首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
2.
3.
4.
5.
6.
7.
8.
9.
The content of abscisic acid in the developing fruits of two cultivars of pear (Pyrus communis L.) was determined by UV spectrophotometry and by a colorimetric method based on the possibility of the lactone corresponding to abscisic acid to give a purple colour when sodium hydroxide is added. The young fruits were harvested either from trees treated with gibberellic acid (GA3), for the purpose of inducing parthenocarpy, or from untreated trees. High levels of abscisic acid were associated with abortion and abscission of young fruits (June drop). There was little difference between fruits of GA3-treated and untreated trees of the cultivar Passe-Crassane. In the other cultivar, ‘Doyenne du Comice’, the level of abscisic acid in the fruits of GA3-treated trees was about twice as high as in control fruits and seemed to be directly related to the number of fruits per tree.  相似文献   

10.
11.
12.
Résumé A la suite de recherches antérieures intéressant la vascularisation de la trompe utérine et celle de l'ovaire, la présente étude concerne la microvascularisation de la muqueuse vaginale chez la Femme et se fonde sur l'examen de dix vagins humains prélevés chez des sujets en période d'activité génitale, vagins dont le système vasculaire est injecté à l'encre de Chine gélosée.L'étude de l'angioarchitectonie de la muqueuse vaginale en général laisse apparaître un dispositif vasculaire spécifique de cette dernière et représenté au niveau du chorion par des artérioles superficielles qui s'arborisent en de multiples branches se résolvant en un réseau capillaire sous-muqueux; ce dernier est constitué d'une part, d'un dense réseau capillaire à mailles ovalaires ou polygonales, étalé sous la couche basale de l'épithélium malpighien, d'autre part, d'anses capillaires intra-papillaires, sensiblement perpendiculaires à l'épithélium malpighien et se répétant à intervalles réguliers. Ce réseau capillaire est draîné par un plexus veineux étendu que résument de volumineuses veines au calibre irrégulier.Les variations de cette angioarchitectonie au cours des diverses phases du cycle ovarien sont essentiellement marquées au cours de la 2e phase de ce cycle où elles se caractérisent par une augmentation de calibre des artérioles comme des capillaires et surtout par l'accroissement de la hauteur et de la spiralisation des anses capillaires.
The angioarchitectony of the submucous network of the human vagina and its variations during the ovarian cycle
Summary The microvascularization of the vaginal mucosa has been investigated on 10 human vaginae taken from autopsies of women having been in their sexual active period, the vascular system of the vaginae being injected with solutions of China ink and gelose.The angioarchitectony of the vaginal mucosa shows a specific vascular pattern. The latter is represented at the level of the stroma by superficial arterioles which divide into multiple branches giving rise to the submucous capillary network. This network consists on one hand of a thick capillary plexus with ovale or polygonal stitches, spread under the basal layer of the malpighian epithelium, and on the other hand of intrapapillary capillary creeks arranged in regular intervals and perpendicularly oriented to the malpighian epithelium. This capillary network is drained by a wide spread venous plexus connected with big veins of irregular calibre.The variations of this angioarchitectony are especially pronounced during the second part of the menstrual period, when the calibre of the arterioles as well as that of the capillaries creeks grow in height and become spiralized.
  相似文献   

13.
Jaglin, J.-C. & Paris, F. 1992 04 IS: Exemples de tératologie chez les Chitinozoaires du Pridoli de Libye et implications sur la signification biologique du groupe. [Teratologic cases among Pridolian chitinozoans from Libya and implications on the biological interpretation of the group.] Lethaia , Vol. 25, pp. 151–164. Oslo. ISSN 0024–1164.
Fairly numerous chitinozoans displaying morphological anomalies are recorded in Late Silurian subsurface material from Western Libya. The individuals described and illustrated in our paper range exclusively in a short interval at the top of the investigated sequence. These abnormal vesicles are interpreted as teratologic cases related lo an event of unknown origin. From our conclusions, the hypothesis of vegetative reproduction stages stated by previous authors seems unlikely. Therefore we still interpret the chitinozoan vesicles as eggs (or to a lesser extent as spores) of marine organisms. * Libya, Chitinozoans, Silurian, teratology, chitinozoan affinities .  相似文献   

