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1.
Modification of rats behaviour in an "hopen field" test was investigated, induced by an acoustic stimulus, previously subjected to conditioning in a shuttle chamber in experiments with possibility and impossibility of avoidance from electrical shock. It has been established that presentation of a stimulus having the meaning of a danger signal, in a new situation, significantly suppresses investigating behaviour of rats, whereas the stimulus which had not been subjected to conditioning exerts no marked effect on behaviour. The greatest suppression was observed in rats with "learned helplessness". This fact suggests that the degree of suppression of the behaviour in an open field in response to a danger signal, depends on the animal's previous experience in reacting to this signal.  相似文献   

2.
The case outlined below is the basis for the In That Case section of the “Ethics and Epistemology of Big Data” symposium. Jordan receives reports from two separate personal genomic tests that provide intriguing data about ancestry and worrying but ambiguous data about the potential risk of developing Alzheimer’s disease. What began as a personal curiosity about genetic inheritance turns into an alarming situation of medical uncertainty. Questions about Jordan’s family tree are overshadowed by even more questions about Alzheimer’s disease and healthy ageing. As a parent, Jordan is unsure whether to share these results and what it would mean for their children to learn about their genetic inheritance and potential future health. Furthermore, Jordan is unsure how to make sense of these reports in light of current knowledge of the risk factors for Alzheimer’s disease and in the absence of effective treatments or robust preventative guidelines.  相似文献   

3.
Little is known about the dynamic characteristics of stress system activity during "life as it is lived". Using as representative a study design as possible, this investigation sought to gain insights into this area. A healthy 25-year-old woman collected her entire urine over a period of 63 days in 12-h intervals (126 measurements) to determine cortisol and neopterin (immune activation marker) levels. In addition, she filled out questionnaires on emotional state and daily routine in 12-h intervals, and was interviewed weekly to identify emotionally negative and positive everyday incidents. Adjusted cross-correlational analyses revealed that stressful incidents were associated with cyclic response patterns in both urinary cortisol and urinary neopterin concentrations. Urinary cortisol levels first decreased 12-24 h after stressful incidents occurred (lag 1: -.178; p = 0.048) and then increased a total of 72-84 h later (lag 6: +.224; p = 0.013). Urinary neopterin levels first increased 0-12 h before the occurrence of stressful incidents (-lag 1: +.185; p = 0.040) and then decreased a total of 48-60 h following such stressors (lag 4: -.181; p = 0.044). Decreases in urinary neopterin levels were also found 24-36 and 48-60 h after increases in pensiveness (lag 2: -.215; p = 0.017) and depressiveness (lag 4: -.221; p = 0.014), respectively. Findings on emotionally positive incidents sharply contrasted with those dealing with negative experiences. Positive incidents were followed first by urinary cortisol concentration increases within 12 h (lag 0: +.290; p = 0.001) and then by decreases after a total of 60-72 h (lag 5: -.186; p = 0.039). Urinary neopterin levels first decreased 12-24 h before positive incidents occurred (-lag 2: -.233; p = 0.010) and then increased a total of 12-24 h following these incidents (lag 1: +.222; p = 0.014). As with previous investigations on patients with systemic lupus erythematosus (SLE), this study showed that stress system response can be considerably longer and more complex and differentiated than findings from conventional group studies have suggested. Further integrative single-case studies will need to be conducted in order to draw firm conclusions about stress system dynamics under real-life conditions.  相似文献   

4.
The paper is devoted to analysis of the results of CT in 1000 patients examined in the Multibranch Research and Technology Complex "Eye Microsurgery". The specific feature of CT in this institution is that 52% of all investigations of ophthalmological patients fall to the share of eyeball abnormality and 40%--to a study of the other parts of the organ of vision. CT indications are extended for low tension glaucoma, complicated high myopia, and for monitoring the position of microsurgical implants. The use of CT in such a highly specialized medical institution as the MRTC "Eye Microsurgery" is considered indispensable.  相似文献   

5.
Maya mobile medical providers in highland Guatemala and the goods and services that they offer from "soapboxes" on street corners, local markets, and on buses exemplify an important yet underinvestigated domain of localized health care, one that I refer to as the "other" public health. This medical and linguistic examination of traveling medical salespeople calls for a reconsideration (on a global scale) of what has come to be understood as "public health," arguing that "othered," local forms of public health that are often overlooked by anthropologists as "nontraditional" and delegitimized by bio-medicine as nonscientific merit serious consideration and investigation. This ethnography of marginalized forms of public health offers global insights into emerging heterodoxical forms of public health care that contest bio-medical authority and challenge our preexisting definitions of what counts as "access," wellness seeking, and even health care itself.  相似文献   

