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21.
S. T. Chandel H. S. Gaur M. M. Alam 《Archives Of Phytopathology And Plant Protection》2013,46(3):195-200
The effects of puddling and water regimes on hydraulic conductivity (cm/day) of soil and on bulk density (mg/m 3 ) during rice culture, soil physical characteristics of the experimental field population densities of plant-parasitic nematodes have been studied. Puddling reduced the bulk density of soil and decreased the hydraulic conductivity in the upper layers but not in the deeper layers of soil aeration was reduced due to high moisture levels retained in the puddled soil. Population density of M. triticoryzae declined in puddled soil. The invasion of the roots by the second-generation infective juveniles was reduced. The population density of the root-knot nematodes was higher in the non-puddled soil especially in unsubmerged condition compared to puddled and submerged soil. However, if the seedlings were already infected before transplanting and submergence, the nematode could survive well and reproduce within the aerenchyma of the root. 相似文献
22.
S. T. Chandel H. S. Gaur M. M. Alam 《Archives Of Phytopathology And Plant Protection》2013,46(4):287-290
Abstract Horsfall, J. G. (Ed.): Annual Review of Phytopathology. Vol. 4. VII + 423 S. Palo Alto, 1966: Annual Reviews, Inc. Leinen, 9,00 $. Reviewed by K. Naumann. Gregory, P. H. und Monteith, J. L. (Ed.): Airborne microbes. Seventeenth Symposium of the Society for General Microbiology held at the Imperial College, London April 1967. XII + 385 S., mit Abb. u. Tab. London, 1967: Cambridge University Press, Leinenrücken, 75 s. Reviewed by H. J. Müller. Raper, J. R.: Genetics of sexuality in higher fungi. VIII + 283 S., mit Abb. u. Tab., New York, 1966: The Ronald Press Company, Leinen, 12,00 $. Reviewed by M. Schmiedeknecht. Albrecht, F. O.: Polymorphisme phasaire et biologie des acridiens migrateurs. X + 194 S., 52 Abb. Paris, 1967: Masson et Cie, Éditeurs, karton., 50 F. Reviewed by R. Fritzsche. Wigglesworth, V. B.: Insect physiology. VII + 134 S., 12 Abb., London, 1966: Methuen &; Co Ltd., brosch., 10 s 6 d. Reviewed by G. Schäller. Machlis, L. (Ed.): Annual Review of Plant Physiology. Vol. 18. VIII + 480 S., mit Abb. u. Tab., Palo Alto, Ca., 1967: Annual Reviews, Inc., Leinen, 9,00 $. Reviewed by H. Wolffgang. Newton, B. A. und Reynolds, P. E. (Ed.): Biochemical studie of antimicrobial drugs. (Sixteenth symposium of the Society for General Microbiology held at the Royal Institution, London, April 1966). X + 349 S., mit Abb. u. Tab., London, 1966: Cambridge University Press, Halbleinen, 60 s. Reviewed by H. J. Müller. Pilet, P.-É.: La cellule, structure et fonctions. 406 S., 310 Abb.; 32 ganzs. Abb., Paris 1966: Schwarz-Weiß-Tafeln. Masson et Cie, Editeurs, brosch. 38 F. Reviewed by K. Schmelzer. Ciba (Ed.): Dimecron 257 S. Basle, Switzerland, 1967: P.O. Box — CIBA — Kunststoff Reviewed by Horst Beitz. Bellamy, L. J.: Ultrarot-Spektrum und chemische Konstitution. 2. Auflage, 325 S., 11 Abb., 23 Tab. Darmstadt, 1966: Dr. Dietrich Steinkopff Verlag, kart., 28,— DM Reviewed by Volker Müller. Bahr, G. F.; Zeitler, E. H. (Ed.): Quantitative electron microscopy. 1965, VIII + 605 (1340) S., mit Abb. u. Tab., Leinen, 16,00 $, Baltimore (Md.), The Williams &; Wilkins Company. Reviewed by H. B. Schmidt. 相似文献
23.
24.
