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91.
Reiji Haba Shoji Kobayashi Hiroshi Miki Eiichiro Hirakawa Kousuke Saoo Takayuki Iwai Seiji Mori Masaki Ohmori 《Pathology international》1993,43(12):774-778
A case of polymorphous low-grade adenocarcinoma (PLGA) in the submandibular gland is reported. A 72 year old woman presented with a 5 year history of a gradually expanding tumor in the submandibular region. The surgical specimen revealed a relatively well demarcated tumor, 35 × 35 × 20 mm in size. Macroscopically, necrosis and hemorrhage were not seen in the solid tumor. Histologically, the tumor growth pattern was variable, composed of tubular, papillary, solid, trabecular and cribriform structures. Immunohistochemically, some tumor cells were positive for epithelial membrane antigen (EMA), S-100 protein, keratin, and carcino-embryonic antigen (CEA). Electron microscopically, prominent microvilli projected into the luminal spaces, and basal lamina and hemidesmosomes were seen in the tumor cells adjacent to the connective tissues. The submandibular gland is an extremely rare location for PLGA. To the authors' knowledge, this is the first case of its kind reported in the English literature. 相似文献
92.
93.
Poly(N-isopropylacrylamide)-grafted gelatin (PNIPAM-gelatin) serves as a temperature-induced scaffold at physiological temperature. This study was aimed at determining the effect of the graft architecture of thermoresponsive PNIPAM-gelatin on the surface topography and elastic modulus of the hydrogels prepared with different architectured PNIPAM-gelatins: the surface topography and elastic modulus were determined by atomic force microscopy (AFM). PNIPAM-gelatin surfaces showed an irregularly concavo-convex structure with a vertical interval of approximately 1 microm regardless of the weight ratio of PNIPAM to gelatin (P/G: 5.8, 12, and 18). The elastic moduli of hydrogels varied at measured sites. The mean elastic moduli of PNIPAM-gelatin with the lowest P/G were low, but increased with increasing P/G. Human umbilical vein endothelial cells adhered and spread on PNIPAM-gelatin hydrogels with the highest P/G, whereas reduced adhesion and nonspreading, round-shaped cells resided on the hydrogels with lower P/Gs. Interrelationship between elastic modulus and cell adhesion and spreading potentials were discussed from physicochemical and cellular biomechanical viewpoints. 相似文献
94.
Ogawa Y Kobayashi T Nishioka A Kariya S Hamasato S Seguchi H Yoshida S 《International journal of molecular medicine》2003,11(2):149-152
Previously, we demonstrated that human peripheral T lymphocytes revealed early apoptotic changes (annexin V-positive) and late apoptotic changes (propidium iodide-positive), at 13 and 24 h, respectively, after irradiation of 5 Gy. Changes in mitochondrial membrane potential were observed at 10 h after irradiation of 5 Gy. Subsequently, mitochondrial cytochrome c-release was confirmed. In order to elucidate the mechanism which acts prior to the mitochondrial membrane potential changes, we examined in the previous study the radiation dose and the timing of oxidative DNA damage induced in human peripheral T lymphocytes following 10 MV X-ray irradiation. As a result, the production of 8-oxoguanine, i.e., the product of oxidative DNA damage, was clearly identified starting at 10, 6, and 3 h, after 2, 5, and 20 Gy of irradiation, respectively. Therefore, we examined in the present study reactive oxygen species (ROS) formation in T lymphocytes following 5 Gy of irradiation. Using a CCD camera system, we monitored fluorescence in T lymphocytes loaded with the succinimidyl ester of dichlorodihydrofluorescein diacetate (H2DCFDA), which is non-fluorescent until oxidized by ROS. We found that ROS formation occurred immediately after irradiation, continued for several hours, and resulted in oxidative DNA damage. Therefore, the origin of hyper-radiosensitivity of T lymphocytes seemed to be the high production of ROS in the mitochondrial DNA following irradiation. 相似文献
95.
The mitogenic effect of the lymphocytosis promoting factor from Bordetella pertussis on human T gamma and non-T gamma cells 下载免费PDF全文
H Kashiwa S Hyodo T Kishi T Karakawa E Kittaka T Suzawa T Sakano T Usui 《Clinical and experimental immunology》1984,58(2):436-443
We studied the effect of lymphocytosis promoting factor (LPF), derived from the supernatant fluid of a culture of phase I Bordetella pertussis strain Tohama, on human lymphocyte proliferation. LPF was a potent mitogen for human mononuclear cells, specifically T cells. LPF failed to induce cytoplasmic immunoglobulin production by B cells. Removal of the monocytes from the T cell fraction diminished responses to LPF, but the response could be restored completely by the addition of 5.0% monocytes. These results suggest that LPF-induced cell proliferation is at least partially dependent on monocytes. In contrast to PHA, LPF stimulated T gamma cells to a greater extent than non-T gamma cells, but the magnitude of the T gamma or non-T gamma cell response was less than that of T cells, indicating that synergistic interactions between T gamma and non-T gamma cells are required for maximal response. 相似文献
96.
