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1.
The ‘rediscovery’ of Mendel’s laws in 1900 was a turning point in modern research of heredity/genetics. According to the traditional view, adopted and fostered by many textbooks of genetics, Mendel’s principles were presented in the first half of 1900 simultaneously and independently by three biologists (H. de Vries, C. Correns, E. v. Tschermak-Seysenegg). Having thus laid the foundations of further development, the ‘rediscovery’ continues to attract considerable interest. Since the 1950s, however, serious questions arose concerning both the chronology and specific conceptual achievement of the scientists involved. Not only the independence but also parallelism was analysed in the context of individual research programmes of these three scholars. The youngest of them, Erich v. Tschermak-Seysenegg, was even excluded from the list of ‘rediscoverers’. The aim of this paper is to use new archival evidence and approximate the contribution of the physiologist and ophthalmologist Armin von Tschermak-Seysenegg (1870–1952) to the events of 1900 and 1901.  相似文献   

2.
Edward O. Wilson's forays into human sociobiology have been the target of persistent, vehement attack by his Harvard colleague in evolutionary biology, Richard C. Lewontin. Through examination of existing documents in the case, together with in-depth personal interviews of Wilson, Lewontin, and other biologists, the reasons for Wilson's stance and Lewontin's criticisms are uncovered. It is argued that the dispute is not primarily personally or politically motivated, but involves a conflict between long-term scientific-cum-moral agendas, with the reductionist program as a key issue. It is concluded that it is in the interest of both disputants to keep the controversy alive.  相似文献   

3.
Genetic background plays an important role in the development of Dupuytren’s disease. A genome-wide association study (GWAS) showed that nine loci are associated with the disease, six of which contain genes that are involved in Wnt signaling (WNT2, WNT4, WNT7B, RSPO2, SFRP4, SULF1). To obtain insight in the role of these genes, we performed expression studies on affected and unaffected patient’s tissues. Surgically obtained nodules and cords from eight Dupuytren’s patients were compared to patient-matched control tissue (unaffected transverse palmar fascia). The Wnt-related genes found in the GWAS, the classical Wnt-downstream protein β-catenin, as well as (myo)fibroblast markers were analyzed using real-time qPCR and immunohistochemical stainings for mRNA levels and protein levels, respectively. The collagen-coding genes COL1A1 and COL3A1 were highly upregulated on mRNA level, both in cords and nodules. Three Wnt-related genes were found to be differently regulated compared to control tissue: WNT2 was downregulated in nodules, WNT7B was upregulated in nodules, and SFRP4 was upregulated in nodules and cords. Immunohistochemistry revealed significantly less staining of Wnt2 in cords, but significantly more staining for Wnt7b in nodules. There was significantly more staining of α-SMA in nodules and cord and β-catenin in nodules than in control tissue. We found differences in expression, both at mRNA and protein level, in several Wnt-related genes found earlier to be associated with Dupuytren’s disease. Of these, Wnt7b was upregulated and found in close association with both α-SMA and β-catenin expressing cells, making it a candidate pro-fibrotic mediator in Dupuytren’s disease.  相似文献   

4.
Molecular Biology Reports - Among different pathological mechanisms, neuronal loss and neurogenesis impairment in the hippocampus play important roles in cognitive decline in Alzheimer’s...  相似文献   

5.
In 7–8 and 9–10-years old children, we studied event-related potentials (ERPs) during paired comparison of non-verbalizable visuospatial stimuli presented at an interval of 1.5–1.8 s. Age-related differences were found in the involvement of various cortical areas in the formation and retention of a short-term memory trace of the reference stimulus and during comparison of the short-term trace with the test stimulus presented. In both age groups, working memory was associated with an elevation of the amplitude of the sensory-specific N1 component in the visual cortical areas. Age-related differences in the processing of sensory-specific characteristics of a stimulus were the greatest in the ERPs to the test stimulus: at the age of 9–10, the N1 component amplitude was significantly increased in all caudal leads and, in the occipital and inferior temporal leads, this component was preceded by P1 component. At this age, we observed the early involvement of the inferior frontal cortex, which was not observed at the age of seven. The increase in positivity over that area was observed in the interval of 100–200 ms. Substantial differences between age groups were found in the late ERP component corresponding to cognitive processes. At the age of 7–8, the presentation of both the reference and test stimuli causes the increase in the amplitude of the slow positive complex (SPC) in the caudal liads with the maximum enhancement found in the interval of 300–800 ms in the parietal leads. At the age of 9–10, the SPC increase, much like in adults, was observed in ERP to the test stimulus only. At this age, adult-like specific changes in the late phases of ERPs were observed in the fronto-central regions at the different stages of working memory. They are the increases in the negative N400 wave in the ERP to the reference stimulus and the SPC to the test stimulus. These data show that, at the age of 9–10, the functional organization of working memory of the adult type is formed; however, the extent to which the frontal cortex, and its dorsal regions in particular, is involved into working memory processes does not meet yet a definitive level.  相似文献   

