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991.
目的:探讨风湿性心脏病(以下简称风心病)合并妊娠剖宫产的麻醉处理及围术期的综合治疗。方法:对33例妊娠合并风心病剖宫产的临床资料进行回顾性分析。28例产妇选用腰麻-硬脊膜外联合麻醉(简称硬脊麻),2例选用硬膜外麻醉(简称硬外麻),1例因术前出现严重心衰及2例需同时行瓣膜置换+取栓术而行全身麻醉(全麻)。术前、术中积极防治心衰,对已行换瓣术后的产妇围术期合理应用抗凝剂。结果:麻醉过程多数平稳,新生儿除全麻的2例病例Apgar评分在2—3分外,其余均在8分以上,母婴均安全度过围手术期,无1例死亡。仅一例因宫腔出现活动性出血,止血效果差而行全宫切除术,余病例无出现围术期大出血危情。结论:硬脊麻用于风心病合并妊娠剖宫产手术是安全有效的,术前、术中积极正确地防治心衰、改善心功能等综合治疗及围术期合理应用抗凝剂,可降低母婴死亡率。 相似文献
992.
Improper protein folding (misfolding) can lead to the formation of disordered (amorphous) or ordered (amyloid fibril) aggregates.
The major lens protein, α-crystallin, is a member of the small heat-shock protein (sHsp) family of intracellular molecular
chaperone proteins that prevent protein aggregation. Whilst the chaperone activity of sHsps against amorphously aggregating
proteins has been well studied, its action against fibril-forming proteins has received less attention despite the presence
of sHsps in deposits found in fibril-associated diseases (e.g. Alzheimer’s and Parkinson’s). In this review, the literature
on the interaction of αB-crystallin and other sHsps with fibril-forming proteins is summarized. In particular, the ability
of sHsps to prevent fibril formation, their mechanisms of action and the possible in vivo consequences of such associations are discussed. Finally, the fibril-forming propensity of the crystallin proteins and its
implications for cataract formation are described along with the potential use of fibrillar crystallin proteins as bionanomaterials.
Received 13 June 2008; received after revision 29 July 2008; accepted 05 August 2008 相似文献
993.
Monocytes and their pathophysiological role in Crohn’s disease 总被引:1,自引:1,他引:0
Zhou L Braat H Faber KN Dijkstra G Peppelenbosch MP 《Cellular and molecular life sciences : CMLS》2009,66(2):192-202
Our immune system shows a stringent dichotomy, on the one hand displaying tolerance towards commensal bacteria, but on the
other hand vigorously combating pathogens. Under normal conditions the balance between flora tolerance and active immunity
is maintained via a plethora of dynamic feedback mechanisms. If, however, the balancing act goes faulty, an inappropriate
immune reaction towards an otherwise harmless intestinal flora causes disease, Crohn’s disease for example. Recent developments
in the immunology and genetics of mucosal diseases suggest that monocytes and their derivative cells play an important role
in the pathophysiology of Crohn’s disease. In our review, we summarize the recent studies to discuss the dual function of
monocytes - on the one hand the impaired monocyte function initiating Crohn’s disease, and on the other hand the overactivation
of monocytes and adaptive immunity maintaining the disease. With a view to developing new therapies, both aspects of monocyte
functions need to be taken into account.
Received 1 June 2008; received after revision 24 July 2008; accepted 13 August 2008 相似文献
994.
Autoimmune diseases are a leading cause of disability and are increasing in incidence in industrialized countries. How people
develop autoimmune diseases is not completely understood, but is related to an interaction between genetic background, environmental
agents, autoantigens and the immune response. Molecular mimicry continues to be an important hypothesis that explains how
an infection with an environmental agent results in autoimmune disease of the nervous system and other target organs. Although
molecular mimicry has yet to be unequivocally proven, in the past several years there has been a sharpening of its definition
with better experimental data implicating it as a cause of neurological disease in humans.
Received 9 July 2007; received after revision 15 November 2007; accepted 27 November 2007 相似文献
995.
