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91.
OBJECTIVE: This study explored psychosocial and "environmental" correlates of childhood anxiety disorders. The study examined relationships among parental psychiatric symptomatology, perceived family environment, temperament, and self-competence in children with a DSM-III-R anxiety disorder. METHOD: A community sample of third through sixth graders was screened initially for symptoms of test anxiety. Those with high and low scores were administered the Anxiety Disorders Interview Schedule for Children. Three groups (childhood anxiety disorder, test-anxious only, and normal controls) were identified and compared on the psychosocial variables. RESULTS: Children with an anxiety disorder had greater impairment on the indices of perceived self-competence and temperamental flexibility than controls, with the test-anxious children showing intermediate, yet significant, levels of disturbance. There was a trend for children with an anxiety disorder to describe their families as less promoting of independence than the other groups. Finally, measures of parental psychiatric symptomatology revealed more obsessive-compulsive symptoms for the fathers of both the anxiety disorder and test-anxious children compared with controls. CONCLUSIONS: Results are consistent with previous findings suggesting the familial transmission of anxiety disorders and recent speculations regarding a relationship between behavioral inhibition, environmental control, and anxiety. Further research may isolate psychosocial and family environmental factors as instrumental treatment targets in the management of childhood anxiety disorders.  相似文献   
92.
In this paper, a new approach for the numerical solution of coupled electromechanical problems is presented. The structure of the considered problem consists of the low‐frequency integral formulation of the Maxwell equations coupled with Newton–Euler rigid‐body dynamic equations. Two different integration schemes based on the predictor–corrector approach are presented and discussed. In the first method, the electrical equation is integrated with an implicit single‐step time marching algorithm, while the mechanical dynamics is studied by a predictor–corrector scheme. The predictor uses the forward Euler method, while the corrector is based on the trapezoidal rule. The second method is based on the use of two interleaved predictor–corrector schemes: one for the electrical equations and the other for the mechanical ones. Both the presented methods have been validated by comparison with experimental data (when available) and with results obtained by other numerical formulations; in problems characterized by low speeds, both schemes produce accurate results, with similar computation times. When high speeds are involved, the first scheme needs shorter time steps (i.e., longer computation times) in order to achieve the same accuracy of the second one. A brief discussion on extending the algorithm for simulating deformable bodies is also presented. An example of application to a two‐degree‐of‐freedom levitating device based on permanent magnets is finally reported. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
93.
A cell line that produces an autoantibody specific for DNA quadruplex structures has been isolated and cloned from a hybridoma library derived from 3-month-old nonimmunized autoimmune, immunodeficient "viable motheaten" mice. This antibody has been tested extensively in vitro and found to bind specifically to DNA quadruplex structures formed by two biologically relevant sequence motifs. Scatchard and nonlinear regression analyses using both one- and two-site models were used to derive association constants for the antibody-DNA binding reactions. In both cases, quadruplexes had higher association constants than triplex and duplex molecules. The anti-quadruplex antibody binds to the quadruplex formed by the promoter-region-derived oligonucleotide d(CGCG4GCG) (Ka = 3.3 x 10(6) M-1), and has enhanced affinity for telomere-derived quadruplexes formed by the oligonucleotides d(TG4) and d(T2G4T2G4T2G4T2G4) (Ka = 5.38 x 10(6) and 1.66 x 10(7) M-1, respectively). The antibody binds both types of quadruplexes but has preferential affinity for the parallel four-stranded structure. In vitro radioimmunofilter binding experiments demonstrated that purified anti-DNA quadruplex antibodies from anti-quadruplex antibody-producing tissue culture supernatants have at least 10-fold higher affinity for quadruplexes than for triplex and duplex DNA structures of similar base composition and length. The antibody binds intramolecular DNA triplexes formed by d(G4T3G4T3C4) and d(C4T3G4T3G4), and the duplex d(CGCGCGCGCG)2 with an affinities of 6. 76 x 10(5), 5.59 x 10(5), and 8.26 x 10(5) M-1, respectively. Competition experiments showed that melted quadruplexes are not effective competitors for antibody binding when compared to native structures, confirming that the quadruplex is bound structure-specifically. To our knowledge, this is the first immunological reagent known to specifically recognize quadruplex structures. Subsequent sequence analysis demonstrates homologies between the antibody complementarity determining regions and sequences from Myb family telomere binding proteins, which are hypothesized to control cell aging via telomeric DNA interactions. The presence of this antibody in the autoimmune repertoire suggests a possible linkage between autoimmunity, telomeric DNA binding proteins, and aging.  相似文献   
94.
Analysis of the S-phase fractions (SPF) measured by in vitro thymidine labeling, morphological appearances, and estrogen receptor (ER) assays of primary invasive breast carcinomas demonstrated several interrelationships. Lobular, mucinous, tubular, and adenocystic carcinomas consistently had low SPF and were usually positive for ER. The same was true for the carcinomas of no special histologic type [the not otherwise specified (NOS) group of E. R. Fisher including "infiltrating ductal" and undifferentiated carcinomas] with minimal anaplasia. Medullary, atypical medullary, and morphologically unclassifiable carcinomas with marked nuclear anaplasia nearly always had high SPF and were usually negative for ER. High SPF was associated with advanced stages of carcinoma initially or with early recurrence following mastectomy.  相似文献   
95.
