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1.
2.
《Comptes Rendus Palevol》2002,1(2):111-116
The new rich vertebrates deposit from the Lower Oligocene, at Vayres-sur-Essonne (Essonne, France), contains 34 marine and seven continental taxa, 17 taxa being recorded for the first time from the Paris Basin. The richness of the ichtyofauna is higher than in anyone of the Parisian Oligocene deposits and equals the one of the ‘Argiles de Boom’ (Belgian Rupelian). Its affinities with the septentrional ichtyofauna is confirmed, meridional elements being rare. The terrestrial fauna, the oldest known from stratotypical Stampian (base of the Upper Stampian) shares affinities with the one of Montalbán and attests the occurrence of nearly freshwater environments. To cite this article: D. Merle et al., C. R. Palevol 1 (2002) 111–116.  相似文献   

3.
The earliest vertebrates and the first steps of the evolution of the skull. Vertebrates are one of the few metazoan taxa, which display a well-corroborated phylogenetic pattern, a good and anatomically informative fossil record, and a relatively slow ontogenetic development. They are thus a favourite taxon for illustrating evolution as a historical process, although the stem of the vertebrate tree remains poorly documented by fossils, except for some Early Cambrian forms. Therefore, the characterization of the vertebrates now rests essentially on a small number of developmental characters, mostly involved in the rise of the skull, and whose precursors may occur in other chordates. The tree of the crown-group vertebrates also shows some major morphological gaps due to early extinctions, but a number of Palaeozoic stem gnathostome taxa helps in documenting the agnathan-gnathostome evolutionary transition. However, stem cyclostomes remain elusive.  相似文献   

4.
The ostracod fauna collected from the Cherahil formation that crops out at the Jebel Serj section (central Tunisia) contains 24 species belonging to 12 genera. These ostracods are associated with 9 genera of benthic Foraminifera (including 4 Nummulites species) and 7 genera of planktonic Foraminifera. The biostratigraphic study of ostracod assemblages results to the recognition of 6 biozones which are correlated with Lutetian-Priabonian. The Shannon Weaver, Margalef and equitability indices point to internal platform netritic conditions, with minor fluctuations in depth and oxygenation. The palaeobiogeographic distribution of ostracod species found in the study area of Central of Tunisia establishes a good connexion with the basins developed in Northern Africa (Tunisia, Algeria, Libya and Mauritania) and the Middle East (Egypt and Jordan).  相似文献   

5.
Prostasomes are particular lipid vesicles secreted by the human prostate and found in the semen. No specific action has yet been attributed to prostasomes, but they appear to act at various levels. For example, prostasomes enhance sperm motility in vitro and participate in the immunomodulation properties of seminal plasma. Excessive production of reactive oxygen species (ROS) in human semen has a negative influence on the functional capacities of spermatozoa. The presence of leukocytes in semen is associated with increased production of ROS that can be harmful to sperm cells, under certain conditions. Previous results tend to suggest a possible role of prostasomes on ROS production in human semen. After reviewing the literature concerning the structural and functional characteristics of prostasomes and the role of ROS in human semen, we report our results concerning the influence of prostasomes on ROS production and the consequences on semen. We have demonstrated that prostasomes exert an antioxidant function in human semen. This function is effective both on polymorphonuclear neutrophils and on sperm cells. The mechanism of action of prostasomes is unusual, as they act on ROS production mainly on the plasma membranes of neutrophils. They induce a decrease of NADPH-oxidase activity associated with rigidification of the plasma membrane. Prostasomes protect the functional capacities of spermatozoa during an oxidative stress created by the presence of NADPH in the incubation medium.  相似文献   

