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Brazil nuts are the second most frequent cause of nut allergy in the United Kingdom. We report the case of a 20-year-old woman with documented Brazil nut allergy who developed widespread urticaria and mild dyspnea after intercourse with her boyfriend who had earlier consumed Brazil nuts. Skin prick testing with the boyfriend's semen after Brazil nut consumption confirmed significant reactivity whereas a sample before nut consumption was negative. We believe this to be the first case of a sexually transmitted allergic reaction.  相似文献   
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The leaf essential oil of Eugenia zuchowskiae from Monteverde, Costa Rica, has been obtained by hydrodistillation and analyzed by GC–MS. The principal constituents of E. zuchowskiae leaf oil were α-pinene (28.3%), β-caryophyllene (13.2%), α-humulene (13.1%), and α-copaene (8.1%). The leaf essential oil of E. zuchowskiae showed pronounced in-vitro cytotoxic activity against MCF-7, MDA-MB-468, and UACC-257 human tumor cell lines. The major components showed cytotoxic activities comparable to doxorubicin (LC50 14–70 μg/ml).  相似文献   
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A gradual reduction in cell-mediated immunity is thought to occur with the progression of human immunodeficiency virus (HIV) infection. This suggests a selective attrition of the Th1 subset. The regulation of the soluble form of the low-affinity receptor for IgE (sCD23) by the opposing actions of interleukin-4 (IL-4) and interferon-gamma (IFN-gamma) allows the assessment of the overall balance of Th1 to Th2 activity in a given disease. In order to investigate this further we employed an enhanced chemiluminescent ELISA to analyse serum levels of sCD23 in male subjects with and without HIV infection. Serum levels of sCD23 were similar in 34 HIV seronegative homosexuals, 39 homosexuals with asymptomatic HIV infection, 27 homosexuals with acquired immune deficiency syndrome (AIDS) and 20 healthy controls. This suggests that HIV has no predilection for either the Th1 or Th2 subsets of CD4 T cells.  相似文献   
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BACKGROUND: The treatment of hepatitis C virus (HCV)-related cirrhosis is difficult due to high frequency of adverse effects. We retrospectively reviewed the case records of patients with HCV cirrhosis to evaluate the efficacy and tolerability of pegylated (peg) interferon and ribavirin treatment in these patients. METHODS: Medical records of 28 patients with HCV-related compensated cirrhosis were reviewed. The treatment protocol was a combination therapy of peg interferon alfa-2b (1 microg/Kg/week) plus oral ribavirin (10-12 mg/Kg/day). Primary endpoint was sustained virological response, with additional endpoints of drug tolerance, clinical or biochemical worsening and death. RESULTS: End-of-treatment virlogic response was seen in 24 of 28 patients (85%) and sustained virologic response in 15 of 28 (53%) patients. Biochemical end-of-treatment response and sustained response were seen in 20 and 16 patients (71% and 57%), respectively. Treatment had to be stopped in 3 patients due to decompensation of liver status in two and drug intolerance in one, while dose modification was required in two patients. CONCLUSIONS: Combination therapy with peg interferon plus ribavirin seems effective in patients with liver cirrhosis. High relapse rate, poor biochemical recovery and possibility of decompensation are issues that need to be kept in mind.  相似文献   
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MR thermometry techniques based on the strong water 1H signal provide high spatial and temporal resolution and have shown promise for applications such as laser surgery and RF ablation. However, these techniques have low temperature sensitivity for hyperthermia applications and are greatly influenced by local motion and susceptibility variations. 1H NMR signals from paramagnetic lanthanide complexes of Pr3+, Yb3+ and Tm3+ show up to 300-fold stronger temperature dependence compared to the water 1H signal. In addition, 1H chemical shifts of many of these complexes are insensitive to other factors such as the concentration of the paramagnetic complex, pH, [Ca2+], and the presence of plasma macro-molecules and ions. Applications of lanthanide complexes for temperature measurement in intact animals and the feasibility of mapping temperatures in phantoms have been demonstrated. Among all the lanthanide complexes examined so far, thulium 1, 4, 7, 10-tetramethyl-1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetate (TmDOTMA-) appears to be the most attractive for in vivo MR thermometry. The 1H signal from the methyl groups on this complex is relatively intense because of 12 equivalent protons and provides high temperature sensitivity because of the large paramagnetic shifts induced by thulium. The possibility of imaging TmDOTMA2--in intact animals at physiologically safe concentrations has recently been demonstrated. Overall, MR thermometry methods based on hyperfine-shifted MR signals from paramagnetic lanthanide complexes appear promising for animal applications, but further studies relating to acceptable dose and signal-to-noise ratio are necessary before clinical use.  相似文献   
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