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1.
Anna Bergh Constanza Bernardita Gómez Álvarez Marie Rhodin Pia Gustås 《Acta veterinaria Scandinavica》2018,60(1):81
Background
Swinging limb lameness is defined as a motion disturbance ascribed to a limb in swing phase. Little is known about its biomechanics in dogs, particularly about the body motions that accompany it, such as vertical head and pelvic motion asymmetry. The aim of this study was to describe the changes in vertical head and pelvic motion asymmetry in dogs with induced swinging limb motion disturbance, mimicking a swinging limb lameness. Fore- and hind-limb lameness was induced in ten sound dogs by placing a weight (200 g) proximal to the carpus or tarsus, respectively. Marker-based motion capture by eight infrared light emitting video cameras recorded the dogs when trotting on a treadmill. Body symmetry parameters were calculated, including differences between the two highest positions of the head (HDmax) and pelvis (PDmax) and between the two lowest positions of the head (HDmin) and pelvis (PDmin), with a value of zero indicating perfect symmetry.Results
Induction of swinging forelimb lameness showed significant changes in HDmax (median and range: sound 1.3 mm [??4.7 to 3.1], in the left side ??28.5 mm [??61.2 to ??17.9] and in the right side 20.1 mm [??4.4 to 47.5]) and, induction of swinging hind limb lameness showed significant changes in PDmax (sound 2.7 mm [??7.4 to 7.2], in the left side ??10.9 mm [??22.4 to 0.5] and in the right side 8.6 mm [??3 to 30]), as well as an increased hip movement asymmetry (sound 1.6 mm [??8.6 to 19.9], in the left side ??18.1 mm [??36.7 to 5.4] and in the right side 15 mm [??20.7 to 32.1]) (P?<?0.05).Conclusions
Induced swinging fore- and hind limb lameness resulted in significant increased asymmetry of the maximal vertical displacement movement of the head and pelvis, due to decreased lifting of the head in forelimb lameness and of the pelvis in hind limb lameness. The results suggest that asymmetry of the maximal vertical displacement of the head and pelvis (i.e. lifting) is a key lameness sign to evaluate during examination of swinging limb lameness.2.
The relationship between leaf longevity and growth ring markedness in modern conifer woods and its implications for palaeoclimatic studies 总被引:1,自引:0,他引:1
Growth rings in modern conifer woods were quantitatively analysed to investigate the relationship between leaf longevity and the markedness of the growth ring boundary. Five conifer species exhibiting a wide range of Leaf Retention Times (LRTs) were examined in anatomical sections stored in the Jodrell Laboratory, Royal Botanic Gardens, Kew, Surrey, UK. The species studied were Larix decidua Mill. (deciduous), Pinus sylvestris L. (LRT=1–3 years), Picea abies (L.) H. Karst. (LRT=3–5 years), Cedrus libani A. Rich. (LRT=3–6 years), and Araucaria araucana (Molina) K. Koch (LRT=3–15 years). Two aspects of ring markedness were quantified: (1) the percentage of latewood in each growth ring increment and (2) the difference between the maximum and minimum radial cell diameters in the growth ring increment expressed as a percentage of the maximum cell diameter (percentage diminution). The product of these two parameters was calculated to give a Ring Markedness Index (RMI). Five growth ring increments were measured for each species from poorly provenanced specimens grown in southern England. Statistical analysis of these data shows that there is a significant inverse linear relationship between median LRT and percentage latewood (R2=0.86), percentage diminution (R2=0.77), and RMI (R2=0.91), at P<0.001. These data suggest that leaf longevity exerts an important control on growth ring markedness, in addition to the influence exerted by the growing environment (climatic and edaphic conditions). The significance of these results for the palaeoclimatic analysis of growth rings in fossil woods is discussed with reference to two case-studies: (1) the Early Carboniferous tropical climate of the British Isles and (2) the Early Cretaceous polar climate of the Antarctic Peninsula. 相似文献
3.