Fracture behavior of dental composite resins. 总被引:2,自引:0,他引:2
Fracture toughness (KIC), critical stress intensity factor, and bending strength of 3 types of commercially available dental composite resins (macrofilled, hybrid and microfilled type) were determined using three point bend specimens. Acoustic Emission (AE), which is the generation of elastic wave due to the release of energy from the localized sources in material, was also detected during the fracture toughness test. Fracture surfaces were examined by scanning electron microscope. The fracture toughness values, AE patterns, and the nature of fracture surface were analyzed to understand fracture behavior of dental composite resins and fracture mechanism for each dental composite resin are proposed. 相似文献
97.
98.
Kohzuki H Sakata S Ohga Y Misawa H Kishi T Takaki M 《The Japanese journal of physiology》2000,50(1):167-169
We investigated the influence of hyperoxia on O(2) uptake in tetanically contracting canine gastrocnemius. Hyperoxia showed neither increase in O(2) uptake nor decrease in lactate release, irrespective of increased O(2) supply, venous Po(2) and vascular resistance, as compared to normoxia, suggesting that hyperoxia decreases O(2) diffusion conductance and/or effective O(2) supply probably due to arteriovenous O(2) diffusion shunt. 相似文献
99.
Hoshino S Ohkoshi N Ishii A Shoji S 《Journal of muscle research and cell motility》2002,23(2):139-145
We investigated the expression of neuronal nitric oxide synthase (nNOS) and dystrophin in the regenerating skeletal muscles
of rats after cardiotoxin-induced myonecrosis by immunohistochemical studies and western blot analysis. In normal muscles,
nNOS was moderately immunostained on type 2B fibers, but was faintly immunostained on type 2A or type 1 fibers. In immunohistochemical
studies of regenerating muscles, nNOS was first observed at the sarcolemma of type 2B fibers on day 10, when the type discrimination
between types 2A and 2B was first detected by ATP reactions. Subsequently, the immunostaining of nNOS grew progressively stronger
in type 2B fibers, with faint staining in type 2A and type 1 fibers until day 28. Meanwhile, the immunostaining of dystrophin
grew stronger equally in all three fibers until day 21. In western blot analysis of regenerating muscles, nNOS regenerated
more slowly than dystrophin. The present data suggest that the expression of nNOS is related to the muscle fiber type differentiation,
and that the role of nNOS is related to the function of the type 2B fibers of the muscle.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
100.
Akiko Hori Masahiro Kami Sung-Won Kim Aki Chizuka Rie Kojima Osamu Imataki Michiyo Sakiyama Tamae Hamaki Yasushi Onishi Noriko Usubuchi Yukiko Kishi Naoko Murashige Kinuko Tajima Shigesaburo Miyakoshi Yuji Heike Shigeru Masuo Shuichi Taniguchi Yoichi Takaue 《Biology of blood and marrow transplantation》2004,10(1):65-72
Little information is available on the clinical characteristics of infectious complications that occur in the early period after reduced-intensity stem cell transplantation (RIST). We retrospectively investigated the clinical features of neutropenic fever and infectious episodes within 30 days after RIST in 76 patients who had received fluoroquinolones as part of their antibacterial prophylaxis. Preparative regimens included cladribine 0.66 mg/kg or fludarabine 180 mg/m2 plus busulfan 8 mg/kg. All but 1 patient survived 30 days after transplantation, and 75 patients (99%) became neutropenic within a median duration of 9 days. Neutropenic fever was observed in 29 patients (38%), and bacterial infection was confirmed in 15 (20%) of these, including bacteremia (n = 13), bacteremia plus pneumonia (n = 1), and urinary tract infection (n = 1). The causative organisms were gram-positive (n = 9) and gram-negative organisms (n = 7), with a mortality rate of 6%. Neither viral nor fungal infection was documented. Multivariate analysis showed that the presence of neutropenia at the initiation of preparative regimens was an independent risk factor for subsequent documented bacterial infections (P =.026; 95% confidence interval, 1.25-35.1). We conclude that neutropenic fever and bacteremia remain common complications in RIST. 相似文献