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1.
The German biologist Julius Sachs was the first to introduce controlled, accurate, quantitative experimentation into the botanical sciences, and is regarded as the founder of modern plant physiology. His seminal monograph Experimental-Physiologie der Pflanzen (Experimental Physiology of Plants) was published 150 y ago (1865), when Sachs was employed as a lecturer at the Agricultural Academy in Poppelsdorf/Bonn (now part of the University). This book marks the beginning of a new era of basic and applied plant science. In this contribution, I summarize the achievements of Sachs and outline his lasting legacy. In addition, I show that Sachs was one of the first biologists who integrated bacteria, which he considered to be descendants of fungi, into the botanical sciences and discussed their interaction with land plants (degradation of wood etc.). This “plant-microbe-view” of green organisms was extended and elaborated by the laboratory botanist Wilhelm Pfeffer (1845–1920), so that the term “Sachs-Pfeffer-Principle of Experimental Plant Research” appears to be appropriate to characterize this novel way of performing scientific studies on green, photoautotrophic organisms (embryophytes, algae, cyanobacteria).  相似文献   

2.
Cancer as one of the most important human diseases does not present as formidable a problem as infectious disease did a century ago. The diversified cancer program, combining voluntary and governmental agencies in support of research, education and coordinated teamwork in the clinical care of the patient, presents a varied although unified approach to the problem that has never before been available for the study of any single human disease. Pathology, with its applied methods from the basic sciences, has a singular role in the scientific aspect of the cancer program. Representing a new specialty in medicine and embodying an inquiring approach to the study of human disease, pathology has a leading role to play. The pathologist, assuming the new role of “pathologist-physician” brings to the clinical care of the cancer patient the most precise methods of cancer diagnosis. The “pathologist-physician” should be a pivotal member of the “clinical team” in the immediate diagnosis, care and treatment of the cancer patient.  相似文献   

3.
The hypothesis of a Hierarchy of the Sciences with physical sciences at the top, social sciences at the bottom, and biological sciences in-between is nearly 200 years old. This order is intuitive and reflected in many features of academic life, but whether it reflects the “hardness” of scientific research—i.e., the extent to which research questions and results are determined by data and theories as opposed to non-cognitive factors—is controversial. This study analysed 2434 papers published in all disciplines and that declared to have tested a hypothesis. It was determined how many papers reported a “positive” (full or partial) or “negative” support for the tested hypothesis. If the hierarchy hypothesis is correct, then researchers in “softer” sciences should have fewer constraints to their conscious and unconscious biases, and therefore report more positive outcomes. Results confirmed the predictions at all levels considered: discipline, domain and methodology broadly defined. Controlling for observed differences between pure and applied disciplines, and between papers testing one or several hypotheses, the odds of reporting a positive result were around 5 times higher among papers in the disciplines of Psychology and Psychiatry and Economics and Business compared to Space Science, 2.3 times higher in the domain of social sciences compared to the physical sciences, and 3.4 times higher in studies applying behavioural and social methodologies on people compared to physical and chemical studies on non-biological material. In all comparisons, biological studies had intermediate values. These results suggest that the nature of hypotheses tested and the logical and methodological rigour employed to test them vary systematically across disciplines and fields, depending on the complexity of the subject matter and possibly other factors (e.g., a field''s level of historical and/or intellectual development). On the other hand, these results support the scientific status of the social sciences against claims that they are completely subjective, by showing that, when they adopt a scientific approach to discovery, they differ from the natural sciences only by a matter of degree.  相似文献   

4.
W. Desmond Henry  Alan M. Mann 《CMAJ》1965,93(22):1156-1166
Delirium is not a clinical entity but a symptom-complex of manifold etiology. Its presence signifies acute cerebral insufficiency and often represents a medical and/or psychiatric emergency.Though some forms of delirium have distinctive features, the fundamental phenomena are common to all, with clouding of consciousness the sine qua non. The condition has two major components: (1) the basic “acute brain syndrome” and (2) associated release phenomena.Clinicians must first make the vital differentiation between delirium and “functional” mental disorder, then proceed with the elucidation of the underlying diagnosis and the concurrent organization of symptomatic and etiologic treatment.Proper treatment combines management of the acute brain syndrome with general and specific procedures for control of the underlying condition. Dealing with the symptom-complex itself involves the principles and practice of sedation, hydration, and nutrition, nursing care and supportive measures. Provided the basic organic condition is treatable, the prognosis today is usually good.  相似文献   

