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1.
Verticillium wilt (VW) can cause substantial yield loss in hop particularly with the outbreaks of the lethal strain of Verticillium albo-atrum. To elucidate genetic control of VW resistance in hop, an F1 mapping population derived from a cross of cultivar Wye Target, with the predicted genetic basis of resistance, and susceptible male breeding line BL2/1 was developed to assess wilting symptoms and to perform QTL mapping. The genetic linkage map, constructed with 203 markers of various types using a pseudo-testcross strategy, formed ten major linkage groups (LG) of the maternal and paternal maps, covering 552.98 and 441.1 cM, respectively. A significant QTL for VW resistance was detected at LOD 7 on a single chromosomal region on LG03 of both parental maps, accounting for 24.2–26.0 % of the phenotypic variance. QTL analysis for alpha-acid content and yield parameters was also performed on this map. QTLs for these traits were also detected and confirmed our previously detected QTLs in a different pedigree and environment. The work provides the basis for exploration of QTL flanking markers for possible use in marker-assisted selection.  相似文献   
2.
Palomena prasina is interesting for the study of vibrational communication within the Pentatomid subfamily Pentatominae, because its host range is limited to woody plants, unlike the better known Nezara viridula, whose vibrational communication is commonly used as a model for the whole family. The vibrational repertoire of P. prasina was described several decades ago and is redescribed in this paper using modern methods for non-contact vibration recording. Additionally, we hypothesized that this species has retained the capacity for signal frequency variation necessary for tuning to resonance properties of various host plants of Pentatominae, but if the signals are emited in the absence of mechanical feedback, they are tuned more specifically to their native acoustic environment — woody plants. By recording live bugs signalling on different substrates and comparing spectral properties of their signals among substrates, we found that there is a match between the signals emitted on a woody branch and those emitted on a non-resonant surface, while spectral properties of signals emitted on herbaceous plants differ. Our findings provide evidence in support of the signal tuning hypothesis and shed further light on the crucial role of substrate in vibrational communication of insects.  相似文献   
3.
The aim of the study was to determine the incidence of monosymptomatic optic neuritis (MON) in residents of Split-Dalmatia County, Croatia. The 127 cases (83 female, aged 26.2+/-9.9 and 44 male aged 26.9+/-11.2) with MON presented between January 1985 and December 2001 were analyzed from hospital data. The annual incidence was 1.6 per 100,000 (95% CI, 0-3). The incidence among females was 2.2 (95% CI, 0-4.6) cases / 100,000 per year and 1.1 (95% CI, 0-3) among males. The difference in incidence rates for women vs. men was not significant (chi2=0.41; p=0.52), although it is more likely that a true difference exists. The peak incidence in both sexes observed in the group 20-29 years of age was 4.2 (95% CI, 0-10). The highest incidence of MON was found in spring (46 cases). In summary, the incidence of MON in Split-Dalmatia County during the 17 years period is relatively low.  相似文献   
4.
The aim of this paper was to show the potential of Salmonella enteritidis infection to eventually result in visual impairment. A case of salmonellosis in a 6-year-old boy, caused by intake of a cake made from eggs infected with Salmonella enteritidis, is presented. Prolonged duration of the disease was followed by complete remission of neurologic complications and persistent amaurosis with bilateral optic nerve atrophy. A severe form of Salmonella enterocolitis with neurologic involvement can lead to optic nerve lesion with consequential loss of vision.  相似文献   
5.
A comprehensive metabolomic profiling of Catharanthus roseus L. G. Don infected by 10 types of phytoplasmas was carried out using one-dimensional and two-dimensional NMR spectroscopy followed by principal component analysis (PCA), an unsupervised clustering method requiring no knowledge of the data set and used to reduce the dimensionality of multivariate data while preserving most of the variance within it. With a combination of these techniques, we were able to identify those metabolites that were present in different levels in phytoplasma-infected C. roseus leaves than in healthy ones. The infection by phytoplasma in C. roseus leaves causes an increase of metabolites related to the biosynthetic pathways of phenylpropanoids or terpenoid indole alkaloids: chlorogenic acid, loganic acid, secologanin, and vindoline. Furthermore, higher abundance of Glc, Glu, polyphenols, succinic acid, and Suc were detected in the phytoplasma-infected leaves. The PCA of the (1)H-NMR signals of healthy and phytoplasma-infected C. roseus leaves shows that these metabolites are major discriminating factors to characterize the phytoplasma-infected C. roseus leaves from healthy ones. Based on the NMR and PCA analysis, it might be suggested that the biosynthetic pathway of terpenoid indole alkaloids, together with that of phenylpropanoids, is stimulated by the infection of phytoplasma.  相似文献   
6.
