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91.
BACKGROUND: Studies of immigrants represent an useful tool to determine the relative relevance of environmental vs genetic factors in causing the reported rapid increase of the prevalence of sensitization and allergic diseases. METHODS: A total of 152 Albanian migrants to Southern Italy responded to a questionnaire based on the European Community Respiratory Health Survey (ECRHS) and 139 of them underwent skin prick test, and 61 serological assays for total IgE and IgG antibodies against Toxoplasma gondii (TG), herpes simplex virus 1 (HSV-1), hepatitis A virus (HAV) and Helicobacter pylori (HP). RESULTS: Reported asthma was rare (2/152; 1.3%) and reported nasal allergies rather frequent (24/152; 15.8%). Sensitization to common inhalant allergens occurred in 27/139 (19.4%) subjects. The frequency of skin sensitization to pollen (P = 0.003) and that of hay fever (P = 0.004) increased with the time spent in Apulia. All the 61 sera had antibodies against HAV, 59/61 (96.7%) against HSV-1, 48/61 (78.7%) against HP and 34/61 (55.7%) against TG. The prevalence of skin sensitization and hay fever symptoms were correlated to the duration of residence in Southern Italy. CONCLUSIONS: Data presented indicate that Albanian migrants to Italy, in spite of the low prevalence of allergic diseases and sensitization in their country of origin, manifest with time an increasing prevalence of sensitization to local allergens and nasal symptoms after immigration to Italy. This would suggest a permanent role of allergen exposure and lifestyle factors in influencing the appearance of sensitization and symptoms of allergic diseases.  相似文献   
92.
In the Zenica-Doboj Canton, 1106 hepatitis A virus (HAV) infections were reported during 2000 (an incidence rate of 252/100 000 population), with 996 (90.1%) cases occurring in nine community-wide outbreaks. Analysis of water supplies showed that 398 (19.1%) samples contained coliforms, including 202 (50.8%) that were contaminated with thermotolerant Escherichia coli. Sewage sanitation systems were absent or substandard in 53 910 (81.8%) rural households. The group most affected during outbreaks comprised children aged 7-14 years (incidence rate of 598/100 000). The development of health promotion and prevention initiatives in schools, combined with rigorous hygiene measures, will be necessary to achieve control of the spread of HAV.  相似文献   
93.
The anti-atherogenic effect of cholesteryl ester transfer protein (CETP) genetic variants associated with lowered enzyme activity is controversial. Moreover, in a few studies, this effect has been evaluated in the presence of a certain risk factor constellation. We addressed this issue in a case-control study, where 415 subjects with angiographically documented coronary artery disease (CAD +), 397 subjects without CAD (in 215, CAD was excluded by coronarography (CAD-)), and 188 healthy population controls, were screened for the CETP TaqIB polymorphism. The prevalence of the low-activity TaqIB2 allele was 0.396 in CAD+, and 0.428 and 0.416 in CAD- and population controls, respectively (p = 0.40). Its presence was significantly associated with increased high-density lipoprotein cholesterol (HDL-C) in population controls (1.40 +/- 0.40 mmol/l in B1B1, 1.52 +/- 0.39 mmol/l in B1B2 and 1.58 + 0.46 mmol/l in B2B2; p < 0.03 for trend), but not in the other groups. The CETP TaqIB polymorphism accounted for < 1% of the HDL-C variance in the whole cohort (p = 0.048). After adjustment for other risk factors, the CETP TaqIB2 allele was found not to be associated with significant changes in CAD risk independently of an assumed either dominant (odds ratio (OR) 0.97; 95% confidence interval (CI) 0.66-1.44; p = 0.89) or recessive effect (OR 0.68; 95% CI 0.42-1.12; p = 0.13). The CETP TaqIB polymorphism did not show a significant interaction with other risk factors in influencing CAD risk. Our findings do not support the hypothesis that a genetic variant resulting in lowered CETP activity is associated with reduced risk of coronary atherosclerosis.  相似文献   
94.
