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Neuregulin 1 (NRG1) is one of the most exciting candidate genes for schizophrenia since its first association with the disorder in an Icelandic population. Since then, many studies have analyzed allele and haplotype frequencies in European and Asian populations in cases and controls yielding varying results. We investigated the association of NRG1 with psychosis in a total sample set of 575 individuals from 151 Spanish nuclear families. We tested eight SNPs across 1.2 Mb along NRG1 including regions previously associated to schizophrenia in association studies. After correction for multiple testing, the TDT analysis for each marker did not show a significant over-transmission of alleles from the parents to the affected offspring for any of the markers (P > 0.05). The haplotypic analysis with TRANSMIT and PDT did not show preferential transmission for any of the haplotypes analyzed in our sample. These results do not seem to suggest that the investigated NRG1 markers play a role in schizophrenia in the Spanish population, although the finding of a trend for association with one SNP in the 3'of the gene warrants further investigation.  相似文献   
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BACKGROUND: Lipid transfer proteins (LTPs) are major allergens of Rosaceae fruits in the Mediterranean area. IgE-cross-reactivity has been demonstrated in vitro among LTPs from peach, apple, chestnut and Artemisia pollen. The aim of this study was to evaluate the reactivity to LTPs from peach, apple, chestnut and Artemisia pollen by means of skin prick tests (SPTs). METHODS: Forty-seven patients allergic to peach (peach group), 20 patients sensitized to Artemisia pollen with no food allergies (Artemisia group), and 12 control subjects were skin tested with fresh peach, as well as with whole extracts and purified LTPs of peach, apple, chestnut and Artemisia pollen. RESULTS: The rates of positive SPTs for peach, apple, chestnut and Artemisia LTPs were, respectively, 91, 77, 23, and 36% in the peach group, and 30, 5, 15 and 40% in the Artemisia group. No response was observed in the control subjects. SPTs with peach LTP strongly correlated with SPTs conducted with fresh peach. In the peach group, the most frequent pattern of reactivity to LTPs was the combination peach-apple (45%), followed by peach-apple-Artemisia-chestnut (21%). Significant correlations were found between peach and apple LTPs, and between Artemisia and chestnut LTPs. Positive SPTs to chestnut LTP were only observed in patients with positive SPTs to Artemisia LTP. All the patients with positive case histories to chestnut reacted to chestnut LTP. CONCLUSIONS: LTPs are plant panallergens with different patterns of cross-reactivity. They are major allergens of Rosaceae fruits and seem to be involved in allergic reactions to unrelated foodstuffs such as chestnut, probably through sensitization to the cross-reactive Artemisia LTP. Rosaceae LTPs could be useful tools for in vivo diagnosis of Rosaceae fruit allergy.  相似文献   
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To document the epidemiology, clinical features, and outcomes of murine typhus patients in the Canary Islands (Spain), we analyzed data that were retrospectively collected for 16 years for 221 patients. Murine typhus in the Canary Islands is characterized by a high rate of complications (31.6%), mainly liver, lung, kidney or central nervous system involvement.  相似文献   
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Abstract: The present study investigated the effects of dopamine on the canine external carotid circulation. One min. intracarotid artery (i.c.) infusions of dopamine (10–310 μg min.?1) produced dose‐dependent decreases in the canine external carotid conductance without affecting blood pressure or heart rate. This effect was mimicked by the D1/2‐like receptor agonist apomorphine (1–310 μg min?1), but not by the D2‐like receptor agonist, bromocriptine (31–310 μg min.?1). In contrast, fenoldopam (1–310 μg min.?1, intracarotid), a D1‐like receptor agonist, produced dose‐dependent increases in external carotid conductance. The vasoconstrictor response to dopamine was abolished after intravenous administration of the antagonists, phentolamine (α1/2; 2000 μg kg?1) or rauwolscine (α2; 100 μg kg?1), but remained unaffected after prazosin (α1; 100 μg kg?1) or haloperidol (D2‐like; 1000 μg kg?1). Interestingly, after phentolamine not only were the vasoconstrictor responses to dopamine abolished, but even a dose‐dependent vasodilator component was unmasked. These vasodilator responses to dopamine remained unchanged after intravenous haloperidol or propranolol (1000 μg kg?1 each). On the other hand, the vasodilator responses to fenoldopam, which remained unchanged after intravenous saline (0.1 ml kg?1), propranolol (1000 μg kg?1) or vagosympathectomy, were abolished by the D1‐like receptor antagonist, SCH‐23390 (10 μg kg?1). Lastly, the responses to dopamine and fenoldopam were not significantly altered after intraperitoneal pretreatment with reserpine (5 mg kg?1; ?24 hr). The above results suggest that the canine external carotid vasoconstrictor responses to dopamine: (i) are mainly mediated by α2‐adrenoceptors; and (ii) overshadow a vasodilator component, which involves vascular D1‐like receptors.  相似文献   
