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101.
Bieby Voijant Tangahu Siti Rozaimah Sheikh Abdullah Hassan Basri Mushrifah Idris Nurina Anuar Muhammad Mukhlisin 《International journal of phytoremediation》2013,15(7):663-676
Phytoremediation is a technology to clean the environment from heavy metals contamination. The objectives of this study are to threat Pb contaminated wastewater by using phytoremediation technology and to determine if the plant can be mention as hyperaccumulator. Fifty plants of Scirpus grossus were grown in sand medium and 600 L spiked water in various Pb concentration (10, 30 and 50 mg/L) was exposed. The experiment was conducted with single exposure method, sampling time on day-1, day-14, day-28, day-42, day-70, and day-98. The analysis of Pb concentration in water, sand medium and inside the plant tissue was conducted by ICP-OES. Water samples were filtered and Pb concentration were directly analyzed, Pb in sand samples were extracted by EDTA method before analyzed, and Pb in plant tissues were extracted by wet digestion method and analyzed. The results showed that on day-28, Pb concentration in water decreased 100%, 99.9%, 99.7%, and the highest Pb uptake by plant were 1343, 4909, 3236 mg/kg for the treatment of 10, 30, and 50 mg/L respectively. The highest BC and TF were 485,261 on day-42 and 2.5295 on day-70 of treatment 30 mg/L, it can be mentioned that Scirpus grossus is a hyperaccumulator. 相似文献
102.
Mohammed M. Idris Michael C. Thorndyke Euan R. Brown 《Invertebrate neuroscience : IN》2013,13(2):151-165
Although mutations in the huntingtin gene (HTT) due to poly-Q expansion cause neuropathology in humans (Huntington’s disease; HD), the normal function(s) of the gene and its protein (HTT) remain obscure. With new information from recently sequenced invertebrate genomes, the study of new animal models opens the possibility of a better understanding of HTT function and its evolution. To these ends, we studied huntingtin expression pattern and dynamics in the invertebrate chordate Ciona intestinalis. Ciona huntingtin (Ci-HTT) shows a biphasic expression pattern during larval development and prior to metamorphosis. A single form of huntingtin protein is present until the early larval stages, at which time two different mass proteins become evident in the metamorphically competent larva. An antibody against Ci-HTT labeled 50 cells in the trunk mesenchyme regions in pre-hatching and hatched larvae and probably represents the distribution of the light form of the protein. Dual labeling with anti-Ci-HTT and anti-aldoketoreductase confirmed the presence of Ci-HTT in mesenchyme cells. Suppression of Ci-HTT RNA by a morpholino oligonucleotide reduced the number and apparent mobility of Ci-HTT positive cells. In Ciona, HTT expression has a dynamic temporal and spatial expression pattern that in ontogeny precedes metamorphosis. Although our results may reflect a derived function for the protein in pre- and post-metamorphic events in Ciona, we also note that as in vertebrates, there is evidence for multiple differential temporal expression, indicating that this protein probably has multiple roles in ontogeny and cell migration. 相似文献
103.
Priya Gupta Asif Idris Shrikant Mantri Mehar Hasan Asif Hemant Kumar Yadav Joy Kumar Roy Rakesh Tuli Chandra Sekhar Mohanty Samir Vishwanath Sawant 《Molecular breeding : new strategies in plant improvement》2012,30(3):1325-1335
Various programs for genetic improvement in oil yield of the biofuel plant Jatropha curcas L. are currently in progress worldwide. In order to develop strategies for genetic improvement, it is important to estimate the degree of diversity at the genetic level among various genotypes of J. curcas. High-throughput sequencing of complexity-reduced nuclear genomic DNA of J. curcas coupled with computational analysis discovered 2,482 informative single nucleotide polymorphisms (SNPs). Genotyping of selective SNPs among 148 global collections of J. curcas lines and further diversity analysis through NTSYS-pc, DARwin and Structure?2.0 software revealed that a narrow level of genetic diversity existed among the indigenous genotypes as compared to the exotic genotypes of J. curcas. The level of marker informativeness along with distance-based and Bayesian clustering revealed grouping of the accession from Togo (Africa) with various Indian accessions at K?=?4 and K?=?5 values (where K represents the number of populations). The diverse accessions identified in the study will be of further use in genetic improvement of J. curcas through quantitative trait loci and association mapping. 相似文献
104.
