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1.
Mannose-rich oligosaccharides have been isolated from urines of 5 patients with mannosidosis. Their compositon and structure were determined. Three of them have been previously described by Norden et al: alpha p-Manp-(1 leads to 3) beta-d-Manp-(1 leads to 4) d-GlcNAcp; alpha-p-Manp-(1 leads to 2), alpha-d-Manp-(1 leads to 3) beta-d-Manp-(1 leads to 4) d-GlcNAc and alpha-d-Manp-(1 leads to 2) alpha-d-Manp-(1 leads to 2) alpha-d-Manp-(1 leads to 3) beta-d-Manp-(1 leads to 4) d-GlcNAcp, but the four others are new entities: alpha-d-Manp-(1 leads to 3) (alpha-d-Manp-(1 leads to 2) alpha-d-Manp-(1 leads to 2) alpha-d-Manp-(1 leads to 6) beta-d-Manp-(1 leads to 4) GlcNAcp; alpha-d-Manp-(1 leads to 2) alpha-d-Manp-(1 leads to 3) (alpha-d-Manp-(1 leads to 2) alpha-d-Manp-(1 leads to 6) beta-d-Manp-(1 leads to 4) GlcNAcp; alpha-d-Manp-(1 leads to 2), alpha-d-Man-(1 leads to 3) (alpha-d-Manp-(1 leads to 6) beta-d-Manp-(1 leads to 4) GlcNAp and alpha-d-Manp-(1 leads to 2) alpha-d-Manp-(1 leads to 3) (alpha-d-Manp-(1 leads to 6) beta-d-Manp-(1 leads to 4) GlcNAcp. These structures are related to the glycans of "oligomannosidic type" present in numerous glycoproteins. All possess a N-acetylglucosamine residue in terminal reducing position and reinforce the hypothesis of Kobata et al. and Montreuil et al. that catabolism of glycans N-glucosidically linked to the protein moiety begins by the aciton of a beta-endo-N-acetylglucosaminidase.  相似文献   

2.
Burt (2009) recently published a meta-analysis of twin studies on behaviors associated with childhood psychopathologies, concluding that the finding that traits associated with attention-deficit/hyperactivity disorder (ADHD) were the only behaviors that did not show a significant influence of shared environment (C) was surprising. We agree, highlighting four methodological issues that may account for this finding: (a) the use of nonlinear transformations to normalize skewed data; (b) low power to detect C and the subsequent presentation of reduced models; (c) the negative confounding of dominant genetic (D) and C influences in twin models with data exclusively from monozygotic and dizygotic twin pairs reared together; and (d) the correction used for contrast effects (a form of rater bias), which may lead to an overestimate of additive genetic (A) or D parameters at the expense of C. We offer suggestions for future research to address these issues, and we emphasize the need for additional research to examine possible shared environmental factors related to ADHD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

3.
The authors used 3-phase context preexposure facilitation methodology to study the contribution of N-methyl-D-aspartate (NMDA) receptors in dorsal hippocampus (DH) and the basal lateral region of the amygdala (BLA) to (a) acquisition of the context memory, (b) retrieval of the context memory, (c) acquisition of context-shock association, and (d) retrieval of the context-shock association. The NMDA receptor antagonist D-2-amino-5 phosphonopentanoic acid (D-AP5) was injected into either the DH or BLA prior to (a) the context preexposure phase, (b) the immediate shock phase, or (c) the test for contextual fear. Antagonizing NMDA receptors in the DH impaired the acquisition of the context memory but did not affect its retrieval or retrieval of the fear memory. Antagonizing NMDA receptors with D-AP5 in the BLA impaired acquisition of the context-shock association but had no effect on the expression of fear. However, both DL-AP5 and L-AP5 reduced the expression of fear when they were injected into the amygdala prior to testing for contextual fear. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

