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991.
Flexible Solar Cells: Charge Transport Modulation of a Flexible Quantum Dot Solar Cell Using a Piezoelectric Effect (Adv. Energy Mater. 3/2018) 下载免费PDF全文
992.
993.
Low‐power laser irradiation decreases lipid droplet accumulation in the parotid glands of diabetic rats 下载免费PDF全文
Juliana R. de Castro Eugen M. N. de Souza Yun‐Jong Park Luana de Campos Seunghee Cha Victor E. Arana‐Chavez José Nicolau Alyne Simões 《Journal of biophotonics》2018,11(4)
Lipid droplet accumulation has been related to salivary gland hypofunction in diabetes. In this study, the effect of laser irradiation on the parotid glands (PGs) of diabetic rats was analyzed with regard to its effect on lipid droplet accumulation, intracellular calcium concentration and calmodulin expression. The animals were distributed into 6 groups: D0, D5, D20 and C0, C5, C20, for diabetic (D) and control animals (C), respectively. Twenty‐nine days following diabetes induction, PGs of groups D5 and C5; D20 and C20 were irradiated with 5 and 20 J/cm2 of a red diode laser at 100 mW, respectively. After 24 hours, PGs were removed for histological, biochemical, and western blotting analysis. The diabetic animals showed lipid droplet accumulation, which was decreased after irradiation. Ultrastructurally, the droplets were nonmembrane bound and appeared irregularly located in the cytoplasm. Moreover, diabetic animals showed an increased intracellular calcium concentration. In contrast, after laser irradiation a progressive decrease in the concentration of this ion was observed, which would be in agreement with the results found in the increased expression of calmodulin in D20. These data are promising for using laser to decrease lipid droplet accumulation in PGs, however, more studies are necessary to better understand its mechanisms. Micrographs showing decreased lipid accumulation after laser irradiation in light micrographs (LM), and morphology of lipid droplet in transmission electron microscopic (TEM). LM: (A) PGs from nondiabetic rats that did not receive Laser irradiation (LI), (B) PGs from nondiabetic rats that received a dose of 20 J/cm2, (C) lipid accumulation (arrows) in the secretory cells from diabetic rats that did not receive irradiation, (D) reduction of lipid accumulation in the secretory cells from diabetic rats that received a dose of 20 J/cm2 and TEM: (E) scale bar = 5 μm, (F) scale bar = 1 μm, and (G) scale bar = 0.5 μm. 相似文献
994.
995.
Extensive shrimp farming around Deep Bay, Hong Kong,began in the mid-1940‘s after the construction of intertidal ponds (gei
wai) among the coastal mangroves. The ponds are increasingly being seen as an example of how wetlands can be used sustainablysince
they are naturally stocked with shrimp postlarvae (e.g. Metapenaeus ensis) and young fish (e.g. Mugil cephalus) flushed into
the ponds from Deep Bay. Once inside, these shrimps and fish feed on naturally occurring detritus on the pond floor. The only
gei wai remaining in the Territory, are those at the WWF Hong Kong Mai Po Marshes Nature Reserve, adjacent to Deep Bay. Analysis
of the shrimp production between 1990–1995 showed that there were two seasonal peaks, from April–June (Recruitment-I)and from
July–October (Recruitment-II). The second peak was significantly lower than the first (p <0.001), especially from those gei
wai in the southern part of the reserve which are much closer to a polluted river. The average harvest from each gei wai had
also significantly declined from40.9 ±6.0 kg ha−1 yr−1 in 1990 to15.1 ±3.6 kg ha−1 yr−1 in 1995 (p <0.01). This decline can be attributed to the abundance of predatory fish in the gei wai, and increasing water
pollution in Deep Bay which adversely affects the amount of shrimp larvae for stocking the gei wai, as well as the quality
of water for flushing the ponds during the rearing and harvesting seasons. Despite this, those gei wai which are not-commercially
viable can still support many non-commercial, more pollution tolerant fish and shrimp species. As a result, the management
of the segei wai has been altered such that their objective is to provide feeding habitat for piscivorous waterbirds, which
is also in line with the aims of the nature reserve.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
996.
