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Increasing knowledge of the biodiversity of parasitic copepods in the Argentinean Sea will provide a baseline against which changes in the distribution of marine biota can be detected. We provide new information on the distribution of 13 known species of parasitic copepods gathered from 11 species of marine fishes from Argentinean Sea, including 7 new host records and 9 new locality records. These species are: Bomolochus globiceps (Vervoort et Ramírez, 1968) and Nothobomolochus cresseyi Timi et Sardella, 1997 (Bomolochidae Sumpf, 1871); Brasilochondria riograndensis Thatcher et Pereira, 2004 (Chondracanthidae Milne Edwards, 1840); Taeniacanthus lagocephali Pearse, 1952 (Taeniacanthidae Wilson, 1911); Caligus rogercresseyi Boxshall et Bravo, 2000 and Metacaligus uruguayensis (Thomsen, 1949) (Caligidae Burmeister, 1835); Hatschekia conifera Yamaguti, 1939 (Hatschekiidae Kabata, 1979); Clavellotis pagri (Kr?yer, 1863), Clavella adunca (Str?m, 1762), Clavella bowmani Kabata, 1963 and Parabrachiella amphipacifica Ho, 1982 (Lernaeopodidae Milne Edwards, 1840), and Lernanthropus leidyi Wilson, 1922 and Lernanthropus caudatus Wilson, 1922 (Lernanthropidae Kabata, 1979). A list of host species lacking parasitic copepods, for which large samples were investigated by the authors, is also provided in order to compare in future surveys.  相似文献   
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A new species of Colobomatus Hesse, 1873 is described from pores of the cephalic sensory system and nostrils of Argentine goatfish, Mullus argentinae Hubbs et Marini, 1933 (Perciformes: Mullidae), living along the southwestern Atlantic coast. The fish were collected at different latitudes, stretching from the State of Rio de Janeiro in the north, through Santa Catarina, Rio Grande do Sul (Brazil) to of Mar del Plata (Argentina) in the south. The prevalence of the infection ranged from 42% through 84%. The new species look alike to two other species, parasites of mullids (C. steenstrupi and C. mulli) particularly in the body shape and the number, shape, and ornamentation of cephalic, thoracic, and genital processes. The new species, however, can be readily distinguished by having the central cephalic process shorter than lateral ones, the later being bilobed at tip forked, and a relatively larger abdomen. Furthermore, C. steenstrupi possesses relatively wider trunk processes with rounded tips, a short abdominal dorsal process, and attains a larger size (up to 3.6 mm). C. mulli also differs by having all body processes with forked tips, and relatively shorter sixth thoracic somite and abdominal segments 1-3. This is the third record of a species of Colobomatus in South American Atlantic waters.  相似文献   
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Background   Recent studies have demonstrated that individuals with Down syndrome (DS) present both central and verbal working memory deficits compared with controls matched for mental age, whereas evidence on visuospatial working memory (VSWM) has remained ambiguous. The present paper uses a battery of VSWM tasks to test the hypothesis that individuals with DS can also encounter specific difficulties in VSWM.
Method   Four tasks were administered to 34 children and adolescents with DS and 34 controls matched for verbal mental age. In two of these tasks, participants had to remember a series of locations sequentially presented on a matrix (spatial-sequential WM); in another two, they had to remember locations simultaneously presented (spatial-simultaneous WM).
Results and Conclusions   Results showed that individuals with DS are poorer than controls in the spatial-simultaneous tasks, but not in the spatial-sequential tasks. These findings were not due to a difference in speed of visuospatial processing. In fact, when performances of the two groups in VSWM were compared using speed measures as covariates, differences between groups remained. It is suggested that the simultaneous VSWM deficit of individuals with DS could be due to the request for processing more than one item at a time.  相似文献   
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The motility of the Fallopian tube plays an important role in the gametes and embryo transport. Disorders of the tubal motor function may be involved in a great number of patients with unexplained infertility. The aim of this study was to develop a method to measure the tubal motility by means of an hysteroscopic approach in humans. The following motor parameters were evaluated: 1) the basal pressure of each 1 cm tract of the tube; 2) amplitude and frequency of the tubal contractions; 3) the uterine intraluminal pressure eight patients in the follicular phase (FP group) and 8 in the luteal phase (LP group) of the menstrual cycle, were studied. The duration of the motility recording session was 12 +/- 3 minutes (range 7-19 minutes). No significant differences were shown between the two groups of patients, and no differences were found between the recordings obtained from the right and the left tubes.  相似文献   
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The immunoperoxidase method for involucrin detection was applied to the study of the maturation of epithelial lesions of the oral mucosa that included specimens of leukoplakia, lichen planus, verrucous carcinoma, carcinoma in situ and invasive carcinoma. Areas of orthokeratinized, parakeratinized, and non-keratinized normal mucosa were also studied. Normal orthokeratinized epithelia showed intracytoplasmic or pericellular staining in the suprabasal epithelial layers in a pattern similar to that of the normal epidermis. Parakeratinized and non-keratinized epithelia were less stained. Intense staining was observed in leukoplakia, whereas the staining of lichen planus was less intense but exhibited a more homogeneous pericellular staining pattern than leukoplakia. Verrucous carcinoma was markedly and very irregularly stained. Carcinomas in situ and invasive carcinoma exhibited a slightly positive and patchy reaction. The distribution patterns of involucrin in the lesions correlated very well with the degree of epithelial differentiation. In addition, irregular patchy distribution correlated with the degree of atypia, and was especially evident in carcinomas.  相似文献   
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