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71.

Objective

To evaluate the frequency of inadvertent penetration of the digital flexor tendon sheath (DFTS) and/or distal interphalangeal joint (DIPJ) when using a direct endoscopic approach to the navicular bursa, and to evaluate an alternate direct approach to the navicular bursa.

Study Design

Cadaveric study.

Sample Population

Equine cadaver limbs (n = 40 for direct; n = 12 for alternate approach).

Methods

Four surgeons performed the direct endoscopic approach to the navicular bursa on 10 limbs each. Frequencies of inadvertent synovial penetration and iatrogenic damage were compared between surgeons. Use of an alternate direct approach, adopting a straight parasagittal trajectory, was evaluated by 2 surgeons.

Results

Inadvertent synovial penetration occurred in 45% of limbs (DFTS 37.5%; DIPJ 17.5%; and both structures 10%). Successful bursa entry was achieved on the first attempt in 45% of limbs. Significant variation in frequency of inadvertent synovial penetration was observed between surgeons (range 10–80%). Inadvertent synovial penetration did not occur when using the alternate direct technique. Iatrogenic damage to navicular bone fibrocartilage and/or deep digital flexor tendon occurred in 55% of limbs using the direct endoscopic approach and in 0% of limbs using the alternate direct approach.

Conclusion

Because of the considerable risk of inadvertent penetration of the DFTS and/or the DIPJ when making a direct endoscopic approach to the navicular bursa, it is advisable to investigate for inadvertent penetration when treating navicular bursa sepsis using a direct approach. The alternate direct technique may reduce the risk of inadvertent penetration; however, the view within the bursa may be restricted.  相似文献   
72.
Group A rotaviruses can infect both humans and animals. Individual rotavirus strains can occasionally cross species barriers and might hereby contribute to the emergence of new genotypes in heterologous hosts. The incidence and impact of zoonotic rotavirus are not well defined, and one reason for this is a lack of data about strains circulating in suspected reservoir animal hosts. In this study we report the incidence, genetic diversity, and molecular epidemiology of rotaviruses detected in domestic cattle and swine in 6 European countries. From 2003 to 2007, 1101 and more than 2000 faecal specimens were collected from swine and cattle, both healthy and diarrhoeic, and tested for rotaviruses. Viruses from positive stools were genotyped and a subset of strains was characterized by nucleotide sequencing and phylogenetic analysis of the VP7 (G) and VP4 (P) genes. Rotaviruses were detected in 43% of bovine samples and in 14% of porcine samples. In cattle, 10 different combinations of G and P types were identified and the most common strains were G6P[11] and G6P[5]. In swine, the number of identified G-P combinations was higher (n=21), however, no single combination was predominant across Europe. Newly described genotype specificities, P[27] and P[32], were identified in swine. When compared at the nucleotide sequence level, the identified porcine rotavirus strains and contemporary human strains grouped together phylogenetically, whereas bovine rotavirus strains formed separate clades. These data demonstrate large genetic diversity of porcine and bovine rotavirus strains across Europe, and suggest that livestock herds may serve as potential reservoirs for human infections.  相似文献   
73.
The inhibitory effect of seven different metals on the specific anammox activity of granular biomass, collected from a single stage partial nitritation/anammox reactor, was evaluated. The concentration of each metal that led to a 50% inhibition concentration (IC50) was 19.3 mg Cu+2/L, 26.9 mg Cr+2/L, 45.6 mg Pb+2/L, 59.1 mg Zn+2/L, 69.2 mg Ni+2/L, 174.6 mg Cd+2/L, and 175.8 mg Mn+2/L. In experiments performed with granules mechanically disintegrated (flocculent-like sludge), the IC50 for Cd+2 corresponded to a concentration of 93.1 mg Cd+2/L. These results indicate that the granular structure might act as a physical barrier to protect anammox bacteria from toxics. Furthermore, the presence of an external layer of ammonia oxidizing bacteria seems to mitigate the inhibitory effect of the metals, as the values of IC50 obtained in this study for anammox activity were higher than those previously reported for anammox granules. Additionally, the results obtained confirmed that copper is one of the most inhibitory metals for anammox activity and revealed that chromium, scarcely studied yet, has a similar potential inhibitory effect.  相似文献   
