The diagnosis of Neospora abortions in cattle     

Reichel MP  Drake JM 《New Zealand veterinary journal》1996,44(4):151-154

An indirect immunofluorescent antibody test (IFAT) and an enzyme-linked immunosorbent assay (ELISA) for specific anti-Neospora antibodies in bovine sera and foetal fluids were compared with histological examination results on aborted foetal material. The agreement between serological and histological examination results was poor, while the two serological tests showed a high degree of agreement. Serological testing of diagnostic serum samples and foetal fluids suggests that the prevalence of anti-Neospora antibodies in cattle which recently aborted is around 40%, in line with previous estimates of the number of abortions in dairy cattle caused by Neospora sp. A sero-epidemiological approach to the diagnosis of Neospora abortions in cattle may be suggested from these data.  相似文献   

Emergence of a New Cucurbit-Infecting Begomovirus Species Capable of Forming Viable Reassortants with Related Viruses in the Squash leaf curl virus Cluster     

Brown JK  Idris AM  Alteri C  Stenger DC 《Phytopathology》2002,92(7):734-742

ABSTRACT Cucurbit leaf curl virus (CuLCV), a whitefly-transmitted geminivirus previously partially characterized from the southwestern United States and northern Mexico, was identified as a distinct bipartite begomovirus species. This virus has near sequence identity with the previously partially characterized Cucurbit leaf crumple virus from California. Experimental and natural host range studies indicated that CuLCV has a relatively broad host range within the family Cucurbitaceae and also infects bean and tobacco. The genome of an Arizona isolate, designated CuLCV-AZ, was cloned and completely sequenced. Cloned CuLCV-AZ DNA A and B components were infectious by biolistic inoculation to pumpkin and progeny virus was transmissible by the whitefly vector, Bemisia tabaci, thereby completing Koch's postulates. CuLCV-AZ DNA A shared highest nucleotide sequence identity with Squash leaf curl virus-R (SLCV-R), SLCV-E, and Bean calico mosaic virus (BCaMV) at 84, 83, and 80%, respectively. The CuLCV DNA B component shared highest nucleotide sequence identity with BCaMV, SLCV-R, and SLCV-E at 71, 70, and 68%, respectively. The cis-acting begomovirus replication specificity element, GGTGTCCTGGTG, in the CuLCV-AZ origin of replication is identical to that of SLCV-R, SLCV-E, and BCaMV, suggesting that reassortants among components of CuLCV-AZ and these begomoviruses may be possible. Reassortment experiments in pumpkin demonstrated that both reassortants of CuLCV-AZ and SLCV-E A and B components were viable. However, for CuLCV-AZ and SLCV-R, only one reassortant (SLCV-R DNA A/CuLCV-AZ DNA B) was viable on pumpkin, even though the cognate component pairs of both viruses infect pumpkin. These results demonstrate that reassortment among sympatric begomovirus species infecting cucurbits are possible, and that, if generated in nature, could result in begomoviruses bearing distinct biological properties.  相似文献   

HIGH-RESOLUTION PARATHYROID SONOGRAPHY     

Erik R.  Wisner  D V M  Dominique  Penninck  DVM  David S.  Biller  DVM  Edward C.  Feldman  DVM  Christiana  Drake  PhD  Thomas G.  Nyland  DVM 《Veterinary radiology & ultrasound》1997,38(6):462-466

The purpose of this study was to assess the diagnostic utility of parathyroid ultrasonography to differentiate causes of hypercalcemia in dogs. We analyzed qualitative and quantitative ultrasound imaging findings and clinical pathology data from 33 dogs that underwent parathyroid ultrasound examination as part of the diagnostic evaluation for hypercalcemia. Diagnoses of the diseases causing hypercalcemia included parathyroid carcinoma (n = S), parathyroid adenoma (n = 15), parathyroid adenomatous hyperplasia (n = 6), chronic renal insufficiency (n = 3), and hypercalcemia of malignancy (n = 4). All parathyroid lesions were round or oval and hypoechoic compared with surrounding thyroid parenchyma. Adenomatous and adenocarcinomatous glands were 4 mm or larger in longest linear measurement on US examination and were statistically significantly larger than hyperplastic glands. (p < 0.001) Linear measurements of parathyroid glands acquired at the time of ultrasound examination correlated well with direct siz determination after surgical excision. (r²= 0.9, p < 0.0001) Parathyroid lesions <4 mm are highly suspicious for parathyroid adenoma or carcinoma, while US lesions <4 mm most likely represent primary adenomatous hyperplasia or secondary parathyroid hyperplasia. Parathyroid size estimation from ultrasound examination is an accurate predictor of true size.  相似文献   

Does Biochar Improve Establishment of Tree Seedlings in Saline Sodic Soils?     

