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1.
Dipterocarpaceae is the dominant family of Southeast Asia's climax tropical rain forest region, and it contains the region's most important commercial timber species. A molecular phylogeny of the Dipterocarpaceae subfamily Dipterocapoideae was constructed using restriction fragment length polymorphisms of polymerase chain reaction-amplified specific genes in chloroplast DNA. A total of 141 site changes were detected among ten genera and 30 species in 11 different genes: rbcL, psbA, psbD, rpoB, rpoC, petB, atpH, 16S, psaA, petA and trnK. Phylogenetic trees constructed by Wanger parsimony and neighbor-joining methods, using Upuna as the outgroup, displayed five monophytelic groups that included Upuna: HopeaShorea-Parashorea-Neobalanocarpus; Dryobalanops; Dipterocarpus; Anisoptera-Vatica-Cotylelobium; and Upuna. The phylogenetic trees clearly separate species with two different base chromosome numbers: the first group is x=7, and the other is x=11. The x=7 group is thought to be in a synapomorphic character state. Parashorea lucida is a sister to most Shorea species. Neobalanocarpus heimii and Hopea from a clade of a sister to two Shorea species, and Cotylelobium and Vatica are closely related species. Our conclusions agree with a phylogeny derived from wood anatomy data analysis, and with Symington's and Ashton's taxonomic classifications.The raw data of the PCR-RFLP analysis can be obtained from the authors  相似文献   
2.
    
Within their natural distribution ranges, plant species exhibit a genetic structure that has been created by global climate change and natural selection over long periods. This genetic structure needs to be conserved for sustainable use of genetic resources. To conserve local forests with different genetic structures, genetic guidelines for seed and seedling transfer in individual species are necessary. Genetic guidelines have been published for 43 Japanese tree species using population genetic data; however, for practical use, more detailed genetic borders between important genetic lineages should be clarified to inform seed collection and planting. Thus, we investigated in detail the genetic borders between two important Japanese oak species, Quercus serrata and Quercus crispula, in the Chubu region of Japan using chloroplast and nuclear DNA markers, and we discuss the factors that influenced border creation using the results of species distribution modeling (SDM). The chloroplast DNA (cpDNA) haplotype was clearly different within the Chubu region of Japan but the difference in nuclear DNA between northern and southern haplotype populations was very small, both in Q. serrata and Q. crispula. The results of SDM showed that during the last glacial maximum (LGM) Q. serrata was distributed mostly along the coastline but Q. crispula was distributed not only along the coast but also in mountainous areas further inland. The cpDNA genetic borders of these two oak species are complex and seem to have been influenced by topography and their distribution during the LGM. We propose and discuss genetic guidelines for these two oak species based on the results of this study.  相似文献   
3.
The sequence divergence of chloroplast rbcL, matK, trnV intron, and rpl20-rps18 spacer regions was analyzed among 32 Pinus species and representatives of six other genera in Pinaceae. The total aligned sequence length is 3570 bp. Of the four sequences examined, matK evolved much faster than rbcL in Pinus and in other Pinaceae genera. The two noncoding regions did not show more divergence than the two coding regions, especially within each Pinus subgenus. Phylogenetic analyses based on these four sequences gave consistent results and strongly supported the monophyly hypothesis for the genus Pinus and its two recognized subgenera. Pinus krempfii, the two-flat-needle pine endemic to Vietnam, was placed in subgen. Strobus and showed closer affinity to subsect. Gerardianae. The ancient character of sect. Parrya is further confirmed. However, monophyly of the sect. Parrya is not supported by our data. Among the Eurasian pines of subgen. Pinus, Mediterranean pines formed one clade and the Asian members of subsect. Sylvestres formed another. The Himalayan P. roxburghii showed considerable divergence from all the other hard pines from both regions. Pinus merkusii was distinctly separated from all the Asian members of subsect. Sylvestres. The implications of our results for Pinus classification are discussed.  相似文献   
4.
The number of people in Japan suffering from Cryptomeria japonica pollinosis has risen considerably since the 1970s as the area planted with this species has increased. In order to reduce the amount of pollen dispersed, breeding programs using trees with male-sterile genes have been implemented. We have constructed partial linkage maps surrounding a male sterility gene (ms-1) in four families of C. japonica to facilitate this process. The marker most closely linked to ms-1 was different in the four mapping families: gSNP00438, gSNP01452, estSNP00083, and estSNP01228 in the TO13S family (3.1 cM from ms-1); gSNP05835 and gSNP06239 in the S3T67 family (2.0 cM from ms-1); gSNP05835 in the F1N4 family (1.5 cM from ms-1); and gSNP06239 in the T5 family (4.2 cM from ms-1). This is probably mainly due to genetic differences between the parents used to produce the mapping families. However, in all four families, the accuracy with which male-sterile trees could be identified using the closest markers was more than 96.0 %. These results suggested that marker-assisted selection of male-sterile trees within a given family is feasible using the closest flanking markers to the ms-1 locus. We also developed an allele-specific PCR marker for identifying male-sterile trees in the TO13S family from which male-sterile seedlings are produced. Allele-specific PCR using three primer combinations produced two clear fragments, which could be easily separated by agarose gel electrophoresis: one fragment with a molecular weight of 410 bp, which was present in all samples and could thus be used as a positive control, and another of lower molecular weight (196 bp), which was specific for male-sterile trees. This marker makes it possible to carry out a simple and economical PCR assay for the detection of the SNP linked to the target gene without the need to use fluorescent labels. This study shows how a simple allele-specific PCR marker for an important major gene in a forest tree species can be developed using information from a high-density linkage map. In addition, our results will facilitate the first application of MAS (marker assisted selection) in conifers because the male sterility in C. japonica has several advantages and may be one of the best examples for MAS in conifers.  相似文献   
5.
Cryptomeria japonica pollinosis is one of the most serious allergic diseases in Japan; this is a social problem because C. japonica is the most important Japanese forestry species. In order to reduce the amount of pollen dispersed, breeding programs using trees with male-sterile genes have been implemented. High-density linkage maps with stable ordering of markers facilitate the localization of male-sterile genes and the construction of partial linkage maps around them in order to develop markers for use in marker-assisted selection. In this study, a high-density linkage map for C. japonica with 2560 markers was constructed. The observed map length was 1266.2 cM and the mean distance between adjacent markers was 0.49 cM. Using information from this high-density map, we newly located two male-sterile genes (ms3 and ms4) on the first and fourth linkage groups, respectively, and constructed partial linkage maps around these loci. We also constructed new partial linkage maps around the ms1 and ms2 loci using additional SNP markers. The closest markers to the ms1, ms2, ms3, and ms4 male-sterile loci were estSNP04188 (1.8 cM), estSNP00695 (7.0 cM), gSNP05415 (3.1 cM), and estSNP01408 (7.0 cM) respectively. These results allowed us to develop SNP markers tightly linked to the male sterile genes for use in MAS; this will accelerate the future isolation of these genes by map-based cloning approaches.  相似文献   
6.
7.
To clarify the insulin-releasing mechanism, we studied insulin release and the efflux of [32P]phosphate by glucose at 0.1 mM/min of gradient level or at 16.7 mM, and other metabolism in islets of rat Langerhans. When treated with 1 mM iodoacetic acid (IAA) plus the anomers of D-glucose at 2.8 mM for 6 min at 37 degrees C, islets elicited insulin at half the control rate under the step-wise stimulation by glucose and at the same rate as the control under the slow-rise stimulation by glucose. Using islets treated with IAA plus the alpha anomer at 16.7 mM, the step-wise stimulation secreted insulin at half a rate of the control and the slow-rise stimulation at the rate lower than the control, which was not significantly different from the control rate. Treatment with IAA plus the beta anomer at 16.7 mM inhibited insulin release under both types of stimulations by glucose. The step-wise stimulation caused the same rapid efflux of [32P]phosphate from IAA-treated islets as from the control islets, except for islets treated with IAA plus the beta anomer at 16.7 mM. The rate of glucose utilization in islets was inhibited by all IAA-treatments to the same extent, being merely half the control rate. Treatments with IAA plus the anomers at 16.7 mM significantly reduced the formation of [3H]-cAMP and the activity of protein phosphokinase in islets, while in the presence of the anomers at 2.8 mM IAA produced no significant effect. Neither IAA-treatments altered the uptake of 45Ca and the ATP content in islets. The uptake of [14C]IAA was significantly enhanced by the presence of the beta anomer at 16.7 mM to two times the control level. On the basis of these results, we suggested that the B cell might contain both glucoreceptors and rate-sensors of glucose controlling insulin release and the former might be less sensitive to IAA as compared with the latter.  相似文献   
8.
    
