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141.
The determination and promotion of the system of shoe sizing requires accurate knowledge of morphological properties of the foot and lower leg of the tested population. Similarly it is necessary to establish the occurrence and regional distribution of definite sizes in the tested population. Possible regional differences in morphological properties must not be ignored because it has been established by means of anthropological measuring that both foot dimensions and foot shapes differ between populations and within the same population. This has been proven by the investigation of body measures, carried out for the purpose of establishing a system of footwear sizes, which was executed on a randomly selected sample of 4,268 healthy and normally developed males aged 18-22. The investigation was carried out in 1993 on five locations each of which representing a definite region of the Republic of Croatia: Jastrebarsko (central), Koprivnica (northwestern), Pula (southwestern), Sinj (southern) and Pozega (northeastern). The measuring instrument was 31 foot and lower-leg sizes according to the existing ISO standards for footwear. Interregional differences are significant in all body measures. The role and the contribution of individual measures to these differences has been established by means of discriminatory analysis with regions as a priori defined samples. In order to constitute a convenient and purposeful standard for the footwear size system it is necessary to work out a database with referent values for the same system. 相似文献
142.
Cano JM Laurila A Pało J Merilä J 《Evolution; international journal of organic evolution》2004,58(9):2013-2020
The additive genetic variance-covariance matrix (G) is a concept central to discussions about evolutionary change over time in a suite of traits. However, at the moment we do not know how fast G itself changes as a consequence of selection or how sensitive it is to environmental influences. We investigated possible evolutionary divergence and environmental influences on G using data from a factorial common-garden experiment where common frog (Rana temporaria) tadpoles from two divergent populations were exposed to three different environmental treatments. G-matrices were estimated using an animal model approach applied to data from a NCII breeding design. Matrix comparisons using both Flury and multivariate analysis of variance methods revealed significant differences in G matrices both between populations and between treatments within populations, the former being generally larger than the latter. Comparison of levels of population differentiation in trait means using Q(ST) indices with that observed in microsatellite markers (F(ST)) revealed that the former values generally exceeded the neutral expectation set by F(ST). Hence, the results suggest that intraspecific divergence in G matrix structure has occurred mainly due to natural selection. 相似文献
143.
Sabo TJ Kaluderović GN Poleti D Karanović L Boccarelli A Cannito F Natile G 《Journal of inorganic biochemistry》2004,98(8):1378-1384
The cytotoxicities of two platinum(IV) complexes of formula [PtX2(eddp)].nH2O (eddp=ethylenediamine-N,N'-di-3-propionate, X=chloro [I] or bromo [II], n=1 or 1.24) are reported. The complexes have been obtained by direct reaction of potassium hexahaloplatinate(IV) with H2eddp.2HCl followed by addition of a base (LiOH). The crystal and molecular structure has confirmed that the complex with bromo ligands, similarly to the complex with chloro ligands previously reported, has trans configuration of the halogens. In both the chloro and bromo complexes there appear to be intramolecular N-H...X interactions which account for a narrowing of the corresponding X-Pt-N angles below 90degrees. The trans isomer (configuration index OC-6-13, two nitrogens and two oxygens of eddp bound in the equatorial plane) is the only one obtained in the reaction of hexahaloplatinate(IV) with the eddp ligand while a similar reaction performed with ethylenediamine-N,N'-diacetate (edda) affords exclusively the symmetrical cis-isomer (configuration index OC-6-33, equatorial nitrogen and axial oxygen atoms of edda). The longer chain of the propionato groups (as compared to the acetato ones) is responsible for such a change in preferred configuration. NMR data have revealed a very large diastereotopic splitting of the propionato methylene protons to the nitrogens (0.88 ppm). The trans disposition of the halogen ligands in the compounds with eddp leads to deactivation of platinum(IV) complexes in comparison to those with edda having cis disposition of the leaving chlorides (human ovarian cancer cell line A2780, IC50 [muM] of 92.6 +/- 12 and 30.3 +/- 7.5 for [I] and [II], respectively). 相似文献
144.
