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21.
OBJECTIVES: The aim of this study was to investigate the effects of sandblasting, etching, and a silane coupling agent on the ability of dual-cured resin cement to bond to glass ceramics designed for in indirect adhesive restoration. METHODS: A cast glass ceramic (Olympus Castable Ceramics) with a crystalline phase consisting of mica and beta-spondumene was selected as the substrate material. The glass surfaces, which were sandblasted, polished, or etched with phosphoric acid or hydrofluoric acid (HF), were bonded with a dual-cured resin cement (Panavia Fluoro Cement) using a dentin adhesive system (Clearfil SE Bond), both with and without a silane coupling agent. A micro-shear bond test was carried out to measure the bond strength of the resin cement to the glass surface. Each glass surface was bonded and tested using the shear test. In addition, surfaces with the bonding removed after the shear bond test, the adhesive interface between the glass and cement, and an etched glass surface without any bonding, were studied morphologically using scanning electron microscopy or field emission scanning electron microscopy. RESULTS: Usage of a silane coupling agent effectively raised the bond-strength values of resin cement (Fisher's PLSD, P<0.01). The effectiveness of using phosphoric acid etching to improve bonding was not clear (Fisher's PLSD, P>0.01). HF-etching for 30s seemed to over-etch the glass surface, resulting in adverse effects on bonding (Fisher's PLSD, P<0.01). SIGNIFICANCE: The micro-shear bond strength between Olympus Castable Ceramics and resin cement can be increased by the silane coupling agent used along with an acidic primer. 相似文献
22.
Scott E Strome Elizabeth Martin Dallas Flies Dianne Khurana Diva Salomao Koji Tamada Andrei I Chapoval Jan L Kasperbauer Kerry D Olsen Lieping Chen 《Otolaryngology--head and neck surgery》2002,126(2):180-187
OBJECTIVES: CD62L was evaluated as a determinant of human pre-effector T cells. STUDY DESIGN AND SETTING: Phenotype and cytokine secretion profiles of CD62L cells were determined based on activation status. RESULTS: CD62L(Low) T cells demonstrated significantly higher secretion of interleukin (IL)-10 and interferon (IFN)-gamma than did CD62L(High) T cells. After activation, the majority of cells expressed high levels of the CD62L surface marker. Postactivation levels of IL-10 production remained elevated or unchanged. In a murine B16 melanoma model, freshly isolated CD62L(Low) tumor draining lymph nodes (TDLN) T cells showed increased secretion of IL-2 and IL-4 but not of IL-10 or IFN-gamma. The surface expression of CD62L and cytokine secretion patterns were maintained after activation with concomitant increases in IL-10. CONCLUSION: Our results provide evidence that CD62L(Low) T cells in TDLNs of progressively growing squamous cell carcinoma of the head and neck differ phenotypically and functionally from those of mouse origin. SIGNIFICANCE: Characterization of this human CD62L(Low) T cell population provides initial insight regarding novel surface markers in TDLN T cells that might correlate with antitumor reactivity. 相似文献
23.
Takamasa Kaneko Koichi Makimura Takashi Sugita Hideyo Yamaguchi 《Medical mycology》2006,44(3):227-231
We developed a simple identification kit for nine species of Malassezia (M. furfur, M. slooffiae, M. sympodialis, M. restricta, M. obtusa, M. globosa, M. pachydermatis, M. dermatis, and M. japonica) based on their biological features. This method utilizes Tween 40-based precipitate production on modified chromogenic agar (CHROMagar) Malassezia medium, growth on specific agars (Sabouraud's dextrose agar, Cremophor EL agar, Tween 60-esculin agar), and catalase reactions. This identification kit was verified with 11 type and reference strains of nine Malassezia species. An additional 26 clinical isolates were also successfully identified using the kit and the results were confirmed by molecular biological analysis. 相似文献
24.
Toru Yamaguchi Ippei Kanazawa Masahiro Yamamoto Soichi Kurioka Mika Yamauchi Shozo Yano Toshitsugu Sugimoto 《BONE》2009,44(2):174-179
The association of bone with the metabolic syndrome and its features, visceral fat accumulation or insulin resistance, remains unclear. We determined visceral and subcutaneous fat areas (V and S) by computed tomography on 187 men (28–83 years) and 125 postmenopausal women (46–82 years) with type 2 diabetes. Men whose V was 100 cm2 or more had significantly lower urinary N-terminal cross-linked telopeptide of type-I collagen (p = 0.005), higher femoral neck bone mineral density (FN-BMD) (p = 0.004), and lower prevalence of vertebral fractures (VFs) (p = 0.04) than controls. Fat mass, V, S, and lean body mass positively correlated with FN-BMD in men and with lumbar (L) and FN-BMD in women. When adjusted for weight, these correlations became negative. Urinary C-peptide positively correlated with FN-BMD in both genders. Multivariate logistic regression analysis adjusted for age, height, weight, L-BMD, duration of diabetes, and diabetes therapies identified V in men and urinary C-peptide in women as factors inversely associated with the presence of VFs [odds ratio (OR) = 0.61 per SD increase, p = 0.04, and OR = 0.32, p = 0.01, respectively]. These findings suggest that, of the components of the metabolic syndrome, body fat in gravity and hyperinsulinemia could increase FN-BMD in diabetic subjects. Visceral fat in men and hyperinsulinemia in women may protect against VFs independent of weight, L-BMD, diabetes duration, or therapies. 相似文献
25.
