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The order Podostemales are two pantropical families of aquatic plants living in running water: Tristichaceae (five genera, ten species) and Podostemaceae (35 genera, 200 species). Pollen of the 26 genera and 62 species studied is characterized by: a granular infratectum in which the granules are sometimes organized as columellae like units, and a lamellar and/or granular endexine in all pollen types, single or in dyads. Most of the apertural characters and the ornamentation of the exine allow us to distinguish the previously established taxonomic groups: Weddellinoideae have tricolporate rugulo-areolate, pollen with a smooth apertural membrane; in Tristichoideae, pollen is periporate and the microspines of the tectum and of the apertural membrane are massive; in Podostemaceae, the tectal spines with their broad bulbous base are formed from numerous masses of sporopollenin, the endexine is microfibrillar at the base, the apertural membrane is constituted of structured ectexinous masses, and the endexine is granular at the aperture. Presence of the tricolporate pollen type associates the Podostemales with the higher eudicotyledons. Most of the pollen characters of Podostemales and their variations are found among advanced Rosidae (Hamamelidales, Polygalales, Santalales, Violales, Euphorbiaceae).  相似文献   

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Résumé Le transfert d'isotopes (198Au) entre les colonies filles deFormica polyctena, à partir d'une des colonies marquées, suit des voies préférentielles, malgré l'activité des butineuses plus ou moins également réparties entre les fourmilières. Certaines colonies procèdent à des échanges actifs de glucides et d'isotopes, d'autres ne reçoivent rien ou presque rien. Le transfert est limité d'ailleurs à une petite fraction de la quantité totale qui a été distribuée.
Summary Isotope exchanges (198Au) between the daugther-colonies ofFormica polyctena are strongly anisotropes, even when foragers activity between the different nests is almost the same. Some nests exchange easily the isotope (and glucides) with the colonies in close neighbourhood, some other do not; only a small fraction of the isotope is transferred, even in most favourable cases.
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《L'Anthropologie》2021,125(5):102960
There are two lithic industries in the beginning of the Upper Paleolithic including the vestiges that have been discovered in the islands of Oshumi, close to the island of Kyushû. This lithic industry is characterized by the presence of axes with partially polish cutting, denticulate, hammers and millestones that are common in western Japan. It is characterized by numerous lithic instruments for the treatment of the plant food. The discovered vestiges of which one found the pebbles cluster inside pitfalls that are the oldest on the archipelago of Japan. According to these particularities of the lithic industry and vestiges, it is likely that this human group is semi-settled. And this human group of the beginning Upper Paleolithic was identical typologically and technically to the human group of the island of Kyushû. Therefore, it is possible that they came down from the southbound Kyushû Island, to the concerned islands. As for the islands of Amami, we investigated sites, nevertheless all that have been unearthed, in small extents provided a small quantity of the archaeological material. Indeed, one could not seize very well retails until now. There is a mixture of various, non-resolute opinions. The islands of Okinawa and those of Sakishima in southern extremity of the Japanese territory provided humans rests of the Upper Paleolithic, nevertheless no lithic industry of the same time have been found. Thereafter of the situation, the origins of the culture and the technique concerned the human rests remain unclear.  相似文献   

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L. Lison 《Protoplasma》1928,4(1):367-387
Resumé Dans la première partie de ce travail, nous avons montré que, contrairement à la conception deFauré-Fremiet, les mouvements que présentent les amibocytes des Invertébrés à l'état actif ne peuvent s'expliquer par le seul jeu des forces de tension superficielle. Ces forces, si elles interviennent das le mécanisme du mouvement, ne peuvent en expliquer l'origine; l'amibocyte, tel qu'il est constitué, est un système inerte, incapable de se mouvoir sans apport d'énergie.Les faits exposés dans la seconde partie montrent qu'on peut dissocier physiologiquement le granuloplasme nucléé de l'hyaloplasme. Des coelamibocytes d:'Allobophora longa soumis à l'action de toxiques ou d'anesthésiques peuvent présenter des mouvements de leur hyaloplasme longtemps après que le granuloplasme nucléé a cessé toute activité fonctionnelle (mort ou anesthésie). Ces substances inhibent les activités complexes du granuloplasme, probablement les activités diastasiques, tout en conservant intactes les activités d'ordre plus simple qui président aux mouvements de l'hyaloplasme.  相似文献   

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Conclusions L'invasion de la cornée par les leucocytes est tardive. Ces cellules sont évidemment destinées à servir de moyen de protection contre les microbes, mais elles ont encore probablement une autre fonction, qui reste inconnue, car elles se transforment par métaplasie en éléments différenciés, les cellules en épieu, décrites par Ranvier, dont la durée de vie est limitée.Cette métaplasie s'effectue au cours d'un processus spécial, qui m'a paru fort étrange lorsque j'ai commencé à l'étudier; mais la netteté des images observées aux différentes phases ne m'a laissé aucun doute sur sa réalité. Il ne peut d'ailleurs y avoir aucune erreur sur le sens dans lequel ces phases de la métaplasie se succèdent, à partir d'un leucocyte banal.Les leucocytes sont d'abord englobés par les cellules fixes en donnant des images identiques à celles de la phagocytose ordinaire; mais ils ressortent ensuite de ces cellules et redeviennent libres, ayant acquis une morphologie nouvelle, très caractéristique; souvent ils restent quelques temps rattachés par un mince filament à la cellule d'où ils sortent. Leur noyau a subi, chez l'adulte, mais non chez l'animal très jeune, un amoindrissement; il est normalement en bâtonnet régulier mais présente souvent une fragmentation qui indique un état de dégénérescence. Pourtant la plupart des cellules en épieu possèdent des pseudopodes lamelleux très développés, qui témoignent d'une grande activité migratrice. Les différents stades de cette évolution se rencontrent avec une très grande fréquence, dans toutes les coupes de cornée, et ils sont faciles à voir; s'ils n'ont pas été remarqués jusqu'ici, cela tient uniquement à des raisons techniques.  相似文献   

