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Changes of cervical ultrasonographic physical parameters and their association with outcome of cerclage have not been fully elucidated. This study aimed at evaluating association between ultrasonographic physical cervical shapes before and after McDonald cerclage with the length of pregnancy. Cervical length, width and funneling rate were assessed by transvaginal ultrasonography before and after the procedure. Mean pre-cerclage cervical length, width and funneling rate were 29.28 +/- 5.54, 19.92 +/- 10.30 mm and 12.90 +/- 18.87%, respectively. The mean post-cerclage cervical length, diameter and funneling rate were 31.68 +/- 4.21, 9.78 +/- 13.86 and 4.32 +/- 10.89%, respectively (p < 0.001 for all pre- and post-cerclage changes). The mean post-cerclage duration of pregnancy was 19.78 +/- 5.94 weeks. There were significant direct correlations between the pre-and post-cerclage cervical lengths with pregnancy duration (r = 0.24, p = 0.04 and r = 0.44, p < 0.001, respectively). There were significant indirect correlations between the pre- and post-cerclage funneling rate with pregnancy duration (r = -0.30, p = 0.01 and r = -0.20, p = 0.01, respectively). Similar correlations were not significant for the cervical widths. This study showed that the pre- and post-cerclage ultrasonographically determined cervical length and funneling are good predictors of pregnancy duration.  相似文献   
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AIM: To evaluate the relationship between dietary diversity score (DDS) and cardiovascular risk factors in Tehranian adults. METHODS: In this population-based cross-sectional study, a representative sample of 581 subjects (295 males and 286 females) aged over 18 years, residents of Tehran, participated. Hypercholesterolaemia, hypertriglyceridaemia and low high-density lipoprotein cholesterol were defined according to the Adult Treatment Panel III guidelines of the National Cholesterol Education Program. Diabetes was defined as fasting plasma glucose concentration > or = 126 mg dl(-1) or 2-h post challenge glucose concentration > or = 200 mg dl(-1). Hypertension was defined on the basis of the sixth report of the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure. Dietary diversity was defined according to the Diet Quality Index revised. RESULTS: Mean (+/- standard deviation) DDS was 6.15 +/- 1.02. The probability of having diabetes (odds ratio (OR) among quartiles: 1.45, 1.26, 1.11 and 1.00, respectively; P for trend = 0.04) and hypertriglyceridaemia (OR = 1.41, 1.23, 1.05 and 1.00, respectively; P for trend=0.04) decreased with increasing quartile of the diversity score for whole grains. The probability of having obesity (OR among quartiles: 1.39, 1.06, 1.03 and 1.00, respectively; P for trend = 0.03), hypercholesterolaemia (OR = 1.46, 1.28, 1.11 and 1.00, respectively; P for trend = 0.03), hypertension (OR = 1.32, 1.17, 1.13 and 1.00, respectively; P for trend = 0.03) and high low-density lipoprotein cholesterol (LDL-C) (OR = 1.25, 1.12, 1.07 and 1.00, respectively; P for trend = 0.04) decreased with increasing quartile of the diversity score for vegetables. The probability of having hypercholesterolaemia, high LDL-C, hypertension and diabetes decreased with quartile of the DDS. But the probability of being obese increased with quartile of the DDS (P for trend = 0.03). CONCLUSION: DDS was inversely associated with cardiovascular risk factors in this cross-sectional study. Increased diversity scores of diets, to increase the variety score for vegetables, may be emphasised in programmes attempting to bring about changes in lifestyle.  相似文献   
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OBJECTIVE: To determine the nutritional behaviour of Tehranian adolescents. SUBJECTS AND METHODS: This study was undertaken on 7669 adolescents (4070 boys and 3599 girls) of 22 junior high schools and high schools as a representative sample of Tehranian adolescents. A validated knowledge, attitudes and practices (KAP) questionnaire and a food-frequency questionnaire (FFQ) were used. Factor analysis was used to determine the key questions. RESULTS: The mean ( +/- standard deviation) age and body mass index of the adolescents was 14 +/- 1 years and 27.2 +/- 11 kg m- 2. Although 82% of girls and 75% of boys had good nutritional knowledge, only 25% of boys and 15% of girls had good nutritional practice. Eighty-five per cent of adolescents knew that drinking too many soft beverages resulted