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1.
Seminal liquefaction corresponds to a proteolysis of glycoproteins and could also result in a lysis of linked glycans involving glycosidases. It is well known that α-1-4 glucosidase is a real epipidymal marker. The aim of this study is to point out new markers among the glycosidases and especially β-D-mannosidase, α-L-fucosidase and N-acetyl-β-D-glucosaminidase. There is no correlation between the three enzymatic activities and the sperm count. Moreover in case of azoospermia enzymatic activities were always present. The variations observed are both quantitative (β-MAN activity is significantly decreased) and qualitative (modifications of the relative proportions of the different enzymatic forms) according to the etiology of azoospermia.  相似文献   

2.

XVIème Congres de la Societe d’Andrologie de Langue Francaise Issy-Les-Moulineaux 9-11 Décembre 1999

Résumés des communications orales et affichées  相似文献   

3.
4.
H. A. Guénin 《Genetica》1951,25(1):157-182
Sans résumé Avec 81 figures dans le texte  相似文献   

5.
Attempts to prepare 1,2:5,6 and 2,3:5,6 di-unsaturated sugars starting from 3,4,6-tri-O-acetyl-1,5-anhydro-1,2-dideo xy-d-arabino-hex-1-enitol or from ethyl 4,6-di-O-acetyl-1,5-anhydro-2,3-dideoxy-α-d-erythro-hex-2-enopyranoside led to 1,5-anhydro-1,2,6-trideoxy-l-threo-hex-5-enitol and its 3,4-diacetate. Hydrogenation and hydrogenolysis of the unsaturated chloro and fluoro derivatives afforded 1,5-anhydro-1,2,6-trideoxy-d-arabino-hexitol and ethyl 4-O-acetyl-2,3,6-trideoxy-α-d-erythro-hexopyranoside.  相似文献   

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Spinal cord-injured men with ejaculation disorders can have children by means of Assisted Reproduction Techniques (ART). The possibilities of procreation of couples in which the man is praplegic or tetraplegic, have been improved over the this last decade by progress in the treatment of ejaculation disorders and the development of new ART techniques such as ICSI. Sperm quality is usually impaired in these patients. The indications for ART in spinal cord-injured patients are similar to those of other forms of male infertility. According to WHO recommendations, sperm preparation must be performed together with morphological study of spermatozoa to select the most appropriate ART technique, giving preference to so-called “simple” ART techniques, such as Intra-Uterine Insemination (IUI). Small studies have been conducted and showed that the clinical pregnancy rate per cycle was comparable to that observed in non-neurological patients. Autopreservation of sperm must be rapidly programmed to avoid repreated electrostimulation techniques and as a security measure before performing ART. A multicenter study should be conducted to pool data from all French centres.  相似文献   

8.
Sans résuméLaboratoire de Cryptogamie du Musuem National d'Histoire Naturelle de Paris  相似文献   

9.
This study focuses on how allelopathic mechanisms may be involved in the floristic composition and dynamics of Cistus albidus shrubbery. Allelopathic potential of essential oils was measured for Lactuca sativa (toxicity for other species) and Cistus albidus (self-toxicity). These oils have little effect on germination but significantly increase, even in low quantities, the number of unviable seedlings and inhibit normal seedling growth. These results explain, at least partially, the existence of monospecific stands over several years and the lack of natural regeneration of the Cistus albidus populations. Bioassays performed using natural aerial leachates of Cistus albidus revealed no significant effects on the above-mentioned parameters. Leaching does not seem to be an important means of allelochemicals release. Nevertheless, essential oils have been quantified in litter and soil, indicating a possible occurrence of allelopathy in such ecosystems.  相似文献   

10.
Résumé Des expériences d'associations d'épithélium gastrique de foetus de Lapin et de mésenchyme homologue ou hétérologue, partielles ou par membrane filtrante interposée, mettent en évidence l'existence de deux types de facteurs inducteurs.Le premier facteur induit la morphogenèse de l'épithélium. Il est thermostable et hautement diffusible.Le deuxième facteur, organospécifique, est plus ou moins favorable à la différenciation de l'épithélium gastrique suivant la nature du mésenchyme. Faiblement diffusible et thermolabile, il est élaboré dans la phase cytoplasmique des cellules mésenchymateuses.
Action and properties of inductive factors proceeding from gastric and heterologous mesenchymes
Summary Experimental associations of gastric epithelium of the Rabbit foetus with homologous or heterologous mesenchyme, separated by membrane filter or partially associated, permit us to prove the existence of two types of inductors.The first factor induces the epithelial morphogenesis. It is thermostable and highly diffusible.The second factor, organospecific, is more or less favorable to the differentiation of the gastric epithelium according to the nature of the mesenchyme. Lightly diffusible and thermolabile, it is elaborated in the cytoplasmic phase of the mesenchymal cells.
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The cytokinin activities of various 6-acylaminopurines, 6-alkylaminopurines, 6-acylamino-9-benzyl-purines as well as a series of isosteric-nitrogen derivatives of N6-(γ, γ-dimethylallyl)adenine (I6Ade) have been tested using the tobacco pith and the pea bud bioassays. The interactions between active, slightly active and inactive compounds have been studied with the last assay. Acylation decreases the biological activity; e.g., N6-benzoyl and N6-furoyladenines are less active than Na6-benzyladenine and kinetin. Substitution at the 9-position reduces (tobacco-pith assay) or suppresses (pea-bud assay) the phytohormonal activity of otherwise active 6-acylaminopurines. In isosteric derivatives, maximum activity occurs when the side chain has the same length as in 16Ade. After the analysis of interactions between more or less active compounds, it is suggested that the differences in cytokinin activity could be related to unequal affinities for a hypothetical receptor site.  相似文献   

