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131.
OBJECTIVES: This study examined how immunization-related beliefs, attitudes, and perceived control mediate up-to-date immunization among various sociodemographic groups. METHODS: Statewide estimates of immunization rates among children up to the age of 2 years were obtained via a multistage cluster sample. In-person interviews were conducted with 4832 parents. Information about immunization was obtained from official records or from health care providers. RESULTS: Differences in immunization among sociodemographic groups were mediated by beliefs about objective barriers to immunization, protection, medical contraindication, safety concerns, distrust, and natural immunity. Protection beliefs contributed to positive attitudes toward immunization; beliefs in natural immunity and safety concerns contributed to negative attitudes. Beliefs about objective barriers, distrust, safety concerns, and medical contraindications influenced perceived control over immunization. Positive attitudes and a strong sense of control contributed to higher immunization rates. CONCLUSION: These findings provide a basis for efficient educational campaigns by specifying which beliefs should be bolstered (because they facilitate proper immunization) and which should be targeted for change (because they hinder proper immunization) in various sociodemographic groups. 相似文献
132.
The prevalence of elevated blood lead (PbB) levels in rural and semi-urban areas of Kwazulu/Natal (KZN) as well as the risk factors for elevation of PbB among children in informal settlements are examined. The study involved over 1200 children in two age groups: 3-5 and 8-10 years old. Average PbB level in Besters, an informal settlement in the Durban metropolitan region, was 10 micrograms/dl with 5% of the children showing PbB level of greater than 25 micrograms/dl. By comparison, average PbB value in Vulamehlo, a rural area located 90-120 km from Durban, was 3.8 micrograms/dl and 2% of the PbB was greater than 10 micrograms/dl. The results show that many children in KZN are at risk of being lead poisoned. Household factors that were significantly associated with PbB levels in children included distance from tarred roads, overcrowding, hygienic habits in the household and the burning of solid wastes for heating or cooking. Lack of significant association with child risk behaviors is attributed to the over-riding influence of high levels of contaminated dusts both indoor and outdoor. With recent introduction of unleaded gasoline in South Africa, a number of unique socio-ecological factors are expected to slow the change in PbB levels of children in some townships. 相似文献
133.
134.
PURPOSE: Our previous research indicated that the exposure of rat pups to an hypoxic environment during a discrete developmental period (postnatal days 10-15) produces short-term seizures and confers an enduring increase in susceptibility to pentylenetetrazol- and flurothyl-induced seizures. In this study, we evaluated the effects of hypoxic insult in this neonatal period of susceptibility to electrical kindling and corneal electroconvulsive shock. METHODS: Ten-day-old rat pups were exposed to a 3% O2 environment, as previously described, and were either kindled or exposed to corneal electroshock at adulthood (70 days old). RESULTS: Neither kindled seizure development from the septal nucleus or amygdala nor electroconvulsive shock profiles were significantly altered by hypoxic pretreatment. CONCLUSIONS: Results indicate that hypoxia produces increases in seizure susceptibility that are observable in only some experimental seizure models but not in others. This outcome serves to target some anatomic systems more than others in the mechanisms involved in hypoxia-induced neural reorganization. 相似文献
135.
A Pizziol V Tikhonoff CD Paleari E Russo A Mazza G Ginocchio C Onesto L Pavan E Casiglia AC Pessina 《Canadian Metallurgical Quarterly》1998,52(11):846-849
BACKGROUND: Leishmaniasis recidiva cutis (LRC) is rare in New World leishmaniasis. Only seven cases have been reported so far. MATERIALS AND METHODS: Four cases are reported here. Parasite diagnosis was performed by classical methods of touch preparations, histopathologic sections, and cultures. In addition, the detection of parasite DNA by the polymerase chain reaction (PCR) was performed in all cases. RESULTS: Parasites were detected by at least one of the classical methods in all primary lesions; however, only the PCR was positive in the recidivant lesions. DISCUSSION: LRC cases most likely represent a reactivation of an initial infection, probably due to the persistence of parasites in scarred tissue. Although lupoid leishmaniasis (LL) has been used as a synonym of LRC, a clear difference between LRC and LL can be defined as LL is the initial clinical presentation while LRC is a recurrent lesion. CONCLUSIONS: The results indicate that it is not appropriate to use these two denominations as synonyms. The designation of LRC should be maintained in order to define recidives occurring at the border of an old scar of cutaneous leishmaniasis, avoiding the confusion with the lupoid form of the disease. 相似文献
136.