Paździor G Langner M Chmura A Bogusławska D Heger E Chorzalska A Sikorski AF 《Cellular & molecular biology letters》2003,8(3):639-648
Spherocytosis is a hereditary disease. It results from mutations in genes that encode proteins participating in the attachment of the membrane skeleton to the plasma membrane bilayer of the erythrocyte. In affected cells, interaction between the spectrin-actin meshwork and integral membrane proteins is altered. This results in the weakening of plasma membrane mechanical resistance and diminishing its elasticity. Since defective cells are prone to mechanical destruction and phagocytosis in the spleen, the fraction of morphologically-altered erythrocytes is rather small; this in turn means such an examination is prone to errors. In this paper, we describe a simple method which could be useful in the identification of red blood cells with altered osmotic properties. The method is based on the measurement of the amount of light scattered by a suspension of the red blood cells, during which cells are exposed to osmotic stress in the stopped-flow regime. The obtained plots are fitted to a mathematical formula, the parameters of which can be used as quantitative indicators of the changes in red blood cells' osmotic features. Two types of spherocytotic samples were examined: those with a proven deficiency in ankyrin and those with a decrease in the band 3 anion transporting protein. The presented data show that this method gives a reliable indication of altered osmotic properties of the spherocytic cells. 相似文献
145.
M Paál G Bajtai M Ambrus G Horváth M Kovács K Barna 《Acta morphologica Academiae Scientiarum Hungaricae》1977,25(4):285-288
HBsAg was detected by indirect immunofluorescent method in liver biopsy specimens of 60 symptom-free HBsAg positive volunteers. An effort was made to separate from the material intact cells suitable for studying HBsAg localization in the liver cells. 相似文献
146.
Thalita Ewellyn Batista Sales Marques Leila Rodrigues de Mendon?a Marília Gabriela Pereira Tiago Gomes de Andrade Norberto Garcia-Cairasco Maria Luisa Pa?ó-Larson Daniel Leite Góes Gitaí 《PloS one》2013,8(8)
It is well recognized that the reference gene in a RT-qPCR should be properly validated to ensure that gene expression is unaffected by the experimental condition. We investigated eight potential reference genes in two different pilocarpine PILO-models of mesial temporal lobe epilepsy (MTLE) performing a stability expression analysis using geNorm, NormFinder and BestKepeer softwares. Then, as a validation strategy, we conducted a relative expression analysis of the Gfap gene. Our results indicate that in the systemic PILO-model Actb, Gapdh, Rplp1, Tubb2a and Polr1a mRNAs were highly stable in hippocampus of rats from all experimental and control groups, whereas Gusb revealed to be the most variable one. In fact, we observed that using Gusb for normalization, the relative mRNA levels of the Gfap gene differed from those obtained with stable genes. On the contrary, in the intrahippocampal PILO-model, all softwares included Gusb as a stable gene, whereas B2m was indicated as the worst candidate gene. The results obtained for the other reference genes were comparable to those observed for the systemic Pilo-model. The validation of these data by the analysis of the relative expression of Gfap showed that the upregulation of the Gfap gene in the hippocampus of rats sacrificed 24 hours after status epilepticus (SE) was undetected only when B2m was used as the normalizer. These findings emphasize that a gene that is stable in one pathology model may not be stable in a different experimental condition related to the same pathology and therefore, the choice of reference genes depends on study design. 相似文献
147.
Geosmithia spp. (Ascomycota: Hypocreales) are little-studied, dry-spored fungi that occur in galleries built by many phloeophagous bark
beetles. This study mapped the distribution and environmental preferences of Geosmithia species occurring in galleries of temperate European bark beetles. One hundred seven host tree samples of 16 tree species
infested with 23 subcortical insect species were collected from across Europe during the years 1997–2005. Over 600 Geosmithia isolates from the beetles were sorted into 17 operational taxonomic units (OTUs) based on their phenotype similarity and
phylogeny of internal transcribed spacer (ITS) region of rDNA (ITS1-5.8S-ITS2). The OTUs represent six known species and eight
undescribed taxa. Ninety-two samples infested with subcortical insects were characterized by the presence/absence of OTUs
and the similarity among the samples was evaluated. Geographically distant populations of the same beetle species host relatively
uniform Geosmithia communities across large geographic areas (ranging from southern Bulgaria to the Czech Republic). This suggests effective
dispersal of Geosmithia spp. by bark beetles. Clustering of similar samples in ordination analysis is correlated predominantly with the isolation
source (bark beetles and their respective feeding plant), but not with their geographical origin. The composition of the Geosmithia OTU community of each bark beetle species depends on the degree of isolation of the species’ niches. Thus, Geosmithia communities associated with regularly co-occurring bark beetle species are highly similar. The similarity decreases with
decreasing frequency of beetle species’ co-occurrence, a pattern resembling that of entomochoric ophiostomatoid fungi. These
findings suggest that: 1) communities of Geosmithia spp. are vector-specific; 2) at least in some cases, the association between Geosmithia OTUs and bark beetles may have been very stable and symbioses are likely to be a fundamental factor in the speciation of
Geosmithia fungi; and 3) that even nonsticky spores of Geosmithia are suitable for maintaining an insect–fungus association, contrary to previous hypotheses.
