The Study of Cutaneous Melanomas in Camargue‐Type Gray‐Skinned Horses (1): Clinical–Pathological Characterization

The clinical and pathological characteristics of cutaneous melanomas occurring in Camargue‐type gray‐skinned horses are reported. Examination of 83 tumor‐bearing horses revealed that the tumors occurred most frequently underneath the tail (93.9%) and at high rates in the peri‐anal region (43.0%), the lips (33.0%), and the eyelids (24.0%), but rarely in the vulva (3.8%). Tumorous lesions were characterized by the presence of either hemispheric nodules or large infiltrated plaques, or their combinations. Microscopic examination indicated that tumorous lesions were composed mostly of melanocytes and numerous melanophages and that component cells manifested a remarkable cellular atypia with anisocytosis and anisokarinosis. Pathological examination of lesions corresponding to earlier stages of the tumors disclosed that tumor formation and its related melanogenesis occurred in close topographical association with apocrine sweat glands, but not at the dermal–epidermal junction. Larger nodules of the tumors were often composed of a concentric deposition of cell layers, each being separated by dermal components from the epidermis. Because of the absence of their tropism toward the epidermis and their multiloculation, horse melanomas are considered to be different in their pathological characteristics from human melanomas.     

1 July 1858: what Wallace knew; what Lyell thought he knew; what both he and Hooker took on trust; and what Charles Darwin never told them

At the Linnean Society on 1 July 1858, Charles Lyell and Joseph Hooker, using only an extract from Charles Darwin's unpublished essay of 1844, and a copy of a recent letter to Asa Gray in Boston, argued successfully that Darwin understood how species originate long before a letter from Alfred Russel Wallace outlining his own version of the theory of evolution arrived at Darwin's home. That letter from Ternate in the Malay Archipelago, however, was not the first letter Darwin received from Wallace. This article will contend that two of the three letters Wallace sent Darwin between 10 October 1856 and 9 March 1858 arrived much earlier than Darwin recorded, thereby allowing him time to assess Wallace's ideas and claim an independent understanding of how the operation of divergence and extinction in the natural world leads strongly marked varieties to be identified as new species. By the time of the Linnean meeting Darwin's new ideas had filtered into his letters and ‘big’ species book, despite the absence of any independent evidence from the natural world to justify his constant insistence to have been guided only by inductive reasoning. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109 , 725–736.     

New fossil fruits of Carya (Juglandaceae) from the latest Miocene to earliest Pliocene in Tennessee,eastern United States

Fossil fruits including nuts and associated husk valves of a new species of Carya (Juglandaceae) are described from the latest Miocene to earliest Pliocene in northeastern Tennessee, eastern United States. The husk valves are elliptic, 1.2–4.5 mm thick, with a convex exterior face and a concave interior face; the nuts are globose to ovoid in shape, smooth and longitudinally ribbed on exterior surface, with a short protruding apex and a slightly 4-angled base; inner ribs, lacunae and primary septa are well-developed, while secondary septa are absent or weakly developed. The combination of these carpological characteristics clearly shows a close resemblance to the genus Carya in Juglandaceae. Detailed comparisons of carpological morphology and anatomy indicate that the present fossil taxon is different from both living and most other fossil species of the genus, and therefore warrants the designation of a new fossil species, Carya tennesseensis Huang et al., sp. nov. Carya tennesseensis displays a carpological similarity to C. ventricosa from the late Oligocene to early Pliocene in Europe, suggesting a potential species exchange of the genus between Europe and southeastern North America during the late Neogene. The new fossil species represents one of the few fruit fossil species of Carya from its modern distribution range in southeastern North America. It provides crucial information for better understanding the rapid diversification of the genus from the late Miocene to early Pliocene, and the origin and establishment of today's Carya biodiversity in this region.     

国产毛莨属11种及其4个近缘属5种植物的细胞学研究

研究了国产毛莨属RanunculusL.11种及其4个远缘属－美花草属CollianthemunC.A.Meyer,侧金盏花属AdonisL．、碱毛莨属Halerpestes E.Greene,水毛莨属BatrachiumS.F.Gray5种植物的洒色体数目和形态。发现美花草C.pinpinelloides(D.Don)Hook.f.et THoms.,川滇毛莨R.potaninii Kom.,深齿毛莨R.popovii var.stracheyanus(Maxim.)W.T.Wang,高原毛莨R.tanguticus(Maxim.)Ovcx., 石龙芮R.sceleratusL.,西南毛莨R.ficariifolius Levl.et Vant.、褐鞘毛莨R.sinovaginatus W.T.Wang、三裂碱毛莨H.tricuspis(Maxim.)Hand.-Mazz.和碱毛莨H.sarmentosa（Adams)Kom.9种植物为染色体基数x=8的四倍体（2n=4x=32）;短注侧金盏花A.brevistyla Franch．、丝叶毛莨R.nematolobus Hand.-Mass.、棱喙毛莨3R.trigonus Hand.-Mazz.、 茴茴蒜R.chinensis Bunge4种植物为染色体基数x=8的二倍体(2n=2x=16);毛莨R.japonicus Thunb.、黄毛莨R.laetus Wall.2种植物为染色体基数x=7的二倍体（2n=2x=14);水毛莨B.bungei(Steud.)L.Liou有二倍体（2n=2x=16)和三倍体（2n=3x=24)两种细胞型。根据染体资料,讨论了上述5属的属间关系和毛莨属中一些种的种间关系。     

