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11.
There is a paucity of published information available on extrapulmonary cryptococcosis (EC) in children infected with human immunodeficiency virus, the etiologic agent of the acquired immunodeficiency syndrome. We surveyed investigators in pediatric acquired immunodeficiency syndrome around the country regarding their experience with EC. Investigators from 33 (87%) of 38 institutions responded and information on 13 patients from 11 institutions was analyzed. EC was the acquired immunodeficiency syndrome indicator disease in 9 (69%) of 13 patients. Median age was 8 years with a range of 2 to 17 years. Human immunodeficiency virus risk factors were transfusion (5 patients), hemophilia (4 patients) and perinatal exposure (4 patients). Meningitis, seen in 62% of patients, was the most common clinical manifestation. Although 2 patients with fulminant disease died before therapy was started, 10 (91%) of 11 had a clinical response to amphotericin B with or without flucytosine. Our study indicates a spectrum of EC in pediatric human immunodeficiency virus infection ranging from fulminant, fatal fungemia to chronic meningitis and fever of unknown origin. Cryptococcosis was generally not the cause of death in patients who initially responded to amphotericin B therapy. Optimal antifungal therapy, including the role of fluconazole, warrants further study.  相似文献   
12.
Background Several clinical decision rules (CDRs) have been validated for pretest probability assessment of pulmonary embolism (PE), but the authors are unaware of any data quantifying and characterizing their use in emergency departments. Objectives To characterize clinicians' knowledge of and attitudes toward two commonly used CDRs for PE. Methods By using a modified Delphi approach, the authors developed a two‐page paper survey including 15 multiple‐choice questions. The questions were designed to determine the respondents' familiarity, frequency of use, and comprehension of the Canadian and Charlotte rules. The survey also queried the frequency of use of unstructured (gestalt) pretest probability assessment and reasons why physicians choose not to use decision rules. The surveys were sent to physicians, physician assistants, and medical students at 32 academic and community hospitals in the United States and the United Kingdom. Results Respondents included 555 clinicians; 443 (80%) work in academic practice, and 112 (20%) are community based. Significantly more academic practitioners (73%) than community practitioners (49%) indicated familiarity with at least one of the two decision rules. Among all respondents familiar with a rule, 50% reported using it in more than half of applicable cases. A significant number of these respondents could not correctly identify a key component of the rule (23% for the Charlotte rule and 43% for the Canadian rule). Fifty‐seven percent of all respondents indicated use of gestalt rather than a decision rule in more than half of cases. Conclusions Academic clinicians were more likely to report familiarity with either of these two specific decision rules. Only one half of all clinicians reporting familiarity with the rules use them in more than 50% of applicable cases. Spontaneous recall of the specific elements of the rules was low to moderate. Future work should consider clinical gestalt in the evaluation of patients with possible PE.  相似文献   
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For a prospective study of lead exposure and early development, we recruited pregnant women from a lead smelter town and from an unexposed town in Yugoslavia and followed their children through 7 years of age. In this paper we consider associations between lifetime lead exposure, estimated by the area under the blood lead (BPb) versus time curve (AUC7), and intelligence, with particular concern for identifying lead's behavioral signature. The Wechsler Intelligence Scales for Children-Version III (WISC-III) was administered to 309 7-year-old children, 261 of whom had complete data on intelligence, blood lead, and relevant sociodemographic covariates (i.e., Home Observation for the Measurement of the Environment (HOME), birth weight, gender, sibship size, and maternal age, ethnicity, intelligence, and education). These showed anticipated associations with 7-year intelligence, explaining 41-4% of the variance in Full Scale, Performance, and Verbal IQ. Before covariate adjustment, AUC7 was unrelated to intelligence; after adjustment, AUC7 explained a significant 2.8%-4.2% of the variance in IQ. After adjustment, a change in lifetime BPb from 10 to 30 micro/dl related to an estimated decrease of 4.3 Full Scale IQ points; estimated decreases for Verbal and Performance IQ were 3.4 and 4.5 points, respectively. AUC7 was significantly and negatively related to three WISC-III factor scores: Freedom from Distractibility, Perceptual Organization, and Verbal Comprehension; the association with Perceptual Organization was the strongest. Consistent with previous studies, the IQ/lead association is small relative to more powerful social factors. Findings offer support for lead's behavioral signature; perceptual-motor skills are significantly more sensitive to lead exposure than are the language-related aspects of intelligence.  相似文献   
15.
It was proposed that differences between paranoid and nonparanoid schizophrenics in the processing of affective information may reflect underlying differences in their schema for emotion-laden information. Performances of 14 paranoid schizophrenics, 13 nonparanoid schizophrenics, and 15 matched controls were compared on a facial affect judgment task, and a matched control task comprising geometric figures largely devoid of emotional information. Subjects were required to rate friendliness, select an emotion label, and subsequently to remember the stimuli. Nonparanoids were deficient in overall labeling of facial affect, suggesting a weak cognitive schema for emotional information. The paranoids were particularly more accurate than the nonparanoids at labeling the negative facial affects, suggesting well-developed negative emotional aspects in their cognitive schema. Unexpectedly, nonparanoids relative to paranoids displayed a greater memory deficit in the recognition of geometric figures than in the recognition of faces. The nonparanoid deficit suggests these subjects may have poorly organized schema for remembering less structured nonverbal information. The findings support the idea of fundamental cognitive processing differences between paranoid and nonparanoid schizophrenia.  相似文献   
16.
ABSTRACT: Given the increasing prevalence of schoolchildren's experience with crises and resulting loss through sudden or violent death, adoption of a school-based crisis prevention and response plan becomes crucial. This article reviews a model of regional, district, and school-based levels of response designed collaboratively by four school districts and consultants from Yale University. The team approach on which the model is based is examined through benefits it affords students, staff, parents, and the community. Obstacles that can impede full implementation of the model are identified, and strategies for overcoming logistical and systemic resistances are offered. This proactive design helps promote individual and organizational resiliency to traumatic events by promoting communication, collaboration, and service provision in an efficient and comprehensive manner.  相似文献   
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Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL.  相似文献   
19.
This article is an overview of the promotion function as a part of the ATM's marketing mix. It approaches various promotion decision areas from a managerial perspective, focusing upon some key components of promotion planning. Rather than provide specific operational or implementation details (how to write a brochure) it is more conceptual in nature and offers a framework for promotion planners. The article addresses promotion management, promotion objectives, analysis for promotion planning, the promotion mix, and addresses the benefits and limitations of some specific promotion tools available to the ATM manager. It treats ATMs as a service and reveals specific implications for promotion strategy dictated by services. The article also reports promotion tools employed by Alabama ATMs citing data from the Alabama study.  相似文献   
20.
Intracerebral vascular reactivity induced by the nitric oxide (NO) donor isosorbide dinitrate (IDN, 5 mg sublingually) is more major and longer-lasting in migraine patients who develop delayed headache in response to the drug. The headache is purportedly due to neuronally-mediated vascular mechanisms. Indomethacin inhibits prostaglandin synthesis, which is involved in NO generation. Indomethacin also decreases cerebral blood flow by constricting precapillary resistance vessels. In the present study, the hemodynamic effects of indomethacin were evaluated in migraine patients and healthy controls by means of transcranial Doppler monitoring. Indomethacin caused a significant decrease in mean flow velocity in the middle cerebral artery. This was an additional effect to the mean velocity decrease induced by IDN. The interactions between the two drugs suggest that their effects on cerebral hemodynamics (and pain) may be of relevance both in understanding the role of NO in migraine pathogenesis and in evaluating symptomatic treatments for migraine attacks.  相似文献   
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