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Anneloes Dirks Lucianne Groenink Koen G C Westphal Jocelien D A Olivier P Monika Verdouw Jan van der Gugten Mark A Geyer Berend Olivier 《Neuropsychopharmacology》2003,28(10):1790-1798
Chronically elevated levels of corticotropin-releasing factor (CRF) in transgenic mice overexpressing CRF in the brain (CRF-OE) appear to be associated with alterations commonly associated with major depressive disorder, as well as with sensorimotor gating deficits commonly associated with schizophrenia. In the present study, we tested the hypothesis that antipsychotics may be effective in normalizing prepulse inhibition (PPI) of acoustic startle in CRF-OE mice, which display impaired sensorimotor gating compared to wild-type (WT) mice. The typical antipsychotic haloperidol and atypical antipsychotic risperidone improved PPI in the CRF-OE mice, but were ineffective in WT mice. The atypical antipsychotic clozapine did not influence PPI in CRF-OE mice, but reduced gating in WT mice. This effect of clozapine in the CRF-OE mice may thus be regarded as a relative improvement, consistent with the observed effect of haloperidol and risperidone. As expected, the anxiolytic, nonantipsychotic chlordiazepoxide was devoid of any effect. All four compounds dose-dependently reduced the acoustic startle response irrespective of genotype. These results indicate that antipsychotic drugs are effective in improving startle gating deficits in the CRF-OE mice. Hence, the CRF-OE mouse model may represent an animal model for certain aspects of psychotic depression, and could be a valuable tool for research addressing the impact of chronically elevated levels of CRF on information processing. 相似文献
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F A Althaus 《Family planning perspectives》1991,23(4):173-177
Using recent data from the U.S., the argument is reiterated that sexually transmitted diseases (STDs) have serious consequences on female morbidity, mortality, pregnancy outcome and that the cost of screening and treatment can afford significant savings. Since the rosy view of the 1950s that STDs had been eliminated with penicillin, new viral, parasitic and bacterial forms have emerged, and antibiotic-resistant classical STDs have increased yearly. 13 million new cases were reported in 1989, excluding non-reportable diseases and asymptomatic infections, such as over half of chlamydia cases. Mortality is possible from STDs, most notably from AIDS, now among the top 5 causes of death of women aged 15-44. Other fatal outcomes are cervical cancer related to human papilloma virus, accelerated by HIV, pelvic inflammatory diseases (PID) its consequences, ectopic pregnancy. Symptomatic PID affects 1 million women, resulting in 210,000 hospitalizations per year. Ectopic pregnancy accounts for 12% of maternal mortality. STDs are involved in neonatal infections with HIV, syphilis, gonorrhea, chlamydia, cytomegalovirus, and herpes. Chorioamnionitis, a finding in many miscarriages, is caused by many of the same organisms. Several studies have projected sizeable potential savings, even within the current year, by providing STD screening and treatment in family planning clinics and prenatal care, in terms of prevention of hospitalization of women, and intensive care for low birth weight, premature and infected newborns. 相似文献
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Claus D. Eisenbach Andreas Gldel Monika Terskan-Reinold Ulrich S. Schubert 《Macromolecular chemistry and physics.》1995,196(4):1077-1091
The synthesis and properties of segmented ABA triblock and (AB)n multiblock copolymer systems with 6,6′-disubstituted 2,2′-bipyridine (bpy) building blocks B and poly(oxytetramethylene) soft segments A are described. The access to the disubstituted bipyridines in large scale quantities was achieved by modification of conventional synthetic routes. In the presence of copper(I) ions these polymers formed mononuclear [Cu(I)(bpy)2] complexes in solution through self-assembly. The complexed copolymers were microphase separated systems in bulk with nano to mesoscopic superstructures consisting of copper-bpy complex aggregates in a polyether matrix. The thermal, mechanical and elastomer properties of the block copolymers varied with composition. 相似文献
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Influence of failed arterial reconstruction on the outcome of major limb amputation. 总被引:2,自引:0,他引:2
BACKGROUND. Unsuccessful vascular repair may further preexisting limb ischemia and thus increase the risk of revascularization procedures. METHODS. The results of 94 primary major amputations (group A) have been analyzed and compared with 112 secondary ablations (group B) carried out after failed revascularization efforts. All patients suffered from chronic critical ischemia (grades III and IV) of the lower extremities. In group A the severity of ischemic symptoms was more pronounced (trophic changes in 80% vs 66% in group B), and a preponderance for older age, diabetes mellitus, and incidence of cardiac failure and cerebrovascular insufficiency was evident. RESULTS. In patients undergoing secondary amputation the final transection level was adversely affected by preceding unsuccessful reconstructive attempts. In spite of the better risk profile, 30% of patients in group B were subjected to above-knee amputation compared with 13% of patients in group A. The aggravated limb ischemia caused by graft failure is reflected by the decrease of the mean ankle systolic pressure index from 0.27 to 0.13 (before and after failed revascularization attempts). Although more amputations at the below-knee level were performed initially in group A, primary wound healing was obtained among these subjects in 68% of patients (compared with only 39% for patients in group B). CONCLUSIONS. In a substantial number of cases preexisting limb ischemia may be promoted by failed attempts at vascular reconstruction, thus leading to severe wound healing complications and a higher level of amputation. 相似文献