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PURPOSE: The purpose of this study was to investigate the effects of chewing and clenching on salivary cortisol levels as an indicator of stress. MATERIALS AND METHODS: Seventeen healthy dentulous subjects were given arithmetic exercises to perform within a 20-minute time limit in order to elicit stress (stress loading). In the first experiment (chewing), after stress loading, the subjects were asked to chew a paraffin wax while reading printed material (books, magazines, etc.) in silence for 10 minutes. The same procedure was then carried out again for control purposes, but this time the subjects were not required to chew wax. In the second experiment (light clenching), after stress loading, the subjects were required to carry out 5 seconds of light clenching followed by 5 seconds of rest repeatedly over a 3-minute period. The whole 3-minute process was repeated a total of three times. The control data for this second experiment consisted of measurements taken during the rest periods. Saliva specimens were collected in both experiments both before stress loading and after each procedure during 1-minute intervals to measure cortisol levels. RESULTS: In the chewing experiment, salivary cortisol levels were significantly reduced by chewing, compared with those in the controls (p < 0.05). This reduction in salivary cortisol was observed during chewing over a 10-minute period following stress loading. In the clenching experiment, salivary cortisol levels also showed a significant reduction during clenching, compared with those in the controls (p < 0.05). CONCLUSIONS: These results suggest that chewing and clenching promote relaxation in subjects under stress.  相似文献   
3.
The requirement for endoscopic access to a stricture is a major limitation of the endoscopic dilatation for the treatment of strictures in the gastrointestinal tract. We have developed the double‐balloon enteroscopy method that enables visualization of the entire small bowel. In addition, double‐balloon enteroscopy has a potential for the interventional therapy including dilatation of strictures. We present here a case of jejunal strictures in a 47‐year‐old woman with Crohn's disease successfully treated with a balloon catheter in combination with double‐balloon enteroscopy. Balloon dilation with double‐balloon enteroscopy is a promising method for the treatment of small bowel strictures in Crohn's disease.  相似文献   
4.
OBJECTIVES: Laparoscopic surgery for kidney treatment is a common procedure. However, the efficacy of this procedure in patients with several comorbidities has not been well investigated. We conducted a retrospective comparison of results of laparoscopic surgery between patients with several comorbidities and patients with no comorbidity to access the efficacy and safety of this procedure. METHODS: The subjects were 20 patients with three or more comorbidities (group A) and 46 patients with less than three comorbidities (group B). These 66 patients were 48 men and 18 women with a mean age of 62.3 years (age range, 24-83 years). The data from these two groups were compared for American Society of Anesthesiology (ASA) physical status score, previous surgical history, duration of surgery, estimated blood loss, tumor size, complications during and after surgery, conversion rates, time to oral intake, and length of hospital stay. RESULTS: The initial ASA score and age were significantly higher for the patients with comorbidities (P < 0.0001, P = 0.0008, respectively). All other variables before, during, and after surgery were similar for both laparoscopic groups. However, the incidence of atelectasis of laparoscopy was higher than that of open surgery. CONCLUSIONS: Laparoscopic nephrectomy for patients with comorbidities is safe and minimally invasive. Further investigation to prevent atelectasis is necessary.  相似文献   
5.
We evaluated nitric oxide induction in antitumor therapy consisting of anti–CD3 monoclonal antibody (anti–CD3) and interleukin–2 (IL–2), then determined the effect of nitric oxide reduction with L–NG–monomethyl arginine (LNMA) on the therapeutic methods. Female C57BL/6 mice, MCA102 (a non immunogenic, NK–resistant murine fibrosarcoma cell line), and 145–2C11 (hamster anti–murine–CD3 mAb) were utilized in an experimental hepatic metastasis model developed by injecting a tumor cell suspension into the spleen of mice. A marked increase in serum NO2+ NO1 was observed at 19 hours after anti–CD3 (10 μ, IV) and additional IL–2 administrations (40times101 U, twice, If) induced a further increase. The NO2, + NO3- elevation in spot urine in the combination therapy was not suppressed with LNMA at a dose of 100 μg/h but was significantly lowered at 300 μg/h. The efficacy of the anti–CD3 + IL–2 therapy was not diminished by LNMA administration either at 100 μg/h or at 300 μg/h.  相似文献   
6.
Fluctuating PEEP (F-PEEP) is a newly developed PEEP in which end-expiratory pressure (EEP) is periodically changed within a certain range. In a dog model with unilateral lung injury induced by the introduction of hydrochloric acid, F-PEEP in which the EEP was periodically changed from 0.5 to 1.5 kPa at periods of 6 min, and conventional PEEP (C-PEEP) with an optimized EEP of 1.0 kPa, were each applied for 30 min. F-PEEP produced a significantly greater improvement of PaO2 and intrapulmonary shunt (QS/QT) than C-PEEP, and at the low EEP phase, the greatest improvement accompanied by an increased dynamic compliance and a large cardiac output was obtained. These results suggest that F-PEEP provides a useful mode of artificial ventilation for the treatment of unilateral lung injury.  相似文献   
7.