4.
Juvenile court judges are often required to make distinctions as to whether certain adolescents should remain in the juvenile justice system or be transferred to adult courts. Typically, 3 broad factors weigh into juvenile court judges' decision making: (a) the level of danger the juvenile poses to the community, (b) the level of sophistication-maturity of the juvenile, and (c) the extent to which the juvenile is viewed as treatable. In an earlier study, knowledge of forensic and child psychologists was tapped to elucidate core characteristics related to the transfer process (R. T. Salekin et al, 2001). The current study augments that investigation. Judges provided (a) their perspective regarding the core criteria for dangerousness, sophistication-maturity, and amenability to treatment, and (b) data on the core characteristics of juveniles who were evaluated and subsequently judged to be appropriate for transfer to adult criminal courts. Policy implications for this increasingly critical interface between law and psychology are threefold: (a) Individualized assessments are key; (b) the adoption of a national standard for transfer to adult court is required; and (c) the development of treatment programs to improve the socialization of youth is necessary. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

5.
105 students of arts, sciences, and engineering were asked to report a dream and to take a test which measures independence of judgment and relates to creativity. 4 predictions were stated: (a) (confirmed)—the proportion of dream recallers would be greatest among art students and least among engineering students; (b) (partially confirmed)—dream imaginativeness would be greatest among art students and least among engineering students; (c) (not confirmed)—dream recallers would have higher test scores than Ss who failed to recall a dream; (d) (confirmed)—there would be a positive relation between dream imaginativeness and test scores. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

6.
Different from the grain boundary diffusion process(GBDP),which is suitable for modifying thin magnet,a green-pressing agents permeation process(GAPP) that uses low melting point alloys was applied to the Nd-Fe-B green compact with a thickness over 15 mm to reconstruct the boundary microstructure of a sintered Nd-Fe-B magnet.The coercivity increases from 12.3 kOe for the sample free of Pr_(80)Al_(20) to16.8 kOe for the sample with 2 wt% Pr_(80)Al_(20).By further increasing the Pr_(80)Al_(20) content to 3 wt%,the coercivity increases slightly,but the remanence and H_k/H_(cj) deteriorate obviously.The optimal comprehensive properties of H_(cj)=16.8 kOe,B_r=13.4 kG and H_k/H_(cj)=0.975 are obtained at 2 wt% Pr_(80)Al_(20),since matrix phase grains are separated by relatively continuous thin grain boundary layers,which weaken the magnetic coupling between adjacent grains.The coercivities of the samples from the GAPP that use2 wt% Pr_(80)Al_(20),Pr_(70)Al_(30) and Pr_(60)Tb_(20)Al_(20) alloys,respectively,can be enhanced to a large extent.However,the coercivity of the magnet reconstructed with Pr_(80)Al_(20) is lower than that of the sample with Pr_(60)Tb_(20)Al_(20) but is higher than that of the sample reconstructed with Pr_(70)Cu_(30) alloy.Moreover,the coercivity of the sample from the GAPP using 2 wt% Pr_(80)Al_(20) is much higher than that of the sample from the GBDP,which is due to a nearly uniform boundary microstructure from the surface to the interior of the thick magnet from the GAPP,thus providing new insights into the fabrication of thick and bulky permanent magnets with high coercivity.  相似文献   

7.
Eu(btc)metal organic frameworks(MOFs)were prepared by co-precipitation method via 1,2,4-benzenetricarboxylic acids(H3btc)connecting with Eu3+ions,and the morphology was controlled from compact spherical to irregular honeycomb by adjusting the pH of reaction solutions.The luminescence properties of Eu(btc)MOFs are found to be related to the surface morphology of products,and the compact spherical one performs stronger emission intensity.The sensing ability of Eu(btc)MOFs to 11 kinds of metal ions was investigated and a prominent quenching effect occurrs in Fe3+,or Ni2+solutions.Based on UV—vis absorption analysis,an“ion-fence”model presents the competition to absorb exciting light between Eu(btc)MOFs and adsorbed metal ions.Based on Stern-Volmer equation,the Eu(btc)detection is found with higher Ksv value and a lower detection limit.Meanwhile,a higher sensing efficiency is confirmed in the Eu(btc)MOFs with loose honeycomb due to aggravating porous surface offering much more sites for metal ions.  相似文献   

