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1.
The clinical significance of antisperm antibodies (ASA) is highly controversial. A significant percentage of infertile men and women present immunity to spermatozoa, suggesting that ASA may interfere with the fertilizing capacity. ASA can act negatively on sperm parameters, sperm-cervical mucus interaction, gamete fusion and possibly also on the first step of embryonic development. ASA are present in approximately 2.8% to 26% of the male population and 0.2% to 1.6% of women. The pathogenesis of immunity to spermatozoa had not been fully elucidated: breakdown of normal protective mechanisms, i.e. blood-testis barrier, or epithelial barrier in women, and other mechanisms of immunological sperm tolerance, such as regulation of suppressor T lymphocytes. The indication for antisperm antibody testing is based on clinical and laboratory findings of infertile patients. In men, indictions for ASA testing include a history of genital disease, surgery for genital abnormalities, vasectomy, obstruction or injuries of the male genital tract, infection of accessory glands, long-standing infertility, alteration of semen parameters (agglutination, motility), mucus penetration, and reduced fertilizing capacity in IVF. In many cases, no etiological cause of autoimmunity is found and a genetic predisposition has been suggested. A majority of women do not develop antisperm antibodies, despite repeated contact with spermatozoa during their sexual life. Upper genital tract infection is the main cause of isoimmunization in females, although sexual practices, endometriosis, surgery for cervical neoplasia, recurrent spontaneous abortion and long-term infertility may also be involved. Sperm-cervical mucus impairment is the most obvious effect of immunization in women associated with IVF failure. Autoantibodies are frequently associated with antisperm antibodies. One of the consequences of the success of ICSI has been a decreased research effort to further the understanding of the origin and relevance of antisperm antibodies and specific antibody-antigen interactions. A better understanding of the natural history of immunological infertility would be useful for patient conseiling and to develop the most effective, efficient and safest management strategies. Such data could also be useful for the development of new tests and immunological methods of male contraception.  相似文献   

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Bouillenne  R. 《Plant Ecology》1954,5(1):66-71
Sans résuméReçu par la rédaction la 1.X.1953.  相似文献   

4.
G. Deroux  Cl. Faidy 《Hydrobiologia》1966,27(1-2):39-64
Summary The ecology of primary biological coatings (fouling films) is an important aspect of benthic ecology in general. Life in a fouling film is, to a large extent, governed by physico-chemical laws of contact surfaces and surface tension. These laws apply also to the microecology of the mesopsammon and surface microplankton. The conditions common to these ecological situations enforce common characteristics, both morphological and physiological, upon the organisms which inhabit them. Many of these organisms are therefore subject to certain general techniques.Nigrosin is employed as an impregnating agent, and the speed of activity of the micelles of nigrosin is under the control of 1) the colloidal nature of the medium, and 2) alteration of cytoplasmic structures by the action of formalin added to the solution as a fixative.The stain blackens a variety of organites having a filamentous ultrastructure: cilia, flagella, trichocysts, rhabdites, cnidocysts, spiny processes of thecae and shells, capsules, cuticles and cuticular setae. The excess nigrosin surrounding the specimen may be removed completely by simple washing.Two particular situations are discussed: that of microbiocoenoses which develop at the point of contact of water and air (for example, bacterial films) and that of glass slides immersed in water with a view to studying the organisms which colonize surfaces in a particular habitat.The method has been applied also for studies of plankton in general, to demonstrate the liberation of flagellate bodies by certain algae, and for preparation of mounts of various organisms such as rotifers, gastrotrichs and nematodes. The method is very useful for quickly obtaining a comprehensive picture of the protozoan fauna in ecological studies.  相似文献   

5.
J. Auger 《Andrologie》1997,7(4):433-442
Several studies have shown a good correlation between sperm motility and fertility though the microscopic evaluation of the percentage of motile sperm is highly subjective by nature. Therefore in the last decade, various objectives methods have been proposed to overcome this problem. Two types of methods were developed: The methods based on the analysis of images obtained by microphotography, microcinematography and microvideography and the global, undirect methods based on physical principles. Several systems based on video and image analysis (Computer Aided Sperm Analysis, CASA) have been developed and are used in numerous laboratories of reproductive biology. CASA technology offers the possibility to analyse some characteristics of sperm motion which are related to the fertilization potential and to develop new parameters related to some important aspects of sperm behavior such as hyperactivation. However, there is a large amount of interactions between the operator and the CASA machine. CASA instruments are not “ready-to-use” robots: the reliability of CASA depends largely on the expertise and training of the user and the application of standardized procedures and quality control schemes. By contrast, there is only minimal interaction between the operator and the Sperm Quality Anlyser which is a new device measuring and index of sperm motility highly correlated to the concentration of progressively motile sperm. The device uses light passed through a small sample of semen introduced in a capillary tube to detect variations in optical density that result from moving particles. The reproducibility of the measurements is excellent, the device is easy to use and this is a potentially useful tool for field-work studies. Further investigations of this device in the managment of male infertility is warranted. Finally, both types of objectives approaches are complementary to the conventional analysis of sperm motility and they will not replace it. Standardized procedures have been proposed by the World Health Organization for the subjective evaluation of sperm motility. Such procedures are very useful to reduce significantly the intra- and interlaboratory variations but internal and external quality controls schemes indicate that they are not sufficient to achieve acceptable levels of variation and regular quality controls followed by the definition and the application of corrective procedures are required.  相似文献   

