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151.
Shiga toxin-producing Escherichia coli (STEC) are a public health concern. Bacterial culture techniques commonly used to detect E. coli O157:H7 will not detect other STEC serotypes. Feces from cattle and other animals are a source of O157:H7 and other pathogenic serotypes of STEC. The objective of this study was to estimate the pen-level prevalence of Shiga toxins and selected STEC serotypes in pre-slaughter feedlot cattle. Composite fecal samples were cultured and a polymerase chain reaction (PCR) was used to detect genes for Shiga toxins (stx1 and stx2) and genes for O157:H7, O111:H8, and O26:H11 serotypes. Evidence of Shiga toxins was found in 23 pens (92%), O157:H7 in 2 (8%), O111:H8 in 5 (20%), and O26:H11 in 20 (80%) of the 25 pens investigated. Although pen-level prevalence estimates for Shiga toxins and non-O157 serotypes seem high relative to O157:H7, further effort is required to determine the human health significance of non-O157 serotypes of STEC in feedlot cattle.  相似文献   
152.
Feline aggression towards people has a smaller incidence than canine aggression, but also represents an important public health problem. The aim of this work was to analyse feline aggression reported towards people, to estimate its incidence and to assess the risk factors involved. The information was obtained from the Public Health Centres in the Valencian Region (Spain). A total of 936 acts of feline aggression were analysed. Cats inflicted 8% of all animal bites reported. The annual average was 6.36 feline aggression incidents per 100,000 people. Most aggressive incidents occurred during the summer months. Children (0-14 years old) and women were more likely to be bitten. Wounds were mainly punctures, single, and mild, and were located mostly on the hands. In children, the head and neck areas were affected much more than in adults. The cats involved in incidents were mostly Siamese, female and owned; these cats mainly attacked their owners. Most occurrences were a defensive response by the cat.  相似文献   
153.
Immunosuppressive effects of an intranasal challenge with non-cytopathic bovine viral diarrhea virus (BVDV) 2a (strain 1373) were assessed through acquired and innate immune system responses to ovalbumin (OVA). Concurrent BVDV infection was hypothesized to delay and reduce the humoral response to ovalbumin (administered on days 3 and 15 post-inoculation). Infected animals followed the expected clinical course. BVDV titers, and anti-BVDV antibodies confirmed the course of infection and were not affected by the administration of OVA. Both the T-helper (CD4+) and B-cell (CD20+) compartments were significantly (P < 0.05) reduced in infected animals, while the gamma-delta T-cell population (Workshop cluster 1+, WC1+) decreased slightly in numbers. Infection with BVDV delayed the increase in OVA IgG by approximately 3 d from day 12 through day 21 post-inoculation. Between days 25 and 37 post-inoculation following BVDV infection the IgM concentration in the BVDV− group decreased while the OVA IgM titer still was rising in the BVDV+ animals. Thus, active BVDV infection delays IgM and IgG responses to a novel, non-infectious antigen.  相似文献   
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Despite its common occurrence, the aetiology of chronic gingivostomatitis in cats remains uncertain. Aetiology is likely multifactorial, and several infectious agents may be associated with chronic gingivostomatitis. The purpose of this study was to investigate the prevalence of feline calicivirus (FCV), feline immunodeficiency virus (FIV), feline leukemia virus (FeLV), feline herpesvirus (FHV), and Bartonella henselae (B. henselae) in cats with chronic gingivostomatitis and in an age-matched control group. In addition, other factors, e. g., environmental conditions were investigated. In 52 cats with chronic gingivostomatitis and 50 healthy age-matched control cats, the presence of FCV ribonucleic acid (RNA), and FHV deoxyribonucleic acid (DNA) (polymerase chain reaction [PCR] from oropharyngeal swabs), and B. henselae DNA (PCR from oropharyngeal swabs and blood), as well as FeLV antigen (serum), and antibodies against FCV, B. henselae, and FIV (serum) were examined. FCV RNA was significantly more common in cats with chronic gingivostomatitis (53.8%, p < 0.001) than in controls (14.0%); a significant difference was also found in the prevalence of antibodies to FCV between the cats with chronic gingivostomatitis (78.8%, p = 0.023) and controls (58.0%). Of the other infectious agents investigated, there was no significant difference in the prevalence between the cats with chronic gingivostomatitis and the controls. The results of this study allow the conclusion that FCV, but no other infectious agents, is commonly associated with chronic gingivostomatitis in cats.  相似文献   
157.
Consumption of whole grains as part of a health‐promoting diet is encouraged among Americans due to beneficial nutrients and phytochemicals. The main objectives of this study were to investigate the effect of whole barley flour particle size on consumer acceptance of whole grain and soluble fiber‐enriched tortillas; to examine the effect of demographic and behavioral data on consumer acceptance; and to establish relationships between consumer acceptance and survey results to identify market opportunities among particular groups of consumers. Four experimental tortillas and two representative commercial brands were tested by 95 untrained panelists using a 9‐point hedonic scale for appearance, color, flavor, texture, and overall acceptability. Demographic and behavioral data on age, gender, ethnicity, frequency of tortilla consumption, daily effort to include fiber in the diet, consumption of tortillas containing ≥1 g of dietary fiber/serving, consumption of low‐fat tortillas, and tortilla brands and type used were collected. Potential market segments for these tortillas include older consumers (41+), women, Hispanics, and Asians, and frequent tortilla consumers. A response surface relating flavor and texture to overall acceptability produced almost equivalent results to the multivariate PLS results in terms of predicting overall acceptability, which facilitates analysis and interpretation.  相似文献   
158.
A combination of on-line HPLC-NMR and off-line chemical investigations has resulted in the identification of the previously reported polyhalogenated monoterpene plocamenone, together with the new structural analogue isoplocamenone from the crude extract of the marine alga Plocamium angustum. On-flow and stop-flow HPLC-NMR analyses (including the acquisition of WET 2D NMR spectra) rapidly assisted in the identification of the major component plocamenone and in the partial identification of its unstable double bond isomer isoplocamenone. Conventional off-line isolation and structural characterization techniques were employed to unequivocally confirm both structures, leading to a structural revision for plocamenone, as well as to obtain sufficient quantities for biological testing.  相似文献   
159.
Antifungal bioactivity-guided fractionation of the organic extract of the sponge Polymastia boletiformis, collected from the west coast of Ireland, led to the isolation of two new sulfated steroid-amino acid conjugates (1 and 2). Extensive 1D and 2D NMR analyses in combination with quantum mechanical calculations of the electronic circular dichroism (ECD) spectra, optical rotation, and 13C chemical shifts were used to establish the chemical structures of 1 and 2. Both compounds exhibited moderate antifungal activity against Cladosporium cucumerinum, while compound 2 was also active against Candida albicans. Marine natural products containing steroidal and amino acid constituents are extremely rare in nature.  相似文献   
160.
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