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31.
We hypothesized that long-term loblolly pine (Pinus taeda L.) land-use restores SOC stock and lability of a subtropical Cambisol to the original levels of the natural forest (NF). Additionally, we hypothesized that roots are the major contributor to SOC and that soil stores most of the ecosystem total carbon (ETC). We investigated a chronosequence of loblolly pine land-use of 17 (first rotation) and 32 years (second rotation, unthinned or thinned) following clearing of the NF. The original SOC stock to 100 cm of NF (209?±?9.4 Mg C ha?1) was depleted by 22% after 17 years of pine, possibly because of intense soil disturbance and low quantity and quality of the residue inputted during the pine stand implementation. However, the SOC stock was restored to the original stock of NF after 32 years of pine, with the input of above and belowground biomass at harvest of the first rotation possibly playing a role in this recovery. Thinning did not affect SOC stocks after 1 year. The POM-C reduced after 17 years and was not recovered after 32 years. We could not ascertain in 5-year evaluation whether root or litter was the major contributor to SOC. Soil held 72% of the ETC in NF and 48–59% in pine plantations, confirming that it stores most of the ETC. Overall, long-term loblolly pine land-use seems to restore the original soil carbon stock in this subtropical site, regardless of some lability losses.  相似文献   
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OBJECTIVE: To histologically identify glomerular lesions in dogs infected with Leishmania organisms. ANIMALS: 41 dogs (17 sexually intact males and 14 sexually intact and 10 ovariohysterectomized females) that had positive results when tested for leishmaniosis as determined by use of serologic evaluation (indirect fluorescent antibody test, titers of 1:80 to 1:640) and direct microscopic identification of the protozoal organisms. PROCEDURE: Urine samples were collected by use of cystocentesis and examined by qualitative SDS-agarose gel electrophoresis (AGE). All dogs had non-selective (glomerular) or mixed (glomerular and tubular) proteinemia. Specimens were obtained from each dog during ultrasound-assisted renal biopsy and used for histologic examination. Each specimen was stained with H&E, periodic acid-Schiff, Goldner's trichrome, methenamine silver, and Congo Red stains. Specimens were adequate for evaluation when they contained at least 5 glomeruli/section, except for specimens stained with Congo Red in which 1 glomerulus/section was adequate. RESULTS: Examination of renal biopsy specimens revealed various glomerular lesions in all dogs and interstitial or tubular (or both) lesions in 23 of 41 (55%) dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Glomerular lesions that develop in dogs during infection with Leishmania organisms can be classified histologically as mesangial glomerulonephritis, membranous glomerulonephritis, membranoproliferative glomerulonephritis, and focal segmental glomerulonephritis. Tubulointerstitial histopathologic conditions were not observed as the primary lesion, despite being evident in 23 of 41 (55%) dogs. Use of SDS-AGE for qualitative evaluation of proteinuria and successive collection of specimens during renal biopsies following diagnosis of nonselective glomerular proteinuria provides the possibility for early identification of renal lesions.  相似文献   
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Corynebacterium urealyticum is an uncommon cause of urinary tract infections in cats. However, it is difficult to diagnose and if left untreated it may result in irreversible bladder lesions. C urealyticum is a multiantibiotic-resistant bacterium whose culture requires special care. Risk factors for the occurrence of this infection include urological procedures, foreign bodies, bladder mucosa abnormalities, immuno-suppressed states and antibiotic treatment. This report describes an unusual case of C urealyticum urinary infection in a young cat with pre-existing urethral obstruction. C urealyticum was isolated in pure cultures from two urine samples. Clinical and ultrasound features, results of the urinalysis and urine culture are described as well as therapeutic treatment and eventual favourable outcome to treatment with amoxycillin-clavulanic acid.  相似文献   
