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91.
The time and dose-dependent effects of the in vivo administration of hexachlorobenzene (HCB), on hepatic microsomal membrane functions, were studied in female Wistar rats. Administration of HCB (100 mg/100 g b.w.) resulted in time-dependent decreases in the activity of two membrane-bound enzymes: 5'nucleotidase and Na+/K+ ATPase. HCB was found to cause a significant rise in protein tyrosine kinase (PTK) activity during the early stages of intoxication (day 2), followed by a significant decrease at 10 days, returning to control levels after 20 days of treatment. A stimulatory effect of HCB on in vitro endogenous microsomal protein phosphorylation was observed from 2 days of intoxication up to 30 days of treatment, with an important stimulation of phosphorylation at 5 days. Administration of HCB (100 mg/100 g b.w.) for 10 days caused a 50% reduction in epidermal growth factor receptor (EGF-R) ligand binding. The effects of known specific inhibitors of protein phosphatases on endogenous protein phosphorylation were studied. HCB affected the labelling of several bands, as well as the 5'nucleotidase and PTK activities, in a dose-dependent manner. In conclusion, this study indicated that the in vivo administration of HCB results in a significant alteration of membrane function.  相似文献   
92.
Mechanical stress–strain behavior of LaCoO3, La0.8Ca0.2CoO3, and La0.7Ca0.3CoO3 was studied under compression at 25° and 300°C. A hysteresis in the stress–strain relationship due to reorientation of ferroelastic domains (deformation twins) was observed, and a remanent strain is measured after unloading. The cohersive stress, defined as the maximum in effective elastic compliance during first loading, increases with substitution of Ca for La and decreases with increasing temperature. Domain reorientation was confirmed by X-ray diffraction of surfaces parallel and perpendicular to the loading direction. LaCoO3 can be regarded as a soft ferroelastic material while the 30% Ca-substituted material is a hard ferroelastic. The hysteresis of the stress–strain relationship was clearly dependent on both composition and temperature.  相似文献   
93.
In this paper, we analyse physicians’ and nurses’ practices of prescribing and administering medication through the use of paper-based, and digitalized medication plans. Our point of departure is an ethnographic study of the implications of upgrading an electronic medication module (EMM) that is part of an electronic health record (EHR), carried out at an endocrinology department. The upgrade led to a temporary breakdown of the EMM, and a return to paper-based medication plans. The breakdown made visible and noticeable the taken-for-granted capabilities of medication plans in their paper-based and digital versions, and the distribution of functionalities between medication plans and clinicians. We see the case as an opportunity to analyse infrastructuring in health care, the process by which medical practices and artefacts become parts of social and technological networks with longer reaches and more channels through which coordination among distributed actors is enabled and formed. In this case, infrastructuring means an extended scope and intensity of the coordinative capabilities of medication plans, and an increased vulnerability to, and dependency on events outside the immediate loci of interaction. We particularly note the capacity of the EMM to facilitate different kinds of ordering of information and practices, and propose the conceptualizing of such digitalized artefacts as ‘ordering devices’. Ordering devices order information, stipulate action, and coordinate interaction across and within social worlds, and achieve this through the flexible support of different kinds of ordering.  相似文献   
94.
Two studies tested the specificity of the neurocognitive profile of women with fragile X syndrome (FXS). First, women with an FXS full mutation were compared with women with a premutation and women without FXS who grew up in FXS families. Women with FXS had a significantly lower IQ than the other groups, and analyses of subtest profiles showed they had a relative weakness on Arithmetic and strength on Picture Completion. Women with FXS performed worse than the other groups on executive function, spatial ability, and visual memory. Next, women with FXS were compared with women without FXS matched on age and IQ. A similar IQ profile was found, but women with FXS were worse than controls only on executive function. The authors also examined which neurocognitive indices were related to the underlying biology of the disorder. Overall, the results indicated that executive rather than visuospatial deficits were primary in the neurocognitive profile of FXS. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
95.
