首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   327篇
  免费   11篇
  338篇
  2023年   2篇
  2022年   14篇
  2021年   17篇
  2020年   6篇
  2019年   8篇
  2018年   8篇
  2017年   14篇
  2016年   18篇
  2015年   12篇
  2014年   21篇
  2013年   38篇
  2012年   29篇
  2011年   28篇
  2010年   19篇
  2009年   20篇
  2008年   10篇
  2007年   14篇
  2006年   9篇
  2005年   7篇
  2004年   5篇
  2003年   3篇
  2002年   8篇
  2001年   7篇
  2000年   3篇
  1999年   1篇
  1998年   2篇
  1997年   2篇
  1994年   2篇
  1993年   1篇
  1992年   2篇
  1991年   3篇
  1990年   2篇
  1989年   2篇
  1983年   1篇
排序方式: 共有338条查询结果,搜索用时 15 毫秒
1.
Transient receptor potential ion channel melastatin subtype 8 (TRPM8) is activated by cold temperature and cooling agents, such as menthol and icilin. Compounds containing peppermint are reported to reduce symptoms of environmental cold stress such as cold allodynia in dorsal root ganglion (DRG) neuron; however, the underlying mechanisms of action are unclear. We tested the effects of physiological heat (37°C), anthralic acid (ACA and 0.025 mM), 2-aminoethyl diphenylborinate (2-APB and 0.05) on noxious cold (10°C) and menthol (0.1 mM)-induced TRPM8 cation channel currents in the DRG neurons of rats. DRG neurons were freshly isolated from rats. In whole-cell patch clamp experiments, TRPM8 currents were consistently induced by noxious cold or menthol. TRPM8 channels current densities of the neurons were higher in cold and menthol groups than in control. When the physiological heat is introduced by chamber TRPM8 channel currents were inhibited by the heat. Noxious cold-induced Ca2+ gates were blocked by the ACA although menthol-induced TRPM8 currents were not blocked by ACA and 2-APB. In conclusion, the results suggested that activation of TRPM8 either by menthol or nociceptive cold can activate TRPM8 channels although we observed the protective role of heat, ACA and 2-APB through a TRPM8 channel in nociceptive cold-activated DRG neurons. Since cold allodynia is a common feature of neuropathic pain and diseases of sensory neuron, our findings are relevant to the etiology of neuropathology in DRG neurons.  相似文献   
2.

Cotton fibre quality is a multigenic trait. Genetic modification of different genes to achieve high quality fibre is difficult without knowing the mechanism lying behind genes interaction. Based on background knowledge an attempt to explore the potential structural interactions between Gossypium hirsutum Wlim5 domain1 and Gossypium hirsutum ACTIN-1 proteins was done in current study. Sequence features of the LIM domain1 of GhWlim5 protein were identified through multiple sequence alignment analysis, and a phylogenetic tree was built to identify evolutionary relationships between sequences. Conservation indicated the evolutionary importance of side chain residues and the presence of several aliphatic and/or bulky residues, which stabilize the protein core and facilitate packing of zinc fingers. The structures of GhWlim5 domain1 and GhACTIN-1 proteins were modelled and validated through computational methods. Validation of GhACTIN-1 and GhWlim5 domain1 structures indicated good structural quality with 99.7% and 100% of the favoured number of residues in allowed regions and Z-score, within the ranges of − 9.87 and − 4.17, respectively. Docking analysis indicated various possible modes of interaction between these two proteins with favourable binding affinities. Based on our strong binding interaction results between GhWlim5 domain1 and GhACTIN-1 proteins, we further investigated the role of over-expression of GhWlim5 by transformation in cotton plants under fibre specific promoter and transgenic plants displayed significant increases in fibre strength.

  相似文献   
3.
Present study focuses on ameliorative potential of Typha elephantina leave’s aqueous (TE.AQ) extract against Paracetamol (PCM) induced toxicity in rabbits. We fed the male rabbits with 300 mg PCM in alone and in combination with TE.AQ at different doses i.e. (100, 200 and 300 mg/kg body weight) or silymarin (100 mg/kg) daily for 21 days. PCM in alone significantly (P < 0.5) increased serum urea, uric acid, creatinine, total protein, albumin, globulin and blood urea nitrogen. Serum sodium, potassium and magnesium level were high. The glutathione, radical scavenging activity and Thiobarbituric acid reactive substances were significantly reduced. Treatment with TE.AQ at dose rate 300 mg/kg body weight and Silymarin significantly ameliorated all the parameters when compared with PCM administered group. The 100 and 200 mg of TE.AQ showed no significant effects. The histopathological examination confirmed the therapeutic potential of TE.AQ. These results established the presence of natural antioxidants in Typha elephantina leaves.  相似文献   
4.
Root-knot nematodes Meloidogyne incognita (Kofoid and White) Chitwood and Rhizoctonia bataticola (Taub.) Butler, fungus, are very dangerous root damaging pathogens. Present study was planned to establish a chemical control of these root deteriorating pathogens under lab conditions as well as in field. Maximum death rate of nematode juveniles and minimum numbers of nematode eggs hatched were recorded in plates treated with Cadusafos (Rugby® 100G) @12 g/100 ml and Cartap® (4% G) @9g/100 ml. Chemical treatment of Rhizoctonia bataticola with Trifloxystrobin + Tebuconazole (Nativo®) @0.2 g/100 ml and Mancozeb + Matalaxyl (Axiom) @0.25 g/100 ml significantly controlled the mycelial growth in plates. The best treatments tested in laboratory were applied in field as protective and curative treatments. Results proved that chemical control of root-knot nematode and root rot fungi by tested chemicals at recommended time and dose is a significant management technique under field conditions.  相似文献   
5.
