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Benign noninflammatory bronchial stenosis: treatment with balloon dilation   总被引:11,自引:0,他引:11  
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Elevation of prostaglandins and protein in the aqueous humor is an immediate response to Yag-laser anterior capsulotomy. There was a significant correlation between prostaglandins and thromboxane to the elevation of intraocular pressure. The elevation of protein concentration was proportional to the elevation of prostaglandin F1, but not to thromboxane. The biochemical changes in the aqueous humor were more severe as laser power was increased above 3 mj. While the role of prostaglandins in the elevation of intraocular pressure is uncertain, the present data recommend the selection of laser power below 3 mj to avoid pressure rise instead of inhibition of all prostaglandin synthesis by medication.  相似文献   
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Glucocorticoids (GCs, cortisol in human) are associated with impairments in declarative memory retrieval. Brain regions hypothesized to mediate these effects are the hippocampus and prefrontal cortex (PFC). Our aim was to use fMRI in localizing the effects of GCs during declarative memory retrieval. Therefore, we tested memory retrieval in 21 young healthy males in a randomized placebo-controlled crossover design. Participants encoded word lists containing neutral and emotional words 1 h prior to ingestion of 20 mg hydrocortisone. Memory retrieval was tested using an old/new recognition paradigm in a rapid event-related design. It was found that hydrocortisone decreased brain activity in both the hippocampus and PFC during successful retrieval of neutral words. These observations are consistent with previous animal and human studies suggesting that glucocorticoids modulate both hippocampal and prefrontal brain regions that are crucially involved in memory processing. Electronic Supplementary Material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
6.
Muscle biopsies were taken from 10 control subjects and five AMP deaminase (AMPD) deficient individuals before and after an ischaemic isometric exercise test and analysed for purine nucleotide, NAD+, creatine phosphate (CP) and lactate content. The decrease of ATP induced by the exercise test was significantly lower in the AMPD deficient patients than in the controls, but the decrease of creatine phosphate and the increase of lactate did not differ. There were no significant differences in the exertional performance level between patients and controls and no evidence was obtained of an increased energy expenditure per unit of performance in AMPD deficiency. The AMPD deficient individuals were equally capable of maintaining a high adenylate energy charge (EC) as the control subjects, which indicates a normal regulation of the balance between ATP consumption and ATP regeneration. ATP, ADP and total adenine nucleotide (TAN) but not AMP, were significantly elevated in the AMPD deficient patients as compared with the controls before as well as after the exercise test. This underlines the role of AMPD activity in the adenine nucleotide catabolism of skeletal muscle.  相似文献   
7.
Scintigraphy with 123I-Tyr-3-octreotide has several major drawbacks as regards its metabolic behavior, its cumbersome preparation and the short physical half-life of the radionuclide. The use of another radiolabeled analog of somatostatin, 111In-DTPA-D-Phe-1-octreotide, has consequently been proposed. DTPA-D-Phe-1-octreotide can be radiolabeled with 111In in an easy single-step procedure. DTPA-D-Phe-1-octreotide is cleared predominantly via the kidneys. Fecal excretion of radioactivity amounts to only a few percent of the administered radioactivity. For the radiation dose to normal tissues, the most important organs are the kidneys, the spleen, the urinary bladder, the liver and the remainder of the body. The calculated effective dose equivalent is 0.08 mSv/MBq. Optimal 111In-DTPA-D-Phe-1-octreotide scintigraphic imaging of various somatostatin receptor-positive tumors was obtained 24 hr after injection. In the six patients studied, tumor localization with 123I-Tyr-3-octreotide and with 111In-DTPA-D-Phe-1-octreotide were found to be similar. However, the normal pituitary is more frequently visualized with the latter radiopharmaceutical. In conclusion, 111In-DTPA-D-Phe-1-octreotide appears to be a sensitive somatostatin receptor-positive tissue-seeking radiopharmaceutical with some remarkable advantages: easy preparation, general availability, appropriate half-life and absence of major interference in the upper abdominal region, because of its renal clearance. Therefore, 111In-DTPA-D-Phe-1-octreotide may be suitable for use in SPECT of the abdomen, which is important in the localization of small endocrine gastroenteropancreatic tumors.  相似文献   
8.
Objective. The objective of this clinical study was to define the diagnostic value of plain radiography, digital subtraction arthrography and two-phase bone scintigraphy in patients with clinically loose or infected hip prostheses. Design. Digital subtraction arthrograms, scintigrams and plain radiographs of 70 consecutive patients who underwent revision hip arthroplasty were scored individually and in masked fashion for the presence or absence of features indicating loosening of femoral and/or acetabular components. The operative findings acted as the gold standard. Results. Digital subtraction arthrography was best (P<0.001) for predicting a loose acetabular component, while no significant additional predictive value was found for plain radiographs (P=0.24) and scintigraphy (P=0.27). Digital subtraction arthrography was also the most important modality for predicting a loose femoral component (P=0.001), while the plain radiograph was of significant (P=0.04) additional value and scintigraphy was of no additional value (P=0.13) on multivariate analysis. Conclusion. Digital subtraction arthrography gives the best results in the prediction of loosening of acetabular and femoral components. Plain radiographs give additional information on loosening of the femoral component, but scintigraphy offers no additional advantage.  相似文献   
9.
Using an FT 60 schedule, rats on 100% free feeding tested in the dark phase of a 12:12 light-dark cycle were trained to self-administer ethanol intravenously. The effect was dose-dependent with 20% ethanol being the preferred dose as measured by the number of infusions. Daily administration of 1.5 mg/kg melatonin significantly increased ethanol self-injection in the dark but not in the light. The time of day of testing and/or drug administration may be an important variable in studies on self-administration of drugs. Testing in the dark may eliminate the need for reducing body weight when inducing self-administration of ethanol.  相似文献   
10.
H D Oei 《Annals of allergy》1988,61(6):436-439
In this double-blind study, 65 patients with hay fever were treated for 14 days with either loratadine 10 mg once daily, astemizole 10 mg once daily, or placebo. On the third day of treatment loratadine was statistically superior to placebo, but astemizole and placebo showed no significant differences according to the ratings for symptomatology, efficacy, and individual symptoms. Adverse effects were minimal and did not differ between the three groups. Loratadine had a significantly earlier onset of action than astemizole with comparable efficacy and safety.  相似文献   
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