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81.
82.
BackgroundHeadache disorders are highly prevalent worldwide, but not well investigated in adolescents. Few studies have included representative nationwide samples. This study aimed to present the prevalence and burden of recurrent headache in Australian adolescents.MethodsThe prevalence of recurrent headache, headache characteristics (severity and frequency) and burden on health-related quality of life in Australian children aged 10–17 years were presented, using nationally representative data from the Longitudinal Study of Australian children (LSAC). The LSAC, commencing in 2004, collects data every 2 years from a sample of Australian children of two different age cohorts: B ‘baby’ cohort, aged 0–1 years and K ‘kindergarten’ cohort, aged 4–5 years at the commencement of the study. Face-to-face interviews and self-complete questionnaires have been conducted with the study child and parents of the study child (carer-reported data) at each data collection wave, with seven waves of data available at the time of the current study. Wave 7 of the LSAC was conducted in 2016, with B cohort children aged 12–13 years and K cohort children aged 16–17 years. For the current study, data were accessed for four out of seven waves of available data (Wave 4–7) and presented cross-sectionally for the two cohorts of Australian children, for the included age groups (10–11 years, 12–13 years, 14–15 years and 16–17 years). All available carer-reported questionnaire data pertaining to headache prevalence, severity and frequency, general health and health-related quality of life, for the two cohorts, were included in the study, and presented for male and female adolescents. Carer-reported general health status of the study child and health-related quality of life scores, using the parent proxy-report of the Paediatric Quality of Life Inventory™ 4.0, were compared for male and female adolescents with recurrent headache and compared with a healthy group. Finally, health-related quality of life scores were compared based on headache frequency and severity.ResultsThe LSAC study initially recruited 10,090 Australian children (B cohort n = 5107, K cohort n = 4983), and 64.1% of the initial sample responded at wave 7. Attrition rates across the included waves ranged from 26.3% to 33.8% (wave 6 and 7) for the B cohort, and 16.3% to 38.0% (wave 4–7) for the K cohort. Recurrent headache was more common in females, increasing from 6.6% in 10–11 years old females to 13.2% in 16–17 years old females. The prevalence of headache in males ranged from 4.3% to 6.4% across the age groups. Health-related quality of life scores were lower for all functional domains in adolescents with recurrent headache, for both sexes. Headache frequency, but not severity, was significantly associated with lower health-related quality of life scores, in both males and females.ConclusionsRecurrent headache was common among Australian adolescents and increased in prevalence for females, across the age groups. Frequent recurrent headache is burdensome for both male and female adolescents. This study provides information regarding the prevalence and burden of recurrent headache in the adolescent population based on findings from the Longitudinal Study of Australian Children.  相似文献   
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The internal iliac artery (IIA) arises from the common iliac artery at the level of the sacroiliac joint. It descends as trunk, divides into anterior and posterior divisions. From the anterior division it gives superior vesical, obturator, middle rectal, inferior vesical, inferior gluteal, and internal pudendal arteries. In females, inferior vesical artery is replaced by vaginal artery and gives an additional branch, uterine artery. The branches from the posterior division are ilio lumbar, lateral sacral, and superior gluteal arteries. An accidental hemorrhage and neurovascular injuries are common due to erroneous interpretation of variant arteries during surgical procedures. Hence the present study has been undertaken with reference to highlight its clinical and surgical significances. The study included 50 human bisected pelvises irrespective of their side and sex. Formalin-fixed specimens were selected and the branching patterns of IIA were studied. The level of origin, length, and the branching pattern of the IIA were examined and tabulated. The present study highlighted the variation seen in the origin, division branches of the IIA. The detailed knowledge of morphology is essential for successful ligation of the IIA during acute hemorrhage. This will guide the interventional radiologist in intra-arterial procedures during arterial embolization for hemorrhage, control of pelvic fractures, during selective catheterization of the intra-arterial chemotherapy, and embolization of the pelvic tumors.  相似文献   
85.
