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1.
A 4-month old, 200 kg, grey warmblood colt presented for a firm, non painful mass on the distal medial aspect of the left third metatarsus. Excisional biopsy revealed a diagnosis of haemangiosarcoma. Equine haemangiosarcoma is uncommon and only limited reports of successful treatment are available. The prognosis for survival is therefore considered to be poor. After two separate incidences of recurrence with incomplete excision of the tumour, intralesional treatment with cisplatin without excision or debulking was performed on three separate occasions. Intralesional cisplatin injection was performed at monthly intervals for three treatments. Four years post treatment with cisplatin, the horse remained in remission. This case report describes the diagnostic and treatment challenges for successful treatment of a primary haemangiosarcoma on the distal limb of a warmblood foal using intralesional cisplatin chemotherapy.  相似文献   
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本论文研究了饲料加工的两个关键参数(调质温度和时间)对育肥猪颗粒饲料淀粉糊化度和维生素沉积的影响。日粮配方为含30%干酒糟及其可溶物的玉米-豆粕型基础日粮。整个试验中配方保持不变。本试验采用2×3双因子设计,调质温度分别为77℃和88℃,调质时间分别15秒、30秒和60秒。此外,本试验还设置一个对照组,对照组饲料不采用调质制粒工艺,而是采用粉料饲喂。因此,本试验共有7个处理组。采集调质后制粒前(热干粉)、制粒后冷却前(热制粒)、以及制粒冷却后(冷制粒)的样品,并分析这三种样品的总淀粉率、淀粉糊化  相似文献   
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Many Mexican women are deficient in folic acid. Fortification of the corn tortilla could be an effective way to help increase the folic acid levels among the Mexican population. Previous studies have shown significant folic acid losses in the masa dough as it is held before baking. This loss in folic acid could be owing to utilization by lactic acid bacteria naturally present in the masa. The objective of this study was to determine the effect of bacteria native to corn masa on the folic acid content in masa. Bacteria in dough samples from six mills in Guadalajara, Mexico, were isolated and identified. Bacterial isolates were inoculated into sterile fortified corn masa flour, which was converted to masa and held at 56°C for 0, 3, and 6 h, replicating the conditions of freshly milled masa as held before baking. All samples, including the control, showed losses of folic acid between 66 and 79% w/w in the first 3 h of incubation. Because folic acid degradation in the sterile control sample was not different than the inoculated sample results, the decline in folic acid was not owing to bacteria (mainly Streptococcus spp.) present in the masa flour but appeared to be a chemical degradation related to time and temperature.  相似文献   
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Dunn GM  Connor DJ 《Tree physiology》1993,13(4):321-336
Diurnal measurements of sap velocity were made in 50-, 90-, 150- and 230-year-old mountain ash (Eucalyptus regnans F. Muell.) forests in the North Maroondah catchment (southeast Australia) over the periods January 8, 1990 to April 4, 1990 and October 29, 1990 to April 16, 1991. Over the two periods, daily mean sap velocities for the four forests, in order of increasing age, were 11.5, 11.4, 9.9 and 11.8 cm h(-1) respectively. Daily mean sap velocity did not differ significantly among the 50-, 90- and 230-year-old plots. However, in the 150-year-old trees it was significantly smaller by an average of 14%. Sap velocity varied diurnally and also between positions within individual trees and among trees both within and between stands. Despite this variability, the sampling intensity and duration were sufficient to establish that behavior was highly correlated among individuals within plots. There was a significant decline with age in the overstory sapwood conducting area of these forests. In order of increasing age, the values were 6.7, 6.1, 4.2 and 4.0 m(-2) ha(-1), respectively. When combined with daily mean sap velocity, these data allowed the calculation of overstory water use. Over the experimental period, water use of the overstory decreased with age ranging, on average, from 1.86 mm day(-1) for the 50-year-old plot to 0.81 mm day(-1) for the 230-year-old plot. Mean daily water use for the two intermediate-aged forests was 1.67 and 1.00 mm day(-1), respectively. Annual water use decreased with forest age from 679 mm for the 50-year-old stand to 296 mm for the 230-year-old stand. This difference corresponds to 3.8 x 10(3) m(3) ha(-1). The annual water use of the intermediate-aged stands was 610 and 365 mm for the 90- and 150-year-old stands, respectively.  相似文献   
