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This retrospective study examined the clinical course of 18 prepubertal boys (aged 6 to 12) who had dual diagnoses of attention deficit hyperactivity disorder and conduct disorder and who received clonidine on an inpatient basis after failed trials of conventional drug therapy, consisting predominantly of psychostimulants. The effects of clonidine were assessed during inpatient treatment and after discharge at intervals of 1 to 2 months. Eleven (61%) of the children had marked improvement as measured by clinical impression. Transient sedation lasting 2 to 3 days occurred after initial administration or dosage increase; otherwise, clonidine was well tolerated. Our findings suggest that clonidine may prove to be an alternative treatment of comorbid attention deficit hyperactivity disorder and conduct disorder.  相似文献   
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OBJECTIVE: Primary aortoenteric fistula is a rare disorder of which only four patients have been reported in the Dutch literature so far. The objective of our study was to obtain more realistic figures on the incidence of this condition, with data on the clinical presentation, diagnostic procedures, treatment and results in a group of patients not previously reported as "case histories". METHODS: A questionnaire was sent to all surgical clinics in The Netherlands. Out of 180 questionnaires, 102 have been returned reporting 27 patients to which data of eight others treated in our own institution were added. RESULTS: In all but one of these 29 patients the fistula was caused by an atherosclerotic aneurysm, the one exception being caused by an ingested cocktail pin. Gastrointestinal haemorrhage was the predominant symptom, being present in 28 of the patients, while the complete triad of haemorrhage, pain and a pulsating mass was found in only eight patients. Twenty-seven patients were treated with an in situ graft of which 14 are doing well at long term follow-up. CONCLUSIONS: Primary aortoenteric fistula is far more common than one would expect from the number of patients reported in literature. A high index of suspicion based on a complete physical examination remains the key to a correct diagnosis. Direct closure of the intestine and in situ grafting of the aorta is the treatment of first choice.  相似文献   
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Biomarkers have enormous potential to improve patient care by establishing tests of diagnosis, prognosis, and treatment effects. Successfully translating a biomarker from discovery to clinical application demands high-quality discovery research and high-quality clinical studies for biomarker validation; however, there are additional challenges that face biomarker research in pediatrics. There are also additional characteristics of pediatric medicine that make biomarker research especially needed. This review focuses on the fundamentals of biomarkers, the additional considerations needed for applying biomarker research to children, and recommendations for advancing pediatric biomarker research.  相似文献   
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A linear recursive procedure is one each of whose executions activates at most one invocation of itself. When linear recursion cannot be replaced by iteration, it is usually implemented with a stack of size proportional to the depth of recursion. In this paper we analyze implementations of linear recursion which permit large reductions in storage space at the expense of a small increase in computation time. For example, if the depth of recursion isn, storage space can be reduced to \(\sqrt n \) at the cost of a constant factor increase in running time. The problem is treated by abstracting any implementation of linear recursion as the pebbling of a simple graph, and for this abstraction we exhibit the optimal space-time tradeoffs.  相似文献   
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Terminal chromosome associations ("satellite associations") in ASG-banded preparations have been used to determine the number and location of staellites in the Syrian hamster (Mesocricetus auratus) and the Djungarian hamster (Phodopus sungorus). Five pairs of satellites are found in the former and four in the latter. Nucleolar organizing regions (NORs) were visualized with the Ag-AS silver precipitation technique, and their number and position corresponded exactly with the number and position of satellites in Phodopus, where positive chromosome identification can be made in the absence of banding. Numerical agreement is exact in Mesocricetus as well, and the morphology of the silver-tagged NOR-bearing chromosomes strongly suggests that corrrespondence also occurs in this species.  相似文献   
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A comparison of self-report vs. observer rating of depressed mood in a heterogenous inpatient population revealed wide variations in concordance among diagnostic groups. Patients diagnosed as having Affective Psychosis and "Other' illnesses showed the highest correlation between four self-report scales and an observer rating scale. Patients with a diagnosis of depressive Neurosis showed only modest correlation, while Schizophrenics revealed no significant correlation, on these instruments, suggesting inconsistent communication of affect from Schizophrenic patients to observers. In contrast, when self-report scales were intercorrelated, patients in all four diagnostic categories showed highly significant correlations, indicating that they were consistently reporting their affective state on these instruments. The implications of these findings for future research as well as for practical clinical management are discussed.  相似文献   
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