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41.
检测孕妇血浆中的urocortin 总被引:2,自引:0,他引:2
目的:研究urocortin(促肾上腺皮质激素释放激素肽类家族新成员)是否存在于孕妇血循环中及其含量,以证实urocortin是否能在妊娠中产生并由此调节子宫-胎盘的血管张力。方法:用放射免疫测定法从受孕16周起检测孕妇血浆中是否含有urocortin,并用凝胶层析法检测从孕妇血浆中提取的urocortin是否与人工合成的urocortin标准品一致。结果:从受孕16周起孕妇的血浆中即可测得uro 相似文献
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OBJECTIVE: To examine the effect of 17beta-estradiol on the severity of the cardinal signs of PD in postmenopausal women. BACKGROUND: Although the impact of estrogens on the manifestations of PD has not been subjected to rigorous study, their use is generally thought to be associated with a detrimental antidopaminergic effect. METHODS: A double-blind, placebo-controlled, two-arm crossover study of high-dose transdermal 17beta-estradiol was conducted in eight postmenopausal women with mild to moderate PD, all but one of whom exhibited levodopa-induced dyskinesias. Patients were randomized initially to either hormonal treatment or placebo for 2 weeks, followed by a 2-week washout period, and then another 2-week crossover treatment period. Active treatment employed four skin patches each releasing 0.1 mg of estradiol daily, replaced every 2 to 3 days. RESULTS: After 10 days of treatment a significant reduction was observed in the antiparkinsonian threshold dose of IV levodopa. Mean duration and magnitude of the antiparkinsonian response to threshold or high doses of levodopa were unchanged, and dyskinesia scores were unaltered during 17beta-estradiol treatment compared with placebo. No worsening in "on" time or motor ratings with estrogen treatment was documented. CONCLUSIONS: 17beta-estradiol appears to display a slight prodopaminergic (or antiparkinsonian) effect without consistently altering dyskinesias. Standard postmenopausal replacement therapy with transdermal 17beta-estradiol is likely to be well tolerated by many female parkinsonian patients. 相似文献
44.
Effect of dopamine denervation and dopamine agonist administration on serine phosphorylation of striatal NMDA receptor subunits 总被引:8,自引:0,他引:8
Sensitization of striatal N-methyl-d-aspartate (NMDA) receptors has been implicated in the pathogenesis of the response alterations associated with dopaminomimetic treatment of parkinsonian animals and patients. To determine whether serine phosphorylation of NMDA receptor subunits by activation of Ca2+/calmodulin-dependent protein-kinase II (CaMKII) contributes to this process, we examined the effects of unilateral nigrostriatal ablation with 6-hydroxydopamine and subsequent treatment with levodopa, SKF 38393 (D1-preferring dopamine agonist), or quinpirole (D2-preferring agonist) on motor responses and phosphorylation states. Three weeks of twice-daily levodopa administration to rats shortened the duration of their rotational response to levodopa or SKF 38393 challenge, but prolonged the duration of quinpirole-induced rotation. At the same time, levodopa treatment elevated serine phosphorylation of striatal NR2A (p<0.02), but not that of NR2B subunits, without associated changes in subunit protein levels. Chronic treatment with SKF 38393 increased NR2A (p<0.0001) but decreased NR2B (p<0.004) serine phosphorylation. In contrast, chronic quinpirole treatment had no effect on NR2A but increased NR2B phosphorylation (p<0.0001). The acute intrastriatal injection of the CaMKII inhibitor KN93 (1.0 micrograms) not only normalized the levodopa-induced motor response alterations but also attenuated the D1 and D2 receptor-mediated serine phosphorylation of NR2A and NR2B subunits, respectively (p<0.02). These results suggest that a CaMKII-mediated rise in serine phosphorylation of NMDA receptor subunits induced by intermittent stimulation of D1 or D2 dopaminergic receptors contributes to the apparent enhancement in striatal NMDA receptor sensitivity and thus to the dopaminergic response plasticity in levodopa-treated parkinsonian rats. 相似文献
45.