Dysfunction of pacemaker activity in the sinoatrial node (SAN) underlies “sick sinus” syndrome (SSS), a common clinical condition characterized by abnormally low heart rate (bradycardia). If untreated, SSS carries potentially life-threatening symptoms, such as syncope and end-stage organ hypoperfusion. The only currently available therapy for SSS consists of electronic pacemaker implantation. Mice lacking L-type Cav1.3 Ca2+ channels (Cav1.3−/−) recapitulate several symptoms of SSS in humans, including bradycardia and atrioventricular (AV) dysfunction (heart block). Here, we tested whether genetic ablation or pharmacological inhibition of the muscarinic-gated K+ channel (IKACh) could rescue SSS and heart block in Cav1.3−/− mice. We found that genetic inactivation of IKACh abolished SSS symptoms in Cav1.3−/− mice without reducing the relative degree of heart rate regulation. Rescuing of SAN and AV dysfunction could be obtained also by pharmacological inhibition of IKACh either in Cav1.3−/− mice or following selective inhibition of Cav1.3-mediated L-type Ca2+ (ICa,L) current in vivo. Ablation of IKACh prevented dysfunction of SAN pacemaker activity by allowing net inward current to flow during the diastolic depolarization phase under cholinergic activation. Our data suggest that patients affected by SSS and heart block may benefit from IKACh suppression achieved by gene therapy or selective pharmacological inhibition.Pacemaker activity of the sinoatrial node (SAN) controls heart rate under physiological conditions. Abnormal generation of SAN automaticity underlies “sick sinus” syndrome (SSS), a pathological condition manifested when heart rate is not sufficient to meet the physiological requirements of the organism (1). Typical hallmarks of SSS include SAN bradycardia, chronotropic incompetence, SAN arrest, and/or exit block (13). SSS carries incapacitating symptoms, such as fatigue and syncope (13). A significant percentage of patients with SSS present also with tachycardia-bradycardia syndrome (3). SSS can also be associated with atrioventricular (AV) conduction block (heart block) (13). Although aging is a known intrinsic cause of SSS (4), this disease appears also in the absence of any associated cardiac pathology and displays a genetic legacy (1, 2). Heart disease or drug intake can induce acquired SSS (2). Symptomatic SSS requires the implantation of an electronic pacemaker. SSS accounts for about half of all pacemaker implantations in the United States (5, 6). The incidence of SSS has been forecasted to increase during the next 50 y, particularly in the elder population (7). Furthermore, it has been estimated that at least half of SSS patients will need to be electronically paced (7). Although pacemakers are continuously ameliorated, they remain costly and require lifelong follow-up. Moreover, the implantation of an electronic pacemaker remains difficult in pediatric patients (8). Development of alternative and complementary pharmacological or molecular therapies for SSS management could improve quality of life and limit the need for implantation of electronic pacemakers.Recently, the genetic bases of some inherited forms of SSS have been elucidated (recently reviewed in 1, 9) with the discovery of mutations in genes encoding for ion channels involved in cardiac automaticity (4, 9, 10). Notably, loss of function of L-type Cav1.3 Ca2+ channels is central in some inherited forms of SSS. For instance, loss of function in Cav1.3-mediated L-type Ca2+ (ICa,L) current causes the sinoatrial node dysfunction and deafness syndrome (SANDD) (10). Affected individuals with SANDD present with profound deafness, bradycardia, and dysfunction of AV conduction (10). Mutation in ankyrin-B causes SSS by reduced membrane targeting of Cav1.3 channels (11). The relevance of Cav1.3 channels to SSS is demonstrated also by work on the pathophysiology of congenital heart block, where down-regulation of Cav1.3 channels by maternal Abs causes heart block in infants (12). Additionally, recent data show that chronic iron overload induces acquired SSS via a reduction in Cav1.3-mediated ICa,L (13).In mice and humans, Cav1.3 channels are expressed in the SAN, atria, and the AV node but are absent in adult ventricular tissue (14, 15). Cav1.3-mediated ICa,L plays a major role in the generation of the diastolic depolarization in SAN and AV myocytes, thereby constituting important determinants of heart rate and AV conduction velocity (14, 16). The heart rate of mice lacking Cav1.3 channels (Cav1.3−/− mice) fairly recapitulates the hallmarks of SSS and associated symptoms, including bradycardia and tachycardia-bradycardia syndrome (17, 18). In