UV-light-induced signal cascades and skin aging   总被引:12,自引:0,他引:12  
  相似文献   
95.
Summary Forty men were tested with a computerized dynamometer for concentric and eccentric torques during arm flexion and extension at 0.52, 1.57, and 2.09 rad·s–1. Based on the summed concentric and eccentric torque scores, subjects were placed into a high strength (HS) or low strength (LS) group. The eccentric and concentric segments of the torque-velocity curves (TVCs) were generated using peak torque and constant-angle torque (CAT) at 1.57 and 2.36 rad. Angle of peak torque was also recorded. Compared to LS, HS had significantly greater estimated lean body mass (+ 10.2 kg) and approximately 25% greater average torque output. Reliability of the peak torque scores on 2 days in 20 subjects wasr0.85. The difference between observed torques and the mathematically computed criterion torque scores averaged 1% for three validation loads that ranged from 11.4 to 90.4 kg. Statistical analysis revealed that torque output in LS plateaued at low concentric velocities and was also flattened with increasing eccentric velocities. Conversely, torque ouptput for HS increased with decreasing concentric velocities and increased with increasing eccentric velocities. The method of plotting the TVCs for peak or CAT did not influence the pattern of TVC. Eccentric flexion peak torque occurred at a significantly shorter muscle length (1.88 rad) than concentric torque (2.12 rad). This difference was also present for extension; it was 1.88 rad for eccentric and 2.03 rad for concentric torque. These findings are discussed in terms of study design, neural inhibition, activation history, muscle-tendon elasticity, muscle fiber types, muscle architecture, and methodological considerations. The present results illustrate the importance of strength level to explain individual differences in TVC.  相似文献   
96.
ABSTRACT  Renal agenesis (RA) appears to be a multifactorial condition with combined genetic and environmental influences. We performed a retrospective case-control study of reproductive history of 26 isolated RA live births cases referred to Sicilian Registry of Congenital Malformations. A statistical significant association for birth weight if we considered all RA together and for bilateral RA alone, an increasing risk for maternal age only in the bilateral RA subgroup and a male predominance both for unilateral and bilateral RA was found. Our results show that some reproductive risk factors may be associated with RA, moreover differences found between subgroups indicate that some risk factors may be different in unilateral and bilateral RA. The association between reproductive risk factors and RA may reflect pathogenetic interaction between genetic and environmental factors. Nevertheless further studies are needed to clarify these associations and to explore the role of perinatal factors in the etiology of renal agenesis. In fact if prenatal or perinatal risk factors are in a causal chain influencing the risk for developing RA, then these data could have important implications in the prevention or treatment of this condition.  相似文献   
97.
Serological survey of human immunodeficiency virus (HIV) in Ethiopia   总被引:1,自引:0,他引:1  
The presence of anti-human immunodeficiency virus 1 antibodies was tested in 5,565 serum samples from Ethiopia of which 5,265 were collected from military recruits in the framework of a hepatitis B (HBV) seroepidemiological study performed on a national scale in 1985-1986; the remaining were 300 sera from a population of outpatients belonging to the Arsi region. Of the 5,565 sera, 121 (2.1%) were found to be repeatedly reactive by enzyme-linked immunosorbent assay (ELISA) test for HIV-1 antibodies, but these reactivities were confirmed by Western Blot (WB) assay in only four cases (0.07%) and by ENVACOR (confirmatory competitive ELISA) in three samples. Twenty-three sera were positive by WB to one or two bands related to core proteins but were all negative by ENVACOR. However, according to accepted criteria for positivity, these sera must be regarded as indeterminant reactors. A sample of 409 sera, both reactive and nonreactive by HIV-1 ELISA, were further tested for antibodies to HIV-2 by ELISA. Reactive sera were analysed by WB and by radioimmunoprecipitation assay (RIPA) using 35S-cysteine metabolically labelled SIVmac (HTLV-IV) infected cell lysates. Only 11 sera were found to be slightly reactive in ELISA, but this was not confirmed by WB or RIPA. Data indicate that HIV infection was not widespread in the general population of Ethiopia up to 1986.  相似文献   
98.