6.
The alarming levels of spread and severity of COVID-19 have dominated global attention. In this time of crisis, there is an urgent need for studies identifying the linkages between the pandemic and social welfare. To help policymakers respond to the situation better, we investigate how the severity of the COVID-19 pandemic can condition people's psychological well-being. Employing the latest weekly panel data within an individual fixed effects framework, we uncover the damaging consequences of the COVID-19 severity, as measured by mortality rate, on the incidences of daily anxiety, worry, displeasure, and depression in the United States. Our work underlines the importance of public spending on mental health, both during and after the pandemic.  相似文献   

7.
A method has been elaborated of training the human subjects to avoid electric shocks by overcoming the "fear" caused by a warning signal. A previously elaborated differentiated conditioned skin-galvanic response (SGR) to a sound stimulus served as a criterion of the emotional reaction. The SGR was projected on an oscilloscope screen. The electric shock was automatically delivered at the moment when the amplitude of the conditioned SGR exceeded the level marked on the screen. The subject was instructed, by overcoming the "fear", to retain the SGR amplitude below the level. If the subject succeeded in overcoming the conditioned SGR to the signal, the shock was not delivered. Since, the suppression of the conditioned SGR served as a "instrument" of avoidance and became consolidated as a habit based on a positive reinforcement. The subjects developed a stable attraction to repetition of training sessions in which they learned to suppress the "anxiety" caused by a signal of "threat".  相似文献   

8.
详细比较藏药"藏茵陈"基原植物川西獐牙菜及其混淆品(代用品)抱茎獐牙菜、紫红獐牙菜、四数獐牙菜、红直獐牙菜、大籽獐牙菜、狭叶獐牙菜和椭圆叶花锚的外部形态特征及化学成分,澄清了这一类群在分类上的混乱,发现川西獐牙菜与紫红獐牙菜在习性,花部特征,种子形态和化学成分组成等方面相似性最高,印证了核基因ITS序列的结果。同时分析"藏茵陈"混淆的原因是多种来源和形态相似性造成的,讨论了"藏茵陈"鉴定的方法。通过对獐牙菜属系统关系的分析,提出紫红獐牙菜作为川西獐牙菜替代品的理论依据。  相似文献   

9.
The vanishing mother: Cesarean section and "evidence-based obstetrics"   总被引:1,自引:0,他引:1  
The philosophy of "evidence-based medicine"--basing medical decisions on evidence from randomized controlled trials and other forms of aggregate data rather than on clinical experience or expert opinion--has swept U.S. medical practice in recent years. Obstetricians justify recent increases in the use of cesarean section, and dramatic decreases in vaginal birth following previous cesarean, as evidence-based obstetrical practice. Analysis of pivotal "evidence" supporting cesarean demonstrates that the data are a product of its social milieu: The mother's body disappears from analytical view; images of fetal safety are marketing tools; technology magically wards off the unpredictability and danger of birth. These changes in practice have profound implications for maternal and child health. A feminist project within obstetrics is both feasible and urgently needed as one locus of resistance.  相似文献   

10.
11.
We previously discovered that a 4-wk course of indomethacin delivered to rats with acetic acid ulcers resulted in production of "unhealed gastric ulcers" that persisted for up to 12 wks after treatment cessation. The present study examined the mechanism underlying such "unhealed gastric ulcers" with biochemical and histological procedures. "Unhealed gastric ulcers" were induced with a 4-wk indomethacin treatment (1 mg/kg, twice daily) in rats with acetic acid ulcers. Two and 4 wks after treatment cessation, ulcer size was significantly larger in rats receiving indomethacin compared with control animals. Ulcerated tissue prostaglandin E2 levels were significantly lower during indomethacin treatment, but the levels tended to increase after treatment cessation compared with levels measure in the group receiving vehicle. Myeloperoxidase activity levels were significantly higher during indomethacin treatment; such levels persisted after treatment cessation. Histologically, greater degrees of fibrosis and neutrophil accumulation, as well as a lesser degree of angiogenesis were observed in the "unhealed gastric ulcers" compared to ulcers that healed in a normal fashion. It was concluded that severe fibrosis, persistent neutrophil infiltration, and poor angiogenesis in the ulcer base might represent factors involved in the mechanism underlying production of "unhealed gastric ulcers".  相似文献   

