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991.
Six new sulfur-containing bis-iridoid glucosides, saprosmosides A-F (1-6), were isolated from the leaves of Saprosma scortechinii. From the stems of this same plant, two new iridoid glucosides, 3,4-dihydro-3-methoxypaederoside (8) and 10-O-benzoyldeacetylasperulosidic acid (12), were isolated. Their structures were elucidated by means of chemical, NMR, and mass spectroscopic methods. Additionally, 11 known iridoid glucosides were isolated and characterized as deacetylasperuloside, asperuloside, paederoside (7), deacetylasperulosidic acid (9), scandoside, asperulosidic acid, 10-acetylscandoside, paederosidic acid (10), 6-epi-paederosidic acid (11), methylpaederosidate, and monotropein. The structures of the new bis-iridoid glucosides were formed by intermolecular esterification between the glucose and carboxyl groups of three monomeric iridoid glucosides (7, 9, and 10).  相似文献   
992.
Prostaglandin E1-induced hypotension (25% reduction from the preadministration level in mean arterial pressure) was applied to thirteen patients. Eight patients among them were operated in the supine position (group I) and other five in the prone position (group II). The maintenance dose of PGE1 was considerably lower in group II than in group I (0.067µg·kg–1·min–1 vs. 0.119µg·kg–1·min–1). In group I, there was a significant increase in CI, with a significant decrease in SVRI and PVRI during PGE1-induced hypotension. Such a high dose of PGE1 (0.119µg·kg–1·min–1) was considered to have a direct dilating action on the systemic resistance bed as well as on the pulmonary vasculature. It was considered that the suppression of hypoxic pulmonary vasoconstriction could be a mechanism to increase venous admixture during PGE1-induced hypotension. In group II, there was no significant increase in CI, and no significant decrease in SVRI and PVRI. PGE1-induced hypotension can be safely applied to the anesthetized patients, but we should be careful to apply it to the patients in the prone position, because lower dose of PGE1 can induce severe hypotension, which is not accompanied by the increase in CI as occures in the patients in the supine position.(Hirose M, Yoda K, Sakai K, et al.: Comparative Study on the cardio-respiratory change during prostaglandin E1-induced hypotention in the patients in the supine and prone position. J Anesth 5: 30–35, 1991)  相似文献   
993.
IntroductionPostoperative dysphonia is mostly caused by vocal fold scarring, and careful management of vocal fold surgery has been reported to reduce the risk of scar formation. However, depending on the vocal fold injury, treatment of postoperative dysphonia can be challenging.ObjectiveThe goal of the current study was to develop a novel prophylactic regenerative approach for the treatment of injured vocal folds after surgery, using biodegradable gelatin hydrogel microspheres as a drug delivery system for basic fibroblast growth factor.MethodsVideoendoscopic laryngeal surgery was performed to create vocal fold injury in 14 rabbits. Immediately following this procedure, biodegradable gelatin hydrogel microspheres with basic fibroblast growth factor were injected in the vocal fold. Two weeks after injection, larynges were excised for evaluation of vocal fold histology and mucosal movement.ResultsThe presence of poor vibratory function was confirmed in the injured vocal folds. Histology and digital image analysis demonstrated that the injured vocal folds injected with gelatin hydrogel microspheres with basic fibroblast growth factor showed less scar formation, compared to the injured vocal folds injected with gelatin hydrogel microspheres only, or those without any injection.ConclusionA prophylactic injection of basic fibroblast growth factor -containing biodegradable gelatin hydrogel microspheres demonstrates a regenerative potential for injured vocal folds in a rabbit model.  相似文献   
994.
995.

Objective

Supracricoid laryngectomy with Cricohyoidoepiglottopexy (SCL-CHEP) is a functional organ preservation surgery for laryngeal cancers. Post-operative laryngeal function is generally promising. Some patients, however, cannot attain satisfactory functional results because of an excessively wide neoglottis resulting in an insufficient neoglottal closure. Autologous buccal fat augmentation was conducted to correct the insufficiency.

Patients and Methods

Two patients underwent intervention. Under general anesthesia, autologous fat was harvested from the buccal fat pad. Fat tissue was injected into the widest plane of the neoglottis under direct laryngoscopy; a navigation system was incorporated to identify the responsible site. Acoustic, aerodynamic, and perceptual analyses along with videofluoroscopic swallowing study and screening questionnaires were used for functional evaluation.

Results

A total of 0.8 ml (Case 1) and 0.7 ml (Case 2) of fat tissues were injected into the submucosal space of the responsible sites. Both patients experienced functional improvement subjectively after augmentation; psychological parameters for voice and swallowing also improved.

