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1.
Summary The author refers to the results of his investigations carried out with theT. pratense in 1940. He could continue these experiments only in the year 1965. This time he came to the conclusion that three fungi species:T. terrestre Durie &Frey,T. pratense andT. gypseum var.asteroides belong together. He could observe that the cultures of these fungi develop well on some kinds of textile materials. Relying upon these findings he applied the TO-KA-VA method in an inverted way to demonstrate the fungi which had settled on the textiles with the dust of soil. By means of this method he observed thatT. pratense had indeed occurred on some cloths. By further investigation he proved the identity ofT. terrestre Durie &Frey withT. pratense andT. gypseum var.asteroides and demonstrated, that this latter fungus might be the degenerative derivate of the former ones. Finally, he gave as his opinion that the settlement of theT. gypseum var.asteroides is also likely to occur on human clothing; however, far more rarely than that of other kinds of fungi.  相似文献   

2.
Aims: To investigate the influence of different fibre materials on the colonization of textiles by skin bacteria present in human sweat. Methods and Results: The total bacterial content of axillary sweat samples was determined using DNA quantification, and the diversity of bacteria present was investigated. Fabrics made of different fibres were then challenged with these sweat samples; the bacterial DNA was quantified, and the bacterial taxa present were determined. We found differences in the overall colonization, with polyester and polyamide showing the highest bacterial mass. Also, significant differences in the various taxa of bacteria present on the different materials were found. In general, synthetic materials showed a selective growth of bacterial taxa underrepresented in sweat. In contrast, a cellulose‐based material showed only very few taxa, identically with those predominant in sweat. Conclusions: Our investigations demonstrated that besides the bacterial content of sweat itself, the type of material has a strong impact on the bacterial colonization of textiles. Significance and Impact of the Study: Odour generation is one of several effects resulting from an interaction of skin bacteria with textiles, and it is a common experience that there are differences in odour generation by different materials. Our investigations suggest that a selective growth of potentially odour‐producing bacteria may account for this.  相似文献   

3.
Johann, Heinrich, Ferdinand von Autenrieth [1772–1835], was a teacher of anatomy, physiology and pharmacology at the University of Tübingen, Germany. He was the author of a famous textbook on Physiology and one of the earliest pharmacologists [Öffentlicher Lehrer der Arzneykunst]. In his textbooks, he presented a lot of information that and how biological rhythms influenced physiological functions in the human body, the book was used for his medical lectures for students. He can be regarded as on of the earliest chronophysiologists. Most important, he assumed a chemical stimulation responsible for generating the periodicities in the human body.  相似文献   

4.
R. So 《Feddes Repertorium》1972,83(3):129-212
The author enumerates all the critical taxonomical-nomenclatural notes to the results of his „Synopsis systematica-geobotanica Florae Vegetationisque Hungariae”︁, I. — V. (1964–1972), and, according to his view, such referring to the modern floras of central Europe (Hegi ed. 2 1957–1970, Janchen 1956–1960, 1963–1967, Rothmaler 1963, Schmeil-Fitschen edit. Rauh-Senghas 1968, Oberdorfer 1970, Hess-Landolt-Hirzel 1970, Dostál 1950, 1958, etc.). He reports on many species aggregates, critical species, and many new combinations. Often he makes references to the near related southeast and east European taxa. Specially he reports on some species of the genera Aconitum, Aquilegia, Centaurea, Dactylorhiza, Dianthus, Festuca, Galium, Melampyrum, Potentilla, Rhinanthus, Thymus, Valeriana, etc. He also deals with such hybrids occuring in central Europe but are missing in Janchen's and Rothmaler's floras.  相似文献   

5.
Clique sizes for chimpanzee (Pan troglodytes) grooming and for human conversation are compared in order to test Robin Dunbar’s hypothesis that human language is almost three times as efficient a bonding mechanism as primate grooming. Recalculation of the data provided by Dunbar et al. (1995) reveals that the average clique size for human conversation is 2.72 whereas that of chimpanzee grooming is shown to be 2.18. The efficiency of human conversation and actual chimpanzee grooming over Dunbar’s primate grooming model (always one-to-one and a one-way interaction) is 1.27 and 1.25, respectively, when we take role alternation into account. Chimpanzees can obtain about the same efficiency as humans in terms of quantity of social interactions because their grooming is often mutual and polyadic. The fieldwork was supported by a grant from the International Scientific Research Program (07041138 to T. Nishida) of the Monbusho (Japanese Ministry of Education, Science, Sports, and Culture). Michio Nakamura is a research fellow at Japan Monkey Centre. He received his Master of Science degree from Kyoto University in 1996. He is carrying out research on the grooming behavior of chimpanzees at Mahale, Tanzania, for his doctorate.  相似文献   

