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Cedrus libani, the cedar of Lebanon, is a threatened conifer native to the Levant. Over 4000 years of exploitation have resulted in the fragmentation and degradation of the Lebanese cedar populations. Continued urban and agricultural development in Lebanon adds to the difficulty of effective conservation. Two protected areas have recently been established which contain two of the more important forests: a cedar dominated forest in the Shouf region and a mixed forest at Ehden. A number of other populations are protected by ministerial decrees, and there is a need for rigorous management of all the remaining populations. The application of in vitro techniques such as somatic embryogenesis may assist in the conservation of this species. We have produced somatic pro-embryos using immature zygotic tissue as explants cultured on half-strength MS medium containing an auxin and a cytokinin (10 M 2,4-D and 5 M BAP). The application of somatic embryogenesis to the Lebanese cedar would be in the propagation and preservation of selected genotypes, either those from old growth provenance for use in restoration, or those with desirable commercial or horticultural characteristics.  相似文献   
3.
The diversity of arthropods is studied, at family and species level, on a pig carcass during a warm season in an open field in Badghan-Mount Lebanon. Ten orders of arthropods were found associated to the carcass. A total of 1168 specimens of adults Diptera and Coleoptera were collected. Among Diptera, the predator Chrysomya albiceps was dominant on the carcass during the active decay stage and Musca spp. were necrophagous. Within Coleoptera, Creophilus maxillosus (Linnaeus, 1758), Philonthus concinnus (Gravenhorst, 1802), Aleochara lata Gravenhorst, 1802, and Saprinus sp. were the predator taxa. Dermestes frischii Kugelann, 1792 and Necrobia rufipes (De Geer, 1775) were more present during the advanced decay, together with anthicids. In addition to a list of species visiting the carcass, we carried out a multivariate analysis of principal components to explore the relationships between the pattern of presences of 16 insect families and the four decomposition stages during the first 30 days of the carcass decomposition. The groupings of insects during the four decomposition stages show significant dissimilarities, suggesting that the different stages are characterized by different insect associations, as reported in many other previous studies.

Résumé. La succession des communautés d’arthropodes sur une carcasse de porc au Liban : approches à divers niveaux taxonomiques et notes faunistiques. La diversité des arthropodes est étudiée, au rang familial et spécifique, sur une carcasse de porc pendant la saison chaude en milieu naturel, sur le site de Badghan-Mount, au Liban. Dix ordres d’arthropodes ont été trouvés associés à la carcasse. Un total de 1168 spécimens adultes de Diptères et de Coléoptères a été collecté. Parmi les Diptères, le prédateur Chrysomya albiceps était dominant sur la carcasse au stade de décomposition active. Les Musca spp. étaient nécrophages. Parmi les Coléoptères, Creophilus maxillosus (Linnaeus, 1758), Philonthus concinnus (Gravenhorst, 1802), Aleochara lata Gravenhorst, 1802 et Saprinus sp. étaient prédateurs. Dermestes frischii Kugelann, 1792 et Necrobia rufipes (De Geer, 1775) et les Anthicidae étaient plus présents pendant la décomposition avancée. En complément à la liste des espèces visitant la carcasse, nous avons effectué une analyse multivariée en composantes principales pour explorer les relations entre le patron de présence de 16 familles d’insectes et les quatre stades de décomposition au cours des 30 premiers jours de la décomposition. Les groupements d’insectes montrent des dissimilarités significatives, ce qui suggère que les différents stades sont caractérisés par des associations différentes d’insectes, de façon analogue à ce qui a été rapporté dans plusieurs études antérieures.  相似文献   

4.
Larvae of the cedar web-spinning sawfly, Cephalcia tannourinensis Chevin (Hymenoptera: Pamphiliidae), infected with a white fungus were collected from the Tannourine-Hadath El-Jebbeh cedar forest. Macro- and micro-morphological data based on the examination of colonies, conidiophores, and conidial shape of the fungus suggested a Beauveria species. Sequence analysis of the internal transcribed spacer regions of the isolated fungus showed that it is most closely related to isolates of B. bassiana Clade C. The present study showed that the isolated B. bassiana is a naturally occurring entomopathogenic fungus parasitizing the larvae of C. tannourinensis in Lebanon. Laboratory bioassays showed that B. bassiana caused high mortality of eggs and larvae. The infected eggs turned brownish in color, while larvae of the first instar ceased feeding and showed immobility and rigidity within 5 days and before sporulating conidial mat appeared on their cuticle. Second and third larval instars took longer time to show fungal sporulation: mortalities ranged between 85 and 100% within 7 days when treated with different conidial concentrations. The efficacy of control of C. tannourinensis using B. bassiana was higher or equal to the reference insect growth regulator, diflubenzuron, suggesting the possibility of its success as a biological control agent.  相似文献   
5.
Weight‐length relationships (WLRs) were estimated for 3 demersal species, from the Lebanese marine waters, eastern Mediterranean, namely Coelorinchus caelorhincus (Risso, 1810), Scorpaena elongata Cadenat, 1943 and Stephanolepsis diaspros Fraser‐Brunner, 1940. The specimens were collected using trammel and gill nets from June 2012 to October 2014. The values of parameter b of the WLRs aLb ranged from 2.922 to 3.708. Pronounced sexual dimorphism in WLR was observed for S. diaspros and none showed a WLR‐based geographical pattern of distribution. WLRs reported in this study should be applied only within the observed length ranges.  相似文献   
6.
