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71.
BACKGROUND: Few published reports in the dental literature have focused on adult attention-deficit/hyperactivity disorder (ADHD) and its dental implications. TYPES OF STUDIES REVIEWED: The authors conducted a MEDLINE search for the period 2000 through 2005 using the terms "adult" and "attention-deficit" to define ADHD's pathology, medical treatment and dental implications. RESULTS: ADHD is a developmental condition that affects slightly more than 4 percent of the adult U.S. population. Its symptoms include inattention, hyperactivity and impulsivity that can cause personal, social, occupational and leisure-time dysfunction. Medications used to treat the disorder include stimulants, selective noradrenergic uptake inhibitors and tricyclic antidepressants. CLINICAL IMPLICATIONS: The oral health of people with ADHD may be compromised by inattention and impulsivity that impair home care regimens and can lead to cigarette addiction, which may cause oral cancer and damage the periodontium, and excessive ingestion of caffeinated sugar-laden soft drinks that promote dental caries. To safely care for this patient population, dentists must be familiar with the stimulant and nonstimulant medications used to treat adult ADHD, because these drugs can cause adverse orofacial and systemic reactions and interact adversely with dental therapeutic agents.  相似文献   
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The electrophysiological response to hyperkalaemia was reinvestigated in the whole dog for several reasons including: the paucity of comparative electrophysiological and electrocardiographical studies in which atrial and ventricular tissues were simultaneously investigated; the contrast between the clarity of findings in previous in vitro studies as compared with the rather conflicting results in earlier in vivo investigations; and the difficulty in validating the extrapolation from in vitro results and theory to the in vivo situation because of deficiences in the literature. Biphasic alterations in atrial and ventricular conduction times as well as excitability in response to progressively increasing hyperkalaemia were documented. The alterations in conduction times were reflected quite accurately by relevant electrocardiographical changes. Experiments in the whole animal were designed to test predictions based on membrane theory: the results offering strong support for the validity of extrapolating from the in vitro to the in vivo situation. The results of this study should help clarify and render interpretable many of the seemingly conflicting results in the literature.  相似文献   
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Lew  VL; Raftos  JE; Sorette  M; Bookchin  RM; Mohandas  N 《Blood》1995,86(1):334-341
Using flow cytometry and osmotic lysis measurements, we document here the means and coefficients of variation of the following red cell (RBC) properties: hemoglobin (Hb) content, volume, Hb concentration, and relative lytic tonicity distributions in populations of normal human RBCs, before and after density fractionation. The distributions showed a pattern characterized by much larger coefficients of variation of the Hb content and volume distributions than of the Hb concentration and relative lytic tonicity distributions. From analysis of the factors that determine those RBC properties, the patterns were interpreted as reflecting previously unrecognized statistical proportionalities between cell osmolyte content, Hb content, and membrane area. The possible origin of these statistical links was analyzed by considering alternative models with and without the participation of regulatory processes during cell maturation. A model was shown to be feasible in which mature RBC variability with proportional volume, area, and Hb content arises solely from cell size variability at the last erythroid cell division.  相似文献   
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This report describes the effect of pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF) on platelet production and platelet function in humans. Subjects with advanced solid tumors received PEG-rHuMGDF daily for up to 10 days. There was no increase in circulating platelet count at doses of 0.03 or 0.1 microgram/kg/d by day 12 of study. At doses of 0.3 and 1.0 microgram/kg/d there was a threefold median increase (maximum 10-fold) in platelet count by day 16. The platelets produced in vivo in response to PEG-rHuMGDF showed unchanged aggregation and adenosine triphosphate (ATP)-release responses in in vitro assays. Tests included aggregation and release of ATP in response to adenosine diphosphate (ADP) (10, 5, 2.5, and 1.25 mumol/L), collagen (2 micrograms/mL), thrombin-receptor agonist peptide (TRAP, 10 mumol/L) and ristocetin (1.5 mg/mL). Administration of aspirin to an individual with platelet count of 1,771 x 10(3)/L resulted in the typical aspirin-induced ablation of the normal aggregation and ATP-release response to stimulation with arachidonic acid (0.5 mg/mL), collagen, and ADP (2.5 and 1.25 mumol/L). There was no change in the expression of the platelet-surface activation marker CD62P (P-selectin) nor induction of the fibrinogen binding site on glycoprotein IIb/IIIa as reported by the monoclonal antibody, D3GP3. An elevation of reticulated platelets was evident after 3 days of treatment with PEG-rHuMGDF and preceded the increase in circulating platelet count by 5 to 8 days; this reflected the production of new platelets in response to PEG-rHuMGDF. At later time points, the mean platelet volume (MPV) decreased in a manner inversely proportional to the platelet count. Levels of plasma glycocalicin, a measure of platelet turnover, rose 3 days after the initial increase in the peripheral platelet count. The level of plasma glycocalicin was proportional to the total platelet mass, suggesting that platelets generated in response to PEG-rHuMGDF were not more actively destroyed. Thus, the administration of PEG-rHuMGDF, to humans, increased the circulating platelet count and resulted in fully functional platelets, which showed no detectable increase in reactivity nor alteration in activation status.  相似文献   
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Background Involving service users and carers in decisions about their health care is a key feature of health‐care practice. Professional health and social care students need to develop skills and attributes to best enable this to happen. Aims The aims were to explore service user and carer perceptions of behaviours, attributes and context required to enable shared decision making; to compare these perceptions to those of students and academic staff with a view to utilizing the findings to inform the development of student assessment tools. Methods A mixed methods approach was used including action learning groups (ALG) and an iterative process alongside a modified Delphi survey. Participants The ALGs were from an existing service user and carer network. The survey was sent to sixty students, sixty academics and 30 service users from 16 different professional disciplines, spanning four Universities in England. Results The collaborative enquiry process and survey identified general agreement that being open and honest, listening, showing respect, giving time and being up to date were important. The qualitative findings identified that individual interpretation was a key factor. An unexpected result was an insight into possible insecurities of students. Conclusions The findings indicate that distilling rich qualitative information into a format for student assessment tools could be problematic as the individual context could be lost, it is therefore proposed that the information could be better used as a learning rather than assessment tool. Several of those involved identified how they valued the process and found it beneficial.  相似文献   
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Background