14.
Embryo dormancy of Taxus baccata var. fastigiata is eliminated when cultured continuously in nutritive liquid medium. An equivalent percentage of germination is obtained when the embryos are transferred to agar medium after 8 days of liquid culture. There is no morphological development of the embryo during the period in the liquid medium. But we have ascertained that water-soluble germination inhibitors present in the embryo are leached out into the medium, permitting germination. Germination is totally absent when the embryos are cultured continuously in distilled water, alone or with minerals; incidental in sucrose solution; and maximal when the medium contains sucrose and Ca2+ or K+ ions. The extent of germination on agar medium depends upon the composition of the liquid medium in which the embryos are cultured for the initial 8 days. But this preliminary culture in the liquid medium does not always remove the endogenous inhibitors, irrespective of its composition. This can be achieved only in the presence of sucrose; and this process can be made more effective by the addition of Ca2+ ions.  相似文献   

15.
N. Zencirci 《Hydrobiologia》1980,69(1-2):179-186
Résumé Nous avons étudiés les effets toxiques de l'accumulation de l'étain et du plomb sur les G. pulex d'eau douce et les G. locusta (Crustacés: Amphipodes) marin.Les expériences ont été faites dans des solutions de métaux d'eau douce et d'eau marine. Les concentrations de métal utilisées sont de 10 ppm, de 1 ppm et de 0.1 ppm. Les résultats nous ont montrés que les solutions de plomb sont plus toxique que les solutions de l'étain et les G. locusta sont plus sensibles que les G. pulex.Les valeurs de l'accumulation de métal ont été determinées par spectrographie des rayons X. Pour les deux espèces, une grande accumulation d'étain a été rencontrée dans le système digestif, la cuticule et l'hemolymphe et une accumulation de plomb a été rencontré dans le système digestif et la cuticule.
The effects of tin (SnCl4.5H2O) and lead [Pb(NO3)2] on Gammarus pulex (L.) and Gammarus locusta (L.) have been studied. Three differents solutions (10 ppm, 1 ppm, 0.1 ppm) were applied for two metals. Lead was found to be more toxic than tin. The residues of metals in the organes and tissues of two species were determined by X ray spectrophotometry.
  相似文献   

16.
Axenic and holoxenic (conventional) rats were fed a diet containing trace amounts of [2,4-3H]cholic and [24-14C]chenodeoxycholic acids. In the feces of both groups of rats, the percentage of labelled bile acids which were 3H-labelled was slightly different. In the experimental conditions used, the intestinal microflora only slightly modified the synthesis of 12α-hydroxylated bile acids.  相似文献   

17.
There are numerous controverses concerning the relationship between the presence of leukocytes in semen and male infertility. In the aim to determine the impact of pyospermia on sperm quality, we have realised a retrospective study in which we analysed and compared semen parameters and abnormalities frequencies between pyospermic and non pyospermic infertile patients. 833 spermiograms were included in this study. They were done in accord with WHO method. Leucocytes identification was performed by cyto-enzymologic method that reveals myelo-peroxydase in polymorphonuclear granulations. Pyospermia was considered when number of leucocytes was more than one million per millititre of sperm. The non pyospermic group was composed by sperm with leucocytospermia less than 50.000 per millilitre. The prevalence of pyospermia was 5.88%. There was not significative difference of semen parameters (volume, motility, morphology, number of spermatozoa and viability) between pyospermic and non pyospermic groups. In the other hand, no correlation was found between leucospermia and semen parameters. However, oligospermia was significantly more frequent in pyospermic group (40.8%) than in non pyospermic group (20,3%). Inversly, the frequence of teratospermia was significantly higher in non pyospermic group (47.2% vs 34.1%, p<0,05). These results suggest that inflammation and/or infection associated with pyospermia is complicated by reduction of spermatic ducts permeability. Although, the leucocytes would act in removing amorphous gametes by phagocytosis. No relationship was established between pyospermia and infection. In future, a prospective study would be done with exhaustive exploration of pyospermia etiology, with hopes to clarify the true link with infection and autoimmune reaction and to determine the effect of pyospermia on glandular activities in male genital tract and on functional properties of spermatozoa.  相似文献   

