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71.
The Pennsylvania egg quality assurance program (PEQAP) has made major gains in the reduction of Salmonella enterica serotype enteritidis (S. enteritidis). However, S. enteritidis continues to be a major food safety concern for the commercial egg laying industry. Despite intensive control efforts through PEQAP, some commercial egg layer houses still remain positive for S. enteritidis. The primary objective of this study was to determine whether S. enteritidis isolates obtained from historically environmentally S. enteritidis-positive houses were resistant to commonly used disinfectants. Archived S. enteritidis isolates (environmental, rodent, or egg) were compared with recently obtained isolates from the environment, rodents, or eggs from the same S. enteritidis-positive house. In addition, the isolates were compared with archived isolates from those premises that appeared to have eliminated S. enteritidis from their layer facilities. The official methods of the use-dilution analysis of the Association of Official Analytical Chemists were used to evaluate each disinfectant product. Two phenolic, one quaternary ammonium, and one combination product containing quaternary ammonium and formaldehyde were evaluated, in addition to one sodium hypochlorite detergent. All products diluted according to the manufacturers' recommendations killed the S. enteritidis isolates in this test system. There was no difference in susceptibility or resistance to the disinfectants used between the isolates from those facilities that remained S. enteritidis-positive and those that appeared to have eliminated S. enteritidis from their facility.  相似文献   
72.
Familial nonspherocytic hemolytic anemia in poodles   总被引:1,自引:0,他引:1  
Nonspherocytic hemolytic anemia, characterized by marked reticulocytosis, hepatosplenomegaly, hemosiderosis of reticuloendothelial organs and bone marrow myelofibrosis, and osteosclerosis, was diagnosed in 5 related Poodles. The unremitting anemia was clinically evident by 1 year of age, and was fatal as early as 3 years of age. Despite intense diagnostic endeavors including RBC fragility studies, RBC enzyme assays, and hemoglobin electrophoresis, the cause of this nonspherocytic hemolytic anemia remains to be determined.  相似文献   
73.
Glomerulonephritis (GN) is a leading cause of chronic renal failure in dogs. However, little is known about the efficacy of available treatment options for GN in this species. The purpose of this study was to determine the effects of cyclosporine (Cy) administration on the outcome of naturally occurring GN in dogs. Thirteen dogs from 4 institutions were included in the study. Randomization of dogs into placeboversus Cy-treated groups was stratified according to initial morphological diagnosis and contributing institution. Seven and 6 dogs were assigned to be given placebo or Cy, respectively. The initial Cy dose of 10 mg/kg every 24 hours was adjusted to maintain 24-hour trough, whole blood Cy concentrations between 250 and 400 ng/mL. There were no statistically significant differences between placebo-and Cy-treated groups with respect to serum total protein, albumin, urea nitrogen and creatinine, and plasma protein concentrations; platelet count; urine protein-creatinine ratio; endogenous creatinine clearance; 24-hour urine protein concentrations; or 24-hour urine protein—endogenous creatinine clearance ratio. However, PCV was significantly lower in the Cy-treated group. Decreased appetite, diarrhea, vomiting, weight loss, involuntary shaking, and thrombocytopenia were noted in both treatment groups; however, clinical signs in Cy-treated dogs subjectively were more severe. One Cy-treated dog developed gingival hyperplasia. After entry into the study, the median survival times for placebo-and Cy-treated dogs were 16 and 11 months, respectively. Considering the expense and the frequency of adverse effects related to Cy administration, the use of Cy in the treatment of dogs with GN does not seem warranted.  相似文献   
74.
Chronic kidney disease (CKD) is a major health condition in cats that can lead to poor quality of life and financial implications for therapy. Currently staging and identification of CKD is limited by diagnostic testing such as creatinine and urine-specific gravity, which do not change until late in the disease course. Other methods to evaluate CKD would be valuable in the clinical setting. Shear wave elastography is one novel ultrasound method, which has shown promise in identifying increases in tissue stiffness and identifying CKD in people. As CKD is often histologically characterized by tubulointerstitial fibrosis, shear wave elastography has the potential to identify CKD and differentiate between stages of CKD in cats. This prospective observational case-control study with 78 cats found no difference in shear wave velocities between groups (P = 0.33), a contradictory finding to one prior publication. There was no effect of weight (P = 0.65), nor the presence of mineralization (P = 0.31) or infarction (P = 0.52) on cortical shear wave velocities. There was a significant effect of age on shear wave velocity (P = 0.018) where velocities increased with age. The intraclass correlation coefficient was only moderate (0.62). Possible reasons for the difference in results between our work and that published prior, include differences in methodology and differences in instrumentation. Variability in measurements in our population may be due to the effects of respiratory motion or limitations in shear wave elastography software. As such, shear wave elastography is not currently recommended as a tool to evaluate CKD in cats and further work is necessary.  相似文献   
75.
