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71.
In Saccharomyces cerevisiae, a complex comprising more than 20 different polypeptides assembles in a ring at the neck between the mother cell and the bud. This complex functions to coordinate cell morphology with cell division. Relatively little is known about this control system, including the physical relationships between the components of the neck ring. This study addressed the assembly interactions of three components of the ring, specifically the protein kinases Elm1p and Hsl1p and the septin Cdc12p. Specific amino acid substitutions in each of these three proteins were identified that either cause or suppress a characteristic phenotype of abnormally elongated cells and delay in the G(2)-M transition. Each protein was fused to green fluorescent protein, and its ability to localize at the neck was monitored in vivo in cells of various genotypes. Localization of Hsl1p to the neck requires Elm1p function. Elm1p localized normally in the absence of Hsl1p, although a specific point mutation in Hsl1p clearly affected Elm1p localization. The cdc12-122 mutation prevented assembly of Elm1p or Hsl1p into the neck ring. Normal assembly of Cdc12p at the neck was dependent upon Elm1p and also, to a smaller extent, on Hsl1p. Ectopic localization of Cdc12p at the bud tip was observed frequently in elm1 mutants and also, to a lesser extent, in hsl1 mutants. Thus, Elm1p is a key factor in the assembly and/or maintenance of Hsl1p, as well as at least one septin, into the bud neck ring.  相似文献   
72.
This study examined longitudinal predictors of hostility in adolescents' romantic relationships. The sample included 110 adolescents and their parents from 72 families. Observational measures of parents' marital hostility and parent-child hostility and self-reports of hostility in close friendships were collected when adolescents ranged from 14 to 16 years old. Three years later, when they were 17 to 19 years old, adolescents reported on the hostility in their romantic relationships. Results indicated that hostility in parents' marital relationships and in adolescents' friendships accounted for independent variance in hostility in adolescents' later romantic relationships. Results highlight the importance of both family relationships and friendships for predicting hostility in adolescents' romantic relationships over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
73.
The technique of Hotspot Mapping is widely used in analysing the spatial characteristics of crimes. The spatial distribution of crime is considered to be related with a variety of socio-economic and crime opportunity factors. But existing methods usually focus on the target crime density as input without utilizing these related factors. In this study, we introduce a new crime hotspot mapping tool—Hotspot Optimization Tool (HOT). HOT is an application of spatial data miming to the field of hotspot mapping. The key component of HOT is the Geospatial Discriminative Patterns (GDPatterns) concept, which can capture the differences between two classes in a spatial dataset. Experiments are done using a real world dataset from a northeastern city in the United States and the pros and cons of utilizing related factors in hotspot mapping are discussed. Comparison studies with the Hot Spot Analysis tool implemented by Esri ArcMap 10.1 validate that HOT is capable of accurately mapping crime hotspots.  相似文献   
74.
For most cancer patients, the ultimate cause of death is not the primary tumor itself, but metastasis, or the spread of cancer from the primary tumor throughout the body. The formation of tumor foci at sites distant from the primary tumor is a multistep process which includes dissemination of the cancer cells through the blood stream and hence, interactions with the endothelium lining the blood vessels walls. At least two theories have been proposed for explaining the interaction between cancer cells and endothelium. According to one theory, the tumor cells roll along the endothelium and the rolling velocity decreases until the cells become firmly attached to the vessel wall. In another theory, the circulating cancer cells must first lodge inside small vessels before they attach to the endothelium. In the latter case, the cells would only metastasize in the smaller vessels where lodging can occur. To gain further insight into the process of metastasis, the adhesion of human breast cancer cells to human umbilical vein endothelial monolayers was investigated in terms of both initial attachment followed by firm adhesion and firm adhesion following incubation in a static environment. The parallel plate flow chamber was employed to perform two different adhesion assays that would simulate these two adhesion mechanisms. Adhesion assays were carried out at a variety of physiological shear stresses found in the microvasculature and both highly metastatic and nonmetastatic cells were investigated. Results showed that initial attachment was only observed at very low shear stresses whereas firm adhesion occurred at a number of physiological shear stresses. These results suggest that the adhesion of the human breast cancer cells used in this study to endothelium most likely takes place via a lodging-firm adhesion mechanism in the capillaries and venules. However, it is important to note that other factors such as pulsatility and vessel compliance may contribute to the attachment. It was also shown that, for these specific breast cancer cells, adhesion did not correlate with metastatic potential. This suggests that while blocking the adhesion of highly metastatic cells may inhibit their ability to metastasize, adhesion properties alone do not provide an indication as to whether a cell is metastatic or nonmetastatic under the conditions studied here.  相似文献   
75.
