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Attention deficit hyperactivity disorder (ADHD) is one of the most frequently diagnosed disorders in children, yet it remains poorly understood. Substantial controversy exists regarding correct diagnosis of ADHD, and areas of subjectivity in diagnosis have been identified. Concerns for appropriate diagnosis are critical in terms of children’s educational outcomes, as well as health concerns associated with the use and potential overuse of stimulant medications. There exists a relative-age effect in which children who are relatively younger than their peers and born closest to the school start age cut-off are more frequently diagnosed and treated for ADHD. Additionally, substantial variation exists in ADHD diagnosis between boys and girls, with boys often presenting with more stereotypical symptoms. Both the relative-age effect and variation in sex diagnosis, as well as the challenges of early preschool diagnosis, emphasize the importance of considering relative maturity in ADHD diagnosis of children. Implications and knowledge translation strategies for practitioners, parents and the education system are presented.  相似文献   
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BACKGROUND CONTEXT: The effectiveness of spinal surgery as a treatment option is currently evaluated through the assessment of patient-reported outcomes (PROs). The minimum clinically important difference (MCID) represents the smallest improvement considered worthwhile by a patient. The concept of an MCID is offered as the new standard for determining effectiveness of a given treatment and describing patient satisfaction in reference to that treatment. PURPOSE: Our goal is to review the various definitions of MCID and the methods available to determine MCID. STUDY DESIGN: The primary means of determining the MCID for a specific treatment are divided into anchor-based and distribution-based methods. Each method is further subdivided and examined in detail. METHODS: The overall limitations of the MCID concept are first identified. The basic assumptions, statistical biases, and shortcomings of each method are examined in detail. RESULTS: Each method of determining the MCID has specific shortcomings. Three general limitations in the accurate determination of an MCID have been identified: the multiplicity of MCID determinations, the loss of the patient's perspective, and the relationship between pretreatment baseline and posttreatment change scores. CONCLUSIONS: An ideal means of determining the MCID for a given intervention is yet to be determined. It is possible to develop a useful method provided that the assumptions and methodology are initially declared. Our efforts toward the establishment of a MCID will rely on the establishment of specific external criteria based on the symptoms of the patient and treatment intervention being evaluated.  相似文献   
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Ninety consecutive patients over a 6-month period with acute (31 patients) or chronic (59 patients) cholecystitis underwent a laparoscopic cholecystectomy on an ambulatory (49 patients), one-night (33 patients), or two-night (5 patients) basis. Three patients required open procedures for 1) perforated duodenal ulcer at 48 h, postoperatively, 2) a cholecystoduodenal fistula, and 3) Mirizzis syndrome with erosion of the common duct. The procedure is safe, efficacious, and should be offered to patients with acute and chronic biliary disease.  相似文献   
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A chimeric protein containing most of the hepatitis B virus preS2 region (amino acid residues 1–48) upstream to, and colinear with the amino-terminus of bluetongue virus VP7 protein (preS2VP7) was expressed by a recombinant Autographa californica nuclear polyhedrosis virus (AcNPV). The chimeric protein formed BTV core-like particles (CLPs) in Spodoptera frugiperda cells only when the cells were coinfected with this recombinant virus and a recombinant baculovirus that expresses unmodified VP7 and VP3 of BTV. The ratio of preS2VP7 incorporated into CLPs was influenced by the relative multiplicities of infection of the two viruses. Immunoelectron microscopy of the chimeric particles indicated that the preS2 epitope was exposed on the surface of the CLPs. When insect cells were coinfected with the preS2 VP7 recombinant virus and a baculovirus vector that synthesized only the VP3 protein, no CLPs were identified.  相似文献   
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On the basis of their observations in daily psychoanalytic work the authors developed five objective criteria for "bad" analytic hours. These criteria involve affect, intellectualization, isolation, lack of feedback, and dissatisfaction. The authors developed a formulation to help them preconsciously recognize the presence of these factors during therapeutic work and found that it was helpful in turning a potentially bad hour into a productive one.  相似文献   
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JC virus (JCV) is an ubiquitous human polyomavirus that frequently resides in the kidneys of healthy individuals and is excreted in the urine of a large proportion of the adult population. Polyomaviruses are associated with disease largely in immunocompromised individuals (progressive multifocal leukoencephalopathy). Colorectal cancers can show chromosome instability and it was hypothesized that JCV may account for some of this instability. We screened urine from 45 healthy donors and 233 colorectal cancer/normal tissue pairs for the presence of JCV sequences using a Taqman assay. This assay could detect 1 virus genome in 10 human genomes. In the urine samples, we found an infection rate of approximately 70%. The JCV isolates in these samples could be categorized into four JCV types (2B, 4, 7, and 8), none of which had a rearranged regulatory region. Among the colon tissues, one normal tissue (<0.5%) and none of the matched tumors tested positive for JCV. There is no evidence in these data to indicate that JCV is the cause of genetic instability in colorectal cancer.  相似文献   
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