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91.
常言道:孕妇一人吃两人补。但相对于纯粹地增加食物摄入量,孕妈妈们更应该注意摄入合适的膳食,以保证为自己和胎儿提供最佳的营养。事实上,胎儿的发育全赖于通过妈妈的脐带输送必需的营养。因此,孕妇缺乏任何一种营养都可能导致腹中胎儿营养不良。  相似文献   
92.
Objective – To evaluate the tolerance of a continuous positive airway pressure (CPAP) mask in tranquilized dogs and compare PaO2 in arterial blood in dogs receiving oxygen with a regular face mask or CPAP mask set to maintain a pressure of 2.5 or 5 cm H2O. Design – Prospective, randomized clinical study. Setting – University teaching hospital. Animals – Sixteen client‐owned dogs without evidence of cardiopulmonary disease were studied. Interventions – Eight animals were randomly assigned to each of 2 treatment groups: group A received 2.5 cm H2O CPAP and group B received 5 cm H2O CPAP after first receiving oxygen (5 L/min) by a regular face mask. Animals were tranquilized with acepromazine 0.05 mg/kg, IV and morphine 0.2 mg/kg, IM. An arterial catheter was then placed to facilitate blood sampling for pHa, PaO2, and PaCO2 determinations before and after treatments. Direct mean arterial pressure, heart rate, respiratory rate, and temperature were also recorded after each treatment. Measurements and Main Results – CPAP administration was well tolerated by all animals. The mean arterial pressure, heart rate, respiratory rate, temperature, PaCO2, and pHa, did not differ at any time point between groups. Differences were seen in oxygenation; in group A, PaO2 significantly increased from a mean of 288.3±47.5 mm Hg with a standard mask to a mean of 390.3±65.5 mm Hg with the CPAP mask and in group B, PaO2 increased similarly from 325.0±70.5 to 425.2±63.4 mm Hg (P<0.05); no differences were detected between the 2 CPAP treatments. Conclusions – In healthy tranquilized dogs noninvasive CPAP is well tolerated and increases PaO2 above values obtained when using a regular face mask.  相似文献   
93.
Regions within the mitochondrial gene encoding for the nicotinamide dehydrogenase subunit 4 (nad4) were characterized to evaluate the extent of genetic variation within and among Xiphinema diversicaudatum and Xiphinema simile populations. Four different sequence variants of nad4 were determined among eight populations of X. diversicaudatum and three variants among three populations of X. simile. Nucleotide variation was detected in 28 of 411 bp (2.43 to 4.87 %) in X. diversicaudatum and in three of 395 bp (0.25 to 0.76 %) in X. simile. This represents the first study based on the characterization of the nad4 gene for the analysis of population genetic of two Xiphinema species.  相似文献   
94.
Summary

