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81.
82.

Background  

Persistent stimulation of cardiac β1-adrenergic receptors by endogenous norepinephrine promotes heart failure progression. Polymorphisms of this gene are known to alter receptor function or expression, as are polymorphisms of the α2C-adrenergic receptor, which regulates norepinephrine release from cardiac presynaptic nerves. The purpose of this study was to investigate possible synergistic effects of polymorphisms of these two intronless genes (ADRB1 and ADRA2C, respectively) on the risk of death/transplant in heart failure patients.  相似文献   
83.
84.
Parabens are used extensively in personal care products; however, their estrogenic properties have raised concern over risks to human health. High levels of total parabens, mainly as conjugates, have been reported in human plasma/serum, with limited data on native parabens. Our objective was to assess and link plasma concentrations of native common parabens to self-reported use of personal care products in women from the general population. The information was obtained from an extensive questionnaire on diet and lifestyle previously answered by the women in the NOWAC study. Plasma samples from 332 individuals were extracted and cleaned up by automated solid phase extraction and analyzed by ultra high performance liquid chromatography time-of-flight mass spectrometry. Native methyl paraben dominated and was detected in 63% of the samples, with a median level of 9.4 ng/ml. Ethyl paraben (median < 3 ng/ml) and propyl paraben (median < 2 ng/ml) were detected in 22 and 29%, respectively. Butyl and benzyl parabens were not detected. For the first time, elevated levels of native parabens are reported in women from the general population. The concentrations were significantly associated with the use of skin lotions, indicating that frequent (daily or more) use maintain elevated concentrations despite the parabens short half-lives. These findings clearly emphasize the need to study potential health effects in the general population.  相似文献   
85.
86.
Background and purpose:  The frequency of different Charcot–Marie–Tooth (CMT) genotypes has been estimated in clinic populations, but prevalence data from the general population are lacking. Methods:  Our population‐based genetic epidemiological survey included persons with CMT residing in eastern Akershus County, Norway. The participants were interviewed and examined by one geneticist/neurologist and classified clinically, neurophysiologically and genetically. Results:  Two hundred and forty‐five persons from 116 families had CMT. This corresponds to 1 per 1214 persons (95% CI 1062–1366) have CMT in the general population. CMT1 (motor conduction velocity (MCV) <38 m/s), CMT2 (MCV >38 m/s) and CMT intermediate (MCV 25–45 m/s) were found in 48.2%, 49.4% and 2.4% of the families. A total of 27.2% of the families and 28.6% of the affected had a mutation in the investigated CMT genes. The prevalence of the peripheral myelin protein 22 (PMP22) duplication and point mutation in the connexin32 (Cx32), myelin protein zero (MPZ) and mitofusin2 (MFN2) genes was found in 13.6%, 6.2%, 1.2%, 6.2% of the families, and in 19.6%, 4.8%, 1.1%, 3.2% of the affected, respectively. None of the families had point mutations in the early growth response 2 (EGR2), PMP22 or small integral membrane protein of lysosome/late endosome (SIMPLE) genes. Conclusions:  CMT is the most common inherited neuropathy. At present, 43 CMT genes are known, and an examination of all known genes would probably only identify mutations in approximately 50% of those with CMT. Thus, it is probable that at least 30–50 CMT genes are yet to be identified.  相似文献   
87.
88.

Background  

Seafarers play an important role in the transmission of communicable diseases. The aim of the present study is to draw information and identify possible gaps on occupational health practices related to seafarers sailing on ships within the European Union Member States (EU MS) with focus on communicable diseases.  相似文献   
89.
In addition to established indications in non‐melanoma skin cancer in immunocompetent patients, photodynamic therapy (PDT) has been studied for the treatment, and possible prevention, of superficial skin cancers in immunosuppressed patients. As a topical photosensitizer can be applied over large areas, PDT is also increasingly used for field cancerization in photodamaged skin, with evidence of potential to delay the development of actinic keratoses and basal cell carcinoma, although direct evidence of prevention of invasive squamous cell carcinoma remains limited. PDT has been studied in patch/plaque‐stage cutaneous T‐cell lymphoma, with efficacy more likely in unilesional disease. Accumulating evidence supports the use of PDT in acne and several other inflammatory/infective dermatoses including cutaneous leishmaniasis, although protocols are still to be refined. Despite proven efficacy, PDT is not widely used in viral/genital warts, where pain during treatment can be intense. PDT is a therapeutic option for photorejuvenation, with improvement in fine wrinkles, mottled hyperpigmentation, roughness and sallowness reported.  相似文献   
90.
Interleukin‐12 (IL‐12) has previously been suggested as playing a major rôle in the activation of cytotoxic lymphocytes. Recent reports indicate that cytotoxic CD8+ cells are critically involved in the elicitation phase of contact hypersensitivity reactions. In this study, the in situ expression of IL‐12 was investigated in normal human skin and in allergic contact dermatitis by immunohistochemistry. Skin biopsy specimens were obtained from allergic patch test reactions after 3 days, and from normal skin in 8 subjects. In contrast to normal skin, a strong enhancement of IL‐12 immunoreactivity was observed in the mononuclear cell infiltrate of allergic contact dermatitis. IL‐12 immunoreactivity was mainly located in the cytoplasm of dermal dendritic cells and macrophages as well as of some Langerhans cells. IL‐12‐positive cells were often found in close apposition to lymphocytes. Furthermore, positive immunostaining was also detected in keratinocytes at sites of marked exocytosis and spongiosis in the epidermis. In conclusion, the enhanced in situ expression of IL‐12 may contribute to the activation of cytotoxic lymphocytes and thereby represent an important factor in the pathogenesis of contact hypersensitivity reactions in humans.  相似文献   
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