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151.
Specimens of the marine tanaid crustacea Halmyrapseudes spaansi, sampled in temporary littoral muddy patches near the mouth of the Kaw river (French Guiana, SE America), showed protozoan epibionts herein described as a new species: Cothurnia guyanensis sp. n. (Ciliophora, Peritrichia). These ciliates were covered by a cylindrical or bell-shaped lorica containing an oval elongated zooid with a rounded contractile vacuole located anteriorly in lateral position. The macronucleus was “S” shaped. The peristomial disk was anterior and included a polikinety and a haplokinety. The external stalk was short and broad, with 8–18 longitudinal conspicuous striations. Between the external stalk and the zooid, there were an endostyle and an mesostyle both short and broad. The striations of the external stalk were prolonged in the mesostyle. Telotroch stages were observed and described, as well as specimens with two zooids per lorica. Epibionts located on the ventral area, pereopods and antennae of the basibiont.  相似文献   
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Crabs of the species Liocarcinus depurator and Pilumnus hirtellus, collected on the west coast of Scotland, showed hydrozoan and protozoan epibionts. The epibionts of Liocarcinus depurator were the protozoan Ephelota plana and the hydrozoans Clytia gracilis and Leuckartiara sp. The epibionts of Pilumnus hirtellus were the protozoans E. plana and Zoothamnium sp. For Liocarcinus depurator the number of Ephelota per crab fluctuated between 0 and 47 and the greatest number of suctorians were located on the chelipeds, carapace and anterior pereiopods. The hydrozoans, for Liocarcinus depurator, showed densities of 0-20 (Clytia gracilis on the second pereiopod) and 0-507 individuals per crab (Leuckartiara sp., principally on chelipeds, carapace and the fourth right pereiopod). For Pilumnus hirtellus, Ephelota plana showed densities between 3 and 56 individuals per crab, the greatest number of suctorians being located on the same areas as on Liocarcinus depurator. There was a density of 10-69 individuals per crab of Zoothamnium sp. on Pilumnus hirtellus (located on the carapace). Ephelota plana has not been observed previously as an epibiont on crustacea, nor had Zoothamnium sp. as an epibiont on Pilumnus hirtellus. Both hydrozoans, Leukartiara and Clytia, have not been previously described as epibionts on Liocarcinus depurator. Data about the morphological characteristics and distribution of these epibionts are included.  相似文献   
155.
Gregorio Oclander 《CMAJ》1966,94(5):218-222
Sequential oral contraceptive therapy was devised to inhibit ovulation by a potent estrogen alone. A progestational agent was added at the end of the course of therapy to prepare the endometrium for adequate withdrawal bleeding. The program consisted of giving 80 μg. of metranol daily for 15 days and then a combination of 80 μg. of mestranol and 2 mg. of chlormadinone acetate for five additional days. Such a regimen proved to be effective in 6070 patients carefully observed for 82,085 cycles of therapy at 25 medical centres.Increased cycle regularity was noted: 98.1% of the cycles were 25 to 31 days long. In 80.1% of cycles, the withdrawal interval was two to five days in length. Duration of flow was four to six days in 85.3% of the therapeutic cycles. The amount of flow decreased as compared with pretreatment values. The incidence and severity of dysmenorrhea during sequential therapy were significantly lower than before treatment. Side effects, usually infrequent, diminished as therapy was continued; the average incidence of breakthrough bleeding was 1.9% and nausea was 2.9%. Extensive laboratory studies showed no consistent abnormalities. For oral contraception, sequential therapy has proved to be virtually 100% effective when taken as directed.  相似文献   
156.
Canine parvovirus (CPV), a fast-evolving single-stranded DNA virus, comprises three antigenic variants (2a, 2b, and 2c) with different frequencies and genetic variability among countries. The contribution of co-infection and recombination to the genetic variability of CPV is far from being fully elucidated. Here we took advantage of a natural CPV population, recently formed by the convergence of divergent CPV-2c and CPV-2a strains, to study co-infection and recombination. Complete sequences of the viral coding region of CPV-2a and CPV-2c strains from 40 samples were generated and analyzed using phylogenetic tools. Two samples showed co-infection and were further analyzed by deep sequencing. The sequence profile of one of the samples revealed the presence of CPV-2c and CPV-2a strains that differed at 29 nucleotides. The other sample included a minor CPV-2a strain (13.3% of the viral population) and a major recombinant strain (86.7%). The recombinant strain arose from inter-genotypic recombination between CPV-2c and CPV-2a strains within the VP1/VP2 gene boundary. Our findings highlight the importance of deep-sequencing analysis to provide a better understanding of CPV molecular diversity.  相似文献   
157.
The authors tested the influence of gentamicin, spectinomycin dihydrostreptomycin on the ADP and epinephrine in vitro induced platelet aggregation. Our aim was to demonstrate if platelet aggregation in vitro had some influences by antibiotics. A reduction in platelet aggregability, strictly dependent from the used antibiotic dose was observed. We have studied platelet function thanks to Born's method, adding to PRP gradual therapeutics doses of antibiotics. The results showed a reduction of platelet function which was dose-depended, and, particularly, gentamicin seemed to be the most effective among aminoglycosides. An interference between these drugs and the ADP and epinephrine binding to specific platelet receptor sites is proposed.  相似文献   
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Biguanides inhibit d-glucose uptake in vesicles from small-intestinal brush border membranes. Evidence is presented that this inhibition is due to a reduced concentration of Na+ in the microenvironment of the carrier(s) for d-glucose. Biguanides do not inhibit the uptake of either d-fructose or l-glucose.  相似文献   
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