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11.
The frequency of enterotoxigenic coagulase-positive and coagulase-negative staphylococci in nose and throat and in hand lesions was investigated in 86 meat cutters and dressers. Enterotoxin-producing staphylococci were demonstrated in nasal swabs from 22% of clinically well workers and from 42% of a group with mild coryza. The corresponding rates in throat swabs were 6 and 12%. Four of 16 superficial lesions of the hand harbored enterotoxigenic staphylococci. The implications for contamination of food and outbreaks of staphylococcal food poisoning are discussed.  相似文献   
12.
OBJECTIVE: To evaluate viability of a probiotic strain of Lactobacillus acidophilus in a dry dog food, determine its ability to survive transit through the gastrointestinal tract and populate the colon, and assess its effects on intestinal and systemic parameters. ANIMALS: 15 adult dogs. PROCEDURE: Dogs were sequentially fed a dry control food for 2 weeks, the same food supplemented with > 10(9) L. acidophilus for 4 weeks, and the control food again for 2 weeks. Fecal score was assessed daily, and fecal and blood samples were collected for enumeration of bacterial populations and measurement of hematologic variables. RESULTS: Recovery of L. acidophilus from the supplemented food was 71% and 63% at the start and end of the study, respectively, indicating that the bacteria were able to survive manufacture and storage. The probiotic bacterium was detected in feces via ribotyping and RNA gene sequencing during the probiotic administration phase but not 2 weeks after cessation of administration. Administration of the probiotic-supplemented food was associated with increased numbers of fecal lactobacilli and decreased numbers of clostridial organisms. There were significant increases in RBCs, Hct, hemoglobin concentration, neutrophils, monocytes, and serum immunoglobin G concentration and reductions in RBC fragility and serum NO concentration. CONCLUSIONS AND CLINICAL RELEVANCE: These data indicate that L. acidophilus can be successfully incorporated into a dry dog food, survive transit through the canine gastrointestinal tract, and populate the colon and are associated with local and systemic changes. This probiotic bacterium may have the potential to enhance intestinal health and improve immune function in dogs.  相似文献   
13.
We have recently presented a method for the determination of quickly reacting aluminium in natural waters based on kinetic discrimination in a flow system. This method has been further validated using both an isolated fulvic acid and natural humus-rich waters. Different reaction times were used, further clarifying the response of aluminium complexed with humic and fulvic acids. Equilibrium dialysis was also used as a reference method for comparison. With the reaction time used normally, 2.3 s, aluminium complexed with humic or fulvic acids was shown not to be measured with our method. These results suggest that our method may be used for studies of the complexation of aluminium with humic and fulvic acids. We have compared results from a series of solutions with varying concentrations of fulvic acids with calculations based on two different models obtained from complexation studies performed by potentiometric titrations and by equilibrium dialysis. The results show fair agreement and suggest that our method can be used for such studies. This approach is more sensitive and rapid than potentiometric titrations, enabling studies of humus interactions with aluminium at concentrations similar to those found in natural waters.  相似文献   
14.
The formation of furan upon sterilization of a lipid-containing starch gel was investigated in the presence of various antioxidants, namely, α-tocopherol, β-carotene, and ascorbic acid, with and without proteins. Results indicated that α-tocopherol did not significantly influence furan formation from oxidized lipids. β-Carotene, suggested previously to be a furan precursor itself, did influence the generation of furan in a concentration-dependent manner, although to a limited extent. Surprisingly, the presence of lipids seemed to limit the furan generation from β-carotene. Interestingly, the addition of ascorbic acid to the emulsions containing soybean or sunflower oils considerably enhanced the formation of furan from these oils. This was also the case when fresh oils were applied, shown previously to be nearly unable to generate furan. This observation can be explained by an intensified ascorbic acid degradation stimulated by the presence of lipids.  相似文献   
15.

Background  

Photosynthetic sponges are important components of reef ecosystems around the world, but are poorly understood. It is often assumed that temperate regions have low diversity and abundance of photosynthetic sponges, but to date no studies have investigated this question. The aim of this study was to compare the percentages of photosynthetic sponges in temperate Western Australia (WA) with previously published data on tropical regions, and to determine the abundance and diversity of these associations in a range of temperate environments.  相似文献   
16.
The strength and fracture behavior of dowel-type connections with stiff dowels loaded perpendicular to grain was studied by nonlinear 3D finite element (FE)-analysis. A cohesive zone model was used to model the perpendicular to grain fracture of the wood, i.e., failure by wood splitting along the grain. The influence of load eccentricity and dowel-to-loaded-edge distance was studied for a plate type of geometry loaded in tension and for a simply supported beam loaded in bending. The strength found from the FE-analysis is compared to strength from experimental tests with centric loading, showing overall good agreement. Numerical results for centric loading are further compared to strength predictions according to the linear elastic fracture mechanics (LEFM)-based design criterion present in Eurocode 5 (EN 1995-1-1:2004). The comparison showed good agreement regarding the relative influence of connection geometry, but the design criterion appears, however, to yield unconservative strength predictions. The results of the FE-analyses regarding dowel load eccentricity showed that such loading conditions may yield significantly lower strengths compared to centric loading. An approximate engineering method to account for the strength reduction due to load eccentricity is, furthermore, presented.  相似文献   
17.
