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21.
开发更高效的生物炭肥料提高辣椒产量和质量   总被引:1,自引:0,他引:1  
Utilization of biochar at high application rates can increase soil C and crop yields, decrease greenhouse gas emissions and reduce nutrient run-off from soils. However, the high application rate of 10 t ha-1may not return a profit to the farmer due to the high cost of biochar. In this study biochar was modified through pre-treating the biomass and post-treating with phosphoric acid, minerals and different chemical fertilisers to study the effects of two new enhanced biochar fertilisers on the yield and quality of green pepper in a field experiment with 5 fertilisation treatments and 3 replications. The two new biochar fertilisers significantly(P 0.05) increased the yield of green pepper(11.33–11.47 t ha-1), compared with the conventional chemical fertiliser(9.72 t ha-1). The biochar fertiliser treatments improved the vitamin C content of green pepper from 236.99 to 278.28 mg kg-1, and also significantly(P 0.05) reduced the nitrate content from 132.32 to 101.92 mg kg-1, compared with chemical fertiliser. This study indicated that, compared to the use of conventional chemical fertiliser, all of the biochar fertiliser treatments could significantly improve the yield and quality of green pepper.  相似文献   
22.
Urinary bladder cancer is difficult to treat accurately with fractionated radiation therapy (RT) due to daily positional changes of the bladder and surrounding soft‐tissue structures. We quantified the daily motion experienced by the canine bladder with patients in dorsal vs. sternal vs. lateral recumbency. We also described the dose distribution for three different planning target volume expansions (5, 10, and 15 mm) for each of the three positions to ensure adequate bladder dose and minimize irradiation of nearby healthy tissues. Analysis was based on data from retrospective daily cone‐beam computed tomography (CT) (CBCT) images obtained for positioning of canine patients undergoing routine RT. Organs of interest were contoured on each CBCT data set and the images, along with the contours, were registered to the original planning CT. All measurements were made relative to the planning CT and dosimetric data for the organs of interest was determined using a dose volume histogram generated from sample parallel‐opposed beam configuration. There was a wide range in bladder position throughout treatment. The least amount of bladder variation and the lowest rectal dose was with dogs in lateral recumbency. It was also determined that a margin of 10 mm would allow for sufficient dose to be delivered to the bladder while minimizing rectal dose.  相似文献   
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Unilateral cranial cruciate ligament excision and fibular head transposition (FHT) were performed on 30 adult dogs. Vertical ground reaction forces were determined using force plate data before and after surgery. Cranial drawer motion, tibial rotation, and varus-valgus motion were measured at monthly intervals. Radiographic, gross, and histological examinations of the stifle joints that had been operated on were performed 3 weeks, 4 months, and 10 months after surgery. A scoring system was used to evaluate lameness, osteophyte formation, and meniscal damage. Rank correlation coefficients were calculated between variables tested in pairs. Cranial drawer motion and abnormal tibial rotation were present in all of the joints that had been operated on. Peak vertical force and associated impulse were not restored during the study time period. Meniscal damage was noted in 25% of the dogs at month 4 and in 50% of the dogs at month 10. Progressive gross and histological deterioration of the articular cartilage was observed in all joints. Positive correlations were noted between the degree of stifle joint instability and meniscal injury or radiographic changes. FHT did not control cranial drawer motion and rotational instability, was not successful in restoring limb function, and did not prevent joint degeneration, especially meniscal damage.  相似文献   
25.
This study was undertaken to determine what difference, if any, occurred when autogenous cancellous bone was placed in the medullary canal of a fresh, 4-cm cortical allograft compared to a fresh cortical allograft alone. Twelve mature dogs were used. A tubular cortical graft was placed in the midshaft of both tibias. The right tibia received the combination graft while the left tibia received a fresh cortical allograft only. Study periods ranged from one week to 17 weeks. The progress of the grafts was assessed by technetium-99m radionuclide bone scans, radiographs, gross and histological examination, and tetracycline labeling. Results indicate that autogenous cancellous bone placed in the medullary canal of a fresh cortical allograft was beneficial to the ingrowth of new blood vessels and incorporation of the cortical graft.  相似文献   
26.
The caudal cruciate ligament (CaCL) of one stifle joint in seven dogs was transected and a 2 to 4 mm section was removed. Six months after surgery, none of the dogs were lame. Thigh muscle circumference, stifle range of motion, and internal tibial rotation in the operated limb were not significantly different from the preoperative measurements or the contralateral, unoperated limb. A caudal drawer motion was consistently present in the stifle joints with a transected CaCL. A radiographic evaluation of the operated stifle joints did not reveal osteoarthritic changes; four of seven stifle joints had an irregular fat pad 6 months after surgery. Results of a joint fluid analysis revealed a slight increase in synovial cells within treated stifle joints; inflammatory cells were not observed. The only gross morphologic change in stifle joints with a severed ligament was enlarged knobby remnants of the CaCL. Articular cartilage defects or osteophytes were not observed. Results of a histologic examination of the CaCL remnants revealed synovial cellular capping and intraligamentous fibroplasia. Based on a limited number of dogs, it was concluded that isolated transection of the CaCL produced minimal clinical and pathologic changes in the stifle joint during a 6 month period.  相似文献   
27.