Singhal P Gaur A Behl V Gautam A Varshney B Paliwal J Batra V 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,852(1-2):293-299
A simple, sensitive and rapid liquid chromatography/tandem mass spectrometric (LC-MS/MS) method was developed and validated for quantification of chloroquine, an antimalarial drug, in plasma using its structural analogue, piperazine bis chloroquinoline as internal standard (IS). The method is based on simple protein precipitation with methanol followed by a rapid isocratic elution with 10 mM ammonium acetate buffer/methanol (25/75, v/v, pH 4.6) on Chromolith SpeedROD RP-18e reversed phase chromatographic column and subsequent analysis by mass spectrometry in the multiple reaction monitoring mode (MRM). The precursor to product ion transitions of m/z 320.3-->247.2 and m/z 409.1-->205.2 were used to measure the analyte and the IS, respectively. The assay exhibited a linear dynamic range of 2.0-489.1 ng/mL for chloroquine in dog plasma. The limit of detection (LOD) and lower limit of quantification (LLOQ) were 0.4 and 2.0 ng/mL, respectively in 0.05 mL plasma. Acceptable precision and accuracy were obtained for concentrations over the standard curve range of 2.0-489.1 ng/mL. A run time of 2.0 min for a sample made it possible to achieve a throughput of more than 400 plasma samples analyzed per day. The validated method was successfully used to analyze samples of dog plasma during non-clinical study of chloroquine. 相似文献
25.
Xia Zhao Zhiwen Zeng Uma Gaur Jiankang Fang Tangming Peng Shuai Li Wenhua Zheng 《Journal of cellular physiology》2019,234(9):16619-16629
Metformin, a first line anti type 2 diabetes drug, has recently been shown to extend lifespan in various species, and therefore, became the first antiaging drug in clinical trial. Oxidative stress due to excess reactive oxygen species (ROS) is considered to be an important factor in aging and related disease, such as Alzheimer's disease (AD). However, the antioxidative effects of metformin and its underlying mechanisms in neuronal cells is not known. In the present study, we showed that metformin, in clinically relevant concentrations, protected neuronal PC12 cells from H2O2-induced cell death. Metformin significantly ameliorated cell death due to H2O2 insult by restoring abnormal changes in nuclear morphology, intracellular ROS, lactate dehydrogenase, and mitochondrial membrane potential induced by H2O2. Hoechst staining assay and flow cytometry analysis revealed that metformin significantly reduced the apoptosis in PC12 cells exposed to H2O2. Western blot analysis further demonstrated that metformin stimulated the phosphorylation and activation of AMP-activated protein kinase (AMPK) in PC12 cells, while application of AMPK inhibitor compound C, or knockdown of the expression of AMPK by specific small interfering RNA or short hairpin RNA blocked the protective effect of metformin. Similar results were obtained in primary cultured hippocampal neurons. Taken together, these results indicated that metformin is able to protect neuronal cells from oxidative injury, at least in part, via the activation of AMPK. As metformin is comparatively cheaper with much less side effects in clinic, our findings support its potential to be a drug for prevention and treatment of aging and aging-related diseases. 相似文献
26.
Gold containing Ayurvedic preparation, Swarna Vasant Malti, was given to 20 male persons in a dose of 100 mg twice a day for 40 days under supervision of Ayurvedic physicians. The total cumulative intake of 160 mg of gold at the rate of 4 mg per day in this form did not have any toxic effect on human body as evidenced by clinical examination, unaltered body weight, absence of urinary pathology and by 30 sensitive biochemical and enzymatic tests. The gold from this Ayurvedic preparation was found in plasma and erythrocytes, excreted partly in urine and was present in semen. Gold binding to albumin and hemoglobin slightly increased their electrophoretic mobility towards anode. This gold preparation seemed to increase sperm motility and prostatic activity. 相似文献
27.
Sengupta K Banerjee S Saxena NK Jonathan NB Campbell DR Banerjee SK 《Molecular and cellular biochemistry》2004,262(1-2):215-224
Beta-estradiol (17beta-E2) augments VEGF-A expression in various estrogen targeted organs and cells including breast tumor derived cell lines, via an ER-alpha mediated pathway. Ironically, 17beta-E2 is able to regulate some genes via ER-alpha independent pathways. In the present study, we sought to determine whether 17beta-E2 can modulate VEGF-A expression in absence of ER-alpha, and therefore, three different cell lines including ER-alpha+ MCF-7, and ER-alpha SKBR-3 and HMEC were used for this study. The present study demonstrates that 17beta-E2 also induces VEGF-A mRNA expression in ER-negative SKBR-3 breast tumor cells in a manner similar to that observed in ER-positive MCF-7 cells. Blocking the induced-expression by antiestrogen ICI 182,780 indicates the induction pathway is ER dependent. While ER-alpha mRNA is absent in both HMEC and SKBR-3 cells, the impact of estrogen was found only in SKBR-3 cells, suggesting the existence of an analogue to ER-alpha or overlapping signal in these cells. Consistent with this suggestion, the present studies demonstrate the existence of an ER-alpha(var2) protein in MCF-7 and in SKBR-3 cells. This variant is predominantly localized in the nuclei of SKBR-3 cells. Importantly, specific binding of 17beta-E2 by these cells suggest the ER-alpha(var2) may act as active receptor in SKBR-3 cells. 相似文献
28.
