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121.
Extracts of Salvia species are used in traditional medicine to treat various diseases. The economic importance of this genus has increased in recent years due to evidence that some of its secondary metabolites have valuable pharmaceutical and nutraceutical properties.The bioactivity of sage extracts is mainly due to their content of terpenes and polyphenols. The increasing demand for sage products combined with environmental, ecological and climatic limitations on the production of sage metabolites from field-grown plants have led to extensive investigations into biotechnological approaches for the production of Salvia phytochemicals. The purpose of this review is to evaluate recent progress in investigations of sage in vitro systems as tools for producing important terpenoids and polyphenols and in development of methods for manipulating regulatory processes to enhance secondary metabolite production in such systems.  相似文献   
122.
Proyseria decora (Dujardin, 1845) (the type-species of the genus Proyseria Petter, 1959) is redescribed on the basis of specimens from Alcedo atthis (L.) (Coraciiformes: Alcedinidae) from Iran. P. petterae n. sp. is described from Corythornis vintsioides (Eydoux & Gervais) (Alcedinidae) from Madagascar by light and scanning electron microscopy. Proyseria sp. from Alcedo euryzona Temminck from continental Malaysia is described on the basis of a single male specimen. Stegophorus alcedonis Puqin, Yanyin & Guocal, 1991 from A. atthis in China is transferred to the genus Proyseria as P. alcedonis n. comb. The generic diagnosis of Proyseria is amended. Review of the species of the genera Proyseria and Stegophorus Wehr, 1934 is presented.  相似文献   
123.
Phenylethanoid glycosides are naturally occurring water-soluble compounds with remarkable biological properties that are widely distributed in the plant kingdom. Verbascoside is a phenylethanoid glycoside that was first isolated from mullein but is also found in several other plant species. It has also been produced by in vitro plant culture systems, including genetically transformed roots (so-called ‘hairy roots’). Verbascoside is hydrophilic in nature and possesses pharmacologically beneficial activities for human health, including antioxidant, anti-inflammatory and antineoplastic properties in addition to numerous wound-healing and neuroprotective properties. Recent advances with regard to the distribution, (bio)synthesis and bioproduction of verbascoside are summarised in this review. We also discuss its prominent pharmacological properties and outline future perspectives for its potential application.  相似文献   
124.
125.
The genus Verbascum (mulleins), belonging to the family Scrophulariaceae, comprises about 360 species of flowering plants. The leaves, flowers and whole aerial parts of Verbascum spp. have been widely used in traditional medicine for the treatment of respiratory and inflammatory disorders and also display powerful wound healing activity. Verbascum species are found to accumulate several groups of bioactive molecules, therefore they might be utilized as attractive sources of new (drug) leads. The present review attempts to provide an up-to-date comprehensive overview on phytochemical and pharmacological aspects of Verbacum spp. research along with some successful examples of growing (and transforming) mulleins in vitro.  相似文献   
126.

Background

Phenylalanine and tyrosine are precursor amino acids required for the synthesis of dopamine, the main neurotransmitter implicated in the neurobiology of schizophrenia. Inflammation, increasingly implicated in schizophrenia, can impair the function of the enzyme Phenylalanine hydroxylase (PAH; which catalyzes the conversion of phenylalanine to tyrosine) and thus lead to elevated phenylalanine levels and reduced tyrosine levels. This study aimed to compare phenylalanine, tyrosine, and their ratio (a proxy for PAH function) in a relatively large sample of schizophrenia patients and healthy controls.

Methods

We measured non-fasting plasma phenylalanine and tyrosine in 950 schizophrenia patients and 1000 healthy controls. We carried out multivariate analyses to compare log transformed phenylalanine, tyrosine, and phenylalanine:tyrosine ratio between patients and controls.

Results

Compared to controls, schizophrenia patients had higher phenylalanine (p<0.0001) and phenylalanine: tyrosine ratio (p<0.0001) but tyrosine did not differ between the two groups (p = 0.596).

Conclusions

Elevated phenylalanine and phenylalanine:tyrosine ratio in the blood of schizophrenia patients have to be replicated in longitudinal studies. The results may relate to an abnormal PAH function in schizophrenia that could become a target for novel preventative and interventional approaches.  相似文献   
127.
A new method for on-spot detection and characterization of organic compounds resolved on thin layer chromatography (TLC) plates has been proposed. This method combines TLC with dielectric barrier discharge ionization (DBDI), which produces stable low-temperature plasma. At first, the compounds were separated on TLC plates and then their mass spectra were directly obtained with no additional sample preparation. To obtain good quality spectra the center of a particular TLC spot was heated from the bottom to increase volatility of the compound. MS/MS analyses were also performed to additionally characterize all analytes. The detection limit of proposed method was estimated to be 100 ng/spot of compound.  相似文献   
128.
MDg3 is a family of mobile dispersed genetic elements represented by 15 copies in the haploid genome of D. melanogaster and flanked, like other similar elements, by the regions of homology. In the present work, these regions of mdg3 have been sequenced. The existence of perfect direct repeats 268 base pairs long has been demonstrated. Inverted repeats are located on the gene distal side of them. It is possible to construct a perfect 8 b.p. palindrome or a slightly mismatched 18 b.p. palindrome. The inverted repeats are flanked by two short 5 b.p. direct repeats.  相似文献   
129.
The whole-length mobile dispersed genetic element mdg1 has been cloned from D. melanogaster genome. It contains DNA fragments described earlier as Dm225 and Dm234, Mdg1 is 7.2 kb long and framed with two direct repeats of 300-400 base pairs each. Mdg1 family is represented by about 25 copies in the genome of flies and by 200 copies in the genome of cultured cell line 67J25D. Virtually all the copies in the genome of D. melanogaster have the same restriction map. Oligo(dA)-oligo(dT) regions were found within mdg1.  相似文献   
130.
Expression in milk of transgenic farm animals is one of the most effective ways to produce eukaryotic recombinant proteins. In this review, we discuss the problems of the appropriateness of selecting this expression system for the production of proteins and the development characteristics of appropriate production processes.  相似文献   
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