Genetic mapping of gray leaf spot (GLS) resistance genes in maize

Bulked segregant analysis was used to identify amplified fragment length polymorphism markers (AFLPs) linked to quantitative trait loci (QTLs) involved in the resistance to gray leaf spot (GLS) in maize. By using ten AFLP primer combinations 11 polymorphic markers were identified and converted to sequence- specific PCR markers. Five of the 11 converted AFLPs were linked to three GLS resistance QTLs. The markers were mapped to maize chromosomes 1, 3 and 5 using existing linkage maps of two commercially available recombinant inbred-line populations. Converted restriction fragment length polymorphism markers and microsatellite markers were used to obtain a more-precise localization for the detected QTLs. The QTL on chromosome 1 was localized in bin 1.05/06 and had a LOD score of 21. A variance of 37% was explained by the QTL. Two peaks were visible on chromosome 5, one was localized in bin 5.03/04 and the other in bin 5.05/06. Both peaks had a LOD score of 5, and 11% of the variance was explained by the QTLs. A variance of 8–10% was explained by the QTL on chromosome 3 (bin 3.04). The consistency of the QTLs was tested across two F₂ populations planted in consecutive years. Received: 10.10.00 / Accepted: 26.01.01     

中国睡莲科一新记录属--水盾草属

睡莲科水盾草属,迄今在我国尚未见报道,作者先后在青浦和吴县等地调查植物时,采集到水盾草属的竹节水松（鱼草）。这一发现不仅丰富了我国的植物种类、区系成份和资源植物,而且对《中国植物志》的修订再版和植物资源的开发利用提供了新信息     

棕背树蜥不同组织三种同工酶之间的差异研究

文章采用垂直板聚丙烯酰胺凝胶电泳方法,研究了分布在广东韶关地区的棕背树蜥(CalotesemmaGray)的肝脏、肌肉、心脏、脑、生殖腺五种组织酯酶(EST)、淀粉酶(AMY)和过氧化氢酶(CAT)三种同工酶,研究结果,酯酶(EST)同工酶有两条共有的酶带,Rf8除了肝脏不具备外,心脏、肌肉、脑和性腺共有,体现肝脏的特异性,性腺酶带有明显的性别差异;淀粉酶(AMY)同工酶有一条共同酶带,肝脏酶带最为复杂,其次是生殖腺和雌体心脏,五种组织中有三种组织出现雌雄差异;过氧化氢酶(CAT)有两条共有的酶带,肝脏和生殖腺的酶带复杂,而且出现明显的性别差异性,心脏、肌肉和脑酶带相似,呈现不同组织的同源性.上述果表明三种同工酶在不同的组织表现出明显的同源性和差异性,雌雄个体间同一种酶表现出性别差异。     

鲻和鲮鳃丝的扫描电镜比较观察

对鲻（Mugil cephalus）和鲮（Cirrhina molitorella）的鳃丝表面结构进行了扫描电镜比较观察,结果表明,鲻鳃丝杆状部比鲮粗．鲻鳃小片高度比鲮低;两者鳃丝表面分泌孔洞口径和密度不同;鲻和鲮细胞外被不同,鲻细胞外被稀疏,鲮的则致密复杂;鳃小片细胞和鳃丝表皮细胞的表面形态存在差异,文章还描述了鳃丝表皮形态特异的细胞。     

黄土区森林植被对坡面径流和侵蚀产沙的影响

根据山西省吉县蔡家川流域198～2003年9个径流小区的降雨产流产沙的定位观测资料,分析了植被对流域坡面尺度降雨产流产沙的影响.结果表明,坡面自然更新的次生林比人工刺槐林具有更好的涵养水源和保持水土功能,场降雨产流量和产沙量分别减少约65%～82%和23%～92%;多元回归分析表明,场降雨产流量和产沙量与降雨量和雨强均呈良好的相关关系,但随着林分郁闭度增大,相关关系减小.不同地类的降雨产流产沙差异显著,虎榛子灌木林和天然次生林最少,而人工刺槐、油松林约是虎榛子灌木林的倍,果农复合经营模式的产流产沙量分别是虎榛子灌木林的17.14倍和3.96倍;果农复合经营模式在高质量、大工程整地后产流产沙明显减少.对坡面产流产沙的影响因子灰色关联分析,林分郁闭度和草本、枯落物生物量对坡面产流产沙影响显著,关联度值均大于0.6.     

中华鲟授精过程扫描电镜观察

在扫描电镜下观察到:中华鲟的成熟卵具有一层放射膜,两层卵黄膜;卵的动物极端有9—15个受精孔,受精孔直径约为12.7—13.9μm;精子由伞状顶体、棍棒状头部、漏斗状中段及扁平细长的尾部组成;各受精孔都能接纳多个精子;卵受精5秒后,精子才开始入卵,且精子入卵速度各不相同。受精时间持续较长,可由5秒延长至5分钟;卵受梢后,受精管道内除缠绕成团的精子尾部外,未发现其他堵塞物。