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排序方式: 共有2274条查询结果,搜索用时 19 毫秒
91.
Yohsuke Taira Miyuki Sakai Kohyoh Soeno Takashi Sawase 《Journal of prosthodontic research》2013,57(2):88-92
PurposeThe purpose of the present study was to compare the effectiveness of an isocyanate monomer and four different silane monomers as primer components for bonding a leucite-reinforced glass ceramic (GN-Ceram Block).MethodsFour different methyl-methacrylate based primers, each with three different concentrations (1, 4, or 16wt%) of 2-methacryloxyethylisocyanate (MOI), 3-methacryloxypropylmethyldimethoxysilane (MDS), 3-methacryloxypropyltrimethoxysilane (MTS), and 3-acryloxypropyltrimethoxysilane (ATS) were prepared. A commercially available silane primer (ESPE?Sil) was also used as a control. The GN-Ceram Block specimen was ground with silicon carbide paper, rinsed, primed, and then bonded to a resin composite disk using a tri-n-butylborane-initiated self-curing luting agent. After 24-h immersion in water, the shear bond strengths were determined.ResultsThe highest level of bond strength was obtained with 4wt% MTS (45.2 MPa) and 4wt% ATS (38.7 MPa), followed by 4wt% MOI (29.8 MPa), ESPE?Sil (28.1 MPa), and 4wt% MDS (27.9 MPa). For each MTS, ATS, MOI, and MDS, the bond strengths for concentrations of 4wt% and 16wt% were not significantly different. No significant differences were found between 4wt% ATS, 4wt% MOI, ESPE?Sil, and 4wt% MDS. The use of any of these primers led to a significant increase in bond strength compared to an unprimed control (13.8 MPa).ConclusionsThe type and concentration of monomers dissolved in the primer influence the bond strength between a tri-n-butylborane resin and a leucite-reinforced glass ceramic GN-Ceram Block. The effectiveness of MOI was found to be comparable to that of MDS, ATS, and ESPE?Sil, but inferior to that of MTS. 相似文献
92.
Miyuki Kohno Hiromichi Ikawa Kunio Konuma Hiroaki Masuyama Hironori Fukumoto Eri Ogawa Sadayoshi Takahashi Nozomu Kurose 《Surgery today》2010,40(3):281-284
Gastroenteric duplication rarely occurs in locations such as the pancreas. We report a case of gastroenteric duplication of
the pancreatic tail, which was noncontiguous with the stomach and had no communication with the pancreatic duct, in a 3-year-old
girl. The cyst was enucleated by laparoscopy, without the need for pancreatic resection. The optimal treatment procedures
vary considerably, depending on where the gastroenteric duplication is located in the pancreas and, most importantly, whether
there is communication with the pancreatic duct. 相似文献
93.
We investigated biodegradation and biocompatibility of poly(organophosphazenes). We prepared poly(organophosphazenes) having different side chain groups. The blood compatibility of poly(organophosphazenes) containing fluorinated side groups, poly(bis[trifluoroethoxy]phosphazene) (PbFP) and poly([trifluoroethoxy][ethyl glycinate]phosphazene) (PFGP), without heparinization were evaluated in vitro. The deformation and aggregation of platelets adhered on PbFP and PFGP were not observed and they suppressed platelet activation. Additionally, PbFP and PFGP showed a higher degradation rate, despite their high hydrophobic nature. We found that the high mobility of water in PbFP and PFGP was one of the important factors facilitating their degradation. Their polymer structures were formed in a more open nature, indicating that water easily attacked the backbone of the phosphorus and nitrogen atoms in the poly(organophosphazene). On the other hand, the proliferation of HeLa cells cultured on poly(organophosphazene) was reduced compared with that on the control tissue culture polystyrene. 相似文献
94.
Mimura T Amano S Nagahara M Oshika T Tsushima K Nakanishi N Tanino T 《American journal of ophthalmology》2002,133(5):699-700
PURPOSE: To report a case with corneal endotheliitis and idiopathic sudden sensorineural hearing loss, in which herpes simplex virus type 1 DNA was demonstrated in the trabeculum and the aqueous humor by polymerase chain reaction. DESIGN: Interventional case report. METHODS: A 60-year-old man presented with corneal stromal edema in the right eye and sudden bilateral sensorineural hearing loss. The trabeculum excised during trabeculectomy and the aqueous humor were examined for the presence of herpes simplex virus type 1 DNA by polymerase chain reaction. RESULTS: Polymerase chain reaction demonstrated herpes simplex virus type 1 DNA in the aqueous humor and the trabeculum. CONCLUSION: Herpes simplex virus type 1 may cause corneal endotheliitis and idiopathic sudden sensorineural hearing loss simultaneously. 相似文献
95.