Summary The conventional saccharification of cassava root by enzymatic hydrolysis is improved by using a little amount of cellulase and cellobiase in addition to conventional enzyme, glucoamylase. With new saccharification[glucoamylase 0.45SGU/g cassava, cellulase 4.5NCU/g cassava, cellobiase 0.09U/g cassava, pH 4.3, temperature 60°C, total volume 465ml : 100g of cassava/400ml of water], the reaction time was reduced by about 5 hours, the concentration of reducing sugar was increased by 40%, glucose production was enhanced by 10% , and the viscosity was reduced by 30%. 相似文献
997.
Drosophila bicoid mRNA is synthesized in the nurse cells and transported to the oocyte where microtubules and Exuperantia protein mediate localization to the anterior pole. Fluorescent bicoid mRNA injected into the oocyte displays nonpolar microtubule-dependent transport to the closest cortical surface, and the oocyte microtubule cytoskeleton lacks clear axial asymmetry. Nonetheless, bicoid mRNA injected into the nurse cell cytoplasm, withdrawn, and injected into a second oocyte shows microtubule-dependent transport to the anterior cortex. Nurse cells require microtubules and Exuperantia to support anterior transport of bicoid mRNA, and microtubules are required for bicoid mRNA-Exuperantia particle coassembly. We propose that microtubule-dependent Exuperantia-bicoid mRNA complex formation in the nurse cell cytoplasm allows anterior-specific transport on a grossly nonpolar oocyte microtubule network. 相似文献
998.
The effects of physical and chemical factors on the production of H2 O2 from Escherichia coli cells were studied. When 20 mmol 1-1 Tris-HCl buffer was used for this purpose the electron transport system (ETS) showed the highest activity at pH 7.6-8.2. KCN promoted the production of H2 O2 from E. coli cells, and the optimum concentration was changed in different reaction times and pH values. Glucose, 5 mg ml-1 , increased the ETS activity about twofold. The other substrates and surfactants did not increase the chemiluminescence intensity. NaNO2 and Na2 SO4 in inorganic salts significantly reduced the ETS activity above 70%. In addition, the optimum temperature for the production of H2 O2 was 30°C in this study. When glucose (5 mg ml-1 ) and KCN (0.2 mmol 1-1 ) were added to the reaction buffer containing 0.5 mmol 1-1 menadione, the detectable minimum cell densities (averages of triplicate assay) of E. coli, Enterobacter cloacae and Serratia marcescens were 5 times 103 cells ml-1 , 104 cells ml-1 and 104 cells ml-1 respectively. 相似文献
999.
1000.
Hae-Sim Cha Wan-Joong Kim Myung-Hun Lee Sun-Young Kim Seo Ho Kim Kwang-Ho Lee 《Bioscience, biotechnology, and biochemistry》2016,80(5):911-919
Pterocarpus indicus Willd has been widely used as a traditional medicine to treat edema, cancer, and hyperlipidemia, but its antiallergic properties and underlying mechanisms have not yet been studied. The purpose of this study was to evaluate the antiallergic activity of Pterocarpus indicus Willd water extract (PIW) using activated mast cells and an atopic dermatitis (AD)-like mouse model. PIW decreased IgE/Ag-induced mast cell degranulation and the phosphorylation of Syk and downstream signaling molecules such as PLC-γ, Akt, Erk 1/2, JNK compared to stimulated mast cells. In DNCB-induced AD-like mice, PIW reduced IgE level in serum, as well as AD-associated scratching behavior and skin severity score. These results indicate that PIW inhibits the allergic response by reducing mast cell activation and may have clinical potential as an antiallergic agent for disorders such as AD. 相似文献