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71.
72.
Aural plaques affect at least 22% of horses and can be asymptomatic or cause ear sensitivity. Immunohistochemical and electron microscopy studies have shown a strong association between aural plaques and papilloma virus. The purpose of this study was to investigate the efficacy of imiquimod 5% cream, an immune response modifier with potent antiviral activity, in the treatment of equine aural plaques. Twenty‐one horses were enrolled and 16 completed the study. Imiquimod 5% cream was applied three times a week, every other week. When both ears were affected only the worst affected ear was treated. Adverse effects in all horses included marked local inflammation, exudation and thick crust formation at the site of treatment and the adjacent skin. Removal of the crust before treatment was painful and required sedation in most horses. Complete resolution of lesions was noted in all horses immediately post‐treatment and the long‐term resolution rate was 87.5%. Duration of therapy ranged from 1.5 to 8 months (median: 2.9 mean: 3.5). All horses were followed‐up for 12–22 months after treatment was discontinued and only two horses had a recurrence of lesions. Clinical signs related to the aural plaques prior to treatment were reported in 11 of 16 (68.8%) horses and included resistance to touching the ears and bridling. Complete resolution of these signs was reported by the owners in all of the horses followed‐up for at least 12 months. In conclusion, the topical application of imiquimod 5% cream is an efficacious treatment for aural plaques in horses.  相似文献   
73.
Safety and efficacy of a protocol of alternating 1‐(2‐chloroethyl)‐3‐cyclohexyl‐1‐nitrosourea (CCNU; 70 mg m?2) and vinblastine (3.5 mg m?2), and prednisone (1–2 mg kg?1; CVP) in dogs with mast cell tumours (MCT) were evaluated. A total of 17 dogs had nonresectable MCTs and 35 received CVP as adjunctive treatment to locoregional control of metastatic MCTs or grade III MCTs. Neutropenia with fever occurred in 8% of dogs after treatment with vinblastine and in 2% after treatment with CCNU. Persistent elevation of serum alanine transaminase, suggestive of hepatotoxicity, occurred in 9% of the dogs. Response rate in dogs with nonresectable MCTs was 65%; five achieved a complete response (median, 141 days) and six achieved a partial response (median, 66 days). Overall median progression‐free survival (PFS) time in dogs treated in the adjuvant setting was 489 days. Dogs with grade III MCTs had shorter PFS compared with dogs with metastatic grade II MCTs (190 days versus 954 days; P < 0.001). Phase III studies are needed to provide reliable information about the comparative efficacy of this protocol.  相似文献   
74.
Seafloor diking-eruptive events represent the irreducible, quantum events of upper oceanic crustal accretion. They record events by which a large portion of the oceanic crust has formed through geological history. Since 1993, the U.S. Navy's real-time Sound Surveillance System has allowed location of ongoing acoustic signatures of dike emplacement and basalt eruptions at ridge crests in the northeast Pacific. These diking-eruptive events trigger a sequence of related, rapidly evolving physical, chemical, and biological processes. Magmatic volatiles released during these events may provide nutrients for communities of subseafloor microorganisms, some of which thrive in high-temperature anaerobic environments. Many of the organisms identified from these systems are Archaea. If microorganisms can thrive in the water-saturated pores and cracks within deep, volcanically active portions of our planet, other hydrothermally active planets may harbor similar life forms.  相似文献   
75.
The Mars Global Surveyor (MGS) z-axis accelerometer has obtained over 200 vertical structures of thermospheric density, temperature, and pressure, ranging from 110 to 170 kilometers, compared to only three previous such vertical structures. In November 1997, a regional dust storm in the Southern Hemisphere triggered an unexpectedly large thermospheric response at mid-northern latitudes, increasing the altitude of thermospheric pressure surfaces there by as much as 8 kilometers and indicating a strong global thermospheric response to a regional dust storm. Throughout the MGS mission, thermospheric density bulges have been detected on opposite sides of the planet near 90 degreesE and 90 degreesW, in the vicinity of maximum terrain heights. This wave 2 pattern may be caused by topographically-forced planetary waves propagating up from the lower atmosphere.  相似文献   
76.