6.
《Anthrozo?s》2013,26(4):240-254
ABSTRACT

Large herds pose the risk of worsening human—cattle relationships by reducing human contact and thus increasing the risk of accidents. In a survey on 35 dairy farms in Switzerland and Germany, different aspects of human—cow relationships were investigated. The effects of size of herd compared to other factors are presented here. Size of herds in the study varied from eight to 92 cows. On 35 farms the behavior of stockpersons toward their cows was observed directly during milking; personality characteristics of stockpersons were obtained by self-report-inventories, and a questionnaire on management practices was completed. Cows' avoidance distances toward a person were measured, and the social behavior of herds was observed directly.

Size of herd correlated significantly negatively with the percentage of cows with an avoidance distance of zero (rs=-0.52, p≤0.01), but there was no correlation with the median of avoidance distances per herd. Concerning the behavior of stockpersons, size of herd showed a significant negative correlation with the intensity/quality of contact with the cows (rs=-0.51, p≤0.05), and a slightly significant correlation with the total number of talking to/touching interactions with the cows in the milking parlor (rs=-34, p≤0.05). Quality of handling was not affected by size of herd, but the ability of the stockpersons to identify cows (rs=-0.59, p≤0.001), and the frequency of brushing cows decreased with increasing sizes of herd (rs=-0.52, p≤0.01). In regression analysis, the influence of size of herd on the intensity/quality of contact (CON) was confirmed, but showed a much smaller effect than the personality or attitudes of the stockpersons. Additionally, size of herd had no effect on avoidance distances. This was due to the elimination of the effects of CON.

The small influence of size of herd on human-animal relationship parameters was mediated by the intensity of contact with the cows, but is much less important compared to other factors, e.g. the personality and attitudes of stockpersons. Smaller herds facilitated good relationships between a stockperson and his/her cows, but good human—animal relationships were also possible in big herds, and were observed even in the biggest herd (92 cows).  相似文献   

7.
Thomas Hunt Morgan taught at Bryn Mawr College from 1891 until1904. During his years there he concentrated his research interestson embryology; he included regeneration as an integral partof development. This article maintains that Morgan did not abandonhis interest in embryology when he became a geneticist at Columbia,but it deals mainly with his teaching and research while atBryn Mawr. He worked on the development of a great diversityof organisms, plant and animal, he used widely differing experimentalmethods to investigate them, and he concerned himself with manydifferent general and special problems. He strove to investigateproblems that were directly soluble by experimental intervention,and was highly critical, in the best possible way, of the experimentsand interpretations made by his contemporaries, who regardedhim as a leader. He exerted his influence on developmental biologynot only through his research, but also through a number offine textbooks, and by his teaching. During his Bryn Mawr yearshe encouraged his students, undergraduate and graduate, to carryout independent research. He sometimes published with them asco-author, but dozens of articles by his students were publishedwithout carrying Morgan's name as co-author.  相似文献   

8.
Summary Dorsal tubercle and skin of Mertensiella caucasica have been investigated with the electron microscope and enzyme histochemical methods. The epidermis of the tubercle consists of 8–9 cell layers, that of normal dorsal skin of 5–6. The tubercle is filled with large mucous glands which are surrounded by an almost complete layer of smooth muscle cells (myoepithelial cells). Their glandular cells undergo cyclical changes and are characterized by specific secretory granules, which differ from those of the relatively small mucous glands of the normal dorsal skin.In the connective tissue of the tubercle a relatively rich supply of nerve fibres has been found, which in part contain synaptic and dense core vesicles or accumulations of mitochondria. In the normal dorsal skin nerve fibres occur less frequently.The following enzymes have been demonstrated in the mucous glands of the tubercle: SDH, acid phosphatase, unspecific esterases, E 600 resistant esterase.The tubercle seems to stimulate the female cloaca chemically and mechanically.  相似文献   

