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131.
A. I. D. C. Marques J. Tattersall D. J. Shaw E. Welsh 《The Journal of small animal practice》2009,50(4):162-166
O bjectives : The objective of this study was to evaluate the relationship between the volume of fluid being produced at the time of thoracostomy drain removal and the time to hospital discharge in dogs and cats.
M ethods : Records of 101 dogs and 26 cats with thoracostomy drains were reviewed. Three subgroups were created according to the reason for thoracostomy drain placement: P (postsurgical), A (air) and F (fluid). A generalised linear model with Poisson Errors was performed to test the relationship between the volume of fluid produced at the time of thoracostomy drain removal and the time to discharge. The volume of fluid produced and the time to discharge were compared between species and subgroups.
R esults : No significant relationship was found between the volume of fluid produced at the time of thoracostomy drain removal and the time to discharge in either species or between the time to discharge and the reason for thoracostomy drain placement. Animals with a volume of fluid higher than 2 ml/kg/day at the time of thoracostomy drain removal did not have increased hospitalisation times.
C linical S ignificance : Thoracostomy drain can be removed, without clinical compromise, when the volume of fluid produced exceeds 2 ml/kg/day. However, other clinical parameters must be taken into consideration. 相似文献
M ethods : Records of 101 dogs and 26 cats with thoracostomy drains were reviewed. Three subgroups were created according to the reason for thoracostomy drain placement: P (postsurgical), A (air) and F (fluid). A generalised linear model with Poisson Errors was performed to test the relationship between the volume of fluid produced at the time of thoracostomy drain removal and the time to discharge. The volume of fluid produced and the time to discharge were compared between species and subgroups.
R esults : No significant relationship was found between the volume of fluid produced at the time of thoracostomy drain removal and the time to discharge in either species or between the time to discharge and the reason for thoracostomy drain placement. Animals with a volume of fluid higher than 2 ml/kg/day at the time of thoracostomy drain removal did not have increased hospitalisation times.
C linical S ignificance : Thoracostomy drain can be removed, without clinical compromise, when the volume of fluid produced exceeds 2 ml/kg/day. However, other clinical parameters must be taken into consideration. 相似文献
132.
J. R Butnor M. L. Pruyn D. C. Shaw M. E. Harmon A. N. Mucciardi M. G. Ryan 《Forest Pathology》2009,39(5):309-322
Our objective was to test ground penetrating radar (GPR) to non‐destructively estimate decay volumes in living coniferous trees. GPR is geophysical tool which uses an antenna to propagate short bursts of electromagnetic energy in solid materials and measure the two‐way travel time and amplitude of reflected signals. We compared estimates of bole decay from data collected with a SIR 3000 GPR system equipped with a 900 MHz antenna to measurements of decay from stem cross sections and increment cores for three conifer species (Pseudotsuga menziesii, Thuja plicata and Tsuga heterophylla). We found that near‐surface decay, air‐filled voids and desiccated boles had unique electromagnetic signatures, which could be separated from other defects. GPR successfully estimated the percent area of air‐filled cavities and was not significantly different than results from destructive sampling. However, separation of incipient to severe decay from benign reflectors (e.g. moisture gradient between sapwood and heartwood) in conifers was much less diagnostic than with angiosperms. A limited assessment of Acer saccharum showed that GPR has potential to detect defects in angiosperms; however, more research is needed to outline the full range of detectable defects. Based on the trees in this study, the potential for GPR to detect decay‐related defects in conifers seems limited. Despite problems detecting decay, reflections originating from the sapwood : heartwood boundary may prove useful to determine thickness of functional sapwood in conifers, but accurate quantification will require further technical development. 相似文献
133.
Strawberry ( Fragaria × ananassa ) seedlings from 50 bi-parental crosses among 20 elite genotypes were evaluated for resistance to Phytophthora cactorum after artificial inoculation. Plots of seedlings or runner plants were rated using a disease severity score and the percentage of stunted plants per plot. The distribution of cross means for percentages of plants with stunting was highly skewed; 79% of the inoculated seedlings showed some level of stunting compared to non-inoculated control seedlings, and all but one of the crosses had 50% or more stunted plants. Disease severity scores for the bi-parental crosses were normally distributed and expressed a range of variation not reflected by the percentage of visibly stunted plants. Factorial analysis based on seedling plot means demonstrated significant additive genetic variance for the disease severity score, and the additive genetic variance was 1·9 times greater than the estimated dominance variance. The cross-mean heritability was for the severity score. Estimates of the additive genetic variance component using the covariance of severity scores obtained from the seedling analysis and with severity scores for their parents evaluated in a commercial environment were similar, and 0·30, respectively. Most of the selection response obtained through genotypic selection would thus be transferred to segregating offspring. 相似文献
134.