Thoroughly tested simulation models are needed to help quantify the long-term effects of agriculture. We evaluated the Root Zone Water Quality Model (RZWQM) response to different N management strategies and then used the tested model with observed weather data from 1961-2003 to quantify long-term effects on corn (Zea mays L.) yield and flow weighted nitrate-N concentration in subsurface “tile” drainage water (Nconc). Fourteen years (1990-2003) of field data from 30, 0.4 ha plots in northeast Iowa were available for model testing. Annual crop yield, nitrate-N loss to subsurface “tile” drainage water (Nloss), Nconc, and subsurface “tile” drainage amount (drain) for various management scenarios were averaged over plots and years to create five chemical fertilizer and five swine manure treatments. Predicted corn yield and Nconc for the 10 treatments were significantly correlated with observed data (R2 > 0.83). The Root Mean Square Errors (RMSE) were 15% and 18% of its observed average Nconc for chemical fertilizer and manure treatments, respectively. Corresponding RMSEs for corn yields were 8% and 10% of its observed average corn yields for chemical fertilizer and manure treatments. The long-term simulations indicate that average corn yield plateaus and Nloss accelerates as quadratic functions of increasing spring UAN-N rates from 100 to 200 kg N/ha. Winter wheat (Triticum aestivum L.) sowed after corn and soybean [Glycine max (L.) Merr.] harvest was predicted to reduce long-term Nloss by 5 to 6 kg N/ha, which appears consistent with published field studies and may be a treatment to ameliorate agricultural management with potential for elevated Nloss such as swine manure application to soybean. The results suggest that after calibration and thorough testing, RZWQM can be used to quantify the relative effects of corn production and Nconc under several alternative management practices.  相似文献   
77.
Streptococcus suis serotypes associated with disease in weaned pigs   总被引:5,自引:0,他引:5  
Streptococcus suis was recovered from 9 outbreaks of septicaemia and meningitis in weaned pigs between 1979 and 1983. Fifteen isolates from 7 outbreaks were identified as S. suis type 9, and 3 isolates from 2 outbreaks as S. suis type 2. Three further isolates of S. suis type 2 and an isolate of S. suis type 3 were recovered from cases of bronchopneumonia in weaned pigs from 4 other piggeries.  相似文献   
78.
Choice of an analgesic for gastrointestinal pain requires consideration of the cause of the pain, desired duration of pain relief, need for sedation, and potential side effects and toxicity, particularly in light of other drugs being used and effects on the gastrointestinal tract. It is imperative that close monitoring be continued to ensure that surgical lesions or worsening conditions are detected. Recent research in the field may lead to new drugs, drug combinations, and avenues of treatment that minimize the side effects of these drugs while maximizing their efficacy.  相似文献   
79.
SUMMARY The epidemiological, clinical and pathological features of a disease syndrome in adult cattle grazing woolly-pod vetch (Vicia villosa ssp dasycarpa) or popany vetch (V benghalensis) are reported. Outbreaks of toxlcosis occurred between midwinter and midsummer in 3 dairy and 6 beef herds on the north coast of New South Wales, between 1982 and 1992. Friesian, Angus, Murray Grey, Guernsey and Hereford breeds were affected. Mean morbidity and case fatality rates in affected herds were 7% (65 of 889) and 69%, respectively. Signs of pruritic dermatitis, illthrift and death were associated with an eosinophilic granulomatous inflammation of many organs, particularly involving the renal cortex, dermis, myocardium, adrenal glands, lymph nodes and hepatic portal triads.  相似文献   
80.
Endoscopic tracheal lavage cytology was evaluated before and 24 hours after standing transendoscopic laser surgery of the upper airway in 18 horses (9 patients undergoing Neodymium:yttrium aluminum garnet [Nd:YAG] surgery and 9 non-patient horses undergoing argon surgery). Paired endoscopic tracheal lavages taken 24 hours apart were evaluated in six control horses to determine if the lavage technique influenced the cytology. After 24 hours, no inflammation was noted in three, mild inflammation was noted in six and suppurative inflammation in four surgically treated horses. Five of the surgically treated horses underwent general anesthesia prior to baseline tracheal lavage and had evidence of inflammation in pre-laser lavage samples; this made it difficult to assess the true incidence of laser-induced inflammation in horses in this report. Five of six control horses had a normal tracheal lavage at 24 hours. Six normal adult horses had baseline tracheal mucous clearance rates determined using scintigraphy followed one week later by tracheal mucous clearance rates two hours after either standing transendoscopic Nd:YAG ventriculectomy or standing transendoscopic argon cauterization of a 2 × 2 cm area of dorsal pharynx. The horses were left in pasture for three weeks, followed by a second baseline and post-laser tracheal mucous clearance rate using the opposite laser technique. There was no significant difference between the first and second baseline measurements. The order of laser treatments had no effect on the results obtained. There was no significant difference between the baseline tracheal mucous clearance rates (mean 1.65 ± 0.65 cm/min) and tracheal mucous clearance rates post-laser surgery (mean 1.62 ± 1.21 cm/min). Neither laser technique altered tracheal mucous clearance rates significantly (argon mean 1.57 ± 0.59 cm/min and Nd:YAG mean 1.67 ± .68 cm/min.  相似文献   
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