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1.
At least two members of the herpesviridae family, the human cytomegaloviruses (HCMV) and the herpes simplex viruses (HSV) can be found in human semen; but the role of the germ cells in the sexual transmission of these viruses is not clear. In teenagers and the adult population, sexual contact is considered to be a common mode of HCMV acquisition. HCMV was isolated from semen specimens of 33 % of HIV infected homosexual men, 20 % of HIV uninfected homosexual men and only of 2,4 % of healthy heterosexual men. Virus particles could be demonstrated by electron microscopy examination inside the sperm head as well as in the seminal liquid but at present, there is no direct evidence either for HCMV transmission via fertilization or for induction of fetal anomalies by vertical transmission. Transmission via donor semen is undoubtedly possible although not yet described and it may be safer to employ HCMV seronegative donor for all recipients, regardless of the recipient’s serologic status. The development of serologic assays that differentiate the two serotypes of HSV demonstrated the worldwide distribution of genital HSV-2 which has been increasing in many developed countries throughout the last two decades. In several studies, HSV-2 has been recovered from the male reproductive tract, specifically the prostate, seminal vesicles, vasa and testes, in the absence of active lesions. In contrast, tissue cultures of semen sampled during lesion-free periods had been uniformly negative for HSV. However recently, one report documents transmission of HSV-2 via therapeutic donor insemination and illustres the fact that semen might be a vehicle of transmission of HSV. At present, it is adequate to recommend that men, with a history of a recurrent genital herpes or who have a sexual partner with such a history, are excluded as potential semen donors. Further, in the near future, with the increase of asymptomatic viral shedding from the genital tract, the presence of HSV-2 antibody could be added as an exclusion criterion.  相似文献   

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H. Audemard 《BioControl》1987,32(1):59-71
Résumé La lutte biologique contre les organismes nuisibles aux vergers évolue par étape vers une Protection intégrée. Dans cette optique, les recherches se développent en France sur les points suivants: effets indésirables des pesticides sur l'entomofaune auxiliaire, r?le d'abri-refuge pour l'entomofaune autochtone joué par l'environnement végétal des vergers, diversification des procédés de lutte, mise au point de méthodes plus sélectives, sélection de variétés résistantes ou moins sensibles aux attaques de plusieurs organismes nuisibles, amélioration des méthodes de surveillance des vergers pour la prévision des risques de dégats, lutte raisonnée contre les maladies cryptogamiques. La mise au point de programmes de lutte intégrée dépend essentiellement des possibilités de lutte disponibles contre les ennemis-clés. Dans les vergers de pommiers et de poiriers fran?ais, les ennemis-clés appartiennent à groupes d'arthropodes: Carpocapse (Cydia pomonella L.), Tordeuses de la pelure, Aphides, Psylle du poirier (Psylla pyri L.) Acariens phytophages et aussi à trois maladies fongiques: Tavelure du pommier (Venturia inaequalis Cke.) Wint., O?dium du pommier (Podosphaera leucotricha Ell. et Ev.), Tavelure du poirier (Venturia pirina (Bref.) Aderh. Les méthodes de lutte sélective sont passées en revue: régulateurs de croissance des insectes, lutte biologique par lachers de parasites et de prédateurs insecticide microbiologique, lutte par confusion avec les phéromones sexuelles. L'application de certaines d'entre elles dépend des possibilités de production industrielles d'agents biologique ou biotechnique. Les principaux éléments ayant contribué à une application pratique des programmes de lutte raisonnée et de lutte intégrée ont été: l'amélioration des connaissances biologiques et de la nuisibilité des organismes phytophages, ainsi que des méthodes de surveillance et de prévision permettant l'utilisation des seuils de tolérance économique l'aménagement de la lutte chimique contre le Carpocapse en vergers de pommiers, la démonstration de la bonne efficacité des prédateurs du Psylle du poirier, spécialement desAnthocoris. La lutte raisonnée, appliquée sur plusieurs milliers d'hectares de vergers de pommiers et de poiriers en France, a permis de réduire de plus de 50% le nombre de traitements avec un bon niveau économique de protection. Dans les vergers d'abricotiers, les maladies parasitaires, principalement l'Enroulement chlorotique causé par un mycoplasme, représentent les problèmes les plus importants. Des essais sont en cours pour parvenir à une lutte raisonnée contre la Petite mineuse (Anarsia lineatella Zell.) et le puceronHyalopterus pruni Geoffr. qui est l'agent de dissémination de la Sharka (maladie due à un virus de type I.L.A.R.).   相似文献   

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Dr. W. F. Wassink 《Genetica》1935,17(1-2):103-144
Sans résumé  相似文献   

