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排序方式: 共有101条查询结果,搜索用时 31 毫秒
11.
12.
Comparison of three techniques for the diagnosis of urinary tract infections in dogs with urolithiasis 总被引:1,自引:0,他引:1
OBJECTIVES: To identify an appropriate sampling technique(s) to accurately detect the bacteria causing urinary tract infections in dogs with urolithiasis. METHODS: Twenty-one dogs with urolithiasis were included in the study. Three types of samples were taken from each dog. Urine was collected by cystocentesis, and a urinary bladder mucosal biopsy and urolith were retrieved during cystotomy. The samples were then cultured on blood agar and MacConkey's agar to identify the bacteria associated with urinary tract infections. RESULTS: Bacterial urinary tract infection was found in 16 cases (76.19 per cent). The most prevalent bacteria found to cause urinary tract infection were Escherichia coli (n=7), followed by coagulase-positive Staphylococcus species (n=4), Klebsiella pneumoniae (n=2), Pseudomonas aeruginosa (n=2) and Proteus mirabilis (n=1). In the case of a positive urine culture, the same bacteria were also cultured from the urinary bladder mucosal biopsy alone or from both the urinary bladder mucosal biopsy and urolith. However, in the case of a negative urine culture, bacteria were found to be present in the urinary bladder mucosal biopsy or urolith cultures in 23.81 per cent of dogs. The uroliths that gave positive culture results were either infection-induced uroliths composed of struvite and calcium carbonate phosphate, ammonium acid urate only or metabolic uroliths composed of calcium oxalate and calcium phosphate, or calcium phosphate only. All the uroliths that gave negative culture results were metabolic uroliths composed of calcium oxalate and/or calcium phosphate, and uric acid and calcium phosphate. CLINICAL SIGNIFICANCE: When the culture from the urine obtained by cystocentesis is negative, cultures of urinary bladder mucosal biopsy and urolith are recommended in dogs with urolithiasis in order to accurately assess the microbiological status of the urinary tract. 相似文献
13.
G. Andrew Stainback Michel Masozera Athanase Mukuralinda Puneet Dwivedi 《Small-Scale Forestry》2012,11(3):285-300
The perception of Rwandan government officials, NGOs, and extension specialists about smallholder agroforestry adoption as a strategy for smallholder farmers in Rwanda was investigated using a strengths, weaknesses, opportunities, and threats analysis framework combined with the analytical hierarchy process. Results indicate that smallholder agroforestry is viewed positively as a suitable strategy for Rwandan smallholder farmers. The most important positive features were the potential for increased agricultural output from agroforestry and a favorable policy environment in Rwanda supporting sustainable agriculture. Results also indicate that there needs to be better coordination of various efforts to promote agroforestry and stronger extension services for smallholder farmers. Carbon offset markets and other environmental service markets were seen as a potential opportunity for smallholder agroforestry. However, the results also indicate that there is substantial uncertainty and skepticism concerning how such markets would benefit smallholder farmers who adopted agroforestry. 相似文献
14.
Moderate to high heterosis for yield and ten related characters was studied in 45 crosses involving six indica (I) and four
tropical japonica (J) varieties of rice under three (E1-optimum sowing and high fertility, E2-both optimum sowing and fertility and E3- late sowing and high fertility) environments. Trends of magnitude of heterosis for grain yield and plant height were I/J
> I/I > J/J and for days to 50% flowering I/J > J/J > I/I hybrids. Estimates of standard heterosis (%) for grain yield were
–64.5 to 146.1 in E1, –70.4 to 82.2 in E2 and –67.2 to 63.8 in E3. Environment E1 seemed to be more favorable for higher heterosis expression than others. Higher heterosis in yield also accompanied heterosis
in panicle number, dry matter and spikelet and grain number per panicle. Most estimates for days to flower were negative.
Heterotic I/J hybrids also recorded maximum heterosis for earliness. Moderate to low standard heterosis for plant height across
environments (2.0 to 13.7%) was recorded. Hybrids were identified in specific environments for direct exploitation
in hybrid breeding. Hybrids B4116 / Sarjoo 52, B4122 / Pant Dhan 4 and B4122 / Narendera 359 were more stable than others
over three environments.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
15.
Reconstructing past ocean pH-depth profiles 总被引:1,自引:0,他引:1
Measurement of boron isotope compositions in species of planktonic foraminifera that calcified their tests at different depths in the water column are used to reconstruct the pH profile of the upper water column of the tropical ocean. Results for five time windows from the middle Miocene to the late Pleistocene indicate pH-depth profiles similar to that of the modern ocean in this area, which suggests that this method may greatly aid in our understanding of the global carbon cycle. 相似文献
16.
ZF Ren ZP Huang JW Xu JH Wang P Bush MP Siegal PN Provencio 《Science (New York, N.Y.)》1998,282(5391):1105-1107
Free-standing aligned carbon nanotubes have previously been grown above 700 degreesC on mesoporous silica embedded with iron nanoparticles. Here, carbon nanotubes aligned over areas up to several square centimeters were grown on nickel-coated glass below 666 degreesC by plasma-enhanced hot filament chemical vapor deposition. Acetylene gas was used as the carbon source and ammonia gas was used as a catalyst and dilution gas. Nanotubes with controllable diameters from 20 to 400 nanometers and lengths from 0. 1 to 50 micrometers were obtained. Using this method, large panels of aligned carbon nanotubes can be made under conditions that are suitable for device fabrication. 相似文献
17.
S. Gopala Krishnan N. K. Dwivedi J. P. Singh 《Genetic Resources and Crop Evolution》2011,58(7):961-966
Crop domestication has lead to the selection of a wide range of traits that distinguish domesticated crops from their wild
ancestors. Over the past four decades, concerted efforts by archaeologists and geneticists have provided novel insights into
the domestication of crops. However, minor crops are rarely a subject for intensive domestication studies and very less is
known on the domestication of guar [Cyamopsis tetragonoloba (L.) Taub.] except the trans-domestication hypothesis. The hypothesis proposes that the domestication of guar took place
in recent times in the dry areas of the northwestern region of Indo-Pakistan subcontinent and the African wild species, C. senegalensis Guill. et Perr., as its ancestor. However, the process by which the wild species was domesticated is not fully understood.
The present paper describes the exploration, collection and in situ characterization of the primitive weedy forms of guar that could be the missing link between the wild and cultivated species.
Adak guar is found to grow along with cultivated guar as a weed and is characterized by several primitive characters, prominent
among which are spreading habit, small inedible pods which shatter at maturity, hard seed coat and seed dormancy. A total
of 66 germplasm collections of these primitive weedy forms of guar have been made from naturally occurring populations in
the arid regions of northwestern India. Systematic studies involving these primitive weedy forms can help in understanding
the domestication bottlenecks and in utilizing the genetic variation lost during the process of domestication for the improvement
of cultivated guar. 相似文献
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20.
N. K. Dwivedi O. P. Dhariwal S. Gopala Krishnan D. C. Bhandari 《Genetic Resources and Crop Evolution》2010,57(3):443-452
Among the 52 species reported in Cucumis, cucumber and muskmelon are the most important species, extensively cultivated by the human for consumption. Diversity has
been reported in the wild species of Cucumis from India. Considering the status of genetic erosion of the variability in the various species of Cucumis, a total of 121 germplasm accessions of five different Cucumis species were collected through three explorations in the parts of Aravalli ranges of northwestern India. The paper presents
the distribution, collection, extent of variability, associated indigenous traditional knowledge, conservation status of these
Cucumis species and prospects of their utilization in crop improvement. 相似文献