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Salinity reduces crop yield by limiting water uptake and causing ion‐specific stress. Soybean [Glycine max (L.) Merr.] is sensitive to soil salinity. However, there is variability among soybean genotypes and wild relatives for salt tolerance, suggesting that genetic improvement may be possible. The objective of this study was to identify differences in salt tolerance based on ion accumulation in leaves, stems and roots among accessions of four Glycine species. Four NaCl treatments, 0, 50, 75 and 100 mm , were imposed on G. max, G. soja, G. tomentella and G. argyrea accessions with different levels of salinity tolerance. Tolerant genotypes had less leaf scorch and a greater capacity to prevent Na+ and Cl? transport from soil solution to stems and leaves than sensitive genotypes. Magnitude of leaf injury per unit increase in leaf Na+ or Cl? concentrations was lower in tolerant than in susceptible accessions. Also, plant injury was associated more with Na+ rather than with Cl? concentration in leaves. Salt‐tolerant accessions had greater leaf chlorophyll‐meter readings than sensitive genotypes at all NaCl concentrations. Glycine argyrea and G. tomentella accessions possessed higher salt tolerance than G. soja and G. max genotypes.  相似文献   
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Abstract This study on reef placement involves two aspects: (1) the development of a bioenergetics model for red snapper, Lutjanus campechanus (Poey), in Gulf of Mexico waters off the coast of Alabama, where significant numbers of artificial reefs are thought to exist, and (2) a fuzzy rough set model by which parameters determined from the bioenergetics model can provide a decision tool for optimally spacing artificial reefs during deployment. The bioenergetics and consumption rates of L. campechanus by age class foraging on artificial reefs in the Gulf of Mexico off the coast of Alabama provided input into the fuzzy rule‐based model. After conducting multiple simulations, highest certainty in optimal reef spacing was achieved for reef distances between 0.50 and 0.95 km such that no more than two fit within a 1‐km2 area. Results can inform fisheries managers about placement of artificial reefs to affect the health and survival of reef‐associated species.  相似文献   
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Spermatogonial transplantation will provide a new way to study spermatogenesis in domestic animals, disseminate male genetics and produce transgenic animals, if efficiency can be improved. We evaluated a 'surgical' method for transplanting donor cells into testes of ram lambs, where the head of the epididymis is reflected, and a catheter introduced into the extra-testicular rete testis. We also tested transduction of ram spermatogonia with a lentiviral (LV) vector as a means to identify permanent colonization, and introduce genes into donor cells. Eight ram lambs, 11- to 13-week olds, were the recipients: in five, spermatogonia were injected into one testis, and the contralateral testis was an un-manipulated control: in two, spermatogonia were injected into one testis and the contralateral was sham-injected: in one, both testes were injected. Six lambs received spermatogonia labelled with a cell-tracking dye and these were collected 1 or 2 weeks after transplantation; three lambs received spermatogonia transduced with a LV vector driving the expression of enhanced Green Fluorescence Protein and these were collected after 2 months. Donor cells were detected by immunohistochemistry in tubules of seven of nine recipient testes. Approximately 22% of tubule cross-sections contained donor cells immediately after transplantation, and 0.2% contained virally transduced cells 2 months after transplantation. The onset of spermatogenesis was delayed, and there were lesions in both injected and sham-injected testes. Despite the effects of the surgery, elongated spermatids were present in one recipient testis 2 months after surgery. The results suggest that, after modifying the surgical and transduction techniques, this approach will be a means to produce good colonization by donor spermatogonia in sheep testes.  相似文献   
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