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1.
A sequence of nine, plant-macrofossil-bearing horizons has been recognized in the Lower Oligocene from the Isle of Wight, England. The plant fossils are contained in finely laminated, olive-brown to black silty-clays and clays. Some horizons exhibit rhythmic alternation of sediment couplets; others show evidence of bioturbation and rootlet penetration. These horizons are included within a sequence of finely laminated greenish grey silty-clays and clays, largely devoid of plant macrofossil material. The plant-bearing horizons contain abundant fruits, seeds, fern sporangia, Azolla megaspores, and rare leaves. The nearest living relatives of the fossils all inhabit an aquatic or marginal aquatic environment. The associated fossil fauna includes lake bottom and lake margin species. The palynoflora of the plant-bearing and immediately underlying horizons includes large numbers of planktonic algae and limited representatives of a forest vegetation. It shows a strong relationship between the occurrences of Sparganiaceaepollenites pollen and of Typha macrofossils. Palaeoecological interpretations of this plant-fossil-bearing sequence are discussed with particular reference to modern environments.
One new genus and three new species are described. Emendations are presented for four other species. Stratiotes leaf margin teeth are described.  相似文献   

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A new fossil spider, Vectaraneus yulei gen. et sp. nov., from the Eocene Bembridge Marls Insect Bed of the Isle of Wight, shows internal anatomy, including book lungs and tracheae, preserved by calcium carbonate replacement. The wide, medially positioned, tracheal spiracle and large tracheae which enter the prosoma are adaptations for an amphibious mode of life. The spider is placed in Cybaeidae Simon, 1898, Argyronetinae Menge, 1869, a subfamily which includes the Recent European Water Spider, Argyroneta aquatica (Clerck, 1757). The only previously described Bembridge Marls spider, Eoatypus woodwardii McCook, 1888, is redescribed; it is unrelated to Vectaraneus . The holotype of Argyroneta antiqua Von Heyden (1859) is redescribed; it is not an Argyroneta . Specimens referred to A. antiqua by Bertkau (1878) probably belong in Argyronetinae Menge, 1869, and this subfamily is emended herein.  相似文献   

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The variation in the radula of three species of Lacuna has been investigated and the back of the rachidian tooth is proposed as providing a new character set of potentially high taxonomic value. The term basal plate is introduced for the back of the rachidian tooth. Cusp and tooth morphology are closely related to diet and wear, and are subject to considerable homoplasy, whereas the structure of the basal plate of the rachidian tooth provides a more neutral character set. The difference in this character set between the lacunids has been quantified using seven measurements and the exploratory multivariate statistical procedure principal component analysis. The basal plate of the rachidian tooth showed interspecific differences. The taxonomic value of this new character set should be evaluated in further studies of other prosobranchs. Received in revised form: 25 October 2000 Electronic Publication  相似文献   

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A 55-year old man without immunosuppression clinically showed a coin lesion in the right lower lung on the chest radiographs.Aspergillus nidulans was isolated and identified in both trans-bronchial lung biopsy specimen and resected tissue. The specimens revealed characteristics of chronic necrotizing pulmonary aspergillosis pathologically. Very few reports on cases of pulmonary aspergillosis due toA. nidulans exist, and we were not able to find any reports of similar cases. This case may be the first reported case of chronic necrotizing pulmonary aspergillosis due toA. nidulans.  相似文献   

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报道面部糖皮质激素依赖性皮炎伴难辨认癣1例.患者男,40岁,面部弥漫红斑、脱屑、丘疹,伴瘙痒、灼热症状,反复发作7a.曾在外院被诊断为脂溢性皮炎、湿疹、接触性皮炎,给予多种糖皮质激素药膏外用.取面部皮屑做真菌直接镜检为阳性,经鉴定为红色毛癣菌.诊断为面部激素依赖性皮炎、难辨认癣.给予伊曲康唑100 mg/次,2次/d,口服;第1周给予曲安奈德益康唑乳膏2次/d外用;第2周给予舍他康唑2次/d外用.2周后患者皮损明显好转,停用口服药物,给予他克莫司1次/d外用.4周后,患者皮损达临床治愈.  相似文献   

