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51.
Thomason JD Radlinsky MG Rapoport G Howerth EW Acevedo KF Fallaw TL Calvert CA 《Journal of Feline Medicine and Surgery》2012,14(4):276-279
A 4-year-old Ragdoll cat presented for dyspnea secondary to chylous pleural effusion to the University of Georgia Veterinary Teaching Hospital. Physical examination, complete blood count, serum chemistries, urinalysis, thoracic radiographs, abdominal radiographs, and thoracic fluid cytology and culture failed to identify an etiology for the chylous effusion. The patient tested negative for feline leukemia virus, feline immunodeficiency virus and heartworm disease. Respiration phasic influences on early diastolic trans-mitral, trans-tricuspid and pulmonary vein blood flow velocities during Doppler echocardiography were consistent with constrictive pericarditis. The cat underwent subtotal pericardectomy. The patient recovered without complication and is overtly healthy without radiographic or echocardiographic abnormalities 6-months post-surgery. Constrictive pericarditis should be considered in cats with idiopathic pleural effusion, with or without ascites, in which standard echocardiographic assessment is not suggestive of structural heart disease. If constrictive pericarditis is present, the Doppler characteristics outlined here may allow for this diagnosis to be made. Pericardectomy may be highly rewarding, although the specific etiology of the constrictive pericarditis may remain unknown. 相似文献
52.
53.
Paus T Zijdenbos A Worsley K Collins DL Blumenthal J Giedd JN Rapoport JL Evans AC 《Science (New York, N.Y.)》1999,283(5409):1908-1911
Structural maturation of fiber tracts in the human brain, including an increase in the diameter and myelination of axons, may play a role in cognitive development during childhood and adolescence. A computational analysis of structural magnetic resonance images obtained in 111 children and adolescents revealed age-related increases in white matter density in fiber tracts constituting putative corticospinal and frontotemporal pathways. The maturation of the corticospinal tract was bilateral, whereas that of the frontotemporal pathway was found predominantly in the left (speech-dominant) hemisphere. These findings provide evidence for a gradual maturation, during late childhood and adolescence, of fiber pathways presumably supporting motor and speech functions. 相似文献
54.
CM Volk JW Elkins DW Fahey RJ Salawitch GS Dutton JM Gilligan MH Proffitt M Loewenstein JR Podolske K Minschwaner JJ Margitan KR Chan 《Science (New York, N.Y.)》1996,272(5269):1763-1768
Airborne in situ observations of molecules with a wide range of lifetimes (methane, nitrous oxide, reactive nitrogen, ozone, chlorinated halocarbons, and halon-1211), used in a tropical tracer model, show that mid-latitude air is entrained into the tropical lower stratosphere within about 13.5 months; transport is faster in the reverse direction. Because exchange with the tropics is slower than global photochemical models generally assume, ozone at mid-latitudes appears to be more sensitive to elevated levels of industrial chlorine than is currently predicted. Nevertheless, about 45 percent of air in the tropical ascent region at 21 kilometers is of mid-latitude origin, implying that emissions from supersonic aircraft could reach the middle stratosphere. 相似文献
55.
In spite of the importance of the peduncle and pedicel in supporting and connecting flowers and fruits to the mother plant, these structures are little known in the olive, and more detailed information can be instrumental in studies of fruit development, ripening and abscission. The structure of pedicel and peduncle was studied at flowering and at fruit maturation for the Spanish olive cultivar “Picual”. Both organs have a stem-like structure. At flowering the pedicel is less developed as the transport requirements to individual flowers are minimal compared to that of the complete inflorescence, and the structure has high chances of being shed in the heavy flower abscission in this species. The peduncle is thicker, due to a ridged cortex, and has larger xylem vessel size. By fruit maturation in November, the overall diameter of both pedicel and peduncle increases, due to both conducting tissues and support tissues: in the pedicel the xylem increases 6-fold, in the peduncle 3-fold, while the phloem undergoes smaller increases. An important developmental feature of pedicel and peduncle is the increase in their capacity to mechanically support the growing fruit. To this end both organs, in addition to the increased thickness of the conducting tissues, produce a lignified sclerenchyma ring. Unlike the stem, however, which produces numerous sclereids, the sclerenchymatous ring only consists of fibres, which offer greater flexibility and make the structure less prone to breaking. 相似文献
56.
Ultrasonographic characteristics of soft tissue tumours in dogs 总被引:1,自引:1,他引:0
Objective To identify and describe the ultrasonographic features of soft tissue tumours in dogs.
Procedure Superficial soft tissue tumours of various histological types, including mast cell tumours (MCTs) and soft tissue sarcomas (STSs), were evaluated. Ultrasound was used to visualise internal characteristics of the tumour, including vascularity. Tumours were categorised according to size, shape, margin definition, tissue plane mobility, echogenicity, echotexture, acoustic shadowing or enhancement and vessel distribution. Objective measurements of intratumoural blood flow included velocities and maximal perfused cross-sectional area (fractional area). Logistic regression models incorporating a variety of data were used in an attempt to predict the histopathological type of tumours.
Results The logistic regression model defined by the parameters echotexture, margin definition and presence of subcapsular vessels was highly predictive of MCTs (> 73%; P = 0.024). Several other trends, including a larger size for STSs and less vascularity for both MCTs and STSs, were observed, but did not reach statistical significance.
