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951.
Samples of foraged fruits from a former industrial site have been analyzed for potentially toxic elements (PTEs) (i.e., As, Cd, Cr, Cu, Ni, Pb, and Zn). The foraged fruit (blackberries, rosehips, and sloes) was gathered over two seasons along with samples of soil from the same sampling areas. All samples were acid digested, using a microwave oven, and then analyzed by inductively coupled plasma mass spectroscopy (ICP-MS). The concentration levels of the selected elements in foraged samples varied between not detectable limits and 24.6 μg/g (Zn). The soil-to-plant transfer factor was assessed for the PTEs. In all cases, the transfer values obtained were less than 1.00, indicating that the majority of the PTEs remains in the soil and that the uptake of PTEs from soil to plant at this site is not significant.  相似文献   
952.
《Biomarkers》2013,18(5):434-444
Damage to DNA by dopamine quinone and/or catechol estrogen quinones may play a significant role in the initiation of Parkinson’s disease (PD). Depurinating estrogen–DNA adducts are shed from cells and excreted in urine. The aim of this study was to discover whether higher levels of estrogen–DNA adducts are associated with PD. Forty estrogen metabolites, conjugates, and DNA adducts were analyzed in urine samples from 20 PD cases and 40 matched controls by using ultra performance liquid chromatography/tandem mass spectrometry. The levels of adducts in cases versus controls (P?<?0.005) suggest that unbalanced estrogen metabolism could play a causal role in the initiation of PD.  相似文献   
953.
Bacteriophages are the natural predators of bacteria and are available abundantly everywhere in nature. Lytic phages can specifically infect their bacterial host (through attachment to the receptor) and use their host replication machinery to replicate rapidly, a feature that enables them to kill a disease-causing bacteria. Hence, phage attachment to the host bacteria is the first important step of the infection process. It is reported in this study that the receptor could be an LPS which is responsible for the attachment of the Sfk20 phage to its host (Shigella flexneri 2a). Phage Sfk20 bacteriolytic activity was examined for preliminary optimization of phage titer. The phage Sfk20 viability at different saline conditions was conducted. The LC–MS/MS technique used here for detecting and identifying 40 Sfk20 phage proteins helped us to get an initial understanding of the structural landscape of phage Sfk20. From the identified proteins, six structurally significant proteins were selected for structure prediction using two neural network systems: AlphaFold2 and ESMFold, and one homology modeling software: Phyre2. Later the performance of these modeling systems was compared using various metrics. We conclude from the available and generated information that AlphaFold2 and Phyre2 perform better than ESMFold for predicting Sfk20 phage protein structures.  相似文献   
954.
Growth‐associated protein 43 (GAP‐43), a novel axonal phosphoprotein, is originally identified as a growth‐cone‐specific protein of developing neurons in vitro. The expression of GAP‐43 is also shown to be up‐regulated concomitant with increased synaptic plasticity in the brains in vivo, but how GAP‐43 is concerned with synaptic plasticity is not well understood. In the present study, therefore, we aimed to elucidate subcellular localization of GAP‐43 as culture development of rat hippocampal neurons. Western blotting showed that the expression of GAP‐43 in the cerebral and hippocampal tissues was prominently high at postnatal days 14 and 21 or the active period of synaptogenesis. Double‐labelling immunohistochemistry with an axonal marker Tau revealed that the immunoreactivity of GAP‐43 was seen throughout axons of cultured hippocampal neurons but stronger at axonal puncta of developing neurons than axonal processes. Double‐labelling immunohistochemistry with presynaptic terminal markers of synapsin and synaptotagmin revealed that the immunoreactivity of GAP‐43 was observed mostly at weak synapsin‐ and synaptotagmin‐positive puncta rather than strong ones. The quantitative analysis of immunofluorescent intensity showed a clear inverse correlation between GAP‐43 and either synapsin or synaptotagmin expression. These data indicate that GAP‐43 is highly expressed at immature growing axonal terminals and its expression is decreased along with the maturation of synaptogenesis. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
955.
