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41.
Tohru Hashimoto M.D. Hironobu Nakamura Shinichi Hori Kaname Tomoda Katsuyuki Nakanishi Takamichi Murakami Takahiro Kozuka Morito Monden Mitsukazu Gotoh Chikazumi Kuroda Kenichi Wakasa Masami Sakurai 《Cardiovascular and interventional radiology》1995,18(2):82-86
Purpose: To evaluate the efficacy of transcatheter oily chemoembolization (TOCE) for hepatoceliular carcinoma (HCC) on the basis
of microscopic and macroscopic findings postembolization.
Methods: HCCs ranging in size from 0.5 to 13 cm (mean 3.6 cm) were obtained from partial hepatectomies of 100 consecutive patients
who had undergone TOCE between 20 and 246 days (mean 59.5 days) prior to surgery. The efficacy of TOCE was assessed on the
basis of the necrotic to live cell ratio of the tumors. The microscopic pattern of tumor growth was grouped into expanding
type (complete capsule formation) and replacing type (incomplete or no capsule). There were five types of macroscopic groupings:
single nodule, single nodule with extranodular growth (SNE), contiguous and noncontiguous multinodular, and massive growth
type.
Results: Among 79 cases with the expanding type, 29 (37%) had 100% HCC necrosis, but none with 100% necrosis were in the replacing
type. By macroscopic grouping, the efficacy of TOCE decreased from the single nodule type (50% of patients had 100% necrosis)
to the SNE type (21%), and the other types (9%). 相似文献
42.
Naoji Amano Saburo Yagishita Susumu Yokoi Yoji Itoh Jun Kinoshita Toshio Mizutani Takeshi Matsuishi 《Acta neuropathologica》1992,84(1):15-23
Summary This report presents a variant of Gerstmann-Sträussler syndrome (GSS). A 53-year-old female had developed slowly progressive dementia and atactic gait since the age of 45. No myoclonic jerks and periodic synchronous discharges were observed throughout the illness. The neuropathological study revealed that many amyloid plaques and widespread Alzheimer's neurofibrillary tangles (NFTs) appeared in the cerebral cortex. Characteristically, the plaques reacted with anti-prion protein and none of them reacted with anti- protein, and they were made of many components, including amyloid cores, macrophages laden with lipid granules and/or degenerated neurites. Neuropil threads were seen mainly in amyloid plaques. Moreover, plaques appeared which were confluent and laminar in arrangement in the fifth and sixth cortical layers and had a close relationship to the neuronal loss. There was no spongiform change in the cerebral cortex or cerebellum. The cerebellum was almost intact except for a few amyloid plaques. Ultrastructurally, some of the plaques simulated kuru plaques and others had many degenerated neurites possessing paired helical filaments and other accumulated organelles. GSS has been proposed to include cases with progressive ataxia, dementia and massive multifocal plaques in the brain with or without cerebral spongiform changes. The case presented here is a very peculiar case of GSS. Recently, similar cases have been reported in some large families, diagnosed as familial Alzheimer's disease. These cases may be a telencephalic form with numerous NFTs of GSS. 相似文献
43.
44.
Koichiro Yuji Shigesaburo Miyakoshi Daisuke Kato Yuji Miura Tomohiro Myojo Naoko Murashige Yukiko Kishi Kazuhiro Kobayashi Eiji Kusumi Hiroto Narimatsu Tamae Hamaki Tomoko Matsumura Masahiro Kami Takahiro Fukuda Shigeru Masuo Kazuhiro Masuoka Atsushi Wake Junichi Ueyama Akiko Yoneyama Ko Miyamoto Haruhisa Nagoshi Michio Matsuzaki Shinichi Morinaga Yoshitomo Muto Yoichi Takeue Shuichi Taniguchi 《Biology of blood and marrow transplantation》2005,11(4):314-318
We report the results of reduced-intensity unrelated cord blood transplantation (RI-UCBT) in patients with advanced malignant lymphoma. Twenty patients (median age, 46.5 years; range, 27-66 years) underwent RI-UCBT with a preparative regimen consisting of fludarabine 125 mg/m2 , melphalan 80 mg/m 2 , and 4 Gy of total body irradiation. The median infused total cell dose was 2.75 x 10(7)/kg (range, 2.3-3.4 x 10(7)/kg). Graft-versus-host disease (GVHD) prophylaxis was composed of cyclosporine or tacrolimus alone. Fifteen patients achieved primary neutrophil engraftment after a median of 20 days. Eight patients developed grade II to IV acute GVHD, and 2 developed chronic GVHD. Of the 16 patients with evaluable disease, 10 achieved a complete response. Primary disease recurred in 1 patient, and transplant-related mortality within 100 days occurred in 8 of 20 patients. The estimated 1-year probability of progression-free survival was 50%. These data suggest that RI-UCBT is a feasible option for patients with refractory lymphoma who lack an HLA-matched donor. 相似文献
45.