74.
Endosulfan is a potentially harmful, degradation resistant pesticide that is found in soils where it has been used. Despite being hydrophobic and having high affinity for soil matrix components, it has also been found in groundwater. To investigate this behavior, we studied the passage of a commercial emulsified formulation through a column of aggregated vineyard soil under simulated light rain. Breakthrough data were obtained using gas chromatography with electron capture detection to determine the concentration of endosulfan in samples extracted from the column periodically at several depths. These data, and analogous data obtained previously for the passage of bromide, were analyzed using the program CXTFIT v.2. Analysis of the bromide data strongly suggested the existence of preferential flow paths in the column. The endosulfan data were adequately accounted for by a model in which the preferential flow and nonpreferential flow regions are almost isolated from each other. These regions differ also as regards both the partition of endosulfan between soil and soil solution and the rate at which reversibly adsorbed endosulfan is transformed into irreversibly adsorbed endosulfan. The "irreversibility" sink term accounts also for biological and chemical degradation of endosulfan. The findings imply that soil humidity favors the transport of commercial endosulfan by the formation and maintenance of preferential flow paths in soil, controlling both the presence of endosulfan in groundwater and its high persistence in soil.  相似文献   
75.
The calorigenic effect of feeding (apparent heat increment, AHI) and post-prandial nitrogen excretion (PPNE) were measured in postlarval (PL 25–30) Penaeus setiferus, P. schmitti, P. duorarum and P. notialis fed a fixed ration of 3 mg/animal using purified diets with 40, 50, 60, or 65% protein. Both AHI and PPNE increased with increasing dietary protein. The contribution of PPNE to AHI varied from 6.1 to 94%, with lesser values for P. setiferus and greater ones for P. duorarum . Also, the AHI coefficient (percentage of ingested energy) increased with increasing dietary protein. The AHI and PPNE coefficients for the four shrimp species ranged from 0.3 to 6.5% and 0.02 to 5.04% of ingested energy, respectively. These results suggest close relationships among protein requirements, the capacity to use dietary proteins as a source of energy, and adaptation by different species to different types of food. The amount of energy used for production of ammonia is proposed as an adequate measure of the part played by dietary proteins in food cost.  相似文献   
76.
Influence of clarification, filtration, and storage on the concentration of rare earth elements (REEs) was studied in white wines by inductively coupled plasma mass spectrometry (ICP-MS). Smooth and parallel chondrite-normalized (CN) plots were obtained for wines which have never been in contact with fining agents. Clarification and filtration generally used in white wine production were simulated in the laboratory using nontreated reference wines, and CN plots were compared before and after treatments. Clarification by bentonites yields an overall increase in REE concentrations resulting in substantially parallel CN curves well above the plots of the corresponding nontreated wines. Filtration using silicate (SiO2), on the other hand, changes the CN profile in a nonparallel manner due to a higher release of La, Ce, Pr, Nd, and Gd, more than other elements studied. Filtration with cellulose powder causes a small increase in the concentration of light REEs, while the concentrations of other elements remain basically unchanged. Storage conditions could also affect the REE pattern of wine. We found that the influence of glass is greater than that of stainless steel and wood. In addition, we report that commercially available finished white wines from the same region show highly different REE patterns depending on the winemaking practices employed.  相似文献   
77.