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Résumé L'injection de substances irritantes de nature chimique variée perturbe les mécanismes qui contrÔlent la multiplication des hépatocytes du rat.Les très jeunes rats réagissent de faÇon intense et reproductible. 15 heures après l'injection il se produit une augmentation brève et intense du nombre des cellules entrant en phase S de sorte que les divisions cellulaires, qui normalement auraient été réparties sur les 30 ou 40 prochaines heures, débutent en l'espace de 2 heures seulement. La croissance hépatique a pris une importante avance qui est suivie par une période de diminution du nombre des mitoses due à une rétroaction inhibitrice.La réaction des rats plus âgés met en évidence un mécanisme inhibiteur permanent qui entraÎne une réponse moins intense et moins régulière.La production d'hépatocytes binucléés et polyploÏdes parait liée à ce mécanisme inhibiteur.La régularité et la sensibilité des réactions des très jeunes rats en fait un matériel de choix pour l'étude des mécanismes régulateurs de la croissance hépatique.
Control of multiplication and polyploidy of rat hepatocytesA study of the perturbations of physiological regulation induced by injection of irritants
Summary The injection of irritating substances of various chemical nature disturbs the mechanisms regulating the multiplication of rat hepatocytes.The reaction of baby rats is intense and reproducible. It results, 15 hours after the injection, in an increase of the number of cells entering the S phase, so that practically all the divisions which would normally have been scattered over 36 hours are initiated within 2 hours. This burst of synchronized mitosis corresponding to a 36 hours advance in the hepatic growth is followed by a decrease of mitoses due to a feed-back inhibition.The reaction of older rats brings to evidence a permanent inhibitory mechanism that results in a less regular and intensive response.The production of binucleated and polyploÏd hepatocytes seems to be correlated to this inhibitory mechanism.The regularity and sensivity of the baby rat reactions make them a choice material for the study of hepatic growth.
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8.
V. Labeyrie 《BioControl》1961,6(4):257-263
Summary The layings ofCassida deflorata Suffr. are parasited in southern France byMymaridae (Anaphoidea sp. andFulmekiella ovata soyka),Trichogrammatidae (Monorthochaeta nigra Blood.) andEulophidae (Foersterella flavipes Foerst. andTetrastichus rhosaces Walk.). In the Alpes-Maritimes, two successive generations ofMymaridae andTrichogrammatidae seem to attack the layings ofC. deflorata. In Corsica, parasitism byMymaridae andF. flavipes is very frequent and may be the essential regulating factor of the populations ofCassida. In the other regions that have been studied, although the large number ofCassida imagos appearing in spring show that mortality during the aestivation and hibernation is not the primary factor, it does not seem that the limitation of the populations is essentially caused by the activity of oophagous insects.   相似文献   

9.
Summary In a previous paper, we have used the density of the population as a sort of measure of the unknown size n of the isolates in Dahlberg's model, and shown an inverse relation between the coefficient of inbreeding and the density of the arrondissements. In the present paper, as the considered communes are smaller territorial subdivisions than arrondissements, we used, instead of the density, the population size of the communes. The results are even more eloquent as before: the inbreeding coefficients are large when the observed population size is small; the relative importance of second cousin marriages (233) versus cousin marriages (222) is greater in the latest period considered. The basic data have been collected for each commune in Belgium by Centre National de Radiobiologie et de Génétique.  相似文献   

10.
Adsorption, absorption and translocation of sodium were compared in three species showing an ascending degree in tolerance to salinity: red cabbage (tolerant) shows higher Root Cationic Exchange Capacity than tomato (sensitive) or radish (intermediate). At low NaCl concentrations, tomato accumulates the greatest quantities of sodium; but Na+ translocation remains proportional to the quantity absorbed in the three plants. At high salt concentrations, diffusive phenomena explain similar accumulation in every plant, but red cabbage quickly localises 50% of Na+ amount in cotyledons, while this element stays stored in tomato roots. The consequence of these three nutrition phases was discussed in relation to the behaviour observed at the germination time of these same plants.   相似文献   