CDC traps were used to determine the maximum radius of carbon dioxide attraction within forest habitat (a forest plant community with Carpino betuli-Quercetum roburis). A central CDC trap with dry ice (CO2) was set as the source of attractant (Ck). Around Ck trap two circles (A and B) of CDC traps without attractants were placed. Circle A was constituted of 6 CDC traps and Circles B with 12 CDC traps. Radius from Circle A and B to the Ck trap were used to determine CO2 maximum range. During the experiment, the average emissions of CO2 were 0.08 to 0.1 g s?1. Regarding the data, optimal radius attraction where CO2 was affected on mosquitoes was between 55 and 70 m from the source. Results propose that the distance between traps should be greater than 140 m, to ensure the absence of bias by each of the traps. Changes in CO2 maximum concentration and wind velocity directly affected the catch of different species. The number of Ochlerotatus sticticus collected was positively correlated with wind speed.  相似文献   
7.
BioMetals - This study aimed to investigate the short-term effects of three magnesium (Mg) dietary supplements containing mineral immediately available for absorption on Mg biochemical status...  相似文献   
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9.
Data mining of gene sequences available from various projects dealing with the development of expressed sequence tags (ESTs) can contribute to the discovery of new microsatellite markers. Our aim was to develop new microsatellite markers in hop isolated from an enriched cDNA library and from coding GenBank sequences and to test their suitability in hop diversity studies and for construction of a linkage map. In a set of 614 coding GenBank sequences, 72 containing microsatellites were found (11.7%); the most frequent were trinucleotide repeats (54.0%) followed by dinucleotide repeats (34.5%). Additionally, 11 sequences containing microsatellites were isolated from an enriched cDNA library. A total of 34 primer pairs were designed, 29 based on GenBank sequences and five on sequences from the cDNA enriched library. Twenty-seven (79.4%) coding microsatellites were successfully amplified and used in diversity and linkage mapping studies. Eleven primer pairs amplified 12 coding microsatellite loci suitable for mapping and were placed on female and male linkage maps. We were able to extend previous simple sequence repeat (SSR) female, male and integral maps by 38.8, 25.8 and 40.0 cM, respectively. In the diversity study, 36 diverse hop genotypes were analyzed. Twenty-four coding microsatellites were polymorphic, 17 showing co-dominant behavior and 7 primer pairs amplifying three or more bands in some hop genotypes. Altogether, 143 microsatellite DNA fragments were amplified and they revealed a clear separation of hop genotypes according to geographical region, use or breeding history. In addition, a discussion and comparison of results with other plant coding/EST SSR studies is presented. Our results showed that these microsatellite markers can enhance hop diversity and linkage mapping studies and are a comparable marker system to non-coding SSRs.  相似文献   
10.
Neurofibromatosis type 1 (NF 1) is an autosomal dominant disorder with high index of spontaneous mutations and extremely varied and impredictible clinical manifestations. The aim of this work was to give an account of eye disorders in NF1. 132 patients of age 0-16 years with NF1 were followed up for 15 years. They were checked repeatedly for ophthalmologic disorders. Frequent eye disorders were: Lisch nodules (Iris hamartomas, IH) 78%, hyperthelorism 19.7%, bulbomotoric disorders 15.9%, disorders of the optic disc 16.7% and optic gliomas (18.9%). The highest incidence of eye disorders by NF1 patients showed Lisch nodules (IH). Its ease of clinical recognition and if present with other diagnostic signs (for instance café au lait patches) could be deemed as reliable diagnostic criterion of NF1 in childhood.  相似文献   
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