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11.
报道无患子科(Sapindaceae)3个单种属植物的染色体数目,其中掌叶木属和茶条木属为首次报道。掌叶木属(Handeliodendron Rehd.)、茶条木属(Delayaya Franch.)、伞花木属(Eurycorymbus Hand.-Mazz.)植物的染色体数目分别为2n=40,28和26,且它们的染色体皆为小染色体。  相似文献   
12.
The caatinga semi-arid ecosystem of northeastern Brazil is characterized by a dry, spiny and predominantly deciduous shrub/forest vegetation, and many species there are potential sources of renewable resources for the oleochemical industry. The present research determined the oil content and fatty acid profiles of seeds from eight caatinga species. Seed oils were extracted in a Soxhlet system, and their fatty acid content identified by GC–MS. Oil content varied between 20.2% in Tabebuia impetiginosa (Mart.) Standl. (Bignoniaceae) and 46.4% in Barnebya harleyi (W.R. Anderson & B. Gates) Malpighiaceae. Anemopaegma laeve DC. (Bignoniaceae) had the highest oleic acid content (63.4%), while high levels of linoleic acid were found in Banisteriopsis pubipetala (Juss.) Cuatrec. (42.8%) and B. harleyi (31.9%) (both Malpighiaceae). Palmitic acid was the major fatty acid (50%) in Hippocratea volubilis (L.) (Celastraceae). High levels of linoleic and linolenic acids were found in Croton adamantinus Mull. Arg. (Euphorbiaceae), averaging 44.2% and 45.2% respectively. Gadoleic acid in was the most abundant fatty acid in the oil produced by Serjania lethalis A. St. Hill. (Sapindaceae), averaging 69.6%. B. pubipetala, B. harleyi, C. adamantinus, and H. volubilis were identified as promising species for cultivation.  相似文献   
13.
The floral organogenesis and development of Delavaya toxocarpa Franch. (Sapindaceae) were studied under scanning electron microscope and light microscope to determine its systematic position within Sapindaceae. Flowers arise in terminal thyrses. The sepal primordia initiate in a spiral (2/5) sequence, which are not synchronous. The five petal primordia initiate almost synchronously and alternate with sepal primordia. Eight stamens initiate almost simultaneously and their differentiation precedes that of the petals. The last formed petal and one stamen initiate from a common primordium. Mature stamens curve inwards and cover the ovary in bud. The gynoecium begins as a hemispheric primordium on which two carpellary lobes arise simultaneously. Later in development a single gynocium is formed with two locules and two ovules per locule. Floral morphology suggests a closer affinity with Sapindaceae, although certain features of floral ontogenesis are similar to those observed in certain members of the former Hippocastanaceae, such as Handeliodendron.  相似文献   
14.
Rambutan is a popular tropical fruit known for its exotic appearance, has long flexible spines on shells, extraordinary aril growth, desirable nutrition, and a favorable taste. The genome of an elite rambutan cultivar Baoyan 7 was assembled into 328 Mb in 16 pseudo-chromosomes. Comparative genomics analysis between rambutan and lychee revealed that rambutan chromosomes 8 and 12 are collinear with lychee chromosome 1, which resulted in a chromosome fission event in rambutan (n = 16) or a fusion event in lychee (n = 15) after their divergence from a common ancestor 15.7 million years ago. Root development genes played a crucial role in spine development, such as endoplasmic reticulum pathway genes, jasmonic acid response genes, vascular bundle development genes, and K+ transport genes. Aril development was regulated by D-class genes (STK and SHP1), plant hormone and phenylpropanoid biosynthesis genes, and sugar metabolism genes. The lower rate of male sterility of hermaphroditic flowers appears to be regulated by MYB24. Population genomic analyses revealed genes in selective sweeps during domestication that are related to fruit morphology and environment stress response. These findings enhance our understanding of spine and aril development and provide genomic resources for rambutan improvement.  相似文献   
15.
A new species ofSerjania (S.lancistipula) from Bahia belonging to theS. paradoxa group is described and illustrated. A key to the species in theparadoxa group is provided.  相似文献   
16.
New chromosome counts for 9 species and 2 genera of Sapindaceae are presented and compared with a review of all available chromosome numbers of the family. In 4 species diploid numbers differing from previous reports are found. In 4 species of the tribe Paullinieae (S. diversiflora, S. subdentata, C. grandiflorum and C. halicacabum) detailed studies on interphase nucleus structure, condensing behaviour and chromosome banding patterns are presented. The karyological differentiation of Paullinieae is generally characterized by dysploid reduction of chromosome numbers and the increase of chromosome size. Sequential staining of nuclei with CMA/DAPI and Giemsa-C-banding demonstrates diversification of constitutive heterochromatin (= hc) and different types of chromatin organization in Serjania and Cardiospermum. The obvious lack of polyploid series and the karyological evolution within the family is discussed. The outstanding small genome size found in Cardiospermum halicacabum is considered to be due to a secondary loss of DNA in the course of the change to herbaceous growth.  相似文献   
17.
Threonine and C1 units from methionine contribute to form an intermediate in the biosynthesis of l-β-(methylenecyclopropyl)-alanine, the toxi  相似文献   
18.
The methanolic extract from the pericarps of Sapindus rarak DC. was found to show pancreatic lipase inhibitory activity (IC50 = ca. 614 μg/mL). From the extract, oleanane-type triterpene oligoglycosides, rarasaponins I–III (13), and raraoside A (4), were isolated together with 13 known saponins and four known sesquiterpene glycosides. Among them, several saponin constituents including rarasaponins I (1, IC50 = 131 μM) and II (2, 172 μM), and raraoside A (4, 151 μM) inhibited pancreatic lipase activity, which were stronger than that of theasaponin E1 (270 μM).  相似文献   
19.
A simple, rapid and efficient protocol for micropropagation of Cardiospermum halicacabum via axillary bud multiplication has been successfully developed. The organogenic competence of nodal segments was investigated on Murashige and Skoog (MS) medium supplemented with different concentrations of benzyladenine (BA), kinetin (Kn), thidiazuron (TDZ) and 2-isopentenyladenine (2-iP). Multiple shoots differentiated directly without callus mediation within 4 weeks when explants were cultured on a medium fortified with cytokinins. The maximum number of shoots (14.83 ± 0.52) was developed on a medium supplemented with 0.3 μM TDZ. Such proliferating shoots when subcultured onto MS media devoid of TDZ gave the highest rate of shoot multiplication (35.66 ± 1.00) by the end of fourth subculture passage. Elongated shoots were rooted on 1/3 MS medium augmented with 0.5 μM IAA. The plantlets thus obtained were successfully hardened and transferred to greenhouse.  相似文献   
20.
Rambutan (Nephelium lappaceum) and lychee (Litchi chinensis) are tropical trees in the Sapindaceae that produce delicious edible fruits and are increasingly cultivated in tropical regions. These trees are afflicted with a stem canker disease associated with the ascomycete Dolabra nepheliae. Previously known from Asia and Australia, this fungus was recently reported from Hawaii and Puerto Rico. The sexual and asexual states of Dolabra nepheliae are redescribed and illustrated. In addition, the ITS and large subunit of the nuclear ribosomal DNA plus fragments from the genes RPB2, TEF1, and the mitochondrial small ribosomal subunit were sequenced for three isolates of D. nepheliae and compared with other sequences of ascomycetes. It was determined that D. nepheliae represents a new lineage within the Eurotiomycetes allied with Phaeomoniella chlamydospora, the causal agent of Petri grapevine decline.  相似文献   
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