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51.
52.

Background  

There are four widely used experimental strains of N. gonorrhoeae, one of which has been sequenced and used as the basis for the construction of a multi-strain, mutli-species pan-neisserial microarray. Although the N. gonorrhoeae population structure is thought to be less diverse than N. meningitidis, there are some recognized gene-complement differences between strains, including the 59 genes of the Gonococcal Genetic Island. In this study we have investigated the three experimental strains that have not been sequenced to determine the extent and nature of their similarities and differences.  相似文献   
53.
Manchego cheese is a high-fat pressed ewe's-milk cheese made in Castilla-La Mancha (Spain) and produced by enzymatic coagulation. The minimum ripening time before marketing required by the Regulatory Board of the Manchego Cheese Appellation of Origin is 60 days.
This paper describes the physicochemical, proteolysis, sensory and texture characteristics of Manchego cheese, and the degree of homogeneity of cheeses made under the Manchego Appellation of Origin. The data gathered in this study indicate that sensory and instrumental analysis are useful tools for detecting changes in Manchego cheese during ripening. These changes were first detected by the instrumental analysis (2 months). The panelists detected differences after 4 months' ripening in all the factories. With physicochemical analysis, on the other hand, longer ripening times (6–8 months) are required before such changes become appreciated.  相似文献   
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Background  

Benchmarking algorithms in structural bioinformatics often involves the construction of datasets of proteins with given sequence and structural properties. The SCOP database is a manually curated structural classification which groups together proteins on the basis of structural similarity. The ASTRAL compendium provides non redundant subsets of SCOP domains on the basis of sequence similarity such that no two domains in a given subset share more than a defined degree of sequence similarity. Taken together these two resources provide a 'ground truth' for assessing structural bioinformatics algorithms. We present a small and easy to use API written in python to enable construction of datasets from these resources.  相似文献   
57.
MEJÍAS, J. A. & VALDÉS, B., 1988. Karyologiepl studies in Sonchus section Madtimi (Asteraceae) from the Iberian Peninmula. Karyological data support the distinction of S. aquatilis Pourret and S. maritimus L. at the specific level. Karyological data and hybridization experiments support the idea that S. × novocaslcllanus Cirujano has been produced by the hybridization of S. crassifolius Pourret ex Willd. and S. maritimus L.  相似文献   
58.
Sequencing of the complete mitochondrial DNA control region from 31 samples of the Eurasian otter, Lutra lutra , enabled us to establish the length and structure of this fragment, as well as to describe, for the first time, the RS3 repetitive region located at the 3' end. In addition, genetic variability of the 5' end was examined in 63 individuals, 57 of which were wild otters from the Iberian Peninsula and six captive reared otters. This analysis resulted in extremely low variability. All the samples from the Iberian Peninsula share a single haplotype, Lut 1, the most common haplotype in Europe. Captive otters showed two haplotypes: Lut 3, which has been described in wild otters from eastern Germany, and Lut 6, an haplotype not described to date. Higher variability was observed in the repetitive RS3 region. The tandem repeat was composed of an array of ten repeat units of 22 bp with differences in the repetitive motifs that differed in the arrays of different specimens. In total, 20 different haplotypes from 31 individuals were found. However, the geographical distribution of these haplotypes did not generate a phylogeographical signal. © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 86 , 397–403.  相似文献   
59.
The potential of the HER2-targeting antibody trastuzumab as a radioimmunoconjugate useful for both imaging and therapy was investigated. Conjugation of trastuzumab with the acyclic bifunctional chelator CHX-A″-DTPA yielded a chelate:protein ratio of 3.4 ± 0.3; the immunoreactivity of the antibody unaffected. Radiolabeling was efficient, routinely yielding a product with high specific activity. Tumor targeting was evaluated in mice bearing subcutaneous (s.c.) xenografts of colorectal, pancreatic, ovarian and prostate carcinomas. High uptake of the radioimmunoconjugate, injected intravenously (i.v.), was observed in each of the models and the highest tumor %ID/g (51.18 ± 13.58) was obtained with the ovarian (SKOV-3) tumor xenograft. Specificity was demonstrated by the absence of uptake of 111In-trastuzumab by melanoma (A375) s.c. xenografts and 111In-HuIgG by s.c. LS-174T xenografts. Minimal uptake of i.v. injected 111In-trastuzumab in normal organs was confirmed in non-tumor-bearing mice. The in vivo behavior of 111In-trastuzumab in mice bearing intraperitoneal (i.p.) LS-174T tumors resulted in a tumor %ID/g of 130.85 ± 273.34 at 24 h. Visualization of tumor, s.c. and i.p. xenografts was achieved by γ-scintigraphy and PET imaging. Blood pool was evident as expected but cleared over time. The blood pharmacokinetics of i.v. and i.p. injected 111In-trastuzumab was determined in mice with and without tumors. The data from these in vitro and in vivo studies supported advancement of radiolabeled trastuzumab into two clinical studies, a Phase 0 imaging study in the Molecular Imaging Program of the National Cancer Institute and a Phase 1 radioimmunotherapy study at the University of Alabama.Key words: monoclonal antibody, HER2, trastuzumab, radioimmunodiagnosis, radioimmunotherapy  相似文献   
60.
In low-phosphorus (P) marine systems, phytoplankton replace membrane phospholipids with non-phosphorus lipids, but it is not known how rapidly this substitution occurs. Here, when cells of the model diatom Thalassiosira pseudonana were transferred from P-replete medium to P-free medium, the phospholipid content of the cells rapidly declined within 48 h from 45±0.9 to 21±4.5% of the total membrane lipids; the difference was made up by non-phosphorus lipids. Conversely, when P-limited T. pseudonana were resupplied with P, cells reduced the percentage of their total membrane lipids contributed by a non-phosphorus lipid from 43±1.5 to 7.3±0.9% within 24 h, whereas the contribution by phospholipids rose from 2.2±0.1 to 44±3%. This dynamic phospholipid reservoir contained sufficient P to synthesize multiple haploid genomes, suggesting that phospholipid turnover could be an important P source for cells. Field observations of phytoplankton lipid content may thus reflect short-term changes in P supply and cellular physiology, rather than simply long-term adjustment to the environment.  相似文献   
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