The Wnt antagonist secreted frizzled-related protein-1 is a negative regulator of trabecular bone formation in adult mice 总被引:18,自引:0,他引:18
Bodine PV Zhao W Kharode YP Bex FJ Lambert AJ Goad MB Gaur T Stein GS Lian JB Komm BS 《Molecular endocrinology (Baltimore, Md.)》2004,18(5):1222-1237
Previous studies have associated activation of canonical Wnt signaling in osteoblasts with elevated bone formation. Here we report that deletion of the murine Wnt antagonist, secreted frizzled-related protein (sFRP)-1, prolongs and enhances trabecular bone accrual in adult animals. sFRP-1 mRNA was expressed in bones and other tissues of +/+ mice but was not observed in -/- animals. Despite its broad tissue distribution, ablation of sFRP-1 did not affect blood and urine chemistries, most nonskeletal organs, or cortical bone. However, sFRP-1-/- mice exhibited increased trabecular bone mineral density, volume, and mineral apposition rate when compared with +/+ controls. The heightened trabecular bone mass of sFRP-1-/- mice was observed in adult animals between the ages of 13-52 wk, occurred in multiple skeletal sites, and was seen in both sexes. Mechanistically, loss of sFRP-1 reduced osteoblast and osteocyte apoptosis in vivo. In addition, deletion of sFRP-1 inhibited osteoblast lineage cell apoptosis while enhancing the proliferation and differentiation of these cells in vitro. Ablation of sFRP-1 also increased osteoclastogenesis in vitro, although changes in bone resorption were not observed in intact animals in vivo. Our findings demonstrate that deletion of sFRP-1 preferentially activates Wnt signaling in osteoblasts, leading to enhanced trabecular bone formation in adults. 相似文献
29.
Upadhyay R Shukla A Gaur K 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2002,105(8):1215-1219
Four hybrids (4 F1s) were chosen out of crosses in the urdbean [Vigna mungo (L.) Hepper, 2n = 22] having contrasting morphological characters. Zymograms for isozyme peroxidase were drawn from the patterns obtained from parents and their respective F1 hybrids on the basis of relative similarities to parental bands. The selfed or crossed nature of hybrid pods was determined from the zymograms and their analysis. The number of bands and their intensities gave an idea about the extent of crossing in F1 populations. Genetic identity (I) values were indicative of their selfed nature. Dendrograms were constructed on the basis of genetic identity values to display the relative similarities between the populations. Analysis was based on individual pods to confirm their hybrid or selfed nature. Possible use of this technique for identification of F1 pods and elimination of selfed pods might be implemented to shorten the breeding operations during crossing. 相似文献
30.
Delivery of nucleic acid into mammalian cells by anthrax toxin 总被引:1,自引:0,他引:1
Gaur R Gupta PK Goyal A Wels W Singh Y 《Biochemical and biophysical research communications》2002,297(5):1121-1127
Gene delivery vehicles based on receptor-mediated endocytosis offer an attractive long-term solution as they might overcome the limitations of toxicity and cargo capacity inherent to many viral gene delivery systems. The protective antigen component of anthrax toxin bind to specific receptors and deliver lethal factor or edema factor into the cytosol of mammalian cells. The N-terminal 254 amino acids of LF (LF(1-254)) binds to PA and, when fused to heterologous proteins, delivers such proteins into the cytosol. However, so far no attempt has been made to use the anthrax toxin system for the intracellular delivery of DNA. In the present study, LF(1-254) of anthrax toxin was fused to the DNA-binding domain of GAL4 protein. The fusion protein (LF(254)-GAL4DBD) showed both PA binding as well as DNA-binding activity in solution. The complex of fusion protein with plasmid DNA containing a reporter gene (luciferase or green fluorescent protein) along with PA delivered plasmid DNA into the cytosol of COS-1 cells. These results suggest that anthrax toxin components can be used as a non-viral system for the efficient delivery of DNA into the cytosol of mammalian cells. 相似文献