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The co-occurrence of motor and imitation disabilities often characterises the spectrum of deficits seen in patients with autism spectrum disorders (ASD). Whether these seemingly separate deficits are inter-related and whether, in particular, motor deficits contribute to the expression of imitation deficits is the topic of the present study and was investigated by comparing these deficits’ cross-sectional developmental trajectories. To that end, different components of motor performance assessed in the Zurich Neuromotor Assessment and imitation abilities for facial movements and non-meaningful gestures were tested in 70 subjects (aged 6–29 years), including 36 patients with high-functioning ASD and 34 age-matched typically developed (TD) participants. The results show robust deficits in probands with ASD in timed motor performance and in the quality of movement, which are all independent of age, with one exception. Only diadochokinesis improves moderately with increasing age in ASD probands. Imitation of facial movements and of non-meaningful hand, finger, hand finger gestures not related to social context or tool use is also impaired in ASD subjects, but in contrast to motor performance this deficit overall improves with age. A general imitation factor, extracted from the highly inter-correlated imitation tests, is differentially correlated with components of neuromotor performance in ASD and TD participants. By developmentally fractionating developmentally stable motor deficits from developmentally dynamic imitation deficits, we infer that imitation deficits are primarily cognitive in nature.  相似文献   
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The aims of this study were to investigate whether intrafraction prostate motion can affect the accuracy of online prostate positioning using implanted fiducial markers and to determine the effect of prostate rotations on the accuracy of the software‐predicted set‐up correction shifts. Eleven patients were treated with implanted prostate fiducial markers and online set‐up corrections. Orthogonal electronic portal images were acquired to determine couch shifts before treatment. Verification images were also acquired during treatment to assess whether intrafraction motion had occurred. A limitation of the online image registration software is that it does not allow for in‐plane prostate rotations (evident on lateral portal images) when aligning marker positions. The accuracy of couch shifts was assessed by repeating the registration measurements with separate software that incorporates full in‐plane prostate rotations. Additional treatment time required for online positioning was also measured. For the patient group, the overall postalignment systematic prostate errors were less than 1.5 mm (1 standard deviation) in all directions (range 0.2–3.9 mm). The random prostate errors ranged from 0.8 to 3.3 mm (1 standard deviation). One patient exhibited intrafraction prostate motion, resulting in a postalignment prostate set‐up error of more than 10 mm for one fraction. In 14 of 35 fractions, the postalignment prostate set‐up error was greater than 5 mm in the anterior–posterior direction for this patient. Maximum prostate rotations measured from the lateral images varied from 2° to 20° for the patients. The differences between set‐up shifts determined by the online software without in‐plane rotations to align markers, and with rotations applied, was less than 1 mm (root mean square), with a maximum difference of 4.1 mm. Intrafraction prostate motion was found to reduce the effectiveness of the online set‐up for one of the patients. A larger study is required to determine the magnitude of this problem for the patient population. The inability in the current software to incorporate in‐plane prostate rotations is a limitation that should not introduce large errors, provided that the treatment isocentre is positioned near the centre of the prostate.  相似文献   
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A study was undertaken to determine the usefulness of ultrasonography as an investigative tool, and its role in deciding the management of Peyronie's disease. Fifteen patients with Peyronie's disease were studied by ultrasonography. The plaque could be demonstrated in all patients. The dimensions of the plaque varied from less than 1 cm to more than 7cm in length and 2-4mm in thickness. The disease was active in 26% of the patients, as indicated by the presence of hypoechoic areas around a central region of hyperechoism. Ultrasonogram was more accurate than clinical assessment in delineating the extent of lesions. In one-third of the patients, sonography demonstrated the plaques to be more extensive than had been detected by clinical examination. Calcification and activity of disease (which are clearly defined by ultrasonogram) are determining factors in the management of Peyronie's disease. This information allows the surgeon to select the modality of treatment, the timing of surgery and extent of excision. Thus, ultrasonography plays a vital role in the preliminary investigation and management of Peyronie's disease.  相似文献   
