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1.
We have developed a new mini-procedure for isolation of total cellular DNA from date palm (Phoenix dactylifera L.). The procedure, which does not use liquid nitrogen, has proved useful due to temporary disruptions in supplies of liquid nitrogen that occur in countries where date palm trees are cultivated. DNA suitable for RFLP and PCR analyses is obtained.  相似文献   
2.
AimThe aim was to provide a dosimetric comparison between IMRT and RapidArc treatment plans with RPI index with simultaneous comparison of the treatment delivery time.BackgroundIMRT and RapidArc provide highly conformal dose distribution with good sparing of normal tissues. However, a complex spatial dosimetry of IMRT and RapidArc plans hampers the evaluation and comparison between plans calculated for the two modalities. RPI was used in this paper for treatment plan comparisons. The duration of the therapeutic session in RapidArc is reported to be shorter in comparison to therapeutic time of the other dynamic techniques. For this reasons, total treatment delivery time in both techniques was compared and discussed.Materials and methods15 patients with prostate carcinoma were randomly selected for the analysis. Two competitive treatment plans using respectively the IMRT and RapidArc techniques were computed for each patient in Eclipse planning system v. 8.6.15. RPIwin® application was used for RPI calculations for each treatment plan.Additionally, total treatment time was compared between IMRT and RapidArc plans. Total treatment time was a sum of monitor units (MU) for each treated field.ResultsThe mean values of the RPI indices were insignificantly higher for IMRT plans in comparison to rotational therapy. Comparison of the mean numbers of monitor units confirmed that the use of rotational technique instead of conventional static field IMRT can significantly reduce the treatment time.ConclusionAnalysis presented in this paper, demonstrated that RapidArc can compete with the IMRT technique in the field of treatment plan dosimetry reducing the time required for dose delivery.  相似文献   
3.
  1. As a highly endangered species, the giant panda (panda) has attracted significant attention in the past decades. Considerable efforts have been put on panda conservation and reproduction, offering the promising outcome of maintaining the population size of pandas. To evaluate the effectiveness of conservation and management strategies, recognizing individual pandas is critical. However, it remains a challenging task because the existing methods, such as traditional tracking method, discrimination method based on footprint identification, and molecular biology method, are invasive, inaccurate, expensive, or challenging to perform. The advances of imaging technologies have led to the wide applications of digital images and videos in panda conservation and management, which makes it possible for individual panda recognition in a noninvasive manner by using image‐based panda face recognition method.
  2. In recent years, deep learning has achieved great success in the field of computer vision and pattern recognition. For panda face recognition, a fully automatic deep learning algorithm which consists of a sequence of deep neural networks (DNNs) used for panda face detection, segmentation, alignment, and identity prediction is developed in this study. To develop and evaluate the algorithm, the largest panda image dataset containing 6,441 images from 218 different pandas, which is 39.78% of captive pandas in the world, is established.
  3. The algorithm achieved 96.27% accuracy in panda recognition and 100% accuracy in detection.
  4. This study shows that panda faces can be used for panda recognition. It enables the use of the cameras installed in their habitat for monitoring their population and behavior. This noninvasive approach is much more cost‐effective than the approaches used in the previous panda surveys.
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4.
Thymidylate synthetase from mouse leukemic L1210 cells was purified to electrophoretic homogeneity with 70% yield as a result of an affinity chromatography procedure based on reversible deoxyuridylate-dependent binding of the enzyme to a stable biospecific adsorbent, 10-formyl-5,8-dideazafolate, immobilized on aminoethyl-Sepharose. The presence of neutral detergents, Triton X-100, or Nonidet P40 stabilized thymidylate synthetase during purification. Analytical electrophoresis of the enzyme treated with an excess of 5-fluorodeoxyuridylate and 5,10-methylenetetrahydrofolate showed the presence of two forms of thymidylate synthetase--5-fluorodeoxyuridylate.5,10-methylenetetrahydrofolate complex, indicating that there are two binding sites for 5-fluorodeoxyuridylate present on the enzyme molecule. Molecular weight of native thymidylate synthetase was found to be 75,000, whereas that for the monomer was 38,500.  相似文献   
5.
Summary Gonyaulax polyedra was subjected to a cold treatment of 18 h at 10 °C leading to arrhythmicity. Subsequently, the circadian rhythm of bioluminescence was investigated at the permissive temperature of 20 °C. 1-h pulses of 10 M cycloheximide or 2 M anisomycin, when given after the temperature step-up, resulted only in a very weak resetting of the circadian oscillator, in marked contrast to the behaviour of cells kept continuously in oscillatory conditions at 20 °C. The extremely reduced sensitivity to 80 S inhibition was characteristic for the first cycle after the temperature step-up, whereas cells treated with cycloheximide in the second cycle after re-initiation of rhythmicity showed a gradual recovery of resettability, though the phase response curve was still atypical; treatment in the 3rd cycle after step-up led to a relatively normal phase response curve. The observed insensitivity in the 1st cycle was neither a consequence of insufficient drug action, nor of a transient non-oscillatory behaviour after temperature step-up. Already in the first hours after transfer to 20 °C, 80 S translation was strongly suppressed by cycloheximide, and the cells were also efficiently reset by changes of the light-dark zeitgeber. Resettability of the circadian oscillator by 80 S inhibitors is, therefore, conditional.Abbreviations Ani anisomycin - Chx cycloheximide - CT circadian time - LD light-dark cycle - LL constant light - TCA trichloroacetic acid This work was supported by the Deutsche Forschungsgemeinschaft  相似文献   
6.