6.
Philippe Huneman 《PSN》2004,2(2):47-60
The author analysesEncyclopédie’s articles devoted to nervous and mental functioning and disorders, showing that a new approach to lunacy as a mental illness, which is defined in some articles as a “general trouble of the animal economy”, progressively emerged. The term,animal economy, unified physical and moral aspects of the study of man. It was elaborated by XVIIIth century physiologists and was widely accepted by French physicians. This idea is based on the vitalistic thought of the Montpellier school, which equated life with sensibility, and on English medical conceptions of a nervous-centred organism. Later on Philippe Pinel’s work displayed the legacy of these conceptions. On one hand, the comprehensive view of physical and moral dimensions in theanimal economy neutralized the question of an organic or psychogenetic origin of madness. This enabled him to consider it as a determinate field of sensibility interactions and as a medical matter, and to legitimize the group of therapeutic practices that he namedtraitement moral. On the other hand, Pinel departed from the classical conception ofanimal economy by developing his concept of aprinciple of mania, which underlies the manifold symptoms and forms of madness, and which are only perceptible to a trained specialist (aliéniste). The historical development analysed in this article show how alienists were enabled to claim both the wholly medical nature of insanity as disease, and their specific competence as apart from the other medical disciplines. To this extent, Esquirol achieved Pinel’s scientific work.  相似文献   

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8.
《Comptes Rendus Palevol》2005,4(5):405-412
A new fish-bearing Miocene site, south of the ‘Chaîne des Chotts’ (southern Tunisia). Palaeoenvironment and palaeobiogeography. A systematic excavation in the Miocene continental sands of the Béglia Formation (southwestern Tunisia), south of the ‘Chaîne des Chotts’, yielded a rich fossil-fish assemblage. These sands, with soft rollers and oblique stratifications are in unconformity on the Cretaceous and are covered by Miocene clays. The organisation and the nature of the facies, as well as the palaeocurrent figures testify to a proximal fluvial-deltaic regime. It is SW–NE prograding. The three fish taxa (polypterid, clariid, latid) are typical of modern Nilo-Sudanese assemblages, but are absent from Maghreb. The regional palaeobiogeographic relations are discussed. To cite this article: B. Mannaï-Tayech, O. Otero, C. R. Palevol 4 (2005).  相似文献   

9.

Obiective

To describe a case of seminoma occurring in a patient with a past history of cryptorchidism, infertility and clomiphene citrate (CC) treatment. To review the literature of seminoma in association with these risk factors.

Case report

A 33 year old man developed typical seminoma in the right testis. A bilateral cryptorchidism was lately diagnosed and treated by orchidopexy at the age of 17. Primary infertility due to oligoasthenospermia was diagnosed at the age of 29. Treatment was initiated with CC at the dose of 25 mG/day. Semen quality improved gradually. After failure of various assisted reproductive techniques, a spontaneous pregnancy was achieved and a healthy baby delivered. Shortly after delivery the seminoma was diagnosed, after a totla of three years of treatment. Six cases of testicular tumors have been reported in the literature in which patients had been pretreated with fertility drugs for various priods of time before tumors was diagnosed. Cryptorchidism is a well-known risk factor for testicular malignancy, as is the infertil state. Clomiphene citrate may promote malignant transformation by activation of estrogen receptors, by raising gonadotropin and/or testosterone concentrations, or by other mechanisms.

Conclusion

Clomiphene citrate may have a previously unappreciated malignancy-promoting effect in infertile men, especially those with other risk factors. Clinicians treating similar patients should take this into account and the literature monitored for other associated cases.  相似文献   

10.
Osteogenesis imperfecta is a genetic disease characterized by bone frailty. It is generally caused by an abnormal production of collagen, which is the main fibrous protein of the bone. Collagen is also present in the skin, tendons, the sclera of the eye and dentin. The most frequent manifestation of osteogenesis imperfecta is the occurrence of multiple fractures without major trauma. Severity and timing of the attack varies widely: some patients sustain a significant number of fractures during early childhood which may have a serious impact on growth, while others will have some fractures separated by a few years. In all cases, the bone strength improves in adulthood. The bone fractures cause pain and bone deformities sometimes result in a smaller size. Scoliosis is frequent and associated with painful vertebral collapses. We present a case of osteogenesis imperfecta in a 40-year-old adult and we describe the various orthopaedic complications of the disease, stressing the role of bone scintigraphy in the diagnosis and monitoring of these complications.  相似文献   

11.
In recent years, we have witnessed an international debate about the question of the origins of art. On the one hand, some specialists have suggested that art appeared for the first time at the beginning of the Upper Paleolithic associated to the emergence of Homo sapiens sapiens. From this point of view, Paleolithic art as well as other hallmarks of behavioral modernity were exclusive to anatomically modern humans. On the other hand, some scholars have put into question the traditional paradigm concerning the origins of art and have suggested that artistic objects arose over a long period of time among different species, including Neanderthals. In order to contextualize this debate, we analyze in this article the history of the different interpretations and controversies concerning the question of the origins of art. Taking as reference the French case, we examine the connections between the different theories about art's origins suggested by Pleistocene art specialists during the last century and the dominant paradigms in human paleontology during the same period. Informed by one another, the question of the origins of art and that of human evolution seems to be inextricable linked.  相似文献   

