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81.

Objective

Caustic substance ingestion is a public health issue in some underdeveloped countries. Published information on socio-demographic factors related to this problem is scarce. The aim of this study was to evaluate the association of socio-demographic factors with caustic ingestion in children.

Methods

Design: case-control study. Cases were children with caustic substance ingestion who were attended to during 2006 (n = 94) at a pediatric referral hospital in Guadalajara, Mexico; the controls were a random sample of children who were hospitalized or seen as outpatients in the same pediatric referral hospital (n = 641). The socio-demographic variables were studied using a validated questionnaire (Children Nutrition Organization Survey). Statistics: OR, 95% CI and logistic regression.

Results

Mean age of the cases was 3.2 years (SD 2.4) and 37.2% of cases were girls. Caustic ingestion occurred at home in 63.8% of cases and at a relative's home in 23.4% of cases. Alkaline products were ingested by 85.1%; containers had no warning labels in 72.3% of cases and no childproof safety caps in 92.6% of cases. The socio-demographic variables associated with caustic ingestion included higher family income, lower educational level of the mother, higher proportion of fathers working as independent professionals, extended family, mother's age <30 years, and mother working outside the home.

Conclusions

The observed family risk profile for caustic ingestion was higher family income, young working mother with low educational level, father working as independent professional, and extended family.  相似文献   
82.
Human parasitosis is still prevalent worldwide and causes significant morbidity and mortality in developing countries. The involvement of the lung is variable depending on the characteristics of the parasites and hosts. In malnourished and immunodeficient children, the consequences of lung parasitosis may result in significant morbidity and mortality.  相似文献   
83.
Endogenous interleukin-12 (IL-12) mediates protection against Yersinia enterocolitica in C57BL/6 mice by triggering gamma interferon (IFN-γ) production in NK and CD4+ T cells. Administration of exogenous IL-12 confers protection against yersiniae in Yersinia-susceptible BALB/c mice but exacerbates yersiniosis in resistant C57BL/6 mice. Therefore, we wanted to dissect the different mechanisms exerted by IL-12 during Yersinia infections by using different models of Yersinia-resistant and -susceptible mice, including resistant C57BL/6 mice, susceptible BALB/c mice, intermediate-susceptible wild-type 129/Sv mice, 129/Sv IFN-γ-receptor-deficient (IFN-γR−/−) mice and C57BL/6 tumor necrosis factor (TNF) receptor p55 chain-deficient (TNFR p55−/−) mice. IFN-γR−/− mice turned out to be highly susceptible to infection by Y. enterocolitica compared with IFN-γR+/+ mice. Administration of IL-12 was protective in IFN-γR+/+ mice but not in IFN-γR−/− mice, suggesting that IFN-γR-induced mechanisms are essential for IL-12-induced resistance against yersiniae. BALB/c mice could be rendered Yersinia resistant by administration of anti-CD4 antibodies or by administration of IL-12. In contrast, C57BL/6 mice could be rendered more resistant by administration of transforming growth factor β (TGF-β). Furthermore, IL-12-triggered toxic effects in C57BL/6 mice were abrogated by coadministration of TGF-β. While administration of IL-12 alone increased TNF-α levels, administration of TGF-β or TGF-β plus IL-12 decreased both TNF-α and IFN-γ levels in Yersinia-infected C57BL/6 mice. Moreover, IL-12 did not induce toxicity in Yersinia-infected TNFR p55−/− mice, suggesting that TNF-α accounts for IL-12-induced toxicity. Taken together, IL-12 may induce different effector mechanisms in BALB/c and C57BL/6 mice resulting either in protection or exacerbation. These results are important for understanding the critical balance of proinflammatory and regulatory cytokines in bacterial infections which is decisive for beneficial effects of cytokine therapy.  相似文献   
84.
PURPOSE: To report the efficacy of primary retrobulbar chlorpromazine injections for the management of blind and seeing painful eyes. PATIENTS AND METHODS: Retrospective case series from three university hospitals was done. Twenty eyes of 20 patients with at least 3 months of follow-up are reported. Ten of these 20 eyes did not receive any other ophthalmic medications either 2 weeks before chlorpromazine injection or at any time point after injection. Treatment was considered successful if pain control lasted for at least 3 months, without the need for reinjection or enucleation. RESULTS: Sixteen of 20 (80.0%) eyes achieved successful pain control. There were no permanent complications in any patient. CONCLUSIONS: Retrobulbar chlorpromazine appears to be safe and effective for the management of pain in blind eyes.  相似文献   
85.
BACKGROUND: With survival rates for people with head and neck (H&N) cancers static during the past 30 years and the enormous burden of psychosocial impacts they suffer well documented, the testing of psychosocial interventions in this group is a priority. OBJECTIVE: To test the feasibility of providing a psycho-educational intervention for people with H&N cancer. METHODOLOGY: A prospective non-randomised design was used. Subjects were patients with H&N cancer. They were offered the Nucare coping strategies program in one of three formats: small group and one-to-one formats with therapists; and a home format, with material for home use, without a therapist. Outcomes measures (quality of life (QOL) and anxiety and depression) were collected at baseline and following the intervention. Analyses were performed using non-parametric statistics. RESULTS: Of 128 people invited to participate, 66 agreed, 59 completed the intervention and 50 had outcomes data. Following the intervention, there were significant improvements in physical and social functioning and global QOL, and reduced fatigue, sleep disturbance and depressive symptoms. CONCLUSIONS: These data suggest that the intervention is desired by the target group, feasible to deliver after cancer therapy and may have some beneficial effects, although an appropriately designed study is required to confirm this.  相似文献   
86.