BACKGROUND: Few studies have looked at risk factors for asthma in African children. We aimed to identify the risk factors associated with childhood asthma in Maputo (Mozambique). METHODS: This case-control study included 199 age-matched children (100 asthmatic and 99 nonasthmatic) who attended Maputo Central Hospital between January 1999 and July 2000. We collected information concerning their familial history of atopy, birth weight, environment and breast-feeding. Detailed information about morbidity and treatment was obtained for each asthmatic child. RESULTS: The children were aged between 18 months and 8 years; 60% were male. The asthmatic children were hospitalized more frequently than the nonasthmatic children (P < 0.0001). Most of the asthmatic children lived in the urban area of Maputo [odd ratio (OR) = 6.73, CI = 3.1-14.0, P < 0.0001], had a parental history of asthma (OR = 26.8, CI = 10.8-68.2, P < 0.0001) or rhinitis (OR = 4, CI = 1.2-13.3, P = 0.005), had at least parent who smoked and were weaned earlier than the nonasthmatic children (OR = 2.4, CI = 1.3-4.4, P < 0.001). CONCLUSION: Childhood asthma was strongly associated with a family history of asthma and rhinitis, the place of residence, having smokers as parents and early weaning from maternal breast milk. These results highlight the need to reassess the management of asthmatic children in Maputo.  相似文献   
99.
The neurons containing somatostatin in the rat periventricular nucleus were studied by using a modified electron microscopic immunocytochemical technique that improves both the penetration of immunoreagents into unembedded immunostained tissues and the preservation of ultrastructural morphology. Inside perikarya and dendrites, immunostaining was not only associated with neurosecretory granules but also with ribosomes and saccules of the cis face of the Golgi apparatus. In the axonal profiles found in this region the labeling was observed both on neurosecretory granule cores and on the limiting membrane of small synaptic-like vesicles. Throughout the periventricular nucleus, both non-synaptic and synaptic relationships were shown between labeled neurons. Non-synaptic relationships mainly consisted of direct apposition of the membranes of neighboring neurons by dendrosomatic, somasomatic or dendrodendritic contacts. These labeled perikarya and dendrites were also synaptically contacted by labeled axonal endings containing numerous aggregated synaptic-like vesicles. The physiological significance of the synaptic and non-synaptic relationships between somatostatinergic neurons is discussed in terms of possible synchronization between homologous neurons of the somatostatin neuroendocrine system and control of these neurons by a central ultra-short loop feedback mechanism.  相似文献   
100.
The ability to coordinate the two hands effectively is a fundamental requirement for many everyday tasks. To investigate how bimanual coordination is achieved we asked subjects to perform discrete bimanual key-press responses under conditions in which the motoric (i.e., muscles employed) and external spatial (i.e., direction of movement in external space) relationships between the actions of the left and right index fingers were systematically varied. Subjects made simultaneous right and left index finger key-presses in response to an auditory tone. The right finger always made downward flexion movements whilst the left finger either flexed in a downward/upward direction, or extended in a downward/upward direction. Unimanual control trials of each movement type for both hands were also performed. Reaction times for each hand (RTs) and the inter-response interval (IRI) were recorded . Right hand RTs were significantly affected only when the left finger performed motorically different actions, but were unaffected by the external spatial direction in which the left hands actions were made. The IRI results followed a similar pattern with the worst coordination (highest IRI) occurring when the left finger performed different motor actions to the right finger regardless of the direction of the left hand movement. In contrast to other recent results from experiments examining oscillatory tasks (e.g., Mechsner et al. 2001), our results suggest that in discrete tasks there is a dominance of the motor relationship between the hands over the external spatial relationship.  相似文献   
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