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901.
The objective of present study was to evaluate the variation in phenolic profile, β‐carotene, flavonoid contents, antioxidant and antimicrobial properties of Tagetes erecta and Tagetes patula (T. erecta and T. patula) through different in vitro assays. Antioxidant activity was determined through 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) free radical scavenging and inhibition of linoleic acid peroxidation assays and antibacterial and antifungal activities studied using the disc diffusion and resazurin microtiter‐plate assays against bacterial and fungal strains. Moreover, total phenolics (TP), total carotenoids (TC) and total flavonoids (TF) were also determined. Highest (TP 35.8 mg GAE/g) and TF (16.9 mg CE/g) contents were found in MeOH extract of T. patula. T. erecta extract showed higher TC contents (6.45 mg/g) than T. patula extract (6.32 mg/g). T. erecta exhibited the highest DPPH radical‐scavenging activity (IC50) (5.73 μg/mL) and inhibition of linoleic acid peroxidation (80.1%). RP‐HPLC revealed the presence of caffeic acid, sinapic acid and ferulic acid in Tagetes extracts, m‐coumaric acid in T. erecta whereas chlorogenic acid in T. patula extract only. Both extracts possessed promising antimicrobial activity compared to the ciprofloxacin and flumequine (+ve controls) against Bacillus subtilis and Alternaria alternate. Both extract were rich source of polyphenols exhibiting excellent biological activities.  相似文献   
902.
Kidney bean (Phaseolus vulgaris) plants exhibiting foliar yellow mosaic symptoms and some leaf crumpling were identified in the Al Batinah region of Oman. Rolling circle amplification and polymerase chain reaction identified a bipartite begomovirus (family Geminiviridae) and a betasatellite in association with the symptomatic plants. Analysis of full‐length sequences showed the virus to be Mungbean yellow mosaic Indian virus (MYMIV) and the betasatellite Tomato leaf curl betasatellite (ToLCB). This is the first identification of a legume‐adapted begomovirus in Oman and the first identification of MYMIV in association with the betasatellite ToLCB. The isolate of MYMIV from Oman shows the greatest levels of sequence identity to isolates occurring in South Asia and South‐East Asia, suggesting that the virus has only recently been introduced. The significance of these findings is discussed.  相似文献   
903.
Non-coding RNAs (ncRNAs) are critical regulators of gene expression in essentially all life forms. Long ncRNAs (lncRNAs) and microRNAs (miRNAs) are two important RNA classes possessing regulatory functions. Up to date, many primate-specific ncRNAs have been identified and investigated. Their expression specificity to primate lineage suggests primate-specific roles. It is thus critical to elucidate the biological significance of primate or even human-specific ncRNAs, and to develop potential ncRNA-based therapeutics. Here, we have summarized the studies regarding regulatory roles of some key primate-specific lncRNAs and miRNAs.  相似文献   
904.
Three hundred and eleven honeybee samples from 12 countries in the Middle East and North Africa (MENA) (Jordan, Lebanon, Syria, Iraq, Egypt, Libya, Tunisia, Algeria, Morocco, Yemen, Palestine, and Sudan) were analyzed for the presence of deformed wing virus (DWV). The prevalence of DWV throughout the MENA region was pervasive, but variable. The highest prevalence was found in Lebanon and Syria, with prevalence dropping in Palestine, Jordan, and Egypt before increasing slightly moving westwards to Algeria and Morocco Phylogenetic analysis of a 194 nucleotide section of the DWV Lp gene did not identify any significant phylogenetic resolution among the samples, although the sequences did show consistent regional clustering, including an interesting geographic gradient from Morocco through North Africa to Jordan and Syria. The sequences revealed several clear variability hotspots in the deduced amino acid sequence, which furthermore showed some patterns of regional identity. Furthermore, the sequence variants from the Middle East and North Africa appear more numerous and diverse than those from Europe.  相似文献   
905.
The present study aimed to quantify the methyl esters of lenoleic acid (LA), γ-lenolenic acid (LNA) and oleic acid (OL) in the oil of Brassica napus mutants. Five stable mutants (ROO-75/1, ROO-100/6, ROO-125/12, ROO-125/14, and ROO-125/17)of B. napus cv. 'Rainbow' (P) and three mutants (W97-95116, W97-0.75/11 and W97-.075/13) of B. napus cv. 'Westar' (P) at M6 stage, exhibiting better yield and yield components, were analyzed for essential fatty acids. The highest seed yield was observed in the mutant (ROO-100/6) followed by ROO-125/14 of Rainbow, that is, 34% and 32% higher than their parent plants, respectively. Westar mutant W97-75/11 also showed 30% higher seed yield than its parent plant. High performance liquid chromatography analysis of the composition of fatty acids indicated that OL was the most dominant fatty acid, ranging from 39.1 to 66.3%; LA was second (15.3-41.6%) and LNA was third (18.1-28.9%). Mutant ROO-125/14 showed higher OL contents than parent (Rainbow). These results are expected to support the approval of ROO-125/14 in the National Uniform Varietal Yield Trials (NUVYT) as a new variety based on high oil quality.  相似文献   
906.