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D. Arsigny 《PSN》2008,6(4):205-214
This article aims to show that philosophy, particularly Epicureanism and Stoicism, had an essentially therapeutic role in antiquity — the various schools of philosophy dispensing specific teachings aimed at treating mental suffering, in a precise place (the scholé), with a master and a specified methodology. Of course, it may seem anachronistic to try and compare a modern, progressive and proven therapeutic method such as cognitive behavioural therapy (CBT, TCC in French) with a frequently dogmatic, 2000-year-old school of philosophy. And yet, the difference is not as clear-cut as we might think, since the two have much in common, such as similar kinds of suffering, a referent (or therapist), common methods (language, reasoning) and a common goal (peace of mind). We therefore intend to try and synthesise the meeting points and also the differences between two main schools of antique philosophy and CBT.  相似文献   

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Over the last fivty years, the risk factors for infertility have increased substantially, particularly those due to the environment. Spermatogenesis and spermatozoa can be affected by physical (ionizing radiation microwaves, heat, cryopreservation) or chemical agents (antimitotics drugs, antibiotics, tranquillizers, insecticides, pesticides, industrial solvants, some heavy metals, alcohol, cannabis etc.). Some natural factors, as stress or paternal age (ageing or very youthful age relatively to about thirty) also seems to affect spermatogenesis and, particularly, the age can be joined with the previous ones. On the whole, these factors are able to decrease the male fertility through some changes about the concentration, the motility or the morphology of spermatozoa and so it is possible to describe populations subject to the risk. Moreover, these spermatogenetic changes can lead abnormalities in progeny. For instance, some antimitotic drugs as cyclophosphamide, when administrated to the male rat, lead malformations or functional anomalies as behavioral troubles. The industrial solvents lead a decrease of the birth weight and the cannabis leads an increase of the ante-or post-natal death. Moreover, the change of the paternal spermatogenesis caused by cannabis can be found again in the male progeny. The problem is similar with the lead, the benzodiazepines and the alcohol. Concerning the physical factors, some authors have shown that the children born from radiation exposed fathers presented an increase of the probability of leukemia. In animal, the postimplantation loss is increased when the father is irradiated or subjected to heat before mating. Finally, the paternal ageing is responsible for new dominant autosomic mutations. Moreover, in animal and man, paternal ageing and, in man, very youthful age, also seems responsible for a gradual lowering in the level of progency cerebral functions. On the whole, these data should lead to an preventive attitude which would be more effective before about thirty years of age than after this period.  相似文献   

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Dans le cadre de la gestion des analyses urgentes de biologie, le site d’Argenteuil a mis en place une organisation originale (Filière “urgence” mise en place depuis avril 1998) assurant en particulier rapidité et sécurité dans la production des résultats. Nous avons recueilli le témoignage des acteurs principaux à l’origine de cette mise en place.  相似文献   

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J. Costentin 《PSN》2010,8(4):182-186
Caffeine, the main alkaloid in coffee, corresponds to the 1-3-7 trimethylxanthine. Its concentration is lower in tea and chocolate, where it is associated with theophylline, 1-3 dimethylxanthine, in tea and with theobromine, 3-7 dimethylxanthine, in chocolate. Paraxanthine, 1-7dimethylxanthine, for its part, is produced by the hepatic metabolism of caffeine operated by a cytochrome of 1A2 type. The effects of these methylxanthines on awaking, anxiety, neuroprotection in Alzheimer’s and Parkinson’s diseases, mood, schizophrenia and nociception are briefly considered. This review is concluded by indicating that these effects of methylxanthines may be modified by various associated substances, such as polyphenols displaying antioxydant properties.  相似文献   