11.
Résumé Les relations antigéniques entre einq rickettsies pathogènes aux Invertébrés sont étudiées par agglutination. Cette comparaison met en évidence que le genreRickettsiella ne constitue pas au point de vue immunologique un ensemble homogène. On définit deux groupes sérologiques distincts:R. melolonthae, R. tipulae etR. cetonidarum appartiennent au groupe I; le groupe II est actuellement consitué parR. grylli etR. armadillidii.
Summary The antigenic relation between five rickettsiae pathogenic to Invertebrates have been studied by agglutination. This comparison shows that the genusRickettsiella does not form and homogeneous group from an immunological point of view. Two separate serological groups are defined:R. melolonthae, R. tipulae andR. cetonidarum belong to the Ist group;grylli andR. armadillidii are forming the IInd group now.


Ce travail a été réalisé en partie dans le cadre d'une convention D.R.M.E.  相似文献   

12.
Conclusions Les différents rythmes biologiques des plantes que nous avons passés en revue sont en rapport étroit avec la biométéorologie. Leur étude peut avoir pour but une meilleure connaissance de la biologie, soit qu'on étudie leur rÔle dans l'adaptation au milieu, soit qu'on mette en évidence et qu'on étudie leurs mécanismes physiologiques internes. Mais leur étude peut aussi avoir pour but une meilleure connaissance de la météorologie, si on met en évidence des cycles écologiques mal connus(voir les problèmes de l'influence de la lune ou des taches solaires par exemple) ou bien encore si les observations phénologiques permettent d'étudier la variabilité des cycles écologiques et de caractériser un climat en termes de données biologiques.Ces points de vue sont indissociables quand on approfondit les problèmes; ils n'ont de sens que les uns par rapport aux autres.  相似文献   

13.
The most frequent cause of testicular injuries is blunt trauma (following sports injuries or road accidents). Penetrating injuries are rare. Increased scrotal volume and a painful testis are the main symptoms and require scrotal ultrasonography. Scrotal ultrasonography is very sensitive and specific for testicular rupture or intratesticular haematoma. Two out of three patients with testicular injuries require surgical exploration. Secondary complications due to delayed management of trauma are testicular atrophy, sterility or impotence. Penile fracture (rupture of corpus cavernosum) is due to direct trauma by an excessive force applied to an erect penis. Swelling, penile ecchymosis, penile curvature and pain are the usual symptoms of rupture of the tunica albuginea. Urethral injury must be ruled out. Cavernosography, ultrasonography or MRI are not considered mandatory to establish a diagnosis but can be prescribed in the absence of typical signs or symptoms. Early surgical exploration and repair ensure a better outcome. Secondary complications are penile curvature, chronic pain and impotence.  相似文献   

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Zusammenfassung Es wurde die Reaktion von Bienen auf monochromatische Lichter und variabler Intensität im Spektrum von 300 bis 665 m untersucht. Das Spaltbild eines Spektrographen wurde auf die Wand einer Versuchskammer vergrössert abgebildet. Als Test der Reaktion wurde die Zahl der Bienen genommen die während einer vorgegebenen Zeit auf das Spaltbild zugehen und ihm entlanglaufen.Dabei ergaben sich folgende Resultate: 1) Eine lineare Abhängigkeit zwischen der Reaktionszahl und dem Logarithmus der verwendeten Spektralenergie für alle verwendeten monochromatischen Lichter. 2) Eine spektrale Empfindlichkeitskurve mit zwei Maxima bei 550 und bei 365 m. Das Letztere ist etwa doppelt so intensif wie das im Sichtbaren.Die gefundenen Resultate bestätigen z. Teil die Resultate Bertholf's und ergänzen sie. Es konnte gezeigt werden, warum bei Sander das Max. bei 365 m nicht auftritt.Weiterhin konnte nachgewiesen werden, dassApis mellifica keinerlei Lichthautsinn besitzt.  相似文献   

