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951.
The content of rhodopsin in the eyes of 15 donors (30 eyes) was determined. Both retinal and pigment epithelial fractions were collected from each globe, extracted using 1% CTAB, and the rhodopsin difference spectrum of each fraction was obtained separately. The total amount of rhodopsin, obtained by summing the amounts recovered from the retinal and PE fractions, ranged from 2.00 to 11.94 (median: 6.40) nmoles/eye. Previously reported mean values of about 3.5 to 4.0 nmoles per retina have been obtained using a variety of methods. The present higher values, perhaps largely dependent on procedural details described herein, appear plausible given the known concentrations of rhodopsin in rod outer segments, rod outer segment volumes, and number of rods in the human retina.  相似文献   
952.
Inequalities in mortality between social classes or socioeconomic groups were compared in three European countries, using similar sources of data from large national cohort studies. People registered at a census in 1971 (1975 for France) or a sample of them, were followed until 1980 or 1981. The Gini coefficient, a measure widely used in economics, allowed the comparison of various situations involving different numbers and group sizes. It was applied to age groups 35-44, and 45-54 for men only. According to this measure, inequalities were of the same order in England and Wales and Finland, and greater in France. Differences between the three countries concerning the principal causes of death leading to inequalities were cardiovascular diseases in England and Wales, accidents and cardiovascular diseases in Finland, and cancer and cirrhosis in France.  相似文献   
953.
The purpose of this pilot study was to investigate the metabolic effects of growth hormone (GH) (Humatrope, Eli Lilly & Co., Indianapolis, IN) administration in postoperative (PO) patients receiving peripheral vein nutrition. Seven, well-nourished, nondiabetic patients undergoing elective surgical procedures were given either no drug (n = 3), GH 30 micrograms/kg/day (n = 2), or GH 60 micrograms/kg/day (n = 2) sub-Q daily until eating, up to 7 days PO. All the patients received 5% dextrose with electrolytes in the first 24 hours PO and then received calories at 80 +/- 5% of the measured resting energy expenditure (REE) and amino acid at 1 g/kg/day with electrolytes, vitamins, and minerals. There were no significant outcome differences between the 30 and 60 micrograms/kg/day groups and, therefore, these groups were analyzed together (n = 4). By day 6 of the study, the GH group had a significant reduction in the respiratory quotient (RQ) measured by indirect calorimetry; an increase in nitrogen retention; an increase in plasma transferrin concentrations; and an increase in plasma insulinlike growth factor (IGF1) concentration. There was no increase in blood glucose concentrations, or decrease in urinary 3-methylhistidine excretion; and no adverse effects occurred. We concluded that GH in PO patients on hypocaloric nutrition promoted protein synthesis, fat oxidation, and nitrogen retention. Effective parenteral nutritional support in postoperative adult patients can be achieved without the use of central vein access.  相似文献   
954.
Direct activation of G proteins   总被引:1,自引:0,他引:1  
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955.
Summary A double-blind, placebo-controlled study has been made of the analgesic and respiratory effects of constant rate infusions of meptazinol and morphine in 30 patients after abdominal surgery. Group I received meptazinol, loading dose 50 mg followed by i.v. infusion 0.5 mg · kg−1 · h−1, Group II received morphine, loading dose 5 mg and then an infusion of 0.05 mg · kg−1 · h−1, and Group III received saline. After recovery from inhalation anaesthesia (without opiates or a local anaesthetic) pain relief and chemoreceptor carbon dioxide tolerance were assessed before and at various times after starting the analgesic infusion. A similar degree of pain relief was found after 10 min in Groups I and II, which lasted until the end of observation period (20 h). Heart rate and systolic and diastolic blood pressures were lower in Group II than in Groups I and III, and respiratory rate fell in Groups I and II. After 6 h arterial carbon dioxide tensions (PaCO2) became significantly higher in Group II than Group III. The maximum percentage fall in mean tidal volume (VT) and expired minute volume (0VE) from the preinjection values was significant in Groups I and II. End-tidal carbon-dioxide (PETCO2) and PaCO2 were significantly higher after 20 h of infusion in Group II compared to Group I. The slope of 0VE/PETCO2 (<S>) was increased in Group I and it was significantly reduced in Group II. Analysis of derived variables, such as the CO2 intercept (CO2I) and minute ventilation at 7 kPa (0VE7), indicated a shift to the right of the slopes in Groups I and II, initially more so in Group I. It is concluded that constant rate infusions of meptazinol and morphine were effective in providing postoperative pain relief. However, their effects on the central regulation of respiration were different, as meptazinol did not impair CO2 sensitivity whereas morphine did.  相似文献   
956.
We report on 7 patients (6 M, 1 F) with Coffin-Lowry syndrome who have a sensorineural hearing deficit in addition to developmental delay and characteristic facial changes. One of the patients also had a history of premature exfoliation of primary teeth. These are previously unappreciated clinical signs that may aid in the early diagnosis of Coffin-Lowry syndrome. Early diagnosis and recognition of a hearing deficit in the patient can lead to the use of hearing aids to help the patient achieve his or her full potential. These “;new”; clinical manifestations expand the phenotype of Coffin-Lowry syndrome and constitute an additional indication of pleiotropy. © 1993 Wiley-Liss, Inc.  相似文献   
957.
958.
Pseudomembranous colitis is not a rare complication of antibiotic therapy. 2000 surgical procedures with implantation of grafts in the aorto-iliac region were performed from 1974 through 1988; during this period 11 cases of CMP were observed. The Authors report their experience in regard to the various antibiotics administered.  相似文献   
959.
The involuntary hospitalisation of psychiatric patients continues to be a controversial issue. All patients certified and admitted to Sterkfontein Hospital under Sections 9 and 12 of the Mental Health Act, No. 18 of 1973, over a 4-week period were surveyed. Almost 40% were admitted as urgent certifications. The majority of the patients in the sample were black, single, urban and had either primary or limited high school education. Most patients had been referred from academic/teaching and provincial hospitals. The average duration of hospital stay was 7.2 weeks, with only 1 patient eventually being transferred to a ward for chronic patients within the hospital, which suggests that Sterkfontein Hospital functions largely as an acute psychiatric facility. There was a discrepancy of approximately 30% between the assessments of the certifying and ward doctors, probably as a result of differing uses of terminology. Not only are more community psychiatric services needed, but communication between psychiatry and the other medical disciplines should be improved.  相似文献   
960.
Type IIIC tibial fractures are complex injuries involving extensive bone and soft-tissue devascularization that result in a high percentage of complications and ultimate amputation. An emergency free flap transfer not only may salvage the limb but also may improve the aesthetic and functional results of reconstruction by placing the injured structures in a well-vascularized bed. Two cases of type IIIC tibial fracture were treated in this manner, and we present our experience with a 30-month follow-up of one patient and a 6-month follow-up of another patient.  相似文献   
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