5.
The theme of the 2013 Yale Healthcare Conference was “Partnerships in Healthcare: Cultivating Collaborative Solutions.” The April conference brought together leaders across several sectors of health care, including academic research, pharmaceuticals, information technology, policy, and life sciences investing. In particular, the breakout session titled “Taking R&D Back to School: The Rise of Pharma-Academia Alliances” centered on the partnerships between academic institutions and pharmaceutical companies. Attendees of the session included members of the pharmaceutical industry, academic researchers, and physicians, as well as graduate and professional students. The discussion was led by Dr. Thomas Lynch of Yale University. Several topics emerged from the discussion, including resources for scientific discovery and the management of competing interests in collaborations between academia and the pharmaceutical industry.  相似文献   

6.
The hypothesis of a Hierarchy of the Sciences, first formulated in the 19th century, predicts that, moving from simple and general phenomena (e.g. particle dynamics) to complex and particular (e.g. human behaviour), researchers lose ability to reach theoretical and methodological consensus. This hypothesis places each field of research along a continuum of complexity and “softness”, with profound implications for our understanding of scientific knowledge. Today, however, the idea is still unproven and philosophically overlooked, too often confused with simplistic dichotomies that contrast natural and social sciences, or science and the humanities. Empirical tests of the hypothesis have usually compared few fields and this, combined with other limitations, makes their results contradictory and inconclusive. We verified whether discipline characteristics reflect a hierarchy, a dichotomy or neither, by sampling nearly 29,000 papers published contemporaneously in 12 disciplines and measuring a set of parameters hypothesised to reflect theoretical and methodological consensus. The biological sciences had in most cases intermediate values between the physical and the social, with bio-molecular disciplines appearing harder than zoology, botany or ecology. In multivariable analyses, most of these parameters were independent predictors of the hierarchy, even when mathematics and the humanities were included. These results support a “gradualist” view of scientific knowledge, suggesting that the Hierarchy of the Sciences provides the best rational framework to understand disciplines'' diversity. A deeper grasp of the relationship between subject matter''s complexity and consensus could have profound implications for how we interpret, publish, popularize and administer scientific research.  相似文献   

7.
Meiosis in eggs of Tetranychus urticae Koch is described. The two maturation divisions result in (a) a haploid female pronucleus consisting of three karyomeres; — (b) a divided first polar body in which the chromosomes change into karyomeres; — (c) a second polar body, entering a new mitosis which is blocked in metaphase. Irradiation of adult females produced chromosome fragments in the meiotic divisions. The fragments behave as intact chromosomes which proves that during meiosis a diffuse kinetochore is present. The meiotic divisions show the cytologically characteristic features of an inverted meiosis. The presence of such a meiosis is corroborated by observations on eggs heterozygous for chromosome mutations. In both maturation divisions the chromosomes are orientated equatorially. It is suggested that the equatorial orientation is brought about by chiasmata having terminalized to both ends of the dyads. It is argued that in organisms with holokinetic chromosomes during meiosis an axial orientation of the bivalents does not necessarily imply a normal meiosis but can also imply an inverted meiosis.This work was carried out with financial aid of the Institute for Atomic Sciences in Agriculture and the Ministry of Public Health and Environment.  相似文献   

8.
Harvard Medical School convened a meeting of biomedical and clinical experts on 5 March 2015 on the topic of “Rethinking the Response to Emerging Microbes: Vaccines and Therapeutics in the Ebola Era,” with the goals of discussing the lessons from the recent Ebola outbreak and using those lessons as a case study to aid preparations for future emerging infections. The speakers and audience discussed the special challenges in combatting an infectious agent that causes sporadic outbreaks in resource-poor countries. The meeting led to a call for improved basic medical care for all and continued support of basic discovery research to provide the foundation for preparedness for future outbreaks in addition to the targeted emergency response to outbreaks and targeted research programs against Ebola virus and other specific emerging pathogens.  相似文献   

