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Two new species of the genus Hymenaphorura are described from the Maoershan National Forest Park, northeast China: H. maoerensis sp. nov. and H. minuta sp. nov. The former seems to be especially similar to H. granulata, H. sensitiva, H. superba and H. nearctica, but differs by a combination of the following characters: 1 submedial chaeta on Th. I tergum, second external papilla in AIIIO simple, inner tooth on unguis absent, chaeta C3 of proximal whorl of tibiotarsi absent, chaetae p2 and p3 on Abd. I—III of roughly subequal in length while S-chaeta weakly developed. H. minuta sp. nov. belongs to a group of species showing 9 chaetae in the distal whorl of the tibiotarsi, but it can easily be distinguished from the other members of the group by the dorsal pso formula.
Thalassaphorura is reported for the first time in Northwest China. Four members of the genus were recorded, including three new species (T. qinlingensis sp. nov., T. bisetosa sp. nov., T. petiti sp. nov.) and one known species (T. pornorskii Sun, Chen et Deharveng, 2010). All-three new species possess modified chaetae (male ventral organ) on ventral tube - a character rarely present in congeners. Apart from this, T. bisetosa sp. nov. is characterized by an unique feature - only two small dental chaetae on the furcal area, which differentiates it from all other known Thalassaphorura.
The diagnosis of Bionychiurus Pomorski, 1996 is updated and a identification key to the world species of the genus is given. A new species, B. changbaiensis sp. nov., as the first Chinese species of the genus, is described from Northeast China. The new species is diagnosed by pso formulae as 32/133/33343 dorsally and 11/000/01120 ventrally, psx present on subcoxa 1 of legs I, II and III as 1,1 and 1 respectively, PAO composed with 22-26 granulated vesicles, Th. I with 9-10+9-10 chaetae dorsally, chaetae on subcoxa 1 of legs I-III as 5/6/6, unguiculus 0.8 times as long as inner edge of unguis and anal spines as long as inner edge of hind unguis.
Two new species of Sensillonychiurus, are described from Changbai Mountains, northeastern China: S. reducta sp. nov. and S. pseudoreducta sp. nov. Both these species are very similar to each other, sharing such characters as a reduced unguiculus, 4 papillae and 3 guard chaetae on the Ant. III sensory organ, the AC type of labium, 5+5 chaetae on Th. I tergum, 9 distal tibiotarsal chaetae, as well as the absence of anal spines. Yet they can be differentiated by the presence vs. absence of pso on Th. I tergum, of chaetae p2 on Th. II tergum, and of chaetae b2 on the upper anal valve, respectively, as well as by the number of dorsal S-chaetae, of sublobal hair on the maxillary palp, of p-row chaetae on Abd. IV tergum.
Ship motion is an important factor affecting on the safety of ski-jump take-off. The simplified frigate ship SFS1 was numerically simulated, and the results were compared with the experimental data, the feasibility of the calculation method was verified; Meshless method and WALE turbulence model were used to simulate the process of aircraft skijump take-off, aerodynamic characteristics under different rolling conditions during the aircraft ski-jump take-off process were presented. The results showed that: the influence of ship rolling motion on lift coefficient, drag coefficient and pitching moment was small, side force and rolling moment were greatly affected by rolling motion; the region of downwash with the maximum speed was about 10 m from the bow; the safety of ski-jump take-off was greatly affected when aircraft was close to the bow within 20 m
The new species Agrapkorura xuae sp. nov. is described from continental Ecuador, the first onychiurid species record in this region. The new species is most similar to A. gambiarius (Murphy, 1965) from West Africa, but they can be separated easily by the number and length of p-chaetae between two inner posterior pso on the head, the number of chaetae on Th. I tergum, the presence of the male ventral organ and the ratio of the empodial appendage/unguis. A key to the world known species is provided. The list of all known species from continental Ecuador is presented.
This study aimed to assess whether nicotine prevented glutamate neurotoxicity in PC12 cells, and to identify the molecular mechanisms of any effects. The results showed that glutamate neurotoxicity in PC12 cells could be prevented by treatment with nicotine at concentrations of 10 nmol.l-1-1 mmol.l-1. This effect was in turn found to be inhibited by the application of the nicotinic acetylcholine receptor (nAChR) antagonist mecamylamine. Nicotine significantly decreased the basal level of intracellular free Ca2+ and enhanced the buffering action on Ca2+ overload induced by high concentrations of glutamate (5 mmol.l-1). In addition, nicotine treatment up-regulated the mRNA and protein expression of apoptosis-related factors including bcl-2 mRNA and protein, but down-regulated the expression of bax mRNA and protein. It is concluded that the protective effects of nicotine against the neurotoxicity induced by glutamate are mediated by nAChRs, due to the increased buffering action on Ca2+ and the modulation of apoptotic processes.
An efficient plant regeneration system for Pinellia ternata (Thunb) Breit, an important wild Chinese herb, was established. The investigated factors influencing callus induction and plant regeneration included sterilizing agents, explant type, culture medium, and combinations of plant growth regulators in the medium. Ten min treatment of explants with 0.1% HgCl2 was more suitable for sterilization of tuber explants than NaCIO and H2O2. Tubers as explants were superior to leaves and petioles, and MS medium was better than N6 and White’s media. It was found that 9.1 µM 2,4-dichlorophenoxyacetic acid (2,4-D) plus 4.4 µM 6-benzyladenine (BA) in the medium was the best hormone combination for promoting callus induction. The highest shoot regeneration frequency (99%) was achieved from callus cultured on MS medium supplemented with 9.3 µM kinetin (KN) and 2.3 µM 2,4-D. The rooted shoots were successfully transplanted in soil, with over 95% survival. Establishment of an efficient plant regeneration procedure provides a basis for rapid in vitro propagation of P. ternata, which is in great demand in China, and represents an excellent tool for further work on its genetic manipulation.
