THE CHESTNUT BLIGHT AND ITS RELATION TO THE PRINCIPLE OF DISEASE RESISTANCE     

Kelley AP 《Science (New York, N.Y.)》1940,91(2360):290-291

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一起羔羊巴氏杆菌病死亡诊断     

邰晓军  董建华  冯明廷 《畜牧与饲料科学》2004,25(4):i046-46

2003年5月甘肃省肃南县雪泉乡14户牧民共饲养绵羊1778只，产羔1211只，成活1038只，死亡173只，死羔占产羔数的16．67％。其中2户较为严重，死亡羔羊均达40只，分别占产羔数的53.33％和38．33％。  相似文献   

Fisher's Letters     

Dempster AP 《Science (New York, N.Y.)》1991,252(5002):143-144

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Drug abuse policy     

Leccese AP 《Science (New York, N.Y.)》1991,252(5002):12

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Self-Assembled Metal Colloid Monolayers: An Approach to SERS Substrates     

Freeman RG  Grabar KC  Allison KJ  Bright RM  Davis JA  Guthrie AP  Hommer MB  Jackson MA  Smith PC  Walter DG  Natan MJ 《Science (New York, N.Y.)》1995,267(5204):1629-1632

The self-assembly of monodisperse gold and silver colloid particles into monolayers on polymer-coated substrates yields macroscopic surfaces that are highly active for surface-enhanced Raman scattering (SERS). Particles are bound to the substrate through multiple bonds between the colloidal metal and functional groups on the polymer such as cyanide (CN), amine (NH(2)), and thiol (SH). Surface evolution, which can be followed in real time by ultraviolet-visible spectroscopy and SERS, can be controlled to yield high reproducibility on both the nanometer and the centimeter scales. On conducting substrates, colloid monolayers are electrochemically addressable and behave like a collection of closely spaced microelectrodes. These favorable properties and the ease of monolayer construction suggest a widespread use for metal colloid-based substrates.  相似文献   

不同温湿度处理对山核桃授粉期雌雄花发育的影响     

叶立前  袁紫倩  胡俊靖  赵伟明  董建华  李皓  郑国良 《江苏农业科学》2020,48(17):161-165

为更好地揭示山核桃授粉期气象环境因子对雌雄花发育的影响,以离体水培的授粉期山核桃带花枝条为试验材料,设置低温低湿、高温低湿、低温高湿、高温高湿、变温低湿、变温高湿等6个处理,连续观察、拍照、记录不同温湿度条件下雌雄花的发育状况,并测定模拟雨天环境的清水浸泡下花粉活力。研究结果表明,山核桃授粉期温湿度会明显影响雌雄花的发育成熟时间和花粉活力,高温环境可以促进山核桃花器快速发育成熟,缩短发育成熟时间;高湿度环境则会推迟花器的发育成熟,延长发育成熟时间;高温高湿条件下会出现明显的落花现象,花粉活力会随着浸泡时间的延长快速下降。  相似文献   

Culicoides antigen extract stimulates equine blood mononuclear (BMN) cell proliferation and the release of eosinophil adherence-inducing factor(s)     

Mckelvie J  Foster AP  Hamblin AS  Cunningham FM 《Research in veterinary science》2001,70(2):115-122

Intradermal injection of a Culicoides antigen extract (CAgX) induces T lymphocyte and eosinophil accumulation in the skin of horses with sweet itch. Blood mononuclear (BMN) cells from normal ponies proliferate when stimulated by mitogen (phytohaemagglutinin, PHA) or antigen (tetanus toxoid, TT) and, as shown here, release soluble factor(s) that induce eosinophil adherence. CAgX also caused concentration dependent proliferation of BMN cells from sweet itch and normal ponies [stimulation index: 29 (13) and 17 (7) for BMN cells from sweet itch and normal ponies, respectively during the active phase of disease; 4 microg protein ml(-1)CAgX; 168 h]. A heat labile factor(s) which caused eosinophil adherence was also released [sweet itch ponies: 6.0 (1.6) per cent adherence versus 1.3 (0.4) per cent; normal ponies: 6.6 (0.5) per cent adherence versus 0.9 (0.1) per cent for supernatants from CAgX (4 microg protein ml(-1); 48 hours) stimulated versus unstimulated BMN cells, respectively]. These results suggest that soluble proteins released from T lymphocytes could affect eosinophil function in the lesional skin of sweet itch horses.  相似文献   

Pharmacokinetics and microsomal oxidation of praziquantel and its effects on the P450 system in three-month-old lambs infested by Fasciola hepatica     

