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1.
2.
Induction of rooting in microshoots of Psoraleacorylifolia was achieved within 6–8 days of cultureon half-strength basal Murashige and Skoog's(1962) medium supplemented with 0.005–0.01 mg/lindole-3-acetic acid (IAA) and 2% (w/v) sucrose. Rooting was drastically reduced and friable callusformed at the cut end of the microshoots when themedium was supplemented with a higher concentration ofauxin. Rooting was totally inhibited when themicroshoots were cultured in vitro undercontinuous light. However, the maximum percentage ofmicroshoots rooted when incubated in continuous lightfor 4 weeks before transfer to the rooting media.Peroxidase activity increased considerably duringroot induction indicating a key role of peroxidase inrooting of microshoots of Psoralea corylifolia invitro.  相似文献   

3.
ABSTRACT.
  • 1 The elemental composition of 249 adult Brimstone butterflies (Gonepteryx rhamni L.) was studied by wavelength dispersive X-ray fluorescence spectrometry, to determine whether site/population-specific differences could be detected. The chemical elements studied were K, Ca, Fe, Cu, Zn, Ti, P, CI and S.
  • 2 Marked differences were found in the chemical composition of the two sexes, and between individuals caught on different sites and in different years and seasons.
  • 3 Multivariate analyses of the data using principal component analysis and canonical variate analysis showed a clear separation of the butterflies by sex, and within each sex, by seasons. Of the elements studied, the main discriminating ones for this butterfly were K, Ca, P, Zn, CI and S.
  • 4 Whilst differences in chemical composition appear to result from variations in the composition of soil and food-plants in different localities, any site/population-specific differences are soon masked by the passage of time, as adults age and feed. This makes the technique of limited value in the study of dispersal in this species.
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4.
S H Bryant  C E Lawrence 《Proteins》1991,9(2):108-119
A statistical analysis of ion pairs in protein crystal structures shows that their abundance with respect to uncharged controls is accurately predicted by a Boltzmann-like function of electrostatic potential. It appears that the mechanisms of protein folding and/or evolution combine to produce a "thermal" distribution of local nonbonded interactions, as has been suggested by statistical-mechanical theories. Using this relationship, we develop a maximum likelihood methodology for estimation of apparent energetic parameters from the data base of known structures, and we derive electrostatic potential functions that lead to optimal agreement of observed and predicted ion-pair frequencies. These are similar to potentials of mean force derived from electrostatic theory, but departure from Coulombic behavior is less than has been suggested.  相似文献   

5.
The current study was conducted to provide normative data on actigraphic dichotomy index (I?<?O) (the percentage of in bed activity counts that are less than the median of out of bed counts) in healthy population and to assess whether the I?<?O could be an effective index in discriminating the circadian motor activity of cancer patients from healthy controls. In this retrospective study, we recovered 408 actigraphic records from two databases: healthy controls (n?=?182; 79 males; mean age 38.7?±?12.6) and patients with metastatic colorectal cancer (n?=?226; 149 males; mean age 58.4?±?11.4). Beside the usual actigraphic sleep parameters (time in bed, sleep onset latency, total sleep time, wake after sleep onset, sleep efficiency, number of awakenings, and mean motor activity), we also computed the dichotomy index and number of actigraphic wake parameters, namely, diurnal motor activity, diurnal total sleep time, number of sleep episodes, and the mean duration of the longest diurnal sleep episode. Using the Youden index, we calculated the cut off value that performed the best for I?<?O and actigraphic wake parameters. Finally, we created Receiver Operator Characteristic curves to test the efficacy of each actigraphic parameter to discriminate cancer patient from healthy controls. Mean I?<?O was 99.5% (SD, 0.48%) in the healthy group, as compared to 96.6% (SD, 3.6%) in the cancer group (p?<?0.0001). Important age-related effects appeared unlikely after performing both the main analysis with age as a covariate, and a subset analysis in 104 subjects matched for age and sex. In the main analysis, all actigraphic parameters, except total sleep time, significantly differentiated the two groups of participants. However, the I?<?O was the one that clearly performed best. Here, we provide the first large dataset on I?<?O in healthy subjects, we confirm the relevance of this circadian index for discriminating advanced stage colorectal cancer patients from healthy subjects, and we lay the grounds for further investigations of this circadian index in patients with other chronic diseases.  相似文献   

6.
Novel 3-substituted-1-aryl-5-phenyl-6-anilino-pyrazolo[3,4-d]pyrimidin-4-ones of pharmacological significance were synthesized by the reaction of ethyl-(5-amino-3-methylthio-1-aryl-5-phenyl-2H-pyrazole)-4-carboxylates 3ac with S-methyl diphenyl thiourea independently to produce 1-aryl-3-thiomethyl-5-phenyl-pyrazolo[3,4-d]pyrimidines 4ac in DMF with catalytic amount of K2CO3, which on further treatment with different aromatic amines independently under same reaction conditions generated for compounds 5al. The compounds were screened for the anti-inflammatory activity and evaluated for ulcerogenic potential. The compounds 5i exhibited superior anti-inflammatory activity in comparison with diclofenac sodium and comparable activity with celecoxib at a dose of 25 mg/kg. The other compounds 4c, 5c, 5f and 5l were found as active with inhibition of edema in the range of 35–39 after 3 h of administration of test compounds. The ulcerogenic potential of active compounds was observed to be quite lesser as compared to standard. COX-2 docking score of the active compound 5i was found to be better than standard celecoxib.  相似文献   