The relative importance of conidia and ascospores as primary inoculum of Venturia inaequalis in a southeast England orchard
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Apple scab, caused by Venturia inaequalis, can lead to large losses of marketable fruit if left uncontrolled. The disease appears in orchards during spring as lesions on leaves. These primary lesions are caused by spores released at bud burst from overwintering sources; these spores can be sexually produced ascospores from the leaf litter or asexual conidia from mycelium in wood scab or within buds. The relative importance of conidia and ascospores as primary inoculum were investigated in an orchard in southeast England, UK. Potted trees not previously exposed to apple scab were placed next to (c. 1 m) orchard trees to trap air‐dispersed ascospores. Number and position of scab lesions were assessed on the leaves of shoots from both the potted trees (infection by airborne ascospores) and neighbouring orchard trees (infection by both ascospores and splash‐dispersed, overwintered conidia). The distribution and population similarity of scab lesions were compared in the two tree types by molecular analysis and through modelling of scab incidence and count data. Molecular analysis was inconclusive. Statistical modelling of results suggested that conidia may have contributed approximately 20–50% of the primary inoculum in early spring within this orchard: incidence was estimated to be reduced by 20% on potted trees, and lesion number by 50%. These results indicate that, although conidia are still a minority contributor to primary inoculum, their contribution in this orchard is sufficient to require current management to be reviewed. This might also be true of other orchards with a similar climate. 相似文献
135.
Organogenesis and foetal haemodynamics during the normal gestation of healthy black‐rumped agoutis (Dasyprocta prymnolopha,Wagler, 1831) bred in captivity
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FCA Sousa GT Pessoa LS Moura JR Araújo RPS Rodrigues MAPS Barbosa AN Diniz AB Souza EG Silva LU Lucena MP Sanches OF Silva‐Filho PC Guerra JM Sousa WC Neves FR Alves 《Reproduction in domestic animals》2017,52(1):60-66
The objective of this study was to define the patterns of organogenesis and foetal haemodynamics during the normal gestation of healthy agoutis (Dasyprocta prymnolopha) kept in captivity. Thirty pregnant agoutis that ranged in size from small to medium and weighed between 2.5 and 3 kg underwent B‐mode and Doppler ultrasonography for the biometric evaluation of the foetal organs. The foetal aortic blood flow proved to be predominantly systolic, and the measured flow velocity was 78.89 ± 2.95 cm/s, with a maximum pressure gradient of 2.12 ± 0.27 mmHg. The liver was characterized by its large volume, occupying the entire cranial aspect of the abdominal cavity, and it was associated cranially with the diaphragm and caudally with the stomach. The flow velocity in the portal vein was estimated to equal 12.17 ± 2.37 cm/s, with a resistivity index of 0.82 ± 0.05. The gallbladder was centrally located and protruded cranially towards the diaphragm. The spleen was visualized as an elongated structure with tapered cranial and caudal extremities, and the foetal kidneys were visualized bilaterally in the retroperitoneal region, with the right kidney positioned slightly more cranially than the left. The morphological characterization and hemodynamic analysis of the foetal organs of black‐rumped agoutis via B‐mode and Doppler ultrasonography allow determination of the vascular network and of reference values for the blood flow required for perfusing the anatomical elements essential for maintaining the viability of foetuses at different gestational ages. 相似文献
136.
Participation of phosphofructokinase,malate dehydrogenase and isocitrate dehydrogenase in capacitation and acrosome reaction of boar spermatozoa
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E Breininger D Dubois VE Pereyra PC Rodriguez MM Satorre PD Cetica 《Reproduction in domestic animals》2017,52(5):731-740
The aim of this work was to determine the enzymatic activity of phosphofructokinase (PFK), malate dehydrogenase (MDH) and isocitrate dehydrogenase (IDH) in boar spermatozoa and study their participation in bicarbonate‐induced capacitation and follicular fluid‐induced acrosome reaction. Enzymatic activity of these enzymes was determined spectrophotometrically in extracts of boar spermatozoa. Sperm suspensions were incubated in the presence of bicarbonate (40 mM), a well‐known capacitation inducer, or follicular fluid (30%), as an acrosome reaction inducer, and different concentrations of oxoglutarate, oxalomalate and hydroxymalonate, inhibitors of PFK, IDH and MDH, respectively. Capacitation percentages were determined by the fluorescence technique of chlortetracycline (CTC), and true acrosome reaction was determined by trypan blue and differential–interferential contrast, optical microscopy. The activity of PFK in boar spermatozoa enzymatic extracts was 1.70 ± 0.19 U/1010 spermatozoa, the activity of NAD‐ and NADP‐dependent IDH was 0.111 ± 0.005 U/1010 and 2.22 ± 0.14 U/1010 spermatozoa, respectively, and the activity of MDH was 4.24 ± 0.38 U/1010 spermatozoa. The addition of the specific inhibitors of these enzymes prevented sperm capacitation and decreased sperm motility during capacitation and inhibited the acrosome reaction (AR), without affecting the sperm motility during this process. Our results demonstrate the participation of PFK, IDH and MDH in bicarbonate‐induced capacitation and follicular fluid‐induced acrosome reaction in boar spermatozoa, contributing to elucidate the mechanisms that produce energy necessary for these processes in porcine spermatozoa. 相似文献
137.