addition, severe AV dysfunction is recorded in Cav1.3−/− mice to variable degrees. Typically, these mice show first- and second-degree AV block (16, 17, 19). Complete AV block with dissociated atrial and ventricular rhythms can also be observed in these animals. The phenotype of Cav1.3−/− mice thus constitutes a unique model for developing new therapeutic strategies against SSS (10).The muscarinic-gated K+ channel (IKACh) is involved in the negative chronotropic effect of the parasympathetic nervous system on heart rate (20, 21). Two subunits of the G-protein activated inwardly rectifying K+ channels (GIRK1 and GIRK4) of the GIRK/Kir3 subfamily assemble as heterotetramers to form cardiac IKACh channels (22). Indeed, both Girk1−/− and Girk4−/− mice lack cardiac IKACh (20, 21, 23). We recently showed that silencing of the hyperpolarization-activated current “funny” (If) channel in mice induces a complex arrhythmic profile that can be rescued by concurrent genetic ablation of Girk4 (24). In this study, we tested the effects of genetic ablation and pharmacological inhibition of IKACh on the Cav1.3−/− mouse model of SSS. We found that Girk4 ablation or pharmacological inhibition of IKACh rescues SSS and AV dysfunction in Cav1.3−/−. Thus, our study shows that IKACh targeting may be pursued as a therapeutic strategy for treatment of SSS and heart block.  相似文献   
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87.
Lung transplant survival is limited by obliterative bronchiolitis (OB), but the mechanisms of OB development are unknown. Previous studies in a mouse model of orthotopic lung transplantation suggested a requirement for IL‐17. We have used this orthotopic mouse model to investigate the source of IL‐17A and the requirement for T cells producing IL‐17A. The major sources of IL‐17A were CD4+ T cells and γδ T cells. Depletion of CD4+ T cells led to a significantly decreased frequency and number of IL‐17A+ lymphocytes and was sufficient to prevent acute rejection and OB. However, mice with STAT3‐deficient T cells, which are unable to differentiate into Th17 cells, rejected lung allografts and developed OB similar to control mice. The frequency of IL‐17A+ cells was not decreased in mice with STAT3‐deficient T cells due mainly to the presence of IL‐17A+ γδ T cells. Deficiency of γδ T cells also did not affect the development of airway fibrosis. Our data suggest that CD4+ T cells are required for OB development and expansion of IL‐17A responses in the lung, while Th17 and γδ T cells are not absolutely required and may compensate for each other.  相似文献   
88.
Clinical leadership has been identified as crucial to positive patient/client outcomes, across all clinical settings. In the new millennium, transformational leadership has been the dominant leadership style and in more recent times, congruent leadership theory has emerged to explain clinical leadership in nursing. This article discusses these two leadership models and identifies some of the shortcomings of them as models for clinical leadership in nursing. As a way of overcoming some of these limitations, aesthetic leadership is proposed as a style of leadership that is not antithetical to either model and reflects nursing's recognition of the validity of art and aesthetics to nursing generally. Aesthetic leadership is also proposed as a way to identify an expert clinical leader from a less experienced clinical leader, taking a similar approach to the way Benner (1984) has theorised in her staging of novice to expert clinical nurse.  相似文献   
89.
These consensus guidelines provide recommendations for the safe handling of monoclonal antibodies. Definitive recommendations are given for the minimum safe handling requirements to protect healthcare personnel. The seven recommendations cover: (i) appropriate determinants for evaluating occupational exposure risk; (ii) occupational risk level compared with other hazardous and non‐hazardous drugs; (iii) stratification of risk based on healthcare personnel factors; (iv) waste products; (v) interventions and safeguards; (vi) operational and clinical factors and (vii) handling recommendations. The seventh recommendation includes a risk assessment model and flow chart for institutions to consider and evaluate clinical and operational factors unique to individual healthcare services. These guidelines specifically evaluated monoclonal antibodies used in the Australian cancer clinical practice setting; however, the principles may be applicable to monoclonal antibodies used in non‐cancer settings. The guidelines are only applicable to parenterally administered agents.  相似文献   
90.
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