7.
Purpose: Extracellular matrix (ECM) deposition and remodelling in skin and lungs of systemic sclerosis (SSc) subjects lead to release of metabolites/biomarkers into circulation. We investigated if biomarkers of ECM degradation (biglycan and elastin) and macrophage activation (citrullinated vimentin) could identify diffuse SSc (dSSc) subjects from controls and the biomarkers discriminative power.

Methods: DSSc subjects (n?=?40) fulfilling the 2013 EULAR/ACR classification criteria were divided in early (<2years of symptoms) and late (≥10 years of symptoms). Early were subdivided into intermediate and rapid skin thickness progression rate (STPR). Twenty controls were included. Citrullinated and matrix metalloproteinase (MMP)-2/8-degraded vimentin (VICM), MMP-9/12-degraded biglycan (BGM) and MMP-7-degraded elastin (ELM-7) were assessed in serum. Analysis between groups was by Kruskal–Wallis and ROC AUC for discriminative power.

Results: VICM and BGM levels were increased in early compared with late dSSc (p<?=0.023). VICM was increased in rapid and intermediate STPR compared with controls (p<?=0.025). No differences in ELM-7 levels were observed. AUC of VICM was 0.71 for early versus late dSSc and BGM had an AUC of 0.79 for dSSc versus controls.

Conclusion: This pilot study found differences in biomarker levels between early and late dSSc. This study offers new perspectives of ECM metabolites as potential biomarkers of dSSc.  相似文献   


8.
Homalodisca vitripennis (Germar) (=H. coagulata [Say]) (Hemiptera: Cicadellidae) invaded French Polynesia in 1999. A classical biological control program against H. vitripennis was initiated in 2004 aiming to introduce the exotic egg parasitoid Gonatocerus ashmeadi (Girault) (Hymenoptera: Mymaridae) to the Society Islands archipelago. Prior to any release, two risks were assessed: (a) continued uncontrolled H. vitripennis spread and proliferation in French Polynesia, and (b) non-target impacts by G. ashmeadi on indigenous French Polynesian cicadellids. The primary risk of H. vitripennis is its potential to vector the lethal plant bacterium, Xylella fastidiosa. While the presence of X. fastidiosa in French Polynesia has not yet been demonstrated, the presence of uncontrolled H. vitripennis greatly elevates the risk of a disease outbreak and thus represents a major threat for numerous plant species. Assessing the risk of G. ashmeadi introduction for native cicadellids first required an inventory of the Cicadellidae of the Society Islands, resulting in at least 14 cicadellid species (nine not previously recorded). The risk to these species of attack by G. ashmeadi was assessed using four criteria: (1) their phylogenetic relationships to known hosts of G. ashmeadi, and their similarity in (2) body size, (3) egg laying biology, and (4) ecology. All indigenous cicadellid species found were considered to be at low risk of attack because they differed greatly from all known hosts for G. ashmeadi: (1) none of the indigenous species are in the tribe Proconiini, (2) all were very small and, when possible to determine, (3) lay tiny single eggs, which (4) are deposited on the undersides of leaves of trees. These results persuaded the French Polynesian Government that the benefits of establishing G. ashmeadi for H. vitripennis control outweighed the serious potential risks associated with either delaying release or not releasing G. ashmeadi in French Polynesia. Releases of G. ashmeadi in Tahiti began in May 2005.  相似文献   

9.
10.
Summary. An alteration of low density lipoprotein (LDL) apolipoprotein (apo) B-100 structure by direct oxidative modification is an important mechanism involved in atherogenesis. There is difficulty in quantifying this type of modification because a lack of specific assays. The use of N(O,S)-ethoxycarbonyl trifluoroethyl amino acid esters for a rapid and sensitive determination of 6-hydroxy-2-aminocaproic acid (HACA), a highly specific marker of metal catalyzed protein oxidation, by using standard gas chromatography/electron impact mass spectrometry, is discussed. The derivatives are formed by the unlabored reaction of amino acids with ethylchloroformate plus trifluoroethanol plus pyridine. Femtomole levels of HACA can be reproducible measured in different LDL preparations subjected to oxidative damage in the presence of iron or copper. HACA determination compares well with the measurement of carbonyl groups that are generally accepted as a nonspecific index of protein oxidation. Thus, the method could prove to be a sensitive assay for studying specific apoB-100 modification.  相似文献   

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