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1.
Piccolino M 《Endeavour》1999,23(4):175-179
All his life, Marcello Malpighi (1628–1694), the founder of modern microscopic anatomy, was unwillingly involved in difficult debates within a reactionary medical milieu that questioned the significance of modern science and its utility to medicine. Malpighi's responses to his detractors, included in posthumous works first published in 1697 by the Royal Society, offer an important insight into a critical phase of scientific progress in the 17th century and help to reveal the prevailing conception of science. In some ways, Malpighi's views predate important ideas in modern biology.  相似文献   

2.
The biotechnological exploitation of fungi is becoming more and more important both for industrial purposes and in the field of cultivation of edible mushrooms. In the past, breeding of fungi was restricted mainly to selection of better strains after spontaneous or induced mutations. Today, the inclusion of genetic recombination—based on better knowledge of how to handle fungi under controlled conditions, of their life cycles, and of their breeding systems—has given the possibility of ‘concerted breeding’. In addition, some recent basic research provides means of preventing ageing and death of fungal strains, by either genetic alterations or therapeutic treatment. Examples of the application of these ideas and results are given.  相似文献   

3.
C. Brotman 《Endeavour》2001,25(4):144
In the years after the publication of Darwin's On the Origin of Species, Alfred Russel Wallace became a prominent critic of the argument that evolution provided a sufficient account of human origins. Unbeknownst to many historians of science, Wallace partly based his case on his belief that man's musical sense and aesthetic powers could not have evolved by natural selection. Although he witnessed a variety of musical practices during his travels abroad, Wallace, like many contemporaries in Victorian England, assumed that music uniquely belonged to the ‘civilized’ world he inhabited. In the late 19th century, some evolutionists would challenge this view by reconceiving the nature of music itself.  相似文献   

4.
5.
Mitchell S 《Endeavour》2003,27(4):150-154
Chang and Eng, the two young men who would eventually be known around the world as the ‘original’ Siamese twins, arrived in the West in 1829. They were brought to the West to be examined by medical men and to be exhibited to the general public. Throughout the 19th century in Britain and the US, ‘monstrosities’ such as Chang and Eng, as well as a host of other people with unusual anatomies, were considered both spectacles worthy of public display and edifying medical subjects with the potential to build on medical knowledge. The unique case of Chang and Eng illustrates that the boundary between what is of legitimate medical interest and what is considered merely spectacle is often blurred.  相似文献   

6.
Spary EC 《Endeavour》1999,23(4):180-183
During the 18th century, the reinvention of French surgery as a ‘monarchical profession’, in the words of Toby Gelfand, enabled the creation of an elite surgical knowledge from which uninstructed participants could be excluded. A link can be made between the types of resources used by surgeons to present themselves as expert healers, and the epistemological strategies of the operation. The sickbed was the scene of a performance, in which every actor's movements were described and constrained; the end product of an extended process of social negotiation, surgical training, physical restraint and submission.  相似文献   

7.
The need for collaborative ventures in Europe has long been stressed in the editorial pages of this journal, and more than ten years ago (Endeavour, 28, 54, 1969) we gave strong support for a proposal to establish a European Laboratory of Molecular Biology. For this we then incurred some criticism, on the ground that such a laboratory would weaken national academic institutes striving to establish themselves in this rapidly developing field. Nevertheless, we continued to maintain (30, 2, '71) ‘the great political and scientific importance of this [concept]—and of other such collaborative enterprises—if Europe is to maintain the initiative in fields where the great institutions of the United States have established a dominant position.’ In the event, the Laboratory was established at Heidelberg in 1974, though not formally opened until 1978. The Director-General, Sir John Kendrew, here surveys the policy and achievements of this important new institute.  相似文献   

8.
Of the animal artifacts encountered by archaeologists, bones and teeth are the ones most commonly found. Systematic study of these — particularly of their distribution and the different species involved —can throw much light on the diet and eating habits of people in the past.  相似文献   

9.
The acute renal failure is the frequent medical complication observed in liver transplant patients. The objective of this study was to determine the cause of acute renal failure in post liver transplant patients. A total of 70 patients who underwent (cadaveric 52, live 18) liver transplantation were categorized based on clinical presentation into two groups, namely hepatorenal failure (HRF, n = 29), and Hepatic failure (HF, n = 41). All the patients after the liver transplant had received tacrolimus, mycophenolate and steroids. We analyzed the modification of diet in renal disease, (MDRD) serum urea, creatinine and albumin before and after 5th and 30th day of liver transplant and data was categorized into survivors and non-survivors group. In HRF survivor group, serum creatinine, and urea levels were high and, albumin, MDRD were low in pre- transplant and reached to normal levels on 30th day of post transplant, and 79.3 % of patients in this group showed resumption of normal kidney function. On the contrary in HRF nonsurvivor group, we did not observed any significant difference and 20.7 % of patients showed irreversible changes after the liver transplant. In HF survivor group, 82.9 % of liver failure patients did not show any deviation in serum creatinine, urea, albumin and MDRD, whereas in HF non survivor group, 17.1 % of liver failure patients who had HCV positive before the transplant developed acute renal failure. The levels of creatinine, urea, albumin and MDRD were normal before the transplant and on day 30th, the levels of albumin and MDRD were significantly low whereas serum urea, creatinine levels were high. In conclusion, based on these observations, an diagnosis and treatment of Acute renal failure is important among the liver transplantation cases in the early postoperative period.  相似文献   

