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731.
Doménech N Bullido R Alvarez B Campos E Rodríguez-Carreño MP Gómez Del Moral M Alonso F Ezquerra A Domínguez J 《Veterinary research》2004,35(3):339-348
In this report, we describe the characterization of a novel activation antigen on porcine lymphocytes recognized by mAb 5A6/8. This antigen was detected on B and T cells 24 h after treatment with various stimuli. It was also found on alveolar macrophages, and at low levels on untreated monocytes. MAb 5A6/8 precipitated two bands of 45 and 50 kDa under non-reducing conditions, and of 22 and 28 kDa under reducing conditions. The cellular distribution, expression kinetics and/or molecular size of the 5A6/8 antigen differ from those of other known lymphocyte activation antigens. MAb 5A6/8 was able to inhibit lymphocyte proliferative responses driven by different stimuli, suggesting a role for this molecule in the events that lead to lymphocyte activation. 相似文献
732.
MacGillivray KC Sweeney RW Del Piero F 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2002,16(4):452-456
The clinical and pathologic findings are reviewed for 14 horses with metastatic melanoma. All were older gray horses, with an average age of 16 years. The most common sites of primary tumors were the ventral tail, perineum, and parotid salivary gland. Metastases were found in multiple locations and caused a variety of clinical syndromes. The most common sites for metastases were the lymph nodes, liver, spleen, skeletal muscle, lungs, and surrounding or within blood vessels throughout the body. Many of the horses had dermal melanomas for years (range 1-6 years) before succumbing to metastatic disease. Histologic characteristic of dermal masses was not predictive of malignancy in the majority of cases. Treatment consisting of surgical debulking and administration of cimetidine, an autogenous vaccine, or both was attempted in 4 horses with no effect on outcome. 相似文献
733.
Driessen B Zarucco L Steffey EP McCullough C Del Piero F Melton L Puschner B Stover SM 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2002,49(7):337-347
The volatile anaesthetic sevoflurane is degraded to fluoride (F-) and a vinyl ether (Compound A), which have the potential to harm kidney and liver. Whether renal and hepatic injuries can occur in horses is unknown. Cardiopulmonary, biochemical and histopathological changes were studied in six healthy thoroughbred horses undergoing 18 h of low-flow sevoflurane anaesthesia. Serum F- concentrations were measured and clinical laboratory tests performed to assess hepatic and renal function before and during anaesthesia. Necropsy specimens of kidney and liver were harvested for microscopic examination and compared to pre-experimental needle biopsies. Cardiopulmonary parameters were maintained at clinically acceptable levels throughout anaesthesia. Immediately after initiation of sevoflurane inhalation, serum F- levels began to rise, reaching an ongoing 38-45 micromol 1(-1) plateau at 8 h of anaesthesia. Serum biochemical analysis revealed only mild increases in glucose and creatinine kinase and a decrease in total calcium. Beyond 10 h of anaesthesia mild, time-related changes in urine included increased volume, glucosuria and enzymuria. Histological examination revealed mild microscopic changes in the kidney involving mainly the distal tubule, but no remarkable alterations in liver tissue. These results indicate that horses can be maintained in a systemically healthy state during unusually prolonged sevoflurane anaesthesia with minimal risk of hepatocellular damage from this anaesthetic. Furthermore, changes in renal function and morphology observed after sevoflurane inhalation are judged minimal and appear to be clinically irrelevant; they may be the result of anaesthetic duration, physiological stressors, sevoflurane (or its degradation products) or other unkown factors associated with these animals and study conditions. 相似文献
734.
McEwen MM Gleed RD Ludders JW Stokol T Del Piero F Erb HN 《Journal of the American Veterinary Medical Association》2000,217(11):1697-1700
OBJECTIVE: To determine hepatic effects of halothane and isoflurane anesthesia in young healthy goats. DESIGN: Randomized prospective clinical trial. ANIMALS: 24 healthy 9-month-old female goats. PROCEDURE: Goats were sedated with xylazine hydrochloride and ketamine hydrochloride and anesthetized with halothane (n = 12) or isoflurane (12) while undergoing tendon surgery. End-tidal halothane and isoflurane concentrations were maintained at 0.9 and 1.2 times the minimal alveolar concentrations, respectively, and ventilation was controlled. Venous blood samples were collected approximately 15 minutes after xylazine was administered and 24 and 48 hours after anesthesia, and serum aspartate aminotransferase (AST), sorbitol dehydrogenase (SDH), alkaline phosphatase (ALP), and gamma-glutamyltransferase (GGT) activities and bilirubin concentration were measured. Goats were euthanatized 25 or 62 days after anesthesia, and postmortem liver specimens were submitted for histologic examination. RESULTS: All goats recovered from anesthesia and survived until euthanasia. Serum SDH, GGT, and ALP activities and bilirubin concentration did not increase after anesthesia, but serum AST activity was significantly increased. However, serum hepatic enzyme activities were within reference limits at all times in all except 1 goat in which serum AST activity was high 24 and 48 hours after anesthesia. This goat had been anesthetized with halothane and had the longest duration of anesthesia. No clinically important abnormalities were seen on histologic examination of liver specimens. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that use of halothane or isoflurane for anesthesia in young healthy goats is unlikely to cause hepatic injury. 相似文献
735.