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The semen results from the mixture on ejaculation of various secretions from the testicle, the genital tract and the adnex glands. It consists on a cellular phase: spermatozoa and a liquidian phase: the seminal plasma. The spermogram is the first exam to make in order to set diagnosis of male infertility. It is completed with a biochemical study of the semen to find an excretory origin to infertility. In this work, we have studied the frequences of prostatic, vesicular and epididymious anomalys, through dosage of their markers in the semen, in 146 males consulting for infertility and eventual relationships between these markers and the characteristics of the spermogram. We found out that the prostate is the most hurt portion of the genital tract in infertile males and presents a dysfunctioning in 32,26% of cases, most often resulting in an inflammatory states of this gland. The epididymious obstruction is detected in 35% of azoospermia cases. In all the cases, we found out significant statistical correlation between the semen volume and the activity of alpha 1–4 glucosidase and also the pH of the semen and the seminal citric acid. For patients having a high leucospermia we didn’t find any relationship between the leucocytes rate in the semen and the different biochemical markers. If the seminal fructose rate has no effect on the initial mobility of spermatozoa, it has a statistically significant effect on their survival. In fact, the diminution of seminal fructose coincides with a bad survival of spermatozoa, which shows the importance of this spermatic substrate on the maintaining of spermatozoa mobility.  相似文献   

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Analysis of the amino acid composition of the hemocyanins from six species of the Astacidae, belonging to the Astacinae and the Cambarinae, shows that these respiratory pigments present a great deal of homology. This slight differentiation does not allow us to reconstruct the scheme of classification of the Astacidae into two sub-families. Comparison with the hemocyanins of two terrestrial Isopods and two marine Decapods leads to a dendrogram in which two groups of species are distinguished. The former comprises the freshwater crayfishes and the Isopods, the latter includes the marine Decapods. Such a separation can be explained by the importance of the mode of life and the development of respiratory adaptations for air-breathing, independently of the taxonomic position of the studied species.  相似文献   

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Introduction

Our work was to establish the hormonal, semen and erectile profile among haemodialysed patients and to seek the impact of hormonal disturbances on erectile function and semen parameters.

Patients and methods

We conducted a cross-sectional study in haemodialysed patients in whom a semen, in parallel with hormonal analyses including FSH (follicle stimulating hormone) and testosterone. Erectile function was assessed by the study of the international index of erectile function in its French version (IIEF). Analyses of sex hormones were done by radio immunoassay and semen analyses according to WHO guidelines.

Results

Two patients had a semen analysis and a normal hormone balance; the IIEF was normal in a one patient. Azoospermic patients (16%) showed a hypergonadotrophic eugonadism. Forty percent of the patients had hypospermia without any correlation between hypospermia and hormonal values. One third of patients showed severe oligospermia associated with high levels of FSH in 77% of cases. Sperm motility and morphology were altered in 96% and 50% of the cases respectively. Hormonal analyses showed an elevated FSH (> 8.5 mUI/ml) in 40% of the cases and testosterone was decreased (< 3.2 ng/ml) in 25% of the cases.

Discussion

Semen volume was significantly decreased in patients over 30 years. Erectile function was disturbed in 73% of the patients with a mean IIEF score of 15. Several authors have shown a correlation between gonadal dysfunction and high levels of gonadotropins in men with chronic renal insufficiency, with or without testicular atrophy. In our series, testosterone was normal despite the absence of androgen. Are haemodialysis sessions effective in preserving the endocrine function?

Conclusion

Patients in chronic haemodialysis for a period exceeding one year had a hypergonadotrophic eugonadism and a severe erectile dysfunction. The state of the genital tract was relatively preserved. The duration of haemodialysis did not significantly affect sperm and erectile function. Patients older than 30 years showed a significant decrease in semen volume, which could be a marker to determine the impairment of erectile and reproductive functions.  相似文献   

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Summary Sandy clay loam soils in the La Roche-Posay area, and the different parts ofTrifolium repens growing on 9 locations, were analyzed for their contents of selenium and 16 other elements. The level of K, P, Se in the young leaves was 2 or 3 times higher than in the old organs. The roots showed the lowest contents for these three elements. By contrast, their content of Al, Fe, As were 10 times higher than in the young leaves. When the content of Se in leaves and roots was low, the contents of P, Al and Fe increased with increasing contents of Se. When the level of Se was high, the reverse was the case.   相似文献   

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