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1.
Ming Pei You Brandon Lancaster Krishnapillai Sivasithamparam Martin John Barbetti 《Plant and Soil》2008,302(1-2):203-211
In Australia, in the past, pasture legumes were rotated mainly with cereals, but increasingly these rotations now involve
pasture legumes with a wider range of crops, including legumes. This increasing frequency of the leguminous host in the rotation
system may be associated with increased root rots in legumes in the current pasture-crop rotations. The primary aim of this
study was to see whether the pathogenicity on pasture legumes of strains of Rhizoctonia solani sourced from lupins and cereals (common crops in rotation with pastures) is associated with increased incidence of root rots
in pasture legumes in the disease conducive sandy soils of the Mediterranean regions of southern Australia. The second aim
was to determine sources of resistance among newly introduced pasture legumes to R. solani strains originating from rotational crops as this would reduce the impact of disease in the pasture phase. Fifteen pasture
legume genotypes were assessed for their resistance/susceptibility to five different zymogram groups (ZG) of the root rot
pathogen R. solani under glasshouse conditions. Of the R. solani groups tested, ZG1–5 and ZG1–4 (both known to be pathogenic on cereals and legumes) overall, caused the most severe root
disease across the genotypes tested, significantly more than ZG6 (known to be pathogenic on legumes), in turn significantly
>ZG4 (known to be pathogenic on legumes) which in turn was >ZG11 (known to be pathogenic on legumes including tropical species).
Overall, Ornithopus sativus Brot. cvs Cadiz and Margurita, Trifolium michelianum Savi. cvs Paradana and Frontier and T. purpureum Loisel. cv. Electro showed a significant level of resistance to root rot caused by R. solani ZG11 (root disease scores ≤1.2 on a 1–3 scale where 3 = maximum disease severity) while O. sativus cvs Cadiz and Erica showed a significant level of resistance to root rot caused by R. solani ZG4 (scores ≤1.2). O. compressus L. cvs Charano and Frontier, O. sativus cv. Erica, and T. purpureum cv. Electro showed some useful resistance to root rot caused by R. solani ZG6 (scores ≤1.8). This is the first time that cvs Cadiz, Electro, Frontier, Margurita and Paradana have been recognised
for their levels of resistance to root rot caused by R. solani ZG11; and similarly for cvs Cadiz and Erica against ZG4; and for cvs Charano, Erica, and Electro against ZG6. These genotypes
with resistance may also serve as useful sources of resistance in pasture legume breeding programs and also could potentially
be exploited directly into areas where other rotation crops are affected by these R. solani strains. None of the tested genotypes showed useful resistance to R. solani ZG1–4 (scores ≥2.0) or ZG1–5 (scores ≥2.5). This study demonstrates the relative potential of the various R. solani ZG strains, and particularly ZG1–4, ZG1–5, ZG4 and ZG6 to attack legume pastures and pose a significant threat to non-pasture
crop species susceptible to these strains grown in rotation with these pasture legumes. Significantly, the cross-pathogenicity
of these strains could result in the continuous build-up of inoculum of these strains that may seriously affect the productivity
eventually of legumes in all rotations. In particular, when choosing pasture legumes as rotation crops, caution needs to be
exercised so that the cultivars deployed are those with the best resistance to the R. solani ZGs most likely to be prevalent at the location. 相似文献
2.
Household‐level correlates of children's physical activity levels in and across 12 countries
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Deirdre M. Harrington Fiona Gillison Stephanie T. Broyles Jean‐Philippe Chaput Mikael Fogelholm Gang Hu Rebecca Kuriyan Anura Kurpad Allana G. LeBlanc Carol Maher Jose Maia Victor Matsudo Timothy Olds Vincent Onywera Olga L. Sarmiento Martyn Standage Mark S. Tremblay Catrine Tudor‐Locke Pei Zhao Peter T. Katzmarzyk for the ISCOLE Research Group 《Obesity (Silver Spring, Md.)》2016,24(10):2150-2157
3.
