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91.
The electroretinograms (ERGs) of patients with Duchenne muscular dystrophy and an allelic variant of the mdx mouse (mdxCv3) have been shown to be abnormal. Analysis of five allelic variants of the mdx mouse with mutations in the dystrophin gene has shown that there is a correlation between the position of the mutation and the severity of the ERG abnormality. Three isoforms are expressed in the retina: Dp427, Dp260 and Dp71. Using indirect immunofluorescence and isoform-specific antibodies on retinal sections from three allelic mdx mouse strains, we have examined the localization of each of the isoforms. We show that Dp71 expression does not overlap with Dp427 and Dp260 expression at the outer plexiform layer (OPL). Instead, Dp71 is localized to the inner limiting membrane (ILM) and to retinal blood vessels. Moreover, we show that Dp260 and Dp71 differ structurally at their respective C-termini. In addition, we find that the proper localization of the beta- dystroglycan is dependent upon both Dp260 at the OPL and Dp71 expression at the ILM. Thus, Dp260 and Dp71 are non-redundant isoforms that are located at different sites within the retina yet have a common interaction with beta-dystroglycan. Our data suggest that both Dp71 and Dp260 contribute distinct but essential roles to retinal electrophysiology.   相似文献   
92.
SE Emmett  FJ Angus  JS Fry  PN Lee 《Allergy》1999,54(4):380-385
BACKGROUND: Despite increasing awareness of peanut allergy, little is known of its prevalence. We report on a two-stage interview survey conducted in Great Britain. METHODS: A total of 16434 adults (aged 15+ years) reported their own allergies and atopies and named cohabitants with peanut allergy (stage 1). Follow-up interviews were conducted with identified sufferers from peanut allergy (stage 2). RESULTS: At stage 1, peanut allergy was reported in 58 respondents and 205 other household members. When we accounted for cases where peanut allergy was unconfirmed or newly reported at stage 2, the prevalence, based on 124 confirmed sufferers, was estimated as 0.48% (95% confidence interval 0.40%-0.55%). The prevalence in children (0.61%, 0.41%-0.82%) was slightly higher than in adults; age-of-onset was strikingly earlier. Prevalence was strongly associated with other atopies, particularly tree-nut allergy. Cases tended significantly to cluster in households. Half of cases had never consulted a doctor. Exactly 7.4% reported being hospitalized after a reaction. CONCLUSIONS: Peanut allergy is reported by 1 in 200 of the population and is commoner in those reporting other atopies. The fact of similar rates in children and adults argues against a recent marked rise in prevalence. The frequency and potential lethality of this disorder emphasize the need for sufferers to demographic factors, other food allergies, atopic conditions, and allergy in family/household members. Our study comprised a screening survey and detailed interviews with sufferers identified. The frequency and potential lethality of this disorder emphasize the need for sufferers to receive correct medical advice on management [corrected].  相似文献   
93.
The aim of this study was to investigate the association between epilepsy and perinatal brain injury in a cohort of 610 infants born preterm at <33 weeks' gestation. The prevalence of epilepsy in this cohort was 4.3% as determined by a postal questionnaire survey. Most children with epilepsy (16 of 24) had high-risk cranial ultrasound lesions including haemorrhagic parenchymal infarction (HPI), posthaemorrhagic hydrocephalus, and cystic periventricular leukomalacia (PVL). Of all the children in our cohort with high-risk brain lesions, those with epilepsy were more likely to have HPI and significantly less likely to have cystic PVL, although it is possible that PVL was not noticed in some cases. Children with epilepsy and high-risk cranial ultrasound lesions also showed more cognitive impairment than children with high-risk lesions but no epilepsy, which suggested more cortical grey-matter damage. We suggest that brain injury has occurred outside the confines of the periventricular white matter in this group of preterm infants with epilepsy.  相似文献   
94.
95.
OBJECTIVE: To evaluate functional outcomes in a cohort of patients with juvenile dermatomyositis (DM). METHODS: A retrospective inception cohort of patients diagnosed as having juvenile DM between January 1, 1984 and January 1, 1995 was established at 4 Canadian tertiary care pediatric centers. Informed consent was obtained. Each subject was interviewed by telephone or in person. The primary outcome was physical function, as measured by the Childhood Health Assessment Questionnaire (CHAQ). Additional outcomes were educational and vocational achievement, growth, development of calcinosis, patient satisfaction with outcome, and development of other illnesses. Data regarding illness presentation, treatment, and disease course were obtained through chart review. RESULTS: Sixty-five of 80 patients (81%; 46 females and 19 males) could be contacted. The median followup time was 7.2 years (range 3.2-13.9 years), with a median age at followup of 13 years (range 7-26 years). Twenty-four patients (37%) had a monocyclic course, while the remaining 41 (63%) had a chronic continuous or polycyclic course. Sixty-two patients (95%) were treated with corticosteroids, while 41 (63%) received a second-line agent. Physical function was excellent, with a median CHAQ score of 0 (range 0-2.50). Eighteen patients had scores >0, and only 5 had moderate-to-severe disability, as defined by a CHAQ score >1.0. Females had higher CHAQ scores, and all but 1 of the patients with scores >0 were female (range 0-2.50; P = 0.015). Patients with a chronic continuous course also had higher CHAQ scores. Sixteen patients in the chronic continuous group had CHAQ scores >0 (range 0-2.50; P = 0.0009). Calcinosis developed in 22 patients (34%) and persisted to followup in 14. Development of calcinosis was not related to initial therapy, sex, or disease course, but was significantly associated with higher CHAQ scores (range 0-1.0 versus 0-2.5; P = 0.01). At the time of followup, 26 patients (40%) still had rash, 15 (23%) still reported weakness, and 23 (35%) continued taking medications, despite the fact that all were at least 3 years postdiagnosis. There was 1 death. CONCLUSION: In general, patients in this cohort had favorable outcomes. Most had CHAQ scores of 0, and only 8% met our definition of moderate-to-severe disability. However, many patients continued to have chronic disease, persistent rash, and continued taking medications >3 years after diagnosis. Further research is needed to improve outcomes for patients with juvenile DM.  相似文献   
96.
