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951.
Corneal epithelial permeability for fluorescein was determined after provocation by a local anesthetic in 18 non-insulin-dependent diabetes mellitus (NIDDM) patients, 23 insulin-dependent diabetes mellitus (IDDM) patients, and 22 healthy controls to evaluate the corneal epithelial barrier function in diabetes. All volunteers had Oxybuprocaine instilled into one eye and saline into the other eye. The epithelial permeability values were determined by fluorophotometry, and the ratio between both eyes was calculated for each individual. The mean permeability values of the saline-instilled eyes in the diabetic patients did not differ significantly from those in the healthy controls (P greater than 0.2). The individual ratios between Oxybuprocaine- and saline-instilled eyes in the NIDDM and IDDM patients differed significantly from those in the healthy controls (mean ratios: 2.6, 1.9, and 1.0, respectively; P less than 0.002). The permeability ratios and the percentage glycosylated hemoglobin (HbAlc) were linearly correlated in the NIDDM patients but not in the IDDM patients (r = 0.73, P less than 0.001, and r = 0.09, P greater than 0.68, respectively). The results showed that the corneal epithelial barrier function in the diabetic patients was not impaired compared with that in the healthy controls. After provocation by a local anesthetic, the barrier function was impaired in the diabetic patients only.  相似文献   
952.
An open, multi-centre, general practice study was carried out in 1661 asthmatic patients to assess the efficacy, in terms of symptom relief and changes in lifestyle, of budesonide and to record objective lung function changes and any adverse events. After a 1-week run-in period on any pre-trial anti-asthma medication, patients received either 200 micrograms or 400 micrograms budesonide twice daily by metered dose inhaler for 4 weeks. Peak expiratory flow rate (PEFR) was measured by the doctor on entry, after the run-in, and at the end of the study and patients were asked to complete diary cards on a daily basis to record compliance, bronchodilator usage and the severity of cough, wheeze and sleep disturbance, and weekly to record 5 lifestyle assessments, e.g. physical activity. Analysis of data from the clinic visits and 1375 completed diary cards showed that PEFR increased significantly from 321 +/- 3 l/min at the end of the run-in to 368 +/- 3 l/min at the end of the trial; 77% of patients had an improved PEFR. Bronchodilator use decreased significantly from 4.2 +/- 0.1 times/day during the run-in period to 3.0 +/- 0.1 times/day at the end of the study; 65% of patients used less bronchodilator. Significant improvements were recorded in all the symptoms and lifestyle indices monitored; 76% of patients improved in at least 5 of the 11 assessments. Treatment-emergent adverse events occurred in 103 (6%) of patients: none was classified as serious or unexpected. No sub-group of patients was identified in which the results were at variance from the full sample. It is concluded that budesonide improves patients' lifestyle and ability to carry out normal activities, as well as improving PEFR and reducing bronchodilator use, in mild to moderately severe asthmatics treated in general practice.  相似文献   
953.
Desferrioxamine (DFO) metabolism and its pharmacokinetics were studied in a swine model using high-performance liquid chromatography. DFO and three iron-binding metabolites occurred in plasma. Interindividual differences in pharmacokinetics and metabolism were observed. Urine analysis in 4 pigs showed three iron-binding metabolites. The mean percent dose excreted in urine in the form of the parent drug was 45 +/- 10% and 10 +/- 2% (means +/- SD) in the form of metabolites. Of the total amount of the parent drug infused, 3 h after initiation, 87% was in the form of DFO, whereas 13% was present as the DFO-iron III complex which represented 45 mg of urinary iron elimination. The described DFO infusion protocol provides for sufficient DFO to chelate significant amounts of ferric iron in excess of normal levels, thus allowing experimental studies of iron chelation in a variety of disease states.  相似文献   
954.
955.
In the present study, chlorogenic acid (CGA) isolated from Anthocephalus cadamba was screened for hepatoprotective activity by in vitro and in vivo assay methods using carbon tetrachloride (CCl4) as a model of liver injury. Intraperitoneal administration of CGA to mice at a dose of 100 mg/kg body weight for 8 days caused significant reversal in lipid peroxidation, enzymatic leakage, cytochrome P450 (Cyt P450) inactivation and produced enhancement of cellular antioxidant defence in CCl4-intoxicated mice, revealing that the antioxidative action of CGA is responsible for its liver protective activity. CGA exhibited a better therapeutic protective action than silymarin (SM), in CCl4-administered mice.  相似文献   
956.
