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Using data from the National Conference of State Legislatures, this paper examines the state budget stabilization funds of Indiana, Iowa, Missouri, Michigan, Minnesota, Ohio, and Wisconsin. Unlike previous research, this paper examines the movement of the fund balances over time (between 1983 and 1991), to see how the fund balances move in relation to a number of indicators of state fiscal health. The results of this research show that the use of these funds varies significantly among the states as does the level of funding and therefore the ability of the funds to serve as an effective tool for counter-cyclical state fiscal policy.  相似文献   
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We describe the computed tomography (CT) findings in 11 dogs with middle ear cholesteatoma. The cholesteatoma appeared as an expansile tympanic cavity mass with a mean attenuation value of 55.8±4.2 Hounsfield units. There was no appreciable contrast enhancement of the tympanic bulla contense but ring enhancement was seen in four dogs. Due to the slow progressive growth, the lesion causes severe bone changes at the contour of the tympanic bulla, including osteolysis, osteoproliferation and osteosclerosis, expansion of the tympanic cavity, and sclerosis or osteoproliferation of the ipsilateral temporomandibular joint and paracondylar process. Cholesteatoma can cause lysis of the petrosal part of the temporal bone, leading to intracranial complications. Although not definitive, CT provides useful information for distinguishing a middle ear cholesteatoma from otitis media and neoplasia. In otitis media, enlargement of the tympanic cavity is not routinely observed. In tumors that primarily affect the middle or inner ear, the predominant signs are lysis of the contour of the tympanic bulla or the petrosal part of the temporal bone, soft tissue swelling around the middle ear and marked contrast enhancement. In tumors that arise from the external ear, a soft tissue mass is visible within the external acusticus meatus, and the middle ear is only involved secondarily.  相似文献   
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We studied the sorption of phosphate and oxalate on a synthetic aluminium hydroxysulphate complex and the associated release of sulphate from this complex. In the pH range 4.0–9.0 the presence of phosphate or oxalate tended to increase the release of sulphate. Much more phosphate than oxalate was sorbed, but in most cases oxalate caused more removal of sulphate than did phosphate. Only in acid systems may these results be partly attributed to the greater solubilization of the complex in the presence of oxalate than in the presence of phosphate. At pH > 8.0 in the presence of phosphate, and at pH > 6.5 in the presence of oxalate, the quantities of sulphate replaced were greater than the quantities of phosphate or oxalate sorbed, suggesting that hydroxyl ions competed with phosphate and oxalate for sorption sites and sulphate removal. Sulphate was only partly removed from the complex even after repeated washings with phosphate or oxalate solutions or after 120 h in the presence of these ligands at pH 6.0. When phosphate and oxalate were added as a mixture much more phosphate than oxalate was retained. Phosphate strongly inhibited oxalate sorption, whereas oxalate partly prevented phosphate sorption only at pH < 7.0. More sulphate was removed in the presence of both the anions than in the presence of phosphate alone, but less than that desorbed in the presence of oxalate alone.  相似文献   
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In this work we investigated which mitral valve leaflet was most often involved in mitral valve prolapse with degenerative mitral valve disease and whether there was an association with breed, age, gender, or weight. Five hundred and thirty-seven dogs with mitral valve prolapse-degenerative mitral valve disease were assessed; the cross-breed dog was the most represented breed (248 dogs, 46.2%). Mitral valve prolapse was more common in male dogs, and the average age was 11.3±2.8 years. Prolapse of the anterior leaflet was present in 48.4% of dogs, prolapse of the the posterior leaflet in 7.1%, and bileaflet prolapse was present in 44.5%; this distribution is different than that typically found in humans. There was a significant correlation between severity of mitral regurgitation and severity of mitral valve prolapse or ISACHC class, and between severity of mitral valve prolapse and ISACHC class. There was no relationship between the particular affected leaflet(s) and severity of mitral regurgitation, severity of mitral valve prolapse, or ISACHC class. Our findings suggest that the susceptibility to the mitral valve prolapse-degenerative mitral valve disease is not confined to a specific breeds and that the specific leaflet prolapsing is different in dogs compared with humans.  相似文献   
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While skin sparing is an advantage of megavoltage beams, in certain clinical situations the planning target volume includes the skin surface and a skin sparing effect is not desirable. A tissue equivalent material, termed build up bolus, is used in these situations to provide adequate absorbed dose at the surface of the skin. However, an irregular patient contour can lead to air gaps between the build up bolus and the skin surface, which may result in variability in radiation dose across the target volume. The shape of the canine distal hind extremity is irregular, and commercially available bolus materials do not conform well to this region. The purpose of this study was to assess the dose homogeneity achieved using a petroleum-based bolus material, in combination with a commercially available sheet bolus, for radiation treatment of the canine tarsus. Repeated setups were performed to mimic daily treatment setups in the clinic setting, and computed tomographic scans were performed after each setup. Dose distribution achieved with a cobalt therapy machine and a 6 MV linear accelerator was assessed using three-dimensional treatment planning software. The dose to the clinical target volume fell within 95% and 107% of the prescribed dose for both treatment machines, which is considered clinically acceptable by the authors. This petroleum-based bolus is equivalent to water in its photon attenuation, conforms well to an irregular patient contour, and retains its shape after positioning. Applications to other anatomical sites could be considered.  相似文献   
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Objective— To develop an in vitro laryngeal model to mimic airflow and pressures experienced by horses at maximal exercise with which to test laryngoplasty techniques.
Study Design— Randomized complete block.
Sample Population— Cadaveric equine larynges (n=10).
Methods— Equine larynges were collected at necropsy and a bilateral prosthetic laryngoplasty suture was placed with #5 Fiberwire suture to achieve bilateral maximal arytenoid abduction. Each larynx was positioned in a flow chamber and subjected to static flow and dynamic flow cycling at 2 Hz. Tracheal pressure and flow, and pressure within the flow chamber were recorded at a sampling frequency of 500 Hz. Data obtained were compared with the published physiologic values for horses exercising at maximal exercise.
Results— Under static flow conditions, the testing system produced inspiratory tracheal pressures (mean±SEM) of −33.0±0.98 mm Hg at a flow of 54.48±1.8 L/s. Pressure in the flow chamber was −8.1±2.2 mm Hg producing a translaryngeal impedance of 0.56±0.15 mm Hg/L/s. Under dynamic conditions, cycling flow and pressure were reproduced at a frequency of 2 Hz, the peak inspiratory (mean±SEM) pharyngeal and tracheal pressures across all larynges were −8.85±2.5 and −35.54±1.6 mm Hg, respectively. Peak inspiratory flow was 51.65±2.3 L/s and impedance was 0.57±0.06 mm Hg/L/s.
Conclusions— The model produced inspiratory pressures similar to those in horses at maximal exercise when airflows experienced at exercise were used.
Clinical Relevance— This model will allow testing of multiple novel techniques and may facilitate development of improved techniques for prosthetic laryngoplasty.  相似文献   
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