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Human exposure to and contamination by environmental toxic compounds generates discourses and practices that merit greater attention. In this article, we assess internal chemical contamination and the risk of toxic effects as an experience related to the production of meaning in everyday life. Drawing on the analysis of semantic networks of narratives from semi-structured interviews conducted with 43 informants in Catalonia, Spain, we consider participants’ perceptions of the health risks of toxic compounds, including social discourses on exposure, toxicity, and internal chemical contamination, and on responsibilities, consequences, and proposed strategies for controlling toxic compounds. Informants’ narratives on the relationships between nature and nurture suggest that they no longer perceive rigid boundaries separating the human body from the external environment and its chemical pollutants.  相似文献   
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ObjectiveTo describe the use of the Internet by primary care patients to seek health related information, understand how they are influenced by this information, and evaluate its impact on the doctor-patient relationship.DesignCross sectional study, through self-administered survey.SettingOne urban health center in Madrid.ParticipantsA total of 323 questionnaires were collected from patients between 14 and 75 years old who attended a physician's office for any reason, excluding illiterate patients and those with neurological or psychiatric problems preventing them from completing the survey.MeasurementsInternet usage, ability of the internet to clarify doubts regarding health issues, patient lifestyle changes, socio-demographic variables, and physician's receptivity to the use of internet by patients.Results61% (CI 95%: 56%-67%) of patients used the Internet as a source of health information: Internet queries were able to address health doubts in 92.4% of users, 53.5% reported that the Internet changed their thinking about their health in at least one instance, 30% made behavioral changes (of which 60.1% discussed these changes with their physician), 44.3% had more questions at the physician's office, and 80.8% believe that the doctor would be willing to talk about the information found on the internet.ConclusionsUsing the Internet to find information about health is very common, with positive influence on physician-patient relationship. This may be useful for achieving behavioral changes in patients and can be used as a tool in medical practice.  相似文献   
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BACKGROUND: The diagnostic significance of a tilt table test (TTT) in patients with a suspected arrhythmic etiology for syncope and negative electrophysiologic study (EPS) has not been previously assessed comparing the TTT results with the findings of prolonged monitoring using an implantable loop recorder (ILR). We sought to assess the diagnostic yielding of TTT in patients with suspected arrhythmic syncope and negative EPS. METHODS AND RESULTS: In 81 patients with suspected arrhythmic etiology for syncope and negative EPS, TTT was performed and an ILR implanted regardless the results of TTT. TTT was positive in 38 patients. During follow-up, syncope or presyncope recurred in 32 patients (39.5%). No differences were found in recurrence rates in patients with positive and negative TTT (31.5% vs 46.5%, P = ns). According to rhythm registered during ILR activation, mechanisms of syncopal events were classified as: arrhythmic (atrioventricular [AV] block and ventricular tachycardia; n = 18), neurally mediated (sinus bradycardia and sinus pause; n = 9), and indeterminate (normal sinus rhythm; n = 5). There was no statistical association between the results of TTT and the mechanism of syncope. CONCLUSIONS: In patients with a suspected arrhythmic etiology for syncope and a negative EPS, TTT is of little value to predict the mechanism of syncope and the ILR implantation seems to be a useful and safe diagnostic strategy.  相似文献   
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