A Burkhardt 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》1992,50(3):235-270
Subject of the present report is an investigation of the heredity of 30 iris characteristics. The material basis of this sample of twins (100 monozygotic and 100 dizygotic pairs), the largest ever taken as a basis for the purpose of iris research, consists of standardized colour photographs of the examined persons' irises and iris-microscopic observations. The pairs of twins are compared to 100 non-related casual pairs in order to render a better estimation of the degree of heredity of the features possible. On every occasion several classes were constituted for the concordance verification. These classes result from the number of the classes of the forms of markedness and present different levels of similarity. The different distribution of the twin pairs and the control pairs on the concordance classes are always examined for their statistical significance, and for each group of pairs a concordance value is computed. The intervals between the concordance values of the monozygotic and dizygotic pairs and the control pairs indicate the degree of heredity of the investigated feature. Taking all the compiled factors and conditions into consideration, an evaluation of the features as heredity features is made. Though a hereditary component can be observed for all iris characteristics, only about a third could be called heredity features. Quantity of pigment and the hitherto undescribed limiting layer folds were evaluated as "very good", whereas pigment colour in the fine analysis, quality of the anterior stroma leaf, frequency of iris crypts and iris frill position were judged as "good". Tone of blue, markedness of Woelfflin nodules, quantity and markedness of contractional rings could be evaluated as "moderately good" as to their heredity. On the basis of the prior concordance investigations for each of the 300 pairs, a "similarity index" and a "concordance index" were computed in order to arrive at evidence as to the degree of similarity of the single pairs; i.e. in order to detect the limits of the similarity between non-identical twins and the dissimilarity between identical twins. This concluding investigations lead to the question of the possibility of a diagnosis of genetic identicalness solely on the basis of the comparison of irises. 相似文献
4.
5.
通过对在外加静磁场和正常情况下培养大肠杆菌生长情况的对比分析 ,发现试验条件下所选磁场对大肠杆菌有明显促进生长的作用 ,菌落计数结果表明磁场越强作用效果越明显。对试验结果进行Dunnettt检验发现均具有差异显著性 相似文献
6.
The informative and prognostic value of assessing the brain functional state and memory functions with neurophysiological, electrophysiological, and clinical methods was demonstrated in patients with consequences of ischemic stroke. The character and degree of memory impairments were associated with the localization and extent of the postischemic lesion and correlated with the markedness of pathological signs in the bioelectrical activity of the brain. This allowed identification of predictors of an adverse outcome and yielded valuable information for neurorehabilitation of poststroke patients. 相似文献
7.
Hanyu Chen Bin Ma Peng Gao Hongchi Wang Yongxi Song Linhao Tong Peiwen Li Zhenning Wang 《World journal of surgical oncology》2017,15(1):229
Aim
The aim of this study was to compare the short-term and mid-term effects of laparoscopic intersphincteric resection with the conventional open approach for patients with low rectal cancer through a meta-analysis.Methods
The PubMed, EMBASE, Cochrane, and Ovid databases were searched for eligible studies until March 2017. Operation time, blood loss, circumferential resection margin-positive rate, distal margin length, number of resected lymph nodes, diverting stoma rate, postoperative overall morbidity, anastomotic leakage, and hospital stay were the main short-term effect endpoints. We also examined disease-free survival, overall survival, local recurrence, and post-operational anal function as secondary outcomes to evaluate the mid-term effects of laparoscopic surgery.Results
Five studies involving 620 patients were included in the analyses. Compared with the open approach, the laparoscopic ISR had less blood loss (weighted mean difference [WMD]?=???214.65 ml, 95% CI [??370.44, ??196.13], p?<?0.01), less postoperative overall morbidity (OR?=?0.58, 95% CI [0.40, 0.86], p?<?0.01), and shorter duration of hospital stay (WMD?=???5.87 days, 95% CI [??11.35, ??0.40], p?<?0.05); however, the operation time was significantly longer in the laparoscopic group (WMD?=?47.34 min, 95% CI [4.10, 90.58], p?<?0.05). No other significant differences were observed.Conclusion
Laparoscopic ISR for low rectal cancer offers fewer complications and faster recovery, with similar operation quality and mid-term oncological results than the conventional approach. Although this technique is comparatively more complex than the conventional approach and requires practice, laparoscopic ISR shows great potential as a surgical option and deserves further clinical study.8.
