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101.
Extraction and analytical procedures were developed from 1999 to 2005 for the chemical investigation of molybdenum (Mo) in aerial portions of alfalfa ( Medicago sativa L.) grown on a reclaimed mine tailings site at the Highland Valley Copper Mine in British Columbia, Canada. The purification procedures were guided by colorimetric analyses specific for Mo. The Mo levels in freeze-dried plant samples exceeded 100 ppm, which is more than 20 times the maximum level recommended for livestock feed. In contrast to previous work, which detected the inorganic molybdate anion (MoO4(2-)) in alfalfa from the site, the present study identified the major pool of Mo as a chelate bound to malic acid in five sources of plant material. However, the inorganic form of Mo was characterized in aqueous tailings samples, but once imbibed by vegetation, the anion was chelated to the alpha-hydroxy organic acid. Synthetic chelates were synthesized to differentiate the Mo-malate complex from the Mo-citrate by 95Mo NMR. Crystal structure of the synthetic Mo-malate determined that the Mo was bound to two malato ligands as Na 2[MoO2(malate) 2] x 5H2O, which confirmed the structure of the isolates deduced by 95Mo NMR. The chelation of Mo at the site may well explain the apparent lack of long-term clinical effects in cattle grazing the site.  相似文献   
102.
Throughout the world ornamentation of body with mehedi (Lawsonia inermis L.) leaf paste, with the trade name ‘henna body art’ is becoming increasingly popular. The worldwide increasing demand of mehedi leaf encourages many countries to adopt commercial farming of the plant. Farmers living in central Bangladesh recently commenced small-scale mehedi farming, primarily with the purpose of meeting national demand. A total of 182 farmers are engaged in mehedi farming and a study was conducted among 36 of them (a 20% random sample) to explore indigenous management techniques, marketing, livelihood potential and constraints of the enterprise. Farming was reported to be the major primary occupation of the study area. An average of 0.05 ha land of the respondents was used for mehedi cultivation, which constituted 16.7% of their average farm land. The farmers applied their own indigenous technology in every aspect of the farming, using branch cuttings as the only propagation material. The financial analysis indicated that mehedi farming is a profitable and attractive option for rural livelihoods [with an estimated net present value of Tk (Bangladeshi currency unit, 1 US $ = 68 Taka (as of May, 2009).) 179,500 for 0.1 ha plantation]. However, the enterprise faces several constraints, including absence of a nursery for supplying planting materials, storage and effective marketing facilities, available capital for investment, improved technology, and above all, government support. If the government extends cooperation by assisting farmers with training, technology, credit and market development, mehedi farming could become an important revenue-earning enterprise in the small-scale cottage sector of Bangladesh.  相似文献   
103.
Abstract

Aerobic rice is a potential water-wise rice production system, but high weed infestation has threatened its sustainability, which demands an efficient and cost-effective weed management technique. Eight commercial herbicide products were applied singly or as tank-mix or in sequence to evaluate their efficacy, rice selectivity and cost-effectiveness in aerobic rice. The study was conducted under field conditions in Malaysia during 2010/2011 following a randomized complete block design. Most of the herbicide treatments provided excellent weed control, and produced much higher net benefit than weedy or weed-free check. None of the herbicides caused significant phytotoxicity to rice plants. Among the herbicide treatments, sequential application of Cyhalofop-butyl+Bensulfuron at early growth stage followed by Bentazon/MCPA at mid growth stage provided the highest weed control efficiency, productivity and net benefit. Application of Bispyribac-sodium at early growth stage followed by Bentazon/MCPA at mid growth stage performed very close to the above-mentioned treatments. Sequential application of Pretilachlor/safener just after seeding followed by Propanil/Thiobencarb at early growth stage also provided satisfactory results in terms of efficacy and economic return. Since manual weeding was not economic, herbicide rotation using the above chemicals may be recommended for effective weed management in aerobic rice.  相似文献   
104.
