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1.
Bronchial asthma in children may be difficult to diagnose. Education of the parents regarding allergic conditions, specifically bronchial asthma, is exceedingly important in order to assure satisfactory treatment and clinical results.Chest symptoms of unexplained origin in early life should immediately arouse suspicion of allergic disease. Other causes of asthmatic symptoms must be borne in mind and excluded before a positive diagnosis of bronchial asthma is established.Of the many factors to be considered in investigating a child with asthma, a comprehensive history is most essential. The climate to which the patient is exposed and the psychic influences must be taken into account. Physical examination, x-ray films and laboratory procedures should be carefully executed. Skin testing, especially with food allergens, should not be relied upon to give all the information in allergic disease. Some form of diet trial, such as elimination diets, should be used if sensitivity to food is suspected.  相似文献   

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Highland populations of several Drosophila species in Argentina were active early in the afternoon in the field as opposed to populations from a much warmer lowland site, where flies were mainly active in the early evening prior to sunset. For one of these species, Drosophila buzzatii, we tested for a genetic component of activity differences by carrying out crosses within and between populations and measuring oviposition activity of the progeny in the laboratory. We found that activity in the highland population exceeded that in the lowland one during the midafternoon, whereas activity in the lowland population exceeded that in the highland one prior to the beginning of the dark period. Oviposition activity for the period corresponding to the field observations was regressed on the proportion of the genome derived from the highland population. This variable significantly predicted oviposition activity between 1400 and 1600 and between 2000 and 2200 h. Activity of both reciprocal crosses was intermediate and not significantly different from each other, suggesting that nuclear genetic, rather than cytoplasmic factors contribute to differences in oviposition activity between the populations. Two morphological, one genetic, and one stress resistance trait were also scored to examine whether temperature differences between environments were associated with other differences between populations. Wing length of wild-caught and laboratory-reared flies from the highland population significantly exceeded that in the lowland. Thorax length of laboratory-reared flies from the highland population also significantly exceeded that from the lowland. Chromosomal inversion frequencies differed significantly between the two populations with a fivefold reduction in the frequency of arrangement 2st in the highland as compared to the lowland population. This arrangement is known for its negative dose effect on size, and thus, the highland population has experienced a genetic change, perhaps as a result of adaptation to the colder environment, where body size and the frequency of arrangement 2st have changed in concert. Finally, a heat knockdown test revealed that the lowland population was significantly more resistant to high temperature than the highland one. In conclusion, we suggest that temperature has been an important selective agent causing adaptive differentiation between these two populations. We also suggest that the activity rhythms of the two populations have diverged as a consequence of behavioral evolution, that is, through avoidance of stressful temperatures as a mean of thermal adaptation.  相似文献   

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Hurst SA 《Bioethics》2008,22(4):191-202
Despite broad agreement that the vulnerable have a claim to special protection, defining vulnerable persons or populations has proved more difficult than we would like. This is a theoretical as well as a practical problem, as it hinders both convincing justifications for this claim and the practical application of required protections. In this paper, I review consent-based, harm-based, and comprehensive definitions of vulnerability in healthcare and research with human subjects. Although current definitions are subject to critique, their underlying assumptions may be complementary. I propose that we should define vulnerability in research and healthcare as an identifiably increased likelihood of incurring additional or greater wrong. In order to identify the vulnerable, as well as the type of protection that they need, this definition requires that we start from the sorts of wrongs likely to occur and from identifiable increments in the likelihood, or to the likely degree, that these wrongs will occur. It is limited but appropriately so, as it only applies to special protection, not to any protection to which we have a valid claim. Using this definition would clarify that the normative force of claims for special protection does not rest with vulnerability itself, but with pre-existing claims when these are more likely to be denied. Such a clarification could help those who carry responsibility for the protection of vulnerable populations, such as Institutional Review Boards, to define the sort of protection required in a more targeted and effective manner.  相似文献   