The characteristics of the course of tuberculosis in HIV-infected patients and prophylactic measures
Frolova OP Rakhmanova AG Priĭmak AA Vasil'ev AV Voronin EE Golikov VA Potemina LP Kochetkov NM Tishkevich OA 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1999,(1):67-69
Morbidity in HIV infection and tuberculosis in persons having these two infections in association was analyzed. According to the data for the end of the first quarter of 1997 the presence of association of HIV infection with tuberculosis was found in 91 patients. In 70.3% of cases HIV infection was contacted before the appearance of tuberculosis and in 18.7% of cases, after it; in 11% of cases the order of appearance of these two diseases could not be established. The study revealed that the markedness of the clinical picture of tuberculosis was determined by the progress of HIV infection. 相似文献
9.
Oganov VS 《Journal of gravitational physiology : a journal of the International Society for Gravitational Physiology》2004,11(2):P143-P146
A summary of results of investigations by the author and a brief review of some literature data on human bone tissue deprived of mechanical loading (spaceflight, hypokinesia) is given. The direction and markedness of changes in bone mass--the bone mineral density and the bone mineral content--in different skeletal segments depend on their position relative to the gravity vector. A theoretically expected bone mass reduction was revealed in the trabecular structures of the bones of the lower part of the skeleton (local osteopenia). In the upper part of the skeleton, an increase in the bone mineral content is observed, which is considered as a secondary response and is due to redistribution of body fluids cephalad. The main cause of osteopenia is mechanical unloading. Arguments are presented that osteocyte osteolysis, delayed osteoblast histogenesis, and osteoclast resorption provoked by rearrangement in the hierarchy of the systems of fluid volume and ion regulation, and the endocrine control of calcium homeostasis are the main mechanisms of osteopenia. 相似文献
10.
A Burkhardt 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》1992,50(1-2):83-126
The material basis of this investigation consists of empirical findings and colour photographs of the irises of 200 pairs of twins and 100 control pairs. For the morphological investigation first-born twins and control persons are combined to constitute a comparative group of 400 non-related testees. Research by means of the iris microscope and the evaluation of standardized iris photographs led to the development of a catalogue of features which describes 10 iris characteristics for the iris colour and 20 for the iris structure. For each feature different degrees of markedness are defined and their frequency is determined. Similarly, intraindividual right/left and sex differences as well as age-dependencies and the relation between the features are examined. The setting-up of features includes outlining an iris-colour class system in order to render a better and more practicable determination of eye colour possible. As a substitute for Martin/Schulz's table of eye-colour, which describes only eye-colour phenomena, 4 iris-colour classes are set up whose main criterion of classification is the quantity of pigment. When we consider the testees of all age classes, sex differences have no statistical relevance as for iris colour. Only in the case of male testees may an intensive decrease of blue and brown iris colour in favour of combination colours (yellow pigment colours in particular) be observed during the phase of puberty. Therefore, the brightening postulated in the relevant literature can be confirmed. With regard to female testees, in contrast, pigment shifting is of no statistical relevance. After a slight brightening the irises numerically re-darken at the adult-stage to the initial child level, i.e. they become "dark again" rather than just become "darker". Within the iris structure only the characteristics of the anterior stroma leaf show sex differences. They are, however, only weakly marked and can be described merely as a trend. Over the whole range of the age classes, there are no outstanding structural differences. The different iris characteristics concerning iris colour stand in a significant relation to each other. When we consider the statistically relevant relations between structural features, it becomes clear that particularly reduced and particularly intact iris characteristics correlate. Thus, we can distinguish between an intact type of iris and a reduced one. Three quarters of the testees, however, combine reduced and intact properties with medium degrees of markedness.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
11.
