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1.
胃癌是因外邪侵袭、情志内伤、饮食失调等,致气机升降失调,气血津液运化失常,气滞、血瘀、痰浊及癌毒内生,日久积聚于胃脘而成。脾胃为气机升降之枢纽,脾不升清,胃不降浊,则精微不能濡养,浊液不能排出,影响体内正常气机升降。肝主疏泄,调节全身气机的条达,肝之疏泄功能失常,气机升降失调,则影响气血运行。气机升降关系在胃癌形成中起关键作用,气机升降失调,气血津液不能正常输布运行,则气凝血滞,痰浊内停,甚则癌毒内生,发为癌瘤。故在临床治疗中注重恢复脾胃的升降功能,辛开苦降,调畅气机,恢复脾胃的正常升降功能,为胃癌的治疗提供临床指导。 相似文献
2.
医学教育改革更多的是热衷于授课形式和方法的改革,而忽视了真正能够渗透到教学各方面的教学理念的改革。结合对生理学教学目标的反思和“岗位胜任力”培养的需求,将生理学教学的核心理念总结为四个方面:“三观”要正,帮助学生树立平衡观、辩证观和整体观;“三基”要牢,培养学生掌握基本的知识架构体系、基本的知识获取能力、基本的操作技能;重视学以致用和强化人文素养。上述核心理念在教学实践中得到学生的广泛认可,临床医学专业学生对核心理念的评价明显高于护理专业。下一步教学改革的方向是在教学理念的指导下如何细化授课内容,以适应专业设置越来越细化的现状。 相似文献
3.
Early life adversity impacts on a range of emotional, cognitive, and psychological processes. A recent theoretical model suggests that at least some of these effects are due to accelerated maturation of specific physiological systems and/or neural circuits. For example, maternal separation (MS), a model of early life adversity in rodents, accelerates maturation of memory systems, and here we examined its impact on maturation of perineuronal nets (PNNs) and parvalbumin (PV)-containing inhibitory interneurons. PNNs are specialized extracellular matrix structures suggested to be involved in stabilizing long-term memories and in the closure of a sensitive period in memory development. PV-containing inhibitory interneurons are the type of cell that PNNs preferentially surround, and are also thought to be involved in memory. In Experiment 1, with male rats, there was an increase in PNNs in both the amygdala and prefrontal cortex with age from infancy to juvenility. Contrary to prediction, MS had no impact on either PNN or PV expression. The same pattern was observed in female rats in Experiment 2. Taken together, these data show that the early maturation of memory in MS infants is not due to an accelerated maturation of PNNs or PV-containing cells in either the amygdala or prefrontal cortex. 相似文献
4.
《Journal of the American College of Radiology》2021,18(4):580-589
PurposeTo assess recent trends and characteristics in radiologist-practice separation across the United States.MethodsUsing the Medicare Physician Compare and Medicare Physician and Other Supplier Public Use File data sets, we linked all radiologists to associated group practices annually between 2014 and 2018 and assessed radiologist-practice separation over a variety of physician and group characteristics. Multivariate logistic regression modeling was used to estimate the likelihood of radiologist-practice separation.ResultsOf 25,228 unique radiologists associated with 4,381 unique group practices, 41.1% separated from at least one group practice between 2014 and 2018, and annual separation rates increased 38.4% over time (13.8% from 2014 to 2015 to 19.2% from 2017 to 2018). Radiologist-practice separation rates ranged from 57.4% in Utah to 26.3% in Virginia. Separation rates were 42.8% for general radiologists versus 38.2% for subspecialty radiologists. Among subspecialists, separation rates ranged from 43.0% for breast imagers to 33.5% for cardiothoracic radiologists. Early career status (odds ratio [OR] = 1.286) and late (OR = 1.554) career status were both independent positive predictors of radiologist-practice separation (both P < .001). Larger practice size (OR = 0.795), radiology-only (versus multispecialty) group (OR = 0.468), academic (versus nonacademic) practice (OR = 0.709), and abdominal (OR = 0.820), musculoskeletal (OR = 0.659), and neuroradiology (OR = 0.895) subspecialization were independent negative predictors (all P < .05).ConclusionsWith over 40% of radiologists separating from at least one practice in recent years, the US radiologist workforce is highly and increasingly mobile. Because reasons for separation (eg, resignation, practice acquisition) cannot be assessed using administrative data, further attention is warranted given the manifold financial, operational, and patient care implications. 相似文献
5.
Liquid–liquid phase separation (LLPS) represents a major physiochemical principle to organize intracellular membrane-less structures. Studies with non-segmented negative-sense (NNS) RNA viruses have uncovered a key role of LLPS in the formation of viral inclusion bodies (IBs), sites of viral protein concentration in the cytoplasm of infected cells. These studies further reveal the structural and functional complexity of viral IB factories and provide a foundation for their future research. Herein, we review the literature leading to the discovery of LLPS-driven formation of IBs in NNS RNA virus-infected cells and the identification of viral scaffold components involved, and then outline important questions and challenges for IB assembly and disassembly. We discuss the functional implications of LLPS in the life cycle of NNS RNA viruses and host responses to infection. Finally, we speculate on the potential mechanisms underlying IB maturation, a phenomenon relevant to many human diseases. 相似文献
6.