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报道临床表现类似脂溢性皮炎的头癣1例。患儿5岁,因头皮丘疹半年、鳞屑增多并脱落半个月就诊。刮取皮屑、病发直接镜检查见菌丝和发内孢子,对鳞屑、病发培养有紫色菌落生长,转种作小培养后光镜下观察见菌丝粗细不一,分隔、分支多,并有不规则突起,间生厚壁孢子多见,鉴定为紫色毛癣菌。经内服和外用特比萘芬治疗3周后痊愈。  相似文献   

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Capsule: Overall numbers of Peregrines are higher than previously recorded, due primarily to the growth of lowland populations, despite declines in many upland areas.

Aims: To estimate the breeding population of Peregrines, and changes in this population over time, as well as to relate variation in trends and observed breeding success to variation in region, breeding site type and other ecological influences.

Methods: Two types of survey methods were used. Site-based visits focussed on locations where Peregrines were known to have bred previously, while area-based searches aimed to find all Peregrines breeding in randomly chosen 5?km?×?5?km squares. Findings from each method were used to estimate population size in different parts of the survey area. Breeding outcome and site type were assessed for most of the pairs found during either survey.

Results: In 2014, the breeding population of Peregrines in the UK, Isle of Man and Channel Islands was estimated at 1769 pairs. This is 22% larger than the population estimate from the previous survey in 2002. Most of this increase is accounted for by increases in lowland England. Populations in some upland areas have declined.

Conclusions: The gap between the fortunes of lowland and upland Peregrines has continued to grow, along with the overall UK population. Likely reasons for the continued success of Peregrines in the lowlands include increasing uptake of breeding sites on human structures, abundant availability of prey in many lowland situations and, in many areas, a relative lack of conflict with humans. Factors likely to be limiting upland Peregrine populations vary between different regions, and include ongoing illegal killing and deliberate disturbance, and food supply.  相似文献   

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Over the last few years, new Malassezia species have been found regularly in Japanese subjects. We isolated another new Malassezia species from a Japanese patient with seborrheic dermatitis (SD), and named it M. yamatoensis. In its physiological characteristics and the utilization of Tween by M. yamatoensis is similar to that of M. furfur and M. dermatis. It is distinguished by its growth temperature. To examine the distribution of the microorganism in the skin of patients with SD and atopic dermatitis (AD), and healthy subjects, we applied transparent dressings to the skin, and detected M. yamatoensis DNA using a non-culture-based method that consisted of nested PCR with specific primers. M. yamatoensis DNA was detected from 3 of 31 SD patients (9.7%), 5 of 36 AD patients (13.9%), and 1 of 22 healthy subjects (4.6%). Therefore, M. yamatoensis is a rare member of the cutaneous microflora.  相似文献   

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The Wessex Formation on the Isle of Wight yields an Early Cretaceous dinosaur fauna. Sedimentological evidence shows that this represents a mosaic of fluvial, floodplain and lacustrine environments within a relatively narrow east-west oriented valley. The vegetational cover on the alluvial plain had a savannah-or chaparral-like aspect, probably of low productivity. The relative scarcity of small aquatic vertebrates, absence of coals, abundance of oxidixed sediments and the presence of immature calcretes indicate seasonal water supply. The dinosaur taxa compising the Wessex Formation faunal assemblage represent a single palaeocommunity which inhabited the local alluvial plain, although some species may have been transient. The fauna had a relatively low diversity and this is attributed to the low productivity of the local vegetation. Iguanodontids and Hypsilophodon were the dominant elements in the fauna. In contrast to Late Jurassic dinosaur faunas, sauropods are less abundant in the Wessex Formation, although they remain taxonomically diverse. It is concluded that climatic changes which took place in the Late Jurassic or Early Cretaceous resulted in the appearance of low productivity vegetation and that this was incapable of supporting large sauropod populations.  相似文献   