An erratum to this article can be found at 相似文献
148.
Marek Kowalczyk Piotr Siermontowski Dariusz Mucha Tadeusz Ambro?y Marcin Or?owski Krzysztof Zinkiewicz Waldemar Kurpiewski Krzysztof Pa?nik Iwona Kowalczyk Agnieszka Pedrycz 《PloS one》2016,11(2)
Colorectal cancer (CRC) is the second most common cause of death worldwide. According to the theory by Vogelstein, colorectal carcinogenesis involves a series of successive changes in the normal colonic mucosa, starting with excessive proliferation and focal disorders of intestinal crypts, followed by adenoma and its subsequent malignant transformation. The first identifiable changes in CRC carcinogenesis are aberrant crypt foci (ACF). ACF are invisible during routine colonoscopy yet are well identifiable in chromoendoscopy using methylene blue or indigo carmine. High-resolution colonoscopes are used for assessment of ACF. The aim of the present study was to evaluate the usefulness of standard-resolution colonoscopy for identification of rectal ACF. The following parameters were evaluated: duration of chromoendoscopy of a given rectal segment, type of ACF, sensitivity and specificity of endoscopy combined with histopathological evaluation. The mean duration of colonoscopy and chromoendoscopy was 26.8 min. In the study population, typical ACF were found in 73 patients (p = 0.489), hyperplastic ACF in 49 (p = 0.328), and dysplastic ACF in 16 patients (p = 0.107). Mixed ACF were observed in 11 individuals (p = 0.073). The sensitivity of the method was found to be 0.96 whereas its specificity 0.99.Identification of rectal ACF using standard-resolution colonoscopy combined with rectal mucosa staining with 0.25% methylene blue is characterised by high sensitivity and specificity. 相似文献
149.
Successful cryopreservation of Q. robur germplasm as plumules (i.e. shoot apical meristems of embryos) is described in this paper. After excision from the recalcitrant
seeds and preliminary storage in 0.5 M sucrose solution (18 h), the plumules were subjected to cryoprotection (in 0.75 M sucrose,
followed by 1.0 M sucrose and 1.5 M glycerol solutions), and next to desiccation (over silica gel or in nitrogen gas) and
cooling (in slush at –210°C or in vials filled with liquid nitrogen, LN, −196°C), and were then cryostored for 24 h. High
percentage of survival was obtained after cryostorage (21–67%, depending on pretreatment, assessed in vitro by greening plumules
that increased in size). Desiccation of plumules over silica gel resulted in significantly higher survival after cryopreservation
(58%) in comparison with desiccation in nitrogen gas (29%), with regrowth (shoots with leaves) 5–18%. The extent of plumule
desiccation was comparable in both methods, in which drying of plumules for 20 min decreased the water content to 0.5–0.6
g H2O g−1 dry weight before LN exposure. The type of LN exposure did not significantly influence plumule survival and regrowth after
cryostorage. Plumules isolated from acorns of four provenances survived cryostorage after cryoprotection followed by desiccation
over silica gel and direct cooling in vials with LN (survival 51–76%, regrowth 8–20%). Normal plants developed from the recovered
shoots after rooting. The presented protocol for Q. robur plumule cryopreservation may offer a potential approach for establishing germplasm conservation in gene banks for Quercus species. 相似文献