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31.
Microvascular free tissue transfer has gained world-wide acceptance as a means of reconstructing post-oncologic surgical defects in the head and neck region. Since 1977, the authors have introduced this reconstructive procedure to head and neck reconstruction after cancer ablation, and a total of 2372 free flaps were transferred in 2301 patients during a period of over 23 years. The most frequently used flap was the rectus abdominis flap (784 flaps: 33.1 percent), followed by the jejunum (644 flaps: 27.2 percent) and the forearm flap (384 flaps: 16.2 percent). In the reported series, total and partial flap necrosis accounted for 4.2 percent and 2.5 percent of cases, respectively. There was a significant statistical difference ( p < 0.05) in complete flap survival rate between immediate and secondary reconstruction cases. The authors believe that the above-mentioned three flaps have been a major part of the armamentarium for head and neck reconstruction because of a lower rate of flap necrosis, compared to other flaps.  相似文献   
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To investigate the effect of flavonoids on the activation of p72(syk) (Syk) protein tyrosine kinase which plays a pivotal role in the high affinity IgE receptor-mediated degranulation of mast cells, we picked out 10 flavonoids, classified them into 4 series, and examined their effects on the activation of Syk and on the degranulation of human mast cells. Flavones and flavonols showed clear inhibition, whereas flavanones and isoflavones had either weak or no effect on Syk enzymatic activity induced by amino acid peptide corresponding to the activation loop domain and on IgE-dependent degranulation of human cultured mast cells (HCMC). On the basis of calculated logP (ClogP) values as a prediction of compound lipophilicity, some flavonoids were speculated to have low lipophilicity, the reason for poor cell permeability. A significant relationship was observed between the inhibition of Syk activity and HCMC degranulation attributable to flavonoids when the ClogP values of the compounds were taken into account (r(2)=0.89). These results suggested that the impairment of mast cell degranulation by several flavonoids classified into flavones and flavonols might be mediated via inhibition of the intracellular activation of Syk.  相似文献   
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Abstract. In this study, we assessed whether baroreflex sensitivity (BRS) is influenced by risk factors of cardiovascular disease. Subjects of this study were 95 elderly people (40 males and 55 females; mean age ± SD, 66.6±1.6 years) who underwent a medical check-up. BRS was determined as the gain of transfer function in baroreflex arc by spectral analysis of mean blood pressure and R-R interval variabilities in low-frequency band (0.04–0.15 Hz). Gender-related differences in BRS and relationships between BRS and various risk factors of cardiovascular disease were investigated. The value of BRS was significantly higher in males [10.7±3.7 (SD) ms/mmHg] than in females [9.0±4.0 ms/mmHg, p< 0.05]. However, this gender-related difference disappeared when other variables were taken into account in the multivariate model. Multiple regression analyses showed independent inverse relationships between BRS and heart rate [b=–0.016±0.004 (SE) bpm, =–0.39], and between BRS and platelet count [b=–0.002±0.001 × 103/µl, =–0.22]. Our results indicated that BRS is inversely related to platelet count in the elderly population. The precise mechanism of this correlation is unknown, but platelet factors released from platelet aggregates can potentially influence vascular function and modify BRS, or there is a common underlying determinant responsible for the covariation.  相似文献   
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Epicutaneous antigen challenge in passively sensitized mice with IgE produces a biphasic cutaneous response which peaks 1 h (immediate-phase reaction) and 24 h (late-phase reaction; LPR) after the antigen challenge. In this model, anaphylactic degranulation and interleukin 6 (IL-6) expression between 4 and 8 h are observed in resident mast cells as the preceding stage of LPR. Prednisolone at a dose of 3 mg kg(-1) clearly inhibited the LPR when administered 2 h before and 4 h after antigen challenge. Slight or no inhibition of LPR was observed by prednisolone administered 6-12 h after challenge. Histologically, prednisolone treatment 2 h before antigen challenge completely inhibited edema and inflammatory cell infiltration, while treatment at 6 h did not at all. In order to investigate the relationship between inhibition of LPR by prednisolone and mast cell activation, the effects of prednisolone on degranulation of mast cells and IL-6 expression in mast cells were investigated. 8 h after antigen challenge, prednisolone clearly inhibited the increase in the number of anaphylactic degranulated and IL-6-positive mast cells by administration 2 h before challenge, but did not affect it by administration 6 h after challenge. These data indicate that the inhibitory mechanism of prednisolone on LPR, at least, involves the inhibition of mast cell activation before LPR.  相似文献   
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A 65-year-old man was diagnosed to have Crohn's disease in 1989. In 1991, frequent bronchitis developed, and bronchoesophageal fistula was diagnosed by esophagography. On esophagography and aortography, the disease was diagnosed to be Type IV based on Braimbridge's classification accompanied by pulmonary sequestration. A thoracoscope-assisted fistelectomy was performed. This paper reports the findings of a fistelectomy assisted by thoracoscopy for the treatment of a Type IV bronchoesophageal fistula according to Braimbridge's classification accompanied by Crohn's disease.  相似文献   
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The use of nonsteroidal anti-inflammatory drugs has been suggested to have a chemopreventive effect against colon carcinoma, through the inhibition of cyclooxygenases 1 and 2, in patients with familial adenomatous polyposis and in animal models. Acarbose, an alpha-glycosidase inhibitor, may also be chemopreventive. In order to examine the effects of these drugs we employed APC gene knockout mice randomized into 3 groups, one for treatment with piroxicam (0.05% concentration in drinking water), one for acarbose (0.04% concentration in food) and another for the control. After 14 weeks of treatment, mice were killed for quantitation of gastric and intestinal adenomas. Tumor multiplicity in the whole gastrointestinal tract decreased from 33.89±13.07 tumors/mouse in the control group to 17.05±7 tumors/mouse in the piroxicam-treated group ( P <0.001). The decrease in the acarbose-treated group (29.68±12.86 tumors/mouse) was not significant ( P >0.05). The number of tumors ≥3 mm in diameter was also quantified in all gastrointestinal segments. The number of such tumors in the piroxicam group was decreased to 0.56±1.2 tumors/mouse from the control value of 3.78±1.17 tumors/mouse ( P <0.001), while in the acarbose-treated group the number decreased to 2.36±1.7 tumors/mouse ( P <0.01). Thus, piroxicam decreases the size and number of gastrointestinal adenomas in APC 1309 knockout mice, while acarbose decreases only the size.  相似文献   
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