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71.
We evaluated the reliability of conventional weaning criteria from a ventilator during 33 weaning trials on 25 patients with acute respiratory failure (ARF). Of 13 criteria, a ratio of maximal voluntary ventilation to minute ventilation (MV) 2, a vital capacity 12ml·kg–1, a spontaneous respiratory rate 25 breaths·min–1, and a MV 10l·min–1 appeared to be useful for predicting successful weaning outcome. However, even using those criteria, there were many falsely-negative cases. The alveolar-arterial PO 2 gradient 350mmHg at an Fi O 2 1.0 was not useful as a predictor of weaning outcome. The present study demonstrates that conventional criteria are frequently inaccurate for predicting weaning outcomes and suggests that the use of some of these criteria may unnecessarily prolong the length of ventilator support. Since ventilation of most patients with poor oxygenation can be successfully discontinued by placing them on a continuous positive airway pressure system, these results suggest that the improvement of oxygenation is not an indispensable prerequisite for weaning from mechanical ventilators.(Okamoto K, Iwamasa H, Dogomori H, et al.: Evaluation of conventional weaning criteria in patients with acute respiratory failure. J Anesth 4: 213–218, 1990)  相似文献   
72.
Urban-rural comparison of HBV and HCV infection prevalence in eastern China   总被引:6,自引:0,他引:6  
The present study was initiated to make and urban-rural comparison of the prevalence of cases positive to hepatitis B and C virus(HBV and HCV,respectively)infection markers in densely populated eastern half of China.For this purpose.10 survey sites were selected,i.e.,six sites in urban areas(the city group;Beijing,shangahi and four provincial capitals)and four sites in rural areas(the village group;one village each in Jilin and Shandong provinces,and two villages in Shaanxi Province),About 50 adult women per site volunteered to participate,from whom 494 valid bllod samples were collected.Positivities to HBsAg(HBsAg^ ),anti-HBs(anti-HBs^ )and antiHBc(anti-HBc^ )were examined by RIA methods.and that to anti-HCV(anti-HCV^ )by either EIA or RIA.Those positive to any one of the three HBV infection markers were taken as HBV infection-positive(HBV^ ).The prevalence of HBsAg^ ,HBV^ and anti-HBc^ was 8%,70%and 2.7% in the city group,and 8%,65% and 2.0%in the village group,and no significant difference was found between the two groups.The overall prevalence was 8% for HBsAg^ ,68% for HBV^ ,and 2.4% for anti-HVC^ ,The results were discussed in reference to some 20 papers each on HBV^ and anti-HCV^ prevalence in China published since(1991),The reviewing of these papers of anti-HCV was low(well below 5%),and that no substantial difference was found between the rural and urban populations.  相似文献   
73.
A 52-year-old Japanese woman developed dermatomyositis. She had undergone a standard radical mastectomy for left breast cancer 21 years earlier. Though no physical sign of recurrent breast cancer appeared clinically, levels of tumor markers were abnormally elevated. Therefore, tamoxifen and CAF therapy were given. Further, the clinical course of dermatomyositis almost paralleled the level of serum tumor markers and the clinical course of her recurrent breast cancer. These markers were useful for detecting the recurrence, following the metastatic disease, and monitoring her response to therapy.  相似文献   
74.
Background: Nevus of Ota is common in Japanese women, but most patients are not examined ophthalmologically. Methods: We performed ophthalmologic examinations on 16 Japanese women who had had bluish pigmentation in the periorbital region, sclera, and conjunctiva since birth. Results: Fifteen patients had unilateral involvement, and one had bilateral lesions. The visual acuities were good, and the intraocular pressures were within normal range. All patients had a negative family history. Three patients had light pigmentation in the optic disc in the affected eye. Conclusion: We believe that optic disc pigmentation associated with nevus of Ota, as found in these three patients, may be common but have been rarely described.  相似文献   
75.