In the spectrophotometric assay of multicomponent systems involved in drug degradation studies, some minor or unknown degradation products may be present. These products may interfere in the assay and thus invalidate the results due to their absorption in the range of analytical wavelengths. This interference may be eliminated by the application of an appropriate correction procedure to obtain reliable data for kinetic treatment. The present study is based on the application of linear and non-linear irrelevant absorption corrections in the multicomponent spectrophotometric assay of riboflavin and formylmethylflavin during the photolysis and hydrolysis studies. The correction procedures take into account the interference caused by minor or unknown products and have shown considerable improvement in the assay data in terms of the molar balance. The treatment of the corrected data has led to more accurate kinetic results in degradation studies.  相似文献   
6.
Biological Trace Element Research - For physiological and biochemical studies, it is considered essential to have knowledge about the accumulation of mineral elements in plants and their...  相似文献   
7.
An experiment was conducted to test the effect of different doses of 2, 4 and 8?g/2?kg of soil of Pochonia chlamydosporia against the root-knot nematode (Meloidogyne incognita) on Phaseolus vulgaris. It was observed that inoculation of plant with the nematode alone, and 15?days prior to fungal inoculation, reduced the plant growth when compared with the plant with fungal application followed by the nematode. Plant length, fresh and dry weight, chlorophyll, carotenoid, protein contents and nitrate reductase activity decreased in nematode-infested plants. Application of higher dose of 8?g/2?kg of soil of P. chlamydosporia increased all the plant growth parameters as well as biochemical parameters. Highest number of galls per root system was recorded on the plants infested with nematode but not treated with the fungus. However, application of fungus prior to nematode inoculation improved the plant growth and reduced the number of galls and the number of egg masses per root system.  相似文献   
8.
The liver is considered a radiosensitive organ. However, in rats, high single-dose irradiation (HDI) showed only mild effects. Consequences of fractionated irradiation (FI) in such an animal model have not been studied so far. Rats were exposed to selective liver FI (total dose 60 Gy, 2 Gy/day) or HDI (25 Gy) and were killed three months after the end of irradiation. To study acute effects, HDI-treated rats were additionally killed at several time points between 1 and 48 h. Three months after irradiation, no differences between FI and HDI treatment were found for macroscopically detectable small “scars” on the liver surface and for an increased number of neutrophil granulocytes distributed in the portal fields and through the liver parenchyma. As well, no changes in HE-stained tissues or clear signs of fibrosis were found around the portal vessels. Differences were seen for the number of bile ducts being increased in FI- but not in HDI-treated livers. Serum levels indicative of liver damage were determined for alkaline phosphatase (AP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase (γGT) and lactate dehydrogenase (LDH). A significant increase of AP was detected only after FI while HDI led to the significant increases of AST and LDH serum levels. By performing RT-PCR, we detected up-regulation of matrix metalloproteinases, MMP-2, MMP-9, MMP-14, and of their inhibitors, TIMP-1, TIMP-2 and TIMP-3, shortly after HDI, but not at 3 month after FI or HDI. Overall, we saw punctual differences after FI and HDI, and a diffuse formation of small scars at the liver surface. Lack of “provisional clot”-formation and absence of recruitment of mononuclear phagocytes could be one explanation for scar formation as incomplete repair response to irradiation.  相似文献   
9.
10.
Biodiesel is considered as a potential alternative energy source, but problem exists with the quantity and quality of feedstock used for it. To improve the feedstock quality of biodiesel, a field experiment was conducted under natural conditions. Cultivar Thori of kasumbha was used in the experiment. Commercialized biofertilizers were applied at the rate of 20 kg per acre and chemical fertilizer (diammonium phosphate) was applied as half dose (15 kg/ha). Results indicated that number of leaf plant−1, leaf area, number of seeds capitulum−1 was significantly increased by biofertilizer treatment alone (BF) and combine treatment of biofertilizer and chemical fertilizer (BFCF). Agronomic traits such as plant height, no. of branches of a plant, no. of capitulum/plant was improved significantly by BF treatment over the control. Maximum 1000 seed weight (41%) and seed yield (23%) were recorded in half dose of chemical fertilizers treatment (CFH). Seed oil content and seed phenolics were significantly improved by BF and CF treatments while maximum biodiesel yield was recorded by BF treatment. Maximum oleic acid was recorded by BF treatment while other fatty acids being maximum in control except linoleic acid in BFCF treatment. Results for specific gravity were non-significant while acid value and free fatty acid contents were substantially reduced by BF treatment as compared to other treatments. Maximum value of iodine number was recorded in BFCF treatment while tocopherol contents were improved by BF treatment. It is inferred that biofertilizer treatment alone perform better as compared to other treatments and 50% chemical fertilizer can be replaced using biofertilizer which is a good approach for sustainable environmental-friendly agriculture.Keyword: Green energy, Biofuel, Biodiesel, Kasumbha, Biofertilizers, Fatty acid, NMR  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号