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1.
The measurement of 13 items in the face and nose of 220 young adults (110 males and 110 females) of the Han nationality between the ages of 18 and 21 years has been done in the Henan Province of China. The means and standard deviations have been obtained, and the significant differences in many items between males and females have been proved. Some items influencing outer nasal shape have been analyzed. The correlations between nose height, nose length, and morphologic facial height and physiognomic facial height have been discussed. The ratio and amount of nasal breadth to facial breadth and nasal breadth to interocular breadth have been compared and analyzed, and the differences among the different races and between the sexes have been explained.  相似文献   

2.
Hydrophilic networks based on functionalized hyaluronic acid and on partially acetylated chitosan, respectively, have been obtained. In the case of hyaluronic acid (HA), primary amino functionalities have been introduced along the polysaccharide chains. The ensuing derivatives, i.e., HA-lysine (HA-K), HA-diamino pentane (HA-DAP), and HA-glycine-lysine (HA-GK), have been characterized by high field NMR spectroscopy. NMR 2D-DOSY experiments have allowed us to optimize the purification procedure. Chitosan was made soluble in water by partial acetylation. Cross-linking reactions have been performed using glutaraldehyde. The obtained networks have been qualitatively characterized by means of (13)C CP-MAS NMR technique. The hydrogels have been characterized also in terms of water uptake.  相似文献   

3.
As the result of the study of tetanolysin-producing Clostridium tetani strains, their populations have been found to be markedly heterogeneous with respect to the hemolytic activity of clone cultures. On the basis of normal and dialyzed cultures of selected variants with maximum activity the preparations of tetanolysin have been obtained, and their hemolytic activity and antigenic properties have been studied. Antihemolytic rabbit sera have also been obtained and characterized. Partially purified preparations of tetanolysin with high hemolytic activity have been obtained by the fractionation of C. tetani dialyzed cultures with ammonium sulfate.  相似文献   

4.
Kinetic expressions for the fermentative production of relatively high concentrations [12% (w/v)] of ethanol have been examined. Several expressions which account for both substrate and product inhibition have been formulated, and have been applied to suspended cell and immobilized cell reactors. Experimental data have been used to validate the kinetic expressions used, and the impact of combined inhibition on optimal reactor configuration has been assessed. The process implications of combined substrate and product inhibition for suspended and immobilized cell systems have been discussed.  相似文献   

5.
靛蓝及其同类色素的微生物生产与转化   总被引:2,自引:0,他引:2  
靛蓝类色素广泛应用于印染、食品和医药工业, 其环境友好的合成或生产途径越来越受到人们的关注, 特别是微生物生物合成。已经鉴定和分离了能够合成靛蓝类色素的多种微生物, 并且明确了起催化作用的主要是单加氧酶和双加氧酶。已经克隆和利用了一些加氧酶的基因, 构建了工程菌, 优化了其发酵过程。同时, 微生物合成靛蓝的生物转化也已经起步。这些进展将带来环境友好的靛蓝类色素的合成与生产。  相似文献   

6.
通过对50种水龙骨科(Polypodiaceae)植物的引种栽培,研究了水龙骨科植物的引种方法、栽培管理措施和繁殖技术,初步应用离体保存技术保存了10种水龙骨科植物,并对主要类群做了应用及观赏性状评价。  相似文献   

7.
Receptor glomeruli have been studied in the arterial walls of the pia mater of the human brain and spinal cord by means of the light and electron microscopy methods. Zone of their high concentration have been stated; three types of receptor glomeruli have been determined, as well as 3 types of ultrastructural organization of sensitive terminals.  相似文献   

8.
通过对安徽省6家不同所有制、不同规模、不同经营方式的药品流通企业的实地调研,了解药品流通企业及药品配送工作的基本情况,剖析了药品招标配送中存在的问题,对实施药品集中招标采购配送工作提出政策建议。  相似文献   