97.
OBJECTIVE: To assess the utility of the American College of Rheumatology guidelines for monitoring methotrexate (MTX)-related toxicity in a cohort of children with juvenile idiopathic arthritis (JIA). METHODS: Eighty-nine patients with JIA treated with MTX were monitored prospectively: aspartate aminotransferase (AST), alanine aminotransferase (ALT), complete blood count (CBC), and differential blood count were measured prior to starting MTX, and then monthly. Significantly abnormal blood tests (SABT) were prospectively defined as (1) significantly elevated liver enzymes (SELE) greater than twice the upper limit of normal; (2) granulocyte count < 1.5 109/l; (3) lymphocyte count < 0.9 109/l; or (4) hemoglobin decreased by > 2 g/l from previous level. Clinical interventions, current and cumulative MTX dose, duration of treatment, comorbidity, and concurrent medications at the time of the first SABT identification were recorded. Independent t tests and chi-squared tests were used for comparisons, and the probability of developing a SABT was calculated by Kaplan-Meier survival analysis. RESULTS: Forty percent of patients had a SABT: 26% had hematological abnormalities and 14% had SELE. Ninety-five percent of patients with SABT had symptoms consistent with a viral infection when the SABT was drawn and MTX dose was withheld until results had normalized on repeat testing. SABT persisting beyond one month occurred in only 2 patients, and their abnormalities resolved by 6 months with no specific identified cause; they resumed MTX at a later time without recurrence of SABT. There were no differences between patients with and without SABT with respect to current or cumulative MTX dose, duration of treatment, and concurrent medications at the time of the SABT. The probability of developing a SABT was estimated to be 11% at 3 months, compared to 10% probability of having an abnormal blood test by chance alone. CONCLUSION: Routine blood tests every 4 to 8 weeks in children with JIA are unnecessarily frequent.  相似文献   
98.
Background The major strategy for palliation of cyanotic lesions in neonates is the systemic to pulmonary arterial shunt. Methods Between May 1995, and December 2002, 48 consecutive neonates underwent systemic to pulmonary arterial shunts for cyanosis with reduced pulmonary blood flow. The mean age was 11.6 days (±SD 7.38) and the mean weight, 3.2kg (±SD 0.52). The babies were classified into three groups: Group I-Tetralogy-pulmonary Atresia (n=18), Group II-single Ventricle-Pulmonary atresia without (n=19) and with (n=5) isomerism, Group III-Pulmonary Atresia with Intact ventricular septum (n=6). Diagnosis was made by 2D echocardiography. Indication for cardiac catheterization was delineation of pulmonary anatomy/ductus laterality (n=4) or balloon atrial septostomy (n=4). The surgical procedure was a modified Blalock-Taussig shunt on the side of the situs. Post-operatively, no anti-coagulation or anti-platelet medication was employed. Results There was no mortality. Four cases required revision of the shunt in the immediate post-operative period for shunt thrombosis. The mean follow up was 17.54 months (±SD 8.36). In Group I, nine patients have undergone total correction with or without a conduit, while three required new arterial shunts for shunt/pulmonary artery stenosis. In Group II, nine patients have undergone bi-directional Glenn with atrial septectomy (n=2) and pulmonary artery plasty (n=4) and one patient underwent Fontan completion. In Group III, two patients underwent bi-directional Glenn and two had pulmonary valvotomy with/without right ventricular outflow tract widening. All the remaining babies are waiting for the second/final stage palliation or total correction. Conclusion Systemic to pulmonary arterial shunts in neonates is a gratifying and reasonably safe surgical procedure. Most babies become candidates for eventual univentricular/bi-ventricular repair.  相似文献   
99.
Aim: To determine the effectiveness of an interdisciplinary cognitive behavioural treatment for adolescents with chronic pain. Methods: Fifty seven adolescents (mean age 14.28 years) with chronic pain and 57 accompanying adults underwent an interdisciplinary three week residential programme of group cognitive behavioural therapy. Mean chronicity of pain was 4.02 years; 75% were absent from full time education (mean absence 17 months). Results: Post-treatment adolescents reported significant improvements for self report of disability (mean difference 3.37 (95% CI 0.65 to 6.09)), physical function (mean difference timed walk of 2.61seconds (1.02 to 4.2) and sit to stand of 3.22 per minute (0.79 to 5.65)). At three months post-treatment adolescents maintained physical improvements and reduced anxiety (mean difference 1.7 (0.72 to 2.67)), disability (mean difference 4.3 (1.44 to 7.17)), and somatic awareness (mean difference 4.43 (1.53 to 7.33)). Following treatment adults reported significant improvement in their report of adolescent disability (mean difference 4.43 (2.17 to 6.7)), adult anxiety (mean difference 1.73 (0.54 to 2.92)), depression (mean difference 1.16 (0.34 to 1.98)), and parental stress (mean difference 10.81 (2.91 to 18.78)). At three months significant improvements were maintained. At three months 64% improved school attendance; 40% had returned to full time education. Conclusions: Interdisciplinary cognitive behavioural pain management (with family involvement) is a promising approach to the management of pain, pain related distress, and disability.  相似文献   
100.
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