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排序方式: 共有732条查询结果,搜索用时 156 毫秒
71.
72.
He ZD Qiao CF Han QB Cheng CL Xu HX Jiang RW But PP Shaw PC 《Journal of agricultural and food chemistry》2005,53(7):2424-2428
Cassia bark or cortex cinnamomi, the dried stem bark of Cinnamomum cassia Presl. (Lauraceae), is a popular natural spice and a commonly used herb in traditional Chinese medicine. However, adulterants are frequently found in the market. In this study, 44 samples of Cassia bark including bark from seven related Cinnamomum species were collected from fields and market. Four characteristic components, cinnamaldehyde, cinnamic acid, cinnamyl alcohol, and coumarin were determined by RP-HPLC, and a fingerprint comprised of five markers was established. These results showed that cassia barks contained high contents of cinnamaldehyde (13.01-56.93 mg/g). The highest content of cinnamaldehyde (up to 93.83 mg/g) was found in debarked cortex, which is traditionally regarded as having the best quality in local herb shops. In contrast, the adulterants from the other Cinnamomum species, C. wilsonii Camble, C. japonicum Sieb., C. mairei Levl. and C. burmanii (Nees) Blume, contained low contents of cinnamaldehyde (<2.00 mg/g). The content of cinnamaldehyde in C. loureirii Nees was comparable to that in C. cassia. It is suggested that five characteristic peaks by HPLC are suitable for distinguishing genuine cassia bark from the adulterants and could be applied in the quality control of this commodity. 相似文献
73.
Dong-Lin Wang Ahindra Nag Guan-Chun Lee Jei-Fu Shaw 《Journal of agricultural and food chemistry》2002,50(2):262-265
Among 10 lipases tested, Candida rugosa lipase exhibited the best ability to catalyze the resolution of dl-menthol in organic solvent. The lipase was immobilized on different carriers, and the experiment was carried out with different acyl donors. The high yield and optical purity of the product were achieved in cyclohexane with valeric acid as acyl donor using C. rugosa lipase immobilized on DEAE-Sephadex A-25. The conversion of dl-menthol depended on the water content of immobilized lipase and on the pH of the aqueous solution from which lipase was immobilized. The operational stability of the DEAE-Sephadex A-25 immobilized lipase in catalysis of the esterification reaction showed that >85% activity remained after 34 days of repeated use. The resolution of racemic menthol in organic medium catalyzed by immobilized C. rugosa lipase-catalyzed esterification is very convenient, and it represents a significant improvement in the use of enzyme for the preparative production of optically active menthol. This process is readily applicable to large-scale preparation. 相似文献
74.
SUMMARY Intra-articular injection of sodium monoiodoacetate (MIA) was investigated as an agent for chemical arthrodesis of the distal hock joints in the horse. Five horses diagnosed with either spavin (three horses), a small tarsal bone fracture or a failed surgical arthrodesis, had 150 mg of MIA injected into the tarsometatarsal (TMT) joint of the affected hock(s). Eight joints were treated in the five horses. Follow-up evaluation by clinical and radiological examination took place over 9 to 14 months. Two of the five horses were sound at the conclusion of the study and one horse, although lame after flexion, was considered by the owner to have been treated successfully. One of eight TMT joints showed complete radiographic fusion. Complications after treatment included pain, chronic lameness and swelling. It was concluded that chemical arthrodesis using this technique can not be recommended as being a superior treatment as compared with surgical arthrodesis at this time but is deserving of further clinical evaluation. 相似文献
75.
Deficiencies of the vitamin K-dependent coagulation factors were identified in a Devon rex cat which had bled after castration. Haemorrhage was controlled by plasma transfusion. Clotting times were normalised by oral administration of vitamin K. This report confirms the existence of this bleeding disorder in a Devon rex cat in the United Kingdom. 相似文献
76.
Antimicrobial susceptibility and serotypes of Actinobacillus (Haemophilus) pleuropneumoniae recovered from Missouri swine 总被引:4,自引:0,他引:4
W H Fales L G Morehouse K R Mittal C Bean-Knudsen S L Nelson L D Kintner J R Turk M A Turk T P Brown D P Shaw 《Journal of veterinary diagnostic investigation》1989,1(1):16-19
The antimicrobial susceptibility of 73 Actinobacillus (Haemophilus) pleuropneumoniae isolates from swine in Missouri was determined with a microdilution minimal inhibitory concentration test system. Serotyping was accomplished by means of co-agglutination. Serotype 1 (39/73) and serotype 5 (30/73) were commonly found, whereas serotype 7 (4/73) was infrequently encountered. Most isolates (MIC90) were found susceptible to ampicillin (amoxicillin), cephalothin, penicillin, erythromycin, gentamicin, and kanamycin. Marked resistance was found with oxytetracycline, tylosin, and sulfadimethoxine. The data indicate that use of ampicillin (amoxicillin) or penicillin may correlate well with the favorable outcome of treatment. 相似文献
77.
78.
K A Roby V B Reef D P Shaw C R Sweeney 《Journal of the American Veterinary Medical Association》1986,189(3):305-308
A 15-year-old, Standardbred broodmare with an aortic sinus aneurysm developed rupture of the aneurysm with subsequent rupture of a tricuspid valve chorda tendinae, tricuspid regurgitation, acute right-sided congestive heart failure, and pulmonary thromboembolism. Shunting of blood from the aorta through the ruptured aneurysm into the right ventricle resulted in decreased renal perfusion and acute renal failure. Initially, treatment of the mare with analgesics, fluids, and digoxin resulted in clinical improvement, but the mare's condition deteriorated after 8 days and the mare was euthanatized due to unrelenting pain and a poor prognosis. Echocardiography was useful in diagnosis of the cardiac disease in the broodmare. 相似文献
79.
Brook charr 15 months old were introduced in 1985 into one of two self-contained basins of Batchawana Lake, Ontario, Canada, where they survived and reproduced. Population survival rates (ages ≥ 1) remained high (>50%) from 1986 to 1992. Annual growth rates peaked (Gx=3.1) the year following their introduction, and remained between 0.8 and 1.6 thereafter. Brook charr biomass (B) was highest, ~ 55 kg ~ ha?1 in 1987 and 1990, and production (P) gradually declined from 80–90 in 1986–1987 to ~ 30 kg-ha?1 -year?1 in 1990–1991. Initial high P:B ratios for brook charr, ~ 3.0, declined and stabilized to ~ 1.3 in the third year after introduction. 相似文献
80.
Cockroach control in sewers in Singapore using bioresmethrin and piperonyl butoxide as a thermal fog
Cockroaches have considerable importance as vectors of disease. In tropical areas, large populations of Periplaneta americana may be found in sewers and the refuse chutes of large apartment blocks. These cockroach populations are not accessible to residual insecticide treatment with sprays but may be controlled with thermal fogs of pyrethroids. An experiment on the use of bioresmethrin (5-benzyI-3-furyimethyl-(+)-trans chrysanthemate) as 0.15% and 0.25% w/v solutions with equal amounts of synergist in kerosene discharged from a TIFA fog generator was made at Toa Payoh in Singapore. Effective control was obtained with 0.15% bioresmethrin plus 0.55% piperonyl butoxide in kerosene blown into the sewers and waste chutes initially, at four weeks, at eight weeks later and then followed by treatment every two months. 相似文献