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1.
Three gonad-infecting species of Philometra Costa, 1845 were, for the first time, recorded from perciform fishes from estuarine and marine waters in South Carolina and Georgia, USA: Philometra charlestonensis sp. nov. from the scamp Mycteroperca phenax (Jordan et Swain) (Serranidae), P. saltatrix Ramachandran, 1973 from the bluefish Pomatomus saltatrix (Linnaeus) (Pomatomidae), and Philometra sp. from the Atlantic croaker Micropogonias undulatus (Linnaeus) (Sciaenidae). The new species is characterized mainly by males (body length 2.65–3.14 mm) with equally long, needle-like spicules (length 132–141 μm) and the gubernaculum (81–93 μm) bearing dorsal transverse lamella-like structures on its distal portion, the body length of gravid females (168–247 mm), the presence of a well-developed anterior bulbous inflation on the female oesophagus, and by the length of the first-stage larvae (544–597 μm). A key to gonad-infecting species of Philometra parasitizing marine and brackish-water fishes is provided.  相似文献   

2.
The tissues of herbivores are commonly infected with cysts of parasites belonging to the apicomplexan genus Sarcocystis, but such sarcocysts are rare in bears. Here, we describe a new species, Sarcocystis arctosi, based on the mature sarcocysts identified in two brown bears (Ursus arctos) from Alaska, USA. Microscopic sarcocysts (37–75 × 20–42 μm) had thin walls (<1 μm). The outer layer of the sarcocyst, the parasitophorous vacuolar membrane (pvm), was wavy in outline and had minute undulations that did not invaginate towards the sarcocyst interior; these undulations occurred at irregular intervals and measured up to 100 nm in length and up to 60 nm width. The ground substance layer beneath the pvm was smooth and lacked microtubules. Longitudinally cut bradyzoites measured 5.6–6.8 × 0.7–1.8 μm. A major portion of nuclear small subunit rDNA sequence obtained from these sarcocysts was similar to that previously obtained from the hepatic schizonts of a S. canis-like parasite from polar bears (Ursus maritimus).  相似文献   

3.
Examination of 98 gold skink, Eumeces schneiderii Daudin, 1802 from Alexandria and Marsa-matroh Governorates, Egypt revealed oocysts of Choleoeimeria baltrocki (Daszak et Ball, 1991) n. comb. in the gall bladder and faeces. The prevalence of the infection was 40.8%. Sporulated oocysts were found in the faeces and the gall bladder contents. Sporulated oocysts were tetrasporocystic, cylindrical, reaching a mean of 38.7 (36–42) × 19.9 (17–25) μm with bilayered smooth and colourless wall. The dizoic sporocysts were subspherical and measuring 10.8 (9.5–13) × 9.3 (8–10.5) μm with a large globular sporocyst residuum. Sporocyst wall was bilayered joined by meridional suture. Sporozoites were crescent-shaped, blunt at one end and slightly tapered at the other. Endogenous stages (meronts, gamonts, gametes and young oocysts) were confined to the gall bladder epithelium and the infected cells were hypertrophied. Based on the morphological features of the exogenous stages and endogenous development of the present parasite, its generic affiliation was revised and placed into the genus Choleoeimeria.  相似文献   

4.
A species of Sarcocystis is reported from a naturally infected African grey parrot, Psittacus erithacus, from Costa Rica. Only mature sarcocysts, measuring up to 2 mm in length and up to 750 μm in width, were observed. The sarcocyst wall was smooth. The villar protrusions on the sarcocyst wall were up to 5 μm long and up to 1.1 μm wide; they were folded over the sarcocyst wall giving a thin-walled appearance. The microtubules in villar protrusions were smooth and confined to villar protrusions. Bradyzoites in sections were 5.4–6.6 × 1.3–2.0 μm in size. Sequencing the small subunit and first internal transcribed spacer portions of ribosomal DNA related this parasite to, but distinguished it from, previously characterized species of Sarcocystis that encyst in the musculature of birds and complete their sexual development in New World opossums of the genus Didelphis. This evidence suggests that the parrot may have acquired its infection from an opossum from which it suffered a debilitating attack a year prior to the onset of depression, anorexia, and ultimately death.  相似文献   

