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61.
Free plasma catecholamines were measured by means of a standardized HPLC method in 41 adult patients with severe atopic eczema and in 18 healthy volunteers. The circulating norepinephrine levels were significantly higher in the atopic group (P less than 0.005), by contrast only slight differences were found in the epinephrine and dopamine concentrations. The possible mechanisms leading to these changes at concomitant normal DBH activities are discussed. 相似文献
62.
Organization of dopamine D1 and D2 receptors in human striatum: receptor autoradiographic studies in Huntington's disease and schizophrenia 总被引:3,自引:0,他引:3
The technique of quantitative autoradiography was used to examine the effects of Huntington's disease (HD) and schizophrenia on the organization of striatal dopamine (DA) D1 and D2 receptors. Whereas the striatum of HD cases showed a reduction in the density of D1 ([3H]SCH 23390) and D2 ([3H]spiroperidol) receptors, the patterning of D2 receptor loss did not match that of the D1 receptor loss. The HD loss of D1 D1 receptors (65%) is far greater than the loss of D2 receptors (28%). Whereas there was a dorsal-ventral gradient of effect on both receptor subtypes, the effects of HD on D2 receptors in the ventral putamen (PUT) and nucleus accumben septi (NAS) were minimal. Similarly, muscarinic M1 and M2 receptors demonstrate different patterns of alteration in HD. The M2 subtype, labeled with [3H]N-methylscopolamine (in the presence of excess pirenzepine to occlude M1 sites), was depleted far more than the M1 receptor subtype, labeled with [3H]pirenzepine. Although the effects of HD on [3H]mazindol labeling of DA terminals were more heterogeneous, there appeared to be a relative preservation of this afferent input to the striatum of the HD cases. In the schizophrenic cases, our autoradiographic studies confirm previous reports of an elevation of D2 receptor density in the striata of many schizophrenics. This increase was evident even though two of the three cases were known to have not been treated with neuroleptics, and the third case may also have been drug naive. However, the increase was far greater in the NAS (164%) and ventral PUT (173%) than more dorsally in the striatum (68%). The density of D1 receptors and DA terminals labeled with [3H]mazindol in the striatum of schizophrenics was not significantly different from that of control cases. Thus in both HD and schizophrenia, the ratio of D2/D1 receptors is altered in favor of the D2 population, particularly in the NAS. 相似文献
63.
《Journal of labelled compounds & radiopharmaceuticals》2006,49(8):707-732
Results are reported on the regioselective C‐deuteriation of 2‐methyl‐tetralone using a series of D‐sources and tertiary amines as potential mediators. The results presented further aid the understanding of kinetic deuteriation of both ‘base‐containing’ and ‘base‐free’ enolates. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
64.
K. Nakamura T. Saito T. Nishiwaki K. Ueno M. Nashimoto Y. Okuda Y. Tsuchiya R. Oshiki K. Muto M. Yamamoto 《Osteoporosis international》2006,17(8):1202-1207
Introduction A few epidemiologic studies have comprehensively attempted to identify risk factors for low bone mineral density (BMD) in elderly Asian women. The purpose of this study was to identify demographic, lifestyle, and biochemical factors correlated with BMD in elderly Japanese women 69 years of age and over.Methods The study design was cross-sectional. The subjects were 583 ambulatory women aged 69 years and over, and their average age was 74.3 (SD 4.4) years. Predictor variables were age, reproductive history, anthropometric indices, grip strength, calcium intake, lifestyle information, and serum 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D (1,25(OH)2D), osteocalcin (OC), and undercarboxylated osteocalcin (ucOC) values. The outcome variable was forearm BMD measured with a DTX-200 osteometer.Results Simple linear regression analyses showed that BMD was significantly positively associated with body height, weight, body mass index, grip strength, serum albumin concentration, and “housework,” and negatively associated with age, years since menopause, age at menarche, number of children, serum 1,25(OH)2D concentration, serum OC concentration, and ucOC concentration. The stepwise multiple regression analysis showed that weight (β=0.00316, SE=0.00028, R2=0.180), age (β=−0.00321, SE=0.00050, R2=0.108), log-transformed serum OC (β=−0.0445, SE=0.0064, R2=0.053), log-transformed serum 1,25(OH)2D (β=−0.0401, SE=0.0074, R2=0.050), “farmwork” (β=0.00904, SE=0.00426, R2=0.005), and serum 25(OH)D concentration (β=0.000281, SE=0.000120, R2=0.003) were significantly associated with BMD.Conclusion It was concluded that body weight is a major predictor of forearm BMD among the factors measured in this study in independent Japanese women 69 years of age and over and that serum 1,25(OH)2D concentration may be associated with cortical BMD. Maintenance of body weight is very important for maintaining BMD in this population, unless a large weight aggravates obesity-related diseases. A follow-up study is needed to confirm these findings. 相似文献
65.
