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911.

Background

Identifying the aetiological agent of atypical pneumonia in human can sometimes be a tedious process, especially in cases where Mycoplasma pneumoniae, Legionella species and Chlamydia pneumoniae are ruled out. In such cases, a correct anamnesis of the patient is basic to clarify which pathogens might have produced the infection. For this reason, health professionals including veterinarians and laboratory personnel working with zoonotic pathogens should keep their doctors informed.

Case presentation

A human case of atypical pneumonia linked to Chlamydia abortus is reported. A 47-year-old male, a veterinarian researcher into chlamydiae, developed respiratory symptoms, breathing problems and high fever. Serological analyses ruled out the involvement of several respiratory pathogens, such as M. pneumoniae, Legionella pneumophila, Rickettsia conorii and C. pneumoniae, and Chlamydia abortus was identified as the possible aetiological agent of the infection. The isolation of C. abortus from the patient’s sputum and subsequent molecular analysis confirmed the presence of this microorganism.

Conclusion

As far as we know, although C. abortus has not been previously described as capable of causing pneumonia in humans, this is the first reported case of atypical pneumonia in which C. abortus is thought to have played an aetiological role.
  相似文献   
912.
Land abandonment is a global phenomenon whose environmental consequences are difficult to assess. The Murcia region is one of the most arid regions in southern Europe and also one of the most prone to land abandonment. This study researches which environmental features are more relevant to explain abandonment at the agricultural plot scale. Geomorphometric features were measured at different scales to investigate which scales could be more relevant. Two different models have been used: logistic regression, a statistical model that allows the interpretation of the involved features, and Random Forest, a machine learning model with a higher predictive power but lower interpretability. The combined use of both such models allows a set of predictors to be selected, which, when used with Random Forest, produce a map that is highly accurate for predicting abandonment and, when used with logistic regression, produce an interpretable model. The main conclusion is that climate is the most relevant factor to explain land abandonment. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
913.
In recent years plastination has begun to revolutionize the way in which human and veterinary gross anatomy can be presented to students. The study reported here assessed the efficacy of plastinated organs as teaching resources in an innovative anatomy teaching/learning system. The main objective was to evaluate whether the use of plastinated organs improves the quality of teaching and learning of anatomy. For this purpose, we used an interdepartmental approach involving the departments of Veterinary Anatomy, Human Anatomy, Veterinary Surgery, and Education Development and Research Methods. The knowledge base of control and experimental student groups was examined before and after use of the fixed or plastinated resources, respectively, to gather information evaluating the effectiveness of these teaching resources. Significant differences (p < 0.001) between control and experimental groups of Human and Veterinary Anatomy were observed in the post-test results. The Veterinary Surgery students had the most positive opinion of the use of plastinated specimens. Using these data, we were able to quantitatively characterize the use of plastinated specimens as anatomy teaching resources. This analysis showed that all the plastinated resources available were heavily used and deemed useful by students. Although the properties of plastinated specimens accommodate student needs at various levels, traditional material should be used in conjunction with plastinated resources.  相似文献   
914.
Pistachio cultivation requires the use of rootstock because grafting is the only form of vegetative propagation. The main commercial rootstocks are Pistacia integerrima L., Pistacia atlantica Desf., Pistacia terebinthus L. and Pistacia vera L. Pistachio is considered to be a drought and saline-resistant crop; however, there is little information describing varietal responses of rootstocks to water stress. Some studies have suggested that P. terebinthus L. is the most drought and cold resistant rootstock. The effect of the rootstock on the water relations of the grafted plant is crucial for improving crop performance under water stress conditions and for developing the best irrigation strategy. This work studied the physiological response to water stress of pistachio plants (P. vera L. cv. Kerman) grafted onto three different rootstocks P. terebinthus L., P. atlantica Desf. and a hybrid from crossbreeding P. atlantica Desf. × P. vera L. Plant physiological responses were evaluated during a cycle of drought and subsequent recovery in potted plants. Parameters measured were soil moisture, trunk diameter, leaf area, leaf number, leaf and stem dry weight, stem water potential, leaf stomatal conductance. The results showed different responses of cv. Kerman depending on the rootstock onto which it had been grafted. The hybrid rootstock was associated with a higher degree of stomatal control and reduced leaf senescence compared to P. atlantica and P. terebinthus, despite being associated with the most vigorous shoot growth. P. terebinthus enabled very effective stomatal control but was also associated with the most rapid leaf senescence. P. atlantica was associated with less vigorous shoot growth and similar levels of water stress as occurred with the others rootstocks under conditions of high evaporative demand, which was associated with lower stomatal control. The selection of the most effective rootstock choice for different environmental conditions is discussed.  相似文献   