Social connection is a fundamental human need. Its absence can lead to loneliness and social isolation, adversely impacting health and well-being. Given their regular contact and trusted relationships with older people, practitioners delivering community-based primary care are well-positioned to address this issue. However, their contribution to addressing loneliness and social isolation is unclear.

Aim

This integrative review explores the contribution of the primary care workforce to interventions aimed at reducing loneliness and social isolation in community-dwelling older people.

Method

Using an integrative review method, Scopus, Web of Science, CINAHL and PubMed were searched for original research published between 2000 and 2022. Fourteen papers reporting 13 primary studies were appraised for methodological quality and included in the review. Data were extracted into a summary table and analysed using thematic analysis.

Results

Included studies came from over six countries. Internationally, primary care services have diverse structures, funding and workforces influencing their response to loneliness and social isolation. All but one intervention was multi-component, with ten studies including a group-based activity and three providing primarily individual-level activities. Only six studies reported reductions in loneliness following the intervention. Three themes were identified: characteristics of interventions; implementation context, barriers and facilitators; and differing contributions of primary care practitioners in addressing loneliness and social isolation of older people.

Conclusion

There is increasing demand and scope for primary care practitioners to assist lonely and socially isolated older people. It is important to understand how to equip and incentivise these practitioners to routinely identify, assess and respond to lonely and socially isolated older people despite varying implementation contexts. There is a need for further research that explores how the primary care team can be better utilised to deliver effective interventions that reduce the health impacts of loneliness and social isolation.  相似文献   
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