9.
The presence of calcitonin gene-related peptide (CGRP) in the skin of pig snout and human fingertip was investigated using immunohistochemical techniques. CGRP immunoreactivity was found in Merkel cells and nerve fibres of both species. In pig snout skin, Merkel cells containing CGRP were seen forming clusters at the tips of rete ridge epidermis and in the external root sheath of sinus hair follicles (vibrissae). Human Merkel cells immunostained for CGRP were found isolated or forming small groups in the basal layer of glandular epidermal ridges. In all cases, immunoreactivity was more intense on the side of the Merkel cell facing the associated nerve terminal (which was never positive for CGRP). This part of the Merkel cell has the greatest density of dense-cored granules, suggesting that CGRP must be stored in these granules. Nerve bundles containing CGRP-immunoreactive fibres were found at dermal and hypodermal level, and blood vessels were often surrounded by CGRP nerve fibres. In pig snout skin some nerve fibres containing CGRP penetrated the epidermis and terminated as free endings, and in the human fingertip a small number of CGRP-immunoreactive nerve fibres were seen in Meissner's corpuscles.  相似文献   

10.
Summary The presence of calcitonin gene-related peptide (CGRP) in the skin of pig snout and human fingertip was investigated using immunohistochemical techniques. CGRP immunoreactivity was found in Merkel cells and nerve fibres of both species. In pig snout skin, Merkel cells containing CGRP were seen forming clusters at the tips of rete ridge epidermis and in the external root sheath of sinus hair follicles (vibrissae). Human Merkel cells immunostained for CGRP were found isolated or forming small groups in the basal layer of glandular epidermal ridges. In all cases, immunoreactivity was more intense on the side of the Merkel cell facing the associated nerve terminal (which was never positive for CGRP). This part of the Merkel cell has the greatest density of dense-cored granules, suggesting that CGRP must be stored in these granules. Nerve, bundles containing CGRP-immunoreactive fibres were found at dermal and hypodermal level, and blood vessels were often surrounded by CGRP nerve fibres. In pig snout skin some nerve fibres containing CGRP penetrated the epidermis and terminated as free endings, and in the human fingertip a small number of CGRP-immunoreactive nerve fibres were seen in Meissner's corpuscles.  相似文献   

11.
The aim of this study was to describe the histological structure of the skin of greater rhea (Rhea americana), a ratite bird native to South America. Skin samples were taken from three regions of the trunk (alar, dorsal and pelvic) in 14 specimens which ages ranged from 7 days to adulthood. Serial sections were obtained and subjected to different staining procedures (haematoxylin and eosin, orcein, Masson's trichrome and Gomori), and a morphometric analysis was carried out on stained slides. In general, both epidermis and dermis showed increased thickness of its layers with age. Some differences between regions can be detected both in epidermis and in dermis; for example in adults and 7‐day‐old birds, the stratum corneum of the alar region was thicker than of the dorsal region. In general, the skin of greater rhea was similar to that described in ratites and other birds (a thin epidermis compared to dermis, dermis with scarce elastic fibres, a slender and vascularized stratum superficiale, collagen fibres arranged in three directions). The scarcity of elastic fibres and the general cross‐weaved arrangement of the collagen fibres in the dermis of the adult greater rhea provide strength and flexibility to the dermis, two important features in leather industry.  相似文献   

12.
Summary Immunohistochemistry of peptide-and dopamine--hydroxylase-(DBH)-containing varicose nerve fibres and ganglion cells, respectively, in the guinea pig inferior mesenteric ganglion was investigated followinga) transsection of mesenteric (colonic) branches,b) transsection of central (lumbar splanchnic, intermesenteric and hypogastric) branches, andc) transplantation into the spleen.The findings indicate that pathways of different opioid peptides are not identical Met-enkephalin-and met-enkephalin-arg-phe-(cleavage products from pre-proenkephalin) containing fibres course in central branches to make contact in the inferior mesenteric ganglion. Dynorphin-and -neo-endorphin-(deriving from pre-prodynorphin) containing fibers as well as leu-enkephalin-(included in the dynorphin sequence) fibres appear to rise not only from central and from enteric somata, but also from intraganglionic noradrenergic neurons. Similar pathways seem to be used by VIP-and by neurotensin-immunoreactive cell bodies are rare. Practically all substance P-and most CGRP-immunoreactive fibres enter the ganglion via central branches and, to a large extent, traverse it, but some CGRP-immunoreactive influx appears to come from the intestine. The origin of intraganglionic substance P-and CGRP-immunoreactive fibres after ganglion transplantation remained unidentified. Somatostatin-and neuropeptide Y-immunoreactive fibres predominantly have an intraganglionic origin as have DBH-immunoreactive noradrenergic fibres. The demonstrated alterations in neuropeptide immunoreactivity of intraganglionic and periganglionic nerve fibres following the applied transsection procedures contribute to the present knowledge on origin and destination of peptidergic transmitter segments in the guinea pig inferior mesenteric ganglion. Moreover, the present study provides evidence that intrinsic participitation in intraganglionic fibre supply is more extensive than hitherto believed.Dedicated to Professor Dr. T.H. Schiebler on the occasion of his 65th birthdaySupported by the Deutsche Forschungsgemeinschaft, grant He 919/6-2  相似文献   