5.
6.
Thelandros vietnamensis sp. nov. (Oxyuroidea, Pharyngodonidae) from the intestines of an agamid lizard, Leiolepis reevesi, collected in Vietnam is described and illustrated. Thelandros vietnamensis represents the 3rd Oriental species to be described and is distinguished from all other species by length of spicule (485–536 μm) of the male; all other species have spicules less than 200 μm.  相似文献   

7.
A species of Sarcocystis is reported from two naturally infected Buffon’s macaws (Ara ambigua) from Costa Rica. Only mature sarcocysts, measuring up to 950 μm in length and up to 75 μm in width, were observed. By light microscopy the sarcocyst wall was thin (< 1 μm thick) and smooth. The villar protrusions on the sarcocyst wall were up to 4.0 μm long and up to 0.6 μm wide; they were folded over the sarcocyst wall giving a thin-walled appearance. The microtubules in villar protrusions were smooth and confined to villar protrusions. Bradyzoites in sections were 4.0–5.9 × 0.8–1.8 μm in size. Structurally, sarcocysts from the macaw appeared different from sarcocysts of other avian species. This is the first report of Sarcocystis infection in this host.  相似文献   

8.
Heligmosomoides vandegrifti sp. nov. (Nematoda, Heligmosomidae) is described from Peromyscus maniculatus (Rodentia, Cricetidae) from Pennsylvania, USA. It differs from its closest congener, H. douglasi, in the number of cuticular ridges (35 vs. 32 in male, 36 vs. 41 in female at mid-body), longer bursal rays 2 in relation to rays 3, and in having smaller spicules (635–740 μm long vs. 1 mm). It is proposed that both H. douglasi and H. vandegrifti sp. nov. are parasites of capture from species in North American arvicoline rodents.  相似文献   

9.
Three new coccidian (Apicomplexa, Eimeriidae) species from the sayaca tanager, Thraupis sayaca, from Brazil, are reported in the current study. Isospora sanhaci sp. nov. oocysts are spherical to subspherical, 22.1 × 21.0 μm, with smooth, bilayered wall, ∼1.0 μm. Micropyle, oocyst residuum and polar granule are absent, while Stieda and substieda bodies are present. Sporocysts are elongated, 17.0 × 9.9 μm. Sporocyst residuum is present, sporozoites have one refractile body and a nucleus. Isospora sayacae sp. nov. are spherical to subspherical, 28.9 × 27.4 μm, with smooth, bilayered wall, ∼1.3 μm. Micropyle, oocyst residuum and polar granule are absent, while Stieda and substieda bodies are present. Sporocysts are bottle-shaped, 23.4 × 11.8 μm and containing a sporocyst residuum and sporozoites with one refractile body and a nucleus. Isospora silvasouzai sp. nov. are spherical to subspherical, 25.5 × 22.6 μm, with a smooth, bilayered wall, ∼1.0 μm. Micropyle and oocyst residuum are absent, but one polar granule is present. Sporocysts are pyriform ellipsoidal, 17.6 × 10.5 μm. Stieda and substieda bodies and sporocyst residuum are present and sporozoites have one refractile body and a nucleus.  相似文献   

10.
Falcaustra desilvai sp. nov. (Ascaridida, Kathlaniidae) from the large intestine of Cnemaspis aff. tropidogaster (Squamata, Gekkonidae) is described and illustrated. Falcaustra desilvai represents the 4th nematode species from Sri Lanka to be assigned to the genus and is distinguished from other Sri Lankan species by the distribution pattern of caudal papillae (12 precloacal, 2 adcloacal, 10 postcloacal, and 1 median), length of spicules (956–1046 μm) and absence of a pseudosucker.  相似文献   

11.
12.
During the course of a study on the endohelminth parasites of birds, specimens of an undescribed species of Tylodelphys Diesing, 1850 (Diplostomidae) were collected from the wood stork, Mycteria americana L., from Formosa Province, Argentina. Tylodelphys brevis sp. nov. can be distinguished from the other Neotropical species of this genus, T. elongata, T. americana and T. adulta, principally by the smaller size of the body (570–851 μm), by the fewer eggs in the uterus (1–2) and by the smaller ratio of body to egg length (6–8). This is the second report of an adult of the genus Tylodelphys from Argentina and the first record of a digenean species parasitizing Mycteria americana in this country.  相似文献   

