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991.
Ellabban MA 《Plastic and reconstructive surgery》2008,121(3):1068; author reply 1068
992.
Oxidative stress is thought to play a crucial role in the pathogenesis of chronic diabetic complications. We investigated the protective effects of 17 beta-estradiol (E2) on alloxan-induced stress oxidant, hepatic dysfunction and histological changes in male rats liver and pancreas. Our results showed that 17 beta-estradiol could attenuate the increase of blood glucose in plasma and normalise the hepatic glycogen level. In addition, E2 enhanced superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) (by 207, 52 and 72%, respectively, as compared to diabetic rats), reduced lipid peroxidation in the hepatic tissue (by 54%) and improved the liver dysfunction parameters by the significant decrease of gamma-glytamyl transferase (GGT), phosphatases alkalines (PAL), lactate deshydrogenase (LDH) and aspartate and lactate transaminases (AST and ALT) activities which increased in diabetic rats. Moreover, 17 beta-estradiol treatment in diabetic rats protects against alloxan-induced pancreatic beta-cells and hepatic cells damages. 相似文献
993.
The solubility of maltitol in pure water and industrial syrup was measured in a temperature range from 10 to 90 °C. Maltitol
is highly soluble in water, and this yields high viscosity values for the saturated aqueous solutions at different temperatures.
In addition, solubility of maltitol in ethanol/water mixtures was followed at 30, 35, 45, and 55 °C. Results show that maltitol
solubility is highly dependent on water content in the solvent mixture. Moreover, it increases monotonically with temperature.
The logarithm of viscosity changes linearly against the mole fraction of maltitol in the aqueous solutions up to saturation.
The saturated solutions showed a Newtonian behavior in a temperature range from 20 to 90 °C. Maltitol is also characterized
in supersaturated solutions by a narrow metastable zone, which slightly increases as temperature is raised. The density of
aqueous solutions of maltitol was measured as a function of molality up to saturation at 20 °C, and results show that density
can be correlated with concentration according to a linear relation. The obtained results were used to explain maltitol crystallization,
which exhibits a high nucleation rate and a slow growth leading to small size crystals. 相似文献
994.
Role of nitric oxide in D-galactosamine-induced cell death and its protection by PGE1 in cultured hepatocytes. 总被引:1,自引:0,他引:1
Emilio Siendones Dalia Fouad Amira Mohamed Kamal ElSaid Abou-Elella Ana Quintero Pilar Barrera Jordi Muntané 《Nitric oxide》2003,8(2):133-143
Prostaglandin E(1) (PGE(1)) reduces cell death in experimental and clinical manifestations of liver dysfunction. Nitric oxide (NO) has been shown to exert a protective or noxious effect in different experimental models of liver injury. The aim of the present study was to investigate the role of NO during PGE(1) protection against D-galactosamine (D-GalN) citotoxicity in cultured hepatocytes. PGE(1) was preadministered to D-GalN-treated hepatocytes. The role of NO in our system was assessed by iNOS inhibition and a NO donor. Different parameters related to apoptosis and necrosis, NO production such as nitrite+nitrate (NO(x)) release, iNOS expression, and NF-kappaB activation in hepatocytes were evaluated. The inhibition of iNOS reduced apoptosis induced by D-GalN in hepatocytes. PGE(1) protection against D-GalN injury was associated with its capacity to reduce iNOS expression and NO production induced by D-GalN. Nevertheless, iNOS inhibition showed that protection by PGE(1) was also mediated by NO. Low concentrations of a NO donor reduced D-GalN injury with a decrease in the extracellular NO(x) concentration. High concentrations of the NO donor enhanced NO(x) concentration and increased cell death by D-GalN. The present study suggests that low NO production induced by PGE(1) preadministration reduces D-GalN-induced cell death through its capacity to reduce iNOS expression and NO production caused by the hepatotoxin. 相似文献
995.
Hendrik Adams Walter Brummelhuis Bram Maassen Nathalie van Egmond Mohamed El Khattabi Frank Detmers Pim Hermans Branko Braam Jord Stam Theo Verrips 《Biotechnology and bioengineering》2009,104(1):143-151
Toxic‐shock syndrome is primarily caused by the Toxic‐shock syndrome toxin 1 (TSST‐1), which is secreted by the Gram‐positive bacterium Staphylococcus aureus. The toxin belongs to a family of superantigens (SAgs) which exhibit several shared biological properties, including the induction of massive cytokine release and Vβ‐specific T‐cell proliferation. In this study we explored the possibility to use monoclonal Variable domains of Llama Heavy‐chain antibodies (VHH) in the immuno capturing of TSST‐1 from plasma. Data is presented that the selected VHHs are highly specific for TSST‐1 and can be efficiently produced in large amounts in yeast. In view of affinity chromatography, the VHHs are easily coupled to beads, and are able to deplete TSST‐1 from plasma at very low, for example, pathologically relevant, concentrations. When spiked with 4 ng/mL TSST‐1 more than 96% of TSST‐1 was depleted from pig plasma. These data pave the way to further explore application of high‐affinity columns in the specific immuno depletion of SAgs in experimental sepsis models and in sepsis in humans. Biotechnol. Bioeng. 2009; 104: 143–151 © 2009 Wiley Periodicals, Inc. 相似文献
996.