13.
Linnaeus's artificial and natural arrangements of plants are examined using a Spearman rank coefficient (which is explained) on his presentations of his own and others' arrangements in the Classes plantarum and elsewhere. There is little alteration in his successive artificial arrangements. In contrast, between 1751 and 1764 his natural arrangements changed considerably, partly in the sequences of genera within orders but mostly by rearrangement of the orders. Comparison with Cesalpino's and Ray's natural arrangements, using the longest-recognized natural groups as signposts, suggests that Linnaeus in his latest natural arrangement (1764) approximated more closely to Ray's. Examination of Linnaeus's successive treatments of certain groups (palms, Zingiberaceae, Hydrocharis-Stratiotes-Vallisneria) and of Giseke's exposition of Linnaeus's lectures on natural groups (1792) shows that Linnaeus was much influenced by habitus and vegetative characters as well as those of the fructification. He recognized orders consisting of a chain of genera linked successively by overall affinity and without any single diagnostic character. Where possible, he preferred characters of the fructification and his ‘secret’ consulting of the habitus is explained as secondary to such characters. It is suggested that in his latest arrangement he approximated more to a scala naturae, as he probably did in zoology about the same time. Within his artificial arrangements Linnaeus kept to sequences of genera as natural as possible. He realized that some groups in his natural arrangements were still artificial, and his aphorism that all genera and species are natural, classes and orders part natural and part artificial, refers to his and others' practice until the natural system could be completed. It is not a statement of the essential natures of these ranks. Linnaeus's distinction in practice between natural and artificial arrangements was less clear-cut than Sachs believed. Linnaeus's rejection of the ancient tree/herb division was empirical, not a reasoned repudiation of an a priori grouping. The tree/herb division could be upheld in his day as obviously natural, not merely accepted on authority.  相似文献   

14.
15.
BackgroundSkin ageing is associated with structure-functional changes in the extracellular matrix, which is in part caused by proteolytic degradation. Since cysteine cathepsins are major matrix protein-degrading proteases, we investigated the age-dependent expression of elastolytic cathepsins K, S, and V in human skin, their in vitro impact on the integrity of the elastic fibre network, their cleavage specificities, and the release of bioactive peptides.MethodsCathepsin-mediated degradation of human skin elastin samples was assessed from young to very old human donors using immunohistochemical and biochemical assays, scanning electron microscopy, and mass spectrometry.ResultsElastin samples derived from patients between 10 and 86 years of age were analysed and showed an age-dependent deterioration of the fibre structure from a dense network of thinner fibrils into a beaded and porous mesh. Reduced levels of cathepsins K, S, and V were observed in aged skin with a predominant epidermal expression. Cathepsin V was the most potent elastase followed by cathepsin K and S. Biomechanical analysis of degraded elastin fibres corroborated the destructive activity of cathepsins. Mass spectrometric determination of the cleavage sites in elastin revealed that all three cathepsins predominantly cleaved in hydrophobic domains. The degradation of elastin was efficiently inhibited by an ectosteric inhibitor. Furthermore, the degradation of elastin fibres resulted in the release of bioactive peptides, which have previously been associated with various pathologies.ConclusionCathepsins are powerful elastin-degrading enzymes and capable of generating a multitude of elastokines. They may represent a viable target for intervention strategies to reduce skin ageing.  相似文献   

