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1.
The rheophilic hillstream loaches (Balitoridae) of South and Southeast Asia possess a range of pelvic girdle morphologies, which may be attributed to adaptations for locomotion against rapidly flowing water. Specifically, the connectivity of the pelvic plate (basipterygium) to the vertebral column via a sacral rib, and the relative size and shape of the sacral rib, fall within a spectrum of three discrete morphotypes: long, narrow rib that meets the basipterygium; thicker, slightly curved rib meeting the basipterygium; and robust crested rib interlocking with the basipterygium. Species in this third category with more robust sacral rib connections between the basipterygium and vertebral column are capable of walking out of water with a tetrapod-like lateral-sequence, diagonal-couplet gait. This behavior has not been observed in species lacking direct skeletal connection between the vertebrae and the pelvis. The phylogenetic positions of the morphotypes were visualized by matching the morphological features onto a novel hypothesis of relationships for the family Balitoridae. The morphotypes determined through skeletal morphology were correlated with patterns observed in the pelvic muscle morphology of these fishes. Transitions towards increasingly robust pelvic girdle attachment were coincident with a more anterior origin on the basipterygium and more lateral insertion of the muscles on the fin rays, along with a reduction of the superficial abductors and adductors with more posterior insertions. These modifications are expected to provide a mechanical advantage for generating force against the ground. Inclusion of the enigmatic cave-adapted balitorid Cryptotora thamicola into the most data-rich balitorid phylogeny reveals its closest relatives, providing insight into the origin of the skeletal connection between the axial skeleton and basipterygium.  相似文献   
2.
Mitogen-activated protein (MAP) kinases mediate cellular responses to a wide variety of stimuli. Activation of a MAP kinase occurs after phosphorylation by an upstream dual-specificity protein kinase, known as a MAP kinase kinase or MEK. The Arabidopsis thaliana genome encodes 10 MEKs but few of these have been shown directly to activate any of the 20 Arabidopsis MAP kinases. We show here that functional complementation of the cell lysis phenotype of a mutant yeast strain depends on the co-expression of the Arabidopsis MEK AtMKK6 and the MAP kinase AtMPK13. The kinase activity of AtMPK13 is stimulated in the presence of AtMKK6 in yeast cells. RT-PCR analysis showed the co-expression of these two genes in diverse plant tissues. These data show that AtMKK6 can functionally activate the MAP kinase AtMPK13.  相似文献   
3.
This study aims to find the optimal medium and conditions for polylactic acid (PLA)-degrading enzyme production by Amycolatopsis sp. SCM_MK2-4. Screening of the most effective components in the enzyme production medium by Plackett–Burman design revealed that the silk cocoon and PLA film were the most significant variables enhancing the PLA-degrading enzyme production. After an response surface methodology, a maximum amount of PLA-degrading enzyme activity at 0.74?U?mL?1 was predicted and successfully validated at 95% after 0.39% (w/v) silk cocoon and 1.62% (w/v) PLA film were applied to the basal medium. The optimal initial pH value, temperature, and inoculum size were evaluated by a method considering one-factor-at-a-time. The values were recorded at an initial pH in the range of 7.5–9.0, a temperature of 30–32°C, and an inoculum size of 4–10%. The highest activity of approximately 0.95?U?mL?1 was achieved after 4 days of cultivation using the optimized medium and under optimized conditions in a shake flask. Upscaling to the use of a 3-L stirred tank fermenter was found to be successful with a PLA-degrading activity of 5.53?U?mL?1; which represents a 51-fold increase in the activity compared with that obtained from the nonoptimized medium and conditions in the shake flask.  相似文献   
4.
5.
The microbiota of lactic acid bacteria (LAB) in thirty-five samples of Miang, a traditional fermented tea leaf product, collected from twenty-two different regions of eight provinces in upper northern Thailand was revealed through the culture-dependent technique. A total of 311 presumptive LAB strains were isolated and subjected to clustering analysis based on repetitive genomic element-PCR (rep-PCR) fingerprinting profiles. The majority of the strains belonged to the Lactobacillus genera with an overwhelming predominance of the Lb. plantarum group. Further studies of species-specific PCR showed that 201 of 252 isolates in the Lb. plantarum group were Lb. plantarum which were thus considered as the predominant LAB in Miang, while the other 51 isolates belonged to Lb. pentosus. In contrast to Lb. plantarum, there is a lack of information on the tannase gene and the tea tannin-tolerant ability of Lb. pentosus. Of the 51 Lb. pentosus isolates, 33 were found to harbor the genes encoding tannase and shared 93-99% amino acid identity with tannase obtained from Lb. pentosus ATCC 8041T. Among 33 tannase gene-positive isolates, 23 isolates exhibited high tannin- tolerant capabilities when cultivated on de Man Rogosa and Sharpe agar-containing bromocresol purple (0.02 g/L, MRS-BCP) supplemented with 20% (v/v) crude tea extract, which corresponded to 2.5% (w/v) tannins. These Lb. pentosus isolates with high tannin-tolerant capacity are expected to be the high potential strains for functional tannase production involved in Miang fermentation as they will bring about certain benefits and could be used to improve the fermentation of tea products.  相似文献   
6.