During a cardiovascular survey, aimed at detecting cases of latent coronary heart disease (CHD), glucose elimination was studied after i.v. loading in 1970 presumably healthy men aged 40-59 years. The aim was to throw light on the importance of deranged glucose tolerance for the development of CHD. Of the 1970 individuals, 1798 were defined as "normals", 33 had chronic, non-anginal chest pain, 34 had slight albeit typical angina pectoris. The remaining 105 had various symptoms/signs strongly suggestive of CHD, and underwent diagnostic coronary angiography (69 angiopositive, 36 angionegative). Plasma insulin was determined in relation to the test in 249 of the subjects. The following conclusions were reached: 1) Mean k-values were similar in all subgroups (p less than 0.10). 2) Low and borderline k-values were significantly more frequent in angiographed individuals compared with the group of normals (p less than 0.025). However, an almost identical frequency was seen in angiopositive and angionegative cases. 3) K-values did not change with age between 40 and 59 years. 4) K-values were unrelated to the severity of angiographic findings in individuals with proven CHD. 5) Significantly lower k-values were found in individuals with a positive diabetic heredity, and 6) in individuals with a high insulin response. 7) The i.v. glucose loading did not influence an exercise ECG recorded in relation to a near-maximal bicycle exercise test.  相似文献   
96.
The aim of this study is to show histological and immunofluorescence analysis of renal parenchyma of agoutis affected by gentamicin‐induced renal disease after the infusion of bone marrow mononuclear cells (BMMC) stained with Hoechst®. Nine agouti's males were divided into three groups: Test group (TG): renal disease by gentamicin induced (n = 3), cell therapy group (CTG): renal disease by gentamicin induced and BMMC infusion (n = 3), and control group (CG): nonrenal disease and BMMC infusion (n = 3). TG and CTG were submitted to the protocol of renal disease induction using weekly application of gentamicin sulfate for 4 months. CG and CTG received a 1 × 108 BMMC stained with Hoechst and were euthanized for kidney examination 21 days after BMMC injection and samples were collected for histology and immunofluorescence analysis. Histological analysis demonstrated typical interstitial lesions in kidney similarly to human disease, as tubular necrosis, glomerular destruction, atrophy tubular, fibrotic areas, and collagen deposition. We conclude that histological analysis suggest a positive application of agouti's as a model for a gentamicin inducing of kidney disease, beyond the immunofluorescence analysis suggest a significant migration of BMMC to sites of renal injury in CTG. Microsc. Res. Tech., 2012. © 2011 Wiley Periodicals, Inc.  相似文献   
97.
Myocardial biopsies from two patients who had developed "stone heart" (myocardial rigor mortis; ischemic contracture of the left ventricle) were studied by electron microscopy. The ultrastructure of tissue in stone heart, though ischemic in nature, differed from that of classic myocardial infarction in some respects. Apart from depletion of glycogen and distension of the sarcoplasmic reticulum and T-tubules, myofibrillar degeneration was much more widespread. Mitochondrial degeneration with active lysosomal autodigestion, disruption of the microcirculation, and lymphedema were prominent changes also observed. In the light of known clinical and experimental observations, our findings suggest that stone heart is an accelerated form of ischemic injury occurring in vulnerable (hypertrophied) hearts and is probably related to ischemia-triggered release of endogenous catecholamines.  相似文献   
98.
The virtual classroom provides an efficient and scalable tool for conducting attention testing. The University of Southern California integrated media systems center and digital media works have partnered to develop virtual reality technology applications for the study, assessment, and rehabilitation of cognitive and functional processes. This work primarily focuses on the development of systems that address the special needs of clinical populations with central nervous system dysfunctions such as brain injury, learning disabilities, or neurological disorders.  相似文献   
99.
The need for a multidisciplinary approach for characterizing water bodies in terms of morphological, chemical and ecological quality has hastened the growth of hydromorphology as a cross‐disciplinary topic at the interface of hydrology, geomorphology and ecology. Many authors have analysed how hydroecology may affect freshwater biodiversity, although little is known about how this biodiversity might be affected by river morphological quality. We examined how well the presence of the semi‐aquatic Eurasian otter can be predicted by the rivers' morphological quality and its adjustments over the last decades. We tested the morphological quality index (MQI) methodology in 38 reaches of five rivers in southern Italy, 23 of which were positive to otter presence. In each reach, we examined 28 indicators contributing to the MQI and its 11 sub‐indices. The results showed a significant relationship between the probability of the presence of otters, MQI, and some sub‐indices. The best performing sub‐indices were related to channel adjustments and the continuity of river processes. A more detailed analysis of channel adjustments showed a detrimental effect of channel incision (>3 m) and a positive effect of narrowing, particularly where it occurred simultaneously with the development of forest in the new floodplain. The continuity of river processes has driven the migration of river banks and the development of ponds and secondary channels, likely increasing the availability of dens and resting sites and the hunting capabilities of otters. Our results stressed the importance of fluvial dynamics and sustainable adaptive river management for the habitat quality of semi‐aquatic species. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
100.
This pilot study assessed the utility and acceptability of the VirtuSphere, a cutting edge navigation platform designed to enhance presence in virtual environments. The VirtuSphere includes a 12-ft hollow sphere within which the user stands, and it rolls within a wheeled platform, in any direction, according to the user's steps. The pilot was a within-subject crossover design comparing the VirtuSphere to standard game controller navigation. The comparison was based on locomotion in Virtual Iraq, a virtual world resembling Iraqi war zones. Participants were 10 active duty soldiers not suffering from posttraumatic stress disorder. Results indicated that there were negligible differences in sense of presence, simulator sickness, and satisfaction across the two navigation systems. Although the VirtuSphere may provide entertainment value, these results do not provide initial support for the use of the VirtuSphere to improve constructs thought to be important to behavioral health applications of virtual reality. Potential improvements to the design of the VirtuSphere are discussed.  相似文献   
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