8.
Hexavalent chromium (Cr(VI)) contamination of soil and groundwater is a major environmental concern for some industrial sites and most of the U.S. Department of Energy sites. Cr(VI) is toxic and fairly mobile in groundwater. Bioreduction of Cr(VI) to less toxic and less mobile Cr(III) is considered to be a feasible option. Among the Cr(VI) reducing bacteria, Shewanella oneidensis MR-1 (MR-1) has been shown to be effective in metal reduction under anaerobic conditions. Data on bioreduction of Cr(VI) by MR-1 in a flow-through soil column that better approximates the subsurface condition are not available. The objective of this research project was to study the bioreduction of Cr(VI) by MR-1 in a continuous-flow quartz sand column system. MR-1 was found to be very effective in reducing Cr(VI) to Cr(III) for concentrations ranging from 0.055 mM (2.85?mg/L) to 0.006 mM (0.31?mg/L). The amount of Cr(VI) reduced prior to its breakthrough was found to be inversely proportional to its concentration in the feed due to increased inhibition of microbial activity and a residual reduction of 20–45% of Cr(VI) was observed even after its breakthrough.  相似文献   

9.
We investigated whether nitric oxide (NO) exerts an inhibition on its own synthesis in the gastric myenteric plexus in rats. Nonadrenergic, noncholinergic relaxations in response to transmural electrical stimulation (TS) were markedly antagonized by NG-nitro-L-arginine methyl ester, (10(-4) M) and abolished by tetrodotoxin (10(-6) M). Pretreatment with various NO donors (3-morpholino-sydnonymide [SIN-1 (3 x 10(-7) to 3 x 10(-6) M)], S-nitroso-N-acetylpenicillamine (10(-6) to 10(-5) M), sodium nitroprusside (10(-8) to 3 x 10(-8) M) and 8-bromoquanosine 3', 5'-cyclic monophosphate [8-bromo-cGMP (10(-6) to 3 x 10(-6) M)]) significantly inhibited TS-evoked nonadrenergic, noncholinergic relaxations in a dose-dependent manner. In contrast, vasoactive intestinal polypeptide (10(-8) M)-induced relaxations were not affected by SIN-1 or 8-bromo-cGMP. TS evoked a significant increase in 3H-citrulline formation, which was completely abolished by calcium-free medium, NG-nitro-L-arginine methyl ester, (10(-4) M) and tetrodotoxin (10(-6) M). 3H-citrulline formation evoked by TS was significantly inhibited by SIN-1 (10(-7) to 10(-5) M) and 8-bromo-cGMP (10(-7) to 10(-5) M) in a dose-dependent manner. The inhibitory effect of SIN-1 was partially prevented by 1H-[1,2, 4]oxadiazolo[3,4-a]quinoxalin-1-one (10(-5) M), a guanylate cyclase inhibitor. We conclude that NO synthesis in the gastric myenteric plexus is negatively regulated by NO and cGMP. This suggests an autoregulatory feedback mechanism of NO synthesis in the gastric myenteric plexus.  相似文献   

10.
Bilirubin kinetics were studied in an isolated, perfused rat liver system using unconjugated (14C) bilirubin (UC(14C)B) and delta-amino (4-14 C) levulinic acid (A(14 C)LA) to derive a suitable compartmental model. Plasma disappearance of UC(14C)B, plasma appearance of conjugated (14c) bilirubin (C(14C)B) and biliary excretion of C(14C)B were followed for 90-120 min following injection of UC(14C)B. Hepatic content of labeled bilirubin 12 min after the injection of UC(14C)B was determined directly in five separate perfusion experiments. UCB was found to reflux back to plasma from liver in two experiments using A(14C)LA. Bilirubin binding to red blood cells (6-8% of the perfusate level) and the components of the perfusion apparatus (4-6% of perfusate level) was estimated by performing a control experiment without the liver. A six compartment model was necessary and adequate to explain the experimental data and current knowledge of bilirubin metabolism: (1) UCB bound to red blood cells and the perfusion apparatus, (2) plasma UCB, (3) liver UCB, (4) liver CB, (5) plasma CB, and (6) bile CB. The proposed model could serve as a reference point for studies of bilirubin kinetics in whole animals for normal and abnormal states.  相似文献   

11.
Research articles published in the International Journal of Play Therapy (IJPT) were examined to investigate the use of selected statistical practices in quantitative inferential studies. The current article examined whether researchers (a) verified methodological assumptions of statistical analyses, (b) reported confidence intervals, (c) discussed the risk of experiment-wise Type I error, (d) preferred univariate analyses to multivariate analyses, (e) used univariate analyses as post hoc methods to detect multivariate effects, and (e) screened data and reported findings with graphical displays. Recommendations for improved statistical practice are provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