V. S. Oganov 《Human physiology》2003,29(5):539-547
A summary of results of investigations by the author and a brief review of some literature data on human bone tissue deprived of mechanical loading (spaceflight, hypokinesia) is given. The direction and markedness of changes in bone mass—the bone mineral density and the bone mineral content—in different skeletal segments depend on their position relative to the gravity vector. A theoretically expected bone mass reduction was revealed in the trabecular structures of the bones of the lower part of the skeleton (local osteopenia). In the upper part of the skeleton, an increase in the bone mineral content is observed, which is considered as a secondary response and is due to redistribution of body fluids cephalad. The main cause of osteopenia is mechanical unloading. Arguments are presented that osteocyte osteolysis, delayed osteoblast histogenesis, and osteoclast resorption provoked by rearrangement in the hierarchy of the systems of volume regulation, ion regulation, and the endocrine regulation of calcium homeostasis are the main mechanisms of osteopenia. 相似文献
12.
Characterization of the selenite uptake mechanism in the coccolithophore Emiliania huxleyi (Haptophyta) 总被引:1,自引:0,他引:1
The marine coccolithophore Emiliania huxleyi (Haptophyta) requires selenium as an essential element for growth, and the active species absorbed is selenite, not selenate. This study characterized the selenite uptake mechanism using ??Se as a tracer. Kinetic analysis of selenite uptake showed the involvement of both active and passive transport processes. The active transport was suppressed by 0.5 mM vanadate, a membrane-permeable inhibitor of H?-ATPase, at pH 8.3. When the pH was lowered from 8.3 to 5.3, the selenite uptake activity greatly increased, even in the presence of vanadate, suggesting that the H? concentration gradient may be a motive force for selenite transport. [??Se]Selenite uptake at selenite-limiting concentrations was hardly affected by selenate, sulfate and sulfite, even at 100 μM. In contrast, 3 μM orthophosphate increased the K(m) 5-fold. These data showed that HSeO??, a dominant selenite species at acidic pH, is the active species for transport through the plasma membrane and transport is driven by ΔpH energized by H?-ATPase. Kinetic analysis showed that the selenite uptake activity was competitively inhibited by orthophosphate. Furthermore, the active selenite transport mechanism was shown to be induced de novo under Se-deficient conditions and induction was suppressed by the addition of either sufficient selenite or cycloheximide, an inhibitor of de novo protein synthesis. These results indicate that E. huxleyi cells developed an active selenite uptake mechanism to overcome the disadvantages of Se limitation in ecosystems, maintaining selenium metabolism and selenoproteins for high viability. 相似文献
13.
Yu. O. Alyanchikova 《Human physiology》2003,29(1):21-25
The amplitude–temporal parameters of long-latency components of evoked potentials (recorded in symmetrical leads of the parietal regions) were studied during listening to short fragments of classical musical works, which had different emotional expressiveness, presented to healthy subjects by different modes. In random order of presentation, the maximal markedness of the N1-P2 complex and the P3 wave was found to be observed for fragments causing predominantly negative emotional experiences, while the minimal amplitude values and the highest values of the latencies were observed in response to presentation of a musical fragment assessed as emotionally neutral. Significantly higher amplitude values of these oscillations were recorded in the right parietal lead as compared to the left. The data obtained are interpreted in the context of the specific features of perception of short musical fragments in a human with the use of data concerning functional interhemispheric asymmetry when opposite-sign emotional experiences occur. 相似文献
14.
We examine the realization of subject and object agreement in Kadiwéu, where there is only one prefixal position, and neither
subject nor object can consistently be said to win—rather, the person and number of the arguments matters. We argue for an
analysis in terms of the markedness of the 1st person compared to the second, dispreferring 1st person realization. This analysis
is complicated by the fact that 1st person plural does in fact win over 2nd person, but only when it is an object. This turns
out to be a consequence of the fact that the 1st plural object prefix is a portmanteau fusing person and number. The properties
of the exponent inventory, combined with the morphological resources of Kadiwéu (understood here in terms of Trommer’s (2008)
Coherence constraints) and its independent need for inverse marking thus conspire to yield the particular set of argument
realization combinations. We argue that factoring out the analysis into feature-sensitive realization of the feature [+participant]
and [+plural], dispreferred realization of marked [+author], and these morphotactic coherence constraints, provides a better
analysis of crosslinguistic variation and language-internal facts than positing an autonomous language-specific hierarchy
to encode the facts. 相似文献
15.
