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81.
Nonspecific lipid transfer proteins (nsLTPs) facilitate the transfer of phospholipids, glycolipids, fatty acids and steroids between membranes, with wide-ranging binding affinities. Three crystal structures of rice nsLTP1 from Oryza sativa, complexed with myristic (MYR), palmitic (PAL) or stearic acid (STE) were determined. The overall structures of the rice nsLTP1 complexes belong to the four-helix bundle folding with a long C-terminal loop. The nsLTP1-MYR and the nsLTP1-STE complexes bind a single fatty acid while the nsLTP1-PAL complex binds two molecules of fatty acids. The C-terminal loop region is elastic in order to accommodate a diverse range of lipid molecules. The lipid molecules interact with the nsLTP1-binding cavity mainly with hydrophobic interactions. Significant conformational changes were observed in the binding cavity and the C-terminal loop of the rice nsLTP1 upon lipid binding.  相似文献   
82.
Li  Mengyuan  Yang  Jiali  Ye  Chuantao  Bian  Peiyu  Yang  Xiaofei  Zhang  Haijun  Luo  Chuanyu  Xue  Zhifeng  Lei  Yingfeng  Lian  Jianqi 《中国病毒学》2021,36(6):1554-1565
Virologica Sinica - Japanese encephalitis virus (JEV) is a leading cause of viral encephalitis in endemic regions of Asia. The neurotropism of JEV and its high-efficiency replication in neurons are...  相似文献   
83.
Laboratory colonies of cotton bollworm larvae, Helicoverpa armigera, were kept at 20 °C under a photoperiod of L:D = 10:14 and fed on three host plants (cotton, tobacco, kidney bean) and an artificial diet (control) to determine the dynamic effects of larval host quality on over-wintering physiology and mortality. Energy reserves (glycogen and lipid), super-cooling points (SCPs), low-molecular-weight sugars, temperature, and mortality were monitored from November 2002 to April 2003. Lipid content did not change much for each group during over-wintering, but differed according to larval host plants. Larval host plants obviously influence the amount of glycogen, as does time of year: glycogen was lowest in February and increased in early spring. During winter, the mean pupal SCPs increased the most in February, then decreased, and were also affected by larval host plant, i.e. over-wintering pupae reared on kidney bean had the highest SCPs. Levels of glycerol and inositol differed significantly among host plants and months, which peaked in February. Pupal mortality also varied according to larval host plants and time: pupae reached their highest mortality in March and showed host plant differences in January. Records show that February was the coldest month during the period we observed, which corresponded closely to changes in over-wintering characteristics.  相似文献   
84.
It is very important to obtain the parameters of deformation size and contraction frequency of women's uterine musculature in medical research. This paper proposes a type of sensor for measuring these parameters and analyzes its force situation. The flexibility of the sensor makes it easy for doctors to let the sensor pass through woman's narrow cervix and get to her uterine cavity. The experiment shows that the sensitivity of three coils in the sample sensor achieves 22.38 nH/mm2 both for left and right coils, 22.84 nH/mm2 for top coil, which can meet the requirements of sensitivity for testing the contraction situation of uterine musculature. Furthermore, an interface designed in the back end system can display the parameters of deformation size and vivid contraction situation of women's uterine musculature in real-time. The sensor has been applied in some medical fields.  相似文献   
85.
86.
GdX, also named ubiquitin‐like protein 4A, is a ubiquitin‐domain protein characterized by a ubiquitin‐like domain that regulates the movement of misfolded proteins from the endoplasmic reticulum membrane to proteasome. However, its function in skeletal biology remains unclear. Here, we report that GdX plays a crucial role in skeletal development as mice lacking GdX exhibit skeletal dysplasias, mild kyphosis, and scoliosis. During embryonic stage, GdX knockout mice display decreased bone mineral density and trabecular bone accompanied by delayed osteogenic formation. GdX knockout mice also have blended spine and small body size. At the molecular level, GdX knockout mice showed perturbed expression of osteogenesis‐related genes and cartilage developmental genes, indicative of altered differentiation of mesenchymal cell lineage. Collectively, our results uncovered GdX as a novel regulator in bone development and a potential candidate gene for skeletal dysplasias.  相似文献   
87.
Sequencing batch reactors were used to study anaerobic ammonium oxidation (anammox) process under temperature shock. Both long-term (15–35 °C) and short-term (10–50 °C) temperature effects on nitrogen removal performance were performed. In reactor operation test, the results indicated that ammonium removal rate decreased from 0.35 kg/(m3 day) gradually to 0.059 kg/(m3 day) when temperature dropped from 35 to 15 °C. Although bacteria morphology was not modified, sludge settling velocity decreased with decreasing temperature. In batch test, apparent activation energy (Ea) increased with decreasing temperature, which suggested the activity decrease of anaerobic ammonium oxidizing bacteria (AAOB). Low temperature inhibited AAOB and weakened nitrogen removal performance. The cardinal temperature model with inflection was first used to describe temperature effect on anammox process. Simulated results revealed that anammox reaction could occur at 10.52–50.15 °C with maximum specific anammox activity of 0.50 kg/(kg day) at 36.72 °C. The cold acclimatization of AAOB could be achieved and glycine betaine could slightly improve nitrogen removal performance at low temperature.  相似文献   
88.
A sequencing batch reactor was employed to treat the acrylic fiber wastewater. The dissolved oxygen and mixed liquor suspended solids were 2–3 and 3,500–4,000 mg/L, respectively. The results showed ammonium oxidizing bacteria (AOB) had superior growth rate at high temperature than nitrite oxidizing bacteria (NOB). Partial nitrification could be obtained with the temperature of 28 °C. When the pH value was 8.5, the nitrite-N accumulation efficiency was 82 %. The combined inhibitions of high pH and free ammonium to NOB devoted to the nitrite-N buildup. Hydraulic retention time (HRT) was a key factor in partial nitrification control, and the optimal HRT was 20 h for nitrite-N buildup in acrylic fiber wastewater treatment. The ammonium oxidation was almost complete and the transformation from nitrite to nitrate could be avoided. AOB and NOB accounted for 2.9 and 4.7 %, respectively, corresponding to the pH of 7.0. When the pH was 8.5, they were 6.7 and 0.9 %, respectively. AOB dominated nitrifying bacteria, and NOB was actually washed out from the system.  相似文献   
89.
Molecular and Cellular Biochemistry - Secretory phospholipase A2 IIa (sPLA2 IIa) catalyzes the production of multiple inflammatory mediators that influence the development of lung and other...  相似文献   
90.
A compact plasmonic lens is proposed in this paper. This plasmonic lens consists of rectangular holes etched on the silver film and arranged on one straight line and possesses the characteristics of short focus length, ultrathin thickness, and strong focus ability. The theoretical design for the plasmonic lens abides by the constructive interference theorem, and the surface plasmon polaritons excited by the holes with linearly polarized light illumination focuses effectively. The plasmonic lenses with single and double focus spots are provided, and the simulation experiment gives the powerful verification. The distinct structure feature and the excellent focusing characteristic of this plasmonic lens are benefit for its applications in optical integration.  相似文献   
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