This work explores the thermoluminescence (TL) and photoluminescence (PL) properties of Ag/Y co-doped zinc oxide (ZnO) nanophosphor. The proposed dosimeter was prepared by the coprecipitation method and sintered at temperatures from 400°C to 1000°C in an air atmosphere. Raman spectroscopy was studied to investigate the structural features of this composition. The new proposed dosimeter revealed two peaks at 150°C and 175°C with a small shoulder at high temperature (225°C). The PL spectrum showed strong green emissions between 500 to 550 nm. The Raman spectrum showed many bands related to the interaction between ZnO, silver (Ag), and yttrium oxide (Y2O3). The rising sintering temperature enhanced the TL glow curve intensity. The Ag/Y co-doped ZnO nanophosphor showed an excellent linearity index within a dose from 1 to 4 Gy. The minimum detectable dose (MDD) of the Ag/Y co-doped ZnO nanopowder (pellets) equaled 0.518 mGy. The main TL properties were achieved in this work as follows: thermal fading (37% after 45 days at 1 and 4 Gy), optical fading (53% after 1 h and 68% after 6 h by exposure to sunlight), effective atomic number (27.6), and energy response (flat behavior from 0.1 to 1.3 MeV). Finally, the proposed material shows promising results nominated to be used for radiation measurements.  相似文献   
907.
BackgroundThis dosimetric study compared lateral wedge with medial only cardiac shielding (LEMONADE) technique, for left chest wall (LCW) irradiation against three other commonly used techniques.Materials and methodsDosimetric parameters of 22 consecutive LBC patients treated using the P1 (LEMONADE technique) were compared with 3 other virtually reconstructed plans : no cardiac shielding with paired wedges; P2 (paired wedges and medial only Y-direction shielding) and P3 (paired wedges and bilateral Y-direction shielding).ResultsP1 showed better target volume (TV) coverage with the mean 90% isodose coverage of 85.59% ± 5.44 compared to 78.90% ± 8.59 and 74.22% ± 9.50 for P2 and P3, respectively. Compared to no cardiac shielding, for a 4.65% drop in TV coverage the V26Gy of heart dropped from 6.68% to a negligible 0.85% for P1. TV receiving < 30Gy is also significantly lesser for P1 compared to P2 and P3 (5.42% vs 10.64% and 15.8%), whilst there is a small difference of 2.75% between no cardiac shielding and P1.ConclusionWith the improvement in BC survival rate, cardiac toxicity associated with adjuvant irradiation for LBC is a major concern. P1 (LEMONADE) technique has a good compromise between cardiac sparing and target coverage and should suffice for most LCW irradiations. Furthermore, the LEMONADE technique is a simple, reproducible and involves fast planning for cardiac sparing, which is ideal for under-resourced departments with heavy workload.  相似文献   
908.
On a monoaxial erect stem of trees with continuous leafing, the older leaves would be quickly shaded by newer (upper) leaves if the trees did not have any compensating mechanisms to avoid self-shading. We hypothesized that the dynamic adjustment of leaf deployment, by regulating the patterns of leaf growth and by changing leaf orientation as leaves age, is a compensating mechanism. To verify this hypothesis, we analyzed leaf development and crown structure of a Far Eastern tropical pioneer tree species, Macaranga gigantea (Rub. f. et Toll.) M.A., which unfolds huge leaves directly on a monoaxial stem with a short leafing interval. Petioles required more than 90 days for full elongation and the petiole angle (the angle between the petiole axis and the vertical) increased over time. Thus, a series of leaves on a stem progressively increased in petiole length and petiole angle from the youngest to the oldest leaves. This is beneficial because it decreases the degree of self-shading within a crown. A simulation suggested that an average crown for the M. gigantea seedlings, which was constructed using empirically determined morphometric data cannot entirely eliminate self-shading within the crown. But an average crown had a lower degree of self-shading, with less dry mass allocation to the petiole than simulated crowns that were identical to the average crown in all but one respect: they had constant petiole lengths or petiole angles. We conclude that M. gigantea seedlings reduce self-shading by regulating elongation of the petiole and changes in the petiole angle with increasing leaf age.  相似文献   
909.
Hammour fish (grouper fish) are known to be of great nutritional value for human consumption, as their protein has a high biological value and contains all the essential amino acids. Grouper fish are also a good source of minerals, vitamins, and fats that contain essential fatty acids. Thus, the current study aims to know the effect of different proportion of hummer fish on biochemical and histopathological changes of hyperglycemic rats. Twenty-four (24) Sprague Dawley-strain male albino rats, which weighed 150 ± 10 g, were divided into four groups. One group served as the negative control (normal), while the others were rendered diabetic using alloxan. One of the diabetic groups was considered the positive control and fed a standard diet, whereas the remaining two groups were fed with a 20% and 25% hammour fish diet for 28 days. At the end of the experiment, blood samples were taken from all the rats, and their organs were removed and subjected to biochemical analysis. The results indicated that the group fed with the 25% hammour fish diet exhibited significantly lower levels of liver, kidney, and heart damage, along with lower levels of serum glucose, total cholesterol, triglycerides, LDL, GOT, GPT and ALP, as compared to the positive control. The urea and creatinine levels were significantly higher for the rats that were fed the 20% hammour fish diet than for those in the positive control. The histopathological study of the heart showed a slight improvement of the heart tissues with the increase of hammour fish intake compare to the positive control, while kidney of rat from group 4, which were fed 25% hammour fish, showed granularity of epithelial lining glomerular tufts.  相似文献   
910.
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