Episodic memory is defined as the ability to recall events in a spatiotemporal context. Formation of such memories is critically dependent on the hippocampal formation and its inputs from the entorhinal cortex. To be able to support the formation of episodic memories, entorhinal cortex and hippocampal formation should contain a neuronal code that follows several requirements. First, the code should include information about position of the agent (“where”), sequence of events (“when”), and the content of the experience itself (“what”). Second, the code should arise instantly thereby being able to support memory formation of one‐shot experiences. For successful encoding and to avoid interference between memories during recall, variations in location, time, or in content of experience should result in unique ensemble activity. Finally, the code should capture several different resolutions of experience so that the necessary details relevant for future memory‐based predictions will be stored. We review how neuronal codes in entorhinal cortex and hippocampus follow these requirements and argue that during formation of episodic memories entorhinal cortex provides hippocampus with instant information about ongoing experience. Such information originates from (a) spatially modulated neurons in medial entorhinal cortex, including grid cells, which provide a stable and universal positional metric of the environment; (b) a continuously varying signal in lateral entorhinal cortex providing a code for the temporal progression of events; and (c) entorhinal neurons coding the content of experiences exemplified by object‐coding and odor‐selective neurons. During formation of episodic memories, information from these systems are thought to be encoded as unique sequential ensemble activity in hippocampus, thereby encoding associations between the content of an event and its spatial and temporal contexts. Upon exposure to parts of the encoded stimuli, activity in these ensembles can be reinstated, leading to reactivation of the encoded activity pattern and memory recollection. 相似文献
7.
Sean Hutchinson Brendan Chapman Gavin Turbett 《The Australian journal of forensic sciences》2019,51(4):S95-S98
ABSTRACTIn many sexual assault cases, the most common evidence gathered comes in the form of intimate swabs. These swabs contain cells from both the female and male. In these cases the most common cell present is epithelial cells from the female with relatively few spermatozoa from the male. To produce an STR DNA profile suitable for an investigation, separation of the cell types is required to prevent a mixed profile that may complicate interpretation. While there are methods that can achieve this separation, they are labour intensive and have no guarantee of complete separation of the spermatozoa. Immunomagnetic bead separation techniques are being adapted from other scientific fields to be used in forensic biology to separate spermatozoa from mixed substrates. This study tested the binding of a Hyaluronidase PH-20 (SPAM1) antibody to spermatozoa in mixed cell samples that have been dried and stored for a short period of time. Fluorescently tagged antibodies were incubated with cellular mixtures and visualized using fluorescent microscopy. Successful binding of the antibodies to spermatozoa was observed in all samples. The SPAM1 antibody appears to be suitable for selection of spermatozoa and creates opportunities for linking with magnetic beads facilitate cell separation and DNA profiling. 相似文献
8.
Nicole Di Lascio Claudia Kusmic Chiara Rossi Anna Solini Francesco Faita 《Ultrasound in medicine & biology》2019,45(4):980-988
Information on the common carotid artery and cerebral microcirculation can be obtained by micro-ultrasound (µUS). The aim of the study described here was to investigate high-fat diet-induced alterations in vascular parameters in ApoE–/– mice. Twenty-two ApoE–/– male mice were examined by µUS and divided into the standard diet (ApoE–/–SD) and high-fat diet (ApoE–/–HF) groups. The µUS examination was repeated after 4 mo (T1). Carotid stiffness, reflection magnitude and reflection index were measured; the amplitudes of the first (W1) and second (W2) local maxima, the local minimum (Wb) and the reflection index (RIWIA?=?Wb/W1) were assessed with wave intensity analysis. At T1, ApoE–/–HF mice had increased carotid stiffness (1.48 [0.36] vs. 1.88 [0.51]) and reflection magnitude (0.89 [0.07] vs. 0.94 [0.07]) values. Longitudinal comparisons highlighted increases in carotid stiffness for ApoE–/–HF mice (from 1.37 [0.25] to 1.88 [0.51] m/s) but not for ApoE–/–SD mice (from 1.40 [0.62] to 1.48 [0.36] m/s). ApoE–/–HF mice exhibited carotid artery stiffening and increased wave reflections. 相似文献
9.
反流性食管炎(RE)是由于胃或十二指肠的内容物反流入食管,而引起食管组织黏膜炎症、糜烂和纤维化等病变。属于胃食管反流病(GERD)的范畴,临床上以反酸、烧心、灼热、疼痛、嗳气等为主要表现,常见的并发症为食管狭窄、出血、Barrett食管及食管腺癌等。中医学中没有反流性食管炎的病名,但根据其临床表现,可以归属于“吞酸”、“吐酸”、“嘈杂”、“胃脘痛”等范围。中医对反流性食管炎的认识逐渐完善,治疗上以“和法”为主,并取得了良好的疗效。但因在中医病名、辨证和治疗上缺乏统一标准,有待临床进一步研究。本文通过查阅相关文献,概括出反流性食管炎的中医病因病机、辨证分型、治则治法及常用方药,探讨反流性食管炎的中医学研究进展。 相似文献
10.
Adverse early life experiences, such as maternal separation, are associated with an increased risk for several mental health problems. Symptoms induced by maternal separation that mirror clinically relevant aspects of mental problems, such as cognitive inflexibility, open the possibility of testing putative therapeutics prior to clinical development. Although several animal (e.g., rodent) studies have evaluated the effects of early maternal separation on cognitive flexibility, no consistent conclusions have been drawn. To clarify this issue, in this study, a meta-analysis method was used to systematically explore the relationship between early maternal separation and cognitive flexibility in rodent offspring. Results indicate that early maternal separation could significantly impair cognitive flexibility in rodent offspring. Moderator analyses further showed that the relationship between early maternal separation and cognitive flexibility was not consistent in any case, but was moderated by variations in the experimental procedures, such as the deprivation levels, task characteristics, and rodent strains. These clarify the inconsistent effects of maternal separation on cognitive flexibility in rodents and help us better understand the association between early life adversity and cognitive development. 相似文献