Andrea Calabrese 《Morphology》2011,21(2):283-325
The inventories of subject clitics in northern Italian varieties are affected by widespread morphological changes. One of
these changes is syncretism. In addition, many dialects display defective paradigms where some of the clitics are missing.
The clitics that undergo syncretism and the clitics that are missing tend to be the same: the first person singular and plural,
the second plural, and, less frequently, the third plural. Working in the framework of Distributed Morphology, I argue that
these clitics are the target of markedness constraints that trigger repair operations leading to either syncretism or the
removal of forms from a paradigm. In particular, I propose two such operations: one is feature deletion, which deletes a marked
feature specification. This operation is always followed by feature insertion, which inserts the opposite value of the deleted
feature specification (this operation leads to syncretism). The other one is obliteration, which deletes a morphosyntactic
node and leads to underspecified morphosyntactic representations (this operation leads to paradigmatic gaps). I investigate
how these operations affect the morphological exponents in PF, creating syncretisms and gaps in exponence. 相似文献
16.
This paper explores two possible connections between the diagnostics for morphological and semantic markedness. One possibility,
a positive correlation, predicts that if a grammatical feature is diagnosed as being morphologically marked then it should
also be semantically marked. This possibility follows from the assumption that features are interpreted as restrictions on
denotations. The second possibility, a negative correlation, predicts that if a grammatical feature is diagnosed as being
morphologically marked then it should be semantically unmarked. This systematic inconsistency follows from the assumption
that features are interpreted as augmenting functions. In our exploration of number marking, we find that the negative correlation
is not only theoretically consistent with the semantic literature (in particular Link, in: Bartsch et al. (eds.) Semantics
and contextual expressions, 1983), but it is also more consistent with the empirical landscape (as noted by Sauerland, in:
Young and Zhou (eds.) Proceedings of Semantics and linguistic theory SALT XIII 2008). As a result, the morphological diagnostics
lend support to the view that plural features are interpreted as augmenting functions. 相似文献
17.
Bernd Wiese 《Morphology》2013,23(2):179-200
The present paper provides a new approach to the form-function relation in Latin declension. First, inflections are discussed from a functional point of view with special consideration to questions of syncretism. A case hierarchy is justified for Latin that conforms to general observations on case systems. The analysis leads to a markedness scale that provides a ranking of case-number-combinations from unmarked to most marked. Systematic syncretism always applies to contiguous sections of the case-number-scale (‘syncretism fields’). Second, inflections are analysed from a formal point of view taking into account partial identities and differences among noun endings. Theme vowels being factored out, endings are classified on the basis of their make-up, e.g., as sigmatic endings; as containing desinential (non-thematic) vowels; as containing long vowels; and so on. The analysis leads to a view of endings as involving more basic elements or ‘markers’. Endings of the various declensions instantiate a small number of types, and these can be put into a ranked order (a formal scale) that applies transparadigmatically. Third, the relationship between the independently substantiated functional and formal hierarchies is examined. In any declension, the form-function-relationship is established by aligning the relevant formal and functional scales (or ‘sequences’). Some types of endings are in one-to-one correspondence with bundles of morphosyntactic properties as they should be according to a classical morphemic approach, but others are not. Nevertheless, endings can be assigned a uniform role if the form-function-relationship is understood to be based on an alignment of formal and functional sequences. A diagrammatical form-function relationship is revealed that could not be captured in classical or refined morphemic approaches. 相似文献
18.
