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91.
The birth of cells with neurogenic potential in the adult brain is assessed commonly by detection of exogenous S phase markers, such as bromodeoxyuridine (BrdU). Analysis of other phases of the cell cycle, however, can provide insight into how external factors, such as opiates, influence the cycling of newly born cells. To this end, we examined the expression of two endogenous cell cycle markers in relation to BrdU: proliferating cell nuclear antigen (PCNA) and phosphorylated histone H3 (pHisH3). Two hours after one intraperitoneal BrdU injection, BrdU-, PCNA-, and pHisH3-immunoreactive (IR) cells exhibited similar distribution in the adult mouse subgranular zone (SGZ). Quantitative analysis within the SGZ revealed a relative abundance of cells labeled for PCNA > BrdU > pHisH3. Similar to our reports in rat SGZ, chronic morphine treatment decreased BrdU- and PCNA-IR cells in mouse SGZ by 28 and 38%, respectively. We also show that pHisH3-IR cells are influenced by chronic morphine to a greater extent (58% decrease) than are BrdU- or PCNA-IR cells. Cell cycle phase analysis of SGZ BrdU-IR cells using triple labeling for BrdU, PCNA, and pHisH3 revealed premature mitosis in chronic morphine-treated mice. These results suggest that morphine-treated mice have a shorter Gap2/mitosis (G(2)/M) phase when compared to sham-treated mice. These findings demonstrate the power of using a combination of exogenous and endogenous cell cycle markers and nuclear morphology to track proliferating cells through different phases of the cell cycle and to reveal the regulation of cell cycle phase by chronic morphine.  相似文献   
92.
BackgroundRecent evidence supports the efficacy of programs that promote improvements in the health practices of workers 50 years and older who are at higher risk for chronic diseases than younger workers are. Internet-based programs that promote healthy practices have also shown promise and, therefore, should be especially appropriate for workers aged 50 years and older.ObjectiveThe purpose of the research was to evaluate the effectiveness of HealthyPast50, a fully automated Web-based health promotion program based on social cognitive theory and aimed specifically at workers 50 years and older.MethodsThe randomized controlled trial was conducted across multiple US offices of a large global information technology company. The sample included 278 employees aged 50 to 68 who were recruited online and randomly assigned to the Web-based HealthyPast50 program or to a wait-list control condition. Self-report measures of diet, physical activity, stress, and tobacco use were collected online before and 3 months after the program group was given access to the program. Use data included number of log-ins and number of pages accessed. The primary analysis was multiple linear regression, following intent-to-treat principles with multiple imputation using the Markov chain Monte Carlo (MCMC) approach for nonmonotone missing data. Potential moderators from demographic characteristics and program dosage effects were assessed using multiple linear regression models. Additional analyses were conducted on complete (nonimputed) cases, excluding program participants who used the program for less than 30 minutes.ResultsRetention rates were good for both groups: 80.4% (111/138) for the program group and 94.3% (132/140) for the control group. Program group participants spent a mean of 102.26 minutes in the program (SD 148.32), logged in a mean of 4.33 times (SD 4.28), and viewed a mean of 11.04 pages (SD 20.08). In the analysis of the imputed dataset, the program group performed significantly better than the control group on diet behavioral change self-efficacy (estimated adjusted difference [Δ]=0.16, P=.048), planning healthy eating (Δ=0.17, P=.03), and mild exercise (Δ=1.03, P=.01). Moderator and dosage analyses of the dataset found no significant program effects. Analyses of the nonimputed dataset comparing program users with controls found additional significant program effects on eating practices (Δ=0.09, P=.03), exercise self-efficacy (Δ=0.12, P=.03), exercise planning (Δ=0.18, P=.03), and aging beliefs (Δ=0.17, P=.01). Moderator analysis of this dataset also found significant moderator effects of gender on multiple measures of exercise.ConclusionsA Web-based health promotion program showed promise for making a significant contribution to the short-term dietary and exercise practices of older working adults. Gender effects suggest that the program effects on exercise are due mainly to improvements among women.  相似文献   
93.

Objectives

Means of objectively assessing white spot enamel lesions (WSEL) are critical for determining their potential activity and monitoring the success of preventive treatments. The aim of this study was to determine whether surface pH measurements of WSEL changed during a preventive course of care designed to remineralize the lesions.

Methods

Eight healthy subjects (1 male and 7 females) with at least one WSEL were recruited (19–64 years). Each subject was placed on a preventive treatment program including the daily application of a CPP-ACP paste (MI paste, GC Corp., Japan) with custom fitted trays for more than 6 months. The surface pH values of sound enamel and WSEL were monitored for up to 2 years using a micro-pH sensor. The visual appearance of the WSEL was monitored via digital photography, and images were analyzed qualitatively on a 5-point scale to assess the success of the remineralization preventive program. The relationship between the qualitative assessment of WSEL appearance and the WSEL pH was investigated using a Spearman's rho non-parametric correlation.

Results

The surface pH of the WSEL was different to that of the sound enamel surrounding it in all patients at all times. All lesions showed visual improvement as the treatment period progressed. The pH of the WSEL increased towards that of sound enamel over the course of treatment significantly correlating with the visual improvement of the lesion (rho = 0.63, p < 0.0001).

Conclusions

The clinical assessment of WSEL surface pH changes with time may have utility as an additional objective measure for the assessment of WSEL activity.  相似文献   
94.