S Yamaguchi H Fujii S Kaneko S Yachiku F Inada T Anzai T Kobayashi K Furuta H Ishida 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》1991,82(10):1561-1567
Ultrasonotomograms of 22 kidneys were obtained in 11 patients with renal-acute renal failure (renal-ARF). The underlying diseases of renal-ARF were acute tubular necrosis in 8 patients and acute on-set chronic glomerulonephritis in 3 patients. They were treated by hemodialysis in 10 patients and intermittent peritoneal dialysis in 1 patient. Ultrasonic measurement of the size of kidneys revealed that the thickness (anterior-posterior diameter) and the ratio of thickness to length (T/L) were greater in patients with ARF than in those with chronic renal failure and normal renal function. The patients with a low value of T/L (under 0.60) had a significantly greater urine volume than those with high a value of T/L (0.60 or more). The sonographic features of renal-ARF kidneys were marked increase in parenchymal echogenicity and appearance of hypoechoic swollen renal pyramids with sharpness of the corticomedullary border. In the course of ARF, these sonographic changes gradually disappeared when the patients had recovered from ARF. However, the prognosis was poor in patients with severer sonographic findings. We believe that repeated ultrasonic examination of the kidneys in patients with renal-ARF is useful for not only differential diagnosis of post-renal urinary obstruction but evaluating the course of ARF. 相似文献
26.
T Niho C Ito Y Shibutani H Hashizume K Yamaguchi 《Nihon yakurigaku zasshi. Folia pharmacologica Japonica》1986,88(4):309-320
The pharmacological properties of MO-8282 (1,2,3,4-tetrahydro-2-methyl-9H-dibenzo [3,4: 6,7]cyclohepta [1,2-c]pyridine maleate) as an antidepressant were investigated. At doses 10 times less than those of amitriptyline, MO-8282 showed similar potencies in reducing the duration of immobility during forced swimming in rats and in potentiating stereotype induced by L-DOPA. Intermediate doses of MO-8282 reduced the duration of immobility during forced swimming, in mice as well, suppressed muricide behavior of olfactory-bulbectomized rats and antagonized clonidine-induced suppression of exploratory activity in mice. MO-8282 moderately antagonized the ptosis but not the hypothermia induced by reserpine in mice. MO-8282 exhibited weak antagonism against the tremor, lacrimation and diarrhea induced by tremorine, but its activity was milder than that of amitriptyline. The uptake of noradrenaline into rat hypothalamic synaptosomes was inhibited by MO-8282 at concentrations 20 times less than equally effective doses of amitriptyline, but the uptake of dopamine or serotonin was unaffected by MO-8282. A single oral administration of MO-8282 at a dose of 30 mg/kg accelerated noradrenaline turnover, but did not affect dopamine and serotonin turnover in the rat brain. MO-8282 strongly inhibited noradrenaline-, histamine- or adenosine-sensitive adenylate cyclase activity of guinea pig brain. Its mode of action differed from that of imipramine, rather resembling that of mianserin. MO-8282 did not affect monoamine oxidase activity of rat liver. These results suggest that the pharmacological characteristics of MO-8282 are different from those of tricyclic antidepressants and rather similar to those of mianserin, but more potent. The results, therefore, indicate that MO-8282 is possibly a novel antidepressant. 相似文献
27.
Y Wada H Hasegawa H Okuda K Yoshida N Yamaguchi 《The Japanese journal of psychiatry and neurology》1989,43(2):245-253
Kindling of the primary visual cortex (VC) was compared with that of the amygdala in cats. VC kindling was basically similar to kindling of the amygdala in that daily electrical stimulation can lead to the development of a generalized convulsion in most subjects, a growth of afterdischarges in their configuration and duration, and a reduction of the afterdischarge threshold. The kindling response of the VC differed from that of the amygdala in a number of respects, i.e., a high afterdischarge threshold, a different pattern of behavioral seizure development, an abrupt growth of electroclinical seizures coincident with the onset of a generalized convulsion, an intersubject variability in seizure susceptibility, and a marked seizure instability. In VC kindling the afterdischarge propagation into the amygdala was not observed until the generalized convulsion developed, and the early involvement of afterdischarge was seen in the pulvinar, lateral geniculate body, and superior colliculus. These data suggest that a neural mechanism different from amygdaloid kindling may participate in VC kindling, and that the subcortical structures of the visual system are involved in the preferential pathway for a seizure generalization from the VC. 相似文献
28.
