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101.
PURPOSE: To quantify the risks of intrauterine antiepileptic drug (AED) exposure in monotherapy and polytherapy. METHODS: Data from five prospective European studies totaling 1,379 children were pooled and reanalyzed. Data were available for 1,221 children exposed to AED during pregnancy and for 158 children of unexposed control pregnancies. RESULTS: Overall, when comparing a subgroup of 192 children exposed to AED with 158 children of matched nonepileptic controls, there was an increased risk of major congenital malformations (MCA) in children exposed to AED during gestation [relative risk (RR) 2.3; 95% confidence interval (CI): 1.2-4.7]. A significant increase in risk was found for children exposed to valproate (VPA) (RR 4.9; 95% CI: 1.6-15.0) or carbamazepine (CBZ) (RR 4.9; 95% CI: 1.3-18.0) in monotherapy. When comparing different AED regimens during all 1,221 pregnancies, risks of MCA were significantly increased for the combination of phenobarbital (PB) and ethosuximide (RR 9.8; 95% CI: 1.4-67.3) and the combination of phenytoin, PB, CBZ, and VPA (RR 11.0; 95% CI: 2.1-57.6). Offspring of mothers using > 1,000 mg VPA/day were at a significantly increased risk of MCA, especially neural tube defects, compared to offspring exposed < or =600 mg VPA/day (RR 6.8; 95% CI: 1.4-32.7). No difference in risk of MCA was found between the offspring exposed to 601-1,000 mg/day and < or =600 mg/day. CONCLUSIONS: This reanalysis shows that VPA is consistently associated with an increased risk of MCA in babies born to mothers with epilepsy. Significant associations were also observed with CBZ. Larger prospective population-based studies are needed to evaluate the risks of many other less frequently prescribed treatment regimens, including newly marketed AEDs.  相似文献   
102.
Psychoanalysis today is largely a psychology of consciousness: Post- and neo-Freudians form a marginalized community within North America in comparison to contemporary relational and intersubjective theorists, who emphasize the phenomenology of lived conscious experience, dyadic attachments, affective attunement, social construction, and mutual recognition over the role of insight and interpretation. Despite the rich historical terrain of theoretical variation and advance, many contemporary approaches have displaced the primacy of the unconscious. Notwithstanding the theoretical hairsplitting that historically occurs across the psychoanalytic domain, one is beginning to see with increasing force and clarity what S. Mitchell and L. Aron (1999) referred to as the emergence of a new tradition, namely, relational psychoanalysis. Having its edifice in early object relations theory, the British middle school and American interpersonal traditions, and self psychology, relationality is billed as "a distinctly new tradition" (Mitchell & Aron, 1999, p. x). What is being labeled as the American middle group of psychoanalysis (C. Spezzano, 1997), relational and intersubjective theory have taken center stage. It may be argued, however, that contemporary relational and intersubjective perspectives have failed to be properly critiqued from within their own school of discourse. The scope of this article is largely preoccupied with tracing (a) the philosophical underpinnings of contemporary relational theory, (b) its theoretical relation to traditional psychoanalytic thought, (c) clinical implications for therapeutic practice, and (d) its intersection with points of consilience that emerge from these traditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
103.
In a previous paper, we studied elementary models for polymerization, depolymerization, and fragmentation of actin filaments (Edelstein-Keshet and Ermentrout, 1988, Bull. Math. Biol. 60, 449-475). When these processes act together, more complicated dynamics occur. We concentrate on a particular case study, using the actin-fragmenting protein gelsolin. A set of biological parameter values (drawn from the experimental literature) is used in computer simulations of the kinetics of gelsolin-mediated actin filament fragmentation.  相似文献   
104.
OBJECTIVE: To compare the tolerability of angiotensin-converting enzyme (ACE) inhibitors with that of angiotensin II (AII)-receptor blockers and the incidence of cough and angioedema associated with their use through review of published data. DATA SOURCES: References were identified through a MEDLINE search of articles published between January 1975 and April 1997. Bibliographies of pertinent references were also reviewed. RESULTS: Results of placebo-controlled and comparative trials of the AII blockers demonstrate that they are at least as effective as ACE inhibitors for hypertension, but exhibit an incidence of cough and absent or rare angioedema like that of placebo. CONCLUSIONS: In the 10 comparative trials described, all reported a lower incidence of cough with AII blockers than with ACE inhibitors. Angioedema was not reported in the comparative trials described.  相似文献   
105.