12.
Formulations from the traditional Indian medicine, Ayurveda, have long been considered to have potent life-style-enhancing effects, possibly by their effect(s) on key life-history attributes. Although several studies have reported beneficial effects of these formulations on different components of life history, few have investigated their concurrent influence on various life-history traits. Here, we report the results of an investigation showing the effect of two well-known Ayurvedic formulations, Guduchi and Madhuyashti, on fecundity and longevity of Drosophila melanogaster. Flies were either grown (i.e., larval exposure) and/or maintained (i.e., adult exposure) on standard food supplemented with 0.5% Guduchi or 0.5% Madhuyashti. It was observed that the longevity of adult flies of both sexes was not affected on feeding Guduchi food, but fecundity of the females was greatly enhanced. Fecundity was also found to be affected by the adult food and whether their mates were grown on Guduchi or normal food. Madhuyashti, on the other hand, significantly reduced mean longevity and had a stimulatory effect on female fecundity. This fecundity enhancing effect however seemed to be mediated through its effect on the males. Interestingly, much of these effects interacted with age in a complex way, making it difficult to generalize the overall effect of these formulations on the reproductive output of the flies. Our study underlines the importance of evaluating the interacting effects of these (and similar) formulations on a range of life-history traits in a holistic way to understand their utility better.  相似文献   

13.
Benjamin Franklin had at least two accidents that resulted in electricity passing through his brain. In addition, he witnessed a patient's similar accident and performed an experiment that showed how humans could endure shocks to the head without serious ill effects, other than amnesia. Jan Ingenhousz, Franklin's Dutch-born medical correspondent better known for his discovery of photosynthesis, also had a serious accident that sent electricity though his head and, in a letter to Franklin, he described how he felt unusually elated the next day. During the 1780s, Franklin and Ingenhousz encouraged leading French and English electrical "operators" to try shocking the heads of melancholic and other deranged patients in their wards. Although they did not state that they were responding to Ingenhousz's and Franklin's suggestions, Birch, Aldini, and Gale soon did precisely what Ingenhousz and Franklin had suggested. These practitioners did not appear to induce convulsions in their mentally ill patients, but they still reported notable successes.  相似文献   

14.
Background: In 1986, two Canadian geneticists had demonstrated that Joseph Merrick, better known as the Elephant Man, suffered from the Proteus syndrome and not from neurofibromatosis type 1 (NF1), as was alleged by dermatologist Parkes in 1909. Despite this and although the two diseases differ at several levels: prevalence, diagnostic criteria, clinical manifestations and transmission, the confusion between NF1 and the "elephant man's" disease continues in medical and social representations by current linguistic usage, and in some media reports. With this article, we want to 1) document the persistence and extent of this fallacy, 2) identify certain critical factors that contribute to its persistence, and 3) evaluate its impact on the health and well being of patients with NF1 and their family members.Methodology: Participant observation in the course of an ethnographic study on intergenerational dialogue between individuals with neurofibromatosis and their parents - Analysis of the scientific literature and of pinpoint articles in the print and online news media.Findings: Our findings show that because physicians have little knowledge about NF1, several print and online news media and a lot of physicians continue to make the confusion between NF1 and the disease the "elephant man". This misconception contributes to misinformation about the disease, feeding prejudices against affected patients, exacerbating the negative impacts of the disease on their quality of life, their cognitive development, their reproductive choices, as well as depriving them of proper care and appropriate genetic counseling.Conclusion: If family physicians and pediatricians were properly informed about the disease, they could refer their patients with NF1 to NF clinics and to specialists. Thus, patients and their family members would benefit from better-tailored clinical management of their cases, perhaps even optimal management. [corrected]  相似文献   

15.
HELGA KUHSE 《Bioethics》1995,9(3):207-219
According to a contemporary school of thought there is a specific female approach to ethics which is based not on abstract "male" ethical principles or rules, but on "care". Nurses have taken a keen interest in these female approaches to ethics. Drawing on the views expounded by Carol Gilligan and Nel Noddings, nurses claim that a female "ethics of care" better captures their moral experiences than a traditional male "ethics of justice". This paper argues that "care" is best understood in a dispositional sense, that is, as sensitivity and responsiveness to the particularities of a situation and the needs of "concrete" others. While "care", in this sense, is necessary for ethics, it is not sufficient. Ethics needs "justice" as well as "care". If women and nurses excessively devalue principles and norms, they will be left without the theoretical tools to condemn some actions or practices, and to defend others. They will, like generations of nurses before them, be condemned to silence.  相似文献   