3β-hydroxysteroid dehydrogenase/Δ5−Δ4isomerase (3β-HSD) activity was measured in primary dissociated cell cultures prepared from telencephalons of developing zebra finches. 3β-HSD activity was confirmed after cultures were incubated with [7-3H]pregneno- lone (Preg) or (1,2,6,7-3H-) dehydroepiandrosterone (DHEA) and3H-progesterone (Prog) and3H-androstenedione (AE) were detected in the medium. Product identity was confirmed by recrystallizations and by HPLC analysis. When DHEA was used as substrate,3H-estradiol and3H-estrone were also detected in the culture medium, presumably derived from the aromatization of3H-AE or3H-T produced from3H-DHEA. To test this idea, cultures were incubated with3H-DHEA together with radioinert AE or with fadrozole HCl, a potent and specific aromatase inhibitor. In the presence of radioinert AE,3H-AE increased but metabolites of3H-AE decreased in the media; in the presence of fadrozole,3H-estrogens decreased but3H-AE and its androgenic metabolite3H-5β-androstanedione increased. These data demonstrate 3β-HSD activity in the songbird brain. The presence of Prog and estradiol in these cultures suggest that Preg and DHEA can potentially serve as substrates for the ultimate formation of active sex steroids in the songbird telencephalon.  相似文献   
957.
P. Abimelec  M.D.    M. Rybojad  M.D.    S. Cambiaghi  M.D.    I. Moraillon  M.D.    B. Cavelier-Balloy  M.D.    C. Marx  M.D.    P. Morel  M.D. 《Pediatric dermatology》1995,12(4):340-342
Abstract: The postpubertal appearance of subungual, painful keratotic tumors is a rare feature of incontinentia pigmenti. A patient affected by incontinentia pigmenti developed subungual, painful, nontumoral, hyperkeratotic lesions of the hands at 10 years of age. The mildness of the subungual lesions may be explained by the early stage of the disorder, but it is difficult to correlate the severity of the fingertip pain with the absence of true tumoral swelling. To our knowledge this is the youngest patient reported so far and the only one with a prepubertal expression of this puzzling disorder.  相似文献   
958.
Critical to the proper management of pyoderma gangrenosum are correct diagnosis, identification and treatment of any underlying disorder, and the proper choice of topical and systemic therapy. Many agents are available for the treatment of pyoderma gangrenosum. We review the current therapeutic options, their efficacy and side effects, and we offer some guidelines for their proper selection.  相似文献   
959.
PURPOSETo investigate the decrease in signal intensity on T1 - weighted MR images of some hemorrhagic intracranial lesions after administration of contrast material.METHODSPostprocessing digital image subtraction was performed in 16 MR studies (13 patients) of lesions that showed hyperintensity on noncontrast T1-weighted images. Repetition time and echo time were identical for all precontrast and postcontrast studies. Regions of interest were measured in each lesion, contralateral white matter, and background (before and after contrast enhancement).RESULTSIn six of 16 MR studies, a significant net decrease in signal intensity was seen within the hemorrhagic lesion after contrast enhancement (reverse enhancement). All the lesions were hematomas within residual or recurrent malignant tumors.CONCLUSIONSDigital image subtraction confirms the existence of reverse enhancement. This phenomenon is due to the combined T2-shortening effects of two paramagnetic substances, methemoglobin and gadolinium, which cause the signal reduction produced by the T2 effects to occur at lower concentrations of gadolinium.  相似文献   
960.
The synthesis of nerve growth factor (NGF) by the hippocampus raises the possibility that NGF may play a role in the regulation of the hypothalamic-pituitary-adrenal axis (HPAA). Subchronic cold stress has been shown to activate the HPAA in a mild noninvasive manner, to stimulate serum glucocorticoid levels, and to perturb NGF binding in hippocampus and basal forebrain. One or repeated episodes of cold stress increased NGF mRNA levels in the hippocampus and p75NGFR mRNA levels in the basal forebrain. These changes were not due to elevated serum glucocorticoid levels since treatment with exogenous corticosterone had no effect on NGF and p75NGFR mRNA levels. Adrenalectomy did not prevent the stress induced increases in NGF and p75NGFR mRNA. © 1993 Wiley-Liss, Inc.  相似文献   
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