replacement were analysed morphometrically, and biochemical measurements of pancreatic and plasma prolyl
hydroxylase and of pancreatic collagenase were assessed. Male rats showed acute pancreatitis at 2–3 months of age, lesions
that later underwent a transition to widespread fibrosis. The fibrosis then decreased, and the fibrotic tissue was replaced
with adipose tissue. Morphometrically, the fibrotic area reached its maximal size when the rats were 4 months old, diminishing
thereafter. The fibrosis occurred mainly in the intralobular space, and was principally attributable to type-III collagen.
Type-I collagen scarcely appeared throughout the experimental period. α-Smooth muscle actin appeared in and around myofibroblasts
that developed in an early stage and diminished later in accordance with the progressive manner of fibrosis. The plasma prolyl
hydroxylase level was higher in males than in females from 4 through 10 months of age. Pancreatic collagenase activity in
the males also increased during the same period. These findings suggest that pancreatic fibrosis in male WBN/Kob rats is affected
by the balance between prolyl hydroxylase and collagenase.
Received: 1 October 1998 / Accepted: 2 October 1998 相似文献
40.
Takahisa Sasaki Naoyuki Takahashi Shohei Higashi Tatsuo Suda 《Anatomical record (Hoboken, N.J. : 2007)》1989,224(3):379-391
Osteoclast-like multinucleated cells were formed from mouse bone marrow mononuclear cells, and their morphology on coverslips and on calcified dentine slices was compared by means of transmission electron microscopy. Addition of 1α,25-dihydroxyvitamin D3 [1α,25(OH)2D3] to bone marrow cells cultured on coverslips greatly stimulated the formation of multinucleated cells within 8 days. These multinucleated cells had the cytological features of osteoclasts (abundant pleomorphic mitochondria, a large number of vacuoles and lysosomes, many stacks of Golgi membranes, and an extensive canalicular system), but they developed neither ruffled borders nor clear zones. The multinucleated cells appeared to result from direct fusion of mononuclear progenitor cells, whose structural features were similar to those of multinucleated cells. Like isolated osteoclasts, both multinucleated cells and their precursors exhibited an intense reaction for tartrate-resistant acid phosphatase (TRACP) in the cisterns of endoplasmic reticulum and lysosomes. Multinucleated cells formed from alveolar macrophages in the presence of 1α,25(OH)2D3 were totally negative for TRACP reaction. When marrow cells were cultured on dentine slices in the presence of 1α,25(OH)2D3, some of the multinucleated cells were located in the shallow resorption lacunae of dentine surfaces, and they developed the characteristic ruffled borders and clear zones. The narrow extracellular spaces of the ruffled borders, the adjacent pale endocytotic vacuoles, and the dark lysosomes located in the perinuclear cytoplasm of the multinucleated cells contained numerous apatite crystals delete in resorption lacunae. These results indicate that (1) the multinucleated cells formed on coverslips from mouse marrow cells treated with 1α,25(OH)2D3 exhibit non-functional basic features of osteoclast morphology, and (2) differentiation of the multinucleated cells into functional osteoclasts requires some components of calcified dentine. 相似文献