12.
The purpose of this project was to investigate how the goal of becoming a teacher emerges. The study used interviews to develop goal histories for 8 preservice teachers. There tended to be 4 sources of influence for their goal to become a teacher: (a) family influences, (b) teacher influences, (c) peer influences, and (d) teaching experiences. The categories developed from the interviews to describe the types of influences those sources provided were (a) suggesting that the person become a teacher, (b) encouraging the person to become a teacher, (c) modeling teaching behavior, (d) exposing the person to teaching experiences, and (e) discouraging the person from becoming a teacher. In addition, influences such as critical incidents, emotions, and social-historical factors, such as the status and pay of teachers, were prominent in the goal histories of the participants. Finally, the results of the study are discussed within the context of goals and self-directed behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

13.
This study compared 3 methods of increasing participation in substance abuse treatment for clients with traumatic brain injury. Participants (N = 195) were randomly assigned to 4 conditions: (a) motivational interview, (b) reduction of logistical barriers to attendance, (c) financial incentive, and (d) attention control. Four interviewers conducted structured, brief telephone interventions targeting the timeliness of signing an individualized service plan. Participants assigned to the barrier reduction (74%) and financial incentive (83%) groups were more likely to sign within 30 days compared with the motivational interview (45%) and attention control (45%) groups. Similar results were observed for time to signing, perfect attendance at appointments, and premature termination during the following 6 months. Extent of psychiatric symptoms was the only significant covariate. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

14.
Seven experiments show that an event onset shift (EOS) in an auditory sequence causes an involuntary phase correction response (PCR) in synchronized finger tapping. This PCR is (a) equally large in inphase and antiphase tapping; (b) reduced but still present when the EOS occurs in either of two interleaved (target- distractor) sequences; (c) unaffected by increased pitch separation between these sequences; (d) asymptotic in magnitude as EOS magnitude increases, unlike the intentional PCR to expected phase shifts; and (e) enhanced when the EOS precedes the onset of tapping, because of phase resetting. Thus, phase correction is revealed to be partially automatic and partially under voluntary control, and to be based mainly on temporal information derived from simple onset detection. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

15.
By the techniques of interferon induction in primary rabbit kidney cells "superinduced" with metabolic inhibitors, ultraviolet absorbance-temperature profiles, sensitivity to pancreatic ribonuclease A, and sucrose velocity gradient ultracentrifugation, a number of reactions between double-helical RNA and single-stranded RNA or DNA homopolymers were investigated. The polymers involved in these studies were poly(adenylic acid), poly(uridylic acid), poly(ribothymidylic acid), poly(5-bromouridylic acid), poly(deoxythymidylic acid), poly(deoxyuridylic acid), poly(3-methyluridylic acid), poly(2'-O-methyluridylic acid), and poly(2'-azido-2'-deoxyuridylic acid). Two different reaction courses, both leading to the formation of triple helices, were noted: (1) poly(Ux)-poly(A) + poly(Uy) leads to poly(Ux)-poly(A)-poly(Uy) if the Tm of poly(Ux)-poly(A) was higher than the Tm of poly(Uy)-poly(A); (2) poly(Ux)-poly(A) + poly(Uy) leads to poly(Uy)-poly(A)-poly(Ux) if the Tm of poly(Ux)-poly(A) was lower than the Tm of poly(Uy)-poly(A). In these equations, the homopolymer written to the left of poly(A) implies Watson-Crick hydrogen bonding whereas the polymer to the right of poly(A) is involved in Hoogsteen hydrogen bonding.  相似文献   

16.
Six misconceptions about evolutionary approaches to human behavior are exposed. Evidence is adduced to support the assertions that evolutionary approaches do not (a) adopt a reductionistic "gene-centered" level of analysis, (b) assume that natural selection is the only process that creates and designs ontogenetic processes and phenotypic outcomes, (c) assume that genes are the only agents responsible for the transgenerational inheritance of phenotypic traits and characteristics, (d) assume that genes are self-contained and impervious to extragenetic influences, (e) posit a strong form of genetic determinism, or (f) pay lip service to the role of the environment. Building straw men and knocking them down is an inherently destructive enterprise; integrating different approaches is a more constructive way of contributing to the growth of knowledge. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

