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981.
982.
983.
Neonatal Graves'' disease.   总被引:1,自引:1,他引:0       下载免费PDF全文
A newborn boy was noted by his mother to have a prominent left eye at birth, but an eye examination was delayed until age 7 months, at which time his ophthalmologist diagnosed exophthalmos. Computed tomography was interpreted as showing mild, diffuse, optic nerve thickening bilaterally suggestive of optic nerve gliomas. Subsequent examination in our clinic revealed pseudoproptosis secondary to retraction of the left upper eyelid. Magnetic resonance imaging demonstrated normal orbital structures. The mother was noted to be clinically hyperthyroid, and abnormal thyroid function tests confirmed the diagnosis. Although the infant was euthyroid, neonatal Graves' ophthalmopathy was diagnosed. He was managed by close observation while his mother was treated for her hyperthyroidism.  相似文献   
984.
The diameter of the temporal superior and inferior retinal artery and vein were measured at the optic disk border and 2 mm from the disk center in 264 nonselected normal eyes on the basis of photographs, with correction of magnification. Additionally, the individual ocular magnification factor was determined by Littmann's method. The mean caliber of the artery was 0.113 +/- 0.019 mm at the disk border and 0.118 +/- 0.023 2 mm from the disk center. The corresponding values for the vein were 0.149 +/- 0.026 mm and 0.159 +/- 0.026 mm. The correlations between vessel caliber and disk size were not significant, but the relationship between disk size and the quotient of vessel diameter divided by disk size was highly significant (p less than 0.0001). Vessel diameter can therefore be taken as an independent unit for determining optic disk size in relative and approximately also in absolute units. Thus, mean horizontal disk diameter (1.77 +/- 0.33 mm) corresponded to 16.3 +/- 3.5 artery and 12.3 +/- 2.6 vein diameters (measured at the optic disk border). The mean individual ocular magnification factor was 0.302 +/- 0.017, with a Gauss standard distribution. If the optical characteristics of a photographed eye are not known and the ocular magnification factor is assumed to be 0.302, then 68.3% of all eyes will be covered with an inaccuracy of 5.6% and 95.5% of all eyes with an inaccuracy of 11.2%.  相似文献   
985.
We examined two patients with unilateral ophthalmologic findings secondary to pansinusitis caused by Bipolaris. Both patients were healthy young men. One patient had a gradual visual loss, whereas the other showed proptosis. Surgical debridement was the primary treatment in both patients. One patient received antifungal therapy, whereas the other was cured with surgery alone.  相似文献   
986.
Methods: The effects of three months of treatment with octreotide on gastric acid hypersecretion induced by hypergastrinaemia were investigated in patients with Zollinger-Ellison syndrome (n= 5) or antral G-cell hyperfunction (n= 4). Gastric acid secretion, fasting plasma gastrin concentrations and clinical findings were examined, and a morphometrical analysis of oxyntic endocrine cells was performed. Results: Administration of octreotide 100 meg b.d. subcutaneously significantly decreased the volume density of argyrophil cells (P < 0.05) as well as basal and pentagastrin-stimulated acid secretion (P < 0.05). Although partial or complete loss of inhibition was found in most patients after 3 months, gastrin levels were decreased during the first 2 months of treatment (P < 0.05). Fundic D-cells were not affected by treatment. Positive correlations were observed between volume density of argyrophil cells and basal acid output (r= 0.65); plasma gastrin and basal acid output (r= 0.74); plasma gastrin concentrations and volume density of argyrophil cells (r= 0.80). Conclusion: These results support the important role of the enterochromamn-like cell in maintaining acid secretion, and indicate a specific role for octreotide in the therapy of gastric acid hypersecretion associated with hypergastrinaemic diseases.  相似文献   
987.
988.
Clarithromycin is known to accumulate in polymorphonuclear leukocytes, but no accumulation studies with macrophages have been reported. We exposed J774 macrophages, grown for 4–6 days, to clarithromycin 3.0 μg/ml for 2 hours. The cells were separated from the extracellular fluid, and the concentration of clarithromycin was determined in an agar diffusion bioassay. The accumulation of clarithromycin was 15.8-fold greater in the cells than it was in the extracellular fluid when the test was performed with noninfected cells, and 17.3-fold greater for cells infected with Mycobacterium avium. However, the ratio was substantially lower, only 3.7 for dead macrophages, suggesting that intracellular accumulation is probably an active process. These data may clarify the nature of the activity of clarithromycin against M. avium in macrophages.  相似文献   
989.
Study Objective . To determine albuterol delivery by metered-dose inhaler (MDI) in an in vitro pediatric mechanical ventilatory circuit model. The influence of a spacing device, endotracheal tube (ETT) diameter and length, and air humidity was also investigated. Design . An albuterol MDI canister was connected to an AeroVent spacer or Airlife MDI adapter and ETT 4.0, 5.0, or 6.0 mm at commercially available and equal lengths. The ETT tip was attached to an in-line filter holder with a 1-μm type A/E glass fiber filter. Ventilator settings were fractional concentration of inspired oxygen 50%, tidal volume 250 ml, inspiratory:expiratory (I:E) ratio 1:3, rate 25 breaths/minute, temperature 35°C, and a decelerating flow pattern. Ten albuterol canisters were activated two times each (total 2000 μg) into dry (4.0-, 5.0-, and 6.0-mm ETT) and humidified air (4.0- and 6.0-mm ETT) and repeated in triplicate. Percentage MDI output was determined by weighing the filter before and after drug administration (balance sensitivity 10 μg). Significant differences (p≤0.05) among the groups with and without a spacer and in dry and humidified air were determined by ANOVA with Scheffe's multiple comparison test. Multiple regression was used to determine significant associations between ETT diameter and length and delivery. Main Results . With the AeroVent spacer in humidified air, delivery with the 4.0- and 6.0-mm ETT was approximately 2.3% and 5%, respectively. The spacer and dry air significantly improved delivery. Conclusions . In humidified air, the dose of albuterol by MDI with an AeroVent spacer should be doubled for children intubated with 6.0-mm ETT, and four puffs administered for every one puff desired for 4.0-mm ETT. The results of this investigation should prove useful in initial clinical trials of albuterol MDI in ventilator-dependent infants and children.  相似文献   
990.
1. Epidermal growth factor is a potent mitogen that causes natriuresis, diuresis and inhibition of arginine vasopressin-induced water reabsorption. 2. The aim of this study was to determine any interaction between epidermal growth factor and the V1 (vascular) and/or V2 (antidiuretic) arginine vasopressin receptor subtypes. 3. Radioligand binding displacement assays demonstrated that although arginine vasopressin related peptides displaced both radioligands from renal medullary membranes at low concentrations epidermal growth factor displaced neither. 4. Arginine vasopressin V2 receptor second messenger cyclic adenosine monophosphate (CAMP) production was inhibited by epidermal growth factor (IC50 2 ± 10?7 mol/L) as was sodium fluoride cAMP production but only at much higher concentrations. 5. Therefore the diuretic effect of epidermal growth factor is not via direct antagonism of arginine vasopressin receptors but seems mediated via inhibition of the V2 second messenger system.  相似文献   
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