Although investigators have demonstrated that neocartilage can be constituted in a predetermined shape and in complex three-dimensional structures, such as a human ear, by using cell transplantation on polymer constructs, many unsolved problems still remain. The crucial issues for auricular tissue engineering consisted of optimal cell culture environment, choice of polymers, behavior of chondrocytes, study of cell-polymer constructs in an acceptable animal model, and long-term structural integrity. Here we describe our tissue engineering approaches for auricular reconstruction including auricular scaffold fabrication, in vitro chondrogenesis, in vivo immunocompromized xenograft and immunocompetent autologous animal models, and long-term follow-up. Though many current obstacles regarding auricular tissue engineering still exist, we demonstrate techniques of auricular scaffold fabrication with promising in vitro and in vivo neocartilage formation, optimal selection and application of animal models, and, to the best of our knowledge, the first report of different biodegradable biomaterial trials and the longest in vivo results (10 months) for auricular tissue engineering. 相似文献
46.
Katsumi Inoue Kenichi Abe Kenji Ando Shinichi Shirai Kei Nishiyama Michio Nakanishi Takashi Yamada Koyu Sakai Yoshihisa Nakagawa Naoya Hamasaki Takeshi Kimura Masakiyo Nobuyoshi Tadaomi Alfonso Miyamoto 《Cardiovascular pathology》2004,13(2):109-115
BACKGROUND: Angiographic regression of luminal narrowing occurs 6 months to 3 years poststenting. However, after 4 years lesions progressed gradually and late restenosis was observed in 28% of 179 Palmaz-Schatz-stented lesions during the past 10 years. Elucidating its pathogenesis is pivotal to developing preventive strategies. METHODS AND RESULTS: Histopathological and immunohistochemical studies were performed in 19 stented coronary arteries obtained from 19 patients autopsied after noncardiac death 2-7 years poststenting. The quality/severity of chronic inflammatory cells (T lymphocytes, macrophages and multinucleated giant cells) infiltration around the stent struts that is observed even in the absence of restenosis depended on the time elapsed from stenting: a) 2 years postprocedure, in spite of angiographic regression during the first year and pathologically expressed as maturation of the neointimal scar, there was chronic inflammatory response evidence: neovascularization and lymphocyte infiltration, b) > or = 3 years: the neointimal smooth muscle cells were sparse with abundant proliferation of collagen fibers. Presence of slight helper/inducer T lymphocytes and mild macrophage infiltration around the stent struts was evident immunohistochemically, c) > or = 4 years: prominent infiltration by lipid-laden macrophages with strong collagen-degrading matrix metalloproteinase immunoreactivity was observed around the struts. In two of these arteries, the surface contacting the stent was focally disrupted and covered by nonocclusive mural thrombi. CONCLUSIONS: Stainless steel stents evoke a remarkable foreign-body inflammatory reaction to the metal. These persistent peri-strut chronic inflammatory cells may accelerate new indolent atherosclerotic changes and consequent plaque vulnerability. 相似文献
47.