AIM: To report the long-term outcome (return to work and owner satisfaction) following surgical treatment of common calcanean tendon (Achilles tendon) injuries in working dogs in New Zealand. METHODS: Ten New Zealand Huntaway or Heading dogs (working Collies) with complete or partial tears of the common calcanean tendon, were treated using locking-loop suturing and casting, with (7) or without (3), a calcaneo-tibial screw. All dogs were actively in work on sheep or cattle farms at the time of injury, and return to work was the desired outcome. Ability to work and owner satisfaction were investigated using a telephone questionnaire at a mean followup interval of 14.6 months. RESULTS: Overall, 7/10 dogs returned to full or substantial levels of work. Post-operative complications occurred in two dogs that did not return to full or substantial levels of work. Moderate persistent lameness (score 3 on a scale of 0-5) was present in 2/7 dogs that returned to full or substantial levels of work, equating to a 71% good-to-excellent functional outcome within this group. Seven owners felt the financial investment in opting for surgical repair was worthwhile. A screw and cast method of rigid immobilisation was thought to be superior to casting alone. CONCLUSIONS: Surgical treatment of common calcanean tendon injury in working dogs carries a good prognosis if an appropriate tenorrhaphy technique is used and rigid immobilisation is achieved for 6 weeks. Care must be taken to limit post-operative complications. CLINICAL RELEVANCE: This study justifies the use of surgical repair of such injuries in the working dog even when return to work is the only acceptable outcome.  相似文献   
18.
OBJECTIVE: To evaluate the effect of dietary supplementation with the probiotic strain Lactobacillus acidophilus DSM13241 in healthy adult cats. ANIMALS: 15 adult cats. PROCEDURES: Cats were fed a nutritionally complete dry food for 5 weeks. Fecal character was assessed daily, and a single fecal sample and 3-mL blood sample were collected for bacterial enumeration and hematologic analysis, respectively. Cats were then fed the same diet supplemented with L acidophilus DSM13241 (2 x 10(8) CFU/d) for 4.5 weeks. Repeat fecal and hematologic measurements were taken prior to the return to control diet for a 4-week period. RESULTS: The probiotic species was recovered from feces, demonstrating survival through the feline gastrointestinal tract. Probiotic supplementation was associated with increased numbers of beneficial Lactobacillus and L acidophilus groups in feces and decreased numbers of Clostridium spp and Enterococcus faecalis, indicating an altered bacterial balance in the gastrointestinal tract microflora. Fecal pH was also decreased suggesting a colonic environment selective for the beneficial lactic acid bacterial population. Systemic and immunomodulatory effects were associated with administration of L acidophilus DSM13241 including altered cell numbers within WBC subsets and enhanced phagocytic capacity in the peripheral granulocyte population. In addition, plasma endotoxin concentrations were decreased during probiotic feeding, and RBCs had a decreased susceptibility to osmotic pressure. CONCLUSIONS AND CLINICAL RELEVANCE: Probiotic strain L acidophilus DSM13241 fed at 2 x 10(8) CFU/d can alter the balance of gastrointestinal microflora in healthy cats. Furthermore, administration of this probiotic results in beneficial systemic and immunomodulatory effects in cats.  相似文献   
19.
Measurements of stomatal conductance on field-grown potato (Solanum tuberosum L.) cv. Bintje from the CHIP programme were combined to study the response to environmental factors. 3274 data points were used. Data were obtained from five sites: Jokioinen in Finland, Östad in Sweden, Giessen in Germany, Tervuren in Belgium and Sutton Bonnington in UK. Measurements were made in open-top chamber treatments with ozone and carbon dioxide exposure and in the ambient air. A typical light response curve was obtained with light saturation at approximately 400 μmol m−2 s−1 photosynthetically active radiation (PAR). The leaf temperature optimum for stomatal conductance was 29 °C. The stomatal conductance declined strongly at leaf-to-air vapour pressure differences >20 hPa. An elevated carbon dioxide concentration (680 μl l−1) reduced the stomatal conductance by up to approximately 20%. Elevated ozone reduced the stomatal conductance towards the end of the growth period, in addition to the negative effect by ordinary senescence on stomatal conductance. A multiplicative model, based on the boundary line technique, was used to estimate the relationship between stomatal conductance and the environmental variables. Test with the data sets from two sites providing sufficient data, Östad and Giessen, showed that the multiplicative model had R2-values of 0.60 and 0.42, respectively, for the relationship between calculated and observed conductance. Test of the model with an independent data set from an open-top chamber experiment with the potato cultivar Kardal showed an R2 of 0.59 between calculated and observed conductance. The conductance model was used to estimate the accumulated ozone uptake (CUO3) by potato leaves from emergence to harvest. The relationship between CUO3 and relative yield loss, using a threshold for the ozone uptake rate of 7 nmol m−2 s−1, provided a higher R2-value (0.45) than CUO3 without any threshold and relationships based on the accumulated exposure over 40 nmol mol−1 (AOT40) or the sum of all hourly average ozone concentrations exceeding 60 nmol mol−1 (SUM06). All four relationships were however statistically significant.  相似文献   
20.
Process parameter optimization for the supercritical CO(2) extraction of rye bran to obtain alkylresorcinols (AR) was studied by carrying out a two-level fractional design experiment. Four parameters, temperature, CO(2) flow rate, cosolvent percentage, and extraction time, presumed to influence the extraction process, were analyzed. A tentative fractionation of the crude extract was also carried out and is discussed. The best extracts were achieved when the CO(2) flow rate and extraction time or temperature and cosolvent addition were kept high. It was found that temperature increase was not statistically significant within the range of the study performed, and the extraction time was thus the most important factor. A preliminary fractionation process in two cyclone separators yielded two fractions, one rich in AR components with higher molecular weights and the other rich in AR components with low molecular weight.  相似文献   
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