The effects of withdrawal from continuous administration of cocaine on behavioral sensitivity to apomorphine and monoamine receptor density were examined in rats. Subdermal minipumps that delivered either saline or 20 mg/kg/day cocaine hydrochloride were implanted for 2 weeks. Apomorphine-induced stereotypy (0.5 mg/kg, SC) was examined in separate groups of rats either 4 hr or 7, 28, or 60 days after removal of the minipumps. Transient enhanced sensitivity to apomorphine-induced stereotypy occurred during the course of withdrawal. Animals withdrawn from cocaine for 4 hours did not differ from controls in their sensitivity to apomorphine, whereas animals withdrawn from cocaine for 7 days exhibited an increase in apomorphine-induced oral stereotypy relative to controls. However, the enhanced stereotypy response was no longer evident in animals withdrawn for 28–60 days. The animals were sacrificed after behavioral testing, and their brains were assayed for changes in monoamine receptor density in the frontal cortex, caudate-putamen, and nucleus accumbens. The density of 3H-SCH-23390-labeled D1 receptors was altered in all three regions examined in a time-dependent manner that paralleled the changes in behavioral sensitivity to apomorphine. There was a transient decrease in D1 receptor density that was evident by 7 days following withdrawal from continuous cocaine administration and was no longer evident 28 or 60 days posttreatment. There were no changes in 3H-spiroperidol-labeled D2 receptors, 125-pindolol-labeled β-adrenergic receptors, or 3H-ketanserin-labeled 5-HT2 receptors in any of the regions examined at both 4 hr and 7 days after termination of the cocaine infusion. These findings are discussed in terms of their relevance to developing pharmacologic treatments for withdrawal from cocaine. © 1994 Wiley-Liss, Inc. 相似文献
66.
Dr. Gerold Wetscher MD Elizabeth Redmond MD Christine Watfah MD Galen Perdikis MD Michael Gadenstätter MD Rudolph Pointner MD 《Digestive diseases and sciences》1994,39(12):2511-2515
Bone disorders following gastrectomy were studied by measuring absolute and relative bone mineral density of the Wards triangle, serum 1,25-(OH)2-D, alkaline phosphatase, and total serum calcium. The subjects were 20 males who had undergone total gastrectomy not more than three months previously (group A1). Seventeen of these patients were reviewed three years later (group A2). Absolute and relative bone density were significantly lower in group A2 than in A1 (0.52 ± 0.011 g/cm2 versus 0.6 ± 0.014 g/cm2,P<0.01 and 85.5 ± 1.4% age-matched control versus 95 ± 1.3%,P<0.01). 1,25-(OH)2-D was significantly lower in group A2 than in group A1 (14.3 ± 0.97 pg/ml versus 20.6 ± 1.02 pg/ml,P<0.01). There was no difference in alkaline phosphatase and calcium serum concentration. The mean weight loss was 6.26 ± 0.57% over the follow-up period, and weight loss correlated with absolute and relative bone density (r=–0.74,P<0.01). There was a positive correlation between 1,25-(OH)2-D and absolute or relative bone density (r=0.67,r=0.62 andP<0.01). These data suggest that bone density decrease has already occurred three years after total gastrectomy and is positively correlated to 1,25-(OH)2-D deficiency. As no differences in serum alkaline phosphatase and serum calcium concentration were found, these factors are of little value for the early detection of postgastrectomy bone disorders, whereas weight loss is a valuable screening parameter. 相似文献
67.