Introduction  

Proposed criteria for resection of pancreatic cystic lesions have included symptoms, size (>3 cm), and suspicious features by endoscopic ultrasound (EUS). The objective of this study was to evaluate risk factors for malignancy in a large series of patients undergoing resection of suspected pancreatic cystic neoplasms.  相似文献   
95.
96.
Using field‐based observations and standardized measures of the home environment and child development, the authors followed 59 rural Jamaican women and their offspring from birth to age 5. The findings suggest that conjugal multiplicity, a female reproductive pattern characterized by multiple unions, maternal unmarried status, and absent father, does not necessarily result in poorer developmental outcomes for preschool‐aged children. Rather, it is a strategic adaptation to the conditions of poverty that may, in fact, provide developmental advantages for poor children in rural Jamaica. Households in which there are six or more maternal siblings, however, appear to compromise child development regardless of multiple unions, conjugal status, or father's presence.  相似文献   
97.
Objective: To assess gender differences in the relationship between eating and weight loss attitudes (EWAs), and 30-day tobacco and alcohol use among adolescents, while controlling for potential confounds (age, country of birth, psychological distress, pubertal development, peer alcohol and tobacco use, and sexual activity). Methods: School students aged between 11 and 17 years (N = 10,273) from high schools in the State of Victoria (Australia) completed surveys in class under conditions of anonymity and confidentiality. Results: The interaction between EWAs and gender was significant for tobacco use but not for alcohol use, indicating that the effect of EWAs on tobacco use, but not alcohol use, vary by gender. Conclusions: Tobacco use was related to EWAs in adolescent females but not males, and this is consistent with the possibility that females use tobacco in an instrumental fashion to control weight. Implications and Contribution: Female adolescents high in eating and weight loss attitudes were more likely to engage in tobacco use. In contrast, eating and weight loss attitudes were not related to male tobacco use. These results point to the potential importance of developing gender-specific approaches towards addressing problematic behaviors in adolescent populations.  相似文献   
98.
Background Pharmacists?? involvement in outpatient dialysis centres in Australia is currently limited, despite the positive contribution of pharmacists to renal patients?? medication management and health outcomes outlined in the literature. An expanded role for pharmacists in this setting may be required as a consequence of the increasing burden of renal disease in the population. Objective To explore renal-specialised hospital pharmacists?? intentions to implement pharmacy services in outpatient dialysis centres. Setting Australian renal-specialised hospital pharmacists. Method Semi-structured interviews were conducted with a purposeful sample of renal pharmacists recruited through the Society of Hospital Pharmacists of Australia Renal Special Interest Group. The interview guide was developed based on the theory of planned behaviour. To identify behavioural intention, the three components of the theory??attitudes, subjective norm, and perceived behavioural control??were explored. The interviews were recorded, transcribed verbatim, and thematically content analysed following a qualitative approach. Main Outcome Measures Pharmacists?? views on their potential involvement and perceived ease or difficulty in implementing pharmacy services in outpatient dialysis centres. Results Thirteen renal pharmacists were interviewed until data saturation achievement. The following services for this setting were suggested: medication reconciliation, medication review, patient education, promotion of compliance, involvement in protocol development with subsequent anaemia/phosphate management. Pharmacists demonstrated positive attitudes towards the implementation of the services. Outcomes expected included benefits to patients, the renal team, and the pharmacy profession, as well as economic savings due to dose optimisation and improvement of patients?? adherence. Subjective norm was favourable meaning that nephrologists, nurses and patients were expected to be receptive towards future pharmacy services. Barriers pointed out for the implementation comprised: funding, hospital administrators?? approval, time and staff shortage, academic training, relationship with physicians, and attitudes of pharmacists, renal team, and patients. Facilitators mentioned by respondents included: having an interview room with access to information sources, consent from the team, access to patients?? profiles, and a full-time pharmacist with a clearly defined role. Conclusion Pharmacists showed positive attitudes, favourable subjective norm and strong perceived behavioural control, which originated a clear behavioural intention to develop pharmacy services in outpatient dialysis centres. The potential barriers and enablers outlined should be taken into account, as well as the holistic approach for the successful implementation of cognitive pharmacy services.  相似文献   
99.
As countries implement Article 11 of the World Health Organization (WHO) Framework Convention on Tobacco Control, graphic warning labels that use images of people and their body parts to illustrate the consequences of smoking are being added to cigarette packs. According to exemplification theory, these case examples—exemplars—can shape perceptions about risk and may resonate differently among demographic subpopulations. Drawing on data from eight focus groups (N = 63) with smokers and nonsmokers from vulnerable populations, this qualitative study explores whether people considered exemplars in their reactions to and evaluations of U.S. graphic health warning labels initially proposed by the Food and Drug Administration. Participants made reference to prior and concurrent mass media messages and exemplars during the focus groups and used demographic cues in making sense of the images on the warning labels. Participants were particularly sensitive to age of the exemplars and how it might affect label effectiveness and beliefs about smoking. Race and socioeconomic status also were salient for some participants. We recommend that exemplars and exemplification be considered when selecting and evaluating graphic health warnings for tobacco labels and associated media campaigns.  相似文献   
100.
The current study examined the relations between children’s perceptions of character social realism, identification with characters, trust of characters as knowledgeable informants, and learning from media characters. Thirty-six 3½- to 6-year-old children watched a short clip of an animated educational television program about a preschool-aged boy who enjoys learning about science. Participants provided ratings of the character’s social realism, their identification with the character, and their trust in the character as a knowledgeable informant. Participants were asked to solve problems based on information in the video clip. Findings revealed character trust was the strongest indicator of learning from the character. Results are discussed in the context of the different factors that influence learning from curriculum-based media for young children.  相似文献   
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