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1.
Summary

In the amphipod crustacea Orchestia gammarellus (heterogametic species: 2AXY male, 2AXX female), two kinds of sex ratio bias are recorded, hi the first category (thelygeny linked with intersexuality) a parasitic protozoa modifies the sexual phenotype of genetic males and can transform them into intersex males or functional females. This leads to the occurrence of viable 2AYY males and females.

In a second kind of sex ratio bias, males cause hereditary shifts of sex ratio. These ‘paternal sex ratio’ (psr) traits are transmitted by the male at each generation. Psr-f males cause an excess of females, psr-m males an excess of males.

The psr-m trait has a strictly patroclinous mode of transmission, but females from psr-f strains intervene in the expression of psr-f trait. Intra-sib matings are characterized by an excess of males. This characteristic seems to be linked with the age of the female. It disappears during successive brood. A relation between the psr-m and psr-f trait is observed: some psr- m males give psr-f males in the their progeny.

The analysis of crosses between psr-f or psr-m males and YY females allows to discard meiotic drive or sex lethal mortality as causes for the psr traits. Our results are best explained if we suppose that psr-f and psr-m males are XX and that extrachromosomal hereditary factors or transposable genetic elements intervene in the determinism of the psr traits: a psr-m factor able to masculinize all the embryos and a psr-f factor able to masculinize embryos if present in a sufficient amount.  相似文献   

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Zearalenone (F-2 toxin) an estrogenic mycotoxin secreted by some species ofFusarium exhibits an antibacterial activity which can be easily demonstrated in Gram-positive spore forming bacteria, especially inBacillus sp.Morphologically abnormal cells were produced byBacillus thuringiensis (Berliner) in response to zearalenone. The most significant ultrastructural alterations obtained with the mycotoxin at 2.5 or 5.0 g/ml, are: increase of number of mesosomes which are hypertrophied, decrease of ribosomes, formation of imperfect cell septa and unknown crystalloid inclusion.These effects which provoke induction of atypical long cells, resemble those obtained with one other mycotoxin which possesses as zearalenone an unsaturated lactone structure: aflatoxin B1.  相似文献   

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Elderly patients are commonly frail, due to a lot of comorbid conditions and numerous medications. These patients are at high risk of bleeding when treated with vitamin K antagonist (VKA). Special considerations on the choice of VKA drug, dosing and monitoring have to be taken into account in the elderly in order to avoid over-anticoagulation and to minimize the haemorrhagic risk which consequences may be dramatic or fatal in this age group. In these patients, INR monitoring is crucial, especially at the start of treatment. The use of dosing algorithms specifically developed for elderly patients allows to decrease over-anticoagulation during the initiation period. INR has to be monitored more frequently in case of acute illness or in case of modification of the associated drugs. Patient education is of great importance, even in geriatric patients and has been shown to improve the quality of anticoagulation. New oral anticoagulants with a wider therapeutic index seem to be of great interest.  相似文献   

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C. Guillemin 《Genetica》1985,67(3):193-200
Analysis of metaphasic meiotic karyotypes in male of Pleurode les waltlii(Amphibia, Urodela) after silver ammoniacal staining of chromosomes. In the newtPleurodeles waltlii, the ammoniacal silver staining technique was applied to the male meiotic chromosomes at metaphase I and II. A specific staining of paracentromeric heterochromatin and of the centromere is observed on each chromosome of the complements. The two karyotypes are analysed and the homology between meiotic and mitotic chromosomes is established.
Analyse des caryotypes métaphasiques méiotiques chez le male dePleurodeles waltlii (Amphibien, Urodèle) après coloration des chromosomes par l'argent ammoniacal
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Résumé Par un jeûne de trois jours ou par l'administration per os de réserpine(2 à 4 mg/kg) durant 15 à 24 jours, on a provoqué des ulcères d'estomac chez des rats. Une partie des bÊtes ainsi traitées fut exposée durant cette période et pendant 2 heures par jour à un air ionisé contenant 5.000 à 15.000 petits ions par cm3 d'air. Pour les animaux soumis au jeûne, la proportion d'ulcères se monte à 93% chez les bÊtes de contrÔle, alors qu'elle n'est que de 59% chez les bÊtes traÎtées par l'air ionisé. Pour les rats traÎtés à la réserpine, les proportions sont de 83,respectivement de 45%. On a en outre exposé 66 patients atteints d'ulcères d'estomac et d'intestins durant 12 à 15 jours et pendant 15 à 45 minutes par jour à un air contenant 5.000 à 10.000 petits ions négatifs par cm3 d'air. Pour 38 d'entre eux, la douleur et les autres symptÔmes avaient diminué ou disparu après le traitement.
Gastric ulcers were produced in rats by starvation for 3 days or the administration of reserpine (2 to 4 mg/kg) for 15 to 24 days. Some of the animals were exposed to ionized air for 2 hours daily during these periods(5,000 to 15,000 small negative ions/m3 air). The incidence of ulcer development was 93% in the untreated starved rats and 59% in those treated with ionized air; 83% in the animals treated with reserpine and 45% in those with additional ionized air treatment. In a clinical investigation 66 patients with peptic ulcer were exposed for 12 to 15 days to 5,000 to 10,000 small negative ions/m3 air daily. Pain and other symptoms were diminished or abolished after this treatment in 38 patients.