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An unusual case of discontinuous hard tissue hyperostosis is described in a 25-30–year-old female dating between 4000 and 5500 BP from northern Chile. This specimen was one of 104 individuals examined from the Morro-1 site, which is known to represent the Chinchorro culture. The only other reported case from antiquity dates to 500 AD (Lester [1969] J. Bone Joint Surg. [Am.] 49:142–143). A review and comparison of this case to the medical literature supports a diagnosis of melorheostosis. Differential diagnosis is presented with the ruling out of nonspecific manifestations of osteomyelitis/periostitis as the most likely alternative diagnosis. © 1995 Wiley-Liss, Inc.  相似文献   

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The Oligocene Malembo locality, Cabinda exclave, Angola, has yielded a rich vertebrate fauna represented by fragmentary remains. This fossiliferous locality is the only definite occurrence of Oligocene terrestrial mammals in sub-Saharan West Africa. The hyracoids from Malembo have only been very succinctly described and compared thus far, so that their systematic attribution is not consensual among specialists. A revision now allows the identification of three (or four) medium to large-sized species represented by Geniohyus dartevellei, Pachyhyrax cf. crassidentatus, and two undetermined taxa. The species G. dartevellei is revived for the holotype of Palaeochoerus dartevellei Hooijer, 1963; this species is unique to Malembo but appears close to Geniohyus mirus, a species only known from the early Oligocene of the Fayum, Egypt. Other species of Geniohyus and Pachyhyrax crassidentatus are also only known from the early Oligocene of the Fayum. The presence of Geniohyus and Pachyhyrax cf. crassidentatus at Malembo thus supports an early Oligocene age for the fauna.  相似文献   

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Birth weight has been linked to the risk of developing childhood cancer, in particular childhood leukaemia. However, despite many childhood cancers having a male predominance and boys generally weighing more than girls at birth few studies have reported sex-specific associations. The relationship between birth weight and childhood cancer risk was examined using information from a national case-control study. Children (0–14 years) newly diagnosed with cancer in GB were ascertained between 1991 and 1996 (n = 3651) and for comparison, controls matched on sex, month and year of birth were identified from primary care population registers (n = 6337). Birth weights were obtained from the Office of National Statistics for all targeted subjects born in England and Wales. Overall, cases were, on average, 30 g heavier at birth than controls (p = 0.003) with differences seen by cancer type; those diagnosed with hepatic tumours weighing around 500 g less than controls at birth (p < 0.0001) and those with leukaemia being, on average, 50 g heavier than those without (p = 0.001). An interaction between birth weight and sex was found for acute leukaemia (χ2 = 11.2, p = 0.04) and when data were stratified by sex, an association between high birth weight and risk of ALL was seen with girls (>4000 g, OR 1.86, 95% CI 1.38–2.50, χ2 for trend 20.2, p < 0.0001). Our results support the hypothesis that birth weight is an important determinant for childhood cancer. In addition, the data are consistent with the notion that childhood leukaemia has a prenatal origin.  相似文献   

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Several quantitative trait loci (QTLs) that influence developmental dyslexia (reading disability [RD]) have been mapped to chromosome regions by linkage analysis. The most consistently replicated area of linkage is on chromosome 6p23-21.3. We used association analysis in 223 siblings from the United Kingdom to identify an underlying QTL on 6p22.2. Our association study implicates a 77-kb region spanning the gene TTRAP and the first four exons of the neighboring uncharacterized gene KIAA0319. The region of association is also directly upstream of a third gene, THEM2. We found evidence of these associations in a second sample of siblings from the United Kingdom, as well as in an independent sample of twin-based sibships from Colorado. One main RD risk haplotype that has a frequency of approximately 12% was found in both the U.K. and U.S. samples. The haplotype is not distinguished by any protein-coding polymorphisms, and, therefore, the functional variation may relate to gene expression. The QTL influences a broad range of reading-related cognitive abilities but has no significant impact on general cognitive performance in these samples. In addition, the QTL effect may be largely limited to the severe range of reading disability.  相似文献   

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