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111.
傅卓凌 《现代生物医学进展》2007,7(6):960-960,945
本文报道1例乳腺癌复发转移牙龈的诊断,提示乳腺癌的转移通常为区域淋巴结转移,也可经血液远处转移,最常见的远处转移部位为肺、肝、骨等,转移至牙龈的则十分罕见,牙龈上的转移癌早期表现与牙龈瘤极为相似,容易误诊。详细地询问病史极为重要,穿刺细胞学检查有助于明确诊断,必要时可以在术中冰冻活检,明确诊断后按一般恶性肿瘤的治疗原则手术治疗。 相似文献
112.
Telocytes in minor salivary glands of primary Sjögren's syndrome: association with the extent of inflammation and ectopic lymphoid neogenesis 下载免费PDF全文
Alessia Alunno Lidia Ibba‐Manneschi Onelia Bistoni Irene Rosa Sara Caterbi Roberto Gerli Mirko Manetti 《Journal of cellular and molecular medicine》2015,19(7):1689-1696
It has been recently reported that telocytes, a stromal (interstitial) cell subset involved in the control of local tissue homeostasis, are hampered in the target organs of inflammatory/autoimmune disorders. Since no data concerning telocytes in minor salivary glands (MSGs) are currently available, aim of the study was to evaluate telocyte distribution in MSGs with normal architecture, non‐specific chronic sialadenitis (NSCS) and primary Sjögren's syndrome (pSS)‐focal lymphocytic sialadenitis. Twelve patients with pSS and 16 sicca non‐pSS subjects were enrolled in the study. MSGs were evaluated by haematoxylin and eosin staining and immunofluorescence for CD3/CD20 and CD21 to assess focus score, Tarpley biopsy score, T/B cell segregation and germinal center (GC)‐like structures. Telocytes were identified by immunoperoxidase‐based immunohistochemistry for CD34 and CD34/platelet‐derived growth factor receptor α double immunofluorescence. Telocytes were numerous in the stromal compartment of normal MSGs, where their long cytoplasmic processes surrounded vessels and encircled both the excretory ducts and the secretory units. In NSCS, despite the presence of a certain degree of inflammation, telocytes were normally represented. Conversely, telocytes were markedly reduced in MSGs from pSS patients compared to normal and NSCS MSGs. Such a decrease was associated with both worsening of glandular inflammation and progression of ectopic lymphoid neogenesis, periductal telocytes being reduced in the presence of smaller inflammatory foci and completely absent in the presence of GC‐like structures. Our findings suggest that a loss of MSG telocytes might have important pathophysiological implications in pSS. The specific pro‐inflammatory cytokine milieu of pSS MSGs might be one of the causes of telocyte loss. 相似文献
113.
Emily B. Blackman Christopher S. Deperno Ron W. Heiniger Matthew J. Krachey Christopher E. Moorman M. Nils Peterson 《The Journal of wildlife management》2012,76(3):528-533
Since the late 1960s, American woodcock (Scolopax minor) have undergone population declines because of habitat loss. Previous research suggested ridge and furrow topography in conventionally tilled soybean fields provided critical nocturnal cover as birds foraged on earthworms. However, the use of no-till technology has increased and many fields now lack ridge and furrow topography. We assessed woodcock winter nocturnal foraging habitat use given recent changes in agricultural technology, and investigated how field treatment, earthworm abundance, and environmental variables affect the selection of nocturnal foraging sites. We counted woodcock along transects in 5 field treatments twice in each of 67 fields during December–March 2008–2009 and 72 fields during December–March 2009–2010. During both seasons, we collected earthworm and soil samples from a subset of fields of each field treatment. Woodcock densities were at least twice as high in no-till soybean fields planted after corn and in undisked corn fields with mowed stalks than in other field treatments. No-till soybean planted after corn and undisked corn fields contained ridge and furrow topography, whereas other crops did not, and earthworms were at least 1.5 times more abundant in no-till soybean fields than other field treatments. Ridges and furrows in no-till soybean fields planted after corn and undisked corn fields may provide wintering woodcock with thermal protection and concealment from predators. No-till soybean fields planted after corn offered the additional benefit of relatively high food availability. The presence of ridge and furrow topography can be used to predict woodcock field use on the wintering grounds in agricultural areas. Farmers can provide nocturnal winter foraging sites for woodcock by delaying field disking and leaving ridge and furrow topography in crop fields. © 2011 The Wildlife Society. 相似文献
114.
Regulation of sulfate assimilation in Arabidopsis and beyond 总被引:2,自引:0,他引:2
Kopriva S 《Annals of botany》2006,97(4):479-495
BACKGROUND AND AIMS: Sulfate assimilation is a pathway used by prokaryotes, fungi and photosynthetic organisms to convert inorganic sulfate to sulfide, which is further incorporated into carbon skeletons of amino acids to form cysteine or homocysteine. The pathway is highly regulated in a demand-driven manner; however, this regulation is not necessarily identical in various plant species. Therefore, our knowledge of the regulation of sulfate assimilation is reviewed here in detail with emphasis on different plant species. SCOPE: Although demand-driven control plays an essential role in regulation of sulfate assimilation in all plants, the molecular mechanisms of the regulation and the effects of various treatments on the individual enzymes and metabolites are often different. This review summarizes (1) the molecular regulation of sulfate assimilation in Arabidopsis thaliana, especially recent data derived from platform technologies and functional genomics, (2) the co-ordination of sulfate, nitrate and carbon assimilations in Lemna minor, (3) the role of sulfate assimilation and glutathione in plant-Rhizobia symbiosis, (4) the cell-specific distribution of sulfate reduction and glutathione synthesis in C(4) plants, (5) the regulation of glutathione biosynthesis in poplar, (6) the knock-out of the adenosine 5'phosphosulfate reductase gene in Physcomitrella patens and identification of 3'-phosphoadenosyl 5'-phosphosulfate reductase in plants, and (7) the sulfur sensing mechanism in green algae. CONCLUSIONS: As the molecular mechanisms of regulation of the sulfate assimilation pathway are not known, the role of Arabidopsis as a model plant will be further strengthened. However, this review demonstrates that investigations of other plant species will still be necessary to address specific questions of regulation of sulfur nutrition. 相似文献
115.