In the Mesopotamia region (Argentina), rice is cropped on a wide range of soil types, and the response of rice to fertilizer application has been inconsistent even in soils with very low levels of available phosphorus. Phosphorus transformations in flooded soils depend on soil characteristics that may affect phosphorus availability. This study was conducted to determine which soil characteristics were related to the changes in P fractions during soil flooding. Soils were chosen from ten sites within the Mesopotamia region that are included in five different soil orders: Oxisols, Ultisols, Alfisols, Mollisols, and Vertisols. Soil phosphorus (P) was fractionated by a modified Hedley method before and after a 45 d anaerobic‐incubation period. Changes in the inorganic P extracted with resin depended on soil pH and were related to the exchangeable‐Fe concentration of soils (extracted with EDTA). Inorganic P extracted with alkaline extractants (NaHCO3 and NaOH) increased due to soil flooding. This increase was related to the organic‐C (OC) percentage of soils (r2 = 0.62, p < 0.01), and ranged from 13 to 55 mg kg–1. Even though previous studies showed that P associated with poorly crystalline Fe played an important role in the P nutrition of flooded rice, in this study, there was no relationship between ammonium oxalate–extractable Fe and P changes in soils due to flooding. Our results suggest that in the Mesopotamia region, changes in P fractions due to soil flooding are related to soil OC, soil pH, and soluble and weakly adsorbed Fe.  相似文献   
78.
This work presents the embryonic, larval, and postlarval development of Lithopoma undosa (L. undosa) (20 ± 2 C and the effect of natural inducers on the larval metamorphosis. Embryonic development until hatching of the trochophore larva took 15 h. Early veliger larvae with well‐developed shell were after 24 h. At 48 h, the operculum was completely formed. Cephalic tentacles were visible after 72 h. Larvae reached competence 6 to 7 d after fertilization, and was characterized by the presence of branched cephalic tentacles. The effect of natural inducers was evaluated. The percentage of metamorphosis with diatoms and adult mucus was 94% and 58% respectively, differing from the 25% without inducer. When was repeated, the metamorphosis was 100%, and 16% with benthic diatoms. The initial mean size of the postlarvae was 0.316 ± 0.02 mm. After 264 d the juveniles had attained a mean size of 5.98 ± 0.16 mm. These results will not only be of use in the evaluation of the culture of L. undosa, but also in studies on the characterization of inducers.  相似文献   
79.
We evaluated the performance of whiteleg shrimp Penaeus vannamei (Boone, 1931) in response to different stocking densities and acclimation periods. Shrimp postlarvae were acclimated from seawater (30 g L?1) to low‐salinity well water (<1.0 g L?1) at a constant hourly reduction rate of 40, 60, 80 and 100 h. After acclimation to low‐salinity well water, postlarvae from each acclimation time treatment were stocked in three replicate tanks at densities of 50, 100, 150 or 200 shrimps m?2 for 12 weeks of growth. Salinity averaged <1.0 g L?1 for each growth study. The different treatments resulted in significant differences in both the final body weight and the survival rate (SR). Shrimp acclimated for 100 h showed substantially improved survival (83%) relative to shrimp acclimated for shorter periods. Shrimp yields for all cultured periods ranged from 0.32 kg m?2 in tanks stocked at 50 m?2 to 1.14 kg m?2 in tanks stocked at 200 m?2. We conclude that whiteleg shrimp can be successfully grown in low‐salinity well water, and that the growth, production output and SRs are significantly higher when shrimp are acclimated for longer periods.  相似文献   
80.
Shrimp culture is a well‐established and fast‐growing industry that produces economic and social benefits in many countries. However, during the last years, it was severely affected by the emergence of the Early Mortality Syndrome (EMS) or Acute Hepatopancreatic Necrosis Disease (AHPND). This disease is mainly attributed to Vibrio parahaemolyticus, and currently, there is no effective cure or treatment. In this study, the use of T2A2 and VH5e bacteriophages was evaluated to control different AHPND‐positive strains (presumptively identified as V. parahaemolyticus, VPAHPND) under laboratory conditions. Lytic effect of T2A2 and VH5e bacteriophages against different strains isolated from AHPND outbreaks was corroborated. In addition, the effectiveness of the mixture of both phages was tested on a brine shrimp experimental infection model using three highly virulent VPAHPND strains. It has been found that phage‐treated brine shrimp had significantly higher survival percentage compared with non‐treated groups (p < .001). Also, phage cocktail was found to be harmless to the organisms. These results suggest that the phage mixture is worth considering as a possible control measure for positive AHPND strains, although it is clear that further and more extensive testing is needed.  相似文献   
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