16.
There is a lack of relevant methods to assess the colonization of textiles by skin bacteria because present methods are mainly culture-based procedures. Therefore, the goal of this study was to develop a fast and sensitive culture-independent procedure for the quantification of microbial colonization and growth on textiles. We have established a suitable protocol to use DNA quantification as a reliable method for in vitroand in vivoinvestigations of textiles. For DNA extraction, a two-step procedure comprising treatment of the textile with a solution containing Triton X-100 and lysozyme for 1 h and a successive treatment by SDS and proteinase K for 2 h turned out to be most efficient. DNA extracted from textiles and fabrics was than quantified with the highly sensitive PicoGreen fluorescent dye. In vitrochallenge tests demonstrated a strong correlation between numbers of bacteria on textiles and amount of DNA extracted from textiles. Therefore, this method was used to compare different materials after in vivotrials for assessment of their susceptibility for microbial colonization and growth.  相似文献   

17.
Pfaffelhuber in his paper [1] deals with the approximation of the entropy H of finite information sources on the basis of independent observations. He derives an error estimation for the experimental entropy, which depends only on the number of the possible source-cutputs. Using this result he succeeded in giving an upper estimation for the number of independent observations needed for obtaining a reliable approximation of the exact entropy. The aim of this short correspondence is to improve his error estimation and thereby to give a new upper bound for the number of the necessary observations which is nearly the logarithm of E. Pfaffelhuber's one. We mention only that the same assertion holds for the information rate T of observation channels, too.  相似文献   

18.
Theories of religion that are supported with selected examples can be criticized for selection bias. This paper evaluates major evolutionary hypotheses about religion with a random sample of 35 religions drawn from a 16-volume encyclopedia of world religions. The results are supportive of the group-level adaptation hypothesis developed in Darwin’s Cathedral: Evolution, Religion, and the Nature of Society (Wilson 2002). Most religions in the sample have what Durkheim called secular utility. Their otherworldly elements can be largely understood as proximate mechanisms that motivate adaptive behaviors. Jainism, the religion in the sample that initially appeared most challenging to the group-level adaptation hypothesis, is highly supportive upon close examination. The results of the survey are preliminary and should be built upon by a multidisciplinary community as part of a field of evolutionary religious studies. This research was supported by a grant from the Institute for Research on Unlimited Love. David Sloan Wilson is an evolutionary biologist interested in a broad range of issues relevant to human behavior. He has published in psychology, anthropology, and philosophy journals in addition to his mainstream biological research. He is co-author with the philosopher Elliott Sober of Unto Others: The Evolution and Psychology of Unselfish Behavior (Harvard University Press, 1998).  相似文献   

19.
Conclusion Publication of the Vestiges and the rather primitive theory of evolution it expounded thus played a significant role in the careers of Darwin and Wallace. In addition, in spite of his poor opinion of the Vestiges, it presented Huxley with a convenient topic for critical discussion and the opportunity to focus more attention on the subject of evolution. The dynamic interactions among these leading figures of nineteenth-century natural science helped spur the development of more sophisticated models of evolution.Darwin had a proper appreciation of Chambers's contribution to evolutionary thought, although he fully recognized the shortcomings of this work. He understood the importance of allowing fresh ideas about organic change to be ventilated. However, he was primarily concerned with his own theory and viewed all developments in evolutionary biology from this perspective. If he did not give full consideration to Chambers and his book early on, it was due mainly to his feeling that the concepts in the Vestiges were very different from his own; he was therefore reluctant to embrace them as the forerunners of his own theory. As a scholar, he was also troubled by the scientific errors in the book. However, the record demonstrates that he attempted to make amends for any oversight on his part. His generous letter to Chambers's daughter, and his gracious treatment of Chambers during the brief time the latter lived in London, are ample proof of that.The attacks of Huxley, Sedgwick, and other prominent natural historians and geologists at the time, the problems inherent in Chambers's evolutionary theory, and the publication of the Origin, are the major reasons why the Vestiges became a neglected work. Nevertheless, Chambers's contribution will always stand out because, together with those of other late eighteenth- and early nineteenth-century predecessors of Darwin, it laid the foundations of modern evolutionary thought and, more importantly, helped prepare the scientific community for the more fully developed ideas of Darwin and Wallace.  相似文献   

20.

Background  

Q fever, a worldwide zoonotic disease caused by Coxiella burnetii, is endemic in northern Spain where it has been reported as responsible for large series of human pneumonia cases and domestic ruminants' reproductive disorders. To investigate pathogen exposure among domestic ruminants in semi-extensive grazing systems in northern Spain, a serosurvey was carried out in 1,379 sheep (42 flocks), 626 beef cattle (46 herds) and 115 goats (11 herds). Serum antibodies were analysed by ELISA and positive samples were retested by Complement Fixation test (CFT) to detect recent infections.  相似文献   

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