We have recently reported that class III antiarrhythmic drugs inhibit the muscarinic acetylcholine (ACh) receptor-operated K+ current (I K, ACh) in guinea-pig atrial cells by different molecular mechanisms. The data obtained from the patch-clamp study suggest that d,l-sotalol inhibits I K, ACh by blocking the muscarinic receptors, whereas MS-551 inhibits the K+ current by blocking the muscarinic receptors and depressing the function of the K+ channel itself and/or the guanine nucleotide-binding protein (G protein). This study was undertaken to determine whether the class III antiarrhythmic drugs d,l-sotalol and MS-551 interact with the muscarinic receptors of cardiac and peripheral tissues. Both drugs inhibited concentration dependently the specific [3H]N-methylscopolamine ([3H]-NMS) binding to membrane preparations obtained from guinea-pig atria and submandibular glands. The competition curves of these drugs for [3H]-NMS binding to glandular membranes were monophasic, suggesting competition with [3H]-NMS at a single site. Although the competition curve of d,l-sotalol for [3H]-NMS binding to atrial membranes was monophasic, that of MS-551 was biphasic and showed high- and low-affinity states of binding. d,l-Sotalol showed slightly, but significantly, higher affinity for cardiac-type muscarinic receptors (M2) than for glandular-type muscarinic receptors (M3). The inhibition constant (K i) for MS-551 in glandular membranes was also slightly greater than the high-affinity K i value for the drug in atrial membranes. In guinea-pig left atria and ilea, d,l-sotalol shifted the concentration-response curves for the negative inotropic effect and the contracting effect of carbachol in a parallel manner. The slopes of Schild plot were not significantly different from unity, suggesting competitive antagonism, and the pA2 for d,l-sotalol in left atria was slightly greater than that in ilea. MS-551 also shifted the concentration response curve for the negative inotropic effect of carbachol in atrial preparations to a greater extent than that for the contracting effect in ileal preparations, although MS-551 failed to show a pure competitive antagonism. These results suggest that both d,l-sotalol and MS-551 interact with cardiac M2 and peripheral M3 receptors, and that at high concentrations they exert anticholinergic activity in cardiac and peripheral tissues.  相似文献   
76.
A study of the knowledge, attitudes, beliefs and practices (KABP) relating to HIV/AIDS was conducted among people from Bangladesh seeking work overseas (N = 300), during February, 1997 and March, 1997. Only 26% of the respondents knew of AIDS and out of 13 basic facts concerning HIV/AIDS the mean score of the sample was 1.63 correct responses. Most of those who knew of HIV had some false beliefs about the mode of HIV transmission, for example, believing that HIV could be contracted by touching an AIDS patient, or sharing bathing facilities or eating utensils. Sex with brothel-based commercial sex workers (100%), sharing contaminated needles (93.6%) and blood transfusion from infected individuals (93.6%) were seen as the main route of HIV transmission. Printed media (69%) was the main source of AIDS information. Multiple logistic regression analysis showed that having a non-agricultural occupation (P < 0.04), being resident in Dhaka, Chandpur, Noakhali, Comilla, and Chittagong (P < 0.01), being in the habit of reading newspapers (P < 0.05), using condoms (P < 0.04), having heard about condoms (P < 0.003), having seen condoms (P < 0.005) and knowing where to buy condoms (P < 0.0005) were significantly associated with AIDS awareness. There is insufficient AIDS awareness among overseas job seekers which calls for public initiatives to provide AIDS information to them before they leave Bangladesh to work abroad.  相似文献   
77.
To investigate the adequate extent of esophagectomy and lymphadenectomy for an esophageal cancer localized at the cervicothoracic junction, the mortality and morbidity rates, survival rates, and patterns of recurrence were retrospectively analyzed in two groups—14 patients who underwent total esophagectomy with or without laryngectomy and 15 patients who underwent proximal esophagectomy with or without laryngectomy—at Kurume University Hospital from 1981 to 1996. Proximal esophagectomy with or without laryngectomy resulted in a lower hospital mortality rate and better overall survival for patients who underwent curative esophagectomy compared with total esophagectomy with or without laryngectomy. Multivariate analysis indicated that the extent of esophagectomy (total esophagectomy versus proximal esophagectomy) was not a prognostic factor. The incidence of recurrence was not different between the two groups. Lymph node metastasis or recurrence from such esophageal cancers was localized to the neck and upper mediastinum. For an esophageal cancer localized at the cervicothoracic junction, therefore, proximal esophagectomy with or without laryngectomy and with cervical and upper mediastinal lymphadenectomy could be better indicated for preselected patients.  相似文献   
78.