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Brockman, II. E., and F. J. de Serres. (Oak Ridge Natl. Lab., Oak Ridge, Tenn.) “Sorbose toxicity” in Neurospora . Amer. Jour. Bot. 50(7): 709–714. Illus. 1963.—The effect of “sorbose toxicity” on Neurospora conidia or ascospores was compared in sorbose-fructose-glucose (S-F-G) and sorbose-sucrose (S-S) media. Many frequently encountered and difficultly controlled experimental variables may strongly affect viability in S-S media but are essentially without effect in S-F-G media. The viabilities of different mutant strains are affected to varying extents by autoclave exposure time of the S-S media but not of the S-F-G media. Ascospores are more sensitive than conidia to “sorbose kill” in S-S media. An over plating method described by New meyer (1954) for increasing ascospore “viability” is without effect when sucrose is replaced with fructose and glucose. In all experiments in which sorbose was added to induce colonial growth, “sorbose toxicity” or “sorbose kill” was eliminated or minimized by replacing sucrose with a mixture of fructose and glucose as the carbon source for Neurospora media.  相似文献   

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IntroductionThestudyofthemechanismofperistalticinbothmechanialandphysiologicalsituations,hasrecentlybecometheobjectofscientificresearch.SincethefirstinvestigationofLatham[1],severaltheoreticalandexperimentalattemptshavebeenmadetounderstandperistalticactionindifferentsituations.AreviewofmuchoftheearlyliteratureispresentedinanarticlebyJaffrinandShapiro[2].Asummaryofmostoftheexperimentalandtheoreticalinvestigationsreported,withdetailsofthegeometry,fluid,Reynoldsnumber,wavelengthparameter,waveam…  相似文献   

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The lymphoblastomas occurring in childhood are divided for purposes of discussion into lymphocytoma cutis, mycosis fungoides, lymphosarcoma, Hodgkin''s disease, and leukemia. The cutaneous lesions may be either specific (as a result of the infiltration of the skin with specific cells of the conditions) or toxic (non-specific). With the possible exception of mycosis fungoides, the cutaneous manifestations are not diagnostic. The final diagnosis depends upon microscopic examination of the specific tissue involved and the coordination of the clinical and microscopic findings.  相似文献   

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正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases  相似文献   

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Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.  相似文献   

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The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.  相似文献   

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Highlights
1. The N-terminal tail of histone H3 is specifically cleaved during EV71 infection.
2. Viral protease 3C is identified as a protease responsible for proteolytically processing the N-terminal H3 tail.
3. Our finding reveals a new epigenetic regulatory mechanism for Enterovirus 71 in virus-host interactions.  相似文献   

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Rasmussen’s encephalitis (RE) is a rare pediatric neurological disorder, and the exact etiology is not clear. Viral infection may be involved in the pathogenesis of RE, but conflicting results have reported. In this study, we evaluated the expression of both Epstein-Barr virus (EBV) and human herpes virus (HHV) 6 antigens in brain sections from 30 patients with RE and 16 control individuals by immunohistochemistry. In the RE group, EBV and HHV6 antigens were detected in 56.7% (17/30) and 50% (15/30) of individuals, respectively. In contrast, no detectable EBV and HHV6 antigen expression was found in brain tissues of the control group. The co-expression of EBV and HHV6 was detected in 20.0% (6/30) of individuals. In particular, a 4-year-old boy had a typical clinical course, including a medical history of viral encephalitis, intractable epilepsy, and hemispheric atrophy. The co-expression of EBV and HHV6 was detected in neurons and astrocytes in the brain tissue, accompanied by a high frequency of CD8+ T cells. Our results suggest that EBV and HHV6 infection and the activation of CD8+ T cells are involved in the pathogenesis of RE.  相似文献   

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Shen  Jia-Yuan  Li  Man  Xie  Lyu  Mao  Jia-Rong  Zhou  Hong-Ning  Wang  Pei-Gang  Jiang  Jin-Yong  An  Jing 《中国病毒学》2021,36(1):145-148
正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016).  相似文献   

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In conclusion, the novel visual RT-LAMP assay is a simple, rapid, and sensitive approach for detection of SARS-CoV-2, and it is ready for application in primary care and community hospitals or health care centers, and even patients' own houses in response to the current SARS-CoV-2 epidemic because the assay does not require sophisticated equipment and skilled personnel. Furthermore, it is also ready to be used in fields for screening samples from wild animals and environments to facilitate the identification of potential intermediate hosts that mediate the cross-species transmission of SARS-CoV-2 from bats to humans.  相似文献   

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