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91.
A localised subcutaneous swelling developed on the nasal bridge of a cat receiving chemotherapy for alimentary tract lymphosarcoma. Cytological and histological examination of representative samples of the lesion demonstrated pyogranulomatous inflammation and abundant acid-fast bacilli. A Mycobacterium sp was cultured from tissue excised from the lesion. Extensive testing at three reference laboratories indicated the strain was a member of the Mycobacterium avium complex. The infection was treated successfully by cytoreductive surgery and a 6 weeks course of orally administered clofazimine.  相似文献   
92.
This paper presents an overview of the current status of research on insect neuropeptides. It reviews approaches for identifying insect neuropeptides and their functional roles. It suggests that insect neuropeptide systems can present many potential target sites for the development of novel pesticides.  相似文献   
93.
Electron transmission experiments demonstrate a large asymmetry in the scattering probability of polarized electrons by thin organized films of chiral molecules. This large asymmetry results from the interaction of the electron's wavefunction with many scatterers (molecules) in the organized monolayer structure and represents a manifestation of quantum interference on the scale of supramolecular lengths.  相似文献   
94.
95.
Twenty-three horses with persistent hoof horn defects were treated topically with a hoof disinfectant as part of a hoof care programme for a year. The active ingredients of the disinfectant were a poloaximer-iodine complex, ethylenediamine dihydriodide, isopropyl alcohol and propylene glycol. Hoof trimmings were taken at the start of the study and every six weeks, and examined by scanning and transmission electron microscopy. At the beginning of the study all the horn samples contained large numbers of bacteria, and samples from eight of the horses also had fungal hyphae intermingled with the bacteria. After the application of the hoof disinfectant and adjustments to their diet, there were rapid improvements in the gross appearance of the feet of all the horses; some of them improved within two to three weeks and by 12 weeks the horn quality of all the horses had greatly improved.  相似文献   
96.
Ceftiofur crystalline-free acid sterile suspension (CCFA-SS), a long-acting formulation of ceftiofur formulated for subcutaneous injection in the middle third of the posterior aspect of the ear, is being developed for the control and treatment of bovine respiratory disease. A study was designed to evaluate average daily gain (ADG) and feed efficiency (FE) for cattle through 140 days in the feedlot after CCFA-SS was administered concurrently in the same ear with a growth-promoting implant. On Day 0, steers (n = 207) averaging 189 kg in weight were randomly assigned to the following treatments: Revalor -S implant (120 mg trenbolone acetate and 24 mg estradiol per implant; Hoechst-Roussel Agri-Vet Company) (n = 64); CCFA-SS at 6.6 mg ceftiofur equivalents/kg and a Revalor -S implant (n = 64); untreated control (no CCFA-SS or implant) (n = 63); or CCFA-SS only (n = 16). On Day 56, an Implus-S implant (200 mg progesterone USP plus 20 mg estradiol benzoate; Pharmacia and Upjohn Animal Health) was administered to all cattle. Tolerance of administration of all materials was observed visually and by palpation of the treated ears. Average daily gain and FE from Day 0 through Day 56 were significantly (P <.001) better for steers of both groups with an implanted growth-promotant than for untreated controls. From Day 0 through Day 140, ADG was significantly (P <.05) better for cattle given an implant or an implant plus CCFA-SS than for untreated controls and FE was significantly (P <.05) better for cattle given an implant plus CCFA-SS than for controls. Mild or moderate, transient swelling of the treated ear was observed in two cattle (CCFA-SS plus implant) on Day 52. On Day 56, 88 % of cattle treated with CCFA-SS, 84 % of the cattle treated with an implant plus CCFA-SS, and 100 % of cattle in other groups were normal. Administration of CCFA-SS in the middle third of the posterior aspect of the ear at the same time as growth-promoting implants did not affect performance of cattle in the feedlot and was well tolerated by the animals.  相似文献   
97.
Dentin adhesive restorative techniques are regularly used in veterinary dentistry. Knowledge of the microanatomic structure and properties of dentin is essential to ensure success in restorative procedures. The aim of this study was to describe the density and diameter of dentinal tubules in dog canine teeth using recently described standardized scanning electron microscopy techniques. The results showed dentin of dog canine teeth to be more oval-shaped with a higher tubular density and slightly larger tubular diameters compared with human teeth. These features suggest dog canine teeth have less intertubular dentin compared with human teeth, which may theoretically result in lower resin-dentin shear bond strengths.  相似文献   
98.
After undergoing the processing for electron microscopy, bound uranyl ions are revealed as characteristic electron-opaque crystals. Meristematic walls and associated vesicles become heavily labeled, while pinocytotic accumulation into vacuoles seems probable in cap cells and those just behind the meristem. The endodermal Casparian strip and suberinized lamella are effective barriers to the passage of uranyl ions.  相似文献   
99.
Spinosad is an insect control agent that is derived from a naturally occurring soil bacterium and is effective on several classes of insects, especially Lepidopteran larvae. Spinosad is registered in many countries for use on a variety of crops, including cotton, corn, soybeans, fruits, and vegetables. Residue methods utilizing a magnetic particle-based immunoassay (IA) test kit have been developed and validated for determining spinosad in environmental and food matrices. These methods involve an extraction of the residues from the matrices with appropriate solvents. For some matrices, the sample extracts can be diluted and measured directly by IA without any cleanup. For other matrices, sample extracts are purified using liquid-liquid partitioning and/or solid phase extraction prior to measurement by IA. The methods determine the total residue of spinosad, which includes the active ingredients (spinosyns A and D) and several minor metabolites, including spinosyn B, spinosyn K, and N-demethylspinosyn D. The methods have validated limits of quantitation of 0.0001 microgram/mL in water, 0.05 microgram/g in sediment, and 0.010 microgram/g in crops, crop processed commodities, and animal tissues. This paper briefly summarizes the residue methodology and method validation data for spinosad in 34 food, feed, and environmental matrices.  相似文献   
100.
Doppler velocity observations obtained by the Global Oscillation Network Group (GONG) instruments directly measure the nearly steady flows in the solar photosphere. The sun's differential rotation is accurately determined from single observations. The rotation profile with respect to latitude agrees well with previous measures, but it also shows a slight north-south asymmetry. Rotation profiles averaged over 27-day rotations of the sun reveal the torsional oscillation signal-weak, jetlike features, with amplitudes of 5 meters per second, that are associated with the sunspot latitude activity belts. A meridional circulation with a poleward flow of about 20 meters per second is also evident. Several characteristics of the surface flows suggest the presence of large convection cells.  相似文献   
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