13.
Diplectanum parvus sp. nov. is described from the coral reef fish Cephalopholis urodeta collected off New Caledonia, South Pacific, and is the first diplectanid described from this fish. The new species has a very small male copulatory organ (24 μm in length) and a minute body (246 μm in length) and is close to D. nanus Justine, 2007 from which it can be distinguished by the shape of dorsal bars and various measurements. These species belong to a group of diplectanids found in groupers (Serranidae, Epinephelinae), characterised by small funnel-shaped male copulatory organs and no sclerotized female organs. The attribution of these parasites to Diplectanum Diesing is provisional. Other parasites are briefly listed.
Résumé   Diplectanum parvus sp. nov. est décrit du poisson de récif corallien Cephalopholis urodeta pLché en Nouvelle-Calédonie, et est le premier Diplectanidae décrit de ce poisson. La nouvelle espèce a une organe copulateur male (long de 24 μm) et un corps (long de 246 μm) très petits et est proche de D. nanus Justine, 2007 dont elle peut eêtre différenciée par la forme des barres dorsales et diverses mesures. Ces espèces appartiennent B un groupe de Diplectanidae parasites de mérous (Serranidae, Epinephelinae), caractérisés par des organes copulateurs males petits en forme d’entonnoir et l’absence d’organes sclérifiés femelles, qui sont attribués provisoirement B Diplectanum Diesing. Les autres parasites sont brièvement mentionnés.
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14.
Dolichorchis lacombeensis sp. nov., a digenean parasite of the gut of the cocoi heron, Ardea cocoi (L.), is described as a new species from Buenos Aires Province, Argentina. This new species most closely resembles D. buteii and D. tregenna in the distribution of the vitelline follicles, which reach the intestinal bifurcation in the forebody. D. buteii can be distinguished from D. lacombeensis sp. nov. by the distribution of the vitelline follicles in the hindbody, which are concentrated in midline, by the presence of a sphincter in genital pore and by the size of holdfast organ and posterior testis, which are larger, (240–400 × 176–240 and 315–464 × 240–410 μm, respectively). D. tregenna differ from the new species by their larger measurements (pseudosuckers’ length 90–100, pharynx 52–90 × 50–70 and eggs 89–104 × 48–68 μm).  相似文献   

15.
In thisin vitro study using a purified sarcolemmic fraction of guinea pig myocardium, the 13(S)-hydroperoxide of linoleic acid (13-HPODE) increased in a dose-dependent manner the permeability of myocardial sarcolemma to Ca ions in concentrations above 10 μmol/liter, stimulated Na/Ca exchange there in concentrations from 0.1 to 10 μmol/liter, and exerted a digitalis-like action on sarcolemmic Na,K-ATPase in concentrations between 0.1 and 100 μmol/liter (IC50=20 μmol/liter). The results indicate that the linoleic acid hydroperoxide may be an effective modulator of sarcolemmic Ca2+ transport and of membrane-bound enzymes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N o 9, pp. 255–257, September, 1995 Presented by D. F. Chebotarev, Member of the Russian Academy of Medical Sciences  相似文献   

16.
Falcaustra papuensis sp. nov. (Ascaridida, Kathlaniidae) from the large intestine of Sphenomorphus simus (Squamata, Sciencidae) is described and illustrated. Falcaustra papuensis represents the 4th Australo-Papuan species assigned to this genus and is distinguished from other Australo-Papuan species by the distribution pattern of caudal papillae (6 precloacal, 6 adcloacal, 8 postcloacal, and 1 median), length of spicules (561–714 μm) and presence of a pseudosucker. Sphenomorphus simus was found to harbor 2 additional species of nematodes, Meteterakis crombiei and Oswaldocruzia bakeri. Sphenomorphus simus represents a new host record for each of these nematode species.  相似文献   

