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991.
PURPOSE: To compare the bioavailability and pupillary effect of flurbiprofen and indomethacin during phacoemulsification and intraocular lens implantation. SETTING: Gimbel Eye Centre, Calgary, Alberta, Canada. METHODS: In this prospective, randomized, double-masked study, 236 patients had cataract extraction by phacoemulsification and posterior chamber intraocular lens implantation. They received topical flurbiprofen 0.03% solution or indomethacin 1% suspension applied every 15 minutes for 60 to 75 minutes before surgery. An aqueous humor sample (100 microL) was taken immediately before the corneal incision was made. Pupil diameters (horizontal and vertical) were measured before aqueous humor sampling, after phacoemulsification, after irrigation and aspiration (I/A), and after acetylcholine instillation. RESULTS: Mean concentration of flurbiprofen and indomethacin in the aqueous humor was 59.8 ng/mL and 90.2 ng/mL, respectively (P < .001). The percentage of dose detected in the aqueous humor was 4.38% in the flurbiprofen group and 0.21% in the indomethacin group (P < .001). Pupil diameters were 7.2 and 7.3 mm presurgery and 7.0 and 7.0 mm after I/A in the flurbiprofen and indomethacin groups, respectively (P > .05). No adverse events were reported in either group. CONCLUSIONS: Although the absolute concentration of indomethacin was higher, the percentage of dose detected in the aqueous humor was 20 times greater in the flurbiprofen than in the indomethacin group. Flurbiprofen is absorbed 20 times more readily than indomethacin. Both drugs were equally effective in preventing miosis during cataract surgery.  相似文献   
992.
This study was designed to focus on the potential stress that xanthine oxidase could produce in copper-deficient rats fed fructose. Fructose consumption results in an excess production of uric acid due to an increased degradation of nucleotides. The enzyme xanthine oxidase catalyzes the oxidation of both hypoxanthine and xanthine. During the oxidation process free radicals are generated, which in turn, induce lipid peroxidation and premature death. Allopurinol -- a competitive inhibitor of xanthine oxidase -- could alleviate the combined effects of fructose feeding and copper deficiency. Twenty-five male rats were fed for 4 weeks from weaning a copper-deficient or adequate diet containing fructose. Twelve rats were given a daily oral dose of 5 mg allopurinol/100 g b.wt. Two copper-deficient rats that were not treated with allopurinol died prematurely during the fourth week of the study. No mortality occurred in the group of copper-deficient rats that had been treated with allopurinol. Anemia was alleviated by allopurinol, which in turn, could be responsible for improved growth rate. Allopurinol was effective in inhibiting xanthine oxidase activity in vivo as measured by the dramatic reduction of uric acid production. Lipid peroxidation, however, was not affected by allopurinol. It is concluded that the beneficial effects of allopurinol in copper deficiency do not appear to be related to prevention of oxygen radicals, but rather, to the protection against the catabolic destruction of purines, which in turn, increases nucleotide pool.  相似文献   
993.
Severe heart failure in acute rheumatic myocarditis is rare. It may be rapidly reversible with treatment, so maximal medical treatment and, if necessary, mechanical support should be given before heart transplantation is considered.  相似文献   
994.
A recombinant baculovirus containing a cDNA clone encoding the nucleocapsid (NP) protein of Newcastle disease virus (strain Ulster 2C) has been used to infect insect cells (Spodoptera frugiperda). High levels of overexpressed NP protein were observed, comprising up to 40% of total cellular protein, which were subsequently shown to be antigenic. Nucleoprotein derived from the crude soluble lysate of infected insect cells has been used in an indirect ELISA to detect the presence of anti-NDV antibodies in a cohort of chicken sera. Data produced from these tests indicated a good correlation between ELISA titre and haemagglutination inhibition test data. The test was not affected by interference from background cellular proteins nor by cross-reactivity with non-NDV poultry pathogens. Additionally, the test did not generate false-positive readings.  相似文献   
995.
A servo-controlled foot platform was used to quantify, in upright stance, the thresholds for sensing ankle inversion and eversion movements in seven geriatric patients with peripheral neuropathy (PN) confirmed by nerve conduction studies and seven age- and gender-matched (C) controls with normal nerve conduction function. The PN group had a 4.6-fold larger (p = 0.0026) threshold (mean [SD] 1.37 [1.74]degrees) for perceiving the presence and direction of an ankle rotation at a 75% rate of success (TH75) than did the C group (0.3[0.17]degrees). Inversion acuity was approximately twice that of eversion acuity in both groups. The PN group demonstrated better proprioceptive acuity in unipedal stance than in bipedal stance, whereas no such difference was found in the C group. Semiquantitative clinical tests of PN group proprioception at the ankle performed in the seated position failed to demonstrate significant differences from controls save in one case; however, the results of such tests at the toe were abnormal in all patients. In the geriatric population, PN is associated with deficits in ankle proprioception known theoretically to hamper maintenance of unipedal balance. It is significant that these deficits are associated with a clinically demonstrable loss of position sense at the toe but not the ankle.  相似文献   
996.