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An estimated 40% of US females now 14 years of age can be expected to experience pregnancy by age 19 years, and the majority of these pregnancies will be unintended. In 1981, there were 1,343,200 pregnancies among US females under 20 years of age and 448,570 abortions in this same age group. The abortion ratio is highest for adolescents under 15 years of age (1379 abortions/1000 live births), while the abortion rate is highest for 18-19 year olds (61.8/1000). When compared to adult women, adolescents obtain abortions at a later gestational age--a factor that increases both the psychological and medical risks of the procedure. Adolescents are also more likely than adults to base their decision regarding the pregnancy on the opinions of significant others. Comparative studies have shown teenagers who continue a pregnancy to have underdeveloped conceptualizations of the future, high levels of anxiety, and an external locus of control. Adolescents at greatest risk of psychological sequelae of abortion are those with pre-existing mental illness, strong religious beliefs, limited coping skills, a narrow support network, and abortion at later gestational stages. If the teenager feels pressured by her family to terminate the pregnancy, she is also at high risk for adverse psychological sequelae and a repeat pregnancy soon after abortion. Thus, counselors should maintain a neutral position while helping teens to examine the positive and negative aspects of their options. In terms of medical effects, teenagers have been shown to have the lowest risk of all age groups for abortion-related mortality. However, because of the later gestational age at which adolescents seek abortion, there is a higher risk of complications such as endometritis. Emphasis should be placed on expediting the abortion decision making process among adolescents to reduce delays and the potential risks.  相似文献   
26.
We report about 3 boys under 4 years of age with abdominal blunt trauma following child abuse admitted to our clinic with different diagnoses. Common were fresh or older haematomas, burn wounds, for which the parents had no plausible explanation. The children had no skeletal or intracranial lesions, but they developed abdominal pain, which became worse in the absence of the parents. X-ray and the clinical course lead us to laparatomy. In all cases we found lesions of the intestines, especially near the duodenojejunal flexure, hepatoduodenal ligament, root of the mesentery, mesocolon and retroperitoneum, in one case a pancrease rupture. All these lesions were caused by child abuse. We want to point out the problem in the diagnosis of battered child syndrome, especially of the abdominal blunt trauma.  相似文献   
27.
Clinical evaluation of biomarkers in Gaucher disease   总被引:1,自引:0,他引:1  
Novel or candidate biomarkers require thorough evaluation to establish their utility in a clinical setting. This paper describes an evaluation of several established enzyme markers of Gaucher disease and a newly-described chemokine, pulmonary and activation-regulated chemokine (PARC). The ability of the biomarkers to rank patients with Gaucher disease in order of disease severity and organ bulk, and to reflect changes in key clinical parameters in response to enzyme replacement therapy were evaluated. PARC concentrations were found to be reliably correlated with visceral disease and with key clinical responses to enzyme replacement in an unbiased manner. Unlike chitotriosidase and serum angiotensin-converting enzyme activity, genetic variation in serum PARC did not appear to influence its utility as a biomarker.
Conclusion: For each new candidate biomarker of lysosomal storage diseases, a similar clinical evaluation will be required, though the approach will need to be modified according to the clinical features and natural history of each disorder.  相似文献   
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Current evidence on the pathogenesis of Hirschprung's disease, then, favours the 'abnormal microenvironment' hypothesis wherein the developing and migrating normal neural crest cells confront a segmentally abnormal and hostile microenvironment in the colon. This hypothesis would account both for the congenital absence of ganglion cells in the wall of colon and also for the range of enteric neuronal abnormalities encountered including neuronal dysplasia, hypoganglionosis, and zonal aganglionosis. The abnormal constitution of the mesenchymal and basement membrane extracellular matrix in the affected segment of colon is presumably genetically determined and further understanding of the pathogenesis of this disorder will emerge as molecular geneticists characterise the specific genes and gene products associated with Hirschprung's disease. Advances in this field should permit gene probes to be developed to facilitate prenatal and postnatal diagnosis.  相似文献   
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