Association of Copper and Zinc Levels in Oil Palm (Elaeis guineensis) to the Spatial Distribution of Ganoderma Species in the Plantations on Peat 下载免费PDF全文
Mohd Rashid Mohd Rakib Choon‐Fah Joseph Bong Ahmad Khairulmazmi Abu Seman Idris Mohamadu Boyie Jalloh Osumanu Haruna Ahmed 《Journal of Phytopathology》2017,165(4):276-282
Nutrients are essential for normal physiological processes in plants, and they play important roles in defence mechanisms against pathogens. Oil palms cultivated on peat are more prone to nutrient deficiency, especially micronutrients, and this may affect their susceptibility to Ganoderma species, the major threat to the sustainability of oil palm throughout South‐East Asia. This study was conducted to investigate the association of copper (Cu) and zinc (Zn) in mature oil palm to the spatial distribution of Ganoderma species in the plantations on peat. Foliar samples (frond 17) of oil palm from two plantations (Betong and Miri) on peat in Sarawak, Malaysia, were collected based on the spatial distribution pattern of Ganoderma, and total Cu and Zn were quantified spectrometrically. The experiment was conducted twice at a 1‐year interval. The concentrations of Cu and Zn were significantly lower in oil palms from infected areas in contrast to those from uninfected areas. In addition, oil palms in infected areas in Miri suffered Cu and Zn deficiencies. Furthermore, Cu and Zn were significantly lower in the oil palms in Miri that had higher Ganoderma occurrence, as compared to those in Betong, which had significantly higher Cu and Zn but lower Ganoderma occurrence. 相似文献
105.
Shombe N. Hassan Graciela M. Rusch Håkan Hytteborn Christina Skarpe Idris Kikula 《African Journal of Ecology》2008,46(2):174-185
In Serengeti fire is used as a management tool to improve the forage quality for large herbivores. However, little is known of the effects of fire on grazing resources particularly sward structure, its influence on herbivore forage patch selection and utilization to the relative amount of phytomass consumed in burnt and nonburnt patches. From September 2003 to July 2004, consumption of phytomass by large herbivores was assessed with eight samplings in six grassland sites in the Western Corridor in Serengeti National Park. Each site had burnt and nonburnt plots. Movable cages were used to exclude grazing between samplings and plant material harvests were used to assess phytomass and sward structure changes in time. Nonburnt grasslands had consistently larger phytomass at all sampling events whereas the ratio for live leaf/total phytomass was higher in burnt grassland at early postfire stages, but declined later in the season. Moreover, periodic consumption of both total phytomass and different phytomass components shifted between burnt and nonburnt grasslands, but there were also large site-specific responses. The shift appears to be related to the balance between the amount of phytomass available and the quality of the forage in terms of the ratio between live and total phytomass. The study highlights the significance of maintaining mosaics of burnt and nonburnt areas with an adequate provision of forage amount and quality all year round. 相似文献
106.
Resistance to Striga hermonthica in a maize inbred line derived from Zea diploperennis 总被引:1,自引:0,他引:1
Breeding for resistance to Striga in maize (Zea mays), with paucity of donor source and known mechanisms of resistance, has been challenging. Here, post-attachment development of S. hermonthica was monitored on two maize inbreds selected for field resistance and susceptibility reactions to Striga at the International Institute of Tropical Agriculture. Haustorial invasion of the parasite into roots of these inbreds was examined histologically. Morphological differences were observed between roots of the susceptible and the resistant inbreds. The resistant maize had fewer Striga attachments, delayed parasitic development and higher mortality of attached parasites compared with the susceptible inbred. Striga on the susceptible inbred usually penetrated the xylem and showed substantial internal haustorial development. Haustorial ingress on the resistant inbred was often stopped at the endodermis. Parasites able to reach resistant host xylem vessels showed diminished haustorial development relative to those invading susceptible roots. These results suggest that the resistant inbred expresses a developmental barrier and incompatible response against Striga parasitism. 相似文献
107.