A 57 year-old-man with acute aortic dissection (DeBakey type I) who developed right coronary artery dissection without acute myocardial infarction. He was successful surgically treated and became asymptomatic.  相似文献   
997.
The purpose of our study was to evaluate the regional distribution of the resting cerebral blood flow (CBF) pattern in preterm neonates. Sixty-eight preterm babies with a gestational age of less than 34 weeks and a birth weight of less than 1500 g were enrolled into the study. The CBF was measured by the noninvasive intravenous 133Xenon method at three different times. Depending on the age we classified our measurements into three groups. Group 1: measurement between 2-36 h (n = 46). Group 2: measurement between 36-108 h (n = 39). Group 3: measurement between 108-240 h (n = 41). In all three groups CBF was significantly lower in the occipital region than in the frontal and parietal regions (group 1: frontal region 12.8 +/- 3.5 ml/100 g/min, parietal region 12.8 +/- 3.9 ml/100 mg/min, and occipital region 11.6 +/- 3.18 ml/100 g/min; group 2: frontal region 15.4 +/- 4.2 ml/100 g/min, parietal region 15.3 +/- 4.1 ml/100 g/min, and occipital region 13.4 +/- 3.5 ml/100 g/min; group 3: frontal region 14.6 +/- 3.6 ml/100 g/min, parietal region 14.6 +/- 3.2 ml/100 g/min, and occipital region 12.8 +/- 2.7 ml/100 g/min.). CBF did not differ between the left and the right hemispheres in either of the three measured regions. No gradient was found in infants between 108 h and 240 h of age with periventricular leukomalacia and periventricular haemorrhage. CONCLUSION. In preterm neonates the antero-posterior gradient of CBF is already present. Periventricular leukomalacia as well as periventricular haemorrhage may affect the regional regulation of CBF.  相似文献   
998.
The study was designed to determine whether treatment with an anabolic-androgenic steroid enhances running performance in rats by increasing their freely chosen training distance. Forty male Long-Evans rats were randomly divided into either a sedentary control group or an exercising group caged in specially designed running wheels in which the rats were able to run spontaneously. After 4 wk, both groups were further subdivided into two groups receiving either 0.5-mg Durabolin (nandrolone phenylpropionate) (im) or 0.5-mg saline, every second day. After 8 wk, running distance was similar in both exercising groups. Rats receiving the anabolic-androgenic steroid ran 41% longer during the test of submaximal running endurance compared to the trained rats receiving saline (P < 0.05). Submaximal running endurance was not increased in sedentary rats receiving the anabolic-androgenic steroid. After 4 wk of training, the maximal sprinting speed increased by 29% in trained rats. There was no further increase in maximal sprinting speed after an additional 4 wk of training and treatment with either anabolic-androgenic steroid or saline treatment. Therefore, rats that train spontaneously while being treated with an anabolic-androgenic steroid had increased submaximal running endurance compared with trained rats treated with saline, despite the similar voluntary training distance and skeletal muscle oxidative capacity between the two groups. The mechanism by which treatment with an anabolic-androgenic steroid, combined with training, enhances submaximal running performance could not be identified and needs to be addressed in future studies.  相似文献   
999.
This is a report of a 22-year-old woman with treated anorexia nervosa who died of complications of acute gastric dilatation-that is, infarction and perforation with severe and irreversible shock. Binge eating and drinking, precipitated by emotional crises, contributed to her acute gastric dilatation. This complication of anorexia nervosa has been previously reported, but, unlike the others, this case ended fatally. The literature is reviewed.  相似文献   
1000.
In a multidisciplinary study of risk factors for chronic obstructive pulmonary disease (COPD), a significantly more impairment of forced expiration was observed in ABH nonsecretors than in ABH secretors among 1017 white adults. (ABH refers to the "A" and "B" antigens of the ABO blood group system and "H", the heterogenetic substance which is found in persons of all ABO types including type "O".) Nonsecretors had significantly lower mean values of forced expiratory volume in one second as a percentage of forced vital capacity (FEV1/FVC%) and a significantly larger proportion of them had aberrant values, defined as FEV1/FVC% less than 68. These differences remained when mean values or rates of aberrancy were adjusted for other factors reported to alter risk of airway obstruction. In view of the known COPD-peptic ulcer and nonsecretor-duodenal ulcer associations, these findings suggest that the ability to secrete ABH antigens into secretions of the respiratory and gastrointestinal tract may have a protective effect on epithelialized organs in general, or on the lung and portions of the gut specifically.  相似文献   
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