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1.
The chaetotaxy of Codonocephalus urniger (Rudolphi, 1819) cercariae recovered from Lymnaea palustris in a brackish water lake in Bulgaria is described and figured. Comparisons with Diplostomum spathaceum (Rudolphi, 1819) and D. pseudospathaceum Niewiadomska, 1984 cercariae indicate a similar general pattern in the distribution of sensilla but with marked differences in their number and arrangement on the ventral sucker, tail stem and furcae. Data on the chaetotaxy of other diplostomid species are used to reveal the similarities and variations in some complexes within the members of Diplostomidae with known cercarial chaetotaxy.  相似文献   
2.
Red (Trifolium pratense L., cv. “Start”) and white clover varieties (Trifolium repens L., cv. “Debut” and cv. “Haifa”) were waterlogged for 14 days and subsequently recovered for the period of 21 days. Physiological and biochemical responses of the clover varieties were distinctive, which suggested different sensitivity toward flooding. The comparative study of morphological and biochemical parameters such as stem length, leaflet area, dry weight, protein content, protein pattern and proteolytic degradation revealed prominent changes under waterlogging conditions. Protease activity in the stressed plants increased significantly, especially in red clover cv. “Start”, which exhibited eightfold higher azocaseinolytic activity compared to the control. Changes in the protein profiles were detected by SDS-PAGE electrophoresis. The specific response of some proteins (Rubisco, Rubisco-binding protein, Rubisco activase, ClpA and ClpP protease subunits) toward the applied stress was assessed by immunoblotting. The results characterized the red clover cultivar “Start” as the most sensitive toward waterlogging, expressing reduced levels of Rubisco large and small subunits, high content of ClpP protease subunits and increased activity of protease isoforms.  相似文献   
3.
The type-species of Singhia and Caballerotrema (Digenea: Echinostomatidae), parasites of freshwater fishes which have previously been assigned to the subfamily Singhiinae Yamaguti, 1958, are redescribed. One of the specimens of the type-series of Caballerotrema brasiliense Prudhoe, 1960 was identified as C. aruanense Thatcher, 1980. C. arapaimense Thatcher, 1980 is considered a species inquirenda. Himasthla piscicola Stunkard, 1960 is transferred to Caballerotrema as C. piscicola n. comb. The generic diagnoses of Singhia and Caballerotrema are redefined and Singhia is re-allocated to the Echinostomatinae Looss, 1899, the Singhiinae becoming a synonym of the latter.  相似文献   
4.
Re-examination of the type and newly collected material of Episthmium bursicola (Creplin, 1837) revealed the presence of a uroproct. The species is redescribed and transferred to the genus Uroproctepisthmium as U. bursicola n. comb. E. proximum Travassos, 1922 is also transferred to Uroproctepisthmium as U. proximum n. comb. The generic diagnosis of Uroproctepisthmium is redefined and Episthmium is tentatively retained as a synonym of Echinochasmus, following Odhner (1910), until a thorough revision of its constituent species is made.  相似文献   
5.
Fish allergy is associated with moderate to severe IgE-mediated reactions to the calcium binding parvalbumins present in fish muscle. Allergy to multiple fish species is caused by parvalbumin-specific cross-reactive IgE recognizing conserved epitopes. In this study, we aimed to produce cross-reactive single chain variable fragment (scFv) antibodies for the detection of parvalbumins in fish extracts and the identification of IgE epitopes. Parvalbumin-specific phage clones were isolated from the human ETH-2 phage display library by three rounds of biopanning either against cod parvalbumin or by sequential biopanning against cod (Gad m 1), carp (Cyp c 1) and rainbow trout (Onc m 1) parvalbumins. While biopanning against Gad m 1 resulted in the selection of clones specific exclusively for Gad m 1, the second approach resulted in the selection of clones cross-reacting with all three parvalbumins. Two clones, scFv-gco9 recognizing all three parvalbumins, and scFv-goo8 recognizing only Gad m 1 were expressed in the E. coli non-suppressor strain HB2151 and purified from the periplasm. scFv-gco9 showed highly selective binding to parvalbumins in processed fish products such as breaded cod sticks, fried carp and smoked trout in Western blots. In addition, the scFv-gco9-AP produced as alkaline phosphatase fusion protein, allowed a single-step detection of the parvalbumins. In competitive ELISA, scFv-gco9 was able to inhibit binding of IgE from fish allergic patients’ sera to all three β-parvalbumins by up to 80%, whereas inhibition by scFv-goo8 was up to 20%. 1H/15N HSQC NMR analysis of the rGad m 1:scFv-gco9 complex showed participation of amino acid residues conserved among these three parvalbumins explaining their cross-reactivity on a molecular level. In this study, we have demonstrated an approach for the selection of cross-reactive parvalbumin-specific antibodies that can be used for allergen detection and for mapping of conserved epitopes.  相似文献   
6.