12.
The origin and evolution of birds: 35 years of progress. Birds are dinosaurs – specifically, small feathered and flighted theropod dinosaurs that probably originated in Laurasia during the Late Jurassic over 140 million years ago. They are most closely related to other small theropods such as dromaeosaurs and troodontids, terrestrial predators that were fleet-footed hunters. The origin of birds is a classic example of two kinds of macroevolution: the phylogenetic origin of the group, and the sequential assembly of adaptations such as flight that are indelibly associated with birds. These adaptations were not assembled all at once. Rather, a great many characteristics associated with birds and flight first appeared in non-avian dinosaurs, where they were used for many purposes other than flight. These included insulation, brooding, and probably display and species recognition. Birds diversified steadily but gradually after their origin, which is identified with the origin of flight (Archaeopteryx); forelimb and other flight-associated features evolved more rapidly than features associated with the posterior skeleton. The first birds grew more slowly than extant birds do, and more like other small Mesozoic dinosaurs; like them, they probably matured sexually well before they completed their active skeletal growth. The origin of flight is not a problem of “trees down” or “ground up,” but rather an examination of the order in which diagnostic flight characters evolved, and what each stage can reveal about the functions and habits of bird outgroups at those evolutionary junctures.  相似文献   

13.
14.

Objective

To assess the efficacy and safety of percutaneous testicular biopsy to provide sperm cells for ICSI in male patients with azoospermia not amenable to surgical treatment.

Materials and methods

From October 1995 to December 2001, 175 biopsies were performed in men with azoospermia to provide material for intracytoplasmic sperm injection. Azoospermia was obstructive (OA) in 41 cases and non-obstructive (NOA) in 134 cases. Open biopsy was performed in the first 15 patients in the series and percutaneous biopsy was performed on an outpatient basis, under local anesthesia, with a Biopty Gun® (14G needle), in the subsequent patients as the first step in management. Open surgical biopsies were performed in another 15 patients following a sperm cell-negative percutaneous biopsy.

Results

All biopsies performed for OA were positive, but only 51/134 biopsies (38%) were positive in the NOA group. The material provided by percutaneous biopsy, when positive for sperm cells, was always sufficient to perform ICSI. When percutaneous biopsy was negative, open surgical biopsy failed to give better results. Five men developed minor complications (acute hematocele) following percutaneous biopsies requiring reoperation for hemostasis (3.12%). No major complications were observed. Results were comparable in terms of fertilization and pregnancy rates whether fresh or frozen-thawed sperm was used.

Conclusion

Percutaneous testicular sperm extraction is a safe, well-tolerated and cost-effective procedure in the management of male-factor infertility related to azoospermia.  相似文献   

15.
《L'Anthropologie》2017,121(4):300-311
The present paper is devoted to the study of Paleolithic settlements recently discovered in the territory of the Djizak Oasis. Some Paleolithic settlements such as Yangikichlak, Azimboulak, Gourdara 1, 2 and Shachmai-Doston were discovered at the roof of the Nourata mountain range in the Farich district. Their cultural layers are not conserved but the single discoveries testify to the presence of prehistoric human camps in the Upper Paleolithic period. The lithic assemblage from the sites of the Djizak Oasis has some similarities with the material coming from the Tachkent site complex and from the Samarkand drainage basin. The discovery of the settlements and their later studies fill gaps on the Paleolithic map of the region.  相似文献   

