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排序方式: 共有369条查询结果,搜索用时 15 毫秒
321.
Van Houdt JK Nowakowska BA Sousa SB van Schaik BD Seuntjens E Avonce N Sifrim A Abdul-Rahman OA van den Boogaard MJ Bottani A Castori M Cormier-Daire V Deardorff MA Filges I Fryer A Fryns JP Gana S Garavelli L Gillessen-Kaesbach G Hall BD Horn D Huylebroeck D Klapecki J Krajewska-Walasek M Kuechler A Lines MA Maas S Macdermot KD McKee S Magee A de Man SA Moreau Y Morice-Picard F Obersztyn E Pilch J Rosser E Shannon N Stolte-Dijkstra I Van Dijck P Vilain C Vogels A Wakeling E Wieczorek D 《Nature genetics》2012,44(4):445-9, S1
322.
Iain R. Murray Christopher C. West Winters R. Hardy Aaron W. James Tea Soon Park Alan Nguyen Tulyapruek Tawonsawatruk Lorenza Lazzari Chia Soo Bruno Péault 《Cellular and molecular life sciences : CMLS》2014,71(8):1353-1374
Mesenchymal stem/stromal cells (MSCs) can regenerate tissues by direct differentiation or indirectly by stimulating angiogenesis, limiting inflammation, and recruiting tissue-specific progenitor cells. MSCs emerge and multiply in long-term cultures of total cells from the bone marrow or multiple other organs. Such a derivation in vitro is simple and convenient, hence popular, but has long precluded understanding of the native identity, tissue distribution, frequency, and natural role of MSCs, which have been defined and validated exclusively in terms of surface marker expression and developmental potential in culture into bone, cartilage, and fat. Such simple, widely accepted criteria uniformly typify MSCs, even though some differences in potential exist, depending on tissue sources. Combined immunohistochemistry, flow cytometry, and cell culture have allowed tracking the artifactual cultured mesenchymal stem/stromal cells back to perivascular anatomical regions. Presently, both pericytes enveloping microvessels and adventitial cells surrounding larger arteries and veins have been described as possible MSC forerunners. While such a vascular association would explain why MSCs have been isolated from virtually all tissues tested, the origin of the MSCs grown from umbilical cord blood remains unknown. In fact, most aspects of the biology of perivascular MSCs are still obscure, from the emergence of these cells in the embryo to the molecular control of their activity in adult tissues. Such dark areas have not compromised intents to use these cells in clinical settings though, in which purified perivascular cells already exhibit decisive advantages over conventional MSCs, including purity, thorough characterization and, principally, total independence from in vitro culture. A growing body of experimental data is currently paving the way to the medical usage of autologous sorted perivascular cells for indications in which MSCs have been previously contemplated or actually used, such as bone regeneration and cardiovascular tissue repair. 相似文献
323.
Alan C. Taye 《西北部美国博物学家》2011,43(4)
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} The Stansbury Mountains of north central Utah rise over 2000 m above surrounding desert valleys to a maximum elevation of 3362 m on Deseret Peak. Because of the great variety of environmental conditions that can be found in the Stansburys, a wide range of plant species and vegetation types (from shadscale desert to alpine meadow) exist there. This paper presents an annotated list of 594 vascular plant species in 315 genera and 78 families. The largest families are Asteraceae (98 species), Poaceae (71), Brassicaceae (33), Fabaceae (27), and Rosaceae (26). Elymus flavescens was previously unreported from Utah. Statistical comparison of the Stansbury flora with neighboring mountain floras indicates that the Wasatch Mountains lying 65 km to the east have probably been the primary source area for development of the Stansbury flora. Many lowland species, especially those inhabiting sandy areas, apparently have migrated to the area from the south. 相似文献
324.
Bicknell LS Bongers EM Leitch A Brown S Schoots J Harley ME Aftimos S Al-Aama JY Bober M Brown PA van Bokhoven H Dean J Edrees AY Feingold M Fryer A Hoefsloot LH Kau N Knoers NV Mackenzie J Opitz JM Sarda P Ross A Temple IK Toutain A Wise CA Wright M Jackson AP 《Nature genetics》2011,43(4):356-359
Meier-Gorlin syndrome (ear, patella and short-stature syndrome) is an autosomal recessive primordial dwarfism syndrome characterized by absent or hypoplastic patellae and markedly small ears1?3. Both pre- and post-natal growth are impaired in this disorder, and although microcephaly is often evident, intellect is usually normal in this syndrome. We report here that individuals with this disorder show marked locus heterogeneity, and we identify mutations in five separate genes: ORC1, ORC4, ORC6, CDT1 and CDC6. All of these genes encode components of the pre-replication complex, implicating defects in replication licensing as the cause of a genetic syndrome with distinct developmental abnormalities. 相似文献
325.
Loveday C Turnbull C Ramsay E Hughes D Ruark E Frankum JR Bowden G Kalmyrzaev B Warren-Perry M Snape K Adlard JW Barwell J Berg J Brady AF Brewer C Brice G Chapman C Cook J Davidson R Donaldson A Douglas F Greenhalgh L Henderson A Izatt L Kumar A Lalloo F Miedzybrodzka Z Morrison PJ Paterson J Porteous M Rogers MT Shanley S Walker L;Breast Cancer Susceptibility Collaboration 《Nature genetics》2011,43(9):879-882
Recently, RAD51C mutations were identified in families with breast and ovarian cancer. This observation prompted us to investigate the role of RAD51D in cancer susceptibility. We identified eight inactivating RAD51D mutations in unrelated individuals from 911 breast-ovarian cancer families compared with one inactivating mutation identified in 1,060 controls (P = 0.01). The association found here was principally with ovarian cancer, with three mutations identified in the 59 pedigrees with three or more individuals with ovarian cancer (P = 0.0005). The relative risk of ovarian cancer for RAD51D mutation carriers was estimated to be 6.30 (95% CI 2.86-13.85, P = 4.8 × 10(-6)). By contrast, we estimated the relative risk of breast cancer to be 1.32 (95% CI 0.59-2.96, P = 0.50). These data indicate that RAD51D mutation testing may have clinical utility in individuals with ovarian cancer and their families. Moreover, we show that cells deficient in RAD51D are sensitive to treatment with a PARP inhibitor, suggesting a possible therapeutic approach for cancers arising in RAD51D mutation carriers. 相似文献
326.
327.
现代社会要求理工科学生在大学教育中逐渐掌握各种科学研究的手段及个人技能,以满足21世纪的需要.我们描述了一个帮助学生发展这种技能及在实际科学研究中的认知过程,系统技术在这个学习系统的许多方面起到非常重要的作用,我们描述了在各种国际测量表中描述的教育目标,描述了部分满足这个目标的学习系统,描述了技术在这个系统中的作用以及这个学习系统的有效性评估. 相似文献
328.
329.
Cell electrophoretic mobilities in Friend virus disease 总被引:2,自引:0,他引:2
330.
In previous research much effort has been devoted to the geometry of woven fabrics and relat-ed problems under the assumption of constant yarn configuration in fabric.This paper will first re-port that image crimp (yarn crimp measured by an image analysis method) seems larger than actualvalue.From the explanation of this result,the variation of yarn configuration in woven fabric dueto the non-uniform flattening is revealed.The significance of this actual structure of woven fabricsis discussed.It is believed that the variation of yarn configuration is very important for fabric per-formance,and may be an advantage for fabric quality. 相似文献