108.
Alnajjar A Idris AM Multzenberg M McCord B 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,856(1-2):62-67
A new capillary electrophoresis (CE) method was developed and validated for the screening of human urine for nineteen drugs of abuse. In order to achieve sufficient separation, the electrolyte composition was modified using beta-cyclodextrin (beta-CD) and organic solvents. To process each sample, a sequential injection-solid-phase extraction (SI-SPE) system was constructed. Using this device, matrix clean-up, extraction, and preconcentration of analytes were performed onto a C(18) cartridge. Optimal separation and detection were obtained using a background electrolyte consisting of 100mM phosphate adjusted to pH 6.0, with 20 mM beta-CD, 5% acetonitrile and 20% isopropanol. Electrokinetic injection was performed at 5 kV for 10s, separation voltage was 25 kV and column temperature was set to 25 degrees C. The separation was carried out in a 67.0 cm x 50 microm fused-silica capillary with UV detection at 214 nm. The combination of SI-SPE and sample stacking showed significant sensitivity enhancement with limits of detection in the range of 5-30 ng ml(-1). A validation study showed good reproducibility of both migration time (RSD=0.003-0.088%) and peak area (RSD=0.54-4.8%). Overall, this automated and miniaturized SI-SPE system provides a rapid, sensitive, and robust procedure for analysis; as well as minimizes sample and solvent consumption. 相似文献
109.
Aging is characterized by the development of an endothelial dysfunction, which affects both the nitric oxide (NO)- and the endothelium-derived hyperpolarizing factor (EDHF)-mediated relaxations, associated with vascular oxidative stress and the activation of the angiotensin system. This study investigated whether red wine polyphenols (RWPs), antioxidants and potent stimulators of NO- and EDHF-mediated relaxations improve aging-related endothelial dysfunction, and, if so, examined the underlying mechanism. Mesenteric artery reactivity was determined in organ chambers, vascular oxidative stress by dihydroethidine and MitoSOX staining, and expression of target proteins by immunohistochemical staining. Control young rats (16 weeks) received solvent (ethanol, 3% v/v), and middle-aged rats (46 weeks) either solvent or RWPs (100 mg/kg/day) in the drinking water. The acetylcholine-induced endothelium-dependent NO component was slightly reduced whereas the EDHF component was markedly blunted in rings of middle-aged rats compared to young rats. The endothelial dysfunction was associated with oxidative stress, an upregulation of angiotensin II and AT1 receptors and a down-regulation of SK(Ca), IK(Ca), and angiotensin converting enzyme. Intake of RWPs for either one or two weeks improved the NO and the EDHF components of the relaxation, and normalized oxidative stress, the expression of SK(Ca), IK(Ca) and the components of the angiotensin system. The protective effect of the 2-week RWPs treatment persisted for one and two weeks following stopping intake of RWPs. Thus, intake of RWPs caused a persistent improvement of the endothelial function, particularly the EDHF component, in middle-aged rats and this effect seems to involve the normalization of the expression of SK(Ca), IK(Ca) and the angiotensin system. 相似文献
110.
Sera of Sudanese patients with active infections of Schistosoma mansoni or S. haematobium were tested in immunoblots for their reactivity with Mr31/32,000 proteins of adult S. mansoni (Sm31/32). All sera from patients with intestinal (n = 123) and all but one from those with urinary schistosomiasis (n = 35) had antibodies against Sm31/32. These and additional data suggest that both specificity and sensitivity of Sm31/32 to detect schistosome infections are close to 100%. Antibodies against these proteins developed also in monkeys after experimental infection with S. haematobium. Sm31/32 antigens reacted in immunoblots as a doublet with most S. haematobium-patient sera and as a broad band with many S. mansoni-sera suggesting that at least two components are present in the molecular weight region of Mr31/32,000. The data demonstrate the potential use of Sm31/32 from adult worms to diagnose patients with intestinal or urinary schistosomiasis in endemic areas. 相似文献