16.
Kuhse H 《Bioethics》1995,9(3-4):207-219
According to a contemporary school of thought there is a specific female approach to ethics which is based not on abstract "male" ethical principles or rules, but on "care". Nurses have taken a keen interest in these female approaches to ethics. Drawing on the views expounded by Carol Gilligan and Nel Noddings, nurses claim that a female "ethics of care" better captures their moral experiences than a traditional male "ethics of justice". This paper argues that "care" is best understood in a dispositional sense, that is, as sensitivity and responsiveness to the particularities of a situation and the needs of "concrete" others. While "care", in this sense, is necessary for ethics, it is not sufficient. Ethics needs "justice" as well as "care". If women and nurses excessively devalue principles and norms, they will be left without the theoretical tools to condemn some actions or practices, and to defend others. They will, like generations of nurses before them, be condemned to silence.  相似文献   

17.
In the Sunni Muslim world, religious mandates prohibit both adoption and gamete donation as solutions to infertility, including in the aftermath of in vitro fertilization (IVF) failures. However, both of these options are now available in two Middle Eastern countries with significant Shi'ite Muslim populations (Iran and Lebanon). On the basis of fieldwork in multisectarian Lebanon, I examine in this article attitudes toward both adoption and gamete donation among childless Muslim men who are undertaking IVF with their wives. No matter the religious sect, most Muslim men in Lebanon continue to resist both adoption and gamete donation, arguing that such a child "won't be my son". However, against all odds, some Muslim men are considering and undertaking these alternatives to family formation as ways to preserve their loving marriages, satisfy their fatherhood desires, and challenge religious dictates, which they view as out of step with new developments in science and technology. Thus, in this article I examine the complicated intersections of religion, technology, marriage, and parenthood in a part of the world that is both poorly understood and negatively stereotyped, particularly in the aftermath of September 11, 2001.  相似文献   

18.
Exposure to unpredictable and uncontrollable conditions causes animals to perceive stress and change their behavior. It is unclear how the perception of stress modifies the motor components of behavior and which molecular pathways affect the behavioral change. In order to understand how stress affects motor function, we developed an experimental platform that quantifies walking motions in Drosophila. We found that stress induction using electrical shock results in backwards motions of the forelegs at the end of walking strides. These leg retrogressions persisted during repeated stimulation, although they habituated substantially. The motions also continued for several strides after the end of the shock, indicating that stress induces a behavioral aftereffect. Such aftereffect could also be induced by restricting the motion of the flies via wing suspension. Further, the long-term effects could be amplified by combining either immobilization or electric shock with additional stressors. Thus, retrogression is a lingering form of response to a broad range of stressful conditions, which cause the fly to search for a foothold when it faces extreme and unexpected challenges. Mutants in the cAMP signaling pathway enhanced the stress response, indicating that this pathway regulates the behavioral response to stress. Our findings identify the effect of stress on a specific motor component of behavior and define the role of cAMP signaling in this stress response.  相似文献   

19.
In 1925, the German biologist and philosopher Hans Driesch published a booklet entitled The Crisis in Psychology. It was originally published in English and was based on lectures given at various universities in China, Japan and the USA. The "crisis" in psychology of that time, in Driesch's opinion, lies in the necessity to decide about "the road which psychology is to follow in the future". This necessity refers to five "critical points", namely (1) to develop the theory of psychic elements to a theory of meaning by phenomenological analysis, (2) the overcoming of association theory, (3) to acknowledge that the unconscious is a fact and a "normal" aspect of mental life, (4) to reject "psychomechanical parallelism" or any other epiphenomenalistic solution of the mind-body problem, and (5) the extension of psychical research to new facts as described by parapsychology, for instance. Driesch saw close parallels between the development of modern psychology and that of biology, namely in a theoretical shift from "sum-concepts" like association and mechanics, to "totality-concepts" like soul and entelechy. The German translation of 1926 was entitled Grundprobleme der Psychologie (Fundamental Problems of Psychology) while "the crisis in psychology" forms just the subtitle of this book. This underlines that Driesch's argumentation--in contrast to that of Buehler--dealt with ontological questions rather than with paradigms.  相似文献   

20.
We all possess T cells with autoaggressive potential. Knowledge of their regulation is crucial for elucidating pathogenetic pathways and designing effective treatments for autoimmune diseases. A novel mechanism of T-cell silencing--in an autoimmune model--has recently been identified and is termed "epitope theft". The "thieves" are naive CD8+ T cells, which apparently "steal" MHC-class-I-antigen complexes from antigen-presenting cells (APCs). The deprived APCs can no longer activate other potentially pathogenic naive CD8+ T cells that are specific for the same epitope. This phenomenon is a previously unrecognized antigen-specific mode of protection against autoimmunity.  相似文献   

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