915.
916.
A comparative quantitative analysis of the active triterpenoids in Centella asiatica samples collected in different locations in Madagascar was carried out to evaluate the natural variability in triterpenoid content and to select elite samples for further ex situ germplasm conservation and clonal propagation. The highest asiaticoside content (6.42%) was measured in samples collected in Mangoro region. In vitro propagation of C. asiatica was successfully achieved in hormone-free medium. Although lower asiaticoside content was detected in 8-week-old vitro plants, the Mangoro sample still showed the highest content in this triterpenoid constituent (1.78%). Acetoxycentellynol, a C(15)-polyacetylene, was found to be accumulated up to 18 times more in in vitro plants as compared to plant material collected in situ.  相似文献   
917.
An in vitro test was used to evaluate populations of one commercial cultivar and two land races of asparagus for resistance to Fusarium moniliforme. Seedlings of sixty-nine half-sib families (HSF) from each land race and 60 HSF from the cultivar were inoculated with a 0.5 ml suspension of 107 conidia/ml and visually scored 30 days later for percentage of affected root tissue. Genetic parameters were estimated and expected gains were calculated according to two selection methods, individual in both sexes and combined within and between HSF. Significant genetic variation was detected in the three populations; however, a greater progress in breeding is expected from the land races populations because the estimations of the additive variance were rather similar (221.86 ± 111.55 and 325.56 ± 128.27) and higher than for the cultivar (86.72 ± 78.38). This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
918.
This study aimed at assessing the dissolution rates of hydrated lime, Ca(OH)2 in fresh, oligohaline, mesohaline and euhaline waters and discussing its significance for liming of shrimp culture ponds. Appropriate volumes of seawater and distilled water were mixed to prepare oligohaline (1–4 g/L) and mesohaline waters (4–15 g/L). One gram of analytical grade calcium carbonate, CaCO3, or one gram of analytical grade calcium hydroxide, Ca(OH)2, were applied in 10‐L gallons filled with seawater (39.9 g/L), 10.7 g/L, 4.2 g/L and distilled water (0.0 g/L). The final TA of water was significantly higher for Ca(OH)2 than for CaCO3 only at salinities 4.2 and 10.7 g/L. It was concluded that hydrated lime, Ca(OH)2 is a better liming option than agricultural limestone, CaCO3 for moderately saline, hard and/or buffered waters (?4.5 ≤ Langelier saturation index, LSI ≤ ?0.7). In poorly saline, hard and/or buffered waters (LSI < ?4.5), limestone and lime would increase water TA similarly. Neither limestone nor lime should be applied on highly saline, hard and/or buffered waters (LSI > ?0.7) because a TA decrease is expected.  相似文献   
919.
Recirculating aquaculture systems (RASs) are an efficient method for developing sustainable aquaculture and the development of a feed strategy for RASs could be a key factor for the success of culturing Oreochromis niloticus. The daily protein intake (DPI) mathematical function related to body weight (BW) was designed (DPI = ?3.818 ln (BW) + 30.158) named DPI 1.0 = 100%. Three feeding rates were established, DPI 1.4, 1.2 and 1.0, and were implemented in an RAS production cycle (100 fish/m3) for 34 weeks. The final growth measurements were 908.0 ± 57.9 g (DPI 1.4), 887.0 ± 113.5 g (DPI 1.2) and 702.2 ± 38.1 g (DPI 1.0) (p < .05), with feed conversion rates (FCRs) of 2.3, 1.9 and 1.9, respectively; the survival was ≥ 98.3% (p > .05) for all treatments. DPI levels conditioned the growth of the fish and the proportion of lipid: protein in the bodies of O. niloticus but not in the fillets. The mathematical function DPI 1.2 = 120% (DPI = ?4.582 ln (BW) + 36.19) used in the RAS at the 40% protein level improved fish growth, the protein efficiency ratio and FCRs. The DPI values were estimated for 49 different cases and feeding strategies showed lower values than most of the different DPI mathematical functions used and cited in this work. Therefore, DPI metric is a good tool that provides the specific requirements of protein for O. niloticus growth, which can enable farmers to ration feed and improve energy use (kWh / fish) and facilitate the integration of RAS with horticulture.  相似文献   
920.
Mango (Mangifera indica L.) is one of the most important fruit crops in tropical and subtropical regions worldwide. On the coast of Granada and Malaga (SE Spain), irrigated subtropical fruit species have been introduced and cultivated on terraces with a considerable economic importance as the only European production region. The subtropical fruit production in this zone is possible with intensive irrigation on terraces, which are economically more profitable than traditional rainfed crops (almond and olive), which have been replaced or abandoned. A 2-year monitoring period was conducted using drainage lysimeters to determine the crop coefficients (Kc) and fruit yield in mango (Mangifera indica L. cv. Osteen) orchards. Also, some quality parameters such as titratable acidity, total soluble solids, and vitamin C were evaluated under these conditions. The averaged Kc values of mango trees varied within production cycle of 0.43, 0.67, and 0.63 at flowering, fruit set, and fruit growth, respectively. In this study, the fruit yield under full water requirements (100% ETC) averaged 24.1 kg tree?1, amounting to 21.2 kg ha?1 mm?1 in terms of water-use efficiency. The quality parameters of the mango fruits harvested in the study area were satisfactory. Thus, this study highlights the need to optimize the irrigation-water use according to actual mango requirements, thereby achieving more sustainable Mediterranean subtropical farming in orchard terraces.  相似文献   
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