A strain of Bacillus species which produced an enzyme named glutaryl 7-ACA acylase which converts 7 beta-(4-carboxybutanamido)cephalosporanic acid (glutaryl 7-ACA) to 7-amino cephalosporanic acid (7-ACA) was isolated from soil. The gene for the glutaryl 7-ACA acylase was cloned with pHSG298 in Escherichia coli JM109, and the nucleotide sequence was determined by the M13 dideoxy chain termination method. The DNA sequence revealed only one large open reading frame composed of 1,902 bp corresponding to 634 amino acid residues. The deduced amino acid sequence contained a potential signal sequence in its amino-terminal region. Expression of the gene for glutaryl 7-ACA acylase was performed in both E. coli and Bacillus subtilis. The enzyme preparations purified from either recombinant strain of E. coli or B. subtilis were shown to be identical with each other as regards the profile of sodium dodecyl sulfate-polyacrylamide gel electrophoresis and were composed of a single peptide with the molecular size of 70 kDa. Determination of the amino-terminal sequence of the two enzyme preparations revealed that both amino-terminal sequences (the first nine amino acids) were identical and completely coincided with residues 28 to 36 of the open reading frame. Extracellular excretion of the enzyme was observed in a recombinant strain of B. subtilis.  相似文献   
9.
    
Shorea leprosula is an important timber tree in Southeast Asia. From a genomic library enriched for dinucleotide (CT) repeats, 20 polymorphic microsatellite markers were developed for this species. Polymorphism of these loci was evaluated in a sample of 24 adult individuals from a natural population. The number of alleles ranged from five to 15, and the observed heterozygosity ranged from 0.333 to 0.875. Probability of paternity exclusion, in the case where the mother is known, ranged from 0.285 to 0.784. These markers were also characterized for applicability in S. parvifolia; 16 loci were successfully cross‐amplified and showed high levels of polymorphism.  相似文献   
10.
Surgical vaginal reconstruction was performed by a free skin graft in two patients without a vagina. The postoperative changes in vaginal smears collected from the artificial vaginas were observed for about two years. Marked operation-induced inflammatory changes were observed until the second postoperative month. After the third postoperative month, the background became relatively clear. Cyanophilic and eosinophilic superficial cells, intermediate cells and D?derlein bacilli were observed occasionally in addition to keratotic cells. Six to 12 months after surgery, the vaginal smears showed little abnormality, except for the presence of keratotic cells. The changes in the vaginal smears after the third month show that the artificial vaginal epithelium changed cytologically to an almost normal vaginal mucosa that, although not histologically complete, responded to hormones. The presence of D?derlein bacilli suggests that the regional environment of the artificial vagina was almost the same as that of the normal vagina.  相似文献   
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