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21.
The association between executive function (EF; planning, working memory, and inhibition) and individual differences in symptoms of attention deficit hyperactivity disorder (ADHD) was explored in a sample of preschool children. One hundred sixty children (between the ages of 3 years, 0 months and 5 years, 6 months), selected so as to oversample high ADHD scorers, performed 3 tasks previously shown to measure planning (Tower of London), working memory (Noisy Book) and inhibition ("Puppet Says..."). EF measures were reliable (kappa > .77) and were correlated with IQ (rs > .38) and age (rs > .59). Once IQ and age were controlled, planning and working memory (r = .41) were correlated. Planning and working memory were not correlated with inhibition (rs < .20). There was no association between ADHD and working memory or planning (rs < .12). There was a significant negative association between ADHD and conduct problems and inhibition (r = -.30 and r = -.25, respectively). Only the link with ADHD persisted after the effects of other factors were controlled for in a multiple regression. Specific deficits in inhibitory control rather than general EF deficits are associated with ADHD in the preschool period. This association is linear in nature, supporting the idea that ADHD is better seen as a continuum rather than a discrete category. This association provides evidence for Barkley's (1997) view that ADHD is underpinned by inhibitory deficits in the preschool period.  相似文献   
22.
A new enzyme-linked fluorescence assay (ELFA) suitable for use with peroxidase-antibody conjugates is described. The substrate for the assay is p-hydroxyphenylacetic acid, the fluorescent product of which is stable and unaffected by light. The assay compared favourably with a standard ELISA for the quantitation of IgM antibodies to hepatitis B core antigen.  相似文献   
23.
Chronic Azithromycin (AZM) is a common treatment for lung infection. Among adults at risk of cardiac events, AZM use has been associated with cardiovascular harm. We assessed cardiovascular safety of AZM among children with CF, as a secondary analysis of a placebo-controlled, clinical trial, in which study drug was taken thrice-weekly for a planned 18 months. Safety assessments using electrocardiogram (ECG) occurred at study enrollment, and then after 3 weeks and 18 months of participation. Among 221 study participants with a median of 18 months follow-up, increased corrected QT interval (QTc) of ≥30 msec was rare, at 3.4 occurrences per 100 person-years; and incidence of QTc prolongation was no higher in the AZM arm than the placebo arm (1.8 versus 5.4 per 100 person-years). No persons experienced QTc intervals above 500 msec. Long-term chronic AZM use was not associated with increased QT prolongation.  相似文献   
24.
Highly effective CFTR modulator drug therapy is increasingly available to those with cystic fibrosis. Multiple observational research studies are now being conducted to better understand the impacts of this important therapeutic milestone on long-term outcomes, patient care needs, and future research priorities. PROMISE is a large, multi-disciplinary academic study focused on the broad impacts of starting elexacaftor/tezacaftor/ivacaftor in the US population age 6 years and older. The many areas of investigation and rationale for each are discussed by organ systems, along with recognition of remaining important questions that will not be addressed by this study alone. Knowledge gained through this and multiple complementary studies around the world will help to understand important health outcomes, clinical care priorities, and research needs for a large majority of people treated with these or similarly effective medications targeting the primary cellular impairment in cystic fibrosis.  相似文献   
25.
Structure and receptor binding   总被引:42,自引:0,他引:42  
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26.
Hormones are believed to play a dominant role as promoters in the growth and development of hormone-dependent cancers. Much less is known about the circulating hormones in male patients with oesophageal cancer. This lack of attention led us to evaluate the role of peptide and steroid hormones (by RIA) in male patients with oesophageal cancer (n=49). Blood samples of patients were collected pretherapeutically and data was compared with age matched controls (n=25). In this retrospective study, significantly high levels of FSH (P<0.02), LH (P<0.001) and prolactin (P<0.001) were observed with concomitant low levels of estradiol (P<0.001), DHEA-S (P<0.02) and testosterone (P<0.001) in patients when compared with respective controls. The patients when grouped according to anatomical site and histological type of the tumor, intergroup variation was not observed in these hormones. From our, study, it seems that hormonal imbalance or altered ratio of peptide and steroid hormones might be playing a significant role in the development and/or progression of oesophageal carcinoma in men.  相似文献   
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Abnormal vestibular responses are observed more frequently in cerebellar and Brain stem lesions than in cerebello-pontine angle tumours. The direction of spontaneous, positional, positioning nystagmus or caloric induced directional preponderance are not quite reliable in topographical localisation of these lesions. Hyperreflexia and dysarhythmia of thermally induced nystagmus are reasonably reliable evidences of affections of cerebellum or its connections. The deficiency of the fast phase of nystagmus indicates a bulbopontine lesion.  相似文献   
29.
BACKGROUND: Hemodynamic lesions of the cervicocerebral vasculature are currently being treated with stent supported percutaneous transluminal angioplasty. These procedures have met with increasing success when compared to the risks and morbidity of more invasive surgical approaches. The versatility of stent-supported angioplasty as a primary therapeutic modality is examined in the following complex cases. CASE DESCRIPTION: We present four cases involving cervical angioplasty with emergent or adjunctive stent placement. Two cases involved the subclavian arteries, whereas the others involved the vertebral and internal carotid arteries. In our experience, complications of cervicocerebral artery angioplasty have been successfully managed by stent placement. CONCLUSION: Our cases demonstrate the emerging role of cervical angioplasty and stent implantation as a successful therapeutic modality, highlighted in these complex cases.  相似文献   
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