17.
The effects of M1 and M2 cholinoceptors on stimulated water transport in the urinary bladder of the common frogRana temporaria L. are described. In the presence of pirenzepine, a selective M1 cholinoceptor antagonist, carbachol stimulated water transport. Activation of M2 cholinoceptors by oxotremorine in concentrations of 0.5–5.0 μM inhibited water transport, whereas their activation by this compound in higher concentrations (10–100 μM) stimulated it. The use of the phospholipase C inhibitor neomycin (0.5 mM) and the calmodulin inhibitor W-7 (1 mM) indicated that activation of M2 cholinoceptors switches on phospholipid-Ca2+-calmodulin-dependent mechanisms. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N o 9, pp. 252–254, September, 1995 (Presented by P. V. Sergeev, Member of the Russian Academy of Medical Sciences)  相似文献   

18.
The present study describes the ultrastructure of mature vitellocytes of the trypanorhynch cestode Progrillotia pastinacae Dollfus, 1946 (Progrillotiidae), a parasite of the common stingray Dasyatis pastinaca (Linnaeus, 1758) (Dasyatidae). The vitelline cells of this species measure about 24 μm in length and about 20 μm in width. They have small, elongated, slightly lobulated nuclei, about 4–5 μm in length, with large dense elongated nucleoli and numerous irregularly-shaped dense clumps of heterochromatin. The extensive cytoplasm is rich in numerous cell organelles and cell inclusions. While the perinuclear cytoplasm contains numerous long parallel cisternae of GER, ribo-and polyribosomes, several Golgi complexes and mitochondria, the peripheral cytoplasm contains predominantly three types of cell inclusions: a great number of large lipid droplets, several shell globule clusters, and a very small amount of glycogen-like particles. The most characteristic features of vitellocytes in P. pastinacae are having almost no traces of glycogen and the great number of large, highly osmiophobic lipid droplets representing saturated fatty acids. The presence of large amounts of lipids also in two other trypanorhynchs, Grillotia erinaceus (Beneden, 1858) Guiart, 1927 and Dollfusiella spinulifera (Beveridge et Jones, 2000) Beveridge, Neifar et Euzet, 2004, is in strong contrast to the condition in the most evolved cestodes, Cyclophyllidea, that usually show no trace of lipids.  相似文献   

19.
Six simple sequence repeat (SSR)-enriched genome libraries from Pythium aphanidermatum, P. irregulare, and P. cryptoirregulare were constructed to develop SSR markers. One hundred six SSR primer pairs for P. aphanidermatum, 73 for P. cryptoirregulare, and 82 for P. irregulare were initially identified. After examining primers, the most polymorphic and reproducible SSR markers were selected for each Pythium species; 14 in P. aphanidermatum, 21 in P. irregulare, and 22 in P. cryptoirregulare. Analysis of isolates from each Pythium species using SSR markers showed the high degree of gene diversity and polymorphic information content (PIC) value in the three species. The average number of alleles was 3.5–5.3 in the three Pythium species. Seven SSR loci from P. cryptoirregulare and P. irregualre showed the distinct genetic separations of P. irregualre complex isolates. SSR markers identified for the three Pythium target species were highly transferable to other closely related Pythium species. Cross-amplification was found in all SSR markers between P. cryptoirregulare and P. irregulare. SSR loci were successfully amplified by direct PCR from mycelia of P. aphanidermatum, P. cryptoirregulare, and P. irregulare. These newly developed SSR markers can be used for population genetic studies and monitoring the movement of isolates in crop production systems or in nature.  相似文献   

20.
The susceptibility of Na,K-ATPase from bovine brain to various compounds containing active oxygen radicals is assessed. Sodium nitroprusside slightly inhibits Na,K-ATPase, while light-induced NOo radicals (controlled by the rate of ascorbate oxidation) have no effect on the enzyme. When added in concentrations equally effective in the ascorbate oxidation assay, hydrogen peroxide and sodium hypochlorite inhibit Na,K-ATPase by 70 and 25–30%, respectively. The Fe-dinitrosyl-cysteine complex is the most potent (K0.5=20 μM) inhibitor of Na,K-ATPase. It is demonstrated that different free oxygen radicals accumulated in the ischemic brain cause different kinds of damage to Na,K-ATPase. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N o 3, pp. 275–278, March, 1996 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences  相似文献   

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