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41.
Changes in quality characteristics in relation to protease activity and protein oxidation in chilled, superchilled and frozen mackerel fillets during storage were studied. The solubility of sarcoplasmic proteins was quite stable in mackerel samples for all storage experiments, whereas the solubility of myofibrillar proteins decreased in both superchilled and frozen samples. A significant correlation (r = 0.983, P < 0.05) between the increased activity of cathepsin B+L in chilled fillets and softening of the fish flesh during storage was revealed. Contrary with chilled samples, the texture of superchilled mackerel fillets became tougher along the storage period, which can be explained by a higher rate of myofibrillar oxidation (r = 0.940, P < 0.05). The hardness and drip loss decreased slightly at the end of frozen storage. Superchilling preserved the quality of mackerel fillets with the least side effects in relation to protein solubility, drip loss and softening of the fish tissue as compared to chilled and frozen storage.  相似文献   
42.
The aim of this study was to evaluate if phospholipid profiles obtained by 13C nuclear magnetic resonance (NMR) spectroscopy is characteristic enough to separate species of lean gadoid fish. 13C NMR data were obtained from muscle lipids of five categories of lean gadoid fish, namely, north-east arctic cod and Norwegian coastal cod (Gadus morhua), haddock (Melanogrammus aeglifinus), saithe (Pollachius virens), and pollack (P. pollachius). A total of 27 fish caught at the same location on the Norwegian coast in the traditional fishing season (March/April) in 2006 were analysed. The sn-2 position specificity of 22:6n-3 (docosahexaenoic acid, DHA) in phosphatidyl choline (PC) and phosphatidyl ethanolamine (PE) for the different species/stocks were investigated, and the full 13C NMR spectra applied in multivariate analysis. Stereospecific distribution calculations showed significant differences among species in the distribution of 22:6n-3 in PC and PE, and the pollack group displayed the lowest values for 22:6n-3 in sn-2 position, both in PC and PE. This first screening showed that by using the 13C NMR fingerprint of muscle lipids, linear discriminant analysis gave a correct classification rate of 78% according to the five categories of lean gadoid fish, while successful classification (100%) was achieved with Bayesian belief networks (BBN) predictions.  相似文献   
43.
Colorectal cancer screening   总被引:4,自引:0,他引:4  
Signals elicited by transforming growth factor-beta (TGF-beta) superfamily ligands are generated following the formation of heteromeric receptor complexes consisting of type I and type II receptors. TAK1, a member of the MAP kinase kinase kinase family, and its activator, TAB1, participate in the bone morphogenetic protein (BMP) signaling pathway involved in mesoderm induction and patterning in early Xenopus embryos. However, the events leading from receptor activation to TAK1 activation remain to be identified. A yeast interaction screen was used to search for proteins that function in the pathway linking the receptors and TAB1-TAK1. The human X-chromosome-linked inhibitor of apoptosis protein (XIAP) was isolated as a TAB1-binding protein. XIAP associated not only with TAB1 but also with the BMP receptors in mammalian cells. Injection of XIAP mRNA into dorsal blastomeres enhanced the ventralization of Xenopus embryos in a TAB1-TAK1-dependent manner. Furthermore, a truncated form of XIAP lacking the TAB1-binding domain partially blocked the expression of ventral mesodermal marker genes induced by a constitutively active BMP type I receptor. These results suggest that XIAP participates in the BMP signaling pathway as a positive regulator linking the BMP receptors and TAB1-TAK1.  相似文献   
44.
This study converted the Teen-Addiction Severity Index (T-ASI) into self-report formats using Internet (Net) and interactive voice response (IVR) automated-telephone technologies. Reliability and convergent validity were assessed among 95 inpatient adolescent participants. Current functioning scores obtained by clinician interview correlated well with self-report Net (mean r = .74, SD = .14) and IVR (mean r = .72, SD = .16). Lifetime history items obtained by clinicians were consistent with self-report Net (mean r = .60, SD = .32; mean κ = .67, SD = .24) and IVR formats (mean r = .60, SD = .30; mean κ = .64, SD = .26). Participants rated "ease of use" as being high for both Net and IVR formats. These findings suggest that automated T-ASI administration is a valid and potentially less expensive alternative to clinician-administered T-ASI interviews. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
45.
Unfortunately, students can graduate with a software engineering degree without learning anything about building secure systems. However, for the past two years at the Norwegian University of Science and Technology, a software security course has been giving students the theoretical foundation and practical experience necessary to start comprehending software security issues.  相似文献   
46.