STUDY OBJECTIVE: To evaluate the cross-reactivity of dapsone after a documented hypersensitivity reaction to trimethoprim-sulfamethoxazole (TMP-SMX) during prophylaxis for Pneumocystis carinii pneumonia. DESIGN: Retrospective, chart review, cohort study. SETTING: Two university-affiliated teaching hospitals. PATIENTS: Sixty patients infected with the human immunodeficiency virus. MEASUREMENTS AND MAIN RESULTS: Thirteen patients (21.7%) had cross-reactivity to dapsone after the reaction to TMP-SMX. No significant risk factors for this response were identified. Most reactions were of mild or moderate severity and rated as possibly or probably caused by one of the agents. Of the 13 patients, 4 (30.8%) continued therapy. CONCLUSIONS: Although cross-reactivity can occur, dapsone may be considered in patients with mild hypersensitivity reactions to TMP-SMX. 相似文献
137.
Blocked signal transduction to the ERK and JNK protein kinases in anergic CD4+ T cells 总被引:1,自引:0,他引:1
T cells activated by antigen receptor stimulation in the absence of accessory cell-derived costimulatory signals lose the capacity to synthesize the growth factor interleukin-2 (IL-2), a state called clonal anergy. An analysis of CD3- and CD28-induced signal transduction revealed reduced ERK and JNK enzyme activities in murine anergic T cells. The amounts of ERK and JNK proteins were unchanged, and the kinases could be fully activated in the presence of phorbol 12-myristate 13-acetate. Dephosphorylation of the calcineurin substrate NFATp (preexisting nuclear factor of activated T cells) also remained inducible. These results suggest that a specific block in the activation of ERK and JNK contributes to defective IL-2 production in clonal anergy. 相似文献
138.
PC Fletcher PJ McKenna CD Frith PM Grasby KJ Friston RJ Dolan 《Canadian Metallurgical Quarterly》1998,55(11):1001-1008
BACKGROUND: Functional neuroimaging experiments have implicated prefrontal cortex (PFC) in memory processes. Several studies of schizophrenic patients have shown failure of activation in the dorsolateral region of PFC (DLPFC). We used a graded memory challenge to characterize functional neuroanatomical differences between schizophrenic and control subjects. The graded manipulation of task demands enabled us to assess group differences in the context of normal and abnormal psychological task performance. METHODS: Memory-related activity was assessed using positron emission tomography in schizophrenic patients and age-matched controls during performance of a graded memory task. Subjects underwent scanning while learning and recalling word lists of variable length. RESULTS: We used a model that assessed linear and nonlinear effects of memory load. Nonlinear group differences in DLPFC activation were observed. Controls showed a steepening slope of DLPFC increase as task demands increased. By contrast, schizophrenic subjects showed initial DLPFC increases that fell away with increasing memory load. The DLPFC response in schizophrenic subjects was closely related to measured task performance. In addition, schizophrenic subjects failed to show task-related decreases in activity in the left superior temporal and inferior parietal gyrus. CONCLUSIONS: Patients with schizophrenia showed a failure in DLPFC activation only in the face of diminished performance measures, suggesting that a full characterization of task-related changes in DLPFC activation must consider performance levels. However, striking failures of deactivation in superior temporal and inferior parietal regions were independent of task performance, possibly reflecting a core abnormality of the condition. 相似文献
139.
The clinical features and family histories of 20 adults with dyskinetic cerebral palsy from 20 families were studied. The majority of the patients showed progressive neurological deterioration in adult life. In only three did the condition stabilise by 10 years of age and in seven there was deterioration after the age of 30. Two patients developed a secondary cervical spondylotic myelopathy. Four patients had affected relatives and there were similar proportions of affected parents and siblings. The family data suggest genetic heterogeneity with autosomal recessive and dominant variants. The existence of an X-linked form cannot be excluded, and the demonstration of an increased paternal age effect among single cases suggests that some of these may arise because of fresh dominant genetic mutation. 相似文献
140.