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Except for four species of the Mertensinematinae (Molineoidea) not considered in this work, the Trichostrongylina parasitic in amphibians and reptiles, comprising 15 genera and 105 species, are reviewed. The morphological characteristics of each species are analysed. The most important characteristics are provided by the disposition of the caudal bursal rays, the morphology of the synlophe (at the oesophago-intestinal junction and mid-body level) and by the anatomy of the spicules. The species are classified into seven groups:Group 1: relict species with six lips and well-developed buccal capsule (six genera and 16 species).Group 2: ancient species with one or two primitive characters (eight genera and 15 species).Seventy-four species, without primitive characters, comprise the genus Oswaldocruzia which is subdivided into five groups.Group 3: Oriento-Ethiopian species with non-idiomorphic spicules with two to three tips (10 species).Group 4: Neo-Ethiopian species with non-idiomorphic spicules with numerous tips (11 species).Group 5: Holarctic species with idiomorphic spicules with the spicular fork divided above the distal third of the spicule length (24 species).Group 6: Continental Neotropical species with idiomorphic spicules and spicular fork divided within the distal third of the spicule length (21 species).Group 7: Caribbean Neotropical species with modified idiomorphic spicules, the three main branches of which are each divided into numerous tips (eight species).The geographical distribution of the species appears to be of greater significance than the host spectrum and suggests the following biogeographical hypotheses: Group 1, entirely Gondwanan, diversified during the Cretaceous era prior to the separation of the southern continents. The expansion of Group 2, which is represented by Gondwanan and Oriental species mainly from India, Malaysia and Indochina, could have occurred throughout South-East Asia at the end of the Cretaceous era when India collided with Eurasia. Group 3 could be interpreted either as a migration from Asia to Africa during the upper Eocene, or more likely during the Miocene, or, by a dispersion due to the migrations of Bufo melanostictus. Group 4 may result from the expansion of the former group in the Ethiopian region. Group 5 could be interpreted as a colonisation of western Europe and the Nearctic from Asia during the Tertiary. Group 6 could have arisen after the migration of the Neartic species to the Neotropical region during the Pliocene period and Group 7 by the expansion of the former group in the Caribbean.Amongst the Trichostrongylina, the relict and ancient genera parasitic in amphibians and reptiles can only be compared with the genera parasitic in birds and mammals, probably dating from the Palaeocene period (mainly marsupials and primitive insectivores). On the other hand, the genus Oswaldocruzia can be compared with other members of the Molineoidea parasitic in fissipeds, Pholidota and Chiroptera dating from a later period (Eocene) (see Durette-Desset, 1971). Thus, the Trichostrongylina of amphibians and reptiles are distinguished by the persistence of very old species, the evolution and the geographical distribution of which was arrested for millions of years, and by the existence (in some regions) of groups undergoing full evolutionary expansion.The new taxa proposed in the paper are: Bakeria (Moravec & Sey, 1986) status emend. (= Bakeria Moravec & Sey sub. g.), Ragenema n. g., Ragenema robustum (Baker, 1982) n. comb. (= Oswaldocruzia robusta), Typhlopsia quentini (Durette-Desset, 1980) n. comb. (= Trichoskrjabinia quentini), T. secundus (Pinnell & Schmidt, 1977) n. comb. (= Trichoskrjabinia secundus), T. gansi (Crusz & Ching, 1975) n. comb. (= Oswaldocruzia gansi), T. limnodynastes (Johnston & Simpson, 1942) n. comb. (= Oswaldocruzia limnodynastes), T. legendrei (Chabaud & Brygoo, 1962) n. comb. (= Oswaldocruzia legendrei).
Les Nématodes Trichostrongylina parasites d'Amphibiens et de Reptiles: problèmes taxonomiques, phylétiques et biogéographiques
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Palynological investigation from the Lower Palaeolithic site of La Pineta (Isernia, Molise) reports the environmental and climatic conditions of an old human occupation site in Italy, between the end of the Lower Pleistocene and the beginning of the Middle Pleistocene. The pollen record shows that the end of the Lower Pleistocene was marked by an arid episode. This is related to change in the climatic cycles periodicity from 41 to 100 ka, which occurred between 900 and 800 ka. The post-archaeological layers show new favourable moisture conditions at the beginning of the Middle Pleistocene, when the 100 ka cycles prevail. To cite this article: V. Lebreton, C. R. Palevol 1 (2002) 11–17.  相似文献   

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The radiopharmaceuticals are products that combine two very stringent regulatory requirements from two different authorities: as medicine from a pharmaceutical point of view (Afssaps) and as radioactive source with specific authorization (ASN). This article discusses the different regulatory constraints imposed by these authorities but suggests also that legislation is supposed to be modified in the coming years in collaboration with nuclear physicians and their Society (SFMN).  相似文献   

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Résumé Dans les cultures mixtes, la fermentation du glucose par Escherichia coli fournit des sources de carbone et d'électrons au Desulfovibrio desulfuricans qui est à l'origine de la formation des substrats utilisables par la souche de Chlorobium.
Mixed cultures of heterotrophic, sulfate-reducing and sulfur phototrophic bacteria
In mixed cultures, carbon and electron sources for Desulfovibrio desulfuricans are excreted by Escherichia coli from glucose fermentation. Desulfovibrio produces substrates for Chlorobium strain.
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Olivier Aynaud 《Andrologie》1994,4(4):440-444
Analysis of 92 clinically dysplasic penile lesions revealed the presence of atypical mitoses and/or abnormalities of the basement membrane, definitive of intra-epithelial penile neoplasia, in 90% of cases. In 18.3% of patients (mean age 31 years) there was a genital human papillomavirus (HPV) infection. Histological lesions were low grade (State I) in 64% of cases, and high grade (Stages II or III) in 33% of cases, of which 4% were carcinoma in situ. HPV oncogene sequences were detected by Southern blotting in 75% and 95% of low and high grade lesions respectively, including 100% of carcinomas in situ. Patients with Stage II and III lesions were 7 to 10 years older than those with Stage I lesions, although circumcised men showed significantly fewer lesions than non-circumcised men, a difference not seen for the presence of genital HPV infection. The good correlation between morphological, histological and virological features allows screening for and early treatment of penile dysplasias.  相似文献   

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