17.
Ultrasonography (US) is presently routine part of the investigation of infertile men with low volume ejaculate. It provides excellent depiction of the congenital or acquired obstructive lesions of the reproductive system, particulary in its distal part. For 10 years, we performed a US examination of the kidneys, the scrotum contents and transrectal US (TRUS) in every case a excretory cause of male hypofertility could be suspected. In selected patients, MR imaging (with endorectal coil) appears usefull. We describe the normal and abnormal anatomy of the epididymis, vas deferens, seminal vesicle (SV) and ejaculatory ducts in male infertility with US and MRI. Dilatation of the small ducts in the epididymis and sometimes in the testis at scrotal US is suggestive of a downstream obstacle. Sometimes these dilatation could appear as small hypoechoic areas in the epididymis. In contrast, post-inflammatory changes are hyperechoic but often associated with dilatations. TRUS permits to confirm the absence of the vas deferens in congenital bilateral absence of vas deferens (CBAVD): it shows the absence of the ampullae and severe abnormalities of the SV. In case of unilateral absence of the vas deferens, the association with a homolateral kidney agenesis does not lead to the screening for mutations in the cystic fibrosis gene, but suggests a wolffian duct abnormality. MRI (with endorectal coil) is indicated when TRUS is unconclusive. Scrotal US permits to guide semen aspiration and TRUS is indicated to eliminate a distal obstruction when a surgical anastomosis is planed. TRUS (as well as scrotal US) can suggest an obstacle when dilatation of one or several segments of the seminal tract is observed. Sometimes the cause is obvious with imaging: CBAVD, prostatic cyst, inflammatory and post-infectious changes, lithiasis etc. However, it remains many cases where US is only one component of the therapeutic decision, besides clinical examination, sperm count, FSH level and biochemical sperm markers.  相似文献   

18.
Résumé Le virus de la densonucléose est thermorésistant. Il n'est pas inactivé après traitement avec des solvants de lipides. Aucun pouvoir hémagglutinant n'a été mis en évidence avec des érythrocytes d'espèces variées. Ces propriétés sont comparées à celles desParvovirus.
Summary The densonucleosis virus is thermoresistant. It is not inactivated after treatment with lipid solvents. Attempts to demonstrate hemagglutination of DNV, using different erythrocytes, were unsuccessful. These properties are compared to those of Parvoviruses.
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19.
Résumé Les organes chordotonaux présents dans les différentes pièces céphaliques de la larve du Speophyes peuvent être classés en deux catégories.La première catégorie regroupe les récepteurs scolopidiaux de l'antenne, du labium et du palpe maxillaire. On peut les comparer au scolopidium de l'organe tympanique du Criquet décrit par Gray (1960). La deuxième catégorie comprend les récepteurs scolopidiaux de la mandibule et de la lacinia: ils sont du amphinématique.Le sensille scolopidial de la galea représente un type intermédiaire.Nous signalons l'importance des structures de soutien et de fixation, qui doivent permettre une bonne transmission de toutes les déformations et tensions subies par le tégument. Nous discutons du rôle joué par la gap junction qui unit les deux dendrites dans les scolopidium. de la deuxième catégorie.Enfin nous essayons d'établir des hypothèses sur le fonctionnement des scolopidium.
Fine structure of the chordotonal organs of the head appendages of Speophyes lucidulus larva
Summary The chordotonal organs located in the various head appendages of the Speophyes larva, can be divided into two classes.The scolopidial receptors of the antenna, the labium and the palpus maxillae belong to the first class. They can be compared to the scolopidium of the locust tympanic organ described by Gray.—The second class contains the scolopidial receptors of the mandible and the lacinia: their type is amphinematic.The scolopidial sensilla of the galea represents an intermediate type.We demonstrate many supporting and fixation structures which probably allow a good transmission of all the deformations and strains affecting the tegument.The function of the gap junction which connects the two dendrites in the scolopidia of the second class is discussed.Finally we try to formulate hypothesis of the functioning of scolopidia.
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20.
E. Boltovskoy  H. Lena 《Hydrobiologia》1971,38(3-4):441-451
Résumé La faune des Thécamoebiens fut étudiée dans deux étangs (La Brava et De los Padres) situe dans la Province de Buenos Aires (Argentina). Le nombre d'espèces trouvé en tout a été de 14, quelques-unes desquelles représentées par de différentes formae. Une nouvelle forma Centropyxis compressa (Cushman), forma brava n.f. a été trouvée et décrite, et une espèce de Pontigulasia a été proposée en nomenclatura aperta.
Summary The Thecamoebiens of two lakes (La Brava and de los Padres) located in the Province of Buenos Aires (Argentina) were studied. The total number of species found is 14, several of them are represented by various formae. A new forma was found and described, namely Centropyxis compressa (Cushman), forma brava n.f. and one species of Pontigulasia was put in nomenclatura aperta.


Departamento de Ciencias Biologicas, Facultad de Ciencias Exactas y Naturales Universidad de Buenos Aires  相似文献   

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