This paper will visually show, through the use of historic and contemporary photographs, that the National Reclamation Act is a cornerstone of growth in the West. The irrigation works constructed under the federal reclamation program provided a stable water supply for crops, transforming the desert to the farmlands, and continued with the development of cities, businesses, and communities. Hydropower, a by-product of water development, initially operated irrigation pumps and lighted homes, and now powers industries. Salt River Project (SRP), as one of the first multi-purpose reclamation projects authorized by the federal government, provided irrigation water to the settlers of the Salt River Valley at the beginning of the twentieth century. Over 100 years later, SRP continues that tradition and is still delivering water to its shareholders and customers, but now in an urban setting.  相似文献   
76.
This research investigates the effects of heating conditions used to produce amorphous sucrose on its glass transition (T(g)) parameters, because the loss of crystalline structure in sucrose is caused by the kinetic process of thermal decomposition. Amorphous sucrose samples were prepared by heating at three different scan rates (1, 10, and 25 °C/min) using a standard differential scanning calorimetry (SDSC) method and by holding at three different isothermal temperatures (120, 132, and 138 °C) using a quasi-isothermal modulated DSC (MDSC) method. In general, the quasi-isothermal MDSC method (lower temperatures for longer times) exhibited lower T(g) values, larger ΔC(p) values, and broader glass transition ranges (i.e., T(g end) minus T(g onset)) than the SDSC method (higher temperatures for shorter times), except at a heating rate of 1 °C/min, which exhibited the lowest T(g) values, the highest ΔC(p), and the broadest glass transition range. This research showed that, depending on the heating conditions employed, a different amount and variety of sucrose thermal decomposition components may be formed, giving rise to wide variation in the amorphous sucrose T(g) values. Thus, the variation observed in the literature T(g) values for amorphous sucrose produced by thermal methods is, in part, due to differences in the heating conditions employed.  相似文献   
77.
世界各地,沙门氏菌和弯曲杆菌一直是经由食物传播疾病的最主要原因,多数情况下出现于禽类产品中。沙门氏菌的含量随季节、地域、群体和环境的改变而发生很大变化。研究人员发现家禽进入加工厂时沙门氏菌阳性率为3%~4%,而加工完成后则为20%~35%。因此,克服交叉感染是控制沙门氏菌的难题之一。由于工厂的自动化程度不同和生产过程中操作繁琐,所以交叉感染不易控制。更为重要的是,如果在养殖场就控制好病原菌,那么病原菌就不会进入加工厂,控制交叉感染也就不成问题。但是,大多数食品安全控制措施是在加工厂执行的。  相似文献   
78.
An analytical method has been developed that uses electron capture/gas-liquid chromatography to determine Mirex in serum containing polychlorinated biphenyls (PCBs) (Aroclor 1260). With this method, 0.2 ppb Mirex can be determined in 4 mL serum that also contains 10 ppb PCBs. The method provides approximately 70% recovery of Mirex at 1.0 and 3.5 ppb. The coefficients of variation are 4.5 and 4.6% at 1.0 and 3.5 ppb, respectively. In a cooperative study with the Ohio Department of Health, the Centers for Disease Control used this method to determine the extent of exposure of Salem, OH, residents to Mirex. Confirmation of Mirex was obtained by using high resolution gas chromatography and high resolution mass spectrometry.  相似文献   
79.
Glomerular diseases are a leading cause of chronic kidney disease in dogs but seem to be less common in cats. Glomerular diseases are diverse, and a renal biopsy is needed to determine the specific glomerular disease that is present in any animal. Familial glomerulopathies occur in many breeds of dogs. However, most dogs with glomerular disease have acquired glomerular injury that is either immune-complex mediated or due to systemic factors, both of which are believed to be the result of a disease process elsewhere in the body (i.e., neoplastic, infectious, and noninfectious inflammatory disorders). A thorough clinical evaluation is indicated in all dogs suspected of having glomerular disease and should include an extensive evaluation for potential predisposing disorders. Nonspecific management of dogs with glomerular disease can be divided into 3 major categories: (1) treatment of potential predisposing disorders, (2) management of proteinuria, and (3) management of uremia and other complications of glomerular disease and chronic kidney disease. Specific management of specific glomerular diseases has not been fully studied in dogs. However, it may be reasonable to consider immunosuppressive therapy in dogs that have developed a form of glomerulonephritis secondary to a steroid-responsive disease (e.g., systemic lupus erythematosus) or have immune-mediated lesions that have been documented in renal biopsy specimens. Appropriate patient monitoring during therapy is important for maximizing patient care. The prognosis for dogs and cats with glomerular disease is variable and probably dependent on a combination of factors. The purpose of this article is to discuss the general diagnosis and management of dogs with glomerular disease.  相似文献   
80.
Renal hematuria has limited treatment options. This report describes management of bilateral idiopathic renal hematuria in a dog with surgically assisted installation of 0.5% silver nitrate solution. Initial treatment resulted in freedom from clinical signs or recurrent anemia for 10 months; however, recurrence of bleeding following a nephrectomy resulted in euthanasia.  相似文献   
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