125I-Wheat germ agglutinin (WGA) binding parameters of human urothelial cell lines of different grades of transformation (TGrll and TGrlll) were compared. The values of association constant (Ka) and the number of binding sites/cell for HCV29 (TGrll) cell line were about 3×106M–1 and over 4×107, respectively. Two TGrlll cell lines, HCV29T and Hu549 revealed lower values for Ka, and considerably higher numbers of binding sites/cell (about 3×108 and 2×108, respectively). Binding of125I-WGA to total cellular proteins resolved by SDS-PAGE and transferred to nitrocellulose showed multiple diffused bands in the range of 58–180 kDa. Some of these bands were characteristic for TGrll cells (124 kDa) or TGrlll cells (135 and 148 kDa).Abbreviations TGr transformation grade - WGA wheat germ agglutinin - sWGA succinylated wheat germ agglutinin - GlcNAc N-acetyl-d-glucosamine - BSA bovine serum albumin - SDS-PAGE sodium dodecyl sulphate polyacrylamide gel electrophoresis  相似文献   
7.
Summary The expression of MHC class II determinants Ia.7 (detected by cross reactive mouse anti-Iak antibody) and HLA-DR on monocytes (MO) of gastric and colorectal cancer patients was examined. An increased proportion of MO bearing the Ia.7 determinant was found, while the number of MO expressing DR was not elevated. In gastric cancer patients the increased expression of the Ia.7 determinant was most pronounced in advanced cancer (stage IVA and IVB). The increased expression of this determinant was related to the presence of the tumour as the number of MO expressing Ia.7 decreased 6 months following surgical resection of the tumour. Further, the increased expression of Ia.7 on MO correlated with the tumour infiltration of the serosa. The Ia.7 determinants were mainly expressed on MO which also expressed the receptor for the Fc part of immunoglobulin. Immunostaining in cellular infiltrates surrounding the tumour revealed that Ia.7+ macrophages (MØ) were more numerous than in normal gastric mucosa and severe chronic gastritis and were mostly present in close proximity to tumour cells, while DR+ MØ were mainly localized within the stromal tissue of the tumour and their number was not increased in cancer infiltrates. These observations indicate that the Ia.7+ subpopulation of MØ may be involved in the anti-tumour response of the host.  相似文献   
8.
Summary Restriction fragment length polymorphism of the wheat nuclear ribosomal DNA has been studied in several steps of a breeding scheme, including parental genotypes, F1 hybrid, F9 generation, and anther-derived doubled haploid lines obtained from F9. Ribosomal DNA represents a suitable molecular marker in following segregation and possible divergency from expected homozygosity after haploidization of an androgenetic process. It has been shown to undergo variations among the first cycle-doubled haploid lines in the relative amount of two different sizes of ribosomal DNA repeat units. The specificity and peculiar properties of the plant system used allowed us to assign an intrachromosomal location (short arm of the chromosomes 1B, 1R or 6B) to several ribosomal DNA repeat units that differ by the length of their nontranscribed spacer region.  相似文献   
9.
The complete primary structures of toxin II-14 from the Mexican scorpion Centruroides noxius Hoffmann and toxin gamma from the Brazilian scorpion Tityus serrulatus Lutz and Mello have been determined. Cleavage of toxin gamma after Met-6 with CNBr produced the 55-residue peptide 7-61, which maintained the four disulphide bonds but was not toxic to mice at a dose 3 times the lethal dose of native toxin gamma. Pairwise comparison by metric analysis of segment 1-50 of toxin gamma and the corresponding segments from two other South American scorpion toxins, five North American scorpion toxins, nine North African scorpion toxins and one Central Asian scorpion toxin showed that the three Brazilian toxins are intermediate between the North American and North African toxins. This result is consistent with the hypothesis that the South American and African continents were joined by a land connection in the distant past.  相似文献   
10.
Two methods are described for locating the O-(carboxymethyl) groups in O-(carboxymethyl)guar. In Method I, O-(carboxymethyl)guar was depolymerized by methanolysis, the O-(carboxymethyl) groups were reduced, and the mixture of methyl glycosides and O-(2-hydroxyethyl)-substituted methyl glycosides was converted into a mixture of per-O-acetylated alditols and partially O-(2-acetoxyethyl)ated, partially O-acetylated alditols. Analysis of these alditols by gas-liquid chromatography-mass spectrometry allowed the positions of substitution of the O-(carboxymethyl) groups on the galactosyl groups and mannosyl residues to be determined. However, this method did not distinguish between O-(carboxymethyl) substitution on 4-linked and 4,6-linked mannosyl residues. This limitation was overcome by the more-detailed analysis provided by Method II, in which O-(carboxymethyl)guar was carboxyl-reduced, the product methylated, the glycosyl residues hydrolyzed, the sugars reduced, and the alditols acetylated to yield a mixture of partially O-acetylated, partially O-methylated alditols and partially O-acetylated, partially O-(2-methoxyethyl)ated, partially O-methylated alditols. These derivatives, when separated and quantitated by g.l.c., and identified by g.l.c.-m.s., gave a quantitative measure of every type of carboxymethyl substitution in guar.  相似文献   
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