Few studies have investigated the relation between glucose tolerance status and ultrasonographically determined gallstone disease. Using a 75-g oral glucose tolerance test, we examined the association of impaired glucose tolerance (IGT) and non-insulin-dependent diabetes mellitus (NIDDM) with gallstone disease in Japanese men. Subjects were men aged 48 to 59 of the Japan Self-Defense Forces who received a preretirement health examination between October 1986 to December 1994. After exclusion of 12 men under insulin treatment in the consecutive series of 7637 men, 174 were found to have gallstones; 103 were at the state of postcholecystectomy, and 6899 had normal gallbladder. IGT and NIDDM were associated with a modestly increased risk of gallstone disease; adjusted odds ratios were 1.3 (95% confidence interval [CI]: 0.9–1.8) for IGT and 1.3 (95% CI: 0.8–2.0) for NIDDM after adjustment for hospital, rank, smoking, alcohol use, and body mass index. Adjusted odds ratio for IGT and NIDDM combined was 1.3 (95% CI: 1.0–1.7, p=0.08). When prevalent gallstones and postcholecystectomy were considered separately, NIDDM showed a significant, positive association with postcholecystectomy, but not with prevalent gallstones. The findings add to evidence that glucose intolerance is associated with a modest increase in the risk of gallstone disease.  相似文献   
79.
The functional regulation by dopamine (DA) receptors of serotonin (5-HT) release from the rat hippocampus was investigated by use of in vivo microdialysis. Dialysate 5-HT levels were reduced by co-perfusion of 10 M tetrodotoxin (TTX) and were elicited by K+ (60 and 120 mM) stimulation in a concentration-dependent manner. Local perfusion (10 M) and peripheral administration (20 mg/kg, i.p.) of fluoxetine produced increases in 5-HT levels. These results indicate that the spontaneous 5-HT levels in the rat hippocampus can be used as indices of neuronal origin from the serotonergic nerve terminals. The nonselective dopamine (DA) receptor agonist apomorphine (1, 10 and 100 M), when perfused through the probe over a period of 40 min, increased 5-HT release in a concentration-dependent manner. Apomorphine-induced (100 M) increases in 5-HT release was abolished by pretreatment with the selective D2 receptor antagonist, S(–)-sulphide (1 and 10 M), but not prevented by pretreatment with the selective D1 receptor antagonist, R(+)-SCH-23390 (R(+)-7-chloro-8-hydroxy-3-methyl-l-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine) (1 M). S(–)-Sulpiride and R(+)-SCH-23390 by themselves did not alter the spontaneous 5-HT levels. The 5-HT release was elevated by perfusion of the selective DA reuptake inhibitor GBR 12909 (1-[2-[bis(4-fluorophenyl)methoxy]ethyl]-4-[3-phenylpropyl]piperazine)(1, 10 and 100 M), indicating the possibility of not only exogenous but also endogenous DA-mediated facilitatory effects on 5-HT release in vivo. The 5-HT release was also elevated by perfused (±)-PPHT ((±)-2-(N-phenylethyl-N-propyl)-amino-5-hydroxytetralin)(1, 10 and 100 M), the selective D2 receptor agonist, in a concentration-dependent manner. On the other hand, (±)-PPHT (100 M) failed to increase 5-HT release in catecholamine (CA)-lesioned rats pretreated with 6-hydroxydopamine (6-OHDA)(200 g/rat, i.c.v.). The (±)-PPHT-induced (100 M) increase in 5-HT release was prevented not only by pretreatment with 10 M S(–)-sulphide but also by pretreatment with the 2-adrenoceptor antagonist idazoxan (10 M). These findings suggest that the functional regulation of 5-HT release via D2 receptors exists in the rat hippocampus. Furthermore our results indicate that the facilitatory effect of 5-HT release via D2 receptors may be mediated indirectly by noradrenergic neurons, but not mediated directly through D2 receptors located on serotonergic nerve terminals.  相似文献   
80.
To investigate cholecalciferol (vitamin D) metabolism disorders in hepatic osteodystrophy (HOD) and the effects of vitamin D, its metabolites, and calcium (Ca) on HOD, an experimental HOD model in rats was developed using carbon tetrachloride. In the serum level of 25-hydroxycholecalciferol, 1,25-dihydroxycholecalciferol, and 24R,25-dihydroxycholecalciferol, there were no significant differences between normal and control cirrhotic rats. Vitamin D supplementation significantly inhibited the atrophy of intestinal villi, reduction of bone calcium content, elevation of bone resorption, reduction of osteoid volume, and reduction of bone volume. Ca supplementation significantly increased the serum free Ca index and inhibited the elevation of bone resorption, the reduction of bone ash and Ca content, and the reduction of bone volume. This experimental study demonstrates that: (1) no marked vitamin D hydroxylation disorder was found in HOD; (2) vitamin D supplementation was effective in inhibiting HOD; and (3) sufficient Ca supplementation was also effective in inhibiting HOD.A portion of this work was presented at the 13th Annual Meeting of the Japanese Society for Bone and Mineral Research, July 1995, Fukuoka, Japan.  相似文献   
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