Zusammenfassung Bei Ratten wurden durch 3 Tage Hungern oder Behandlung mit Reserpin (2–4 mg/kg) wÄhrend 15 bis 24 Tagen Magenulcera provoziert. Ein Teil der Tiere wurde wÄhrend dieser Perioden 2 Std. tÄglich ionisierter Luft exponiert (5.000–15.000 kleine Ionen/m3 Luft). Die Ulcusrate betrug bei den unbehandelten Hungertieren 93%, bei den mit ionisierter Luft behandelten 59%; bei den Reserpin behandelten Tieren betrug sie 83% und bei den zusÄtzlich mit ionisierter Luft behandelten 45%. In der Klinik wurden 66 Patienten mit Magen-Darmulcera 12–15 Tage lang 15–45 min tÄglich mit 5.000 –10.000 neg. kleinen Ionen/m3 Luft behandelt. In 38 Patienten waren nach der Behandlung der Schmerz und die anderen Symptome abgeschwÄcht oder verschwunden.
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G. Lucotte 《Human genetics》1980,54(1):97-102
Summary The electrophoretic mobilities of serum enzymes and other proteins were investigated at 35 loci in 25 unrelated individuals of the chimpanzee Pan troglodytes. In this population the mean average of individual polymorphism is =0181, and the average level of heterozygoty =0.022. The same pattern of individual variability is found in Pan troglodytes and Homo sapiens.  相似文献   

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After we had supposed that there could be a relation between the ability of some Caryophyllaceae (tribes of Diantheae and Lychnideae) to synthetize two series of very particular carbohydrates (lychnose and isolychnose) and the ability of thePhialophora cinerescens to infect members of these two tribes, we have looked for the constituents of soluble and cell wall carbohydrates:
  • in carnations of different ages and different cultivars; only the old carnations contain polyoses of the lychnose and isolychnose series, whereas the young carnations are already susceptible to the parasite;
  • n healthy and diseased Sim carnations, Lolita and New Red Sim; these two cultivars offer a difference of susceptibility to the disease and, parallely a difference of their amount in hemicellulose; great disparities appear between healthy and diseased carnations as regards their composition in soluble and cell wall carbohydrates.
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    ObjectivesCT-coronary angiography (CTCA) and myocardial perfusion scintigraphy (MPS) have both high negative predictive values in detecting coronary artery disease (CAD) but suboptimal predictive positive values, leading to unnecessary invasive coronary angiography (ICA) in case of equivocal findings. Combining these two tests may obviate their inherent limitations.Patients and methodsSixty-seven patients at mostly intermediate risk of CAD were subjected to either CTCA (45 patients) or MPS (22 patients) at first test, followed by the second test because of equivocal results of the first test. A discordant defect between the two tests was considered as false positive, hence likely to exclude CAD, and a concordant defect as true positive, likely to confirm CAD. All patients with concordant defects were referred to subsequent ICA. All patients with discordant defects (except for seven of them who underwent ICA too) were subjected to a mean follow-up of 730 ± 377 days.ResultsDiscordant findings between CTCA and MPS were found in 41 patients, from whose 7/7 had no significant stenosis at the invasive angiography and 34/34 had no major cardiac event during follow-up. Concordant findings were found in 26 patients. Invasive coronary angiography revealed significant stenoses in 14/26 patients; 9/14 of them needed revascularization.ConclusionA strategy combining CTCA and MPS may safely reduce referral to ICA in patients with equivocal findings at a single examination.  相似文献   

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