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This study explores the gender differences in the experience of dating violence by using a multivariate approach and sampling a racially/ethnically and socioeconomically diverse population. The social learning theory and feminist theory were the theoretical frameworks used to guide this study. The final sample included 939 students (385 boys and 554 girls) in public high schools in the Los Angeles area. The data revealed that gender differences are not significant to the total dating violence experienced. Males reported physical abuse (e.g., being slapped and hit with a fist or object) more often than females, while females reported significantly more sexual abuse than males. Both males and females reported that males were more frequently the initiators of dating violence. With regard to perceived causes of dating violence, victims in both sexes indicated that the most frequent reason for their partners? violence was jealousy. For many males, females? use of physical aggression in dating relationships is not taken seriously, possibly because difference in physical strength. The females? responses to violence indicated greater emotional and psychological injury. Finally, this study identified 4 predictor variables that differ significantly by gender; namely, race, self-esteem, justification of violence, and infliction of dating violence.  相似文献   
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p53 and MDM2 expression in odontogenic cysts and tumours   总被引:1,自引:0,他引:1  
OBJECTIVE: The aim of this report was to assess p53 and MDM2 expression in odontogenic cysts and tumours, as they are known to play important roles in cell proliferation and tumorigenesis. MATERIALS AND METHODS: The expression of p53 and MDM2 proteins was determined immunohistochemically in 51 formalin-fixed, paraffin embedded specimens of odontogenic cysts and tumours.RESULTS: No positivity to p53 was found in the cases studied. MDM2 expression in ameloblastoma was higher than in radicular cysts, but lower than that observed in odontogenic keratocysts. No difference was observed between MDM2 expression in radicular cyst and adenomatoid odontogenic tumour. The clear-cell odontogenic ameloblastoma presented strong immunoreaction to this antigen.CONCLUSIONS: The results suggest that MDM2 overexpression may be involved in the pathogenesis of some odontogenic lesions.  相似文献   
65.
Gluckman PD, Sizonenko SV, Bassett NS. The transition from fetus to neonate - an endocrine perspective. Acta Pædiatr 1999; Suppl 428: 7–11. Stockholm. ISSN 0803–5326
The transition from fetus to neonate involves three phases: late gestation, parturition and the processes needed to establish independent homoeostatic regulation after separation from the placenta. These phases are regulated by a series of fetal and placental endocrine events. Glucocorticoids have an important role in the preparation for birth, including involvement in lung and cardiac development, and the maturation of enzymes in a variety of pathways. Fetal Cortisol production is, in turn, also under hormonal control. Parturition is a complex process, which is still poorly understood in humans. The final steps are largely dependent on the effect of prostaglandin F on the myometrium associated with increased oxytocin activity. The transition to birth is accompanied by changes in respiration, circulation, glucose homoeostasis, and the onset of independent oral feeding and thermoregulation. Several examples of endocrine components of the transition from fetal to neonatal life are reviewed here: the role of prostanoids, the onset of thermogenesis, and changes in the thyroid hormone and growth hormone axes. The effects of hormone levels on prematurity and growth retardation are also discussed. □ Birth transition, fetus, gestation, hormonal control, neonate, parturition  相似文献   
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AIM: To evaluate existing evidence for the association between different type of brassiere exposures and the risk of breast cancer. METHODS: Ovid Medline, CINAHL, Cochrane Data Base of Systematic Reviews, Pubmed, Scopus, Proquest, Sciencedirect, Wiley Online Library, WanFang Data, Hong Kong Index to Chinese Periodicals, China Journal Net, Chinese Medical Current Contents, Chinese Biomedical Literature Database, China Academic Journals Full-Text database, Taiwan Electronic Periodical Services and HyRead; reference lists of published studies; original research studies published in English or Chinese examining the association between type and duration of brassiere-wearing and breast cancer risk. Data were abstracted by a first reviewer and verified by a second. Study quality was rated according to predefined criteria. “Fair” or “good” quality studies were included. Results were summarised by meta-analysis whenever adequate material was available. RESULTS: Twelve case-control studies were included in the review. Meta-analysis showed brassiere wearing during sleep was associated with a two times of increased odds. CONCLUSION: The present review demonstrates insufficient evidence to establish a positive association between the duration and type of brassiere wearing and breast cancer. Further research is essential; specifically, a large-scale epidemiological study of a better design is needed to examine the association between various forms of brassiere exposure in detail and breast cancer risk, with adequate control of confounding variables.  相似文献   
68.
Objectives:  To determine the extent to which clinical and radiographic features of bisphosphonate-associated osteonecrosis of the jaw (BONJ) are correlated.
Design:  Retrospective case review.
Methods:  The records of 39 patients diagnosed with BONJ and examined by panoramic radiography were retrospectively evaluated. The arches were divided into sextants ( n  = 234) and evaluated for the following signs: sclerosis, surface irregularity, sockets, fragmentation and lysis.
Main outcome measures:  The McNemar, Kruskall–Wallis and equivalency tests were performed to analyze the association between clinical and radiographic signs and BONJ severity.
Results:  Sixty-two out of 234 sextants were abnormal by clinical criteria and 61 out of 234 sextants demonstrated at least one radiographic abnormality. There was agreement between clinical and radiographic detection in 41 sextants. The data showed equivalency between BONJ diagnosis and both sclerosis and surface irregularity. The correlation between number of clinical sites and any radiographic finding was significant in the maxilla ( P  < 0.001) but not in the mandible ( P  = 0.178). The total number of radiographic signs per patient increased with BONJ stage.
Conclusion:  Focal panoramic radiographic findings of sclerosis and surface irregularity correlate with clinical sites of BONJ. This may be a useful and reliable tool to detect early changes of BONJ or to confirm a clinical diagnosis.  相似文献   
69.

BACKGROUND AND PURPOSE

BAF312 is a next-generation sphingosine 1-phosphate (S1P) receptor modulator, selective for S1P1 and S1P5 receptors. S1P1 receptors are essential for lymphocyte egress from lymph nodes and a drug target in immune-mediated diseases. Here, we have characterized the immunomodulatory potential of BAF312 and the S1P receptor-mediated effects on heart rate using preclinical and human data.

EXPERIMENTAL APPROACH

BAF312 was tested in a rat experimental autoimmune encephalomyelitis (EAE) model. Electrophysiological recordings of G-protein-coupled inwardly rectifying potassium (GIRK) channels were carried out in human atrial myocytes. A Phase I multiple-dose trial studied the pharmacokinetics, pharmacodynamics and safety of BAF312 in 48 healthy subjects.

KEY RESULTS

BAF312 effectively suppressed EAE in rats by internalizing S1P1 receptors, rendering them insensitive to the egress signal from lymph nodes. In healthy volunteers, BAF312 caused preferential decreases in CD4+ T cells, Tnaïve, Tcentral memory and B cells within 4–6 h. Cell counts returned to normal ranges within a week after stopping treatment, in line with the elimination half-life of BAF312. Despite sparing S1P3 receptors (associated with bradycardia in mice), BAF312 induced rapid, transient (day 1 only) bradycardia in humans. BAF312-mediated activation of GIRK channels in human atrial myocytes can fully explain the bradycardia.

CONCLUSION AND IMPLICATIONS

This study illustrates species-specific differences in S1P receptor specificity for first-dose cardiac effects. Based on its profound but rapidly reversible inhibition of lymphocyte trafficking, BAF312 may have potential as a treatment for immune-mediated diseases.  相似文献   
70.
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