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BACKGROUND: There are few studies evaluating the natural history and prognostic variables in chronic mitral valve disease (CMVI) in a heterogeneous population of dogs. OBJECTIVES: To estimate survival and prognostic value of clinical and echocardiographic variables in dogs with CMVI of varying severity. Five hundred and fifty-eight dogs belonging to 36 breeds were studied. METHODS: Dogs were included after clinical examination and echocardiography. Long-term outcome was assessed by telephone interview with the owner. RESULTS: The mean follow-up time was 22.7 +/- 13.6 months, and the median survival time was 19.5 +/- 13.2 months. In univariate analysis, age>8 years, syncope, HR>140 bpm, dyspnea, arrhythmias, class of heart failure (International Small Animal Cardiac Health Council), furosemide therapy, end-systolic volume-index (ESV-I)>30 mL/m(2), left atrial to aortic root ratio (LA/Ao)>1.7, E wave transmitral peak velocity (Emax)>1.2 m/s, and bilateral mitral valve leaflet engagement were associated with survival time when all causes of death were included. For the cardiac-related deaths, all the previous variables except dyspnea and EDV-I>100 mL/m(2) were significantly associated with survival time. Significant variables in multivariate analysis (all causes of death) were syncope, LA/Ao>1.7 m/s, and Emax>1.2 m/s. For cardiac-related death, the only significant variable was LA/Ao>1.7. CONCLUSIONS AND CLINICAL IMPORTANCE: Mild CMVI is a relatively benign condition in dogs. However, some clinical variables can identify dogs at a higher risk of death; these variables might be useful to identify individuals that need more frequent monitoring or therapeutic intervention.  相似文献   
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Serum catecholamine levels and myocardial and lymphocyte adrenergic receptor (AR) concentrations were measured in adult great danes affected by canine dilated cardiomyopathy (DCM) and compared to those of healthy animals. A non-homogeneous population of beta -AR, consisting of beta(1)-AR and beta(2)-AR, was observed in healthy (41 and 59%, respectively) and affected (17 and 83%, respectively) dog lymphocytes. Binding assays revealed that total beta -AR, beta(1)-AR and alpha(1)-AR were significantly downregulated (P<0.05;P<0.01;P<0. 001), both in lymphocyte and myocardial cell membranes of affected dogs. beta(2)-Adrenergic receptor concentrations were significantly reduced only in lymphocyte and right atrium cell membranes (P<0.05). Downregulation was not associated with alterations in receptor binding characteristics, as no significant differences in K(d)values were found. Mean plasma catecholamine levels were significantly higher (P<0.01) in DCM dogs (939+/-41) than in normal subjects (348+/-32), thus suggesting a sympathetic activation. The present study indicates a condition similar to that observed in human patients affected by DCM and that adrenergic receptors in canine lymphocytes reflect the fluctuation of adrenergic receptor concentrations in the myocardium.  相似文献   
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Ultrasonographic evaluation of the adrenal glands was performed in 85 dogs, followed by macroscopic and histopathological examination either post‐mortem or after adrenalectomy. This retrospective cross‐sectional study evaluated the difference between gross and ultrasonographic measurements to determine the diagnostic accuracy of ultrasonography in the evaluation of canine adrenal gland size. The differences were assessed for gland length, thickness at cranial, middle and caudal regions, and surface area. In our sample, ultrasound error accuracy ranged between 0% in measurement of the right adrenal gland surface area and 25.21% for left cranial pole thickness. The parameters with minor errors were caudal pole thickness (3.64% right side and 3.49% left side) and length (5.75% right side and 2.19% left side). The ultrasonographic measurements generally underestimated the actual size of the adrenal glands. No statistically significant differences were observed for measurement errors between normal and pathological adrenal glands. This study confirmed that the caudal pole of both glands is the best parameter for ultrasonographic evaluation of normal and pathological adrenal glands size in dog. Furthermore, the surface area could be considered as a dimensional parameter for better assessment of the complex shape and the global aspect of the adrenal glands, while standardize ultrasonographic projections are needed to measure the cranial pole of both adrenal glands.  相似文献   
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