9.
10.
In May 2012, Yale University’s Graduate School of Arts and Sciences held a reunion for all who have received doctorates from Yale in the biological sciences. The proceedings began with two presentations on the history of biological research at Yale: one focused on the Medical School, and the other centered on the rest of the University. This essay is a lightly edited version of my account of the history of the biological sciences outside the Medical School.  相似文献   

11.
In the past two decades, our ability to study cellular and molecular systems has been transformed through the development of omics sciences. While unlimited potential lies within massive omics datasets, the success of omics sciences to further our understanding of human disease and/or translating these findings to clinical utility remains elusive due to a number of factors. A significant limiting factor is the integration of different omics datasets (i.e., integromics) for extraction of biological and clinical insights. To this end, the National Cancer Institute (NCI) and the National Heart, Lung and Blood Institute (NHLBI) organized a joint workshop in June 2012 with the focus on integration issues related to multi-omics technologies that needed to be resolved in order to realize the full utility of integrating omics datasets by providing a glimpse into the disease as an integrated “system”. The overarching goals were to (1) identify challenges and roadblocks in omics integration, and (2) facilitate the full maturation of ‘integromics’ in biology and medicine. Participants reached a consensus on the most significant barriers for integrating omics sciences and provided recommendations on viable approaches to overcome each of these barriers within the areas of technology, bioinformatics and clinical medicine.  相似文献   

12.
The physiological disciplines are being taught from the 1st year of medical study up to the end of the 4th year, it means 8 semesters altogether. It is necessary to explain the curriculum of the 3rd Faculty of Medicine, Charles University in Prague. This Faculty has had a new curriculum since 1997, so the first students, who had been taught as to this system, already finished their study. The duration of medical study is 6 years, i.e. 12 semesters. This composed of three cycles: I Basic biomedical sciences. The first two years represent the first cycle, which is based on the integrative principle. II. Principles of clinical medicine. The second cycle is concerned on the problem-based learning. III. Clinical preparation. The third cycle represents clinical application. In the first two years the integrative study is composed of different modules. The first module I A--Structure and functions of human body is the greatest module in the first two years, which is composed of anatomy, histology and embryology, biochemistry and physiology. The module I B--Cell biology and genetics is composed of genetics and cell biology and this module is finished by the examination after two semesters at the end of the first year.  相似文献   

13.
In this brief review, Dr. Jonathan Borak comments on five seminal papers that helped shape the fields of epidemiology and public health. These papers include Hill’s criteria for inferring causality; the first proof of the multistage theory of cancer; the first evidence that subclinical lead exposures can cause neurobehavioral impairment in children; a simple yet robust study that had a major influence on setting current air pollution policies; and a landmark review of the general public’s perception of risk in relation to actual public health hazard.Dr. Jonathan Borak is a Clinical Professor of Epidemiology and Public Health at the Yale School of Public Health, Clinical Professor of Internal Medicine at the Yale School of Medicine, and Director of the Yale Interdisciplinary Risk Assessment Forum. In this article, Dr. Borak provides his perspective on five publications that significantly influenced the study and practice of epidemiology and public health. This article is the first in a series that will identify and provide commentary on the top five seminal papers published in a field related to biology and medicine.A former student, a member of the Yale Journal of Biology and Medicine’s Editorial Board, reminded me of a comment I made in class. I had described a particular assigned reading as “one of those classic articles” that should be read by everyone studying public health. Okay, he challenged me, what other “classic articles” were on my list? And so began the following: my short list of five articles that represent “must reading” for all students in public health.First, note that I do not speak for public health in general, a field of great breadth of interest and activity, but only the narrower slice, including toxicology, risk assessment, and related interests. Also, I was principally concerned to identify articles that provide models of critical thinking, addressed issues of substantial public health importance, and served as stepping stones for subsequent research and the formulation of public health policy. I also wanted to include articles that were observational and opportunistic, i.e., based on real world observations and available data, not complex laboratory models.My five choices below include: 1) a landmark presentation of criteria for inferring causality from observational data (Hill 1965); 2) a thought experiment based on the re-analysis of publicly available cancer mortality data, which shaped the fields of cancer biology and risk assessment (Armitrage & Doll, 1954); 3) an early study of the effects of lead exposure in school children (Needleman, 1979); 4) a study of the impact of air pollution on children’s health, which was enabled by a fortuitous labor dispute that shuttered a polluting steel mill (Ransom & Pope, 1992); and, 5) a critical literature review of cognitive psychology research that shaped our understanding about how public health risks are perceived (Slovic, 1987).  相似文献   

