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51.
Summary 1. The effects of some naturally occurring pungent substances, piperine, mustard oil, eugenol and curcumin, were compared to those of capsaicin in the rat isolated urinary bladder. 2. All test compounds dose-dependently contracted the rat bladder and produced desensitization toward capsaicin (1 mol/l). Development of cross-tachyphylaxis among the natural pungent substances on one hand and capsaicin on the other, suggested a common site of action on visceral primary afferents. 3. Contractile responses to piperine, mustard oil and eugenol were partially tetrodotoxin and ruthenium red-sensitive, suggesting that activation of sensory terminals by these agents takes place indirectly, as well as by a direct action on sensory receptors. 4. The presence of the secondary acylamide linkage (present in the backbone of capsaicin, but not in that of test compounds) does not appear to be essential to produce desensitization of sensory nerve terminals. Send offprint requests to R. Patacchini at the above address  相似文献   
52.
PURPOSE: The aim of this investigation was to ascertain how the length of anal canal preserved above the dentate line in stapled end-to-end ileoanal anastomosis influenced late outcome. METHODS: Two groups, high cuff group and low cuff group of nine subjects with stapled anastomosis, matched for sex, age, pouch configuration, and mean follow-up, representing the highest (median, 2.5 cm) and lowest (median, 0.7 cm) anal cuff lengths in our series, were selected. Physiologic and functional parameters were appraised preoperatively, at the time of ileostomy closure, and at 1, 3, 6, and 12 months after reestablishment of intestinal continuity. RESULTS: At one year, the drop in mean anal canal resting pressure was 13 percent in the high cuff group (not signficant) and 31 percent in the low cuff group (P <0.05); mean maximum squeezing pressure did not differ significantly from preoperative values in both groups. The mean volume of the ileal pouch was higher in the low cuff group at all insufflation pressures. The rectoanal inhibition reflex reappeared in four high cuff group patients and in none of the low cuff group patients. Mean distention pressure (cm H 2 O) and volume (ml) eliciting urge sensation were 80 and 360 in the low cuff group compared with 40 and 240 in the high cuff group (P ?0.05). Daytime bowel movements and night incontinence were significantly better in the low cuff group. No statistical differences were observed for night stool frequency, daytime incontinence, pad use (day and night), discrimination between gas and feces, ability to defer evacuation, and difficulty in emptying the pouch. CONCLUSION: Patients with stapled anastomoses and a low rectal cuff length, despite presenting lower anal resting pressure and absence of rectoanal inhibition reflex, had a better functional outcome in terms of continence than those with a high cuff length.  相似文献   
53.
The presence of mucogingival deformities often have an impact on patients in terms of esthetics and function. The variety of the conditions makes it difficult to place gingival and alveolar mucosa deformities under a single definition. Mucogingival deformities, as defined in this paper, may be congenital, developmental, or acquired defects. These may occur around natural teeth or implants and in edentulous ridges. They may be localized to soft tissues or be associated with defects in the underlying bone. They may show different degrees of severity and extension. A classification of mucogingival deformities should provide a method for identifying the different conditions in order to improve diagnosis, etiologic identification, research, treatment, and insurance evaluation.  相似文献   
54.
