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951.
This study monitored vaccine cold chain temperatures during routine DTP-HB-Hib vaccine shipments from central stores to 11 communities in 3 provinces of Bolivia. In all 11 monitored shipments, vaccines were exposed to freezing temperatures at one or more points. In each of the shipments, temperatures below 0 degrees C were recorded for 2-50% of the monitoring period. Freezing occurred at almost every level of the cold chain distribution system, especially during district and health center storage and during transport to the province and district levels. Seven of the 11 shipments were exposed to temperatures above 8 degrees C, although none were exposed to excessive heat longer than 1.3% of the total monitoring period. 相似文献
952.
Vinsky MD Murdoch GK Dixon WT Dyck MK Foxcroft GR 《Reproduction, fertility, and development》2007,19(3):430-435
Feed restriction of primiparous sows during the last week of lactation has been shown to decrease embryonic growth and female embryo survival to Day 30 of gestation. This study sought to determine whether global DNA methylation and epigenetic gene expression of the candidate genes Igf2, Igf2r, and Xist were associated with these treatment effects. Given that these epigenetic traits are expected to be important for embryo viability, changes in variance for these traits at Day 30 were predicted to be reflected in the loss of abnormal embryos at this time. Consistent with this prediction, variance in DNA methylation was reduced (P < 0.001) in Restrict male embryo, and there was a tendency for reduced variance (P < 0.06) in Restrict female embryos. Variation in DNA methylation tended to be correlated (R = 0.42, P < 0.1) with the difference in variance of embryo weights between treatments (P < 0.01), suggesting a relationship between epigenetic changes and embryonic development. Variance in Igf2r expression tended to decrease (P < 0.07) in Restrict female embryos while variance in Xist expression tended to decrease in Restrict male embryos (P < 0.08), suggesting that maternally inherited epigenetic defects may cause female embryonic loss and reduced growth before Day 30 of gestation. 相似文献
953.
Zinc is released from a subset of cerebral cortical neurons whereupon it exerts a powerful modulatory influence on excitatory and inhibitory neurotransmission. A number of studies have suggested that alterations in the regulation of zinc may contribute to the genesis of epilepsy. Here, we tested this hypothesis by examining the distribution of zinc-containing axon terminals in rats selectively bred for an innate susceptibility (FAST) or resistance (SLOW) to the development of kindling-induced seizures. Zinc was stained histochemically and levels of staining were quantitatively assessed. We found that the levels of synaptic zinc were significantly lower in the SLOW rats throughout the telencephalon. This relative reduction was most pronounced in limbic cortices where levels were less than 30% of FAST rats. These results suggest that innate differences in the homeostatic regulation of synaptic zinc, particularly in limbic cortices, may underlie differences in epileptogenicity. 相似文献
954.
Elzinga BM Ardon AM Heijnis MK De Ruiter MB Van Dyck R Veltman DJ 《Psychological medicine》2007,37(2):235-245
BACKGROUND: Memory functioning has been highlighted as a central issue in pathological dissociation. In non-pathological dissociation, evidence for enhanced working memory has been found, together with greater task-load related activity. So far, no imaging studies have investigated working memory in dissociative patients. METHOD: To assess working memory in dissociative patients functional magnetic resonance imaging was used during performance of a parametric, verbal working-memory task in patients with a dissociative disorder (n=16) and healthy controls (n=16). RESULTS: Imaging data showed that both groups activated brain regions typically involved in working memory, i.e. anterior, dorsolateral and ventrolateral prefrontal cortex (PFC), and parietal cortex. Dissociative patients showed more activation in these areas, particularly in the left anterior PFC, dorsolateral PFC and parietal cortex. In line with these findings, patients made fewer errors with increasing task load compared to controls, despite the fact that they felt more anxious and less concentrated during task performance. CONCLUSIONS: These results extend findings in non-pathological high dissociative individuals, suggesting that trait dissociation is associated with enhanced working-memory capacities. This may distinguish dissociative patients from patients with post-traumatic stress disorder, who are generally characterized by impaired working memory. 相似文献
955.
Dusseldorp E Spinhoven P Bakker A van Dyck R van Balkom AJ 《Psychotherapy and psychosomatics》2007,76(3):154-161
BACKGROUND: Beliefs about the controllability of a disorder may be relevant in the causation, maintenance and treatment of disorders. We investigated whether congruence between patients' beliefs about controllability of a panic disorder and the type of treatment provided predicted outcome. METHODS: The differential effectiveness of cognitive therapy and antidepressant treatment (paroxetine or clomipramine) was investigated in a sample of 129 panic disorder patients in a 12-week, pretest posttest placebo-controlled study. Panic frequency, agoraphobic avoidance, anxiety, depression, and disability were measured with various validated interviewer and self-report measures. Beliefs about controllability were measured with the Multidimensional Anxiety Locus of Control Scale measuring an internal, chance, therapist and medication locus of control. In order to analyze aptitude-treatment interactions a new strategy called the Regression Trunk Approach was used in addition to classical hierarchical multiple regression analysis. RESULTS: Using the Regression Trunk Approach we found that locus of control orientation (LOC) predicted the differential effectiveness of cognitive therapy. Those patients with a medium internal LOC who received cognitive therapy performed significantly better than all patients who received a placebo pill on 8 of the 10 outcome variables. We did not find a differential LOC effect for antidepressant treatment. No evidence for aptitude-treatment interactions using hierarchical multiple regression analysis was found. CONCLUSIONS: Moderately strong beliefs about self-control of panic disorder congruent with the cognitive intervention provided seem to moderate treatment effectiveness. Future studies must be more attentive to the nonlinear effects of patient characteristics on the outcome of different types of treatments. 相似文献
956.