Moretti A Piergili Fioretti D Boncio L Pasquali P Del Rossi E 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2000,47(6):433-439
The present study describes the isolation of Candida rugosa from young turkeys that died 10 days after the end of a therapeutic treatment for a recent outbreak of coccidiosis. Candida rugosa was isolated from the digestive tract of all the birds examined. This isolation is the first in turkeys and corroborates the fact that C. rugosa is an opportunistic yeast which circumvents host defences when other predisposing factors are present. 相似文献
736.
In postpartum cows expected to have corpora lutea (CL) of normal (norgestomet-treated) compared to short (control) life spans, function of the largest follicle increases after an increase in concentrations of prostaglandin F2 alpha (PGF). To determine whether PGF alters follicular growth and subsequent life span of the CL, 43 crossbred beef cows (19 to 22 d postpartum) were assigned to one of four treatments: 1) control (C; n = 10), 2) control+PGF (CPGF; n = 10), 3) norgestomet (N; n = 13), 4) norgestomet+flunixin meglumine (NFM; n = 10). Flunixin meglumine inhibits prostaglandin endoperoxide synthase. On day 0, N and NFM cows received a 6 mg implant of norgestomet. From days 3 through 8, CPGF and NFM cows were injected every 8 hr with 10 mg PGF im or 1 g FM iv, respectively. Implants were removed on day 9. On day 11, each cow received 1000 IU of hCG im to induce formation of CL. Follicular growth was monitored by daily ultrasonography from days 6 through 11. In a majority of the cases (25/32), the largest follicle present on day 6 was still the largest on day 11; frequency of persistence did not differ with treatment. Rate of growth of the largest follicle was greater in CPGF than in N cows (.6 +/- .1 vs .3 +/- .1 mm/d, respectively; P less than .05) but did not differ between C and NFM cows (.4 +/- .1 and .5 +/- .1 mm/d, respectively). Concentrations of estradiol in NFM cows were higher (P less than .05) on day 3 and declined to concentrations similar to those of the other treatments on day 9.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
737.
Activities of enzymes nitrate reductase (NR) and nitrite reductase (NiR) were determined in rice seedlings differing in salt tolerance raised under increasing levels of NaCl salinity. Salinity caused marked increase in in vivo NR activity in roots and shoots of salt tolerant cvs. CSR-1 and CSR-3 whereas in salt sensitive cvs. Ratna and Jaya a marked inhibition in in vivo NR activity was observed under salimzation. Under both controls as well as salt treatments in all cultivars roots always maintained higher level of in vivo NR activity than shoots. In vitro NR activity increased in both roots and shoots of all cultivars during early days of growth with maximum at 10–15 days and decreased thereafter. In salt tolerant cultivars salinity caused an increase in in vitro NR activity in shoots but not in roots whereas in salt sensitives activity of the enzyme was always more in salt stressed seedlings compared to controls. Salinity increased NiR activity in seedlings of sensitive cultivars whereas in tolerants suppression in root NiR activity was observed due to salinity. Like NR the activity of NiR was also higher in roots than shoots. 1 M NaCl in the enzyme assay medium suppressed in vivo NR activity in roots of 15 days old nonsalinized seedlings with more suppression in sensitive cultivars than tolerants. Results suggest possible different behaviours of nitrogen assimilatory enzymes in rice cultivars differing in salt tolerance and that salt tolerance ability is associated with high in vivo NR activity in seedlings and its further activation under salinization. 相似文献
738.
739.
Experimental histoplasmosis in gnotobiotic dogs 总被引:1,自引:0,他引:1
740.
Nieves Ortega José A Navarro Laura Nicolás Antonio J Buendía María R Caro Laura Del Río Carlos M Martínez Francisco Cuello Jesús Salinas María C Gallego 《Journal of veterinary diagnostic investigation》2007,19(4):421-425
Polymerase chain reaction (PCR) has gained increasing importance as a tool for directly demonstrating the presence of Chlamydophila in the placentas of aborted sheep and goats. However, because of the zoonotic potential of the disease, it is advisable to use fixed materials. To evaluate 4 different DNA extraction protocols in paraffin-embedded sections for PCR, previously immunohistochemically diagnosed placental samples from outbreaks of abortions in goats and sheep were used. The samples were also used to evaluate the effect of the duration of fixation in formalin on PCR. A protocol that uses Tris-HCl pH 8.5 with EDTA and subsequent digestion with proteinase K was found to be an easy protocol for obtaining excellent PCR products for Chlamydophila abortus diagnosis from formalin-fixed and paraffin-embedded specimens. It was also found that if samples are fixed in formalin for more than 2 weeks, the PCR technique is affected more adversely than immunohistochemical methods. 相似文献