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51.
52.
M Yoshida M Asano Y Morita I Kaetsu K Imai T Mashimo H Yuasa H Yamanaka U Kawaharada K Suzuki 《Biomaterials》1989,10(1):16-22
Cisplatin, cis-dichlorodiamine platinum (II), was incorporated in a needle-type copolymer formulation (0.8 mm diameter, 6 mm long) by radiation-induced polymerization. The copolymer used was copoly(diethylene glycol dimethacrylate/polyethylene glycol #600 dimethacrylate, 80/20 vol%). This copolymer, containing 6 mg of cisplatin, was implanted into the kidney of adult male Wistar rats (420 +/- 20 g). A total of 70 d was required for 100% release of cisplatin in vivo. The kidney tissue surrounding the formulation was strongly necrotized by the action of cisplatin. Two layers of necrosis could be distinguished: necrotic tissue surrounding the formulation and necrobiotic tissue surrounding the necrotic tissue. The amount of necrotic tissue changed markedly over time, but no change was apparent in the amount of necrobiotic tissue. The maximal amounts of necrotized tissue were observed 14 d after implantation: 3100 microns and 600 microns thick for the necrotic and necrobiotic tissues, respectively. 相似文献
53.
54.
Harley BA Spilker MH Wu JW Asano K Hsu HP Spector M Yannas IV 《Cells, tissues, organs》2004,176(1-3):153-165
The experimental study of peripheral nerve regeneration has depended heavily on the use of a nerve chamber in which the stumps of the transected nerve are inserted. A large variety of chamber fillings and chamber types have been used in an effort to induce a higher quality of regeneration across the gap initially separating the two stumps. In this study we studied the morphology of nerves regenerated across a 15 mm gap following implantation of a series of five chambers. The chambers were fabricated from type I collagen and possessed identical pore volume fractions as well as average pore diameters, but differed in cross-link density continuously along the series. The residual mass of the implanted chambers at 9 weeks was observed to increase continuously with increasing cross-link density along the series, indicating a continuous decrease in degradation rate. The quality of regenerated nerves, determined by the number of large diameter fibers (A-fibers) per nerve, the average diameter of all axons and the ratio of area occupied by axons (N-Ratio), was superior at an intermediate level of chamber degradation rate. The maximal quality of peripheral nerve regeneration corresponded to an optimal degradation rate with an estimated chamber half-life of approximately 2-3 weeks following implantation. A speculative mechanistic explanation of the observed optimum focuses on the hypothetical role of cell and cytokine traffic that may take place through holes in the chamber generated by the degradation process. The data show the presence of a hitherto unreported optimal chamber degradation rate that leads to regenerated nerves of maximum quality. 相似文献
55.
I-J as an Inducible T Cell Receptor for Self 总被引:4,自引:0,他引:4
"Jedenfalls, wenn man davorsteht, dann sieht man sich selbstaber eben nicht wie in einem gewöhnlichen Spiegel, versteht sich. Man sieht nicht sein Äusseres, sondern man sieht sein wahres inneres Wesen. so wie es in Wirklichkeit beschaffen ist. Wer da durch will, der muß - um es mal so auszudrücken -in sich selbst hineingehen."
Die undendliche Geschichte, bei Michael Ende, K. Thiehemanns Verlag, Stuttgart, 1979. 相似文献
Die undendliche Geschichte, bei Michael Ende, K. Thiehemanns Verlag, Stuttgart, 1979. 相似文献
56.
When HANA protein of HVJ (Sendai virus) was denatured by dithiothreitol treatment, concanavalin A added to the system or influenza virus hemagglutinin reconstituted with treated HVJ-envelope to form hybrid by SM-2 dialysis method could not replace a role of HANA for hemolysis. Binding of the treated samples to erythrocytes was restored by them, however. Thus, a hypothesis is proposed that intactness of not only F but also HANA protein of HVJ is required for envelope-cell fusion, in other words, HANA protein of HVJ may play some positive role other than binding in the process of the virus-induced hemolysis. 相似文献
57.
