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21.
The insecticidal activity of five alkylfurans against the generalist insect herbivore beet armyworm, Spodoptera exigua, was examined. Two naturally occurring compounds, the avocadofurans 2-(pentadecyl)furan (1) and 2-(heptadecyl)furan (2), previously isolated from specialized avocado idioblast oil cells, and three homologues, 2-(tetradecyl)furan (3), 2-(hexadecyl)furan (4), and 2-(octadecyl)furan (5), were synthesized. Bioassays of alkylfurans 1-5 using a 9-day diet-incorporation initiated with neonates showed that all alkylfurans tested significantly increased S. exigua larval mortality and reduced larval weights, with maximal biological activity detected among the naturally occurring alkylfurans 1 and 2.  相似文献   
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BACKGROUND: It has recently been suggested that primary lactase deficiency might have been selected for by malaria, as occurred for beta-thalassaemia and glucose 6-phosphate dehydrogenase deficiency. However, recently we have found that the prevalence of primary lactase deficiency in the area of Sassari (Northern Sardinia), where, in the past, there was intermediate malarial endemicity, is comparable to that observed in the adult population from other areas of Southern Italy where malaria was less endemic. AIMS: To address the problem further, we have determined the prevalence of primary lactase deficiency, glucose 6-phosphate dehydrogenase deficiency deficiency and beta-thalassaemia trait in the populations of three Sardinian villages which differ in altitude above sea-level, socioeconomic features, history of endemic malaria and prevalence of b-thalassaemia and glucose 6-phosphate dehydrogenase deficiency. SUBJECTS: We tested 138 adult males: 53 were from Fonni (a non-malarial mountain village, with a strong pastoral tradition), 38 from Lodé (a village with a similar pastoral tradition, but high malarial endemicity in the past) and 47 from Terralba (a lowland fishing village with an agricultural tradition and heavy malarial morbidity and mortality). METHODS: A blood sample was obtained in all subjects for determination of HbA2 and glucose 6-phosphate dehydrogenase activity. Lactase deficiency was assessed by measuring breath hydrogen production after oral administration of lactose (50 g), by gas-chromatography. RESULTS: The frequencies of glucose 6-phosphate dehydrogenase deficiency and of beta-thalassaemia trait in the non-malarial village of Fonni were strikingly low, compared to frequencies found in the two villages (Terralba and Lodé) with a very high past malarial morbidity. In contrast, there was no significant difference in the prevalence of lactase deficiency in the three groups of subjects from the three villages. CONCLUSIONS: These data obtained in Northern Sardinia do not support the hypothesis of a selection of primary lactase deficiency by malaria. For definitive conclusions, however, the malaria hypothesis should be tested in other parts of the world.  相似文献   
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A Spanish-language questionnaire designed for measuring the impact of asthma on quality of life in adults was developed. It was derived, by the application of a rigorous translation protocol, from a previously validated, English-language Asthma Quality of Life (AQL) questionnaire which had been developed in Australia. The aim of this study was to evaluate the psychometric properties of the Spanish AQL questionnaire using a cross-sectional and longitudinal design. Two hundred ninety-four clinically stable subjects with asthma (168 women, mean baseline forced expiratory volume in 1 sec [FEV1] = 85% predicted), aged 17-70, attended for the initial baseline assessment. All subjects completed the AQL questionnaire and a full history and physical examination were performed. The clinical assessment of severity was based on the classification recommended by the Global Initiative on Asthma (GINA). One week after the initial assessment subjects completed the AQL questionnaire for a second time. Six months later, subjects were assessed clinically and completed all the assessment measures at baseline. Principal components analysis of the AQL questionnaire responses at the baseline visit revealed a structure that was almost identical to that seen in the original English-language questionnaire. The questionnaire was shown to be internally consistent (Cronbach's alpha 0.91 for total score and 0.80-0.86 for the four subscales) and repeatable (intraclass correlation coefficient 0.91 for the total scale and 0.78-0.92 for the subscales). The finding of expected strong correlations with the subject's global assessment of severity (p = 0.70) and dyspnea (p = 0.63), a weak inverse correlation with FEV1 (p = -0.17), and good discrimination among the four GINA severity categories (F3,291 = 37.16, p < 0.0001) supports the construct validity of the questionnaire. AQL scores increased with age (p = 0.31) and were higher in women (p < 0.005). The AQL was responsive to both improvement (mean change 1.02, p < 0.0001) and deterioration (mean change -1.13, p < 0.001) in the severity of asthma over a 6-month period. This disease-specific, Spanish-language AQL questionnaire was shown to have sound psychometric properties which make it suitable for use in cross-sectional or longitudinal studies where it is appropriate to assess the impact of asthma on the quality of life of individual patients.  相似文献   
24.
Histopathologic studies have demonstrated microshards from silicone elastomer metatarsophalangeal joint implants in adjacent tissues in a setting of chronic inflammation and in inguinal lymph nodes. Cytologic smears of synovial fluid from symptomatic implanted joints should show these refractile, nonpolarizing microshards in the reactive inflammatory context. Nonspecific enzymatic inflammatory activity contributes to further destabilization of the implants, eventuating in symptoms and signs requiring prosthesis removal. Cytopathologic examination of aspirated fluid from the vicinity of a symptomatic implanted joint demonstrates foreign body reaction to silicone elastomer, predicting a need for intervention before the local damage is severe and disabling.  相似文献   
25.
The action of duck egg drop syndrome 1976 (EDS-76) adenovirus on model bilayer lipid membranes (BLM) has been investigated on planar egg phosphatidylcholine membranes and small unilamellar vesicles. It was found that the adenovirus formed channels in planar BLM in a pH-dependent manner. The addition of EDS-76 to planar BLM at pH 5 induced voltage-independent channel activity of about 60 pS conductivity after a lag phase. At pH 3, EDS-76 induced irregular spikes of current across the planar BLM which disappeared after several minutes. The adenovirus also was able to induce pH-dependent leakage of calcein-loaded liposomes. EDS-76 did not induce channel activity in planar BLM or liposome leakage at neutral pH.  相似文献   
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After intracameral injection calcitonin gene-related peptide has been demonstrated to break the blood aqueous barrier and increase intraocular pressure in rabbits. However in cats, calcitonin gene-related peptide decreases intraocular pressure by increasing the outflow facility of aqueous humor. In the present study, the effect of intracameral injection of calcitonin gene-related peptide on the outflow facility in rabbits has been investigated and the intraocular pressure and outflow facility were measured following intravitreal administration of calcitonin gene-related peptide. The results demonstrate that in spite of the apparent pseudofacility component caused by a breakdown of the blood aqueous barrier also the true trabecular outflow is probably increased in the rabbit eye after intracameral injection of calcitonin gene-related peptide. The intravitreal administration of calcitonin gene-related peptide leaves the blood aqueous barrier intact and causes an increase in the outflow facility of aqueous humor with a concomitant long-lasting decrease in intraocular pressure.  相似文献   
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