13.
From a survey of 30 species and varieties of ladybugs the presence of alkaloids appears to be correlated with the existence of aposematic colour and not with being carnivorous or phytophagous. The alkaloids described until now all belong to the Coccinellini and are closely related, but other types of bases have been detected in some genera. The observed distributions are in agreement with the modern taxonomy of the family.Ladybug alkaloids constitute an effective defence against ants, Myrmica rubra, and quails, Coturnix coturnix, but all the beetles containing alkaloids do not possess the same degree of protection. Individual quail react differently towards moderately protected species.The bioassay used for the first isolation of coccinelin is described. The repulsive activities of aqueous solutions of coccinellin and convergin towards ants have been compared.  相似文献   

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The Glénan Archipelago was investigated, from the surface to a depth of 60 m, byScuba diving. Four distinct communities (“peuplements”) have been determined that fit into the system of zonation defined by the Genoa Symposium (1957). The results are compared with observations made in the English Channel (Cabioch 1968) and in the Atlantic Ocean (Glemarec 1971). Since illumination depends upon the angle of the rocky face, photophilic species exhibit a maximum range when the rock surfaces are horizontal. The sublittoral zone is dominated by laminarians. They form two distinct communities with the animal and vegetal species they overshadow. The upper community is characterized byLaminaria digitata (Linné)Lamouroux (horizontal rocky face from 0 to 6 m; vertical rocky face from +0.5 to ?3 m). The lower cummunity, characterized byL. hyperborea (Gunner)Foslie has a greater vertical extension (horizontal: ?6 m to ?26 m; vertical: ?3 to ?30 m). The circalittoral zone is colonized by several animal species growing in a ramified manner: the upper community is characterized by Axinellidae (?30 m), the lower byDendrophyllia cornigera (Lamarck) (?55 to ?60 m). Upright algae disappear somewhere between ?40 and ?47 m.  相似文献   

16.
《L'Anthropologie》2021,125(2):102863
The Upper Paleolithic burials currently known in Italy represent a rich and important group which constitutes the major part of the European sample. Among these burials, those attributed to the Gravettian are concentrated in two regions, Liguria and Puglia. Epigravettian burials were found in most parts of the peninsula and in Sicily. Grave goods are often very rich, especially in Gravettian burials. With regard to the anthropological characteristics of the buried, research has focused mainly on postcranial skeleton and on the information it can give us about weight, stature and somatic proportions. Among the Gravettians, Ligurian males reach the highest stature. The average height decreases from Gravettian to Epigravettian, as already observed in the European sample.  相似文献   

17.
Treatment of 1,2:5,6-di-O-isopropylidene-α-d-ribo- and xylo-hexofuranos-3-uloses with (difluoromethylene)triphenylphosphorane and (chlorofluoromethylene)-triphenylphosphorane gave unsaturated, ramified halogeno sugars in good yield. Treatment of the chlorofluoromethylene derivatives with lithium aluminum hydride gave stereospecifically the corresponding fluoromethylene derivatives with inversion of configuration at the double bond. The configuration was determined by 1h- and 19F-n.m.r. spectrometry.  相似文献   

18.
The E.A.U. (European Association of Urology) published its Guidelines on Urinary and Male Genital Tract Infections in 2001. In the chapter devoted to prostatitis, epididymitis and orchitis, the E.A.U suggests a classification distinguishing prostatitis (usual clinical picture and demonstrated infection) from chronic pelvic pain syndrome (same clinical picture without demonstrable infection). Prostatitis is divided into three categories: acute bacterial prostatitis (type I), chronic bacterial prostatitis (type II) and asymptomatic inflammatory prostatitis (histological prostatitis, type IV). Type I and II prostatitis are considered here. The E.A.U. guidelines do not mention recurrent prostatitis. The authors discuss whether or not recurrent prostatitis should be distinguished from chronic prostatitis by raising three questions: does the literature provide precise data in favour of this distinction? Does this theoretical distinction have any practical consequences? Is this distinction feasible, especially in general practice? The Stanford sesearch team (Stamey and Shortliffe) has provided documented bacteriological data demonstrating recurrence of prostatitis with different bacteria in some cases and persistence of the same pathogen in other cases. The main consequence of these two situations concern treatment (which antibiotics? for how long?) On the basis of personal unpublished data, the authors discuss the feasibility of this distinction in general practice. They show that, in the case of several recurrences of prostatitis per year, it may be difficult to distinguish recurrent prostatitis from chronic prostatitis. They also show that the duration of symptoms is not a sufficiently discriminant factor and that bacteriological findings should be considered. In conclusion, recurrent prostatitis is a particular disease which should be distinguished from chronic prostatitis. The main consequence of this distinction concerns several unresolved questions about the therapy of recurrent prostatitis. In general practice, the distinction may be difficult when only routine bacteriological tests are available. The use of Meares and Stamey’s four glass technique is unusual in this setting, making it difficult to confirm prostatic disinfection.  相似文献   

19.
Dr. W. F. Wassink 《Genetica》1935,17(1-2):103-144
Sans résumé  相似文献   

20.
《Comptes Rendus Palevol》2002,1(7):499-515
The important collection of Crustacea assembled by dˈOrbigny during his voyage of exploration in South America (1826–1834) was studied by Henri Milne Edwards and Hippolyte Lucas (1842–1844) in their contribution to the natural history of the Voyage en Amérique méridionale. In the present paper, this material, mainly crabs, deposited in the dry collection of the ‘Muséum national dˈhistoire naturelle’, Paris, is reviewed. The authors of the described taxa and their dates of publication are specified, lectotypes are designated, and a list of the currently valid taxa is provided.  相似文献   

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