Catherine S. Fichten Rhonda Amsel Kristen Robillard Vicki Tagalakis 《Cognitive therapy and research》1991,15(5):345-369
This study explores three issues: thoughts and feelings of individuals with and without physical disabilities concerning encounters in different situations, ways of grouping self-statements into valenced categories, and use of states-of-mind (SOM) ratios as an alternative to positive and negative thought frequencies. Data from 127 able-bodied and 46 physically disabled college students indicate that, in everyday social encounters, nondisabled individuals' thoughts and feelings were more negative, while those of disabled individuals were more negative when helping was involved and when encounters centered on the impairment. Thus, problematic encounters between people with and without disabilities may be due to the reactions of individuals with disabilities in situations which involve help, and to reactions of able-bodied persons in everyday contexts. The data also confirm the utility of SOM ratios as an alternative to valenced frequencies in cognitive assessment: SOM scores discriminated groups when situational demands were manipulated and scores were linearly related to criterion measures. However, SOM ratios differed dramatically, depending on the attentional focus of thoughts. The findings illustrate types of thoughts which occur during interaction between people with and without disabilities, demonstrate a simple technique for grouping thoughts into valenced categories on an empirical basis, and highlight the relative contribution of cognitive and affective elements to overall valenced scores. Implications for research on assessment of self-statements are discussed and recommendations are made concerning programming to facilitate the social integration of people with disabilities.This research was supported by grants to the first author from the Social Sciences and Humanities Research Council of Canada and from Fonds F.C.A.R. pour l'aide et le soutien à la recherche. Thanks are due to Meribah Aikens, Maria Barile, Leo Bissonette, Bosco Daude, Jim Dubois, Lillian Fox, Evelyn Gold, Naomi Goodz, Darlene Judd, André Leblanc, John Martos, Sue McKenzie, Irwin Slopak, and Joan Wolforth for their assistance with various stages of this investigation. 相似文献
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W.Edward Richards MD Sheila M. Dobin PhD Vicki Malone CLSp Alfred B. Knight MD Thomas J. Kuehl PhD 《American journal of obstetrics and gynecology》1997,176(6):1172-1180
OBJECTIVE: Although most methods for selecting the sex of offspring by sorting spermatozoa are ineffective at shifting the ratio of Y- to X-containing cells, some commercial sources continue to offer such services. Our objective was to evaluate commercially “sorted” samples with use of dual-color fluorescence in situ hybridization and to identify variations in assessment by comparing motile and total sperm populations, donors, observers, and fluorescence in situ hybridization probes.STUDY DESIGN: Cryopreserved sperm from seven anonymous donors were processed as for insemination. Sperm cells from each total sample or motile subfraction were prepared for fluorescence in situ hybridization by incubation with disulfide-reducing agents to expand sperm nuclei. Two sets of X and Y chromosome–specific, fluorophore-labeled deoxyribonucleic acid probes were used. At least 400 nuclei from each preparation were classified independently by three blinded observers. Hybridization efficiency, aneuploidy, and sex chromosome content were evaluated in subsets of five unsorted, five female-oriented, and five male-oriented samples. Total and motile subfractions were compared with eight samples. Fluorescence in situ hybridization probes were compared in five paired unsorted samples.RESULTS: No differences were detected between washed samples and paired motile subfractions. No differences in hybridization and aneuploidy were detected between groups of sorted samples. The Y/X ratio was significantly different between the sorted groups. However, male-oriented samples had a lower Y/X ratio than female-oriented samples did. Observer and probe choice accounted for small but significant variations that did not alter conclusions about the Y/X ratio for sorted samples.CONCLUSION: In a series of 10 sorted samples from one commercial source, dual-color fluorescence in situ hybridization demonstrated a small but significant shift in the sex chromosome ratios among samples. However, this shift was opposite to that expected by the orientation of the sorted samples. (Am J Obstet Gynecol 1997;176:1172-80.) 相似文献
48.
Janet Li Paul Roche Jenean Spencer Ivan Bastian Amanda Christensen Mark Hurwitz Anastasios Konstantinos Vicki Krause Moira McKinnon Avner Misrachi Graham Tallis Justin Waring 《Communicable diseases intelligence》2004,28(4):464-473
The National Notifiable Disease Surveillance System (NNDSS) received 982 tuberculosis (TB) notifications in 2003, of which 947 were new cases, 33 were relapses and two were cases with unknown history. The incidence of TB in Australia has remained at a stable rate since 1985 and was 4.9 cases per 100,000 population in 2003. The high-incidence groups remain people born overseas and Indigenous Australians at 19.9 and 8.7 cases per 100,000 population, respectively. By contrast the incidence in non-Indigenous Australians was 0.9 per 100,000. Comparison of the 2003 TB notification data against the performance indicators set by National Tuberculosis Advisory Committee highlights that enhanced TB control measures should be considered among these high-risk groups. 相似文献
49.
Inflammatory effects of coarse and fine particulate matter in relation to chemical and biological constituents 总被引:12,自引:0,他引:12
Schins RP Lightbody JH Borm PJ Shi T Donaldson K Stone V 《Toxicology and applied pharmacology》2004,195(1):1-11
There is conflicting evidence in the literature as to the predominant mechanism and also the compositional element(s) that drives the pulmonary inflammatory response of ambient particulate matter (PM). We have investigated the inflammogenic potential of coarse (2.5-10 microm) and fine (<2.5 microm) PM from both a rural and an industrial location in Germany, using bronchoalveolar lavage (BAL) of rat lungs 18 h post intratracheal instillation with PM. Irrespective of the sampling location, the coarse fraction of PM(10) but not its fine counterpart caused neutrophilic inflammation in rat lungs, in the absence of any severe pulmonary toxicity as indicated by the lack of an increase in lavage protein and lactate dehydrogenase levels. The rural sample of coarse PM also caused a significant increase in the tumor necrosis factor alpha (TNFalpha) content as well as glutathione depletion in the BAL fluid. The contrasting inflammatory responses of the different samples could not be explained by differences in the concentrations of soluble Fe, Cu, V, Ni, Cr, or Al or by the.OH generating capacities of the PM suspensions. However, the effects of the different PM samples were clearly associated with their endotoxin content, as well as their ability to induce interleukin (IL)-8 and TNFalpha from whole blood in vitro. In conclusion, on an equal mass basis, coarse but not fine PM samples from our sampling campaign induced an inflammatory reaction in the lung in the absence of gross cellular lung damage, following intratracheal instillation. Our data also indicate, in accordance with previous independent in vitro observations, that endotoxin or related contaminants may play a role in these in vivo effects. 相似文献
50.