Abstract

The consumption of fish and shellfish is a major route of human exposure to arsenic (As), because they contain relatively large concentrations of organoarsenicals, in particular arsenobetaine (AB). AB is considered non-toxic because of its rapid excretion from the human body. However, previous studies on human metabolism and excretion of AB have used the compound in solution rather than considering the effects that occur during the digestion of food in the gastrointestinal tract. In this preliminary study, we used microcosms inoculated with human faecal matter to investigate the aerobic and anaerobic degradation of AB by microorganisms associated with the large intestine. Samples were recovered over 30 days, centrifuged, filtered and the supernatant analysed for total As content and As speciation, using ICP–MS and HPLC–ICP–MS respectively. After 7 days the total As in the supernatants from the aerobic experiment fell to a minimum of 65% of the total added, recovering to 15% less than added after 30 days. By using anion and cation exchange chromatography coupled to ICP–MS detection, arsenobetaine (AB), dimethylarsinic acid (DMA), dimethylarsinoylacetic acid (DMAA) and trimethylarsine oxide (TMAO) were identified as degradation products. Results from the aerobic system showed that after 7 days incubation the AB had been degraded to DMA, DMAA and TMAO and after 30 days the degraded AB reappeared in the samples. The results for the anaerobic system showed no degradation of AB over the 30 day course of the experiment. These findings demonstrate for the first time that biocatalytic capability for AB degradation exists within the human gastrointestinal tract.  相似文献   
956.
The article examines the problem of the relationship between universal and specific forms of cultural–historical development of mental processes. From different methodological approaches, the author prefers an activity approach which emphasizes genetic primacy of external practical activity. This approach allows, according to the author, universality of internalization and at the same time ethnic uniqueness of mental processes. The article clarifies the problem of internalization through two practical examples: 1) the development of mental counting actions and 2) the process of human goal setting.  相似文献   
957.
A. Capuzzo 《Plant biosystems》2016,150(2):236-243
Hybridization of species belonging to the genus Mentha is quite common. However, the indicators of hybridity are many and make Mentha hybrids' identification difficult. By using the same molecular strategy that allowed us to unequivocally identify some Mentha species, we amplified the Not-Transcribed-Spacer (NTS) of the 5S-rRNA gene to characterize the industrial crop peppermint, M. × piperita and some important Mentha interspecific hybrids: M. × dalmatica, M. × dumetorum, M. × rotundifolia, M. × maximilianea, M. × smithiana, M. × verticillata, M. × villosa. DNA amplification, sequence and cluster analysis revealed differences in the 5S-rRNA NTS region of Mentha hybrids. Peppermint and all other hybrids were unequivocally discriminated by RFLP analysis by using TaqI restriction enzyme, while a further discrimination between M. × dumetorum and M. × verticillata was obtained by XhoI restriction enzyme. Essential oil composition showed clustering patterns similar to DNA fingerprint, with a clear discrimination between plants producing menthofuran (e.g. M. aquatica and its related hybrids, including peppermint) and those containing piperitenone oxide (M. longifolia and its related hybrids).  相似文献   
958.
The drug discovery and development processes are divided into different stages separated by milestones to indicate that significant progress has been made and that certain criteria for target validation, hits, leads and candidate drugs have been met. Proteomics is a promising approach for the identification of protein targets and biochemical pathways involved in disease process and thus plays an important role in several stages of the drug development. The blood–brain barrier is considered as a major bottleneck when trying to target new compounds to treat neurodegenerative diseases. Based on the survey of recent findings and with a projection on expected improvements, this report attempt to address how proteomics participates in drug development.  相似文献   
959.