Conclusions

Buccal fat augmentation to correct insufficient neoglottal closure after SCL-CHEP was technically feasible. A navigation system was helpful for confirmation. Fat absorption occurred and one third of the volume remained at 3 and 6 months. Although, vocal measurements remained unchanged, psychological parameters for voice and swallowing improved.  相似文献   
996.
OBJECTIVES: Given that criteria for nasal surgery in individuals with obstructive sleep apnea syndrome (OSAS) have not been proposed, we investigated the effectiveness of nasal surgery for CPAP failure in patients with both severe OSAS and nasal obstruction. PATIENTS AND METHODS: Conventional nasal surgery was performed in 12 patients who were refractory to treatment by CPAP. The subject group consisted of 12 males (mean age, 54.2 +/- 9.2 years; range 39-66 years). The effect of nasal surgery was evaluated with data from preoperative and postoperative polysomunography. The nasal resistance value was first deduced to determine which OSAS patients with CPAP failure should undergo nasal surgery, compared to control values. RESULTS: Nasal surgery resulted in a significant decrease in nasal resistance, as measured by rhinomanometry, from 0.57 +/- 0.31 Pa/cm3 /sec to 0.16 +/- 0.03 Pa/cm3/sec and rendered all patients tolerant to CPAP. In addition, the lowest nocturnal oxygen saturation significantly increased from 68.3 +/- 12.1% to 75.3 +/- 7.1% after surgery. Subjectively, Epworth sleepiness scale (ESS) significantly decreased from 11.7 +/- 4.1 to 3.3 +/- 1.3 after surgery, but the number of apnea and hypopnea episodes per hour did not change significantly. In five patients, for whom it was possible to perform a CPAP titration before nasal surgery, the value decreased significantly from 16.8 +/- 1.1 to 12.0 +/- 1.9 cmH2O. The bilateral nasal resistance of the 410SAS patients with CPAP therapy (control group) was 0.24 +/- 0.11 Pa/cm3/sec. The cut off value for differentiation between CPAP failure patients and control group was determined as 0.38 Pa/cm3 /sec. CONCLUSION: Increased nasal resistance is a determinant of CPAP failure, and the surgical correction of severe nasal obstruction should thus be considered to facilitate treatment of OSAS patients with CPAP.  相似文献   
997.
Hyperthyroidism due to thyroid carcinoma is rare, and most cases are caused by hyperfunctioning metastatic thyroid carcinoma rather than primary carcinoma. Among primary hyperfunctioning thyroid carcinoma, multifocal thyroid carcinoma is exceedingly rare, with the only one case being reported in the literature. Here, we describe the case of a 62-year-old woman with multifocal functioning thyroid carcinoma. Technetium-99m (99m Tc) scintigraphic imaging showed four hot areas in the thyroid gland. Histopathological examination of all four nodules revealed papillary carcinoma, corresponding to hot areas in the 99m Tc scintigram. DNA sequencing of the thyrotropin receptor (TSH-R) gene from all nodules revealed no mutation, indicating that activation of TSH-R was unlikely in the pathophysiogenesis of hyperfunctioning thyroid carcinoma in the present case.  相似文献   
998.
BACKGROUND: The risk of colorectal cancer in relation to smoking habits has been examined mostly in Caucasians, and evidence for other ethnic groups is still scarce. METHODS: Our data came from the Japan Collaborative Cohort (JACC) Study. From 1988 through 1990, 25,260 men and 34,619 women aged 40-79 years completed a questionnaire on cigarette smoking and other lifestyle factors. Hazard ratios (HR) were estimated by fitting proportional hazards models. RESULTS: During the mean follow-up of 7.6 years through December 1997, we documented 408 incident colon cancers and 204 rectal cancers. We found a non-significant increase in colon cancer risk in male current smokers compared with never smokers. The multivariate-adjusted hazard ratios were 1.07 (95% confidence interval [CI]: 0.72-1.59) for ex-smokers and 1.23 (95% CI: 0.85-1.78) for current smokers. We however failed to observe a clear dose-response relationship between smoking intensity or duration and colon cancer risk. The adjusted hazard ratio was 1.07 (95% CI: 0.71-1.61) even for 40+ years of smoking. Almost no increase in colon cancer risk was detected for female smokers, and male smokers were not at an enhanced risk of rectal cancer. CONCLUSIONS: Cigarette smoking was not a strong risk factor for colorectal cancer even after a long-term exposure, although a weak association remains open to discussion.  相似文献   
999.
1000.

Background

Sedentary behavior is associated with cardiovascular disease, diabetes mellitus, and cancer morbidity, and watching television (TV) is an important sedentary behavior. The aim of this study is to clarify the association between TV viewing time and chronic obstructive pulmonary disease (COPD)-related mortality in Japanese adults.

Methods

Using the Cox proportional hazard model, we assessed COPD-related mortality by TV viewing time in a national cohort of 33 414 men and 43 274 women without cancer, stroke, myocardial infarction, or tuberculosis at baseline (1988–1990).

Results

The median follow-up was 19.4 years; 244 men and 34 women died of COPD. Men watching ≥4 hours/day of TV were more likely to die of COPD than those watching <2 hours/day (hazard ratio 1.63; 95% confidence interval, 1.04–2.55), independent of major confounders. No association was found in women.

Conclusions

Avoiding a sedentary lifestyle, particularly prolonged TV viewing, may help in preventing death from COPD among men.Key words: chronic obstructive pulmonary disease, sedentary behavior, obstructive lung disease, cohort study, risk assessment  相似文献   
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