116.
福建省兴化湾黑脸琵鹭的越冬及迁徙 总被引:3,自引:2,他引:1
福建省兴化湾是我国大陆黑脸琵鹭(Platalea minor)最重要的越冬地之一.2005年1月至2008年4月连续4个冬季的调查显示,在湾内的江镜华侨农场越冬的黑脸琵鹭种群数量为40~60只,其中2007年越冬种群的数量较前3个冬季显著增加.黑脸琵鹭主要栖息在农场面积约320 hm2的养殖塘内,多集群.昼间栖息的各种行为中休息行为所占比例最高,达到80%;其次是维护行为,约10%;觅食等其他行为所占的比例很低,因此养殖塘主要作黑脸琵鹭昼间的休息场所之用.兴化湾同时是黑脸琵鹭重要的迁徙停歇地,2007年秋季南迁的时间为11月3日至12月12日;2008春季北迁的时间为3月8日至4月加日.江镜华侨农场南迁停歇的种群数量约为136只,北迁的数量约为226只.春季北迁种群中具繁殖羽的个体比例最高时超过60%,表明种群中能够参与繁殖的个体数量较多.建议加强兴化湾滩涂及养殖塘人工湿地的科学管理,促进黑脸琵鹭的保护. 相似文献
117.
118.
于2005~2006年在辽宁省千山利用信息化学物质野外诱捕黄色梢小蠹Gryphalus fulvus、红松根小蠹Hylastes plumbeus、横坑切梢小蠹Tomicus minor及纵坑切梢小蠹Tomicus piniperda成虫,结果显示:这4种小蠹在4月18日至8月10日期间都明显出现2次扬飞高峰。第1次扬飞高峰持续均为30d左右,第2次扬飞高峰期约为15d;黄色梢小蠹和红松根小蠹第1次扬飞高峰期在5月上中旬出现,第2次扬飞高峰期分别在7月中下旬和上中旬;横坑切梢小蠹与纵坑切梢小蠹的扬飞高峰期基本一致,第1次扬飞高峰期为4月下旬到5月上旬,第2次扬飞高峰在7月上中旬;结果同时还表明诱虫量第1次扬飞高峰一般都明显大于第2次,只是黄色梢小蠹在首次利用信息化学物质进行监测且密度较高时例外。 相似文献
119.
Oncolytic adenoviruses represent a promising therapeutic medicine for human cancer therapy, but successful translation into human clinical trials requires careful evaluation of their viral characteristics. While the function of adenovirus proteins has been analyzed in detail, the dynamics of adenovirus infection remain largely unknown due to technological constraints that prevent adequate tracking of adenovirus particles after infection. Fluorescence labeling of adenoviral particles is one new strategy designed to directly analyze the dynamic processes of viral infection in virus-host cell interactions. We hypothesized that the double labeling of an adenovirus with fluorescent proteins would allow us to properly analyze intracellular viruses and the fate of viral proteins in a live analysis of an adenovirus as compared to single labeling. Thus, we generated a fluorescently labeled adenovirus with both a red fluorescent minor capsid protein IX (pIX) [pIX monomeric red fluorescent protein 1 (mRFP1)] and a green fluorescent minor core protein V (pV) [pV enhanced green fluorescent protein (EGFP)], resulting in Ad5-IX-mRFP1-E3-V-EGFP. The fluorescent signals for pIX-mRFP1 and pV-EGFP were detected within 10 min in living cells. However, a growth curve analysis of Ad5-IX-mRFP1-E3-V-EGFP showed an approximately 150-fold reduced production of the viral progeny at 48 h postinfection as compared to adenovirus type 5. Interestingly, pIX-mRFP1 and pV-EGFP were initially localized in the cytoplasm and nucleolus, respectively, at 18 h postinfection. These proteins were observed in the nucleus during the late stage of infection, and relocalization of the proteins was observed in an adenoviral-replication-dependent manner. These results indicate that simultaneous detection of adenoviruses using dual-fluorescent proteins is suitable for real-time analysis, including identification of infected cells and monitoring of viral spread, which will be required for a complete evaluation of oncolytic adenoviruses. 相似文献
120.
Edward N. Trifonov 《Journal of theoretical biology》2010,263(3):337-10
DNA deformation in the nucleosome involves partial unstacking between bases and base pairs. By adjusting orientations of different base-pair stacks relative to the histone octamer surface, the optimal set of stacks and their positions is derived, resulting in a sequence pattern, theoretically best suitable for nucleosome DNA. The sequence is very much consistent with available experimental data, thus, suggesting a common eukaryotic nucleosome DNA bendability sequence pattern based exclusively on the very basics of DNA. 相似文献