14.
Objective To develop and validate practical prognostic models for death at 14 days and for death or severe disability six months after traumatic brain injury.Design Multivariable logistic regression to select variables that were independently associated with two patient outcomes. Two models designed: “basic” model (demographic and clinical variables only) and “CT” model (basic model plus results of computed tomography). The models were subsequently developed for high and low-middle income countries separately. Setting Medical Research Council (MRC) CRASH Trial.Subjects 10 008 patients with traumatic brain injury. Models externally validated in a cohort of 8509.Results The basic model included four predictors: age, Glasgow coma scale, pupil reactivity, and the presence of major extracranial injury. The CT model also included the presence of petechial haemorrhages, obliteration of the third ventricle or basal cisterns, subarachnoid bleeding, midline shift, and non-evacuated haematoma. In the derivation sample the models showed excellent discrimination (C statistic above 0.80). The models showed good calibration graphically. The Hosmer-Lemeshow test also indicated good calibration, except for the CT model in low-middle income countries. External validation for unfavourable outcome at six months in high income countries showed that basic and CT models had good discrimination (C statistic 0.77 for both models) but poorer calibration.Conclusion Simple prognostic models can be used to obtain valid predictions of relevant outcomes in patients with traumatic brain injury.  相似文献   

15.
Here we report three cases of canine trypanosomosis presented to the Veterinary Teaching Hospital in the Faculty of Veterinary Medicine and Animal Sciences at the University of Peradeniya, Sri Lanka during 2018. The cases were presented to the hospital when the dogs were already in critical condition. Confirmation of the cases was done by microscopic examination of Giemsa-stained thin blood smears. All three dogs had bilateral keratitis and anterior chamber cloudiness in eyes. Despite the intramuscular administration of diminazine aceturate, all of them subsequently died. Amplification and sequencing of a fragment of the internal transcribed spacer 1 (ITS1) of the nuclear ribosomal DNA confirmed the parasite as Trypanosoma. evansi. This is the first record of clinical cases of canine trypanosomosis in Sri Lanka. The three cases reported here came from widely separated geographical locations within the country: Balangoda, Mullaitivu and Kadawatha.  相似文献   