9.
Inulinase-expressing microorganisms and applications of inulinases   总被引:2,自引:0,他引:2  
In this review article, inulinase-expressing microorganisms and its potential applications in transformation of inulin into very-high-fructose syrup, bioethanol, and inulooligosaccharides are overviewed. In the past 10 years, many new inulinase producers have been obtained and many genes encoding inulinases from different microorganisms have been cloned and characterized. Some novel processes for exoinulinase overproduction have been developed for bioethanol production and ultra-high-fructose syrup. The endoinulinases have also been used for production of inulooligosaccharides from inulin and inulin-containing materials.  相似文献   

10.
The past eighteen months have provided much progress in the cyclic nucleotide phosphodiesterase (PDE) field. Six new phosphodiesterase genes have been discovered and characterized. In addition, several new highly specific PDE inhibitors have been developed and approved for clinical use. Finally, new strategies have been employed to determine PDE function in model systems including the use of antisense oligonucleotide and disruption techniques.  相似文献   

11.
In order to investigate the special function of tryptophan in peptide hormones, six tryptophan analogues have been synthesized, in which structural resemblance has been grossly retained and potentially essential properties have only partially been varied. The L-enantiomers have been isolated after enzymatic digestion of racemic dipeptide derivatives, and charge-transfer properties of the compounds have been studied.  相似文献   

12.
Two rat neurophysins have been purified by salt precipitation, molecular sieving and ion-exchange chromatography. The proteins, performic-acid oxidized or reduced-alkylated, have been split either by trypsin or by staphylococcal proteinase and fragments have been separated by peptide mapping. Amino acid sequences of tryptic peptides have been determined either directly or after cleaving the large fragments by subtilisin, chymotrypsin, elastase or staphylococcal proteinase and characterizing the subfragments. Tryptic peptides have been ordered through the fragments given by staphylococcal proteinase. The N-terminal sequences of both proteins have also been established by automated degradation.The two usual types of mammalian neurophysins have been identified. One neurophysin belongs to the MSEL-neurophysin family and shows 11 substitutions and a 2-residue C-terminal truncation when compared with bovine MSEL-neurophysin. The other belongs to the VLDV-neurophysin family and shows 8 substitutions when compared with bovine VLDV-neurophysin. There are 23 differences between the MSEL- and VLDV-neurophysins of the rat.  相似文献   

13.
Conditions for the immobilization of specific endonucleases Sal I and Pvu II on BrCN-activated Sepharose 4B have been selected. Some physico-chemical properties of the preparations of immobilized restrictases Sal I and Pvu II have been characterized. The specific and general activity values of the preparations thus obtained have been established. The immobilized enzymes have been used for the multiple restriction of the DNA of phage lambda and the DNA of Neisseria meningitidis.  相似文献   

14.
Polysaccharides containing galactofuranosyl and arabinofuranosyl residues are key components of many microorganisms. Recent investigations have provided a greater understanding of the biosynthetic pathways by which these glycans are assembled. Concomitant with these biochemical studies, an increasing number of chemical syntheses of oligofuranosides have been reported and new methods for their assembly have been developed.  相似文献   

15.
Histoplasmosis occurs sporadically or during outbreaks in endemic areas. The risk for severe forms of histoplasmosis is substantially higher among the growing population of immunocompromised patients. Recent research efforts have focused on analyzing epidemics, identifying risk factors for the disease, developing improved noninvasive diagnostic assays, and assessing the roles of newer antifungal drugs. Guidelines have been published for the prevention of occupationally acquired histoplasmosis and for reducing the risk of disease in patients with HIV infection. A third-generation Histoplasma antigen assay has been developed, which has superior performance characteristics compared to other noninvasive diagnostic tests. Treatment guidelines for the various clinical forms of histoplasmosis have been formulated and updated. Two newer azoles with activity against Histoplasma capsulatum, voriconazole and posaconazole, have been released; in vitro susceptibility data and animal model results have been reported, and treatment experience with these drugs has accumulated.  相似文献   