The effects of temperature, duration of temperature, growth stage, rate of cooling, daylength during raising, shading, seed quality, moisture stress and sowing date on blindness in calabrese cv. Marathon were investigated in eight experiments over three years. Of these only batches of plants raised throughout the winter produced appreciable levels of blindness. The incidence of the disorder varied from zero to 80% in plants which received no specific supplementary cold treatment. High levels of blindness were strongly associated with low solar radiation in the period just before plants went blind and were less well associated with low temperatures in the same period. However, it is not possible to separate effects of light and temperature in these data. There are suggestions that competition between leaves for limited assimilate may be responsible for switching off leaf production.  相似文献   
95.
This study was carried out to estimate the level of diversity existing within some common bean landraces still cultivated in Nebrodi mountains, North-western area of Sicily. The multidisciplinary approach adopted to reach this goal involved the characterisation of collected material through morphological, biochemical and molecular marker analyses. The nutritional quality of seeds was also investigated in view of the proposition of the best landraces as niche products. Results showed that those bean landraces retain a considerable level of heterogeneity. The use of both biochemical and molecular markers showed that all landraces clustered into two main groups, corresponding to the Andean and Mesoamerican gene pools. Our results suggest that the best strategy for preserving the diversity of common bean from a restricted area such as Nebrodi mountains, necessitates of a deep knowledge of germplasm to avoid the loss of precious genetic resources or, on the contrary, the safeguard of populations genetically redundant.  相似文献   
96.
97.
One hundred and eighty one cats living in central Italy were tested for the presence of Giardia and Cryptosporidium infection by IFAT test and specific PCRs. Overall eight (4.4%) samples were IFAT-positive for Giardia. All the IFAT-positive samples for Giardia scored positive for the PCRs, and three more samples IFAT-negative generated PCR products leading to a total 6.1% molecular positivity rate for Giardia. All the examined samples were negative for Cryptosporidium. Sequencing of samples molecularly positive to Giardia indicated that three cats harbored the zoonotic Giardia duodenalis Assemblage A, whereas all other positive animals were infected with the feline-specific G. duodenalis Assemblage F. Phylogenetic analysis carried out on the sequences obtained supported the clustering of the isolates within Assemblages A and F. The results here presented provide data on the occurrence of Giardia genotypes in cats living in close contact with humans highlighting the potential importance of this protozoan disease for the public health.  相似文献   
98.
The objective of this study was to compare the occurrence and the genotypes and species of Giardia duodenalis and Cryptosporidium spp. in beef and dairy cattle from farms in the Regional Municipality of Waterloo, Ontario, in an effort to determine the potential for zoonotic transmission from these animals. Pooled manure samples were collected from 45 dairy cattle farms and 30 beef cattle farms. The presence of Giardia cysts and Cryptosporidium oocysts was determined by immunofluorescence microscopy, while nested-PCR and DNA sequencing were used to determine genotypes and species. The overall farm prevalence was very high for both Giardia and Cryptosporidium, and was similar for dairy cattle farms (96 and 64%, respectively) and beef cattle farms (97 and 63%, respectively). However, on dairy cattle farms, G. duodenalis and Cryptosporidium spp. were detected in 44% and 6% of total pooled pen manure samples, respectively, with the occurrence of both parasites being generally higher in calves than in older animals. Most Giardia isolates were identified as either the host-adapted genotype G. duodenalis Assemblage E or the zoonotic Assemblage B. Cryptosporidium parvum and Cryptosporidium andersoni were the most frequently identified species in dairy cattle, while the non-zoonotic species Cryptosporidium ryanae and Cryptosporidium bovis were also found. On beef cattle farms, 72% and 27% of the total pooled pen manure samples were positive for Giardia and Cryptosporidium, respectively, with no obvious correlation with age. All Giardia isolates in beef cattle were identified as G. duodenalis Assemblage E, while all Cryptosporidium isolates were identified by sequence analysis as C. andersoni, although microscopic analyses, and subsequent restriction fragment length polymorphism analyses, indicated that other Cryptosporidium species were also present. The results of this study indicate that although Giardia and Cryptosporidium were identified in a higher overall percentage of the pooled beef cattle manure samples than in dairy cattle, firmly established zoonotic genotypes and species were much more common in dairy cattle than in beef cattle in this region. Dairy cattle, and especially dairy calves, may, therefore, pose a greater risk of infection to humans than beef cattle. However, these results may also provide evidence of potential zooanthroponotic transmission (human to animal).  相似文献   
99.

Purpose  

In this study, bioavailability and water extractability of Cd in a panel of 110 natural aged heavy metal-polluted soils from northern France containing up to 20.1 mg of Cd per kilogramme was evaluated.  相似文献   
100.
Atrazine is one of the most used herbicides worldwide; however, consequences of its long-term agricultural use are still unknown. A laboratory study was performed to examine changes in microbial properties following ethylamino-15N-atrazine addition, at recommended agronomic dose, to five acidic soils from Galicia (NW Spain) showing different physico-chemical characteristics, as well as atrazine application history. Net N mineralization was observed in all soils, with nitrate being the predominant substance formed. The highest values were detected in soils with low atrazine application history. From 2% to 23% of the atrazine-15N was found in the soil inorganic-N pool, the highest values being detected after 9 weeks in soils with longer atrazine application history and lower indigenous soil N mineralization. The application of atrazine slightly reduced the amount of soil N mineralized and microbial biomass at short term. Soluble carbohydrates and β-glucosidase and urease activity decreased with incubation time, but were not significantly affected by the single application of atrazine. Microbial community structure changed as consequence of both soil type and incubation time, but no changes in the phospholipid fatty acid (PLFA) pattern were detected due to recent atrazine addition at normal doses. The saturated 17- to 20-carbon fatty acids had higher relative abundance in soils with a longer atrazine history and fungal biomass, as indicated by the PLFA 18:2ω6,9, decreased with the incubation time. The results suggested that the PLFA pattern and soil N dynamics can detect the long-term impact of repeated atrazine application to agricultural soils.  相似文献   
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