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Primary apocrine carcinoma of the sweat gland is a neoplasm with a very low incidence that may represent a clinical and histological diagnostic challenge, as well as for adequate local, adjuvant, and advanced disease management. The average age of patients is around 67 years with no gender preference. This cancer develops primarily at the axillary and scalp levels and is clinically characterized by slow growth, but can progress aggressively with local, nodal, and metastatic involvement (primarily lung, liver, and bone). The recommended management, once the histology is established, consists of a wide local resection with a clear margin of 1 to 2 cm and regional lymphadenectomy if clinically positive nodes are detected. The adjuvant treatment (radiotherapy or chemotherapy) and for the advanced disease is not established.We report here the cases of two female patients initially diagnosed with breast cancer who were finally diagnosed with apocrine carcinoma of the sweat gland.  相似文献   

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The tropical verrucous syndrome includes infectious, chronic, and granulomatous skin conditions appearing with plaques, nodules, or ulcers with a warty surface which gives name to the syndrome. It includes forms of chromoblastomycosis, sporotrichosis, paracoccidioidomycosis, lobomycosis, leishmaniasis, and tuberculosis verrucosa cutis with ample distribution in tropical and subtropical areas. The diagnoses may be difficult and confused among them, especially between sporotrichosis and leishmaniasis.Clinical, epidemiologic, intradermal reactions, direct smears, skin biopsies, cultures, immunofluorescence, and PCR are used to differentiate them, although several of these methods are not commonly used.We present an 18-year-old man with extensive verrucous plaques in one knee interpreted by clinic, epidemiology, and biopsy as verrucous cutaneous leishmaniasis. He was treated with Glucantime® for 20 days without improvement. A new biopsy was made that was also interpreted as cutaneous leishmaniasis. The revision of both biopsies showed inflammation with abscessed granulomas and asteroid sporotrichotic bodies at the center of the granulomas that led to the diagnosis of sporotrichosis later confirmed by the fungus culture. The patient responded to the treatment with itraconazole. As clinical and epidemiological findings of leishmaniasis and sporotrichosis can be similar, skin biopsy and other paraclinical studies are necessary to establish a proper diagnosis. The asteroid sporotrichotic body is pathognomonic of this mycosis. We review here the essential concepts of leishmaniasis and sporotrichosis and the criteria to differentiate them.  相似文献   

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The increasing problem of antibiotic resistance in bacteria requires the development of new antimicrobial candidates. There are several well-known substances with commercial use, but their molecular mode of action is not fully understood. In this work, we focus on two commonly used antimicrobial agents from the detergent family—octenidine dichloride (OCT) and chlorhexidine digluconate (CHX). Both of them are reported to be agents selectively attacking the cell membrane through interaction inducing membrane disruption by emulsification. They are believed to present electrostatic selectivity toward charged lipids. In this study, we tested this hypothesis and revised previously proposed molecular mechanisms of action. Employing a variety of techniques such as molecular dynamics, ζ potential with dynamic light scattering, vesicle fluctuation spectroscopy, carboxyfluorescein leakage measurement, and fluorescence trimethylammonium-diphenylhexatriene- and diphenylhexatriene-based studies for determination of OCT and CHX membrane location, we performed experimental studies using two model membrane systems—zwitterionic PC and negatively charged PG (18:1/18:1):PC (16:0/18:1) 3:7, respectively. These studies were extended by molecular dynamics simulations performed on a three-component bacterial membrane model system to further test interactions with another negatively charged lipid, cardiolipin. In summary, our study demonstrated that detergent selectivity is far more complicated than supposed simple electrostatic interactions. Although OCT does disrupt the membrane, our results suggest that its primary selectivity was more linked to mechanical properties of the membrane. On the other hand, CHX did not disrupt membranes as a primary activity, nor did it show any sign of electrostatic selectivity toward negatively charged membranes at any stage of interactions, which suggests membrane disruption by influencing more discrete membrane properties.  相似文献   

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《当今生物学》2018,48(1):27-35
MHC‐Genes: Do they influence the choice of partners via olfactory signals? Behavioral experiments in mice and humans suggest that genes of the major histocompatibilty complex (MHC) may be important for the differentiation of self and non‐self during mate choice. While this correlation is well documented for certain mouse strains, it is controversial for humans. Signal transfer between potential partners is considered to occur via the production of MHC‐dependent olfactory cues by a sender and their recognition by olfaction in the recipient. It is shown that in mice and humans the overall bouquet of volatiles is not and the pattern of peptides in mice is only marginally influenced by the MHC genes. However, in mice, olfactory cues without MHC contribution appear to play a role in mate choice, in that the profile learned from the parents during rearing is compared with the distinct profile of a potential partner, which is in turn selected for mating. Such olfactory differentiation between close relatives and potential mates without MHC‐contribution may also operate unconsciously in humans.  相似文献   