16.
Based on the data obtained in a series of experiments with laboratory animals, conclusions about changes in the activity of calcium-dependent proteases in the brains of rats with induced neurodegeneration have been drawn. The properties of the proteolytic and regulatory components of the calpain system under the action of neurotoxic agents: amyloid β-peptide and glutamate have been characterized, and the main endogenous regulatory mechanisms of changes in the intensity of calcium-dependent proteolysis have been established. The neuroprotective properties of exogenous calpain regulators acting by different mechanisms: sex steroids and calcium channel regulators have been tested on degeneration models examined.  相似文献   

17.
Debeljuk L  Lasaga M 《Peptides》2006,27(11):3007-3019
Tachykinins are present in the pituitary gland and in brain areas involved in the control of the secretion of pituitary hormones. Tachykinins have been demonstrated to stimulate prolactin release acting directly on the anterior pituitary gland. These peptides have also been revealed to be able to act at the hypothalamic level, interacting with neurotransmitters and neuropeptides that have the potential to affect prolactin secretion. Tachykinins seem to act by stimulating or inhibiting the release of the factors that affect prolactin secretion. Among them, tachykinins have been demonstrated to stimulate oxytocin and vasopressin release, which in turn results in prolactin release. Tachykinins also potentiated the response to vasoactive intestinal peptide (VIP) and reinforced the action of glutamate, which in turn result in prolactin release. They have also been shown to interact with serotonin, a neurotransmitter involved in the control of prolactin secretion. In addition, tachykinins have been shown to inhibit GABA release, a neurotransmitter with prolactin-release inhibiting effect. This inhibition may result in an increased prolactin secretion by removal of the GABA inhibition. On the other hand, tachykinins have also been shown to stimulate dopamine release by the hypothalamus, an action that results in an inhibition of prolactin release. Dopamine is a well known inhibitor of prolactin secretion. In conclusion, although tachykinins have been shown to have a predominantly stimulatory effect on prolactin secretion, especially at the pituitary level, under some circumstances they may also exert an inhibitory influence on prolactin release, by stimulating dopamine release at the hypothalamic level.  相似文献   

18.
Development of arbuscular mycorrhizal (AM) symbiosis with plant root system in term of molecular and cellular events have been analysed. A role of AM symbiosis in plant life has been discussed. Molecular methods for analysis of arbuscular mycorrhizal fungi have been described.  相似文献   

19.
Simberloff  Daniel 《Hydrobiologia》2021,848(9):2399-2420

Although freshwater invasions have not been targeted for maintenance management or eradication as often as terrestrial invasions have, attempts to do so are frequent. Failures as well as successes abound, but several methods have been improved and new approaches are on the horizon. Many freshwater fish and plant invaders have been eliminated, especially by chemical and physical methods for fishes and herbicides for plants. Efforts to maintain invasive freshwater fishes at low levels have sometimes succeeded, although continuing the effort has proven challenging. By contrast, successful maintenance management of invasive freshwater plants is uncommon, although populations of several species have been managed by biological control. Invasive crayfish populations have rarely been controlled for long. Marine invasions have proven far less tractable than those in fresh water, with a few striking eradications of species detected before they had spread widely, and no marine invasions have been substantially managed for long at low levels. The rapid development of technologies based on genetics has engendered excitement about possibly eradicating or controlling terrestrial invaders, and such technologies may also prove useful for certain aquatic invaders. Methods of particular interest, alone or in various combinations, are gene-silencing, RNA-guided gene drives, and the use of transgenes.

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20.
A study has been made of the semi-synthesis of 1,3-diols (anacardic alcohols) from natural phenolic lipid resources from Anacardium occidentale and Anacardium giganteum which have given C15 and C11 derivatives, respectively. An isomeric 1,3-diol (isoanacardic alcohol) has been obtained from cardanol separated from technical cashew nut-shell liquid. Homologous 1,3-diols have been synthesised from a range of synthetic 2-alkyl-, 3-alkyl- and 4-alkylphenols and from 6-alkylsalicylic acids. The natural 1,2-diol, urushiol, from Rhus vernicifera has been purified. All these lipidic compounds have been studied for their complexation and the potential recovery of boron as boric acid.  相似文献   

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