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1.
A ranch in central South Dakota had a number of dead calves because of arsenic poisoning. The clinical picture included diarrhea, central nervous system signs, and death. Gross necropsy findings included adequate body fat, stomachs full of normal-appearing ingesta, and large amounts of greenish brown watery fluid in the intestine and colon. Microscopically there was severe lymphoid tissue necrosis in the mesenteric lymph nodes and gut-associated lymphoid tissue. Chemical analysis of kidneys showed no significant amounts of lead; however, kidney arsenic concentrations were 25 to 44 ppm. The source was a small pile of Paris Green (common name for cupric acetoarsenite) found in an old dump site in the pasture.  相似文献   
2.
Canine juvenile-onset insulin-dependent diabetes mellitus is a rare disease. While pancreatic acinar atrophy is a well known picture in the dog, the simultaneous occurrence with an endocrine insufficiency has never been clearly established. The clinical, pathological and immunohistochemical findings of a three-month-old German shepherd dog with insulin-dependent diabetes mellitus concurrent with exocrine pancreatic insufficiency are described.  相似文献   
3.
OBJECTIVE: To investigate whether volumetric capnography indices could be used to differentiate between horses without recurrent airway obstruction (RAO) and horses with RAO that were in clinical remission or that had clinically apparent RAO. ANIMALS: 70 adult Swiss Warmblood horses (20 used for pleasure riding and 50 used for dressage or show jumping). PROCEDURE: Horses were allocated to 4 groups on the basis of history, clinical signs, results of endoscopy, and cytologic findings (group 1, 21 healthy horses; group 2, 22 horses with RAO that were in remission; group 3, 16 horses with mild RAO; group 4, 11 horses with exacerbated RAO). Expiratory volume and CO2 curves were recorded by use of a computerized ultrasonic spirometer. Volumetric capnograms were plotted, and derived indices were calculated. RESULTS: Dead-space volume (VD) was calculated by use of the Bohr equation (VD(Bohr)) and for physiologic VD (VD(phys)). Ratios for VD(Bohr) to expiratory tidal volume (VT) and VD(phys) to V(T) as well as an index of effective CO2 elimination were significantly different among groups of horses. Age and use of the horses also significantly affected volumetric capnography indices. CONCLUSIONS AND CLINICAL RELEVANCE: Ratios of VD(Bohr) to VT and VD(phys) to VT as well as an index of effective CO2 elimination were sufficiently sensitive measures to distinguish between healthy horses and horses with RAO in remission. To optimize the ability of volumetric capnography indices to differentiate among horses in heterogeneous populations, it is important to account for effects of age and specific use of the horses.  相似文献   
4.
The efficacy of trilostane in the treatment of canine pituitary-dependent hyperadrenocorticism (PDH) was evaluated in 78 dogs with the condition which were treated for up to three years. The drug appeared to be well tolerated by almost all the dogs, and only two developed clinical signs and biochemical evidence of hypoadrenocorticism. Polyuria and polydipsia completely resolved in 70 per cent of the dogs that had these problems, and skin changes resolved in 62 per cent of the dogs that had skin abnormalities. There was a significant reduction (P<0.001 in each case) in both the mean basal and post-adrenocorticotrophic hormone (ACTH) cortisol concentrations after a mean of 12.3 days of treatment. The post-ACTH cortisol concentration decreased to less than 250 nmol/litre in 81 per cent of the dogs within one month of the start of treatment and in another 15 per cent at some later time. The median survival time of the 26 dogs which died was 549 days, and 51 of the dogs were alive at the completion of the study. One was lost to follow up after 241 days treatment.  相似文献   
5.
The discovery of the spiral bacterium Helicobacter pylori and its causative role in gastric disease in humans has brought a dramatic change to gastroenterology. Although spiral bacteria have been known for more than a century to infect the stomachs of dogs and cats, recent research has been conducted mainly in the wake of interest in H. pylori. H. pylori has not been found in dogs and only very rarely in cats and zoonotic risk is minimal. A variety of other Helicobacter spp. can infect the stomach of pets; however, their pathogenic role is far from clear, and they have a small but real zoonotic potential. The prevalence of gastric Helicobacter spp. in dogs and cats is high, irrespective of clinical signs, and as in human medicine, mode of transmission is unclear. The relationship of Helicobacter spp. to gastric inflammation in cats and dogs is unresolved, with inflammation, glandular degeneration, and lymphoid follicle hyperplasia accompanying infection in some but not all subjects. Circulating anti-Helicobacter immunoglobulin G antibodies have been detected in 80% of dogs with naturally acquired infection and most dogs and cats with experimental infection. The gastric secretory axis is similar in infected and uninfected cats and dogs and no relationship of infection to gastrointestinal ulcers has been found. Differences in the pathogenicity of Helicobacter spp. are apparent, because infection with H pylori is associated with a more severe gastritis than infection with other Helicobacter spp. in both cats and dogs. Rapid urease test, histopathology, and touch cytology are all highly accurate invasive diagnostic tests for gastric Helicobacter-like organisms in dogs and cats, whereas culture and polymerase chain reaction are the only means to identify them to the species level. Urea breath and blood tests or serology can be used to diagnose Helicobacter spp. noninvasively in dogs and cats. Most therapeutic studies in pets have not shown long-term eradication of Helicobacter spp. Whether this is due to reinfection or recrudescence has not been established.  相似文献   
6.
7.
To evaluate the potential benefits and risks associated with tea consumption it is important to identify the constituents of this beverage. Levels of some minerals, caffeine and catechins in green tea samples commercialized in Portugal were evaluated. Potassium is the metal present in larger amount (92–151 mg/l). The content of sodium, calcium, fluoride, aluminium, manganese and iron were 35–69, 1.9–3.5, 0.80–2.0, 1.0–2.2, 0.52–1.9, 0.020–0.128 mg/l, respectively. Chromium and selenium were not detected. The resulting data showed considerable variability in catechins content. The levels of epigallocatechin gallate (EGCG) ranged from 117 to 442 mg/l, epicatechin 3-gallate (EGC) from 203 to 471 mg/l, epigallocatechin (ECG) from 16.9 to 150 mg/l, epicatechin (EC) from 25 to 81 mg/l and catechin (C) from 9.03 to 115 mg/l. Caffeine contents in the green tea infusions studied were between 141–338 mg/l. Green tea infusions provide significant amounts of catechins and could be an important source of some minerals.  相似文献   
8.