Although cryopreservation has been developed and optimized over the past decades, it causes various stresses, including cold shock, osmotic stress, and ice crystal formation, thereby reducing fertility. During cryopreservation, addition of cryoprotective agent (CPA) is crucial for protecting spermatozoa from freezing damage. However, the intrinsic toxicity and osmotic stress induced by CPA cause damage to spermatozoa. To identify the effects of CPA addition during cryopreservation, we assessed the motility (%), motion kinematics, capacitation status, and viability of epididymal spermatozoa using computer-assisted sperm analysis and Hoechst 33258/chlortetracycline fluorescence staining. Moreover, the effects of CPA addition were also demonstrated at the proteome level using two-dimensional electrophoresis. Our results demonstrated that CPA addition significantly reduced sperm motility (%), curvilinear velocity, viability (%), and non-capacitated spermatozoa, whereas straightness and acrosome-reacted spermatozoa increased significantly (p < 0.05). Ten proteins were differentially expressed (two decreased and eight increased) (>3 fold, p < 0.05) after CPA, whereas NADH dehydrogenase flavoprotein 2, f-actin-capping protein subunit beta, superoxide dismutase 2, and outer dense fiber protein 2 were associated with several important signaling pathways (p < 0.05). The present study provides a mechanistic basis for specific cryostresses and potential markers of CPA-induced stress. Therefore, these might provide information about the development of safe biomaterials for cryopreservation and basic ground for sperm cryopreservation. 相似文献
4.
Effect of capsulectomy on the hemodynamics and viability of random-pattern skin flaps raised on expanded skin in the pig 总被引:2,自引:0,他引:2
S F Morris C Y Pang J Mahoney N Lofchy I L Kaddoura R Patterson F Lista 《Plastic and reconstructive surgery》1989,84(2):314-22; discussion 323-4
Skin flaps constructed on expanded skin usually include the underlying capsular tissue. It has been hypothesized that capsulectomy may jeopardize the viability of the expanded skin flap. The experiments reported herein were designed to test this hypothesis. Specifically, we studied the hemodynamics and viability of random-pattern skin flaps (8 X 20 cm) raised on delayed bipedicle flaps (group A) and on expanded skin pockets with capsulectomy at the time of flap elevation (group B) or with intact underlying capsular tissue (group C). Each group was randomly assigned to each flank in 16 pigs. Skin pockets were expanded by inflation of subcutaneous silicone tissue expanders with sterile saline (299 +/- 7 ml; X +/- SEM) over a period of 3 weeks. At the end of this period, the bipedicle flaps were constructed. Eight days later, random-pattern skin flaps were raised on bipedicle flaps and skin pockets. The length and area of skin flap viability, judged by the fluorescein dye test performed 1 day postoperatively, were not significantly different (p greater than 0.05) among groups A, B, and C (n = 31 to 32). There also were no significant differences (p greater than 0.05) in total skin capillary blood flow measured 1 day postoperatively (A = 2.6 +/- 0.4, B = 2.4 +/- 0.4, and C = 2.7 +/- 0.6 ml/min per flap; n = 15 to 16) and in skin viability assessed 7 days postoperatively (A = 74 +/- 2, B = 75 +/- 2, and C = 76 +/- 2 percent; n = 16) among delayed skin flaps and skin flaps raised on expanded skin pockets with or without capsulectomy. The results of this flap viability study were confirmed in 5 minipigs in a separate experiment. We conclude that capsulectomy did not have a detrimental effect on the hemodynamics and viability of random-pattern skin flaps raised on expanded skin. Furthermore, we hypothesize that skin flaps raised on expanded skin are similar to delayed skin flaps in that the skin blood flow is optimally augmented; therefore, the capsular tissue does not add significant blood supply to the overlying skin. 相似文献
5.