in overweight or obesity, but only 4.5% of them did not drink soft beverages. Although 89% of adolescents knew that crisps and corn balls are not healthy snacks, 45% of them used such snacks during their break time. Thirty-seven per cent of adolescents preferred whole-grain biscuits to creamy wafer ones but only 10% of adolescents used whole-grain biscuits as a snack. The most frequently consumed snacks among Tehranian adolescents were sausage sandwiches, cocoa cola, crisps and corn balls, creamy wafers, cakes, chocolate and toffee. CONCLUSION: A low percentage of Tehranian adolescents have good nutritional behaviour and in most of them their nutritional practice does not accord with their nutritional knowledge. These results indicate the necessity of nutritional intervention in Tehranian adolescents.  相似文献   
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Knowledge and management of soil pH, particularly soil acidity across spatially variable soils is important, although this is greatly ignored by farmers. The objective of the study was to evaluate in-field spatial variability of soil pH, and compare the efficiency of managing soil pH through site-specific method vs. uniform lime application. The study was conducted on three sites with study sites I and II (23°50' S; 29°40' E), and study sites IIl (23°59' S; 28°52' E) adjacent to each other in the semi-arid regions of the Limpopo Province, South Africa. Soil samples were taken in four replicates from geo-referenced locations on a regular grid of 30 m. Soils were analyzed for pH, and SMP buffer pH. Soil maps were produced with Geographic Information System (GIS) software, and soil pH datasets were interpolated using a geostatistical tool of inverse distance weighing (IDW). Soil pH in the fields varied from 3.93 to 7.00. An excess amount of lime as high as 30 t/ha under uniform lime application were recorded. These recommendations were in excess on field areas that needed little or no lime applications. Again, there was an under applications of lime as much as 35 t/ha for uniform liming applications. This under- and over-recommendations of lime based on average soil pH values suggests that uniform soil acidity correction and soil pH management strategy is not an appropriate strategy to be adopted in these fields with spatially variable soils. The field can be divided into lime application zones of (1) high rates of lime, (2) low rates of lime and (3) areas that requires no lime at all so that lime rates are applied per zone. A key to site-specific soil acidity correction with lime is to reach ideal soil pH for the crop in all parts of the field.  相似文献   
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Avian influenza H9N2 viruses have become panzootic in Eurasia causing respiratory manifestations, great economic losses and occasionally being transmitted to humans. To evaluate the replication properties and compare the different virus quantification methods, four Eurasian H9N2 viruses from different geographical origins were propagated in embryonated chicken egg (ECE) and Madin-Darby canine kidney epithelial cell systems. The ECE-grown and cell culture-grown viruses were monitored for replication kinetics based on tissue culture infectious dose (TCID50), Hemagglutination (HA) test and quantitative real time RT-PCR (qRT-PCR). The cellular morphology was analyzed using immunofluorescence (IF) and cellular ELISA was used to screen the sensitivity of the viruses to amantadine. The Eurasian wild type-H9N2 virus produced lower titers compared to the three G1-H9N2 viruses at respective time points. Detectable titers were observed earliest at 16 h post inoculation (hpi), significant morphological changes on cells were first observed at 32 hpi. Few nucleotide and amino acid substitutions were noticed in the HA, NA and NS gene sequences but none of them are related to the known conserved region that can alter pathogenesis or virulence following a single passage in cell culture. All studied H9N2 viruses were sensitive to amantadine. The G1-H9N2 viruses have higher replication capabilities compared to the European wild bird-H9N2 probably due to their specific genetic constitutions which is prerequisite for a successful vaccine candidate. Both the ECE and MDCK cell system allowed efficient replication but the ECE system is considered as the better cultivation system for H9N2 viruses in order to get maximum amounts of virus within a short time period.  相似文献   
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