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排序方式: 共有6638条查询结果,搜索用时 15 毫秒
31.
32.
Tadashi Nakazawa Yoshiyuki Takami Robert Benkowski Satoshi Ohtsubo Ohashi Yukio Eiki Tayama Goro Ohtsuka Yoshinari Niimi Julie Glueck Akinori Sueoka Helmut Schmallegger Heinrich Schima Ernst Wolner Yukihiko Nosé 《Artificial organs》1997,21(7):597-601
Abstract: To be able to salvage heart failure patients, the need for an economical permanent ventricular assist device is increasing. To meet this increasing demand, a miniaturized centrifugal blood pump has been developed as a permanently implantable device. The Gyro permanently implantable model (PI-601) incorporates a sealless design with a blood stagnation free structure. The pump impeller is magnetically coupled to the driver magnet in a sealless manner. This pump is atraumatic and antithrombogenic and incorporates a double pivot bearing system. A miniaturized actuator was utilized in this system in collaboration with the University of Vienna. The priming volume of this pump is 20 ml. The overall size of the pump actuator package is 53 mm in height and 65 mm in diameter, 145 ml of displacement volume, and 305 g in weight. Testing to date has included in vitro hydraulic performance and hemolysis. This pump can provide 5 L/min against a 110 mm Hg total pressure head at 2,000 rpm and 8 Limin against 150 mm Hg at 2,500 rpm. The normalized index of hemo-lysis (NIH) value of this pump was 0.0028 g/100 L at 5 Limin against 100 mm Hg. A preliminary anatomical study revealed the possibility of the implantability of 2 such systems in biventricular bypass at a preperitoneal location. This system is feasible for use as a permanently implantable biventricular assist device. 相似文献
33.
34.
Lipid peroxidation in transplanted rat liver 总被引:2,自引:0,他引:2
35.
K. Hatayama J. Kambayashi T. Kawasaki K. Morimoto T. Ohshiro T. Mori 《Thrombosis research》1986,41(6):761-770
The interrelationship between ATP-secretion, protein phosphorylation and intracellular Ca2+ concentration ([Ca2+]i) was studied in both 32P and quin 2 loaded human platelets stimulated by thrombin or thromboxane A2 analogue (STA2). In platelets stimulated by thrombin, the degree of 47,000 dalton polypeptides (P47) phosphorylation was observed in completely dose-related manner, regardless of the amount of [Ca2+]i. In the same condition, the degree of myosin light chain (P20) phosphorylation, however, was well correlated with ATP secretion and [Ca2+]i, when platelets were stimulated by lower dose of thrombin. The similar results were obtained in platelets stimulated by STA2. These findings suggested that P20, but not P47, phosphorylation in activated platelets is mediated by a rise of [Ca2+]i and is well correlated with the secretory reaction. It was unlikely that P47 phosphorylation plays any role in promoting platelet activation. 相似文献
36.
37.
Haruhiro INOUE Yukihiko MURAOKA Kimiya TAKESHITA Narihide GOSEKI Mitsuo ENDO 《Digestive endoscopy》1993,5(3):289-292
Abstract: Since April 1991, we have studied 160 patients who had had a successful laparoscopic cholecystectomy. Nine patients who presented with chronic cholecystitis with severe local adhesion and who were also considered to require a longer operative time were selected as suitable candidates for this procedure. They were successfully treated under a zero- to four-mmHg low-pressured pneumoperitoneum procedure combined with total abdominal wall lifting using a disposable, flexible vinyl tube retractor. This method enabled exactly the same clear laparoscopic vision as is possible in the routinely-used high-pressure pneumoperitoneum even in the marginal portions of the abdominal cavity. Moreover, it facilitated early reinsufflation after the cauterization-produced smoke was exhausted, which minimized the operative time and reduced the surgeon's anxiety concerning the maintenance of a sufficiently airtight condition. We believe that this low-pressure pneumopeqitoneum procedure also benefits the poor-risk patient who has restricted cardiopulmonary function, especially during advanced laparoscopic surgery which requires a longer operative and anesthetic time. 相似文献
38.