10.
To study oxidative stress in systemic lupus erythematosus (SLE) by estimating serum oxidised LDL (OxLDL), 8-hydroxy-2′-deoxyguanosine (8-OHdG), malondialdehyde (MDA), and total anti-oxidant status and to correlate with SLE disease activity and disease damage. Eighty SLE patients satisfying the Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) 2012 criteria and 80 healthy controls were studied. Exclusion criteria were infections, renal insufficiency, other connective tissue diseases, drug-induced lupus, smoking, alcohol consumption. Disease activity was measured by SLE disease activity index-2 K (SLEDAI), disease damage was quantified by SLICC-Damage Index (SDI). Sera was tested for OxLDL, 8-OHdG, and total antioxidant status (TAS) by double-antibody sandwich ELISA; MDA measured by Colorimetric assay. Oxidative stress markers were compared between group1- controls, group 2-mildly active SLE (SLEDAI ≤ 5), group 3- moderate to highly active SLE (SLEDAI ≥ 6). SLE patients had significantly higher MDA, 8-OHdG and lower TAS when compared to healthy controls, while OxLDL was similar in the three groups. MDA, 8-OHdG were significantly higher, TAS lower in group 3 compared to group 2. MDA had positive correlation with SLEDAI, TAS negatively correlated with SLEDAI. SLE with neuropsychiatric manifestations, vasculitis, anti-sdDNA antibodies had higher MDA, MDA/TAS ratio. SLE patients with thrombocytopenia, and vasculitis had higher OxLDL. Only OxLDL was significantly higher in those patients who have SDI > 1. SLE patients have increased oxidative stress measured by increases in MDA, 8-OHdG, and lower total antioxidant status that was associated with disease activity and some disease manifestations. However only OxLDL was associated with damage.  相似文献   

11.
The Harappan civilization, the world's fourth great civilization after those of Egypt, Mesopotamia, and China flourished in the valley of the Indus three thousand years ago. As yet little is known about it, but one enormous town — Mohenjo-Daro — has survived. This has been only partially excavated and has yielded just a few scraps of information which have provided the basis for some fanciful theories. The author of this article had developed an interesting new approach. Combining a re-examination of the documentation that has accumulated over the past 50 years with an investigation of the actual remains, he has obtained some exciting results which shed new light on the overall planning, architecture, and development of the town over the centuries, thus providing a fresh understanding of the Harappan civilization itself.  相似文献   

12.
Isolated mitochondria display a wide range of sizes plausibly resulting from the coexistence of subpopulations, some of which may be associated with disease or aging. Strategies to separate subpopulations are needed to study the importance of these organelles in cellular functions. Here, insulator-based dielectrophoresis (iDEP) was exploited to provide a new dimension of organelle separation. The dielectrophoretic properties of isolated Fischer 344 (F344) rat semimembranosus muscle mitochondria and C57BL/6 mouse hepatic mitochondria in low conductivity buffer (0.025–0.030 S/m) at physiological pH (7.2–7.4) were studied using polydimethylsiloxane (PDMS) microfluidic devices. First, direct current (DC) and alternating current (AC) of 0–50 kHz with potentials of 0–3000 V applied over a channel length of 1 cm were separately employed to generate inhomogeneous electric fields and establish that mitochondria exhibit negative DEP (nDEP). DEP trapping potential thresholds at 0–50 kHz were also determined to be weakly dependent on applied frequency and were generally above 200 V. Second, we demonstrated a separation scheme using DC potentials <100 V to perform the first size-based iDEP sorting of mitochondria. Samples of isolated mitochondria with heterogeneous sizes (150 nm–2 μm diameters) were successfully separated into sub-micron fractions, indicating the ability to isolate mitochondria into populations based on their size.  相似文献   

13.
This paper presents a taxonomy of entrepreneurial behaviour vis-à-vis technology, derived from empirical research on a specific sector, that of the chemicals industry in Venezuela. The research focuses heavily on the accumulation of minor innovations through which enterprises acquire their technical knowledge and know how, their technological learning. We have tried to give a precise empirical meaning to that notion in order to understand which are the most important variables that affect the technical learning process. Both the process of technological learning and the technical external linkages — in particular with foreign firms — of Venezuelan companies seem to be the fundamental factors in understanding the development of a new competitive industry which adopts a new products-oriented strategy. But not all firms do respond to such a scheme and it is thus necessary to develop a taxonomy of the industrial sector both for scholarly reasons as well as a policy guide.  相似文献   