We previously selected a group of hypertension candidate genes by a key word search using the OMIM database of NCBI and validated 525 coding single nucleotide polymorphisms (SNPs) in 179 hypertension candidate genes by DNA sequencing in a Japanese population. In the present study, we examined the association between 61 non-synonymous SNPs and blood pressure variations and hypertension. We used DNA samples taken from 1,880 subjects in the Suita study, a population-based study using randomly selected subjects. Analyses of covariance adjusting for age, body mass index, hyperlipidemia, diabetes, smoking, drinking, and antihypertensive medication revealed that 17 polymorphisms in 16 genes (APOB, CAST, CLCNKB, CTNS, GHR, GYS1, HF1, IKBKAP, KCNJ11, LIPC, LPL, P2RY2, PON2, SLC4A1, TRH, VWF) were significantly associated with blood pressure variations. Multivariate logistic regression analysis with adjustment for the same factors revealed that 11 polymorphisms in 11 genes (CAST, CTLA4, F5, GC, GHR, LIPC, PLA2G7, SLC4A1, SLCI8A1, TRH, VWF) showed significant associations with hypertension. Five polymorphisms in five genes, CAST(calpastatin), LIPC (hepatic lipase), SLC4A1 (band 3 anion transporter), TRH (thyrotropin-releasing hormone), and VWF (von Willebrand factor), were significantly associated with both blood pressure variation and hypertension. Thus, our study suggests that these five genes were susceptibility genes for essential hypertension in this Japanese population.  相似文献   
8.
In order to estimate the diagnostic validity of chemical fecal occult blood tests, i.e. orthotolidine (Shionogi A) and guajac (Shionogi B) slides for detecting cancers of the esophagus, stomach and colorectum, the authors followed up all the examinees (n=3,449) of comprehensive medical check-ups at the Center for Adult Diseases, Osaka, by means of record linkage to the Osaka Cancer Registry's files. Then, diagnostic validity was calculated based on the results of two years' follow-up. Sensitivity for the respective cancers was 20.0%, 11.8% and 62.5% for Shionogi A, and 20.0%, 5.9% and 43.8% for Shionogi B slides. Likelihood ratio for the respective cancers was 1.4, 0.8 and 4.5 for Shionogi A, and 3.3, 1.0 and 7.5 for Shionogi B. Specificity was analogous among the three cancer sites, being 86% for Shionogi A and 94% for Shionogi B. These results suggest that the diagnostic validity of chemical occult blood tests for detecting cancers of the esophagus and the stomach is very poor, and therefore imply that close examinations of these sites for screening positives is unnecessary in mass screenings for colorectal cancer.  相似文献   
9.
Intracytoplasmic lumina (ICL) in human oviduct epithelium were investigated with transmission electron microscopy. ICL were found in 43 out of 60 cases examined. They were ultra-structurally characterized by microvilli lining the lumina, periodic acid-thiocarbohydrazide-silver proteinate (PA-TCH-SP) staining-positive finely granular material in the lumina, and secretory vesicles in the cytoplasm surrounding the lumina. Although ICL were observed at various heights within the epithelium, they were mainly seen in basally located cells that did not face the oviduct lumen. Various stages of formation and development of ICL were observed in the basally located epithelial cells with secretory activities. Primary ICL were originated in the cytoplasm where the secretory granules were aggregated with smooth-surfaced tubular vesicles. Electron microscopic observations after PA-TCH-SP staining revealed that ICL were formed by fusion of the secretory granules with the tubular vesicles. ICL were enlarged into round profiles by further fusion of secretory granules and tubular vesicles, and subsequently opened to the oviduct lumen, or fused to each other to develop into large extracellular cysts within the epithelium.  相似文献   
10.
Five cases of retrograde thrombosis of former feeding arteries after removal of an arteriovenous malformation (AVM) are reported. The clinical features of these patients were studied and compared to those of 71 patients without this complication. The following characteristics were found to correlate with retrograde thrombosis: 1) advancing age of the patient; 2) large AVM size; and 3) markedly dilated and elongated feeders. It is suggested that the slow flow in the former feeding arteries that was observed immediately after AVM removal and pathological changes in these vessels due to long-standing hemodynamic stresses contributed to the development of retrograde thrombosis. Neurological manifestations related to retrograde thrombosis were noted in three of the five cases. Although infrequent, this complication should be considered as a serious possibility following removal of an AVM.  相似文献   
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