Summary This study was undertaken to elucidate the clinical and neuropathological effects of copper administration on the macular mutant mouse. Its hemizygote, which is considered to be a model of Menkes kinky hair disease (MKHD), was injected intraperitoneally four times with 10, 20, 20 and 30 g of cupric chloride on days 4, 6, 8 and 10, respectively. The hemizygote's curly whiskers gradually straightened and the frequent tonic seizures and ataxia disappeared after the injections. The body weight also gradually increased. In the cerebral cortex, the dendritic arborization of the pyramidal neurons in both the normal littermate and the treated hemizygote developed with time and reached the maximum around day 60. In the treated hemizygote, however, the arborization of the dendrites was significantly poor in comparison with that in the normal littermate from day 20 to 90. In the cerebellum of the treated hemizygote, the abnormal Purkinje cells with the few somal sprouts, thick stem dendrite and/or poor arborization, which were seen in the non-treated hemizygote, were improved by day 30, while their focal dendritic swellings remained even on day 60. These results indicate that the copper therapy improves not only the clinical manifestations but also the neuropathological changes, especially in the cerebellum.Supported in part by Grant no. 86-05-02 from the National Center of Neurology and Psychiatry of the Ministry of Health and Welfare, Japan 相似文献
39.
Kazuo Kawasaki Junji Ohnogi 《Documenta ophthalmologica. Advances in ophthalmology》1988,70(4):301-308
The effects of penicillin G (PC-G) sodium, procaine PC-G, cloxacillin sodium (MCIPC), disodium sulbenicillin (SBPC), cefazolin sodium (CEZ), gentamicin sulfate (GM) and fosfomycin sodium (FOM) on the electroretinogram (ERG) of the human in-vitro eye-cup were studied. The oscillatory potentials (OPs) were selectively and greatly suppressed by 1.0mM PC-G sodium. The OPs and c-wave were suppressed by 0.85mM procaine PC-G. The b-wave and OPs were slightly suppressed by 1.0mM MCIPC. The a-wave, b-wave, OPs and c-wave were not deteriorated by 1.0mM SBPC. The OPs appeared to be selectively suppressed by 1.0mM CEZ. The b-wave was suppressed and the peak latencies of the OPs were delayed by 184g/ml (approximately 0.4mM) GM. The amplitudes of the a-wave and c-wave were slightly enhanced and their peak latencies were slightly delayed by 184g/ml GM. The a-wave, b-wave, OPs and c-wave were not deteriorated by 1.0mM FOM. The results of the present study on the human retina were comparable to those on the albino rabbit retina in our previous studies. 相似文献
40.
Immunogenetic analysis of gastric MALT lymphoma-like lesions induced by Helicobacter pylori infection in neonatally thymectomized mice 总被引:3,自引:0,他引:3
Fukui T Okazaki K Tamaki H Kawasaki K Matsuura M Asada M Nishi T Uchida K Iwano M Ohana M Hiai H Chiba T 《Laboratory investigation; a journal of technical methods and pathology》2004,84(4):485-492
Most gastric mucosa-associated lymphoid tissue (MALT) lymphomas are caused by Helicobacter pylori (H. pylori) infection. We previously reported that acquired lymphoid follicles with germinal centers were induced by H. pylori infection in neonatally thymectomized (nTx) mice. In the present study, we developed gastric MALT lymphoma-like lesions in nTx mice by long-term H. pylori infection, and performed immunogenetic analyses. BALB/c mice were thymectomized on the 3rd day after birth. At 6 weeks of age, mice were orally infected with 10(8) H. pylori and serially killed 2, 4, 6, and 12 months later. Normal BALB/c and noninfected nTx mice served as controls. Follicle formation occurred after 2 months of H. pylori infection in the nTx mice. Follicle formation and infiltration of intraepithelial lymphocytes progressed in a time-dependent manner. Lymphoepithelial lesions, a characteristic feature of MALT lymphoma, also occurred in a time-dependent manner (100% at 12 months). Serum immunoelectrophoresis revealed a monoclonal band (M-protein) in 30% (3/10) of mice 6 months after infection. M-protein-positive mice had amplification of one or two IgM and/or IgG heavy-chain genes in the gastric B lymphocytes, as determined with polymerase chain reaction, suggesting mono- or oligoclonality. Overexpression of Bcl-X(L) protein was immunohistologically observed in the infiltrating B lymphocytes and in some follicular B lymphocytes in 80% (8/10) of the cases at 12 months. Thus, H. pylori infection is involved in the development of gastric MALT lymphoma-like lesions in nTx mice. Our mouse model is useful for clarifying the pathogenetic mechanism of gastric MALT lymphoma by H. pylori infection. 相似文献