SUMMARY A retrospective study of 46 horses with retropharyngeal lymph node (RPLN) infection presented to the Rural Veterinary Centre between 1977 and 1992 was undertaken. Horses aged less than one year were most commonly represented (46%). Thirty-nine percent of cases had been exposed to horses with confirmed or suspected strangles (Streptococcus equi subsp equi infection) within the previous 8 weeks. Most frequent signs were unilateral or bilateral swelling of the throat region (65%), respiratory stertor/dyspnoea (35%), purulent nasal discharge (20%), inappetence and signs of depression (15%), and dysphagia (9%). All horses had a soft tissue density in the retropharyngeal region on radiographs. Rhinopharyngoscopy, ultrasonography, haematology as well as cytological and microbial analysis of material aspirated from the soft tissue swelling facilitated diagnosis in some horses. Fifteen horses (33%) were treated with procaine penicillin intramuscularly for 4 to 7 days followed by oral trimethoprim-sulphadimidine for 7 to 14 days. Non-steroidal anti-inflammatory drugs were administered to 6 horses. Four required tracheostomy for severe respiratory distress. The 15 horses treated medically responded to treatment and were discharged from hospital. Three horses (6%) with mild signs received no treatment and recovered uneventfully. Twenty-eight horses (61%) underwent general anaesthesia and surgical drainage of a RPLN abscess. Nineteen received procaine penicillin G for 4 to 7 days. Four of the nine horses that did not receive antibiotic treatment after surgery required further surgical drainage 10 days to 7 weeks after the initial surgery . Limited follow-up information was available for 37 horses. Thirty-two horses were considered to have made complete recovery, 3 horses had died through misadventure and 2 had been euthanased because of chronic ill-thrift .  相似文献   
105.
Objective To compare the postoperative analgesic and sedative properties of buprenorphine and morphine in cats. Study Design Prospective, randomized, blinded study. Animals Thirty‐two domestic cats undergoing surgery. Methods Cats received pre‐anaesthetic medication with acepromazine (0.05 mg kg?1) given intramuscularly and were randomly allocated to group M and given morphine (0.1 mg kg?1) intramuscularly (IM) or to group B and given buprenorphine (0.01 mg kg?1) IM. Anaesthesia was induced with propofol and maintained with halothane in oxygen and nitrous oxide. Pain and sedation scores using visual analogue scales, and heart and respiratory rates, were measured immediately before, and 30, 60, 120, 180, 300 and 420 minutes after anaesthesia. Results Pain scores were significantly lower at 60, 120 and 180 minutes after anaesthesia in group B. Group B also had higher heart rates at 30 minutes. There were no other statistically significant differences between the groups. Clinical relevance Buprenorphine (0.01 mg kg?1) appeared to provide better postoperative analgesia than morphine (0.1 mg kg?1) and may also have a longer duration of action.  相似文献   
106.
A cat was diagnosed with nasopharyngeal stenosis on the basis of clinical signs, survey and contrast radiography, endoscopy and magnetic resonance imaging. The condition was successfully managed with repeated balloon dilatation.  相似文献   
107.
The signalment, history, clinical signs, radiographic findings, and surgical findings of 25 consecutive animals that had sinography were reviewed to assess the contribution made by sinography to diagnosing and surgically managing draining tracts in small animals. There were 23 dogs and 2 cats; a variety of breeds and both sexes were represented (18 males, 7 females). Before referral the mean duration of clinical signs was 9.8 months (range, 0.5 to 33 months) and a mean of 2.0 surgical procedures (range, 1 to 5) had been performed. Sinuses occurred in a variety of locations, most commonly the neck (10), head (6), and paws (5). The most common cause was foreign body (15). Survey radiographs showed abnormalities in 21 of 26 (78%) instances, including soft-tissue swelling (11), chronic-appearing periosteal reaction on adjacent bones (5), possible foreign body (4), and gas in soft tissues (2). Sinography (or fistulography) enabled definite diagnosis of the cause of the sinus (or fistula) in 15 of 26 (58%) instances and demonstrated 13 of 15 foreign bodies (sensitivity 87%; specificity 100%). Tracts caused by an esophageal perforation and otitis media were also correctly shown by fistulography. In 11 animals, sinography indicated that the position or extent of the lesion was different to that expected on the basis of clinical signs and survey radiographs.  相似文献   
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