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81.
Uittreksel

In hierdie studie is ondersoek ingestel na die invloed van vier belankrike bosveldbome, naamlik, Acacia Senegal, Acacia tortilis, Boscia albitrunca en Combretum apiculatum op die verspreiding en en produktiwiteit van Panicum maximum.

Die studie is in twee fases uitgevoer: deur middel van veldproewe in die Laar‐ Krokodilrivier‐vallei, noord‐wes van Thabazimbi, en in die glasbuise van die Potchefstroomse Universiteit.

In die veld is opnames deur middel van strookpersele uitgevoer om die verspreiding van Panicum maximum in assosiasie met bogenoemde boomsoorte na te gaan.

In die glasbuise is die groeivermoë van Panicum maximum in grondmonsters wat onder die vier boomsoorte versamel is met dié van grondmonsters wat in oop dele versamel is vergelyk. Die invloed van ligte graad van beskaduïng en twee verskillende vogpeile op die groeivermoë van die proef plante is ter‐selfdertyd ondersoek.

‘n Proef is ook uitgevoer om die groeivermoë van Panicum maximum by toedienings van verskillende peile N, P en K by grond wat in oop dele versamel is te ondersoek.  相似文献   
82.
Abstract

The feasibility and potential of reinforcing veld with legumes in the south‐eastern Transvaal highveld was assessed in a number of trials during the period 1974–84. Experience was gained with regard to methods of establishment, adaptation of legumes to the local environment, responses to fertilization, especially with lime and superphosphate, and the reaction of legumes to fire and grazing. In all, 17 legumes were involved, including the genera Coronilla, Desmodium, Glycine, Lespedeza, Lotus, Macroptilium, Medicago, Neoto‐nonia, Trifolium and Vigna. Only Coronilla varia (crownvetch) showed a satisfactory degree of persistence. However, crownvetch is slow to establish, is intolerant of waterlogging and has a relatively high requirement for lime and phosphate. Considering these features, and the probability of undesirable changes in grass species composition in reinforced veld, it is recommended that intensification be achieved through development of improved pastures for use in conjunction with veld, rather than by means of veld reinforcement.  相似文献   
83.
Abstract

Yields of 17 entries of Lotus corniculatus were measured over two seasons at Ermelo in the south‐eastern Transvaal. There were marked differences between entries in the date of commencement of flowering in the establishment year, the relative abundance of flowers, and the degree of dormany in the winter. Root rot caused by the fungi Fusarium and Phoma caused extensive damage. There were indications that the cultivar Norcen was resistant to the fungi and that Germplasms MO 20 and NC 83 had partial resistance.  相似文献   
84.
Abstract

The pattern of yield response of birdsfoot trefoil (Lotus corniculatus) cv. San Gabriel to soil amendment with lime and superphosphate on a virgin acid soil indicated that this legume is tolerant of local acid soils and moderately tolerant of low levels of extractable phosphorus.  相似文献   
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88.
A three‐year‐old male greyhound was presented with acute onset right forelimb lameness because of medial displacement of the biceps tendon of origin. Ultrasonographic examination confirmed the diagnosis, and a concomitant partial tear of the medial glenohumeral ligament was detected during arthroscopy. To stabilise the biceps tendon, polypropylene mesh was fixed across the intertubercular groove to replace the torn transverse humeral retinaculum. Recovery was uneventful and lameness resolved. Fifteen months later, the dog was presented with medial displacement of the biceps tendon of origin of the left shoulder, and was treated successfully using the same technique.  相似文献   
89.
Carrots ( Daucus carota L.) contain phytochemicals including carotenoids, phenolics, polyacetylenes, isocoumarins, and sesquiterpenes. Purple carrots also contain anthocyanins. The anti-inflammatory activity of extracts and phytochemicals from purple carrots was investigated by determining attenuation of the response to lipopolysaccharide (LPS). A bioactive chromatographic fraction (Sephadex LH-20) reduced LPS inflammatory response. There was a dose-dependent reduction in nitric oxide production and mRNA of pro-inflammatory cytokines (IL-6, IL-1beta, TNF-alpha) and iNOS in macrophage cells. Protein secretions of IL-6 and TNF-alpha were reduced 77 and 66% in porcine aortic endothelial cells treated with 6.6 and 13.3 microg/mL of the LH-20 fraction, respectively. Preparative liquid chromatography resulted in a bioactive subfraction enriched in the polyacetylene compounds falcarindiol, falcarindiol 3-acetate, and falcarinol. The polyacetylenes were isolated and reduced nitric oxide production in macrophage cells by as much as 65% without cytotoxicity. These results suggest that polyacetylenes, not anthocyanins, in purple carrots are responsible for anti-inflammatory bioactivity.  相似文献   
90.
Thirty pheasants which had been reared in captivity for 19 weeks were killed by dislocating the neck and hung for up to 15 d at 10 °C. Microbiological, sensory and chemical assessments were made at 0, 3, 6, 8, 10, 13 and 13 d and this paper reports the microbiological results.

Examination of the duodenum, small intestine and caecum showed very little multiplication of coli‐aerogenes bacteria during hanging, although there was some increase in the numbers of faecal streptococci. Psychrophilic clostridia, mainly Clostridium putrefaciens, were found in the small intestine after 8 d and these organisms increased in number up to the 15th d.

The muscle remained relatively free from bacteria for most of the hanging period, but at 15 d Cl. putrefaciens was found in two out of three muscle samples at io3 and io4 per g.

No signs of spoilage due to greening were observed.

Twelve 16½>‐week‐old chickens were also killed by dislocating the neck and hung without plucking for 12 d at 10 °C with the pheasants. Although initially there were no major differences between the intestinal flora of the chickens and pheasants, faecal streptococci and coli‐aerogenes bacteria multiplied rapidly in the small intestine of the chickens during the first week. Greening occurred around the vent within 5 d.

Reasons for the differences between the two types of bird are discussed, particularly in relation to the diet.  相似文献   

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