Shishido T Clarke IC Williams P Boehler M Asano T Shoji H Masaoka T Yamamoto K Imakiire A 《Journal of biomedical materials research. Part B, Applied biomaterials》2003,67(1):638-647
Three THAs with cementless monolithic alumina ceramic sockets and cementless Co-alloy stems were retrieved because of aseptic loosening after 17 and 24 years. At revision heads and cups were marked for orientation. Maps were drawn of wear patterns with the use of light microscopy and surveyed by SEM. In a simulator experiment 28-mm-diameter alumina heads and liners were used. The cups were mounted inverted in a hip simulator and run with calf serum as the lubricant. The hip loads were 2 kN maximum and a 1-Hz frequency for 20 million cycles. Wear severity was classified into five grades. In retrieved implants, SEM analysis showed that the main wear zones (MWZ) had Grade 4 wear. The peripheral wear zones (PWZ) showed grain pull-out regions (Grade 5 wear). These corresponded to neck-socket impingement and head-acetabular cup separation. Gray was due to transferred CoCr particles from the stem. In the simulator study, the MWZ had only localized areas of grain pull out surrounded by polished surface regions (Grade 4 wear) at 20 million cycles; stripe wear was not seen. The alumina ceramic bearings proved excellent up to 22 years in simulator studies and clinical studies. However, microseparation kinematics would be necessary in the simulator to duplicate the more peripheral wear zones. 相似文献
58.
A microsomal fraction was obtained from the zona glomerulosa of the bovine adrenal cortex. Glucose-6-phosphate activity of the fraction was found to be much lower than that of the liver. Contents of RNA and phospholipids, besides electron microscopic findings, of the fraction also indicate that it is rich in smooth-surfaced endoplasmic reticulum. Distribution of cytochrome P-450 in the zona glomerulosa was studied using various fractions including the microsomal fraction described above. The amount of cytochrome P-450 in mitochondria and that in microsomes were determined to be 0.73 and 0.32 nmoles/mg protein, respectively. The CO-difference spectrum was affected not only by the concentration of added deoxycholate but also by the incubation time after addition. Approximately 40-50% of cytochrome P-450 in the samples were converted to cytochrome P-420 within 20-30 seconds of incubation with deoxycholate. 相似文献
59.
Motonobu Nishimura MD Takashi Nishimura MD Masayuki Ishikawa MD Ayumu Masuoka MD Nobuyuki Okamura MD Keiko Abe MD Takahiro Matsuoka MD Mika Iwazaki MD Kazuhito Imanaka MD Haruhiko Asano MD Shunei Kyo MD 《Journal of artificial organs》2006,9(4):209-213
The presence of a significant organ dysfunction does not immediately exclude patients from consideration for treatment with
a left ventricular assist system (LVAS). However, in treating morbid circulatory shock patients with multiple organ failure,
it is important to know the preoperative and postoperative factor or factors related to the recovery of the damaged organ
function. In this study, we retrospectively analyzed patients receiving a LVAS at our institution and tried to determine the
important factors related to the survival of patients with multisystem failure. Twenty-seven patients who underwent LVAS placement
at Saitama Medical School Hospital between 1993 and 2003 were included in this study. The preoperative risk factors analyzed
were renal dysfunction, respiratory dysfunction, hepatic dysfunction, the existence of active infection, and the combination
of all four factors. As a postoperative factor, the pump flow index (mean LVAS pump flow during the first 2 weeks after LVAS
surgery divided by the body surface area) was analyzed. None of the analyzed preoperative factors could predict survival after
LVAS surgery, but a pump flow index of less than 2.5 l/min/m2 had a significant relationship with death after LVAS surgery. Further analysis revealed that all the patients with a pump
flow index of 3.0 l/min/m2 or more could overcome preoperative organ dysfunction. Congestive heart failure patients with multisystem failure need luxury
pump flow for successful LVAS surgery; this factor could be especially important in device selection and postoperative management. 相似文献
60.
Yoshiyuki Suehara Shinji Kohsaka Takuo Hayashi Keisuke Akaike Aiko Kurisaki-Arakawa Shingo Sato Eisuke Kobayashi Sho Mizuno Toshihide Ueno Takeshi Morii Tomotake Okuma Taisei Kurihara Nobuhiko Hasegawa Kei Sano Keita Sasa Taketo Okubo Youngji Kim Hiroyuki Mano Tsuyoshi Saito 《Clinical orthopaedics and related research》2021,479(4):838