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51.
52.
Feline proinsulin was cloned and expressed using a bacterial expression system. It was then purified from inclusion bodies using size exclusion chromatography and further processed including reduction of the protein. Following refolding, proinsulin was purified by reversed-phase high-performance liquid chromatography (RP-HPLC). RP-HPLC and mass spectrometric analysis indicated that the proinsulin contained the correct disulfide bridging pattern. This proinsulin can be used for therapeutic and diagnostic purposes.  相似文献   
53.
A well-saturated genetic linkage map is valuable for fundamental and applied genetic research. Genetic linkage maps of two half-sib diploid banana populations were constructed using allele-specific-polymerase chain reactions (AS-PCRs), diversity array technology (DArT), and simple sequence repeat (SSR) markers. Molecular maps were produced for each parent using the pseudo-testcross mapping strategy. The first maternal map (6142-1, 81 individuals) consisted of 231 markers divided as followed: 121 DArT, 106 SSR and 4 AS-PCR markers in 15 linkage groups (LGs) covering 670?cM. The second maternal map (6142-1-S, 58 individuals) contained a total of 152 markers including 71 DArTs, 79 SSRs, and 2 AS-PCRs mapped to 16 LGs that spanned 698?cM. The combined paternal map (139 individuals) comprised 316 markers (196 DArTs, 117 SSRs and 3 AS-PCRs) distributed over 15 LGs with a total map length of 1,004?cM. While distorted segregation of some markers was observed in all maps, this was much more frequent for the male parent. Homology between maps was assessed using common markers. While there was generally good congruity with regard to marker order across maps, incongruity in other cases may reflect chromosomal rearrangement events such as inversions, translocations, or deletions. The new banana map can provide a better understanding of the Musa genome and could be used for the identification of economically important traits and improvement of breeding strategies.  相似文献   
54.
This study evaluated the in vitro activity of diphenyl diselenide against 19 Pythium insidiosum isolates and the in vivo therapeutic response of rabbits with experimentally induced pythiosis. In vitro: susceptibility tests were performed using the broth macrodilution method in accordance with the CLSI document M38-A2. The criteria for interpretation were as follows: MIC-1 and MIC-2 (inhibition of 90% and 100% of mycelium growth, respectively) and the minimum fungicide concentration (MIC-3). In vivo: twenty rabbits were divided into four groups with five animals each and treated for 40 consecutive days: groups 1 and 2 (experimentally induced pythiosis) were treated with diphenyl diselenide (10mg/kg/day) and canola oil (1 mL/kg/day), respectively; groups 3 and 4 (controls) were treated with canola oil (1 mL/kg/day) and diphenyl diselenide (10mg/kg/day), respectively. Toxicity was evaluated using biochemical and haematological parameters. In vitro susceptibility tests showed that 89.4% of isolates had a MIC-1 ≤ 0.5 μg/mL, 84.2% of isolates had a MIC-2 ≤ 1.0 μg/mL and 94.7% of isolates had a MIC-3 ≤ 2.0 μg/mL. The in vivo assay suggested that this compound has a fungistatic activity, and the biochemical and haematological parameters indicated that there was no renal, hepatic or haematological toxicity. The comparison of the unsaturated iron binding capacity levels between animals with and without pythiosis suggested the involvement of iron metabolism in the pathogenesis of pythiosis. This study demonstrated the absence of detectable toxicity caused by diphenyl diselenide and the in vitro fungicidal and in vivo fungistatic activities of this drug, which makes it an option for future therapeutic approaches in the treatment of pythiosis.  相似文献   
55.
The increase in obesity in people and pets has been phenomenal. As in man, obesity in pets is a risk factor for many diseases including diabetes mellitus. Recently, tissue-specific regulation of glucose metabolism in fat and muscle tissue has been identified as an important factor for insulin sensitivity and it has been hypothesized that glucose uptake into tissues is altered in obesity causing insulin resistance. The purpose of this study was to determine the expression of the glucose transporter proteins GLUT4 and GLUT1 in muscle and fat from lean and obese cats. Seventeen domestic felines were tested in the lean state and again after a 6-month period of ad libitum food intake which led to a significant increase in weight (P<0.0001). Obese cats showed a significantly higher area under the curve (AUC) for glucose, AUC for insulin and a significant decrease in glucose percentage disappearance per min (K-value) (P=0.013, 0.018 and 0.017, respectively) during an intravenous glucose tolerance test, but no change in baseline glucose or glycosylated hemoglobin concentrations. GLUT4 expression was decreased in biopsies of both muscle (P=0.002) and fat (P=0.001) in the obese animals. GLUT4 in muscle and fat significantly and negatively correlated with the insulin AUC (r2=0.36, P=0.004 and r2=0.18, P=0.040, respectively). GLUT1 expression showed no significant change in the obese cats in either tissue. It is concluded that the changes in GLUT4 are early derangements in obesity and occur before glucose intolerance is clinically evident.  相似文献   
56.
Captive and wild African elephants frequently suffer tusk fractures. Several institutions shorten the tusks of captive elephants to reduce fractures and injury as a result of behaviour within enclosures. Fracturing or coronal amputations that expose pulp lead to pain for the elephant. Estimating coronal pulp lengths may thus help to minimise the risk of pulp exposure during amputations. We aimed to determine the length of the pulp beyond the lip margin from an external tusk characteristic. Tusks collected from elephants in Namibia and the Kruger National Park had similar morphological relationships. This statistical property allowed us to correct for missing data in our data sets. Pulp volume and pulp length correlated with tusk circumference at the lip. Even so, the circumference at the lip could not predict the length of the pulp in the crown external to the lip. Our findings suggest that tusks, irrespective of sex or age, amputated further than 300 mm from the lip should not expose pulp.  相似文献   
57.