997.
Elboutachfaiti Redouan Delattre Cedric Petit Emmanuel El Gadda Mohamed Courtois Bernard Michaud Philippe El Modafar Cherkaoui Courtois Josiane 《Carbohydrate research》2009,344(13):1670-1675
A new source for the production of bioactive glucuronic acid oligosaccharides (GlcUAOs) from the depolymerization of green seaweed Ulva lactuca glucuronan (Algal glucuronan) has been investigated. Algal glucuronan purification was optimized by the acidic precipitation method which allowed us to separate the polysaccharide mixture extracted from the cell wall of Ulva lactuca using hot water containing sodium oxalate. A series of the GlcUAOs were obtained by enzyme degradation of algal glucuronan with a glucuronan lyase (GL) isolated from Trichoderma strain. The putative bioactive GlcUAOs generated were then purified by size-exclusion chromatography in gram quantity and characterized by 1H/13C NMR spectroscopy and ESI-Q/TOF-mass spectrometry. 相似文献
998.
El Sayed H. El Ashry Ahmed A. Kassem Hamida M. Abdel-Hamid Farida Louis Mohamed R. Aouad 《Carbohydrate research》2009,344(6):725-733
The glycosylation of 5-(3-chlorobenzo[b]thien-2-yl)-4H-1,2,4-triazole-3-thiol (1) and its 3-benzylsulfanyl and 3-methylsulfanyl derivatives with different glycosyl halides 2-4 has been studied in presence of base. The S-glycosides 5-7 were obtained in the presence of triethylamine, whereas the respective S,N4-bis(glycosyl) derivatives 8-10 were synthesized in the presence of potassium carbonate; the S,N2-bis(glycosyl) isomer 11 could also be isolated in the case of the galactosyl analog. Similarly, after protecting 1 as 3-benzyl(methyl)sulfanyl derivatives 12 or 13, the N4-glycosyl analogs 14-19 as well as minor amounts of S,N2-bis(galactosyl) isomers 20 and 21 were formed. The theoretical calculations using AM1 semiempirical methods agreed with the experimental results. Microwave irradiation (MWI) led to higher yields in much less time than the conventional methods, and no change in regioselectivity has been noticed. 相似文献
999.
Joby J. Westmoreland Qian Wang Mohamed Bouzaffour Suzanne J. Baker 《Developmental biology》2009,334(1):285-115
The formation of adequate masses of endocrine and exocrine pancreatic tissues during embryogenesis is essential to ensure proper nutrition and glucose homeostasis at postnatal stages. We generated mice with pancreas-specific ablation of the 3-phosphoinositide-dependent protein kinase 1 (Pdk1) to investigate how signaling downstream of the phosphatidylinositol-3-OH kinase (PI3K) pathway controls pancreas development. Pdk1-conditional knock-out mice were born with conspicuous pancreas hypoplasia, and within a few weeks, they developed severe hyperglycemia. Our detailed characterization of the mutant embryonic pancreas also revealed distinct temporal, cell type-specific requirements of Pdk1 activity in the control of cell proliferation, cell survival, and cell size during pancreas development. These results thus uncover Pdk1 as a novel, crucial regulator of pancreatic growth during embryogenesis. In addition, we provide evidence that Pdk1 activity is required differently in mature pancreatic cell types, since compensatory proliferation and possible mTORC2 activation occurred in exocrine cells but not in β cells of the Pdk1-deficient postnatal pancreas. 相似文献
1000.
Amal M. Mohamed Tarek F. Elwakil Ibrahim M. Taher Mohamed M. Elbarbary Hesham F. Kayed Hassan A. Hussein Ola M. Eid 《Cell and tissue research》2009,338(1):107-115
Cyclin D1 gene amplification has been reported to promote abnormal endothelial cell proliferation and angiogenesis; these
findings constantly present in proliferating haemangiomas. The present study was conducted to evaluate cyclin D1 gene amplification
by fluorescence in situ hybridization analysis in tissue biopsies of 22 proliferating haemangiomas from 20 infants. Two significant
correlations of cyclin D1 gene amplification with the early onset and the duplication of proliferating haemangiomas have been
observed. Moreover, a significant correlation (P≤0.05) has been found between the treatment parameters of proliferating haemangiomas with the amplified versus the normal
cyclin D1 gene. Proliferating haemangiomas with the amplified cyclin D1 gene required more frequent flashlamp pulsed dye laser
treatment sessions at the maximum dosimetry and more frequent intralesional steroid injections at the maximum dose/injection
but treatment outcomes were limited. The more frequent post-treatment complications among proliferating haemangiomas with
cyclin D1 gene amplification might be attributable not only to the associated more aggressive natural course, but also to
the higher treatment parameters needed for effective treatment. Within the limitations of the present study, cyclin D1 gene
amplification was seen for the first time in proliferating haemangiomas. We have found that the amplification of the cyclin
D1 gene can predict the more aggressive natural course of proliferating haemangiomas and the limited outcome and higher incidence
of complications after non–excision treatment modalities. The present findings reflect the possible usefulness of antisense
cyclin D1 to improve the therapeutic outcome of proliferating haemangiomas. 相似文献