Jessica A. Drake  Timothy R. Cavagnaro  Shaun C. Cunningham  W. Roy Jackson  Antonio F. Patti 《Land Degradation \u0026amp; Development》2016,27(1):52-59

Reforestation of saline sodic soil is increasingly undertaken as a means of reclaiming otherwise unproductive agricultural land. Currently, restoration of degraded land is limited to species with high tolerances of salinity. Biochar application has the potential to improve physical, biological and chemical properties of these soils to allow establishment of a wider range of plants. In a glasshouse trial, we applied biochar made from Acacia pycnantha (5 Mg ha⁻¹) or no biochar to either a low (EC_e 4·75 dS m⁻¹, ESP 6·9), a moderate (EC_e 27·6 dS m⁻¹, ESP 29·3) or a high (EC_e 49·4 dS m⁻¹, ESP 45·1) saline sodic soil. The regional common reforestation species Eucalyptus viminalis and Acacia mearnsii were planted as tubestock in to the soils. Early establishment indicators, including growth, plant condition and nutrition, were assessed at the end of a simulated growing season, 108 days after biochar application. Application of biochar increased height, and decreased root : shoot and the concentration of Mn, N and S in plants of E. viminalis when grown in the highly saline sodic soil. Biochar application increased the concentration of B in leaves of E. viminalis and increased the concentration of P, K and S in leaves of A. mearnsii when grown in the low saline sodic soil. The results confirm that there is potential for biochar to assist in reforestation of saline sodic soils. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

Imaging crystals, polymers, and processes in water with the atomic force microscope   总被引：45，自引：0，他引：45  

B Drake  C B Prater  A L Weisenhorn  S A Gould  T R Albrecht  C F Quate  D S Cannell  H G Hansma  P K Hansma 《Science (New York, N.Y.)》1989,243(4898):1586-1589

The atomic force microscope (AFM) can be used to image the surface of both conductors and nonconductors even if they are covered with water or aqueous solutions. An AFM was used that combines microfabricated cantilevers with a previously described optical lever system to monitor deflection. Images of mica demonstrate that atomic resolution is possible on rigid materials, thus opening the possibility of atomic-scale corrosion experiments on nonconductors. Images of polyalanine, an amino acid polymer, show the potential of the AFM for revealing the structure of molecules important in biology and medicine. Finally, a series of ten images of the polymerization of fibrin, the basic component of blood clots, illustrate the potential of the AFM for revealing subtle details of biological processes as they occur in real time.  相似文献   

A message from Earth     

Sagan C  Sagan LS  Drake F 《Science (New York, N.Y.)》1972,175(4024):881-884

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Pulse structure of four pulsars     

Drake FD  Craft HD 《Science (New York, N.Y.)》1968,160(3829):758-760

The pulse structure of the four known pulsars is given. The pulse is about 38 milliseconds for the two pulsars of longest period, and within the pulsewidth three subpulses typically appear. The pulsar of next longest period typically radiates two pulses separated about 23 milliseconds in time. The one short-period pulsar emits single pulses of constant shape. The first subpulses of all pulsars have nearly the same shape. The shape of the first subpulse agrees well with the pulse shape expected from a radio-emitting sphere which is excited by a spherically expanding disturbance, and in which the radio emission, once excited, decays exponentially.  相似文献   

The accademia dei lincei     

Drake S 《Science (New York, N.Y.)》1966,151(3715):1194-1200

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CO2 elicits long-term decline in nitrogen fixation     

Hungate BA  Stiling PD  Dijkstra P  Johnson DW  Ketterer ME  Hymus GJ  Hinkle CR  Drake BG 《Science (New York, N.Y.)》2004,304(5675):1291

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First radioisotope (potassium-argon) age of marine neogene rionegro beds in northeastern patagonia, Argentina     

Zinsmeister WJ  Marshall LG  Drake RE  Curtis GH 《Science (New York, N.Y.)》1981,212(4493):440

An average age of 9.41 million years was obtained from radioisotope (potassium-argon) age determinations of three glass concentrates of a tuff from the upper part of the marine Rionegrense at Punta Cracker in Golfo Nuevo, Argentina. This age correlates with the Tortonian marine stage of Europe and the Chasicoan Land Mammal Age of South America.  相似文献