6.
7.
Due to its public popularity, ornithology has a huge corpus of scientific publication for a relatively small number of species. Although there are global checklists of currently recognised taxa, there has been only limited, mainly individual, effort to build a nomenclatural database that the science of ornithology deserves. This is especially true in relation to concise synonymies. With the arrival of ZooBank and the Biodiversity Heritage Library, the time has come to develop synonymies and to add fuller bibliographic detail to databases. The preparation for both began at the start of the 20th century with extensive work by Sherborn and Richmond. I discuss their legacy, offer notes on significant work since then, and provide suggestions for what remains to be done. To make solid the foundations for ornithological nomenclature and taxonomy, especially for synonymies, ornithologists will need to collaborate much more and contribute to the digital infrastructure.  相似文献   

8.
This article explores the development of psychiatric institutions within the context of British colonial rule in India, in particular during the late nineteenth and early twentieth centuries. Existing scholarship on ‘colonial medicine’ has tended to focus on colonial power and hegemony and the British endeavour to ‘colonize the Indian body’ during the nineteenth century. It is suggested here that reference to ‘colonial’ medicine and psychiatry tends to reify the ideology of colonialism and neglect other important dimensions such as the role of international scientific networks and the mental hospital as the locus of care and medicalization. From the later period of British colonial engagement in south Asia, people’s right and entitlement to medical care and the colonial state’s obligation to provide institutional treatment facilities received increased attention. As the early twentieth-century case of an Indian hospital superintendent shows, practitioners’ professional ambitions went beyond the confines of ‘colonial psychiatry’. He practiced in his institution science-based psychiatry, drawing on models and treatment paradigms that were then prevalent in a variety of countries around the globe.  相似文献   

9.
This paper focuses on the structural development of institution-based interest in genetics in Anglo-North American medicine after 1930 concomitantly with an analysis of the changes through which ideas about heredity and the hereditary transmission of diseases in families have passed. It maintains that the unfolding relationship between medicine and genetics can best be understood against the background of the shift in emphasis in conceptualisations of recurring patterns of disease in families from ‘biological relatedness’ to ‘related to chromosomes and genes’. The paper begins with brief considerations of the historical confluences of, first, heredity and medicine and, second, genetics and medicine which, in a third section, leads to a discussion about a uniquely ‘genetics-based approach’ to medicine in the second half of the twentieth century.  相似文献   

10.
Michurinist biology was introduced to China in 1948; granted a state supported monopoly in 1952; and reduced to parity with western genetics from 1956. The Soviets exported it through the propaganda agencies Sino Soviet Friendship Association (SSFA) and VOKS (Cultural Relations with Foreign Countries). China’s Ministry of Agriculture achieved broad public awareness and acceptance of Michurinist biology through a translation, publication, and Soviet guest speakers campaign – all managed by a team of agriculturalists led by Luo Tianyu, a veteran CCP (Communist Party) cadre. The campaign grew exponentially, but did not affect university or Chinese Academy of Sciences biology. Luo Tianyu’s failed attempt to force Michurinist biology on a Beijing university triggered its second stage: monopoly status and a ban on “Mendelist-Morganist” biology in teaching, research, and publication. The CCP Central Committee supported this policy believing that Michurinst biology would increase agricultural production for the forthcoming first Five Year Plan; whereas, western genetics had no practical value. Michurinist biology flourished at all levels of education, research, and science literature; Western genetics was completely shut down. This only began to change when the CCP Central Committee became wary of China’s dependency on Soviet technical expertise and failure to fully utilize that of China. Change was further promoted by significant attacks on Michurinist biology by Soviet and East German biologists. Soon, these developments informed China’s “genetics question,” which became a test case for larger questions about the definition of science and the relationship between scientists and the state. Under the guidance of Lu Dingyi’s Central Committee Propaganda Department, the CCP eventually decided that, henceforth, science controversies would only be resolved by the science community; and that monopolies or ideological orthodoxies would not be imposed on science. At the same time, the CCP rescinded Michurinist biology’s monopoly and the ban on western genetics. By the mid-1960s western genetics had successfully restored itself, largely due to the leadership of C. C. Tan, a former student of Dobzhansky. Michurinist biology’s presence shrank and it became marginalized.  相似文献   

11.
When, in the 1980s, Alzheimer's disease became a disease of major public concern, 'personhood' also became an important, related topic of discussion. Those in caring professions (psychology, social work, etc.) and caregiver groups advocated for the 'person within' who was getting lost in a forgetful body and in a reductionist biomedical system. This essay aims to critically approach the dualism of this kind of argument by focusing on the moral positioning of claims such as personhood or biomedical reductionism.  相似文献   