A dielectric omnidirectional reflector   总被引:3,自引:0,他引:3  
A design criterion that permits truly omnidirectional reflectivity for all polarizations of incident light over a wide selectable range of frequencies was used in fabricating an all-dielectric omnidirectional reflector consisting of multilayer films. The reflector was simply constructed as a stack of nine alternating micrometer-thick layers of polystyrene and tellurium and demonstrates omnidirectional reflection over the wavelength range from 10 to 15 micrometers. Because the omnidirectionality criterion is general, it can be used to design omnidirectional reflectors in many frequency ranges of interest. Potential uses depend on the geometry of the system. For example, coating of an enclosure will result in an optical cavity. A hollow tube will produce a low-loss, broadband waveguide, whereas a planar film could be used as an efficient radiative heat barrier or collector in thermoelectric devices.  相似文献   
58.
Effects of small population size and reduced genetic variation on the viability of wild animal populations remain controversial. During a 35-year study of a remnant population of greater prairie chickens, population size decreased from 2000 individuals in 1962 to fewer than 50 by 1994. Concurrently, both fitness, as measured by fertility and hatching rates of eggs, and genetic diversity declined significantly. Conservation measures initiated in 1992 with translocations of birds from large, genetically diverse populations restored egg viability. Thus, sufficient genetic resources appear to be critical for maintaining populations of greater prairie chickens.  相似文献   
59.
O'Garro  Gore  & Ferguson 《Plant pathology》1999,48(5):588-594
A total of 404 isolates of Xanthomonas campestris pv. vesicatoria , obtained from Capsicum chinense cv. West Indian Red grown in Barbados and Grenada, were differentiated into pathogenic races, and of these, 96 were tested also for selected taxonomic group phenotypes. The response of C. chinense to infection by several X. campestris pv. vesicatoria races and the contribution of races isolated from this cultivar to severity of bacterial spot of bell pepper and tomato were also investigated. P4T2, P5T2 and P6T2 were the predominant races of X. campestris pv. vesicatoria isolated from C. chinense grown in Grenada, whereas nine races (T1, P4, P6, P0T2, P1T2, P4T1, P4T2, P6T1 and P6T2) were isolated in Barbados. Race P4T2 comprised 46.0 and 71.4% of the isolates from Barbados and Grenada, respectively. The 96 isolates, all of which overcame resistance conferred by the gene Bs2 , shared taxonomic group B strain characteristics, including the presence of the β-protein band, positive amylolytic activity and inability to oxidize cis -aconitate. The C. chinense cv. West Indian Red was susceptible only to races of X. campestris pv. vesicatoria that can overcome Bs2 gene resistance. Of six such races identified in Barbados, only P4T1, P4T2 and P6T1 affected bacterial spot-susceptible bell pepper or tomato in the field, and they amounted to only 1.5–2.1% of each sample of isolates from these plant species. Moreover, they were confined to the smallest bacterial spot lesions. Bell pepper was most severely affected by combinations of races T1 with P3T2 and T2 with P0T1, and tomato by race T1 only and combinations of races P0T1 with P0T2 and P1T1 with P1T0, all of which prevailed in the field despite selection against them by C. chinense cv. West Indian Red.  相似文献   
60.
Introduction Rapid development of the river buffalo physical map can be achieved by coupling its development to that of the cattle gene map. Syntenic conservation between cattle and buffalo has been demonstrated, mainly using somatic cell hybrids (de Hondt et al. 1991; El Nahas et al. 1993, 1996, 1998; de Hondt et al. 1997; El Nahta 1996; Oraby et al. 1977), and by using in situ hybridization as reviewed by Iannuzzi (1997). G- and R-banding comparisons between cattle (2n = 60) and river buffalo (2n = 50) chromosomes have revealed a large number of banding homologies between the two species, both at early-metaphase (Gupta and Ray -Chaudhury 1978; Di Berardino et al. 1981) and prometaphase stages (Iannuzzi et al. 1990). Banding homology indicates that the five river buffalo biarmed pairs originate from centric fusion translocation between two of ten homologous cattle autosomes, which is very supportive of the hypothesis that both species have a common ancestor (Wurster and Benirschke 1968). Based on cytological analysis and banding homology between cattle and buffalo chromosomes, the five biarmed chromosomes of the river buffalo BBU1, BBU2, BBU3, BBU4, BBU5 were thought to originate from fusion of cattle chromosome (BTA) 1/25; 2/23; 8/19; 5/28; and 16/29 respectively (Iannuzzi et al. 1990; Report of the Committee for the Standardization of Banded Karyotopes of the River Buffalo 1994). However, the analysis of synteny between molecular markers assigned to different cattle syntenic groups demonstrated that BBU1 results from fusion of BTA 1 and 27 rather than 1 and 25 (El Nahas et al. 1977). This called for expanding the analysis of syntenic relationships between marker loci to confirm the nature of the other biarmed buffalo chromosomes. The purpose of this study is to test synteny between markers in buffalo and to confirm the nature of the biarmed buffalo chromosomes 4 and 5, using marker loci and somatic cell hybrids.  相似文献   
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