16.
Implants are widely used in various clinical disciplines to replace or stabilize organs. The challenge for the future is to apply implant materials to specifically control the biology of the surrounding tissue for repair and regeneration. This field of research is highly interdisciplinary and combines scientists from technical and life sciences disciplines. To successfully apply materials for regenerative processes in the body, the understanding of the mechanisms at the interface between cells or tissues and the artificial material is of critical importance. The research focuses on stem cells, design of material surfaces, and mechanisms of cell adhesion. For the third time around 200 scientists met in Rostock, Germany for the international symposium “Interface Biology of Implants.” The aim of the symposium is to promote the interdisciplinary dialogue between the scientists from the different disciplines to develop smart implants for medical use. In addition, researchers from basic sciences, notably cell biology presented new findings concerning mechanisms of cell adhesion to stimulate research in the applied field of implant technology.Key words: interface, implant, stem cells, adhesion, mechanics, surface, biomaterialMedical implants play a growing role in routine clinical practice. In addition to replace or stabilize injured tissue permanently or transiently, the application of implant materials to stimulate the regeneration of tissue is becoming a challenge in the field of regenerative medicine. The use of implant materials is based on the idea that biomaterials function not only as mechanical support for cells and tissue but also provide a matrix to induce signal transduction in the cells that control complex molecular mechanisms responsible for proliferation und differentiation. In this context, the interface between artificial materials and living cells or tissue is an exciting field of great scientific interest and constitutes one of the most dynamic and expanding field in science and technology. Progress in this field is mainly driven by the fundamental importance for clinical applications. The research is characterized by a multidisciplinary collaboration between physics, engineers, biologists and clinicians.In May 2009, for the third time after 2003 and 2006 around 200 scientists met in Rostock-Warnemünde for the symposium “Interface Biology of Implants” to discuss biointerface processes at a fundamental level. The main goals of this symposium are to simulate the interdisciplinary dialogue between scientists of the different disciplines and to introduce current knowledge of basic research in cell biology and material science into the applied field of implant technology. The programme was organized in invited presentations of 20 internationally renowned scientists and complemented by short talks of mostly young scientists selected from the submitted abstracts. In addition, 80 posters presented latest results in this multidisciplinary field.The symposium was opened with a keynote lecture presented by Hartmut Hildebrand (Lille). He gave an overview about the 7,000 years old history of application of implant materials. Rare photographs were shown which demonstrated that in these early times prostheses mainly made from metallic materials were used to restore teeth, extremities and the skull of the human body. These old documents stressed the historical relevance of medical application of implant materials.The symposium on two days was composed of four sessions covering the interdisciplinary research in the field. The session “Stem cells and biomaterials” discussed the biological response and signalling mechanism of stem cells in the interaction with a material surface. The session “Bioactivation of implant surfaces” focussed on the tailoring of surfaces to control the cell physiology. To stimulate the field by recent data in basic cell biology, talks were presented in the third session, dealing with molecular mechanisms involved in cell adhesion. A special session dealt with the role and mechanism of controlling cells by mechanics.  相似文献   

17.
Health literacy (HL) refers to the ability to obtain, process, and understand basic health information and services, and is thus needed to make appropriate health decisions. The Newest Vital Sign (NVS) is comprised of 6 questions about an ice cream nutrition label and assesses HL numeracy skills. We developed a Japanese version of the NVS (NVS-J) and evaluated the validity and reliability of the NVS-J in patients with chronic pain. The translation of the original NVS into Japanese was achieved as per the published guidelines. An observational study was subsequently performed to evaluate the validity and reliability of the NVS-J in 43 Japanese patients suffering from chronic pain. Factor analysis with promax rotation, using the Kaiser criterion (eigenvalues ≥1.0), and a scree plot revealed that the main component of the NVS-J consists of three determinative factors, and each factor consists of two NVS-J items. The criterion-related validity of the total NVS-J score was significantly correlated with the total score of Ishikawa et al.''s self-rated HL Questionnaire, the clinical global assessment of comprehensive HL level, cognitive function, and the Brinkman index. In addition, Cronbach''s coefficient for the total score of the NVS-J was adequate (alpha = 0.72). This study demonstrated that the NVS-J has good validity and reliability. Further, the NVS-J consists of three determinative factors: “basic numeracy ability,” “complex numeracy ability,” and “serious-minded ability.” These three HL abilities comprise a 3-step hierarchical structure. Adequate HL should be promoted in chronic pain patients to enable coping, improve functioning, and increase activities of daily living (ADLs) and quality of life (QOL).  相似文献   

18.
Self-compassion, typically operationalized as the total score of the Self-Compassion Scale (SCS; Neff, 2003b), has been shown to be related to increased psychological well-being and lower depression in students of the social sciences, users of psychology websites and psychotherapy patients. The current study builds on the existing literature by examining the link between self-compassion and depressive symptomatology in a sample representative of the German general population (n = 2,404). The SCS subscales of self-judgment, isolation, and over-identification, and the “self-coldness”, composite score, which encompass these three negative subscales, consistently differed between subsamples of individuals without any depressive symptoms, with any depressive syndromes, and with major depressive disorder. The contribution of the positive SCS subscales of self-kindness, common humanity, and mindfulness to the variance in depressive symptomatology was almost negligible. However, when combined to a “self-compassion composite”, the positive SCS subscales significantly moderated the relationship between “self-coldness” and depressive symptoms in the general population. This speaks for self-compassion having the potential to buffer self-coldness related to depression—providing an argument for interventions that foster self-caring, kind, and forgiving attitudes towards oneself.  相似文献   

19.