17.
A multisite, randomized trial within the National Drug Abuse Treatment Clinical Trials Network (CTN) was conducted to test 3 interventions to enhance treatment initiation following detoxification: (a) a single session, therapeutic alliance intervention (TA) added to usual treatment; (b) a 2-session, counseling and education, HIV/HCV risk reduction intervention (C&E), added to usual treatment; and (c) treatment as usual (TAU) only. Injection drug users (n = 632) enrolled in residential detoxification at 8 community treatment programs were randomized to 1 of the 3 study conditions. TA participants reported entering outpatient treatment sooner and in greater numbers than TAU participants. Reported treatment entry for C&E fell between TA and TAU with no significant differences between C&E and the other conditions. There were no differences among the interventions in retention, as measured by weeks of outpatient treatment for all participants who reported treatment entry. Alliance building interventions appear to be effective in facilitating transfer from detoxification to outpatient treatment, but additional treatment engagement interventions may be necessary to improve retention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
In this paper, the authors report on the development and initial psychometric evaluation of the Lesbian, Gay, and Bisexual Working Alliance Self-Efficacy Scales (LGB-WASES) with data collected from two studies and 534 counseling trainees. Exploratory factor analysis results yielded a 32-item scale with a three-factor model (a) Emotional Bond, (b) Establishing Tasks, and (c) Setting Goals. LGB-WASES scores were internally consistent and remained stable over a 3-week period. Construct validity evidence suggests the LGB-WASES scores were (a) positively related to general perceptions of counseling self-efficacy and multicultural counseling competency, (b) negatively related to attitudes toward lesbians and gay men, and (d) unrelated to social desirability. Recommendations for future research are also discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

19.
Different issues raised in the commentaries are elaborated in this reply. The focus was on the following five topics: (a) the nature of storage deficits in the patient groups and the different meanings that can be attached to it, (b) the possible explanations for the disordered responses of the patients, (c) suggestions for the use of other techniques to study semantic deficits, (d) the Warrington and Shallice criteria to distinguish between access and storage problems, and (e) some technical (statistical) issues raised in the commentaries. The reply concludes by highlighting the key findings reported in the target article that seem to be accepted by the large majority of the commentators. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

20.
INTRODUCTION: High atrial defibrillation energy requirements (ADER) in patients with chronic atrial fibrillation (AF) may limit the acceptance of transvenous atrial defibrillation. We evaluated an optimized defibrillation electrode configuration that could help to reduce the ADER in patients with AF. METHODS AND RESULTS: We tested ten different configurations in nine dogs with AF (3.33+/-2.92 days) induced by rapid atrial pacing. The configurations were: right atrial (RA) appendage as anode and coronary sinus (CS) as cathode; RA and innominate vein (I) as anode to CS (cathode); RA-CS (anode) to I (cathode); I-CS (anode) to RA (cathode); RA and left lateral subcutaneous patch (P) as anode to CS (cathode); RA-CS (anode) to P (cathode); P-CS (anode) to RA (cathode); superior vena cava (SVC) and CS (anode) to RA (cathode); RA-CS (anode) to SVC (cathode); and RA-SVC (anode) to CS (cathode). ADER was defined as the voltage needed to defibrillate the atria in 10% to 90% of 20 consecutive shocks. Three lead systems had ADER lower than the RA (anode) to CS (cathode) configuration, which required a mean of 143+/-58 volts. These three were: RA-SVC (anode) to CS (cathode) 103+/-29 V; I-CS (anode) to RA (cathode) 129+/-39 V; and P-CS (anode) to RA (cathode) 130+/-38 V. The remaining configurations had ADER higher than the RA (anode) to CS (cathode) configuration. CONCLUSION: Adding an additional shocking electrode may reduce ADER when compared with the RA (anode) to CS (cathode) configuration. This concept could be incorporated into future implantable atrial defibrillators or used for refractory patients undergoing temporary transvenous cardioversion.  相似文献   

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