18.
Résumé L'injection à l'aide d'une solution d'encre de Chine gélosée du réseau vasculaire de la trompe utérine humaine, permet d'observer une angioarchitectonie typique du réseau sous-muqueux.Une étude histologique des vaisseaux préalablement injectés permet par ailleurs de mieux préciser ce dispositif vasculaire.La mise en évidence de variations de la microvascularisation au niveau de la muqueuse tubaire pendant le cycle ovarien autorise à concevoir l'angioarchitectonie de la muqueuse tubaire comme dépendant étroitement d'influences hormonales.Les variations de l'architecture vasculaire de la trompe au cours du cycle ovarien (fig. 5; fig. 6; fig. 7) sont, sur le plan morphologique, comparables aux modifications vasculaires cycliques de l'endomètre (Markee, 1932; Wilkin, 1960) et traduisent, les premières comme les secondes, une réponse du système vasculaire de la muqueuse tubaire et de celui de la muqueuse utérine à la sécrétion hormonale de l'ovaire.Comme au niveau de l'endomètre, au terme de la lère phase du cycle, en fin de phase proliférative (Dalgaard, 1946), la spiralisation des artérioles de la muqueuse tubaire (fig. 5, A) semble débuter à l'origine de chacune d'elles pour s'étendre vers le sommet du pli ou de la frange au début de la 2ème phase du cycle, folliculino-lutéinique (fig. 6, A). A la manière des artérioles de l'endomètre (Ober, 1949; Wilkin, 1960), à la fin de la 2ème phase du cycle en phase secrétoire tardive, la spiralisation des artérioles de la muqueuse tubaire va s'accentuer considérablement pour atteindre un maximum au moment de la menstruation (fig. 7, A).Le système veineux et le réseau capillaire subissent une vasodilatation marquée au moment de l'ovulation et maximale en phase secrétoire tardive lors de la période prémenstruelle.
The angioarchitecture of the submucous network of the human uterine tube and its variations during the ovarian cycle
Summary Injection of a solution of India ink and gelatine into the vessels of the human uterine tube allows one to observe the angioarchitecture of the submucosal vascular network. This injected vascular system was examined histologically.The variations of the microvascularisation in the tubal mucous membrane during the ovarian cycle reflect a close dependence of the mucosal vascular system on hormonal factors. The morphological variations of the tubal vascular architecture during the ovarian cycle are similar to the cyclic vascular alterations in the endometrium, demonstrating an intimate relationship between the tubal and uterine mucosal vessels, and the ovarian hormones. As is true of the endometrium, at the end of the first part of the cycle, that is the end of the proliferation phase, the arteries of the tubal mucosa become increasingly coiled. These changes are first observed at the origin of the vessels and proceed towards the outer layers of the mucosa at the beginning of the second part of the cycle. At the end of the second phase of the cycle, during the late secretory phase, the coiling of the arteries increases further to reach its maximum during menstruation. The same can be observed in the arterioles of the endometrium.The venous system and the capillary bed undergo a marked vasodilatation, reaching its maximum during the late secretory phase, at the time of premenstruation.


Herrn Prof. Dr. K. Goerttler zum 70. Geburtstag in Verehrung gewidmet.  相似文献   

19.
20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号