Peripheral injection of risperidone,an atypical antipsychotic,alters the bodyweight gain of rats 总被引:3,自引:0,他引:3
Ota M Mori K Nakashima A Kaneko YS Fujiwara K Itoh M Nagasaka A Ota A 《Clinical and experimental pharmacology & physiology》2002,29(11):980-989
1. Risperidone is an atypical antipsychotic drug that possesses 5-hydroxytryptamine 5-HT2 receptor antagonism combined with milder dopamine D2 receptor antagonism. 2. Excessive bodyweight gain is one of the side-effects of antipsychotics. Risperidone treatment causes a greater increase in the body mass of patients than treatment with conventional antipsychotics, such as haloperidol. Therefore, the present study was undertaken in order to address the aetiology of the risperidone-induced bodyweight change in rats by examining the expression of leptin, an appetite-regulating hormone produced in white adipose tissue (WAT), and uncoupling protein (UCP)-1, a substance promoting energy expenditure in the brown adipose tissues (BAT). 3. Eight-week-old male rats were injected subcutaneously with risperidone (0.005, 0.05 or 0.5 mg/kg) twice daily for 21 days. Both bodyweight and food intake were monitored daily. On day 21, rats were decapitated and their serum leptin and prolactin concentrations were measured. Expression levels of leptin, Ucp1 and beta3-adrenoceptor (beta3-AR) genes in WAT and BAT were quantified using real-time polymerase chain reaction amplification. 4. Injection of 0.005 mg/kg risperidone into rats increased food intake and the rate of bodyweight gain, as well as the augmentation of leptin gene expression in WAT. Injection of 0.05 mg/kg risperidone increased food intake and leptin gene expression in WAT, but the rate of bodyweight gain was not affected. Injection of 0.5 mg/kg risperidone caused a reduction in bodyweight gain, as well as enhanced Ucp1 gene expression in BAT and serum prolactin concentrations. The serum leptin concentration and beta3-AR gene expression in WAT and BAT were not affected by injection of 0.5 mg/kg risperidone. 5. Although the changes in food intake observed in risperidone-injected rats were rationalized neither by serum leptin nor prolactin concentrations, the reduction in the rate of bodyweight gain following injection of 0.5 mg/kg can be explained, in part, by increased energy expenditure, as revealed by the remarkable increase in the UCP-1 mRNA expression level in BAT. The role of leptin in risperidone-induced alterations in bodyweight gain remain to be clarified. 相似文献
96.
Wako M Nishimaki K Kawamura N Harima N Kubota T Yoneda K Manabe M Ansai S 《The American Journal of dermatopathology》2003,25(1):66-70
We investigated the pathway of differentiation in a case of mucinous carcinoma of the skin (MCS) arising on the right temple of a 70-year-old man. Histopathologic findings of the tumor showed evidence of apocrine-type differentiation such as distinctive decapitation secretion. Additionally, by employing a panel of antibodies, the immunohistochemical staining pattern of tumor cells was shown to be compatible with that of apocrine glands. Although the differentiation of this neoplasm remains controversial, the findings in our case suggest apocrine differentiation. 相似文献
97.
98.
There are conflicting reports regarding the effect of dietary cholesterol-oxidation products (oxysterols) on the development of atherosclerosis in experimental animals. To address this issue, apolipoprotein (Apo) E-deficient mice were fed a purified diet (AIN-93) or the same purified diet containing 0.2 g cholesterol or 0.2 g oxysterols/kg. The dietary oxysterols had no significant effect on the serum lipid levels. Although all of the diet-derived oxysterols (cholest-5-en-3beta,7alpha-diol, cholest-5-en-3beta,7beta-diol, cholestan-5alpha,6alpha-epoxy-3beta-ol, cholestan-5beta,6beta-epoxy-3beta-ol, cholestan-3beta, 5alpha, 6beta-triol, cholest-5-en-3beta-ol-7-one and cholest-5-en-3beta, 25-diol) accumulated in the serum and liver, only cholest-5-en-3beta-ol-7-one and cholestan-3beta, 5alpha, 6beta-triol accumulated significantly (P<0.05) in the aorta. The oxysterol diet did not result in elevation of the aortic cholesterol level or the lesion volume in the aortic valve. These present results indicate that exogenous oxysterols do not promote the development of atherosclerosis in ApoE-deficient mice. 相似文献
99.
Ishiguro T Jo S Oozato S Yamauchi A Yokota M 《Masui. The Japanese journal of anesthesiology》2002,51(4):425-430
Cardiology consultations are often requested preoperatively for patients with cardiovascular problems. However, there are frequently differences in the evaluation of preoperative cardiac risks among cardiologists, surgeons and anesthesiologists. In order to obtain possible solutions to this problem, we conducted a survey of preoperative cardiology consultations performed directly by cardiologists. The survey indicates a lack of interaction with anesthesiologists and insufficient information on the surgical procedures and anesthesia for cardiologists to assess compromising cardiac risks. In addition, many cardiologists suggested that exercise tolerance required for surgical procedures should be 7 METs or more for surgical patients. 相似文献
100.
Morioka M Griffin MJ 《International archives of occupational and environmental health》2002,75(1-2):78-84
OBJECTIVES: To investigate the dependence of vibrotactile thresholds on the psychophysical method used in the diagnosis of neurological dysfunction caused by exposure to hand-transmitted vibration. To compare thresholds obtained with (a) 'continuously variable' versus intermittent 'staircase' stimulation using 'yes-no' responses, and (b) 'yes-no' and 'forced-choice' responses using intermittent staircase stimulation. METHODS: Vibrotactile thresholds were measured on 12 healthy men by three different psychophysical methods. All measurements were performed with the same vibrometer in which the vibratory stimulus was applied by a probe 6 mm in diameter that protruded through a hole of 10 mm diameter in a surround, controlling both the contact force and the push force. Four stimulus frequencies (16, 31.5, 63 and 125 Hz) were used to obtain responses from FAI and FAII mechanoreceptors. RESULTS: There was a 3 to 6 dB variation in threshold due to the psychophysical method: thresholds were lower with intermittent stimulation and thresholds obtained with the 'forced-choice' procedure were lower than those obtained with the 'yes-no' procedure. Alternative explanations of the findings were offered. CONCLUSIONS: The dependence of psychophysical measurement method on vibrotactile thresholds was partly due to influencing responses via mechanoreceptor systems. It was suggested that the psychophysical measurement method had a sufficiently large effect on vibrotactile thresholds for it to be taken into account when methods for the diagnosis of neurological disorders are standardised. 相似文献