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61.
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Abstract

An inhibition enzyme-linked immunosorbent assay was used to detect infectious pancreatic necrosis (IPN) virus. In this assay the presence of virus was determined by measuring the decrease in titer of a known antiserum after incubation with a sample suspected to contain virus. The titer of the antiserum was measured with an indirect enzyme-linked assay. Compared to the double antibody sandwich method this assay required fewer reagents (only one anti- IPN serum was required). This assay was also sensitive enough to detect virus at levels of 1×102 TCID50/ml. of purified virus and was able to detect virus in samples obtained in the field.  相似文献   
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The new echocardiographic techniques for the study of physiopathological intramyocardial phenomena include video densitometry (VD), integrated backscatter (IBS), and color Doppler myocardial imaging (CDMI). Being more independent from cardiac load and from rotational and translational heart motion, these new sensible, noninvasive techniques such as CDMI and IBS show a real incremental value in comparison with conventional echocardiography and allow to detect subtle functional and textural abnormalities of intramural myocardium, partially undetectable by conventional two-dimensional Doppler echocardiography. Subclinical thyroid dysfunction (STD), both in its hypo- and hyperthyroidism form, has a relatively high prevalence in general population (9–15% with a lower percentage of adult males), hence it could be very useful to study more deeply heart involvement in these physiopathological conditions and understand the complex relationship between thyroid and heart. The use of these new ultrasonic techniques in subclinical hypothyroidism helps to detect the early simultaneous involvement of both cardiac cycle phases, which causes a decrease of intramyocardial contractility and an impairment of both active and passive phases of diastole. In subclinical hyperthyroidism, these new ultrasonic techniques permitted to discover more complex and different early cardiac abnormalities of both systolic and diastolic phases.  相似文献   
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The effects of silymarin on bronchoconstriction induced by antigen challenge and on post-antigen challenge hyperresponsiveness to substance P were evaluated in sensitized guinea-pigs. Silymarin significantly decreased the bronchoconstriction due to antigen administration in the early phase of the response. In contrast, the dose-response curve for substance P recorded 1 h after antigen challenge was not modified by pretreatment with silymarin. The influence of the flavonoid on hyperresponsiveness to histamine in propranolol- and PAF (platelet-activating factor)-treated animals was also assessed. Silymarin did not affect hyperresponsiveness to histamine induced by either propranolol or PAF although it had inhibitory activity on the bronchial contractile response to the autacoid. These results suggest that silymarin has a protective effect in the early phase of allergic asthma, an effect, which may be related to a negative influence of the flavonoid on bronchial responsiveness to histamine.  相似文献   
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The aims of the study were to examine the relationship between long-chain polyunsaturated fatty acid (LCPUFA) status at diagnosis of phenylketonuria (PKU) and neurodevelopment through the first 12 months of life, and to assess whether any difference exists between infants breastfed and bottlefed in the first days of life on the basis of LCPUFA status. Twenty infants with PKU were prospectively examined through the first year of life. Plasma fatty acids were measured in infants at diagnosis. Plasma phenylalanine levels were determined monthly. Main outcome measures were the Bayley Mental Developmental Index (MDI) and Psychomotor Developmental Index (PDI) at 5 and 12 months of age, and the visual function at 12 months, evaluated by P100 wave latencies with visual evoked potentials. A higher PDI score was associated with higher plasma arachidonic acid at diagnosis (adjusted correlation coefficient of PDI at 5 months, r=0.38, p=0.05). P100 wave latency at 15 minutes of arc (15') was associated with the early plasma arachidonic acid (adjusted r=-0.56, p=0.02) and phenylalanine levels at 12 months (adjusted r=0.22, p=0.05). No association was found between MDI score and any essential fatty acids. Breastfed infants exhibited higher plasma arachidonic acid (mean difference, delta, =3.4%; 95% confidence interval [CI]=1.2-5.6%) and shorter P100 wave latency at 15' (delta=-21 ms, 95%CI=-30 to -12) than bottlefed infants. Within the population of this study, a weak positive association has been found between plasma LCPUFAs at diagnosis (higher in breastfed infants) and neurodevelopmental indices through the first year of life.  相似文献   
69.
This article resulted from a survey carried out by some researchers of the Telefono Verde AIDS (TVA-National AIDS Help-Line) of the Istituto Superiore di Sanità, with the collaboration of some colleagues of the Segreteria per le Attività Culturali. It is also a summary of strategies of intervention against HIV/AIDS for young people implemented by the Italian Ministry of Health. The study was developed within the context of the workshops on HIV/AIDS education carried out since 1995 by some researchers of TVA. These workshops fall within some other initiatives arranged by the Segreteria per le Attività Culturali for the diffusion of scientific and technological information. Our study aimed at assessing the level of knowledge on HIV/AIDS among some different high-school students. Data processing points out a widespread and quite good level of knowledge on HIV/AIDS in general and particularly on ways of transmission and prevention measures. Results obtained could not be generalized because the sample involved in the survey represented a privileged target, already sensitive to the issues concerning HIV infection and AIDS dealt with in the context of specific teaching programmes.  相似文献   
70.
This study examined relationships among perceived stress, self-esteem, acculturation, and gender with the coping response of 472 Mexican American adolescents aged 14 to 16 years. Subjects were drawn from a predominantly Mexican American population located in the Lower Rio Grande Valley region of Texas. Data were collected through a self-report instrument consisting of perceived stress, acculturative status, self-esteem, and coping strategy scales. Subjects reported relatively high perceived stress levels, low acculturation, and moderate self-esteem scores with no significant gender differences. Analysis revealed self-esteem as most predictive of a more effective overall coping response. Results suggest Mexican American adolescents possessing high self-esteem are less likely to encounter damage to their sense of self when confronted with stressors, thus allowing for productive coping.  相似文献   
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