During the last 20 years, various conservative surgical techniques have been proposed to treat larynx cancer. On the basis of our various experiences and of the ultrastructural data on the tissues treated with radiowaves, we decided to also use radiosurgery in operations under direct microlaryngoscopy. We select 18 patients suffering from epidermoid carcinoma. These patients had been referred to our ENT clinic at the Polichnico of Palermo between 1999 and 2001. The authors describe the surgical procedures used and emphasize the advantages of radiosurgery in the treatment of larynx cancer.  相似文献   
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Retinoids have been shown to be effective in the chemoprevention and treatment of certain human malignancies. In this review, we will summarize our recent results concerning the effects of retinoids on the proliferation and differentiation of Epstein-Barr virus (EBV)-immortalized lymphoblastoid B-cell lines (LCLs), an in vitro model of EBV-related lymphoproliferative disorders arising in immunosuppressed hosts. Retinoids proved to be powerful inhibitors of the proliferation of EBV-infected LCLs in vitro, with 13-cis-retinoic acid (RA), all-trans-RA, and 9-cis-RA being the most effective compounds. Of note, retinoid-induced growth arrest in vitro appears irreversible at drug concentrations (10--6 mol/L) which may be reached in man after oral systemic therapy. The antiproliferative activity exerted by retinoids on LCLs is a generalized phenomenon usually associated with a progressive accumulation in G0/G1 phases of treated cells. The strong upregulation of p27Kipl invariably observed in cells exposed to retinoids may contribute to the decreased number of cycling cells, probably by inhibiting the transition from the G1 to S phase. Moreover, we obtained evidence indicating that the antiproliferative effects of retinoids are not dependent on the induction of terminal differentiation of EBV-immortalized B lymphocytes. In fact, the modifications induced by retinoids relative to LCL morphology, phenotype (downregulation of CD19, HLA-DR, and s-Ig, and upregulation of CD38 and c-Ig), and IgM production were highly variable among the lines tested and often only slightly relevant. Finally, the antiproliferative activity exerted by retinoids on LCLs is not mediated by a direct modulation of viral latent antigens, since EBNA-2 and LMP-1 downregulation was a late event detected only in some cell lines. These results indicate that retinoids may be useful in the medical treatment of EBV-related lymphoproliferative disorders of immunosuppressed patients, particularly in the earlier phases of these diseases.  相似文献   
59.
To evaluate toxicity and efficacy of chemotherapy in elderly patients (≥65 years of age) with advanced colorectal cancer, data from two consecutive trials conducted between 1984 and 1995 at the National Institute for Cancer Research were analysed comparing the results of treatment in those 65 years of age or older and in those younger than 65 years. Of 215 patients recruited, 82 elderly patients (median age 70 years, median performance status 1) received one of the following regimens based on 5-fluorouracil (5-FU): (1) weekly 5-FU 600 mg/m2 i.v. bolus (30 patients); (2) weekly 5-FU 600 mg/m2 bolus plus leucovorin (LV) 500 mg/m2 2-h i.v. infusion (28 patients); (3) Weekly 5-FU 2600 mg/m2 24-h continuous i.v. infusion plus LV 100 mg 4-h i.v. infusion and 50 mg orally every 4 h for five doses (24 patients). Overall, 1071 chemotherapy cycles were administered with a median number of 12 courses per patient. The main side effects were diarrhoea, observed in 38% of patients, stomatitis in 24% of patients and hand-foot syndrome in 13% of patients, and haematological toxicity affected only 15% of patients. No patient suffered grade IV toxicity. In three patients chemotherapy was discontinued because of toxicity (two patients suffered grade III diarrhoea, one patient grade III hand-foot syndrome). No significant difference in toxicity was evident between patients older than or younger than 65 years. Analysis of median dose intensity demonstrated no difference between the two groups. Overall objective response was observed in 18% (95% confidence limits 11–29) of elderly patients (15/82) in comparison with 23% (95% CL 17–32) of patients <65 years of age (31/133 pts). In conclusion, chemotherapy in elderly patients with advanced colorectal cancer is a safe and effective treatment with acceptable toxicity and comparable objective response rates. Received: 6 January 1998 / Accepted: 27 February 1998  相似文献   
60.
We report the case of a 30-year-old woman with cystic fibrosis (CF) chronically infected with Pseudomonas aeruginosa who delivered and breast-fed a healthy boy. While breast-feeding the woman had to undergo an i.v. antibiotic course with tobramycin, due to pulmonary exacerbation. Tobramycin was not detected in her milk and lactation could be continued. This is the first time that the presence of tobramycin in the milk of a CF woman during i.v. administration has been investigated.  相似文献   
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