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101.
Funaba M Yamate T Hashida Y Maki K Gotoh K Kaneko M Yamamoto H Iriki T Hatano Y Abe M 《American journal of veterinary research》2003,64(8):1059-1064
OBJECTIVE: To evaluate the effects of a high-protein diet versus dietary supplementation with ammonium chloride (NH4Cl) on struvite crystal formation in the urine of clinically normal cats by measuring the urine concentration of hydrochloric acid (HCl)-insoluble sediment, urine pH, struvite activity product (SAP), number of struvite crystals in urine, and urine volume. ANIMALS: 23 healthy adult cats. PROCEDURE: Urine was fractionated by centrifugation with subsequent extraction of the sediment with 1 N HCl (study 1). Diets containing either 29% crude protein or 55% crude protein were fed to cats in a crossover trial of 3 weeks/period (study 2). Diets supplemented with either sodium chloride (NaCl) or NH4Cl were fed, by use of a 3 x 3 Latin-square design with 3 wk/period (study 3). In studies 2 and 3, urine samples were collected for the last 7 days of each period. RESULTS: The HCl-insoluble sediment contained Tamm-Horsfall glycoprotein (THP; study 1). The high-protein diet (study 2) and dietary supplementation with NH4Cl (study 3) resulted in a decrease in urine pH, SAP, and the number of struvite crystals in urine. However, the high-protein diet decreased urine concentrations of HCl-insoluble sediment containing THP (study 2), in contrast to the NH4Cl supplementation that increased urine volume without a significant effect on the urine concentration of the HCl-insoluble sediment (study 3). CONCLUSIONS AND CLINICAL RELEVANCE: Our results indicate that compared with dietary supplementation with NH4Cl, the high-protein diet is preferable as a urine acidifier for the prevention of struvite crystal formation in clinically normal cats. 相似文献
102.
Hepatocyte growth factor transduces different intracellular signals in aortic and umbilical venous endothelial cells 总被引:1,自引:0,他引:1
Makondo K Kimura K Kitamura T Yamaji D Saito M 《The Japanese journal of veterinary research》2003,51(2):105-112
Endothelial cells are important for maintenance of vascular integrity by producing a variety of bioactive molecules such as nitric oxide (NO). Recent evidence has suggested that there are some differences in characteristics between endothelial cells from different origins. Here we examined responses of two typical endothelial cells to hepatocyte growth factor (HGF), which induces endothelium-dependent relaxation of microvessels. Stimulation of human umbilical vein endothelial cells (HUVEC) and bovine aortic endothelial cells (BAEC) with HGF increased endothelial NO synthase activity, accompanied with an increase of activity-related site-specific phosphorylation of protein kinase B/Akt. However, HGF stimulated phosphorylation of p38 mitogen-activated protein kinase (MAPK) only in HUVEC, but not in BAEC, while it induced phosphorylation of p44/p42 MAPK in both cells. These results suggest that HGF transduces different intracellular signals between aortic and umbilical venous endothelial cells, and that the differences might represent divergent endothelial responses to growth factors, especially those that activate receptor-tyrosine kinases. 相似文献
103.
104.
105.
Saito K Nakanishi M Hasegawa A 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(6):495-497
The type, ages of occurrence, primary complaints, clinical signs and mortality in forty-seven cases of uterine disorders diagnosed by ventrotomy in rabbits were analyzed retrospectively. Endometrial hyperplasia (29.8%) was most frequently observed, followed by uterine adenocarcinoma (21.3%). Tumorous lesions were seen in 46.8% of the cases. The age of occurrence ranged from two years and two months to seven years and six months, with a peak at four to five years of age. The most common primary complaint was bleeding (62.2%), followed by mammary gland abnormality (12.8%) and increased abdominal circumference (10.6%). Physical examinations revealed mammary gland disorders such as mammary cysts in 31.9% of the cases. Uterine disorders were detected by palpation in 15 out of 32 cases with a primary complaint of bleeding. Ultrasonography showed uterine disorders in 21 out of 24 cases, suggesting that ultrasonography could be useful in the diagnosis of uterine disorders. The outcome seemed to be influenced by physical status rather than malignancy of lesions. The mortality was higher in cases with symptoms such as anorexia, emaciation, severe anemia, and dehydration. 相似文献
106.