Giorgi M  Salvatori AP  Soldani G  Giusiani M  Longo V  Gervasi PG  Mengozzi G 《Journal of veterinary pharmacology and therapeutics》2001,24(4):251-259

Praziquantel (PZQ) is a broadly effective trematocide and cestocide, widely employed in veterinary and human medicine. In view of several differences in both its pharmacokinetic profile in different animal species and in the cytochrome P450-dependent system between ruminant and nonruminant species, the present study was undertaken to determine the pharmacokinetics of this drug, its effects on the P450 system and the involvement of cytochrome P450 in its metabolism in 3-month-old lambs infested by Fasciola hepatica. Following both oral and i.m. administration, PZQ disposition was best described by a linear one-compartment open model with a rapid absorption and elimination. Although the PZQ dose used by the i.m. route was only half of that used by the oral route, the mean PZQ plasma concentration was higher after i.m. than after oral treatment. Oral treatment with 30 mg/kg/day of PZQ did not modify the mono-oxygenase activities tested, whilst the administration of PZQ at a dose of 60 mg/kg/day for 2 days caused a significant decrease in the P450 3A-dependent erythromycin N-demethylase and 6beta testosterone hydroxylase activities. From the incubation of microsomes from lambs not treated with PZQ, a single metabolite (PZQ 11b-OH or PZQ 1-OH) was identified by GC/MS analysis. By selective inhibition of the 3A subfamily performed with triacetyloleandromycin, the production of this metabolite declined by about 90% suggesting a prominent role of P450 3A isoforms in this oxidation. These features indicate that agents or drugs which are able to modulate P450 3A-dependent catalysis may interfere with the metabolism, bioavailability and therapeutic effects of PZQ.  相似文献   

Comparison of three serological tests in the diagnosis of Brucella infection in unvaccinated cattle in Eritrea     

Omer MK  Skjerve E  MacMillan AP  Woldehiwet Z 《Preventive veterinary medicine》2001,48(3):215-222

Three serological methods, the Rose-Bengal test (RBT), the complement-fixation test (CFT) and an indirect enzyme-linked immunosorbent assay (I-ELISA) were compared for the detection of Brucella-infected animals in unvaccinated cattle herds in Eritrea. In this study, 71 herds first were classified as positive or negative for Brucella infection on the basis of at least one animal being seropositive by RBT and CFT. All the 159 RBT-positive samples from the 26 seropositive herds and 214 RBT-negative samples randomly selected from the seropositive herds and from the 45 negative herds were tested further by CFT and I-ELISA. Using the ELISA titer as main predictor, and incorporating the RBT results, a logistic model was built to predict the CFT-negative or -positive status of individual sera and to estimate sensitivity and specificity. Whilst the ELISA titers (< or =20) accurately predicted all the negative sera in herds that were also negative by the CFT, the number of seropositive animals was higher by ELISA in herds that had positive animals. Serum samples which give higher degrees of agglutination with the RBT need not be re-tested with CFT; consideration of the seropositive status of a herd should be taken into consideration on defining the cut-off optical density readings for ELISA.  相似文献   

Effects of low-intensity pulsed ultrasound on wound healing in corneas of dogs following keratoplasty   总被引：1，自引：0，他引：1  

Vicenti FA  Laus JL  Costa Neto JM  Talieri IC  Campos CF  Jorge AT  Ferreira AL  Fantinatti AP 《Veterinary ophthalmology》2003,6(3):255-263

The effects of low-intensity pulsed ultrasound on wound healing were evaluated at the graft-cornea transition in dogs following lamellar keratoplasty using tunica vaginalis preserved in 98% glycerin. Twenty-one dogs were subdivided into three groups of seven animals. The first group (W/US) received daily treatment of low-intensity pulsed ultrasound (20 mW/cm2) for 15 min for the first 10 days post surgery. The second group (N/US) was submitted to the same procedure but with the ultrasound apparatus turned off. The third group, the control (CO), underwent the surgical procedure only. The animals were clinically evaluated during the initial (1-15 days), intermediate (16-30 days) and late (31-120 days) postoperative period. The corneas were evaluated by light microscopy at 1, 3, 7, 15, 30, 60 and 120 days after surgery. Clinically, there were no differences which would promote an advantage to any of the treatments. Light microscopy, however, revealed more extensive vascularization and more advanced wound healing in the W/US group, as well as a tendency towards early graft incorporation. Based on the present results, low-intensity pulsed ultrasound shows advantages, especially in situations where trophic support is a mandatory condition, facilitating better graft incorporation and rapid recovery of stromal organization.  相似文献