The present study assessed drug use and the validity of self–reports of substance use among help–seeking veterans referred to a specialty clinic for the assessment of posttraumatic stress disorder (PTSD). Patients (n?=?341) were asked to provide a urine sample for use in drug screening as part of an evaluation of PTSD. Self–reports of substance use were compared with same–day supervised urine samples for 317 patients who volunteered to participate in a drug screening. Results suggested that self–reports were generally quite valid. Only 8% of the cases involved patients not reporting substance use detected by urine screens. A total of 42% of the participants were identified as using drugs of abuse (excluding alcohol) through self–report and urine drug screens. Among participants using drugs, PTSD diagnosis was significantly associated with greater marijuana and depressant use as compared with stimulant (cocaine and amphetamines) use. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
76.
77.
The integration of games into therapy provides an innovative therapeutic tool that may potentially enhance the therapeutic process. This article explores the use of games in relation to the theoretical constructs of social learning, cognitive behavioral, psychoanalytic, and gestalt theories. In addition, the author discusses types of games, therapeutic components of games, and areas that impact the use of this therapeutic tool. Finally, the article presents a method explaining how counselors can modify existing games and create their own games to incorporate within the therapeutic process for individual, family, and group therapy sessions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
78.
Helmets significantly decrease morbidity and mortality from motorcycle crashes, but many areas of the world lack universal helmet laws. To educate motorcyclists in areas without helmet laws, more knowledge of motorcyclists’ helmet beliefs is needed.A web-based survey was therefore designed to assess motorcyclists’ attitudes, norms and behaviors towards helmets in a U.S. state with a limited helmet law. Of 445 survey respondents, 68.4% of respondents reported always wearing a helmet. The not-always-helmeted riders were more likely than the always-helmeted to be male; to bave less education; and to have a history of previous motorcycle crashes and injuries. Although both groups had taken rider training classes, fewer of the not-always-helmeted had learned how to ride in a class. The strongest correlates of being not-always-helmeted (vs. always-helmeted) were attitudes that helmets were not protective and impaired sight/hearing; and the normative belief that they would only wear helmets if forced by law. Because attitudes are often more easily changed than normative beliefs, education may increase helmet use. However, less than half of riders in this state with a mandatory education program learned how to ride from a rider education course, and 44% of non-helmeted said they would only wear a helmet if forced by law. Legislation may therefore be a more efficient and effective strategy than education to increase helmet use.  相似文献   
79.
Standardized measures of cognitive ability, academic achievement, classroom learning behavior, and school social-emotional adjustment were administered for a nationally representative sample of 1,268 students aged 6–17 years. Exploratory and confirmatory latent structure analyses revealed 4 distinct and reliable student performance factors (Disciplined Behavior, Motivation, Verbal Learning, Nonverbal Learning) that were generalizable to age, sex, and ethnic subgroups within the national sample. The performance factors showed substantial and consistent relationships to independent measure of school achievement (grades, test scores) and to observations of problem behavior. Differential patterns for age, sex, and ethnic groups were discovered, including female superiority for disciplined behavior, verbal learning, and motivation, and male superiority for nonverbal learning, with unique pattern variations for some ethnic minority students. Theoretical implications are explored. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
80.
Undergraduates who completed inventories assessing for test anxiety and depression were given feedback about their level of test anxiety and asked to rate their preference for receiving an effective treatment for test anxiety. Half of the participants received effectiveness information about the potential treatments. Overall level of symptomatology was found to affect preference ratings, with higher levels of symptomatology being related to preference for a greater number of techniques. It was also found that individuals with greater levels of test anxiety were more eclectic in their preferences and tended to prefer techniques from several theoretical orientations. Effectiveness information did not influence treatment preferences, however. The need to include levels of symptomatology and more salient information about the techniques' effectiveness in future treatment preference research was discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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