The accuracy of quantitative real-time PCR (qRT-PCR) depends on the stability of the reference gene used for normalization. In heading Chinese cabbage (Brassica rapa L. ssp. pekinensis), the most stable reference genes for qRT-PCR during flower bud development have not been elucidated. In this study, the statistical software geNorm was used to test eight candidate reference genes during flower bud development in male sterile (Ms) and fertile (Mf) plants. The result revealed that the stability order was Tub/GAPDH > Cyp > EF1a > U34559 > BrTip41 > Apr > 18S rRNA, Tub and GAPDH were the most stable genes [average expression stability (M) 0.614], and the combined use of six reference genes [pairwise variation (V) 0.15] was suggested to be the optimal reference gene for qRT-PCR during flower bud development. Furthermore, the expressions of BcPME31 during flower bud development normalized with the combined use of six reference genes and with GAPDH or Tub alone were compared; the various results also suggested that selection of the optimal reference gene was necessary for gene expression analysis.
Jasmine [Jasminum sambac (L.) Aiton] growth and development is affected by long-term shade. To determine the effects of short-term shade on jasmine physiology, the contents of soluble proteins, malondialdehyde (MDA) and antioxidative enzymes were comparatively investigated during 24 h (short-term, ST) and 7 days (medium-term, MT) of varying light regimes. The results showed that the protein content exhibited two peaks under ST treatment, and shade postponed the first peak 2 h later than full light. On the whole, protein synthesis was reduced by ST shade and induced by MT shade, whereas MDA content decreased during all shade treatments. Under ST shade, superoxide dismutase (SOD), peroxidase (POD) and ascorbate peroxidase (APX) activities were enhanced, but catalase (CAT) activity was repressed by limited irradiances. However, the antioxidant enzymes responded differently—SOD activity increased after 2 h of shading and then kept on a high level, whereas POD, APX and CAT activities increased mainly during the first hour and deceased subsequently. Under MT shade, these antioxidative enzymes responded differently to varying light irradiances, too. In general, POD and CAT activities were repressed, SOD activity was induced by weak (50% irradiance) shade and reduced by moderate (20% irradiance) and severe (5% irradiance) shade. APX activity was rather more complicated and irregularly responded to different degrees and durations of shade, meaning it might not be the main enzyme to remove ROS in jasmine plants under shading condition. The increase protein content with prolonged shade represents the sound adaptive ability of jasmine plants to restricted irradiances. At the same time, rapid changes in proteins and antioxidants reflect the efficient metabolic apparatus of the plant in response to shade. Therefore, the jasmine cultivar is shade tolerant. Furthermore, shade could help the plants protect themselves from full light, and some degrees of shade were beneficial to their antioxidant system. However, severe shade (5% of irradiance) is only suggested for a few hours to protect the plants at solar noon. If the plants are continuously shaded for 3–7 days, weak (20%) to moderate (50%) level of irradiance should be applied.
Soil dust is one of the sources of PM₂.₅, and most soil dust is derived from bare soil. Our laboratory experiment was conducted to explore the effects of different mulching materials, including cobblestones (CS), green waste (GW), pine bark (PB), and organic mulching mats (OMM) on reducing the generation of soil dust from bare soil by different wind speeds near the ground (2 m/s, 4 m/s, 7 m/s, 9 m/s, and 12 m/s). The results showed that all 4 mulching materials reduced the generation of atmospheric soil dust. Both GW and OMM had the best effect at reducing dust generation when the wind speed near the ground ≤4 m/s, and OMM had the best effect when wind speed was >4 m/s. The mulching materials GW and PB could be completely blown away when the wind speed near the ground reached 7 m/s and 9 m/s, respectively. It appears that OMM is the best mulching material for covering bare soil in Beijing.
Polima (pol) cytoplasmic male sterility (CMS) is reported to be regulated by orf224, but the molecular mechanisms of CMS are less known. In previous research, CMS7311 of heading Chinese cabbage (Brassica campestris L.ssp. pekinensis) was successfully generated from a pol-like CMS, named 77A. To further understand the molecular mechanisms of this male sterility, cDNA-AFLP and qRT-PCR were used to identify genes differentially expressed during flower bud development between cytoplasmic male-sterile plant (Ms) and male-fertile plant (Mf) derived from the hybrid of CMS7311 and a restorer (Rf). Thirty-two transcripts of different fragments (TDFs) of over 80 bp in length were identified using cDNA-AFLP. Among them, ten TDFs were found expressing in Ms bud, and the others expressing in Mf bud. Gene ontology analysis revealed that these genes were involved in stress response, synthesis and metabolism of fatty acid, cell reconstruction, etc. Further, five genes closely related to male sterile were selected and their expression during the flower bud development of Ms and Mf line were investigated by qRT-PCR. Three genes, BcGRP17, BcMS2, and BcPME31, which were necessary for normal male organ development, showed significantly lower expressions in Ms bud; two genes, BcROPGEF8 and BcTNL3, were induced with significantly higher expression in Ms bud by unknown stress and involved in the formation of male sterility. Further work will be focused on cloning these genes and identifying their functions in the male-sterile process of heading Chinese cabbage CMS7311.
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