Setoyama K Ota H Miura N Fujiki M Misumi K Sakamoto H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(6):499-503
Milrinone, a therapeutic agent for acute congestive heart failure, has both inotropic and vasodilatory effects, but investigations of these effects of milrinone were almost all conducted under normoxia, and few reports have investigated how milrinone affects the hemodynamics and redistribution of regional blood flow under severe hypoxia. By using colored microspheres, we investigated how milrinone affects hemodynamics and the redistribution of regional blood flow under severe hypoxia. Twelve healthy mongrel dogs were divided into 2 groups. The milrinone group was infused with milrinone cumulatively at 25, 75 and 250 microg/kg for 5 min each. The intact group was infused with saline instead of milrinone. We measured the hemodynamics and cerebrum, cerebellum and kidney blood flow in both groups. Both groups were inspired with 10% oxygen. Milrinone induced significant decrease in mean pulmonary artery and pulmonary vascular resistance, compared with the intact group. In both groups slight decreases in mean arterial pressure, systemic vascular resistance and double-product were seen. In regional blood flow, milrinone-induced increases in blood flow were seen in the cerebrum, cerebellum, and especially in the kidneys. Milrinone's vasodilatory effects were sufficient even under hypoxia. And milrinone increased regional blood flow slightly in the cerebrum and cerebellum, and significantly in the kidneys. These results suggested that milrinone protects against hypoxia-induced organ damage especially in the kidneys. In addition, milrinone is very potent in improving severe congested hemodynamics which complicates hypoxic pulmonary vasoconstriction. 相似文献
107.
Ishioka K Soliman MM Sagawa M Nakadomo F Shibata H Honjoh T Hashimoto A Kitamura H Kimura K Saito M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(4):349-353
Leptin is a protein synthesized and secreted primarily by adipocytes, and the circulating leptin concentration is elevated in obese humans and rodents. Recently, we have established a sandwich enzyme-linked immunosorbent assay for canine leptin. In the present study, plasma leptin concentrations were measured in experimentally developed obese beagles and in clinically obese dogs. When 5 male beagles were given a high-energy diet for 3 months, all of them became obese and the plasma leptin concentration significantly increased from 2.4+/-1.2 to 4.9+/-0.9 ng/ml, positively correlating with body fat content estimated by the deuterium oxide dilution method (r=0.87). The leptin concentrations of plasma samples collected from 59 dogs in veterinary practices were compared with their body condition scores (BCS). The plasma leptin concentrations of obese dogs were 9.7+/-0.7 and 12.3+/-1.5 ng/ml at BCS=4 and BCS=5, respectively, which were significantly higher than those of optimal (BCS=3) dogs (2.7+/-0.3 ng/ml). There was no significant effect of sex and breed. A weak positive correlation (r=0.37) was found between the plasma leptin concentration and age, probably due to the lesser content of visceral fat in puppies younger than 1 year old. These results indicate that plasma leptin is a good index of adiposity in dogs regardless of breed, age and sex, and may be useful for quantitative assessment of obesity in small animal practice. 相似文献
108.
Masuda K Sakaguchi M Saito S Deboer DJ Yamashita K Hasegawa A Ohno K Tsujimoto H 《Veterinary dermatology》2002,13(1):55-61
Three dogs were examined because of episodes of recurrent pruritic dermatitis in the spring, the season of Japanese cedar (Cryptomeria japonica, CJ) pollination in Japan. The dogs were shown to be sensitive to CJ pollen allergen using intradermal testing and antigen-specific IgE measurement. Fluorometric enzyme-linked immunosorbant assay (ELISA) showed increased concentrations of IgE specific to Cry j 1 and a negative result for Cry j 2 in the three dogs. The concentrations of IgE specific to Cry j 1 during the season of CJ pollination were higher than the concentrations found during the off-season in all the dogs, and the variation in the concentrations correlated with the variation in clinical signs. Peripheral blood mononuclear cells showed apparent proliferative responses to crude CJ pollen antigen and Cry j 1 during CJ pollination season. These findings indicated that Cry j 1 was the major allergen recognized by IgE and lymphocytes and resulted in the development of type I hypersensitivity to CJ pollen allergen in these atopic dogs. 相似文献
109.
Hosaka Y Kirisawa R Yamamoto E Ueda H Iwai H Takehana K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(10):945-947
Although inflammatory activation of cytokines have been analyzed in various tissues, there have only been a few and as-yet-inconclusive studies on cytokines in equine tendons. In this study, the localizations of 4 cytokines (IL-1alpha, IL-1beta, TNFalpha and IFNgamma) in tendinocytes of the equine superficial digital flexor tendon (SDFT) were analyzed by the use of an immunohistochemical method. In inflamed tendons positive staining for all 4 cytokines antibodies were detected in endotedinieum cells and vascular epithelial cells. In contrast, negative or trace immunoreactions were obtained in many tendinocytes in the normal tendon. The variation in cellular immune responses depending on the kind of cytokine may reflect the physiological/pathological condition of the SDFT. 相似文献
110.
Saito M Kubo M Itagaki H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(11):1209-1211
Sarcocystis sp. was detected from cattle slaughtered in Saitama Prefecture, Japan. The cysts were 3,400-4,400 x 198-238 microm in size and had the thick cyst wall which was 7 to 10 microm thick and provided with finger-like villar protrusions. The protrusions were 8-9.5 x 2-2.5 microm in size and had microtubules in the core. 相似文献