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991.
León-Sarmiento FE Prada DG Bayona-Prieto J Valderrama V García I León ME Sunnemark D 《Biomédica : revista del Instituto Nacional de Salud》2003,23(4):462-475
Trypanosoma cruzi, causative agent of Chagas disease, affects not only cardiac and intestinal structures but also neurological structures. A high prevalence of T. cruzi infection occurs in Colombia, prompting the present study. First, a qualitative metaanalysis was undertaken using the PubMed database, the electronic internet engine Altavista, Colombian journals indexed by Colciencias, and three relevant textbooks. The following key words were used: Trypanosoma, Chagas disease, nervous system, spinal cord, central nervous system, peripheral nervous system, neuromuscular junction, autonomic nervous system, muscle, muscle disorders, neuromuscular disease, neuromuscular disorders, synapticopathies and dysautonomia. The documents analyzed numbered 116 and included original papers, reviews, case reports, editorials, brief communications, conferences and book chapters. At minimum, each document included data involving ELISA testing, indirect immunofluorescense, or parasitemia levels in the clinical, serological or histopathological studies. Polymerase chain reaction (PCR) studies were not included because of the recent introduction of PCR as a confirmatory technique for Chagas disease in Colombia. Chagas disease affects the central, the peripheral and the autonomic nervous system in humans, although its effects on the antonomic system is most commonly investigated in Colombia. Neurological lesions must be evaluated carefully, because patients may be misdiagnosed and treated as carriers of 'idiopathic' diseases. Neurological pathologies poses a serious threat in Colombia due to the prevalence of Chagas disease. 相似文献
992.
Extracts of Phellinus linteus grown on germinated brown rice suppress liver damage induced by carbon tetrachloride in rats 总被引:4,自引:0,他引:4
Extracts of Phellinus linteus (EPB), grown on germinated brown rice, protected rats from liver injury induced by carbon tetrachloride (CCl4). Peroxidation products in the liver were decreased to 10% by EPB. Catalase and superoxide dismutase activities were significantly decreased to 55% and 39% by CCl4 administration, but EPB blocked this effect, resulting in enzyme activities at control levels. Expression of cytochromeP450 2E1 (CYP2E1) protein was significantly decreased to 88% in CCl4-treated rats but remained at control levels when EPB was also administered. EPB did not affect the altered fatty acid composition induced by CCl4. The hepatoprotective effect of EPB may be mediated by EPB's prevention of CCl4-induced CYP2E1 degradation. 相似文献
993.
994.
Membrane inlet mass spectrometry indicated massive light-dependent cycling of inorganic carbon between the medium and the
cells of various phytoplankton species representing the main groups of aquatic primary producers. These included diatoms,
symbiotic and free living dinoflagellates, a coccolithophorid, a green alga and filamentous and single cell cyanobacteria.
These organisms could maintain an ambient CO2 concentration substantially above or below that expected at chemical equilibrium with HCO3
−. The coccolithophorid Emiliania huxleyishifted from net CO2 uptake to net CO2 efflux with rising light intensity. Differing responses of CO2 uptake and CO2 fixation to changing light intensity supported the notion that these two processes are not compulsorily linked. Simultaneous
measurements of CO2 and O2 exchange and of the fluorescence parameters in Synechococcus sp. strain PCC 7942, showed that CO2 uptake can serve as a sensitive probe of the energy status of the photosynthetic reaction centers. However, during transitions
in light intensity, changes in CO2 uptake did not accord with those expected from fluorescence change. Quantification of the net fluxes of CO2, HCO3
− and of photosynthesis at steady-state revealed that substantial HCO3
− efflux accompanied CO2 uptake and fixation in the case of `CO2 users'. On the other hand, `HCO3
− users' were characterized by a rate of net CO2 uptake below that of CO2 fixation. The results support the notion that entities associated with the CCM function not only in raising the CO2 concentration at the site of Rubisco; they may also serve as a means of diminishing photodynamic damage by dissipating excess
light energy.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
995.