Cuvillierinella salentina Papetti and Tedeschi, 1965 and its related species of the Rhapydioninidae family are widely distributed in the Western Mediterranean region by Campanian–Maastrichtian time. C. salentina, the type species of the genus, is studied in rich populations from its Italian type locality, and several other spots from Greece and Spain. It shows great variability: the well-known type coexists with streptospiral tests almost devoid of endoskeleton and wholly planispiral tests with fine mesh-like endoskeleton, as well as many intermediates. Such populations reflect the large capacity of evolution of at least the group of miliolids from which these populations are derived, if not the species itself. The genera Murciella and Cyclopseudedomia are probably the most direct offshoots, but other taxa appear to arise from this species or at least from the same stock of origin. In the same genus and at the same time (middle part of Campanian age, “CsB6a” zone), two new species are described, both hesitating between the streptospiral and planispiral coiling: – C. fluctuans nov. sp., from Greece, A tests being either streptospiral or planispiral, with primary and secondary chamberlets taking the aspect of polygonal isodiametric network and – C. perisalentina nov. sp., from Italy, with persistent streptospiral coiling and disordered arrangement of secondary chamberlets which allow us to consider its relation with species of the genus Pseudochubbina, hitherto of completely enigmatic origin. Assigned to the same genus, from Upper Campanian–Lower Maastrichtian time (“CsB6b” zone), C. aff. pylosensis, probably related to C. pylosensis, is studied from several populations, and constitutes, with the above mentioned species, what is called C. gr. salentina. Based on material from the CsB6b zone, the new genus Metacuvillierinella nov. gen. is introduced; M. decastroi nov. sp., type species of the new genus, known from Greece and Italy, shows characters common to C. gr. salentina, such as milioline to streptospiral nepionic coiling, large endoskeleton mesh, associated with some original characters, such as the unusual conjunction of the advolute coiling and absence of any final unrolling together with very low dimorphism of generation; this results in flat tests, often sigmoid shaped in axial section, very rare in the family. Thus, the genus Cuvillierinella, and especially C. salentina, appears as a possible source, or at least not far from the origin, of a number of taxa related to one another, constituting a large part of the Rhapydioninidae family. They are gathered together inside the new subfamily Cuvillierinellinae, distinct from the subfamily Rhapydionininae sensu stricto (comprising Rhapydionina and Fanrhapydionina) which makes a different and parallel branch, from Upper Campanian (CsB6b zone) to the end of Cretaceous time (CsB7 zone).  相似文献   
960.
Cardiorenal fibrosis is a biological process that increases with age and contributes to dysfunction of the heart and kidney. While numerous circulating and tissue hormones, cytokines and enzymes have been identified in the development of cardiorenal fibrosis, several reports have suggested that the anti-fibrotic natriuretic peptide system (NPS), pro-fibrotic renin–angiotensin–aldosterone system (RAAS), transforming growth factor-beta 1 (TGF-β1), matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinases (TIMPs) are fundamental regulators and mediators of this process. However, the simultaneous assessment of these components in the development of age-mediated cardiorenal fibrotic remodeling is not completely understood. Thus, we assessed cardiorenal structure and function, the circulating NPS and RAAS and the cardiorenal tissue gene expression of collagen (Col) I, Col III, TGF-β1, MMP-9 and TIMP-1 in 2 and 20 month old Fischer rats. Our studies determined that aging was characterized by an increase in cardiorenal fibrosis that was accompanied with cardiorenal dysfunction. These alterations were associated with lower circulating atrial and C-type natriuretic peptides and higher angiotensin II and aldosterone levels in the aged rats. Moreover, we observed a decrease in Col I and III and an increase in TIMP- mRNA expressions in the aged heart and kidney, while TGF-β1 expression increased and MMP-9 decreased only in the aged kidney. We conclude that the age-mediated alterations in these fibrotic regulator and mediator profiles favors collagen accumulation due to an imbalance between the NPS and RAAS as well as a decline in the degradative pathway, thus suggesting a therapeutic opportunity to target these components.  相似文献   
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