<正>Dear Editor,Biochar has been used as an input in the animal farming industry since 2010 (Gerlach and Schmidt, 2012; Schmidt et al., 2019). Several studies have documented the positive effects of biochar, used as a feed supplement, on both livestock and soil health. Schmidt et al.(2019) examined 112studies, in which the addition of a small amount of biochar to fodder improved the animal immune system,  相似文献   
28.
The influence of different combinations of illumination and shaking on the growth dynamics, pathogenicity and toxin production of the fungus Fusarium oxysporum f. sp. orthoceras, a biocontrol agent of Orobanche cumana, was studied. The fastest biomass accumulation was obtained under shaking, with or without illumination, with the highest biomass obtained after 3–4 weeks of growth. The biological activity of chloroform extracts of the culture filtrate was characterised: it contained at least two main toxic metabolites that caused necrosis and wilting of various plants and led to mortality of germinating seeds of O. cernua, O. aegyptiaca, O. ramosa and O. cumana. The highest toxic activity of the chloroform extract was obtained under illumination without shaking after 3–4 weeks of growth. The two toxic metabolites were purified and identified as fusaric acid (FA) and 9,10‐dehydrofusaric acid (DFA). Both FA and DFA production began in the first week of growth, increasing gradually to their maxima after 4 weeks. The highest level of pathogenic activity of the fungus was obtained after three or more weeks of fungal growth. It can be concluded that in order to produce high levels of toxin and pathogenic activity, the fungus should be grown under illumination without shaking for 4 weeks.  相似文献   
29.
Unilateral triple pelvic osteotomy was performed with three variations in technique on canine cadaver pelves. The following variables were studied: the angle of the ilial osteotomy (perpendicular to the long axis of the ilium and 10d?, 20d?, and 30d? off perpendicular); the degree of axial rotation (20d?, 30d?, and 45d?); and the type of fixation (canine pelvic osteotomy plate [CPOP] or a 2.7-mm dynamic compression plate [DCP]). Structural changes measured were the pelvic inlet and acetabular area, interischiatic tuberosity distance, and degree of acetabular version. Means and standard error of the means were determined for all pelvic measurements and were analyzed by three-way analysis of variance (P < .05). As the axial rotation increased from 20d? to 45d? an ilial osteotomy angled 10d?, 20d?, or 30d? resulted in a significantly greater decrease in the pelvic inlet area and significantly less deviation of the interischiatic tuberosity distance and degree of acetabular version from normal than an osteotomy directed perpendicular to the long axis of the ilium. Compared with the CPOP, as the axial rotation increased from 20d? to 45d?, the DCP resulted in a significantly greater decrease in the pelvic inlet area, an increase in the interischiatic tuberosity distance and degree of acetabular version, and less of an increase in the acetabular area. The results of this study suggest that to maximize dorsal acetabular coverage, while minimizing disruption of normal pelvic architecture, a CPOP and an ilial osteotomy angled 10d? to 30d? are preferred for all degrees of axial rotation.  相似文献   
30.
Abstract— A 5-year-old mongrel dog developed necrolytic migratory erythema secondary to a glucagon-secreting α cell tumor. The dog was anemic, glucose intolerant, and hyperglucagonemic but liver function tests were within normal limits. Metastatic tumor cells were found in the liver but the primary tumor was not identified.
Résumé— Un chien croisé mâle de 5 ans a développé un Erythème nécrolytique migrant secondaire à un glucayonome. L'animal était anémié, présentait une intolérance au glucose et une hyperglucagonémie, avec des tests fontcionnels hépatiques dans les limites des valeurs usuelles. Des cellules métastaiques tumorales ont été retrouvées dans le foie, mais la tumeur primitive n'a pas été identifiée.
Zusamenfassung —Ein 5 Jahr alter Mischingshund entwickelte sekundär auf einen Glukagon-sezernierenden Tumor ein nekroyltisches Erythema migrans. Das Tier war anämisch, Glukose-intolerant und hyperglukagonämische; die Leberfunktionstests befanden sich jedoch innerhalb normaler Grenzwerte. Matastatische Tumorzellen waren in der Leber nachweisbar, der Primärtumor konnte jedoch nicht identifizert werden.
Resumen  Un perro cruzado de 5 años desarrollo un eritema necrolítico migratorio, secundario a un tumor de celulas secretoras de glucógeno. El perro era anémico, presentaba intolerancia a la glucosa, e hiperglucogenia, pero los resultados de los tests que evaluaban la función hepática feuron normales. Se encontraron células tumorales metastásicas procedentes del hígado, pero el tumor primario no se identificó. Se encontraron células tumorales metastásicas procedentes del hígado, pero el tumor primario no se identificicó.  相似文献   
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