Masafumi Yamaguchi Ichiro Yoshino Toshifumi Kameyama Atsushi Osoegawa Tetsuzo Tagawa Tomofumi Yohena Yoshihiko Maehara 《Annals of thoracic and cardiovascular surgery》2007,13(3):156-158
STUDY OBJECTIVE: To evaluate the safety and efficacy of small-bore, silastic drains for patients undergoing general thoracic surgery. PATIENTS AND METHODS: Twenty-five patients who received soft, small-bore, silastic drains were compared with 17 patients who received semi-rigid double lumen (DL) tubes retrospectively. RESULTS: The pain score was significantly lower in patients who received the silastic tubes in video-assisted thoracoscopic surgery (VATS) cases on postoperative days 5 and 6 , after continuous epidural analgesia had finished (P=0.018). No specific morbidity was seen in the patients who received silastic tubes. CONCLUSION: We considered that soft, small-bore silastic drains were just as effective as traditional DL tubes, but caused less pain especially in VATS cases. 相似文献
29.
Treatment strategy for synchronous metastases of colorectal cancer: is hepatic resection after an observation interval appropriate? 总被引:1,自引:1,他引:0
Yasuhiro Shimizu Kenzo Yasui Tsuyoshi Sano Takashi Hirai Yukihide Kanemitsu Koji Komori Tomoyuki Kato 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(5):535-538
Background In cases of synchronous colorectal hepatic metastases, the primary colorectal cancer strongly influences on the metastases.
Our treatment policy has been to conduct hepatic resection for the metastases at an interval of 3 months after colorectal
resection. We examined the appropriateness of interval hepatic resection for synchronous hepatic metastasis.
Materials and methods The subjects were 164 patients who underwent resection of hepatic metastasis of colorectal cancer (synchronous, 70 patients;
metachronous, 94 patients). Background factors for hepatic metastasis and postoperative results were compared for synchronous
and metachronous cases.
Results The cumulative survival rate for 164 patients at 3, 5, and 10 years postoperatively was 71.9%, 51.8%, and 36.6%, and the post-resection
recurrence rate in remnant livers was 26.8%. Interval resection for synchronous hepatic metastases was conducted in 49 cases
after a mean interval of 131 days. No difference was seen in postoperative outcome between synchronous and metachronous cases.
Conclusion The outcome was similarly favorable in cases of synchronous hepatic metastasis and in cases of metachronous metastasis. Delaying
resection allows accurate understanding of the number and location of hepatic metastases, and is beneficial in determining
candidates for surgery and in selecting surgical procedure. 相似文献
30.
Kiyohito Yamamoto Koji Onoda Yasuhiro Sawada Kazuya Fujinaga Kyoko Imanaka-Yoshida Toshimichi Yoshida Hideto Shimpo 《Annals of thoracic and cardiovascular surgery》2007,13(5):322-330
BACKGROUND: Pathological changes in vein grafts begin immediately after arterial circulation is applied to the grafts. Chemical mediator stimulation and mechanical strain induce neointimal hyperplasia and medial thickening of the vein grafts, resulting in their failure. We investigated the inhibitory effect of locally applied cilostazol, an inhibitor of cyclic adenosine monophosphate phosphodiesterase III, on neointimal hyperplasia and medial thickening of the grafts. METHODS AND RESULTS: We established a distal anastomotic stricture model of femoral vein-abdominal aorta interposition grafting in rats. In this model, neointimal hyperplasia was observed not only at the distal anastomotic sites, but also in the graft body at postoperative day 14 and was markedly progressed at day 28. A strong expression of tenascin-C was found in the media and neointima of the graft body. In the grafts around which cilostazol was administered locally using Pluronic gel, neointimal hyperplasia was significantly suppressed compared with control grafts treated with the gel alone, with the mean neointimal cross-sectional area reduced by 87.1% for the graft body and by 78.9% for the distal anastomotic sites and mean medial cross-sectional area of the graft body reduced by 54.2% at day 28 versus the control. Cilostazol treatment decreased cell proliferation and the number of tenascin-C-producing cells seen by in situ hybridization, but the expression of tenascin-C protein was not suppressed. CONCLUSION: We concluded that a single perivascular application of cilostazol inhibits neointimal hyperplasia and medial thickening of vein grafts in a rat model. 相似文献