Combination treatment for acute depression is superior only when psychotherapy is added to medication 总被引:1,自引:0,他引:1
Blom MB Jonker K Dusseldorp E Spinhoven P Hoencamp E Haffmans J van Dyck R 《Psychotherapy and psychosomatics》2007,76(5):289-297
BACKGROUND: Although several forms of effective therapy exist for outpatients suffering from major depressive disorder, many patients do not profit from treatment. Combining psychotherapy and medication may be an effective strategy. However, earlier studies have rarely found a clear advantage for the combination. Where an advantage was found, a possible placebo effect of adding 2 types of treatment could not be ruled out as cause for the superior effect of the combination. METHODS: A total of 353 patients were screened, of whom 193 were randomized over 4 conditions: nefazodone plus clinical management, interpersonal psychotherapy (IPT), the combination of the two or the combination of IPT and pill-placebo. All patients suffered from major depressive disorder and had a score of at least 14 on the 17-item Hamilton Rating Scale (HAMD). The patients were treated for 12-16 weeks. At baseline, at 6 weeks and on completion of treatment, ratings were performed by independent raters. The primary outcome measure was the HAMD, and the Montgomery-Asberg Depression Rating Scale (MADRS) the secondary outcome measure. RESULTS: Of the 193 patients included, 138 completed the trial. All treatments were effective. Using a random regression model, no differences between treatments were found on the HAMD. On the MADRS, however, the combination of medication with psychotherapy was more effective in reducing depressive symptoms compared to medication alone, but not to psychotherapy alone or IPT with pill-placebo. CONCLUSIONS: The results of this study yield support for the use of combining medication with psychotherapy instead of using medication only in the treatment of depressed outpatients. Combination treatment does not have an advantage over psychotherapy alone in the present study. 相似文献
957.
958.
R F Dyck R C Orchard D L Senger 《Clinical and investigative medicine. Médecine clinique et experimentale》1990,13(3):107-110
The purpose of this study was to investigate the plasma fibronectin response to complicated and uncomplicated acute myocardial infarction. All patients admitted to a Coronary Care Unit over a six-month period were prospectively assessed by measuring admission and daily plasma fibronectin levels using an electroimmunoassay. Of 166 patients admitted to the Unit, 66 were diagnosed as having an acute myocardial infarction. Plasma fibronectin levels were significantly lower 48 h after the onset of symptoms in 15 patients with a complicated acute myocardial infarction, compared to fibronectin levels in patients with an uncomplicated course; patients who had received intracoronary streptokinase had consistently higher plasma fibronectin levels than those seen in patients who did not receive this thrombolytic agent. This hepatocyte-derived plasma protein not only has diagnostic potential, but alterations in its levels may also provide insight into the systemic response to acute myocardial injury. 相似文献
959.
Mahmud FH Murray JA Kudva YC Zinsmeister AR Dierkhising RA Lahr BD Dyck PJ Kyle RA El-Youssef M Burgart LJ Van Dyke CT Brogan DL Melton LJ 《Mayo Clinic proceedings. Mayo Clinic》2005,80(11):1429-1434
OBJECTIVES: To estimate the prevalence of cellac disease (CD) in pediatric and adult type 1 diabetes melitus in a defined population and to describe clinical features and HLA class II genotypes predictive of CD in screened patients with type 1 diabetes. PATIENTS AND METHODS: All residents of Olmsted County, Minnesota, with type 1 diabetes mellitus on the prevalence date January 1, 2001, were identified with the use of an established medical records linkage system (Rochester Epidemiology Project) and defined clinical criteria. Consenting patients underwent serologic screening with endomyslal antibody and tissue transglutaminase antibody testing and Intestinal biopsies to confirm the diagnosis of CD. A subset of screened patients also underwent HLA class II genotyping. Quality-of-life screening (Medical Outcomes Study 36-Item Short-Form Health Survey) was completed in a subset of patients at the time of serologic screening. RESULTS: Overall, 392 Olmsted County residents with type 1 diabetes on January 1, 2001, were Identified. A total of 158 patients with type 1 diabetes were tested, representing 40% (158/392) of the enumerated diabetic population, and 11 had biopsy-proven CD for an estimated point prevalence of 7.0% (95% confidence Interval, 3.5%-12.1%). Most CD-positive diabetic patients were asymptomatic and expressed an at-risk CD haplotype with at least one of but not both HLA DQ2 or DQ8. CONCLUSIONS: Celiac disease Is not rare In North American patients with type 1 diabetes, and most CD-positive diabetic patients are asymptomatic Irrespective of age at screening. 相似文献
960.
Dehmelt H Van Dyck R Palmer F 《Proceedings of the National Academy of Sciences of the United States of America》1992,89(5):1681-1684
Compositeness of the electron may show up in a very small deviation of the measured electron g factor from one calculated for a point electron by quantum electrodynamics. The precision of our g measurements is currently limited by an interaction of the cyclotron motion with standing waves in the trap cavity containing the electron. The important element introduced here is the systematic exploration of the trap cavity modes and the electron's coupling to them by measuring the shifted electron g factor gc = gc(omega e) as a function of the cyclotron frequency omega e. By measuring gc values at five different omega e values and modeling the trap cavity by six lumped LC circuits, the L values for the four most important modes may be determined and finally the unshifted g value may be extracted. Auxiliary experiments are relied upon only for the L values of the two least critical cavity modes. By designing the trap as a high-Q microwave cavity, an electron cyclotron and anomaly resonance linewidth one or even two orders of magnitude narrower than in free space may be approached without introducing appreciable frequency shifts. 相似文献