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Although much research has been carried out on Australopithecus afarensis locomotion, no consensus has yet been reached. Our new critic study on femoral material brings to the fore a strictly bipedal behaviour within this taxon. Our results are based on the pertinence of human anatomical characteristics among A. afarensis and on the absence of characteristics revealing arboreal displacement. These results have emerged from our different observation and interpretation of some preceding authors concerning the anatomy of these fossil hominids. It is important to underline that apomorphic characteristics of this species are difficult to interpret. They must not however be used to support the idea of arboreal displacement simply based on the fact of a no totally human morphe. We believe that present day humans do not necessarily reflect the earliest strict bipedal anatomic model. An the other hand, it appears that the disagreement between the two locomotor hypothesis for A. afarensis that are bipedalism and arboreal displacement, facing the possibility of bipedalism associated with negligible arboreal displacement, results more from an evolutionary fact than from a real scientific conflict.  相似文献   

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Localized prostate cancer is characterized by a tumor confined to the prostate gland at clinical evaluation. Since the onset of PSA screening, the detection of localized prostate cancer has increased. Prognosis factors are clinical stadification, PSA value, PSA doubling time, tumor volume related to needle biopsy pathologic findings (Gleason score, percentage biopsies involved). Treatment depends on tumor prognosis, symptoms and performance status of the patient. Localized prostate cancer can be treated by surgery (radical prostatectomy, high intensity focused ultrasound) or radiotherapy (conformational radiation therapy, brachytherapy). Active follow-up can be proposed to very low risk patients.  相似文献   

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Specificity of the Attachment of Agrobacterium to Wound Cells of Kalanchoe? Tumor induction by A. tumefaciens on leaves of Kalanchoe is severely inhibited by cell wall preparations from young and mature tissucs of monocotyledons and dicoryledons and from tumor cells and also by filter paper homogenates and living or dead Pseudomonas cells. The inhibition a demonstrable if the cell wall preparations or Pseudomonas cells are inoculated into the plant wounds at the same time with A tumefaciens or before A. tumefaciens a. Postinoculation does affect tumor These results demonstrate site binding as an important step of tumor induction without any doubt but at the same time they question the specificity of this process.  相似文献   

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A lithic tool has appeared for the first time at Sima de los Huesos (Atapuerca, Spain). It is a finely flaked quartzite handaxe, which is associated with the hominid assemblage of a MNI of 27 Homo heidelbergensis, dated more than 350,000 years ago. The particular nature of the deposit involving its taphonomy, paleontology, and technology points to a symbolic meaning both of the tool and the human accumulation.  相似文献   

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《Médecine Nucléaire》2007,31(9):506-513
Internal targeted radiotherapy (ITR), which consists in irradiation of small disseminated tumour lesions using injected radiopharmaceuticals has been for a long time successfully used for differentiated thyroid carcinoma treatment, as an adjuvant treatment after surgery, but as an efficient treatment of metastatic disease (especially lung involvement) as well. New efficient radiopharmaceuticals for tumour targeting become available, making feasible such successful ITR treatment for other endocrine tumours (ET). Malignant phaeochromocytomas have firstly been treated with 131I-metaiodobenzyguanidine (MIBG) and more recently radiolabeled ligands of somatostatine receptors (SSR) which are overexpressed by most of ET have been proved to be an effective treatment of these tumours. Moreover, radiolabelled antibodies, which have been used successfully in malignant lymphoma treatment, could have an interest in ET, mainly medullary thyroid carcinoma. Using ITR for ET treatment suppose clinical indications are well defined, according to the new WHO classification of ET: only non-differentiated not eradicable and/or metastatic progressive tumours should be treated. Furthermore, efficiency of ITR is greater than could be thought as minor responses and even prolonged stabilizations are now considered as positive responses. Randomized studies are still necessary, however, in order to demonstrate, beyond its efficiency, a clinical impact of ITR on quality of life and survival, and to determine the right place of ITR in the global therapeutic management of ET.  相似文献   

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草食动物采食对草地植物多样性和生态系统功能的影响机制是放牧生态学研究的核心问题。该研究以内蒙古锡林郭勒盟苏尼特右旗荒漠草原的长期放牧控制实验为平台, 从既有草地植物多样性和动物偏食性两个层面系统地研究了荒漠草地植物多样性对草食动物采食的响应机制。结果显示: 1)荒漠草地植物对草食动物采食呈现4种响应模式: 放牧“隐没种”、放牧“敏感种”、放牧“无感种”、“绝对优势种”; 2)在群落尺度上, 物种多样性指数随放牧强度增加而减少, 与不放牧小区相比, 重度放牧(HG)与适度放牧(MG)小区植物多样性均下降, 且这一规律同样适用于功能群多样性, 灌木半灌木这一功能群内物种多样性对放牧干扰较敏感; 3)在草地既有植物的基础上, 以不放牧小区为参考系, 草食动物对植物功能群偏食性的排序为: 一二年生草本(AB) >多年生杂类草(PF) >灌木半灌木(SS) >多年生禾草(PG), 且偏食性物种主要分布于AB和PF中; 4)植物多样性与动物偏食性基本呈显著负相关关系(p < 0.05)。  相似文献   

