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21.
A chimeric dopamine transporter (DAT) cDNA encoding mutant human DAT (hDAT) protein in which the intracellular carboxyl-terminal tail is replaced by that of the bovine dopamine transporter (bDAT) was constructed. The chimeric hDAT cDNA was expressed in COS-7 cells, and [3H]dopamine and [3H]MPP+ uptake and [3H]CFT binding capacities were assessed. Substrate transport and ligand binding of bDAT were reduced by 32-43% as a result of substitution of the carboxyl tail in hDAT, suggesting that the functional characteristics of bDAT arise from differences in the carboxyl tail between human and bovine DAT. Thus, it appears that the sequences encoded within the carboxyl terminal of DAT would be one of the important determinants for its functions.  相似文献   
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To investigate the outcome of Graves' thyrotoxicosis after antithyroid drug management, data from 81 patients, treated in Chang Gung Memorial Hospital at Taipei and Linkou from October 1981 to March 1990, were analyzed. The gender ratio of female to male was 59:22. The mean age of onset was 33.1 +/- 10.5(15-60) year-old. All the patients were treated with antithyroid drug (Thionamide group) for a duration of 11 to 63 months (mean +/- SD = 28.1 +/- 9.8 months). Forty of 81 patients (49.4%) were remained remission after up to 2 years of follow-up. Those patients relapse usually occurred within 2 years after discontinuation of treatment (34/41), and only one exceptional case relapsed after 3 years. Three conditions affected the relapse rate. Patients with larger goiter (grade II-III) and shorter duration of treatment (< 23 months) had a higher relapse rate than those-with smaller goiter (grade O-I) [29/46 vs. 12/35; chi 2 = 6.576, p = 0.010; p = 0.015 in stepwise logistic regression (LR)] and longer duration of treatment (> or = 23 months) (15/20 vs. 26/61; chi 2 = 6.316, p = 0.012; p = 0.020 in LR). Patients with higher pre-treated serum triiodothyronine (T3) level (T3 > or = 300 ng/dl) had a higher relapse rate than those with lower T3 level (T3 < 300 ng/dl) in univariate analysis (30/50 vs. 11/31, chi 2 = 4.601, p = 0.032), but no significant difference by LR (P = 0.094). Other clinical parameters including age, sex, past history, family history, thyroxine (T4) level, T3/T4 ratio, thyroid autoantibodies, staging of ophthalmopathy, responsiveness to thyrotropin-releasing hormone stimulation test at the end of treatment, and whether combined treatment with thyroxine had no significant difference between the relapse and remission groups. These data suggest: (a) patients with larger goiter (grade II-III had higher relapse rate; (b) most of the recurrent thyrotoxicosis patients relapsed within two years after drug withdrawal; (c) continuing treatment for more than twenty-three months produces better outcome; (d) patients with Graves' thyrotoxicosis should be followed up for at least three years after withdrawal of antithyroid drug.  相似文献   
24.
Responds to the discussion by A. H. Yee et al (see record 1994-09250-001) of A. R. Jensen's (e.g., see record 1986-18910-001) research on racial differences in abilities and states that the references to Jensen's work are dated. Jensen notes more recent research (Jensen and P. A. Whang; see PA, Vol 81:1181 and 20927) and provides an explanation for his research focus on Black–White differences in cognitive abilities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
25.
A novel technique for both online and offline computation is presented. With this technique, a reconstruction analysis in elementary particle physics, otherwise prohibitively long, has been accomplished. It will be used online in an upcoming Fermilab experiment to reconstruct more than 100000 events per second and to trigger on the basis of that information. The technique delivers 40 gigaoperations per second, has a bandwidth on the order of gigabytes per second, and has a modest cost. An overview of the program, details of the system, and performance measurements are presented  相似文献   
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Although multidisciplinary pain programs have been demonstrated to be effective, the processes of improvement have yet to be clarified. Cognitive-behavioral models posit that improvement is due, in part, to changes in patient pain beliefs and coping strategies. To test the relationships between treatment outcome and changes in beliefs and coping strategies, 94 chronic pain patients (aged 21–64 yrs) completed measures of physical and psychological functioning, health care utilization, pain beliefs, and use of pain coping strategies at admission and 3 to 6 mo after inpatient pain treatment. Improved functioning and decreased health care use were associated with changes in both beliefs and cognitive coping strategies. However, changes in some coping strategies, such as exercise and use of rest, were not associated with improvement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
28.
In the case study presented in this paper we consider early development phases of a mechanical product. We want to evaluate different concepts and decide which one(s) to pursue. A problem in early phases is that usually no test runs are available. In our case study, based on a standard, there are ways to compute the lifetime distributions of the components of the different concepts. Some parameters needed for these computations are not known precisely. Unfortunately, the lifetime distributions of the components are highly sensitive to these parameters. Our approach is to equip these parameters with distributions. These distributions would be called prior distributions in Bayesian terminology, but no update is possible since no test runs are available. Our approach implies that the distribution of the system lifetime for each concept is random, i.e. we get random elements in the space of lifetime distributions. Using Monte-Carlo simulations, we demonstrate several ways to compare the random lifetime distributions of the concepts. Some of these comparisons use stochastic orderings. We also introduce a new stochastic ordering which is particularly suitable for reliability purposes. Our case study, consisting of three scenarios, allows us to demonstrate some conclusions that can be reached.  相似文献   
29.
Hypnosis has been demonstrated to reduce analogue pain, and studies on the mechanisms of laboratory pain reduction have provided useful applications to clinical populations. Studies showing central nervous system activity during hypnotic procedures offer preliminary information concerning possible physiological mechanisms of hypnotic analgesia. Randomized controlled studies with clinical populations indicate that hypnosis has a reliable and significant impact on acute procedural pain and chronic pain conditions, Methodological issues of this body of research are discussed, as are methods to better integrate hypnosis into comprehensive pain treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
30.
The antinociceptive effects of morphine (5 micrograms) microinjected into the ventrolateral periaqueductal gray were determined using both the tail flick and the foot withdrawal responses to noxious radiant heating in lightly anesthetized rats. Intrathecal injection of appropriate antagonists was used to determine whether the antinociceptive effects of morphine were mediated by alpha 2-noradrenergic, serotonergic, opioid, or cholinergic muscarinic receptors. The increase in the foot withdrawal response latency produced by microinjection of morphine in the ventrolateral periaqueductal gray was reversed by intrathecal injection of the cholinergic muscarinic receptor antagonist atropine, but was not affected by the alpha 2-adrenoceptor antagonist yohimbine, the serotonergic receptor antagonist methysergide, or the opioid receptor antagonist naloxone. In contrast, the increase in the tail flick response latency produced by morphine was reduced by either yohimbine, methysergide or atropine. These results indicate that microinjection of morphine in the ventrolateral periaqueductal gray inhibits nociceptive responses to noxious heating of the tail by activating descending neuronal systems that are different from those that inhibits the nociceptive responses to noxious heating of the feet. More specifically, serotonergic, muscarinic cholinergic and alpha 2-noradrenergic receptors appear to mediate the antinociception produced by morphine using the tail flick test. In contrast, muscarinic cholinergic, but not monoamine receptors appear to mediate the antinociceptive effects of morphine using the foot withdrawal response.  相似文献   
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