Background

Neutrophil gelatinase–associated lipocalin (NGAL) is a protein that is used in human medicine as a real‐time indicator of acute kidney injury (AKI).

Hypothesis

Dogs with AKI have significantly higher plasma NGAL concentration and urine NGAL‐to‐creatinine ratio (UNCR) compared with healthy dogs and dogs with chronic kidney disease (CKD).

Animals

18 healthy control dogs, 17 dogs with CKD, and 48 dogs with AKI.

Methods

Over a period of 1 year, all dogs with renal azotemia were prospectively included. Urine and plasma samples were collected during the first 24 hours after presentation or after development of renal azotemia. Plasma and urine NGAL concentrations were measured with a commercially available canine NGAL Elisa Kit (Bioporto® Diagnostic) and UNCR was calculated. A single‐injection plasma inulin clearance was performed in the healthy dogs.

Results

Median (range) NGAL plasma concentration in healthy dogs, dogs with CKD, and AKI were 10.7 ng/mL (2.5–21.2), 22.0 ng/mL (7.7–62.3), and 48.3 ng/mL (5.7–469.0), respectively. UNCR was 2 × 10−8 (0–46), 1,424 × 10−8 (385–18,347), and 2,366 × 10−8 (36–994,669), respectively. Dogs with renal azotemia had significantly higher NGAL concentrations and UNCR than did healthy dogs (P < .0001 for both). Plasma NGAL concentration was significantly higher in dogs with AKI compared with dogs with CKD (P = .027).

Conclusions and Clinical Importance

Plasma NGAL could be helpful to differentiate AKI from CKD in dogs with renal azotemia.  相似文献   
9.
Trilostane, a 3beta-hydroxysteroid dehydrogenase inhibitor, has been used successfully over the last few years for the treatment of canine pituitary-dependent hyperadrenocorticism. In a prospective study of 19 dogs with pituitary-dependent hyperadrenocorticism, the adrenal glands were measured before and at least 6 months after initiation of trilostane therapy. Right adrenal gland length and caudal pole thickness and left adrenal gland caudal pole thickness increased significantly (p < or = 0.05); there was no significant change in left adrenal gland length. Enlargement of adrenal glands during trilostane therapy may occur as a result of suppression of the negative feedback mechanism affecting cortisol production.  相似文献   
10.
The chlorophyll fluorescence kinetics of ‘Jonagold’ and ‘Cox’ apples, stored under different conditions to induce mealiness, were measured. Three different storage conditions were considered causing three mealiness levels: not mealy, moderately and strongly mealy. Also destructive measurements of the texture (firmness, hardness, juice content and soluble solids content) were done. Classification into different mealiness levels based on the fluorescence measurements was more performant than a classification based on the destructive measurements. To estimate the mealiness level in a non-destructive way from the fluorescence features, a number of different classifiers were constructed. Quadratic discriminants and supervised and unsupervised neural networks were tested and compared. The self-organising map gives promising results when compared with the multi-layer perceptrons and quadratic discriminant analysis. The different advantages of the constructed classifiers suggest that fluorescence can be used in an automatic sorting line to assess certain types of mealiness.  相似文献   
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