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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.
In ovarian follicles of the adult house musk shrew, Suncus murinus, glycoconjugates have been studied by means of light- and electron-microscopic histochemistry. The results obtained are that: (1) glycoconjugates of the zona pellucida of oocytes are provided with vicinal diol and acidic groupings, and sialic acid-galactose dimer, alpha-D-mannose, alpha-D-glucose, beta-D-galactose, N-acetyl-D-glucosamine and alpha-L-fucose residues; (2) glycoconjugates of the intercellular matrix of the granulosa and theca folliculi are comparable in histochemical properties to those of the zona pellucida, except for the relatively smaller amount of vicinal diol and acidic groupings, and (3) the zona pellucida can be divided into outer and inner layers by the binding degrees of the lectins used. The possible histophysiological significances of all these glycoconjugates are discussed with special reference to the particular ovarian follicular structures.  相似文献   
5.
6.
Using immunohistochemistry, the study demonstrates the distribution of keratins (pankeratin with CK1-8, 10, 14-16, 19; keratins CK1, 5, 6, 9, 10; hair keratins AE13, AE14) in the epidermis of the Malayan pangolin (Manis javanica). A varying reaction spectrum was observed for pan-keratin, with body region-dependent negative to very strong reaction intensities. The dorsolateral epidermis exhibited positive reactions only in its vital layers, whereas the abdominal epidermis showed strong positive reactions in the soft two outer strata. The single acidic and basic-to-neutral (cyto)keratins produced clear variations compared to the pan-keratin tinging. For example, CK1 appeared in all epidermal layers of both body regions, except for the ventral stratum corneum, whereas CK5, 6, 9, 10 were restricted to the soft ventral epidermis. Here, distinctly positive reactions were confined to the stratum granulosum, except for CK6 that appeared in the soft stratum corneum. A different staining pattern was obvious for the hair keratins, i.e., positive reactions of AE13 concentrated only in the granular layer of the dorsal epidermis. In the abdominal epidermis, remarkable tinging for AE14 was visible in the stratum basale, decreasing toward the corneal layer, but was also found in the outer root sheath cells of the hair follicles in the ventral body part. Our findings are discussed related to the evolution of the horny dorsal scales of the pangolin, which may have started from the tail root, projecting forward to the head.Key words: keratinisation, epidermis, scale evolution, Malayan pangolin, immunohistochemistry  相似文献   
7.
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   
8.
Summary In the colonic epithelium of the chicken, glycoconjugates have been studied by means of selected histochemical methods of light and electron microscopy. According to the results obtained, most of the colonic goblet cells contained acidic and neutral glycoconjugates with sulphate and vicinal diol groupings, -D-mannose and -D-glucose residues and sialic acid-galactose dimers. These goblet cells were found to undergo changes in histochemical reactivity during upward migration along the crypts; -D-mannose and -D-glucose residues and terminal sialic acidgalactose dimers increased in amount. The striated border of the colonic columnar cells has, likewise, been found to contain such glycoconjugates as were similar in reactivity to those of the goblet cells. The histophysiological significances of glycoconjugates involved in the chicken colonic epithelium have been discussed with special reference to the functional activities of the carbohydrates.  相似文献   
9.
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   
10.
In the colonic epithelium of the chicken, glycoconjugates have been studied by means of selected histochemical methods of light and electron microscopy. According to the results obtained, most of the colonic goblet cells contained acidic and neutral glycoconjugates with sulphate and vicinal diol groupings, alpha-D-mannose and alpha-D-glucose residues and sialic acid-galactose dimers. These goblet cells were found to undergo changes in histochemical reactivity during upward migration along the crypts; alpha-D-mannose and alpha-D-glucose residues and terminal sialic acid-galactose dimers increased in amount. The striated border of the colonic columnar cells has, likewise, been found to contain such glycoconjugates as were similar in reactivity to those of the goblet cells. The histophysiological significances of glycoconjugates involved in the chicken colonic epithelium have been discussed with special reference to the functional activities of the carbohydrates.  相似文献   
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