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71.
72.
Feline vaccine-associated sarcomas have presented many challenges. Initially, the etiopathogenesis and biological behavior of these tumors had to be characterized, and strategies implemented to move tumors away from problematic sites. Next, diagnostic and treatment recommendations evolved as the biologic behavior of vaccine-associated sarcomas forced early and aggressive intervention. Current therapeutic strategies are expensive, at times debilitating, and frequently fail to effect tumor control. This review summarizes the known history, epidemiology, etiology, and clinical management of vaccine-associated sarcomas after a decade of work. The next challenges must be to find more practical and effective solutions, and to eliminate the cause of vaccine-associated sarcomas.  相似文献   
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The objective of this study was to evaluate bull sperm kinematics after centrifugation through a single layer of a colloid [Single Layer Centrifugation (SLC)]. Ejaculates from 20 bulls were extended and stored at 4–6°C for 24 h during transport to the laboratory for SLC through Androcoll‐B, followed by measurement of sperm kinematics in all samples. Total motility (86% and 88% for uncentrifuged and SLC samples, respectively) and progressive motility (84% for both the groups) were similar (p > 0.05). In contrast, straightness (STR) (0.65 vs 0.69), linearity (LIN) (0.32 vs 0.35) and beat cross frequency (BCF) (22.3 vs 23.6 Hz) were significantly higher in the SLC‐selected samples than in the uncentrifuged samples, whereas velocity of the average path (VAP) (95 vs 90 μm/s), curvilinear velocity (VCL) (192 vs 180 μm/s), amplitude of lateral head deviation (ALH) (7 μm vs 6.5 μm) and hypermotility (49% vs 38%) were significantly decreased. The kinematics of the samples with the poorest motility was improved most by SLC. In conclusion, even though SLC had no direct effect on total and progressive motility, it appeared to have a positive influence on several other kinematic parameters that may be important for fertilization after artificial insemination.  相似文献   
75.
Two cumulene carbenes, H2C5 and H2C6, were detected in a supersonic molecular beam by Fourier transform microwave spectroscopy. Their rotational and leading centrifugal distortion constants were determined with high accuracy, such that the entire radio spectrum can now be calculated. Like the known carbenes H2C3 and H2C4, both molecules have singlet electronic ground states and linear carbon-chain backbones. They can be produced in sufficiently high concentrations in the laboratory that their electronic spectra, expected to lie in the visible, should be readily detectable by laser spectroscopy. The microwave spectra of other, more exotic isomers may be detectable as well.  相似文献   
76.
Laser Rapid Prototyping of Photonic Band-Gap Microstructures   总被引:1,自引:0,他引:1  
Three-dimensional periodic microstructures of aluminum oxide, which are important for creating photonic band-gap structures (PBGs), were fabricated by laser rapid prototyping by means of laser-induced direct-write deposition from the gas phase. The structures consisted of layers of parallel rods forming a face-centered tetragonal lattice with lattice constants of 66 and 133 micrometers. These structures showed transmission minima centered around 4 terahertz (75 micrometers) and 2 terahertz (150 micrometers), respectively. PBGs will allow precise control of the optical properties of materials, including lasers without threshold.  相似文献   
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Orbital plasmacytoma in a cat   总被引:1,自引:0,他引:1  
An Abyssinian cat presented with epistaxis, melaena and retinal vascular changes. Plasma protein levels were markedly elevated and a monoclonal gammopathy was present on serum protein electrophoresis. Based on these laboratory findings, hyperviscosity syndrome was assumed to be responsible for the clinical signs. The cat responded initially to fluid therapy, but relapsed and then developed unilateral exophthalmia. The animal was euthanased and an extramedullar plasmacytoma of the right orbit was diagnosed at postmortem examination.  相似文献   
79.
Radiolabeled gold colloid (198Au), which has been used to assess particle clearance in mammalian species, was used to assess blood-borne particle clearance in turkeys. When turkeys 16 weeks of age were injected intravenously with these particles, there was greater than a 98% decrease in blood gamma emission from 1 minute to 6 minutes postinjection. Uptake of particles was predominantly hepatic with minor uptake by the spleen and bone marrow. Negligible uptake was observed in lung, kidney, and skeletal muscle. Autoradiography demonstrated particles within Kupffer cells of the liver, periarteriolar macrophages of the spleen, and bone-marrow macrophages. Particles could not be demonstrated within the lung or kidney. The mononuclear phagocyte system responsible for blood particle clearance in turkeys is therefore located predominantly within the liver, spleen, and bone marrow and is similar to that of rats, mice, rabbits, and dogs. Pulmonary intravascular macrophages, which have recently been described in ruminants and pigs, are not apparent in this species.  相似文献   
80.
A cutaneous mass (1.5 cm in diameter) was removed from the head of a horse and was diagnosed histologically as eumycotic mycetoma. Immunofluorescence, performed on formalin-fixed, paraffin-embedded tissue, identified Pseudallescheria boydii as the etiologic agent. Findings from earlier reports of eumycotic mycetoma were compared with those of this horse.  相似文献   
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