Mitochondrion is a vulnerable intracellular target to reactive oxygen species (ROS). ROS have been considered to be important regulators of the pathogenesis of pancreatitis. This study aims to determine whether ROS induces mitochondrial damage by monitoring the expression level of mitochondrial ATP synthase as the key molecular component in mitochondria associated with cellular damage. Pancreatic acinar AR42J cells were treated with cerulein which induces symptoms similar to that associated with human acute pancreatitis. Proteins were separated by two-dimensional electrophoresis using pH gradients of 5-8 and identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (MS), quadrupole time-of-flight MS and MS/MS with nano-electrospray. Following cerulein treatment, mitochondrial ATP synthase beta chain was highly expressed compared to nontreated cell. The protein was identified by its pI of 5.2 and molecular weight (56 354 Da) with 27 matched peptides. Among the MS spectrum, precursor ions m/z 488.28, 544.81, 631.82, 693.34, 718.38, 729.41, 801.40, 809.39, 825.94, and 994.52 were further identified using MS/MS and confirmed the isolated protein to be mitochondrial ATP synthase beta chain. In conclusion, cerulein-induced oxidative injury may result in the induction of mitochondrial ATP synthase, which may act as an adaptive pathophysiological process in the pancreas. 相似文献
996.
Human interleukin-2 (hIL-2) production in Escherichia coli and insect cell/baculovirus expression systems can be inefficient. Here we investigated secreted production of hIL-2 fused with green fluorescent protein (GFP) as a versatile fusion partner in optimized stably transfected insect Drosophila melanogaster S2 cells. This nonlytic S2 insect cell expression system employs a plasmid vector and allows for secretion of functional human proteins. We report that, following stable transfection and induction, S2 cells secreted hIL-2 as a fusion protein (approximately 2.3 microg/mL yield), with a secretion efficiency of approximately 90%. Regression analysis indicated a single linear relationship existed between GFP fluorescence and hIL-2 mass in both whole cell and secreted medium samples, indicating that in vivo monitoring and quantification of target foreign protein expression and even secretion is possible using this system. The simple comparative measurement of GFP fluorescence also allowed monitoring of secretion efficiency during periods of high GFP/hIL-2 expression. 相似文献
997.
An unstructured model was developed for batch cultivation of Corynebacterium lactofermentum (ATCC 21799) under controlled dissolved oxygen. The model is capable of predicting batch experiments performed at various initial substrate concentrations. By extending the batch culture model to a fed-batch model and using a heuristic approach to optimize the fed-batch cultivation, it is shown that fed-batch cultivation is superior to batch operation due to increased productivity at high substrate concentrations. 相似文献
998.
De Donato M Gallagher DS Lehn C Gill C Taylor JF 《Genetics and molecular research : GMR》2003,2(3):260-270
Seven genes were assigned by molecular cytogenetic methods to bovine chromosome 5. To accomplish this, specific primers were either publicly available or were designed from highly conserved regions of the publicly available mammalian gene sequences. The identity of the amplified segments was verified by sequencing and alignment with the published sequences. The optimized primers that amplified the desired bovine genes were used for screening a bovine bacterial artificial chromosome library. The positive clones were localized to a specific band of bovine chromosome 5 by fluorescence in situ hybridization. The genes HOXC4, SP1 and IGFBP6 were localized to band q21, COL2A1 was localized to bands q21-q23, IGF1 was localized to band q26, MB to band q31 and the gene CYP2D6 was localized to band q35. The cytogenetic assignment of SP1, IGFBP6, COL2A1, IGF1, MB and CYP2D6 is first reported here and the assignment of HOXC4 refines the previous assignment of this gene. The identification and localization of these genes further support the development of the human to bovine comparative map through characterizing the homologous segments conserved in the evolution of these species. This information will be useful for the future localization of genes that affect economically important traits in bovines. 相似文献
999.
Graham JE Douglas Boatwright J Hunskor MJ Howell DC 《Journal of strength and conditioning research / National Strength & Conditioning Association》2003,17(2):338-341
This study was conducted to evaluate the difference between active and passive recovery methods during successive suicide runs by Division I women's collegiate basketball athletes (n = 14). Testing consisted of sprinting suicides on the basketball court using both traditional (short) and reverse-sequence (long) protocols. Two 90-second recovery methods were used, passive (standing still) and active (slow self-paced jogging). Although successive run time was reduced by a mean of 0.55 seconds after passive recovery relative to active, it did not reach significance (p = 0.09). Likewise, the difference between long and short line versions was nonsignificant (p = 0.41). Therefore, neither line sequence nor 90-second recovery technique appears to influence subsequent run time when performing 2 maximal-effort suicides. 相似文献
1000.