Bi X Gatanaga H Tanaka M Honda M Ida S Kimura S Oka S 《Journal of acquired immune deficiency syndromes (1999)》2005,38(1):1-4
The Dynabeads method showed the potential for enumerating CD4 T lymphocytes (CD4 count) in HIV-1-infected individuals. The large volume of Dynabeads required for 1 sample and complex procedure made the method expensive and not easy for use, however. To decrease the cost and simplify the procedure, we reduced the volume of the Dynabeads, added wash times, and skipped over the staining step so as to count the CD4 cells directly under an optical microscope. The CD4 count of 246 blood samples using our modified Dynabeads method (DynabeadsCD4) showed a significant correlation with that obtained by flow cytometry (FlowcytoCD4) (r = 0.91 [P < 0.0001]; slope = 1.03, intercept = -16). The sensitivity and specificity for a CD4 count less than 200 cells/microL were 79% and 94%, and for a CD4 count less than 350 cells/microL, the sensitivity and specificity were 95% and 88%, respectively. The positive and negative predictive values for a CD4 count less than 350 cells/microL were 97% and 83%, respectively. The systematic error was 8 cells/microL (95% confidence interval [CI]: 0.4-16). The cost of Dynabeads for 1 sample was less than $1.00; thus, the estimated cost per DynabeadsCD4 test is less than $3.00, including the cost of other disposable materials. Our modified method is simple, economic, and accurate enough to monitor antiretroviral therapy in resource-limited situations. 相似文献
48.
Abe Y Chinzei T Isoyama T Kobayashi S Ono T Saito I Iwasaki K Ishimaru M Baba A Kouno A Ozeki T Tohyama T Imachi K 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2003,49(3):325-332
The undulation pump total artificial heart (UPTAH) is a unique, implantable, total artificial heart (TAH) that uses undulation pumps. To achieve long-term survival in animals with physiologic hemodynamic conditions, a control method based on conductance and arterial pressure was applied to UPTAH. With this control method, called 1/R control, survival periods of 50 days (No. 0016, 49.6 kg) and 54 days (No. 0030, 42.5 kg) were obtained in adult female goats. In No. 0016, 1/R control was applied to the left pump, whereas in No. 0030, it was applied to the right pump. Another pump was used for left-right balance control. The control stability was better in No. 0030 than in No. 0016. The sucking effect of the left atrium was remarkable in No. 0016, possibly because of a time delay when left-right balance control was performed with the right pump. In No. 0016, the cause of death was probably a thrombus flown from a panus in the left atrium. It is possible that the left atrial suction effect influenced the thrombus and panus formation in the left atrium. In No. 0030, the cause of death was a small rupture of the membrane in the right pump. The rupture may have been caused by excessive negative pressure inside the pump. This pressure resulted from suction of the right atrium because of an unexpected control excursion, which was probably caused by a software bug. It will be necessary to redesign the undulation pump and improve the software to achieve longer survival periods for animals with physiologic hemodynamic conditions. 相似文献
49.
Wakabayashi Y Watanabe H Inoue J Takeda N Sakata J Mishima Y Hitomi J Yamamoto T Utsuyama M Niwa O Aizawa S Kominami R 《Nature immunology》2003,4(6):533-539
The gene Bcl11b, which encodes zinc finger proteins, and its paralog, Bcl11a, are associated with immune-system malignancies. We have generated Bcl11b-deficient mice that show a block at the CD4-CD8- double-negative stage of thymocyte development without any impairment in cells of B- or gammadelta T cell lineages. The Bcl11b-/- thymocytes showed unsuccessful recombination of V(beta) to D(beta) and lacked the pre-T cell receptor (TCR) complex on the cell surface, owing to the absence of Tcrb mRNA expression. In addition, we saw profound apoptosis in the thymus of neonatal Bcl11b-/- mice. These results suggest that Bcl11b is a key regulator of both differentiation and survival during thymocyte development. 相似文献
50.
Jun Yamauchi Hidehiro Narita Shoichi Kutsumizu Shinichi Yano 《Macromolecular chemistry and physics.》1995,196(11):3825-3831
Temperature-dependent ESR spectra of Cu2+-Cu2+ pairs in ethylene/methacrylic acid copolymer neutralized with Cu(II) were reexamined in detail. The resonance positions and the linewidths of one of the ESR fine-structure lines showed thermal distension of the Cu2+-Cu2+ distance, and the slopes in the temperature variations changed at the temperature associated with melting of the polymer crystallites. No meaningful anomalies were observed around the temperature at which the preceding endothermic transition takes place. In this transition, the Cu2+-Cu2+ pairs seems to enter a disordered state, keeping almost the same paired structure. In contrast to this irreversible order-disorder transition, the melting process in the most part of the polyethylene crystallite phases starts to impose stress upon the Cu2+-Cu2+ pairs, accompanying the slope changes of the ESR parameters. These reversible variations with remarkable thermal hysteresis are compatible with the DSC analyses. 相似文献