Macran S. Kind P. Collingwood J. Hull R. McDonald I. Parkinson L. 《Quality of life research》2003,12(2):177-188
This study reports on the preliminary testing of a new measure designed for use alongside EQ-5D in evaluating outcomes in podiatry: the Podiatry Health Questionnaire (PHQ). Individuals aged 18 years or more, receiving podiatry services in clinic or domicilliary locations across four NHS Trusts in Yorkshire and Humberside UK took part in a questionnaire survey. Respondents reported high levels of problems on all six PHQ dimensions. Correlations suggested that the PHQ and EQ-5D were measuring distinct constructs. The levels on each dimension were well defined in terms of self-rated morbidity on the PHQ visual analogue scale (PHQvas) and the EQ-5Dvas, although PHQvas appeared to be slightly more sensitive to changes in health on the dimensions. There was a strong relationship between clinicians' Podiatry Clinical Score rating and reported symptoms for four out of six PHQ dimensions and PHQvas. The PHQ was able to distinguish respondents in terms of their self-reported morbidity in EQ-5D and in terms of their morbidity as assessed by clinicians. It is suggested that the respondent completed PHQ appears to be a useful new measure for assessing foot-related health. However, further investigation of the psychometric properties of the measure is required. 相似文献
68.
69.
BACKGROUND: The purpose of this study was to determine bone mineral density (BMD) of lumbar spine in malnourished children without rachitic manifestations, before and after dietary treatment and vitamin D supplementation, and to compare with healthy children of the same community. METHODS: The subjects were 41 children with malnutrition and 21 healthy controls. None of the children had clinical, biochemical and/or radiological rickets features. The patients had moderate 15 and severe 26 malnutrition according to Gomez's criteria. Using the Wellcome Classification, marasmus was diagnosed in 16 children, kwashiorkor in 10 children. The children with malnutrition were given vitamin D supplementation. RESULTS: BMD was lower in children with malnutrition than in controls (P < 0.01). Mineralization significantly effected the severity of malnutrition (P < 0.01). BMD in kwashiorkor was similar to that of marasmus. The mean BMD level of infants receiving 400 IU of vitamin D daily was similar to that of infants receiving 800 IU of vitamin D daily at the beginning of treatment. In two supplementation groups, the BMD gradually increased during the first 3 months of treatment, but this increase in the infants receiving 800 IU of vitamin D daily was significantly higher than that in the infants receiving 400 IU of vitamin D daily. CONCLUSION: Measurements of BMD in children with malnutrition, especially severe malnutrition, are to be recommended in the initial assessment of the severity of osteopenia and in the follow up to monitor the response to therapy. Children with malnutrition should be given 800 IU of vitamin D daily. The loss of BMD must be accepted as a complication of malnutrition. 相似文献
70.
Mivazerol is a new and selective α2-adrenoceptor agonist which has demonstrated anti-ischemic effects, both in animals and in patients with myocardial ischemia. In the present study, mivazerol was evaluated for its ability to inhibit the release of catecholamines and serotonin (5-HT) in the hippocampus of freely moving rats, and also was compared to clonidine. In vivo microdialysis in combination with high-performance liquid chromatography (HPLC) was employed. Intravenous administration of mivazerol (8.0 μg/kg) had no effect on basal outflow of norepinephrine (NE), dopamine (DA) and 3,4-dihydroxyphenylacetic acid (DOPAC). In contrast, clonidine (8.5 μg/kg, i.v.) attenuated the basal release of DOPAC, which has been proposed to reflect NE biosynthesis, suggesting that clonidine has an inhibitory effect on NE synthesis. In addition, both mivazerol and clonidine decreased the spontaneous release of 5-HT, which provided further evidence that α2-adrenoceptors in the hippocampus modulate 5-HT. Sixty-min immobilization stress significantly increased the release of NE (177 ± 28%), DA (209 ± 46%) and DOPAC (337 ± 72%). Mivazerol (2.5, 8.0 and 25 μg/kg, i.v.) completely prevented the immobilization stress-induced enhancement of NE, DA and DOPAC, which was equi-effective to clonidine at a dose of 8.5 gmg/kg, i.v. These findings demonstrate that mivazerol has a profound modulatory effect on stress-induced neurotransmitter release in the hippocampus, at dose levels reported to protect against myocardial ischemia. 相似文献