Background

Early diagnosis of dengue virus (DENV) infection can improve clinical outcomes by ensuring close follow-up, initiating appropriate supportive therapies and raising awareness to the potential of hemorrhage or shock. Non-structural glycoprotein-1 (NS1) has proven to be a useful biomarker for early diagnosis of dengue. A number of rapid diagnostic tests (RDTs) and enzyme-linked immunosorbent assays (ELISAs) targeting NS1 antigen (Ag) are now commercially available. Here we evaluated these tests using a well-characterized panel of clinical samples to determine their effectiveness for early diagnosis.

Methodology/Principal Findings

Retrospective samples from South America were used to evaluate the following tests: (i) “Dengue NS1 Ag STRIP” and (ii) “Platelia Dengue NS1 Ag ELISA” (Bio-Rad, France), (iii) “Dengue NS1 Detect Rapid Test (1st Generation)” and (iv) “DENV Detect NS1 ELISA” (InBios International, United States), (v) “Panbio Dengue Early Rapid (1st generation)” (vi) “Panbio Dengue Early ELISA (2nd generation)” and (vii) “SD Bioline Dengue NS1 Ag Rapid Test” (Alere, United States). Overall, the sensitivity of the RDTs ranged from 71.9%–79.1% while the sensitivity of the ELISAs varied between 85.6–95.9%, using virus isolation as the reference method. Most tests had lower sensitivity for DENV-4 relative to the other three serotypes, were less sensitive in detecting secondary infections, and appeared to be most sensitive on Day 3–4 post symptom onset. The specificity of all evaluated tests ranged from 95%–100%.

Conclusions

ELISAs had greater overall sensitivity than RDTs. In conjunction with other parameters, the performance data can help determine which dengue diagnostics should be used during the first few days of illness, when the patients are most likely to present to a clinic seeking care.  相似文献   

20.

Background

MRI plays a major role in follow-up of patients with malignant bone tumors. However, after limb salvage surgery, orthopaedic tumor endoprostheses might cause significant metal-induced susceptibility artifacts.

Purposes

To evaluate the benefit of view-angle tilting (VAT) and slice-encoding metal artifact correction (SEMAC) for MRI of large-sized orthopaedic tumor endoprostheses in an experimental model and to demonstrate clinical benefits for assessment of periprosthetic soft tissue abnormalities.

Methods

In an experimental setting, tumor endoprostheses (n=4) were scanned at 1.5T with three versions of optimized high-bandwidth turbo-spin-echo pulse sequences: (i) standard, (ii) VAT and (iii) combined VAT and SEMAC (VAT&SEMAC). Pulse sequences included coronal short-tau-inversion-recovery (STIR), coronal T1-weighted (w), transverse T1-w and T2-w TSE sequences. For clinical evaluation, VAT&SEMAC was compared to conventional metal artifact-reducing MR sequences (conventional MR) in n=25 patients with metal implants and clinical suspicion of tumor recurrence or infection. Diameters of artifacts were measured quantitatively. Qualitative parameters were assessed on a five-point scale (1=best, 5=worst): “image distortion”, “artificial signal changes at the edges” and “diagnostic confidence”. Imaging findings were correlated with pathology. T-tests and Wilcoxon-signed rank tests were used for statistical analyses.

Results

The true size of the prostheses was overestimated on MRI (P<0.05). A significant reduction of artifacts was achieved by VAT (P<0.001) and VAT&SEMAC (P=0.003) compared to the standard group. Quantitative scores improved in the VAT and VAT&SEMAC group (P<0.05). On clinical MR images, artifact diameters were significantly reduced in the VAT&SEMAC-group as compared with the conventional-group (P<0.001). Distortion and artificial signal changes were reduced and diagnostic confidence improved (P<0.05). In two cases, tumor-recurrence, in ten cases infection and in thirteen cases other pathologies were diagnosed.

Conclusions

Significant reduction of metallic artifacts was achieved by VAT and SEMAC. Clinical results suggest, that these new techniques will be beneficial for detecting periprosthetic pathologies during postoperative follow-up.  相似文献   

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