We present a model based approach to diagnosability analysis for interacting finite state systems where fault isolation is deferred until the system comes to a standstill. Local abstractions of the system model are used to alleviate the state space explosion. Pairs of closely coupled automata are merged and replaced by a single automaton with an equivalently behavior as seen from the rest of the system; interaction between the merged automata is internalized and the new equivalent automaton is subsequently abstracted from internal behavior irrelevant to fault isolation. In moderately concurrent systems these steps can often be iterated until the system consists of a single automaton providing a compact encoding of all possible fault scenarios of the original model. We illustrate how the resulting abstraction can be used as a basis for post mortem diagnosability analysis.  相似文献   
47.
The primary aim of this study was to evaluate if an ingested probiotic, containing viable Enterococcus faecium could survive gastrointestinal transit and if so, correlate the amount of the recovered probiotic strain with the host's own enterococci. The second aim was to investigate if simultaneous vancomycin intake influenced the survival and persistence of the probiotic strain and the stability of endogenous enterococci strains. Twenty healthy volunteers were given the probiotic product once daily for 10 days. Half of the subjects were simultaneously given vancomycin. Isolates of E. faecium strains were genotypically or phenotypically analysed with pulsed-field gel electrophoresis (PFGE) and the PhenePlate system, respectively. In eight of the ten volunteers given only the probiotic, the ingested E. faecium could be detected on day 10, while in none on day 31. From subjects given both probiotic and vancomycin no ingested E. faecium could be detected on day 10 or day 31. The estimated amount of ingested E. faecium recovered from faeces on day 10 ranged from 1.2 x 10(3) to 4.2 x 10(6) colony forming units per gram faeces, which in several cases were a substantial part of the total amount of E. faecium. The E. faecium isolated before probiotic plus vancomycin administration showed no close relationship to the ones isolated 3 weeks after ceased intake in any subjects. In conclusion, the ingested E. faecium strain can survive gastrointestinal transit. After intake, the E. faecium probiotic strain might become a large part of the total E. faecium population. The occurrence of the probiotic strain in the human gut seems to be transient after intake stop. Re-colonization of E. faecium after simultaneous probiotic plus vancomycin intake occurs mainly with strains without close genetic relationship to the strains harboured before treatment or to the ingested E. faecium strain.  相似文献   
48.
Release rates of chromium and nickel from pickled and skin passed 304 and 316 stainless steel have been determined during a one-year field exposure in an urban environment (Stockholm, Sweden) and through complementary exposures in artificial rain. Measured annual release rates from 304 stainless steel are 0.25-0.3 mg Cr/m2 and 0.3-0.4 mg Ni/m2, and slightly higher from 316 stainless steel, 0.35-0.4 mg Cr/m2 and 0.7-0.8 mg Ni/m2. The release rates decrease as the rain pH increases and exhibit no direct influence by rain intensity. Variations in release rates are thought to be a result of a non-uniformly attack.  相似文献   
49.
The pyrrolizidine alkaloid content of crude borage oil and borage oil from different processing stages was determined by GC-MS. The results showed that no pyrrolizidine alkaloids were present above a detection limit of 20 ppb. The reduction factors for pyrrolizidine alkaloids at various stages in the oil refining process were determined by means of spiking experiments using the commercially available pyrrolizidine alkaloid crotaline. It was shown that the pyrrolizidine content in crude borage oil was reduced overall by a factor of about 30,000 in the refining process.  相似文献   
50.
The growing interest in ecological investigations, such as studies of the "flow" of bacteria through the food chain, has resulted in a great need for simple typing techniques for bacteria that can be used when a large number of isolates need to be analysed. The present study describes a simple method for biochemical fingerprinting of enterococci, the PhenePlate RF (PhP-RF) system. The system is based on a 96-well microplate containing eight sets of 11 dehydrated reagents, selected to have a high discriminatory power among enterococcal isolates. The PhP plates are inoculated easily by picking single colonies directly from the primary agar culture and suspending them in the first well of each row in the microplate. The kinetics of each reaction is evaluated by measuring the absorbance value of each well three times during 64 h, whereupon a biochemical fingerprint is calculated as the mean value for each reagent over the three readings. The PhP-RF method was shown to be highly reproducible, even when results were compared between different laboratories. The discriminatory power, measured as Simpson's diversity index (Di), was as high as 0.96 for all enterococci. The PhP-RF method could also be used as a preliminary species identification method, by comparing the biochemical fingerprints of unknown strains to those of a set of reference strains of known species. Most strains of Enterococcus faecalis, Enterococcus faecium and Enterococcus hirae were correctly identified using this method. We conclude that the PhenePlate RF system is useful for rapid typing of enterococcal populations, and it is especially useful as a first screening method for ecological studies, when many isolates per sample need to be analysed.  相似文献   
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