14.
王秀芬 《科学学研究》2006,24(Z1):59-61
在人类文明进程的各类灾害中,瘟疫给人类社会造成的威胁巨大。在20世纪仅天花就夺走3亿人的生命,相当于该世纪发生的所有战争死亡人数的3倍以上。随着艾滋病、疯牛病、埃博拉病毒、SARS特别是当下高致病性禽流感的流行和肆虐,人类在确保生命安全公众健康,促进经济社会协调发展,推动人与自然和谐相处,以及科学预防控制传染疾病的旅途中任重道远,仍需要精诚协作和协同攻关。  相似文献   

15.
Drawing on institutional theory, we examine how institutions have influenced technology development trends in the U.S. since the mid-19th century. Based on an inductive analysis of the history of technology development and corporate R&D, we show that both formal and informal institutional rules and constraints played a role in the initial rise of markets for technology, their decline during the early-20th century, and their eventual return at the end of the 20th century. We also find that formal and informal institutions influenced the widespread adoption of in-house R&D labs during the mid-20th century. Our study integrates insights from both the economics and sociology branches of institutional theory. This perspective is particularly useful to analyze historical phenomenon and shifts in trends across long time periods.  相似文献   

16.
By introducing the concept of innovation regimes, the aim of this article is to show how the rapid pace of technological development in the telecom sector may be explained by the close links between the sector's own R&D and the creation of numerous innovations, many of which are radical. In contemporary innovation theory, a theoretical antinomy exists: Whereas, the creation of incremental innovations is variously explained in terms of «rational» responses to markets, dynamics of technological regimes, dominant design, etc., radical innovations, in contrast, are explained in terms of serendipity, chance or haphazard scientific discoveries. Evidence from analysis of innovations in the telecom sector suggests that innovation regimes have provided a capability of coordination, direction and leadership in the creation of many of the radical technological innovations that have emerged in the sector. Thus, one may claim that the strong innovation regimes and high R&D intensity of the telecom sector, at least until recently, have provided a capability of creating innovations on purpose — for a purpose. The policy implications of this contradict some of the assumptions on which the prevailing market-oriented R&D governance models and policies are based — and which are supported by contemporary innovation theories.  相似文献   

17.
Of all the senses, that of taste is perhaps the hardest to define and quantify and elucidation of the underlying mechanisms is unrespondingly difficult. This article describes a conceptual model — at the molecular level — for the four basic taste modalities, using apparent specific volume as a fundamental parameter. It also considers possible practical applications.  相似文献   

18.
Establishing the microfoundations of academic entrepreneurship requires closer scrutiny of a key actor contributing to this phenomenon—the university scientist. We investigate the sense-making that scientists engage in as part of their participation in technology transfer and postulate that this process involves a potential modification in their role identity. We analyzed more than 70 h of interview data at a premier U.S. public research university. We observe that scientists invoke rationales for involvement that are congruent with their academic role identity. They typically adopt a hybrid role identity that comprises a focal academic self and a secondary commercial persona. We delineate two mechanisms – delegating and buffering – that these individuals deploy to facilitate such salience in their hybrid role identity. Overall, these patterns suggest that university scientists take active steps to preserve their academic role identity even as they participate in technology transfer. Our findings clarify the social psychological processes underlying scientist involvement in commercialization activity, and offer fresh insights to the academic entrepreneurship, science policy and role identity literatures.  相似文献   

19.
Croplands are the single largest anthropogenic source of nitrous oxide (N2O) globally, yet their estimates remain difficult to verify when using Tier 1 and 3 methods of the Intergovernmental Panel on Climate Change (IPCC). Here, we re-evaluate global cropland-N2O emissions in 1961–2014, using N-rate-dependent emission factors (EFs) upscaled from 1206 field observations in 180 global distributed sites and high-resolution N inputs disaggregated from sub-national surveys covering 15593 administrative units. Our results confirm IPCC Tier 1 default EFs for upland crops in 1990–2014, but give a ∼15% lower EF in 1961–1989 and a ∼67% larger EF for paddy rice over the full period. Associated emissions (0.82 ± 0.34 Tg N yr–1) are probably one-quarter lower than IPCC Tier 1 global inventories but close to Tier 3 estimates. The use of survey-based gridded N-input data contributes 58% of this emission reduction, the rest being explained by the use of observation-based non-linear EFs. We conclude that upscaling N2O emissions from site-level observations to global croplands provides a new benchmark for constraining IPCC Tier 1 and 3 methods. The detailed spatial distribution of emission data is expected to inform advancement towards more realistic and effective mitigation pathways.  相似文献   

20.
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