Conclusion This preliminary study has shown the potential diagnostic value of ultrasound in differentiating soft tissue tumours. However, at present, ultrasound cannot replace biopsy and histopathological evaluation for tumour diagnosis. 相似文献
Procedure Superficial soft tissue tumours of various histological types, including mast cell tumours (MCTs) and soft tissue sarcomas (STSs), were evaluated. Ultrasound was used to visualise internal characteristics of the tumour, including vascularity. Tumours were categorised according to size, shape, margin definition, tissue plane mobility, echogenicity, echotexture, acoustic shadowing or enhancement and vessel distribution. Objective measurements of intratumoural blood flow included velocities and maximal perfused cross-sectional area (fractional area). Logistic regression models incorporating a variety of data were used in an attempt to predict the histopathological type of tumours.
Results The logistic regression model defined by the parameters echotexture, margin definition and presence of subcapsular vessels was highly predictive of MCTs (> 73%; P = 0.024). Several other trends, including a larger size for STSs and less vascularity for both MCTs and STSs, were observed, but did not reach statistical significance.
Conclusion This preliminary study has shown the potential diagnostic value of ultrasound in differentiating soft tissue tumours. However, at present, ultrasound cannot replace biopsy and histopathological evaluation for tumour diagnosis. 相似文献
57.
The study aims to compute the reference evapotranspiration (ETo) by six standard methods such as Penman Monteith, Modified Penman, Hargreaves, Radiation Balance, Blaney Criddle and Pan Evaporation by using the meteorological data of the All India Coordinated Research Project on Water Management at Rahuri, India (long. 74° 18′, lat. 19° 45′). These methods were compared with lysimeter crop evapotranspiration (ETc) by statistical tools. The results revealed that the total lysimeter ETc of red gram in 132 days' growing period (sowing to harvest) was 494?mm and the ETo in the above-mentioned models were 485.2, 486.9, 544.6, 547.6, 563.9 and 485.2?mm, respectively. Out of six models, ETo of Modified Penman and Pan Evaporation methods were very much close to lysimeter ETc, but the coefficient of variation was very high, i.e., 43.05% and 23.91%, respectively. But in the Hargreaves and Blaney Criddle methods, the coefficient of variation was low, i.e., 15.97% and 12.6%, respectively. Besides low coefficient of variation, these two methods require limited meteorological parameters such as minimum and maximum temperature, radiation. For generating these parameters even at regional level, minimum expenditure is involved. The crop coefficient (Kc) estimated by Hargreaves (Kc 0.90) and the Blaney Criddle (0.87) model for the entire growing season was very much close to the Food and Agricultural Organization (FAO) 56 model, and this can be used for estimating the irrigation requirement of red gram. 相似文献
58.
59.
A. Troncoso Juana Liñán M. Cantos M. M. Acebedo Hava F. Rapoport 《The Journal of Horticultural Science and Biotechnology》2013,88(5):584-587
SummaryThe feasibility and anatomical development of an in vitro olive cleft-graft method were studied. Grafting survival after 60.d in vitro was 85% which then dropped slightly to 67% after hardening. Three days after grafting, callus formation was observed along the cut surfaces of the rootstock and scion, after 6.d the first healing cellular unions were observed, and by 12.d after grafting a strong union developed. The first cellular differentiation to form vascular tissues was observed 12.d after grafting and continued rapidly until a total connection was reached 10.d later. Thus a complete graft union of the in vitro olive cleft-grafts was achieved in three weeks, and vigorous plants were established after 60.d of in vitro culture followed by 10.d of hardening. The in vitro olive cleft graft is suggested as an effective and useful method for germplasm multiplication. 相似文献
60.
GS Maciel RR Uscategui VT de Almeida MEF Oliveira MAR Feliciano WRR Vicente 《Reproduction in domestic animals》2014,49(4):701-704
The occurrence of the pyometra is most common in the first half of the dioestrus when there is decreased cellular immunity associated with increased serum concentration of progesterone in females. The aim of this study was to determine the immunological profile of bitches with pyometra, studying serum levels of IL‐2, IL‐4, IL‐10, IFN‐γ, KC‐like and TNF‐α and comparing them with those of healthy bitches in anoestrus, dioestrus and pregnant. Forty females were divided into four experimental groups: group 1 (G1): with pyometra (n = 10); group 2 (G2): bitches in the second week of gestation (n = 10); group 3 (G3): in anoestrus (n = 10); and group 4 (G4): in dioestrus (n = 10). The serum levels for IL‐2, KC‐like, INF‐γ and TNF‐α were similar for all experimental groups. The values obtained for IL‐10 were found increased (p < 0.001) in animals in dioestrus and pyometra compared with females in anoestrus and pregnant, and the levels of IL‐4 observed were significantly greater (p < 0.001) in bitches with pyometra when compared with others. The cytokine profile in animals with pyometra is similar to bitches in dioestrus for IL‐10 and had increase in IL‐4 for bitches with pyometra, which represents an anti‐inflammatory these cases. This suggests the presence of an immunosuppressive state in both cases, which may explain the propensity of bitches in dioestrus to be affected by pyometra and the severity of the disease on these animals. 相似文献