The applicability of artificial neural filter systems as fitness functions for sequence-oriented peptide design was evaluated. Two example applications were selected: classification of dipeptides according to their hydrophobicity and classification of proteolytic cleavage-sites of protein precursor sequences according to their mean hydrophobicities and mean side-chain volumes. The cleavage-sites covered 12 residues. In the dipeptide experiments the objective was to separate a selected set of molecules from all other possible dipeptide sequences. Perceptrons, feedforward networks with one hidden layer, and a hybrid network were applied. The filters were trained by a (1,) evolution strategy. Two types of network units employing either a sigmoidal or a unimodal transfer function were used in the feedforward filters, and their influence on classification was investigated. The two-layer hybrid network employed gaussian activation functions. To analyze classification of the different filter systems, their output was plotted in the two-dimensional sequence space. The diagrams were interpreted as fitness landscapes qualifying the markedness of a characteristic peptide feature which can be used as a guide through sequence space for rational peptide design. It is demonstrated that the applicability of neural filter systems as a heuristic method for sequence optimization depends on both the appropriate network architecture and selection of representative sequence data. The networks with unimodal activation functions and the hybrid networks both led to a number of local optima. However, the hybrid networks produced the best prediction results. In contrast, the filters with sigmoidal activation produced good reclassification results leading to fitness landscapes lacking unreasonable local optima. Similar results were obtained for classification of both dipeptides and cleavage-site sequences. 相似文献
19.
Binnerup SJ Jensen K Revsbech NP Jensen MH Sørensen J 《Applied and environmental microbiology》1992,58(1):303-313
Nitrogen and oxygen transformations were studied in a bioturbated (reworked by animals) estuarine sediment (Norsminde Fjord, Denmark) by using a combination of N isotope (NO(3)), specific inhibitor (C(2)H(2)), and microsensor (N(2)O and O(2)) techniques in a continuous-flow core system. The estuarine water was NO(3) rich (125 to 600 muM), and NO(3) was consistently taken up by the sediment on the four occasions studied. Total NO(3) uptake (3.6 to 34.0 mmol of N m day) corresponded closely to N(2) production (denitrification) during the experimental steady state, which indicated that dissimilatory, as well as assimilatory, NO(3) reduction to NH(4) was insignificant. When C(2)H(2) was applied in the flow system, denitrification measured as N(2)O production was often less (58 to 100%) than the NO(3) uptake because of incomplete inhibition of N(2)O reduction. The NO(3) formed by nitrification and not immediately denitrified but released to the overlying water, uncoupled nitrification, was calculated both from NO(3) dilution and from changes in NO(3) uptake before and after C(2)H(2) addition. These two approaches gave similar results, with rates ranging between 0 and 8.1 mmol of N m day on the four occasions. Attempts to measure total nitrification activity by the difference between NH(4) fluxes before and after C(2)H(2) addition failed because of non-steady-state NH(4) fluxes. The vertical distribution of denitrification and oxygen consumption was studied by use of N(2)O and O(2) microelectrodes. The N(2)O profiles measured during the experimental steady state were often irregularly shaped, and the buildup of N(2)O after C(2)H(2) was added was much too fast to be described by a simple diffusion model. Only bioturbation by a dense population of infauna could explain these observations. This was corroborated by the relationship between diffusive and total fluxes, which showed that only 19 to 36 and 29 to 62% of the total O(2) uptake and denitrification, respectively, were due to diffusion-reaction processes at the regular sediment surface, excluding animal burrows. 相似文献
20.
The present study involved comparison of adhesion of Helicobacter pylori KH202 to immobilized Le(b)-oligosaccharide carried on different carriers, i.e. Leb-oligosaccharide conjugated with polyacrylamide, bovine serum albumin, and dipalmitoylphosphatidylethanolamine (Le(b)-PAA, Le(b)-BSA, and Le(b)-DPPE). All of the Le(b)-oligosaccharide-carrying neoglycoconjugates served as ligands for H. pylori. However, H. pylori required 10-fold and 100-fold quantities of Le(b)-antigen to adhere to Le(b)-PAA and to Le(b)-DPPE in comparison to the quantity of Le(b)-antigen needed to adhere to Le(b)-BSA, respectively. H. pylori adhesion to Le(b)-PAA and Le(b)-DPPE was clearly inhibited by Le(b)-oligosaccharide, but adhesion to Le(b)-BSA was hardly inhibited by the oligosaccharide. Therefore, the carbohydrate carrier affects the affinity of H. pylori KH202 toward Le(b)-antigen, although the bacteria recognize Le(b)-antigen regardless of the carbohydrate carrier. 相似文献