16.
The impact of oestrogens on the male reproductive system remains the subject of intensive research activity and debate. Oestrogen action is mediated via high affinity intracellular receptors expressed in target tissues. Two subtypes of oestrogen receptor known as REα (NR3A1) and ERß (NR3A2) have been cloned and hERß variant isoforms identified. In target cells these receptors can exist as homo- or heterodimers. We have used immunohistochemistry to examine the patterns of expression of ERs in human and non-human primates as a first step in determining the cellular targets for oestrogen action in the male. REα was detected in the epithelial cells of efferent ductules (ED) occasionally in epithelial and stromal cells within the epididymis but was undetectable in human or primate testes. Using a polyclonal antibody raised against the hinge domain of ERß, immunopositive staining was detected in multiple cell types within the testis and in epithelial and stromal cell nuclei throughout the male reproductive system (ED, epididymis, vas deferens, seminal vesicles, prostate) and in the bladder. We have also used monoclonal antibodies that distinguish between wild type, full-length ERß (ERß1), and a splice variant isoform called ERßcx/ERß2 that does not bind oestrogens. ERß1 and ERß2 proteins were both detected in human testis and have distinct but overlapping patterns of expression. ERß1 was also detected in ED, epididymis and vas. In conclusion, oestrogen receptors are widely expressed in the male urogenital system and with the exception of the ED there are more cells that express ERß than REα. In the adult human the testicular cells most likely to be targets for oestrogens are round spermatids in which levels of expression of full-length wild type receptor (ERß1) are high.  相似文献   

17.
《Geobios》1986,19(3):335-356
After a short historical introduction, the principal notions used to study the connections between ontogeny and phylogeny are desribed. The three fondamental standards (shape, age, size) upon which are made ontogenetic comparisons are defined and discussed.The different ontogenetic heterochronies are described and illustrated with concrete paleontological examples. Successively are studied:u
  1. -dwarfirsm and giantism which are particularcases;
  2. -the 4 types of heterochrony which affect somatic development (neoteny and acceleration) or sexual maturation (hypermorphosis and progenesis);
  3. -the innovations which are a fast appearence of a new character and their associations with the 4 elementary heterochronies.
The heterochronies are connected with phylogeny. This leads to the definition of two fondamental tendancies: paedomorphosis and peramorphosis; the terms proterogenesis and palingenesis are redefined. To conclude, this study is inserted in a more wider context that shows the importance of ontogenetic knowledge to understand numerous evolutif processes (tempos in evolution, demographic strategies, cladism).  相似文献   

18.
19.
La Garma Cave is an Upper Palaeolithic site located ca 15 km from Santander (Cantabria, Spain). The lower gallery, which is accessible thanks to two wells, keeps paintings on the walls and numerous objects laying on the floor, objects made in bone or antler which are carved, engraved and painted. The analysis of more than 50 samples taken from the walls or the objects (37 red, 11 black, five yellow, two brown, one purple) takes part in the global project of the “chaîne opératoire” comprehension of the prehistoric painting activity. The analysis is aimed also to understand the organisation of La Garma cave, looking for the various steps of the decoration of the different rooms. The results bring to light the modulated realisation of the wall paintings: few figures were painted rapidly without any specific intention, the majority, on the other hand, were realised after a complex preparation of the painting matter with the use of specific paint pots.  相似文献   

20.
《L'Anthropologie》2016,120(5):588-609
The study of graphic convergences and divergences in Palaeolithic art is used to understand the culture, territories and interaction systems of human groups. La Covaciella cave has fifteen animal representations and other linear, dots and geometric motifs. The bison stands out; some were executed with complex technical procedures. Two of them were dated by C14 AMS, obtaining a result of 14,260 ± 130 BP (17,733–16,973 cal BP) and 14,060 ± 140 BP (17,503–16,260 cal BP). These correspond chronologically with the beginning of the middle Magdalenian or the very end of the lower Magdalenian. Similar depictions to the bison at La Covaciella are located in other areas of Western Europe. The repertoire of parietal bison displaying graphic similarities with those at La Covaciella is very large; both of the Pyrenean model (Niaux morphotype) and of the Perigordian model (Font-de-Gaume morphotype). A first consideration derived from the search for comparisons involves a new interpretation of the territorial value implied by the term Pyrenean style (Asturias, Cantabria, Basque Country, Navarre, Pyrénées-Atlantiques, Hautes-Pyrénées, Haute-Garonne, Ariège, Dordogne, Lot, Ardèche and Vienne). The Font-de-Gaume parietal morphotype is most common in Dordogne. In addition, in some cases, spatial complementariness has been found, with both graphic morphotypes. This article proposes different chronological and anthropological hypothesis to explain the distribution and coexistence of the two graphic models.  相似文献   

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