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991.
We have tested whether our previous finding in normal subjects that the disappearance of insulin from plasma obeys saturation kinetics alone also applies to type I diabetic patients. In six long-term diabetic patients steady state plasma insulin concentrations resulting from constant insulin infusion at different rates were compared with the predictions of three models for the kinetics of insulin in plasma. The models allowed the existence of non-saturable (first order equation) or saturable (Micha?lis-Menten equation) mechanisms, or both. The minimal acceptable model included saturation kinetics alone in four subjects and first order kinetics alone in two subjects. The clearance of insulin in diabetic patients, calculated from the best fitting model, was 18.0 (median, range 10.0-23.7) ml X kg-1 X min.-1 versus 25.0 (18.6-47.1) ml X kg-1 X min.-1 in six normal subjects (2p = 0.008). Insulin thus disappears from plasma at a lower rate in diabetic patients than in normal subjects at physiological plasma concentrations.  相似文献   
992.
In the period 1979-83 a total of 232 penetrating corneal transplantations were performed with organ culture preserved donor material. Forty-two operations were made à chaud for central corneal ulcerations. The results of these interventions are reported and discussed. The surgery presented no serious problems and on first post-operative day the anterior chamber was reformed in all cases, and pain was relieved. Patients were confined to bed only for 1 day. Graft deswelling was slightly retarded compared to planned surgery, but all functioning grafts obtained normal thickness. The overall graft survival rates after 6, 12 and 18 months were 66, 53 and 48%, respectively. For herpetic ulcers the survival after 18 months was 49% and for non-herpetic ulcers 47%. The grafts failed in all cases where it had been necessary to employ grafts of more than 10 mm. This latter group was comprised of the non-herpetic cases; were they excluded, the graft survival rate would increase to 60%. Among cases with a clear graft the median visual acuity after 18 months was 0.33 (range less than 0.1-0.67). Excluding cases with a non-corneal cause of visual reduction, the median visual acuity was 0.4 (range 0.33-0.67). It is concluded that grafting can be successfully employed in the treatment of central ulcers, as it not only restitutes tissue integrity, but also preserves useful vision.  相似文献   
993.
Acid application in the esophagus and esophageal distension were undertaken in pigs. One group (n = 9) had operatively induced esophagitis. The other group (n = 7) was normal. We found no discrepancy between the groups neither in inspiratory pressure nor in expiratory PCO2 nor in plasma concentrations of pancreatic polypeptide. The results indicate inability to elicit vagal responses from the acid-infused esophagus of pigs.  相似文献   
994.
Forty-five patients scheduled for major abdominal or intrathoracic surgery were assigned at random to two different groups. One group received 0.3 mg and the other 0.9 mg of buprenorphine epidurally to abolish postoperative pain. The first dose was given immediately upon arrival in the ICU, irrespective of pain. Subsequent medication was given on demand. The duration of action and side-effects were recorded. Both doses produced excellent and long-lasting pain relief, but no statistically significant difference was found between the groups, with regard to either the duration of action or the occurrence of side-effects.  相似文献   
995.
The peroperative and postoperative blood loss was determined in 36 patients undergoing transurethral prostatectomy (TUR-P) using a photometric method. Seventeen patients were randomly allocated to epidural and 19 patients to general anaesthesia. No significant differences were found between the two groups in the total blood loss peroperatively, the corrected blood loss peroperatively (ml/g/min) or the blood loss postoperatively. The systolic blood pressures were equal in the two groups and no correlation between blood loss and blood pressure was demonstrated. The blood loss per g resected tissue was fairly constant and independent of prostatic weight, but bleeding per minute operating time increased significantly with prostatic size. As the total peroperative blood loss increases with operating time, rapid surgery is a possibility of reducing blood loss in TUR-P. Visual estimation of blood loss during TUR-P of larger glands was unreliable with underestimates of about 100 per cent in one third of the patients, when bleeding exceeded 400 ml. Therefore we recommend an accurate determination of blood loss during resection of larger glands.  相似文献   
996.
A survey based on those employed by Petitpas, Brewer, Rivera, and Van Raalte (1994), Pope, Tabachnick, and Keith-Spiegel (1987), Pope and Vetter (1992), and Tabachnick, Keith-Spiegel, and Pope (1991) was used to investigate the ethical beliefs and behaviours of Victorian fitness professionals. Although there is evidence that Victorian fitness professionals are knowledgeable about some general ethical principles, the results of this study suggest that there is some lack of consensus among Victorian fitness professionals about the ethical appropriateness of a number of complex issues relating to business practices, confidentiality, dual relationships, and personal and professional boundaries. The findings suggest there is a need to improve the professional and ethical education of fitness professionals and to develop comprehensive ethical principles and a code of conduct that is relevant to the individuals working in the Australian fitness profession.  相似文献   
997.
998.
OBJECTIVE: To investigate the effects of estrogen and progesterone on sleep in postmenopausal women. METHOD: The 33 participants were randomly assigned to an estrogen or placebo group after undergoing clinical and hormonal assessments and a polysomnogram, and they underwent the same tests again after 12 weeks. Then, while still taking estrogen or placebo, they all received progesterone for another 12 weeks and underwent a final polysomnogram. RESULTS: Estrogen plus progesterone was more effective than estrogen alone in decreasing the prevalence of periodic limb movement (PLM) (8.1% vs 2.8%), hot flashes (14.2% vs 0%), and bruxism (11.1% vs 0%) at night, or somnolence and attention difficulty during the day. The prevalences of breathing irregularities, arousal from sleep, anxiety, and memory impairment were decreased in both groups following progesterone treatment. CONCLUSION: While not significantly affecting sleep quality, hormone therapy decreased the prevalence of arousal in both groups and that of PLM in the group treated with estrogen plus progesterone.  相似文献   
999.
1000.
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