Maternal lipid profiles are associated with risk for preterm birth (PTB), although the lipid component and effect size are inconsistent between studies. It is also unclear whether these associations are the result of excessive changes in lipid metabolism during pregnancy or genetic variability in genes controlling basal lipid metabolism. This study investigates the association between genetic risk scores (GRS) for four lipid components (high-density lipoprotein [HDL-C], low-density lipoprotein [LDL-C], triacylglycerols [TAG], and total cholesterol [TC]) with risk for PTB. Subjects included 954 pregnant women from California for whom second trimester serum samples were available, of which 479 gave birth preterm and 475 gave birth at term. We genotyped 96 single-nucleotide polymorphisms, which were selected from genome-wide association studies of lipid levels in adult populations. Lipid-specific GRS were constructed for HDL-C, LDL-C, TAG, and TC. The associations between GRS and PTB were analyzed using logistic regression. A higher HDL-C GRS was associated with increased risk for PTB overall and spontaneous PTB. Higher TAG and TC GRS were associated with decreased risk for PTB overall and spontaneous PTB. This study identifies counter-intuitive associations between lipid GRS and spontaneous PTB. Further replication studies are needed to confirm these findings, but they suggest that our current scientific understanding of the relationship between lipid metabolism, PTB, and genetics is incomplete.  相似文献   
96.
The levels of homovarillic acid and 3,4-dihydroxyphenylacetic acid in rat c. striatum after acute and 10 day administration of clozapine (30 and 100 mg/kg p.o.), thioridazine (100 mg/kg p.o.), haloperidol (1 mg/kg p.o.), and chlorpromazine (30 mg/kg p.o.), were estimated. With clozapine and haloperidol, the mesolimbic area was also investigated. With all these neuroleptics, the levels of both dopamine metabolites were reduced after a 10 day treatment as compared to acute administration, sometimes almost to control values. With clozapine, however, such a reduction occurred only with the higher dose of 100 mg/kg p.o., acting for a period longer than 24 h. This tolerance phenomenon was also observed with clozapine and haloperidol in the mesolimbic area. We conclude that clozapine is not qualitatively different from classical neuroleptics with respect to development of biochemical tolerance.  相似文献   
97.
The Journal of Experimental Psychology: Learning, Memory, and Cognition has long held the position as the premier international outlet for psychological studies of memory and cognition. The journal publishes work that is programmatic, rigorously designed and analyzed, and of great theoretical importance. The work published here is widely cited and includes some of the most influential studies in the field of cognitive psychology. The journal has a fairly rapid turnaround time, and the reviews are typically of high quality. As editor, I will work to ensure that all of these positive aspects remain in place, and to make changes that I believe will help the journal maintain its leadership position in the future. There are two main innovations that I will bring to the journal. The first is to broaden coverage to include more articles related to cognitive neuropsychology and cognitive neuroscience. The second is to encourage the submission of shorter empirical articles through the initiation of a Brief Reports section. I also hope to attract some of the highest quality papers in cognitive neuroscience. I encourage my colleagues whose work includes both behavioral and neuroscientific approaches to submit their best papers to JEP: LMC. I hope to be able to continue the journal's long tradition of publishing some of the best and most influential papers in experimental psychology, while opening the door a bit wider to newer perspectives. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
98.
The State-Trait Inventory for Cognitive and Somatic Anxiety (STICSA; M. J. Ree, C. MacLeod, D. French, & V. Locke, 2000) was designed to assess cognitive and somatic symptoms of anxiety as they pertain to one's mood in the moment (state) and in general (trait). This study extended the previous psychometric findings to a clinical sample and validated the STICSA against a well-published measure of anxiety, the State-Trait Anxiety Inventory (STAI; C. D. Spielberger, 1983). Patients (N=567) at an anxiety disorders clinic were administered a battery of questionnaires. The results of confirmatory factor analyses (Bentler-Bonnett nonnormed fit index, comparative fit index, and Bollen fit index>.90; root-mean-square error of approximation  相似文献   
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