Using immunohistochemistry, the study demonstrates substances of the innate immunity in the skin of the Malayan pangolin (Manis javanica), referring mainly to the epidermis. The results obtained showed clear reaction differences between the dorsolateral body region with its strong cover of hard horny scales and the abdominal body part with a thick soft stratum corneum and a dense cover of fine hairs. Regarding pathogen recognition receptors, positive reactions for Toll-like receptors were generally weak for TLR2, in contrast to TLR4, that exhibited strong reactions in the epidermis of both body regions, with increasing staining intensities towards the stratum corneum; ß-glucan receptors showed positive reactions only for l-ficolin and mannose-binding lectin, but not for dectin-1, and only at the abdomen. A generally positive staining for both body regions was obtained for all cationic antimicrobial peptides tested, whereby cathelicidin exhibited strong reaction intensities in all epidermal layers, ß-defensin 2 staining was often limited to the stratum basale and the stratum spinosum, and positive reactions for ß-defensin 3 appeared distinctly only in the epidermis of the abdomen; for these peptides, positive reaction staining could also be found in the outer epithelial root sheath of hair follicles, their glandular annexes, and free cells of the dermis. Lysozyme was found in the vital epidermis of both body regions studied, with strong staining limited to the dorsum; strong reactions were also visible in the hair follicles.  相似文献   
7.
The riverine species, Henicorhynchus siamensis (Sauvage 1881), is an important source of protein and an economical fish for the rural population of inland Indochina. Investigated in the present study were the reproductive feeding aspects and growth of H. siamensis living in a lake system. The gonadosomatic index peaked in August, which was delayed compared to river fish, and individuals took 1.5 years to attain the length of 50% maturity (about 200 mm). Stomach contents were dominated by phytoplankton and showed considerable seasonal variation. Asymptotic length of H. siamensis was 264.2 mm, with a 0.75 year?1 growth coefficient and slower growth during the winter. The role of the flood pulse as a major influence on the life history of the fish is also discussed.  相似文献   
8.
A highly stable and productive hairy root culture from peanut cultivar Tainan9 (T9-K599) was established using Agrobacterium rhizogenes strain K599 (NCPPB 2659)-mediated transformation. Valuable phenolic compounds with antioxidant activity and stilbene compounds were produced and secreted into the culture medium after elicitation with 100 µM methyl jasmonate (MeJA) and 6.87 mM cyclodextrin (CD). The antioxidant activity of the culture medium was increased to the highest Trolox equivalent antioxidant capacity (TEAC) value (28.30?±?2.70 mM Trolox/g DW) in the group treated with CD. The group co-treated with MeJA and CD exhibited the highest phenolic content, with a gallic acid equivalent (GAE) value of 10.80?±?1.00 µg gallic acid/g DW. The CuZn-SOD (CuZn superoxide dismutase) and APX (ascorbate peroxidase) antioxidant enzyme gene were up-regulated in the treatment with CD alone while the CuZn-SOD, GPX (glutathione peroxidase) and APX gene expression were down-regulated in the co-treatment with MeJA plus CD. The stilbene compounds resveratrol, trans-arachidin-1 and trans-arachidin-3 were detected by analysing the culture medium treated with CD alone and after co-treatment with MeJA and CD via HPLC. The LC-MS/MS results confirmed the presence of resveratrol, trans-arachidin-1, trans-arachidin-3, 4-Isopentadienyl-3,5,3′,4′-tetrahydroxystilbene (IPP), trans-3′-Isopentadienyl-3,5,4′-trihydroxystilbene (IPD) and arahypin-7. The results indicate that elicited peanut hairy roots can produce beneficial stilbene compounds that have antioxidant properties and anti-inflammatory activity. This peanut hairy root system could be applied as an experimental model to enhance the production of stilbene and other polyphenolic bioactive compounds.  相似文献   
9.
Profilin is a small actin-binding protein and is expressed at high levels in mature pollen where it is thought to regulate actin filament dynamics upon pollen germination and tube growth. The majority of identified plant profilins contain a MAP kinase phosphorylation motif, P-X-T-P, and a MAP kinase interaction motif (KIM). In in vitro kinase assays, the tobacco MAP kinases p45(Ntf4) and SIPK, when activated by the tobacco MAP kinase kinase NtMEK2, can phosphorylate the tobacco profilin NtProf2. Mutagenesis of the threonine residue in this motif identified it as the site of MAP kinase phosphorylation. Fractionation of tobacco pollen extracts showed that p45(Ntf4) is found exclusively in the high-speed pellet fraction while SIPK and profilin are predominantly cytosolic. These data identify one of the first substrates to be directly phosphorylated by MAP kinases in plants.  相似文献   
10.
The present study demonstrates the effectiveness of X-ray radiation in strain improvement for defective lipase production by Bacillus sp. MR10 for further application in the fermentative production of manno-oligosaccharides (MOS) from agricultural by-product, defatted copra meal (DCM). The mutants obtained were screened based on their defective lipase activity together with their β-mannanase production performance. Among 10 selected mutants, the strain M7 was the highest promising mutant regarding the smallest lipase activity (0.05 U/ml) and the retained β-mannanase activity similar to the parental strain (22 U/ml) were detected. The mutant M7 effectively hydrolyzed DCM to MOS with low-degree of polymerization (DP) oligomers including mannotriose (M3), mannotetraose (M4), and mannopentose (M5) as the main products. Although the pattern of DCM hydrolysis products of mutant M7 was distinctly different from wild type, the biochemical and catalytic properties of purified β-mannanase of mutant were similar to those of wild type. Both purified β-mannanases with apparent molecular mass of 38?kDa displayed optimal activity at pH 5–7 and 45–55°C. Co2+ and Hg2+ nearly completely inhibited activities of both enzymes, whereas Ba2+, Fe3+, and 2-mercaptoethanol obviously activated enzyme activities. Both enzymes showed high specificity for locust bean gum, konjac mannan, DCM, and guar gum. Thus, the mutant M7 has a potential for commercial production of high-quality MOS from low-cost DCM for further application in the feed industry.  相似文献   
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