BACKGROUND/PURPOSE: Fetuses with congenital diaphragmatic hernia (CDH) who have a "poor prognosis" with postnatal treatment now can be identified on the basis of liver herniation, early diagnosis (before 25 weeks' gestation) and a low lung-to-head ratio (LHR). Because complete in utero repair proved unsuccessful for this group, the strategy of temporary tracheal occlusion was developed to gradually enlarge the hypoplastic fetal lung. The purpose of this study is to compare the outcome of patients in the poor-prognosis group treated by one of three methods: (1) standard postnatal care, (2) fetal tracheal occlusion via open hysterotomy, and (3) the recently developed video-fetoscopic (Fetendo) technique of tracheal occlusion without hysterotomy. METHODS: In the past 3 years, 34 of 86 fetuses with an isolated left CDH met criteria for the poor-prognosis group. Thirteen families chose postnatal treatment at an extracorporeal membrane oxygenation (ECMO) center, 13 underwent open fetal tracheal occlusion, and eight underwent fetoscopic tracheal occlusion. RESULTS: The survival rate was 38% in the group treated by standard postnatal therapy, 15% in the open tracheal occlusion group, and 75% in the Fetendo group. There were less postoperative pulmonary complications noted in mothers who underwent the Fetendo procedure versus the open tracheal occlusion. All but one Fetendo clip patient had a striking physiological response demonstrated by sonographic enlargement of the small left lung that was documented postnatally by plain radiographs and its subjective appearance during repair of the CDH. In contrast, only 5 of the 13 open tracheal occlusion patients demonstrated lung growth. CONCLUSION: Fetuses with a left CDH who have liver herniation and a low LHR are at high risk of neonatal demise and appear to benefit from temporary tracheal occlusion when performed fetoscopically, but not when performed by open fetal surgery.  相似文献   
106.
The purpose of the study was the evaluation of low-dose spiral CT in the detection and assessment of contours of pulmonary nodules. In a prospective investigation 71 consecutive chest CT examinations were acquired both at 30 and 200 mA. Films were interpreted independently by two radiologists. According to the size, nodules were divided into four categories: 10 mm; nodule shape was registered. With both protocols, 240 nodules were detected. The correlation coefficient for both methods was 0.89. Discrepancies were found most frequently in nodules near to pulmonary vessels. Nodule size estimation did not differ more than one size category. Eight spiculated nodules were identified by both techniques. Low-dose spiral CT of the chest has a high sensitivity in the detection of pulmonary nodules. If clinical circumstances require dose minimization, low-dose spiral CT may be advocated as an alternative screening method to conventional dose spiral CT.  相似文献   
107.
In the Kruger National Park, male lions, Panthera leo, acquire most of their food by hunting rather than scavenging. This study, the most intensive to date of male lion ecology, showed that in savanna woodlands, with high buffalo, Syncerus caffer, densities, male lions were frequent and successful hunters. The main prey species of all male group types, but particularly nonterritorial males, was buffalo. By contrast, females preyed more frequently on the most abundant medium-sized ungulates, such as wildebeest, Connochaetes taurinus, and zebra, Equus burchelli. Thus intraspecific prey selection separation was based primarily on intersexual and, to a lesser extent, social differences. Furthermore, both nonterritorial males and pride females located their favoured prey, buffalo and medium-sized ungulates, respectively, more often than other prey. We investigated the influence of several ecological variables on the socioecology of male lions, particularly as we had determined that territorial males spent little time with their pride females and tended to hunt by themselves in their respective male coalitions. Further analysis showed that in a range of ecosystems in southern and eastern Africa the proportion of time territorial males spent with, and thus scavenged from, their pride females was strongly influenced by vegetation structure, and therefore probably by the assemblage of available ungulates. In open systems, territorial males were, therefore, likely to be encountered with pride females, whereas in more wooded areas they were likely to be encountered away from their pride females. We suggest that this is because vegetation structure influences food/prey availability and hunting success and influences territory maintenance and/or cub defence. (c) 1998 The Association for the Study of Animal Behaviour.  相似文献   
108.