Petasiger islandicus n. sp. is described and figured from a demographically isolated population of the horned grebe Podiceps auritus auritus (L.) in Lake Myvatn (Iceland). This new species belongs to the group of species with 19 collar spines which possess a large elongate-oval cirrus-sac, well-developed pars prostatica and massive bulb-like cirrus. Within this group, P. islandicus appears most similar to P. oschmarini Kostadinova & Gibson, 1998, a form with similar body dimensions described from the same host, but differs in having a larger head collar, collar spines, oral sucker, pharynx, testes and sucker-width ratio, and a smaller cirrus-sac, cirrus and eggs. Two Nearctic species resemble P. islandicus in general morphology but differ as follows: P. pseudoneocomense Bravo-Hollis, 1969 has a larger body and collar width, notably shorter collar spines, smaller testes and sucker-width ratio, and a shorter but much wider cirrus-sac which is also smaller relative to the ventral sucker and almost entirely anterior to it; and P. caribbensis Nassi, 1980 has a smaller body, shorter collar spines and a seminal vesicle which is small in relation to the cirrus-sac, vitelline fields reaching anteriorly to the level of the genital pore and the intestinal bifurcation is located more anteriorly.  相似文献   
7.
Four species of digeneans parasitic in the bogue Boops boops from the Spanish coast of the NE Atlantic are described. All are new records for this host, but one species is new and the other three are considered to be accidental parasites. Wardula bartolii n. sp. (Mesometridae) is distinguished from its two congeners on the basis of a range of morphometrical features, such as the post-ovarian extent of the uterus, the relative length of the attachment organ, the position of the pharynx and vitelline fields, and the absence of anterior caecal diverticula. The other three species are Lecithaster confusus Odhner, 1905, Aponurus laguncula Looss, 1907 (Lecithasteridae) and Accacladium serpentulum Odhner, 1928) (Accacoeliidae).  相似文献   
8.
A new species in the little-known digenean fauna of Paraguayan birds is described in detail, especially in relation to its terminal genitalia. The new form, Megalophallus deblocki n. sp., is a microphallid from the intestine of the snail kite Rostrhamus sociabilis (Vieillot). It is differentiated in detail from its congeners, but differs mainly in having a substantially larger phallus (e.g. in relation to the ventral sucker), a smaller ventral sucker and smaller eggs. Comments are included on the functional morphology of the terminal genitalia.  相似文献   
9.
Five species of digeneans parasitic in the pilchard Sardina pilchardus (Walbaum), a little studied host, from off the Algerian coast of the western Mediterranean are redescribed. These are Parahemiurus merus (Linton, 1910) Manter, 1940, Aphanurus stossichii (Monticelli, 1891) Looss, 1907, Aphanurus virgula Looss, 1907, Lecithaster confusus Odhner, 1905 and Pronoprymna ventricosa (Rudolphi, 1819) Poche, 1926. One of these, A. virgula, is a new record for this host. One other digenean, Hemiurus luehei Odhner, 1905, was also recorded from this host. A complete checklist of the helminth parasites of S. pilchardus throughout its distributional range, comprising 104 host-parasite records of 39 taxa, is presented.  相似文献   
10.
Patagifer Dietz, 1909 is revised and a key to the species is presented. P. oweni n. sp. is described from Threskiornis molucca (Cuvier) in the Western Province of Papua New Guinea and distinguished from the related P. chandrapuri Srivastava, 1952 by: the shape of the pair of large angle spines (cudgel-shaped vs sub-rectangular); pointed (vs rod-shaped) marginal spines; a smaller body and internal organs; more anteriorly located testes; and larger eggs. The new species differs from P. brygooi Richard, 1964 in its larger body, head collar, suckers, pharynx and eggs, longer oesophagus and testes, the latter being also more elongate and more anteriorly located, and a different number of collar spines (61-62 vs 59). P. bilobus (Rudolphi, 1819) (the type-species), P. parvispinosus Yamaguti, 1933, P. chandrapuri and P. vioscai Lumsden, 1962 are redescribed on the basis of museum and newly collected material. The variations in the number and size of the collar spines and other metrical characters of P. bilobus are studied in two different host species from Europe, Plegadis falcinellus and Platalea leucorodia. Other species considered valid are: Patagifer consimilis Dietz, 1909, P. acuminatus Johnston, 1917, P. fraternus Johnston, 1917, P. wesleyi Verma, 1936, P. brygooi and P. toki Onda, Imai & Ishii, 1983. P. plegadisi Sakla, Monib & Mandour, 1988 and P. simarai Nigam, 1944 are considered synonyms of P. bilobus, and P. sarai Saksena, 1957 is placed in synonymy with P. chandrapuri. Forms considered dubious are: P. bilobus of Machida et al. (Jpn J Parasitol 15:339, 1966) and Machida (Bull Natl Sci Mus Tokyo 11:157-160, 1968), P. simerai [sic] of Mehra (The fauna of India and adjacent countries. Platyhelminthes, 1980), P. skrjabini Hilmy, 1949 sp. inq. and P. srivastavai Peter, 1954 sp. inq. Lists of the records and hosts of the 11 valid species are included.  相似文献   
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