Extracellular levels of 5-hydroxytryptamine (5-HT) and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) were measured in the ventral hippocampus of the awake rat using microdialysis. The basal level of 5-HT in hippocampal dialysates was very close to the detection limit of our assay. However, addition of a 5-HT re-uptake blocker, citalopram, to the perfusion medium resulted in a 3-fold rise of 5-HT levels in dialysates and provided a stable baseline. Under these conditions, extracellular levels of 5-HT and 5-HIAA could be measured up to 11 days after dialysis probe implantation. 5-HT measured in dialysate was Ca2+-dependent both 24 h and 7 days after surgery. In comparison K+-induced depolarization caused a 9-fold increase in 5-HT output 24 h after probe implantation and this effect had disappeared 10 days later, although behavioral activation following K+ application was similar 24 h and 11 days after surgery. Systematic administration of
-trytophan had no significant effect on 5-HT but increased 5-HIAA levels by 90%. These results suggest that in the presence of citalopram, 5-HT in hippocampal dialysates is derived from serotonergic neurones. The microdialysis method appears most useful for measurement of extracellular 5-HT 24–72 h after probe implantation. Finally, our data indicate that extracellular 5-HIAA mainly reflects intraneuronal metabolism of 5-HT prior to release. 相似文献
6.
Propranolol antagonizes hypotension induced by alpha-blockers but not by sodium nitroprusside or methacholine 总被引:1,自引:0,他引:1
A pressor response has been observed with propranolol, a nonselective beta-adrenoceptor antagonist, in animals given a nonselective alpha-adrenoceptor antagonist. This study investigates whether a pressor response to propranolol occurs in conscious unrestrained rats following a hypotensive response induced by phentolamine (nonselective alpha-antagonist), prazosin (selective alpha 1-antagonist) and (or) rauwolscine (selective alpha 2-antagonist), sodium nitroprusside (smooth muscle relaxant), or methacholine (muscarinic agonist). The rats were subjected to a continuous infusion of a hypotensive agent or normal saline followed by i.v. injection of propranolol. The infusion of phentolamine significantly decreased mean arterial pressure (MAP). Subsequent injection of propranolol restored MAP to the control level. Prazosin and rauwolscine each caused a small but not significant decrease in MAP which was reversed by propranolol. Concurrent infusions of prazosin and rauwolscine caused a significant decrease in MAP. Subsequent injection of propranolol caused a large pressor response which increased MAP to 20% above control MAP prior to the administration of drugs. Nitroprusside or methacholine each caused a significant decrease in MAP, but the hypotension was not antagonized by propranolol. The concurrent infusions of a low dose of nitroprusside and prazosin caused a significant decrease in MAP which was reversed by propranolol. The infusion of saline did not alter MAP, and propranolol did not cause a pressor response. It is concluded that propranolol antagonizes the hypotensive effect of an alpha-blocker but not that of sodium nitroprusside or methacholine. Our results suggest the presence of a specific interaction between alpha- and beta-antagonists. 相似文献
7.
8.
9.
Inka Brockhausen Arthur A Grey Henrianna Pang Harry Schachter Jeremy P Carver 《Glycoconjugate journal》1988,5(4):419-448
Sixteen asparagine-linked oligosaccharides ranging in size from (Man)2(GlcNAc)2 (Fuc)1 to (GlcNAc)6(Man)3(GlcNAc)2 were obtained from human 1-acid glycoprotein and fibrinogen, hen ovomucoid and ovalbumin, and bovine fetuin, fibrin and thyroglobulin by hydrazinolysis, mild acid hydrolysis and glycosidase treatment. The oligosaccharides hadN-acetylglucosamine at the reducing termini and mannose andN-acetylglucosamine residues at the non-reducing termini and were prepared for use asN-acetylglucosaminyltransferase substrates. Purification of the oligosaccharides involved gel filtration and high performance liquid chromatography on reverse phase and amine-bonded silica columns. Structures were determined by 360 MHz and 500 MHz proton nuclear magnetic resonance spectroscopy, fast atom bombardment-mass spectrometry and methylation analysis. Several of these oligosaccharides have not previously been well characterized.Abbreviations bis
bisecting GlcNAc
- DMSO
dimethylsulfoxide
- FAB
fast atom bombardment
- Fuc
l-fucose
- Gal
d-galactose
- GLC
gas-liquid chromatography
- GlcNAc or Gn
N-acetyl-d-glucosamine
- HPLC
high performance liquid chromatography
- Man or M
d-mannose
- MES
2-(N-morpholino)ethanesulfonate
- MS
mass spectrometry
- NMR
nuclear magnetic resonance
- PIPES
piperazine-N,N-bis(2-ethane sulfonic acid)
the nomenclature of the oligosaccharides is shown in Table 1. 相似文献
10.