We have analyzed both conformational and functional changes caused by two large cis-acting deletions (delta 159 and delta 549) located within the read-through domain, a 850 nucleotide hairpin, in coliphage Q beta genomic RNA. Studies in vivo show that co-translational regulation of the viral coat and replicase genes has been uncoupled in viral genomes carrying deletion delta 159. Translational regulation is restored in deletion delta 549, a naturally evolved pseudorevertant. Structural analysis by computer modeling shows that structural features within the read-through domain of delta 159 RNA are less well determined than they are in the read-through domain of wild-type RNA, whereas predicted structure in the read-through domain of evolved pseudorevertant delta 549 is unusually well determined. Structural analysis by electron microscopy of the genomic RNAs shows that several long range helices at the base of the read-through domain, that suppress translational initiation of the viral replicase gene in the wild-type genome, have been destabilized in delta 159 RNA. In addition, the structure of local hairpins within the read-through region is more variable in delta 159 RNA than in wild-type RNA. Stable RNA secondary structure is restored in the read-through domain of delta 549 RNA. Our analyses suggest that structure throughout the read-through domain affects the regulation of viral replicase expression by altering the likelihood that long-range interactions at the base of the domain will form. We discuss possible kinetic and equilibrium models that can explain this effect, and argue that observed changes in structural plasticity within the read-through domain of the mutant genomes are key in understanding the process. During the course of these studies, we became aware of the importance of the information contained in the energy dot plot produced by the RNA secondary structure prediction program mfold. As a result, we have improved the graphical representation of this information through the use of color annotation in the predicted optimal folding. The method is presented here for the first time.  相似文献   
109.
Abnormal optical properties of liquid-crystalline dispersions (phases) formed as a result of phase exclusion of double-stranded DNA and RNA from water-salt poly(ethylene glycol) solutions and X-ray parameters of these phases are compared. It is shown that the cholesteric packing of nucleic acid molecules is realized at the certain osmotic pressure of a solvent only. A comparison of the optical properties of liquid-crystalline phases (dispersions) to their X-ray parameters allows one to put forward a suggestion on various hydratation (fluctuation) regimes of the nucleic acid behaviour under the condensed phases formation and factors, influencing the mode of packing of these molecules in phases formed. It is shown as well, that immobilization of DNA cholesteric liquid-crystalline particles in the content of polymeric matrix is accompanied by the stabilization of these particles and, hence, their specific abnormal optical activity as well as by formation of particles having a structure, which corresponds to the "optically isotropic ordered liquid" without abnormal optical activity. Data on stabilization of the cholesteric structure of liquid-crystalline DNA dispersions by creation of polymeric chelate bridges between the neighbouring DNA molecules, fixed in the structure of liquid-crystalline dispersions, are shown.  相似文献   
110.
DNA photolyases repair pyrimidine dimers via a reaction in which light energy drives electron donation from a catalytic chromophore, FADH-, to the dimer. The crystal structure of Escherichia coli photolyase suggested that the pyrimidine dimer is flipped out of the DNA helix and into a cavity that leads from the surface of the enzyme to FADH-. We have tested this model using the Saccharomyces cerevisiae Phr1 photolyase which is >50% identical to E. coli photolyase over the region comprising the DNA binding domain. By using the bacterial photolyase as a starting point, we modeled the region encompassing amino acids 383-530 of the yeast enzyme. The model retained the cavity leading to FADH- as well as the band of positive electrostatic potential which defines the DNA binding surface. We found that alanine substitution mutations at sites within the cavity reduced both substrate binding and discrimination, providing direct support for the dinucleotide flip model. The roles of three residues predicted to interact with DNA flanking the dimer were also tested. Arg452 was found to be particularly critical to substrate binding, discrimination, and photolysis, suggesting a role in establishing or maintaining the dimer in the flipped state. A structural model for photolyase-dimer interaction is presented.  相似文献   
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