12.
13.
《新西兰生态学杂志》2011,34(1):185-194
This paper explores distribution patterns exhibited by New Zealand?s freshwater fish fauna, bothfossil and extant, and seeks to clarify processes that have generated these patterns. Knowledge of a Miocene New Zealand terrestrial/freshwater fossil fauna is based substantially on lacustrine deposits in Central Otago. It reflects an ecologically very different fauna from that known today. Nothing is known of the Miocene fluvial fauna. Present-day patterns of distribution and diversity reflect a deep ecological dichotomy. About half the fauna is diadromous, and the habit of these species, of moving to and from the sea, provides them with great resilience in the face of major known landscape perturbations resulting from orogeny and land submergence, glaciation and volcanism. The diadromous species tend to be widespread throughout New Zealand. In contrast, non-diadromous species are more strictly confined to freshwater habitats, and a major means of spread relates to changes in directions and connections of stream flows. As a result, species are much less resilient, they exhibit complex patterns of sympatry, and their ranges are much more localised. Despite all elements in the fauna living across the same landscape in space and time, distribution patterns of the varying species groups display great differences in pattern.  相似文献   

14.
Most bacteria of the genus Burkholderia are soil- and rhizosphere-associated, and rhizosphere associated, noted for their metabolic plasticity in the utilization of a wide range of organic compounds as carbon sources. Many Burkholderia species are also opportunistic human and plant pathogens, and the distinction between environmental, plant, and human pathogens is not always clear. Burkholderia phages are not uncommon and multiple cryptic prophages are identifiable in the sequenced Burkholderia genomes. Phages have played a crucial role in the transmission of virulence factors among many important pathogens; however, the data do not yet support a significant correlation between phages and pathogenicity in the Burkholderia. This may be due to the role of Burkholderia as a 'versaphile' such that selection is occurring in several niches, including as a pathogen and in the context of environmental survival.  相似文献   

15.
During the 1840s, physicians from the Habsburg Empire played a decisive role in the reform of medical structures in the Ottoman Empire. This paper discusses different aspects of this scientific and cultural encounter. It emphasizes the importance of Austrian health care structures as a model for the work of these physicians in the Ottoman Empire and studies the role of the medical school ran by the Austrians as a means of representing, on the one hand, the reformatory efforts of the Ottoman Empire and, on the other hand, the motivations of the Habsburg monarchy for an involvement in Ottoman health care affairs, strongly bound up with its own quarantine politics towards the Ottoman Empire.  相似文献   

16.
Journal of Ichthyology - Interannual dynamics of the integral characteristics of species structure in the fish community in the Pacific waters off the Kuril Islands in 2004–2018 is described....  相似文献   

17.
Despite the amount of work that has been produced on the subject over the years, the ‘transformation of cladistics’ is still a misunderstood episode in the history of comparative biology. Here, I analyze two outstanding, highly contrasting historiographic accounts on the matter, under the perspective of an influential dichotomy in the philosophy of science: the opposition between Scientific Realism and Empiricism. Placing special emphasis on the notion of ‘causal grounding’ of morphological characters (sensu Olivier Rieppel) in modern developmental biology’s (mechanistic) theories, I arrive at the conclusion that a ‘new transformation of cladistics’ is philosophically plausible. This ‘reformed’ understanding of ‘pattern cladistics’ entails retaining the interpretation of cladograms as ‘schemes of synapomorphies’, but in association to construing cladogram nodes as ‘developmental-genetic taxic homologies’, instead of ‘standard Darwinian ancestors’. The reinterpretation of pattern cladistics presented here additionally proposes to take Bas Van Fraassen’s ‘constructive empiricism’ as a philosophical stance that could properly support such analysis of developmental-genetic data for systematic purposes. The latter suggestion is justified through a reappraisal of previous ideas developed by prominent pattern cladists (mainly, Colin Patterson), which concerned a scientifically efficient ‘observable/non-observable distinction’ linked to the conceptual pair ‘ontogeny and phylogeny’. Finally, I argue that a robust articulation of Antirealist alternatives in systematics may provide a rational basis for its disciplinary separation from evolutionary biology, as well as for a critical reconsideration of the proper role of certain Scientific Realist positions, currently popular in comparative biology.  相似文献   

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19.
This article argues for a public sociology of ‘race’ that can respond to Weber's injunction that sociology should ‘meet the demands of the day’. While the author's version of these demands – for a society of autonomous individuals and groups, living as equals – is utopian, the main argument offered here is that a sociology of ‘race’ should be a modified version of Burawoy's ‘public sociology’. Adopting Bauman's notion of a sociology of interpreters, a further suggestion is that this type of sociology needs to be reflexive and affective. Based on an analysis of his own sociological education in the late 1960s, his participation in social and political movements in which ‘race’ was key, and with brief reference to the sociology of ‘race’, the author argues that the emotions that circulated in each arena need to be examined, acknowledged and incorporated if theoretical and practical progress is to be made.  相似文献   

20.
Russian Journal of Developmental Biology - Auxin is an important inductor of organogenesis. During leaf development, local sites with high auxin concentration initiate the formation of leaf...  相似文献   

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