This study focuses on the population biology of the common guitarfish Rhinobatos rhinobatos, a cartilaginous fish listed as Endangered in the International Union for the Conservation of Nature (IUCN) Red List. Between December 2012 and January 2014, 67 individuals were collected by bottom longlining in coastal Lebanese marine waters at different ports at depths ranging from 10 to 110 m. The total length (LT) of the specimens ranged from 50 to 143 cm, and the mean ± s.d . was 76·2 ± 19·7 cm. The most common LT classes were between 60 and 70 cm. The total mass of the specimens ranged from 410 to 10 000 g, and the mean ± s.d . was 1841 ± 1987 g. A total of 34 males and 33 females were collected, and the sex ratio was not significantly different from 1:1. The mass and LT relationship showed positive allometric growth (b = 3·096 and r2 = 0·99), and the mean ± s.d . LT at which 50% of the individuals were sexually mature was 84·73 ± 5·81 cm for females and 78·57 ± 4·88 cm for males. The gonado‐somatic and hepato‐somatic indices were determined along with a condition factor, and parturition appeared to occur in winter. The primary prey items found in the fish stomachs during the autumn and winter seasons were Penaeidae. The results of this study will help to parameterize models of the population dynamics for this exploited fish stock to ensure the long‐term sustainability of its fishery.  相似文献   
7.
J. G. Shiber 《Hydrobiologia》1981,83(3):465-476
Samples of the edible tissue of cephalopod molluscs (cuttlefish, squid, octopus) and crustaceans (lobster, shrimp) collected off the coast of Lebanon were found to concentrate similar levels of cadmium, copper, nickel, and chromium. Lead and zinc were highest in the cephalopods and iron was highest in the crustaceans.The molluscs collected from Beirut had higher levels of many metals than those taken from the other locations. The Beirut octopus had higher lead, cadmium, copper, iron, and chromium. Lead, cadmium, and copper were also highest in the Beirut cuttlefish while iron and zinc were elevated. The crustaceans from Beirut showed no strong tendency to concentrate higher metal levels, except for the Beirut lobster which had higher copper than the other samples.In the cuttlefish, the analysis of bone showed generally higher cadmium, zinc, nickel, and chromium but lower copper and iron than the muscle. However, at Beirut, the bone samples had much higher iron. Levels of most metals in the exoskeletons of the lobster and shrimp were quite similar to those in the muscle tissue with the exception of iron in the lobster which was highest in the exoskeleton, and zinc in both crustaceans, which was more highly concentrated in the muscle.  相似文献   
8.
N. J. Alouf 《Hydrobiologia》1986,133(1):45-57
The biology of a population of Gammarus laticoxalis laticoxalis living in a perennial, relatively constant temperature river in Lebanon is studied. Life cycle, fecundity, sex-ratio, body length and demography were followed for almost two years. The reproductive cycle shows no resting period with fecundity being highest during the rainy season as compared to dry summer months.
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9.
In the Sunni Muslim world, religious mandates prohibit both adoption and gamete donation as solutions to infertility, including in the aftermath of in vitro fertilization (IVF) failures. However, both of these options are now available in two Middle Eastern countries with significant Shi'ite Muslim populations (Iran and Lebanon). On the basis of fieldwork in multisectarian Lebanon, I examine in this article attitudes toward both adoption and gamete donation among childless Muslim men who are undertaking IVF with their wives. No matter the religious sect, most Muslim men in Lebanon continue to resist both adoption and gamete donation, arguing that such a child "won't be my son". However, against all odds, some Muslim men are considering and undertaking these alternatives to family formation as ways to preserve their loving marriages, satisfy their fatherhood desires, and challenge religious dictates, which they view as out of step with new developments in science and technology. Thus, in this article I examine the complicated intersections of religion, technology, marriage, and parenthood in a part of the world that is both poorly understood and negatively stereotyped, particularly in the aftermath of September 11, 2001.  相似文献   
10.
Abstract:  Three previously unknown octopods are described from Upper Cenomanian limestones of the Hâqel and Hâdjoula localities (Lebanon). Keuppia levante gen. nov., sp. nov., Keuppia hyperbolaris gen. nov,. sp. nov. and Styletoctopus annae gen. nov, . sp. nov. are regarded as the earliest representatives of the Octopoda (= Incirrata). This assumption is mainly based on their medially isolated bipartite gladius vestige. As can be inferred from growth increments, Keuppia gen. nov. can be distinguished from the genus Palaeoctopus by blades that grow forwards along their longitudinal axis. The gladius vestige of Keuppia hyperbolaris sp. nov. differs from that of Keuppia levante sp. nov. in having a more heterogeneous course of growth lines. Based on a pair of widely separated stylets, which closely resemble the rods of modern octopods, Styletoctopus annae gen. nov., sp. nov. is assigned to the Recent family Octopodidae. Peculiar encrustations, which are situated in close association with the gladius vestiges of Keuppia levante sp. nov., Keuppia hyperbolaris sp. nov., and Styletoctopus annae sp. nov. are interpreted as basal fin cartilages. The gladius vestige morphology of Keuppia hyperbolaris sp. nov. and Keuppia levante sp. nov. opens the possibility that both the Octopda and the Cirroctopoda originated from loligosepiid vampyropods instead of teudopseid. The surprising existence of a stylet-like gladius vestige in Styletoctopus annae sp. nov. suggests that the octopod clade branched off much earlier than previously believed. Octopod apomorphies such as the development of stylets, loss of fins and cirri must have been occurred before the Cenomanian.  相似文献   
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