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Inspired by Grant Evans’ work Tai‐ization: Ethnic Change in Northern Indo‐China, this article explores aspects of historical ethnic change in the Yunkai and Yunwu Mountain Ranges, a small upland region intersected by the boundary of Guangdong and Guangxi provinces in southern China over the period 600–1700 C.E. The discussion begins with some of the early linguistic evidence for populations of Tai speakers in the region and what is known of their political and cultural systems, then moves on to consider how Chinese military conquests of the eighth century coupled with the migration of Sinitic and Mien peoples from the eleventh century onwards altered the ethnic composition and political landscape of the region. This is followed by an examination of different exonyms used in Chinese texts for populations of southern China from the fifteenth century onwards and how these might have related to linguistic groupings and identities on the ground, demonstrating that historical usage of Chinese exonyms now connected with Tai or Mien speakers is not always a reliable indicator of a corresponding presence of historical Tai or Mien‐speaking populations. Further research drawing on a number of disciplines is required on a localised level in order to determine when Tai and Mien languages were abandoned in the region and how the inhabitants of the area shifted from the status of named Others to ordinary Chinese subjects.  相似文献   

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李孟悦  刘柳  刘艳  张晓曼 《植物学报》2021,56(6):732-739
以毛报春(Primula × pubescens)无菌腋芽为外植体, 分析不同浓度激素配比对愈伤组织诱导和分化以及不定芽增殖和生根的影响, 筛选出不同阶段的最适培养基, 优化毛报春的组织培养再生体系。结果表明, 毛报春腋芽愈伤组织诱导及分化的最适培养基为MS+0.2 mg∙L-1 NAA+1.0 mg∙L-1 6-BA, 诱导率达84%, 出芽率达67%; 不定芽增殖最适培养基为MS+0.5 mg∙L-1 NAA+0.2 mg∙L-1 6-BA, 增殖率可达67%, 苗绿且健壮; MS+0.2 mg∙L-1 NAA培养基最有利于组培苗的生根及伸长, 平均单株生根数为9条, 生根率高达70%。该研究建立了毛报春的组织培养再生体系, 可为报春属其它植物的遗传研究及种质创新提供参考。  相似文献   

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Centenarians surpass the current human life expectancy with about 20–25 years. However, whether centenarians represent healthy aging still remains an open question. Previous studies have been hampered by a number of methodological shortcomings such as a cross-sectional design and lack of an appropriate control group. In a longitudinal population-based cohort, it was examined whether the centenarian phenotype may be a useful model for healthy aging. The study was based on a complete follow up of 39 945 individuals alive in the Danish 1905 birth cohort on January 1, 1977 identified through the Danish Civil Registration System (DCRS). Data from the Danish Demographic Database and The Danish National Patient Register (in existence since 1977) were used. The 1905 cohort was followed up from 1977 through 2004 with respect to hospitalizations and number of hospital days. Survival status was available until December 2006. Danish centenarians from the 1905 cohort were hospitalized substantially less than their shorter-lived contemporaries at the same point in time during the years 1977 through 2004. For example, at age 71–74, the proportion of nonhospitalized centenarians was 80.5% compared with 68.4% among individuals who died in their early 80s. This trend was evident in both sexes. As a result of their lower hospitalization rates and length of stay in hospital compared with their contemporaries, who died at younger ages, Danish centenarians represent healthy agers. Centenarians constitute a useful study population in the search for fixed traits associated with exceptional longevity, such as genotype.  相似文献   

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《L'Anthropologie》2015,119(2):141-169
Across the Near-East and particularly in Syria, a number of archaeological sites have delivered new industries which can be linked to the intermediate Palaeolithic, more commonly qualified as “Transition industry” Due to the apparition of several facies with new technical orientations, the term of intermediate Palaeolithic seems most appropriate. The bladelets production is one of those innovations. Among the four facies identified in the Palmyra and the El Kowm basins (central Syria), facies 3 and 4 are the most frequent and the best documented in terms of chrono-stratigraphical sequence. Here we present the facies 3 discovered in stratigraphy on the site of Umm el Tlel. This facies has been dated and the industries have been submitted to a micro use-wear analysis. The levels III2a’ and II base’, selected for analysis and dated around 36,000 ± 2500 years (T.L.), are characterized by different modes of production and by various predetermined removals. Among these productions, the bladelets represent more than a third of the predetermined removals. These bladelets have various morphologies and dimensions and result from two modes of production. The first mode consists in alternating Levallois products and bladelets and the second mode utilizes specifics cores. The presence, on all types of bladelets, of micro use-wear corroborates the intentionality of these productions. The use-wear show that the bladelets have been used for various actions in and on different materials worked and that they were maintained according to different modes of prehension. Across the Levant, a technical continuity clearly appears between the facies of the intermediate Palaeolithic and the industries of the upper Palaeolithic: the Ahmarian and the Aurignacian. Nevertheless this technical innovation is integrated in a distinct way according to the considered period. During the intermediate Palaeolithic the lithics productions are different according to the facies and the use of the bladelets is varied. While during the upper Palaeolithic there is a technical normalization of the blanks but also functions of bladelets.  相似文献   

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