Shaw DE Maragakis P Lindorff-Larsen K Piana S Dror RO Eastwood MP Bank JA Jumper JM Salmon JK Shan Y Wriggers W 《Science (New York, N.Y.)》2010,330(6002):341-346
Molecular dynamics (MD) simulations are widely used to study protein motions at an atomic level of detail, but they have been limited to time scales shorter than those of many biologically critical conformational changes. We examined two fundamental processes in protein dynamics--protein folding and conformational change within the folded state--by means of extremely long all-atom MD simulations conducted on a special-purpose machine. Equilibrium simulations of a WW protein domain captured multiple folding and unfolding events that consistently follow a well-defined folding pathway; separate simulations of the protein's constituent substructures shed light on possible determinants of this pathway. A 1-millisecond simulation of the folded protein BPTI reveals a small number of structurally distinct conformational states whose reversible interconversion is slower than local relaxations within those states by a factor of more than 1000. 相似文献
138.
CH Annandale PC Irons VP Bagla UI Osuagwuh EH Venter 《Reproduction in domestic animals》2010,45(2):250-255
The objectives of this work were to determine the site of persistence of lumpy skin disease virus (LSDV) in bulls shedding the virus in semen for a period longer than 28 days, to determine if the virus is present in all fractions of semen and to study lesions that developed in the genital tract. Six serologically negative postpubertal bulls were experimentally infected with a virulent field isolate of LSDV. The polymerase chain reaction (PCR) was performed on sheath washes, vesicular fluid, supernatant and cell‐rich fractions of semen from day 10 to day 26 postinfection (p.i.). Bulls that were positive by PCR on the whole semen sample collected on day 28 p.i. were slaughtered and tissue samples from their genital tracts submitted for histopathological evaluation, immunoperoxidase staining, virus isolation and PCR. Two of the bulls developed severe lumpy skin disease (LSD) and were found to be shedding viral DNA in their semen on day 28 p.i. Viral DNA was identified in all semen fractions from all bulls, but mostly from the cell‐rich fraction and from the severely affected bulls. The PCR assay was positive on postmortem samples of testes and epididymides from the two severely affected bulls. Virus could be recovered from the testes of these two bulls and from the epididymis of one of them. Immunoperoxidase staining was positive for LSDV staining in sections of testes and epididymides exhibiting necrosis. This study suggests that the testis and epididymis are sites of persistence of LSDV in bulls shedding virus in semen for prolonged periods and revealed that viral DNA is present in all fractions of the ejaculate. 相似文献
139.
Tree-ring analysis was applied to assess the impacts of the fungal disease Swiss needle cast on the radial growth of mature Douglas-fir (Pseudotsuga menziesii) forests in the western Oregon Coast Range. Although considered endemic to the Pacific Northwest, Swiss needle cast has significantly lowered productivity in Douglas-fir forests only in the past 20–30 years. To date, studies on Swiss needle cast impacts have almost exclusively involved young (<30 years) plantation trees. To better describe the history of Swiss needle cast and its impacts on older (>80 years) trees, we extracted tree cores from dominant and codominant Douglas-fir and western hemlock (Tsuga heterophylla) in three even-aged stands in western Oregon. In the least affected stand growth rates of both species did not significantly differ, while at the most severely diseased site Douglas-fir radial growth was reduced by as much as 85%. Growth reductions likely associated with Swiss needle cast were dated to as early as 1950, though the most severe impacts occurred after 1984. An index of Swiss needle cast severity significantly (p < 0.01) related to instrumental records of air temperatures such that warm conditions from March through August were associated with reduced radial growth at the most severely affected site. Overall, this study demonstrates that even mature forests of natural origin are susceptible to severe growth reductions by Swiss needle cast, that warmer spring and summer temperatures are associated with Swiss needle cast impacts, and that the disease appears to be increasing in severity. 相似文献
140.
Flour derived from Cycas micronesica seeds was once the dominant source of starch for Guam's residents. Cycad consumption has been linked to high incidence of human neurodegenerative diseases. We determined the distribution of the sterols stigmasterol and β-sitosterol and their derived glucosides stigmasterol β-d-glucoside and β-sitosterol β-d-glucoside among various plant parts because they have been identified in cycad flour and have been shown to elicit neurodegenerative outcomes. All four compounds were common in seeds, sporophylls, pollen, leaves, stems, and roots. Roots contained the greatest concentration of both free sterols, and photosynthetic leaflet tissue contained the greatest concentration of both steryl glucosides. Concentration within the three stem tissue categories was low compared to other organs. Reproductive sporophyll tissue contained free sterols similar to seeds, but greater concentration of steryl glucosides than seeds. One of the glucosides was absent from pollen. Concentration in young seeds was higher than old seeds as reported earlier, but concentration did not differ among age categories of leaf, sporophyll, or vascular tissue. The profile differences among the various tissues within these organs may help clarify the physiological role of these compounds. 相似文献