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101.
We consider the problem of comparing several nucleic acid sequencesto identify words occurring imperfectly (patterns with no gap)with unusual frequency. Methods for computing, representing,and inspecting interactively the structure of such repeatingmotifs in nucleic acids and more generally any text are described.Multiple sequences are treated as one large concatenate. Ina preprocessing step, a lexical index is created to providerapid string matching for the enumeration of the words matchinga pattern. For given word features (word length, minimal frequency),a sequence profile is displayed. The profile can be inspectedinteractively with on-line algorithms. Applications to the identificationof regulatory elements in DNA regions involved in the controlof gene expression are presented. Our program (DNA-Lexemics)runs on the Macintosh. 相似文献
102.
Dispersal propensity of green leafhoppers was compared between a tropical species, Nephotettix virescens, and a temperate species, N. cincticeps. The flight ability was measured with tethered flight technique under laboratory conditions (25°C, 16L-8D). The pre-flight period was shorter and the flight duration was longer in N. virescens than in N. cincticeps in both sexes. No significant correlations were found between the flight activity and morphometric characters for either of the two species. The results suggested that dispersal propensity of N. virescens is higher than that of N. cincticeps. 相似文献
103.
Sakaba Tomoka Soejima Akiko Fujii Shinji Ikeda Hajime Iwasaki Takaya Saito Hiroaki Suyama Yoshihisa Matsuo Ayumi Kozhevnikov Andrey E. Kozhevnikova Zoya V. Wang Hongfeng Wang Siqi Pak Jae-Hong Fujii Noriyuki 《Journal of plant research》2023,136(4):437-452
Journal of Plant Research - A group of temperate grassland plant species termed the “Mansen elements” occurs in Japan and is widely distributed in the grasslands of continental East... 相似文献
104.
Summary The hybrid produced between a Carbondale haploid strain (-methyl-glucoside rapid fermenter) and a haploid strain (non-fermenter), derived from a hybrid between a homothallic and a heterothallicSaccharomyces, showed an irregular segregation pattern with regard to the fermentation of this sugar.To explain this irregularity, three pairs of alleles,MG
1/mg
1,MG
2/mg
2 andMG
3/mg
3, were assumed to be in quantitative control of the fermetation. Haploid cultures carrying the genotypes (1)mg
1
mg
2
mg
3, (2)MG
1
mg
2
mg
3, (3)mg
1
MG
2
mg
3, (4)mg
1
mg
2
MG
3, (5)MG
1
MG
2
mg
3, (6)MG
1
mg
2
MG
3, (7)mg
1
MG
2
MG
3, and (8)MG
1
MG
2
MG
3, were actually recovered. Strains equipped with: either (1) or (2); either (4) or (6); (3); (5); (7); or (8) are non-fermenters, extremely-slow-fermenters, slow-fermenters, medium-fermenters, semi-rapid-fermenters and rapid-fermenters respectively.The role of these genes in sugar fermentation and the identity or nonidentity of some of these genes with maltose and sucrose genes was discussed.With 2 Figures in the Text 相似文献
105.
The objective of this study was to examine the effect of joint angle on the electromyogram (EMG) and mechanomyogram (MMG) during maximal voluntary contraction (MVC). Eight subjects performed maximal isometric plantar flexor torque productions at varying knee and/or ankle angles. Maximal voluntary torque, EMG, and MMG from the soleus (Sol), medial (MG) and lateral gastrocnemius (LG) muscles were measured at different joint angles. At varying knee angles, the root mean squared (rms) MMG amplitude of the MG and LG increased with knee joint extension from 60 degrees to 180 degrees (full extension) in steps of 30 degrees, whereas that of the Sol was constant. At varying ankle angles, the rms-MMG of all muscles (Sol, MG, and LG) decreased with torque as ankle joint extending from 80 degrees (10 degrees dorsiflexion position) to 120 degrees (30 degrees plantar flexion position) in steps of 10 degrees. In each case, changes in the rms-MMG of the three muscles were almost parallel to those in torque. In contrast, there were no significant differences in the rms-EMG of all muscles among all joint angles. Our data suggest that the MMG amplitudes recorded from individual muscles during MVCs can represent relative torque-angle relationships that cannot be represented by the EMG signals. 相似文献
106.
107.
Shingo Oda Masashi Shibata Toshio Moritani 《Journal of electromyography and kinesiology》1996,6(4):247-252
The purpose of this study was to compare movement-related cortical potentials (MRCPs) associated with different levels of isometric contractions by elbow flexors. Eight healthy, right-handed male subjects participated in this study and performed different levels (10 and 50% of maximal voluntary contraction) of isometric contractions by the right elbow flexors. Electroencephalogram (EEG) signals were recorded from Fz, C3, Cz and C4 of the international 10/20 system. Motor potential (MP) amplitudes (from −200 to approximately −50 ms before force onset) for C3 associated with both force generations was significantly greater (P < 0.01) than those for C4, indicating that contralateral predominance of MRCP was observed in the right arm flexion. In Fz, the potentials of negative slope (NS′) (from −600 to approximately −200 ms) and MPs for 50% MVC were significantly greater than those of 10% MVC. In Cz, the MP associated with 50% MVC revealed a significantly greater (P < 0.05) value than that with 10% MVC. In C3 and C4, the MP associated with 50% MVC tended to be greater than that with 10% MVC, but no statistically significant differences were found. These force-dependent changes in MRCPs imply increased activation of neural circuits involved in motor preparation and initiation. It is therefore suggested that the larger potentials from Fz and Cz for 50% MVC compared with 10% MVC reflect a greater activation of supplementary motor area for the preparation of the larger force generation. 相似文献
108.
109.
Y. Kobayashi Yufuko Takahashi Satoshi Chikayama Motomi Ikeda Nobuhiko Uoshima Shinya Kimura Koji Tanaka Katuya Wada Masaru Ozawa Tatuo Sugano Naoyuki Maruo Motoharu Kondo 《Histochemistry and cell biology》1997,108(2):115-120
We devised a new microfluorometric method for determining the ploidy of megakaryocytes identified immunologically in bone
marrow smears. The smears were immunostained by incubation with mouse monoclonal anti-glycoproteins (GP) IIb antibodies, followed
by fluorescein isothiocyanate-conjugated goat anti-mouse IgG antibodies. They were then stained with 4′,6-diamidino-2-phenylindole
(DAPI). Megakaryocytes were identified by their GPIIb immunofluorescence using a microfluorometer and, after the filters were
changed, their DNA content was assayed by measuring the intensity of DAPI fluorescence. This intensity was shown to be proportional
to the DNA content when the aperture of the objective lens was reduced. We compared these results with those obtained when
megakaryocytes were identified morphologically, using DAPI staining after Wright-Giemsa destaining. In all 12 normal controls,
the ploidy peaks were shown to be 16N by both methods, and the mean ploidy detected by the immunological method was only reduced
0.961 times relative to the estimate from the morphological method. In contrast, in eight myelodysplastic syndrome (MDS) patients,
the ploidy peaks were either 8N or 4N and the mean was reduced by 0.906 times (P=0.018). Thus we could immunologically identify small megakaryocytes which we could not identify morphologically. Therefore,
this method is useful for measuring megakaryocytic ploidy, especially in the pathological megakaryocytes of MDS patients.
Accepted: 29 April 1997 相似文献
110.