OBJECTIVE: To examine foetal lung blood perfusion using power Doppler ultrasound (PDU) and to compare fractional moving blood volume (FMBV) and mean pixel intensity (MPI) estimations in the lungs of normally grown (NG) foetuses and foetuses with intrauterine growth restriction (IUGR) and also to correlate foetal lung FMBV and MPI with respiratory complications after birth. METHODS: Lungs of 47 NG and 25 IUGR foetuses after 32 weeks of gestation were examined with PDU. FMBV and MPI were estimated in a defined region in the posterior part of the foetal lung closest to maternal abdominal wall. FMBV and MPI were correlated to foetal weight deviation and gestational age. Perinatal outcome and respiratory complications after birth were recorded in both groups. RESULTS: There were significantly lower FMBV and MPI values in IUGR than in NG foetuses. The overall variation was lower for FMBV than for MPI. There was a slightly higher correlation between FMBV and foetal weight deviation [r = 0.33, 95% confidence intervals (CI) 0.11-0.52] than between MPI and foetal weight deviation (r = 0.26, 95% CI 0.03-0.46). There was no significant correlation between FMBV or MPI and gestational age. No differences between the groups were found in the rate of respiratory complications, and they were not correlated either to the FMBV or MPI. CONCLUSION: FMBV and MPI, estimated from the PDU signals of foetal lung circulation, showed lower values in third-trimester pregnancies complicated by IUGR. The frequency of neonatal respiratory complications was not increased in cases with low pulmonary FMBV and MPI values.  相似文献   
87.
4-(N-Methyl-N-nitrosamino)-1-(3-pyridyl)-1-butanone (NNK), the tobacco-specific nitrosamine, induces lung cancer in all animal species tested and is thought to contribute significantly to the high lung cancer burden associated with smoking. However, there is no report whether NNK could promote colon cancer growth. To address this hypothesis and the possible signaling pathways involved, we used SW1116 colon cancer cell line to study these biological events in vitro. Results showed that NNK, after 5-h treatment, stimulated cell proliferation, enhanced alpha7-nicotinic acetylcholine receptor (alpha7-nAChR) mRNA levels and nuclear factor-kappaB (NF-kappaB) DNA binding activity, as well as 5-lipoxygenase and cyclooxygenase-2 protein expressions. alpha-Bungarotoxin, the specific alpha7-nAChR antagonist, inhibited these biological effects. However, 5-lipoxygenase inhibition had no effect on alpha7-nAChR mRNA expression, but significantly inhibited cell proliferation and activation of NF-kappaB and cyclooxygenase-2, whereas NF-kappaB-specific inhibitor caffeic acid phenethyl ester reduced both cell proliferation and cyclooxygenase expression induced by NNK without affecting alpha7-nAChR mRNA level and 5-lipoxygenase expression. Together, the present study demonstrated that NNK promoted colon cancer growth in vitro. NF-kappaB not only conveys the biological effect of alpha7-nAChR activation but is also involved in the cross-talk between 5-lipoxygenase and cyclooxygenase-2 in response to NNK in colon cancer cell development.  相似文献   
88.
20-year follow-up of a patient with coronary artery spasm   总被引:1,自引:0,他引:1  
The authors present a 20-year follow-up of a patient with well-documented coronary artery spasm, who initially presented with syncope. The patient had excellent response to calcium channel antagonists and long-acting nitrates.  相似文献   
89.
In the present study, a polymer-encapsulated plasminogen activator was investigated as an alternative to restore blood flow more effectively than free plasminogen activator. While current fibrinolytic agents have limited efficacy, attributable to delayed onset of sustained reperfusion and bleeding complications, encapsulated plasminogen activators have shown promise in addressing these shortcomings. A polymer-encapsulated plasminogen activator could offer an effective formulation with a prolonged shelf-life. In this study, coronary artery thrombosis was produced in the anesthetized dog by the injection of thrombin + whole blood, and then one of five randomly selected formulations was administered intravenously: saline, blank microcapsules, free streptokinase (FREE SK), streptokinase and blank microcapsules (FREE SK + BLANK), or streptokinase entrapped in polymer microcapsules (MESK). MESK significantly accelerated the time to reperfusion compared to FREE SK or FREE SK + BLANK. Additionally, substantial reductions were observed in residual clot mass, infarct mass, reocclusion episodes, fibrinogen depletion and blood loss with MESK compared to FREE SK. The results of this study demonstrate that MESK accelerates thrombolysis and the restoration of blood flow compared to identical dosages of FREE SK while also reducing systemic fibrinogenolysis and blood loss. Microencapsulation may produce an improved dosage form for restoring arterial blood flow and reducing bleeding complications with thrombolytic therapy.  相似文献   
90.
Over the last few years, research on learning and memory has become increasingly interdisciplinary. In the past, theories of learning, as a prerogative of psychologists, were generally formulated in purely verbal terms and evaluated exclusively at the behavioral level. At present, scientists are trying to build theories with a quantitative and biological flavor, seeking to embrace more complex behavioral phenomena. Pavlovian conditioning, one of the simplest and ubiquitous forms of learning, is especially suited for this multiple level analysis (i.e., quantitative, neurobiological, and behavioral), in part because of recent discoveries showing a correspondence between behavioral phenomena and associative properties at the cellular and systems levels, and in part because of its well established quantitative theoretical tradition. The present review, examines the mayor quantitative theories of Pavlovian conditioning and the phenomena to which they have been designed to account. In order to provide researchers from different disciplines with a simple guideline about the rationale of the different theoretical choices, all the models are described through a single formalism based on the neural network connectionist perspective.  相似文献   
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