Rosenstiel P Jacobs G Till A Schreiber S 《Cellular and molecular life sciences : CMLS》2008,65(9):1361-1377
NOD-like receptors (NLRs) comprise a family of cytosolic proteins that have been implicated as ancient cellular sentinels
mediating protective immune responses elicited by intracellular pathogens or endogenous danger signals. Genetic variants in
NLR genes have been associated with complex chronic inflammatory barrier diseases (e.g. Crohn disease, bronchial asthma). In
this review, we focus on the molecular pathophysiology of NLRs in the context of chronic inflammatory diseases and pinpoint
recent advances in the evolutionary understanding of NLR biology. We propose that the field of NLRs may serve as a prototype
for how a comprehensive understanding of an element of the immunological barrier will eventually lead to the development of
targeted diagnostic, therapeutic and/or preventive strategies.
Received 29 October 2007; received after revision 10 December 2007; accepted 19 December 2007 相似文献
996.
Parkinson’s disease (PD) is characterized by the death of dopaminergic neurons and the presence of Lewy bodies in the substantia
nigra pars compacta. The mechanisms involved in the death of neurons as well as the role of Lewy bodies in the pathogenesis
of the disease are still unclear. Lewy bodies are made of aggregated proteins, in which α-synuclein represents their major
component. α-Synuclein interacts with synphilin-1, a protein that is also present in Lewy bodies. When expressed in cells,
synphilin-1 forms inclusions together with α-synuclein that resemble Lewy bodies. Synphilin-1 is ubiquitylated by various
E3 ubiquitin-ligases, such as SIAH, parkin and dorfin. Ubiquitylation of synphilin-1 by SIAH is essential for its aggregation
into inclusions. We recently identified a new synphilin-1 isoform, synphilin-1A, that is toxic to neurons, aggregation-prone
and accumulates in detergent-insoluble fractions of brains from α-synucleinopathy patients. Synphilin-1A inclusions recruit
both α-synuclein and synphilin-1. Aggregation of synphilin-1 and synphilin-1A seems to be protective to cells. We now discuss
several aspects of the neurobiology and pathology of synphilin-1 isoforms, focusing on possible implications for PD.
Received 26 July 2007; received after revision 19 September 2007; accepted 15 October 2007 相似文献
997.
Double KL Dedov VN Fedorow H Kettle E Halliday GM Garner B Brunk UT 《Cellular and molecular life sciences : CMLS》2008,65(11):1669-1682
Neuromelanin and lipofuscin are two pigments produced within the human brain that, until recently, were considered inert cellular waste products of little interest to neuroscience. Recent research has increased our understanding of the nature and interactions of these pigments with their cellular environment and suggests that these pigments may, indeed, influence cellular function. The physical appearance and distribution of the pigments within the human brain differ, but both accumulate in the aging brain and the pigments share some structural features. Lipofuscin accumulation has been implicated in postmitotic cell aging, while neuromelanin is suggested to function as an iron-regulatory molecule with possible protective functions within the cells which produce this pigment. This review presents comparative aspects of the biology of neuromelanin and lipofuscin, as well as a discussion of their hypothesized functions in brain and their possible roles in aging and neurodegenerative disease. 相似文献
998.
Delgado M Pérez-Miguelsanz J Garrido F Rodríguez-Tarduchy G Pérez-Sala D Pajares MA 《Cellular and molecular life sciences : CMLS》2008,65(13):2080-2090
Wilson's disease is characterized by longterm hepatic accumulation of copper leading to liver disease with reduction of S-adenosylmethionine synthesis. However, the initial changes in this pathway remain unknown and constitute the objective of the present study. Using the Long Evans Cinnamon rat model, early alterations were detected in the mRNA and protein levels, as well as in the activities of several enzymes of the methionine cycle. Notably, the main change was a redox-mediated 80% decrease in the mRNA levels of the methionine adenosyltransferase regulatory subunit as compared to the control group. Moreover, changes in S-adenosylmethionine, S-adenosylhomocysteine, methionine and glutathione levels were also observed. In addition, in vitro experiments show that copper affects the activity and folding of methionine adenosyltransferase catalytic subunits. Taken together, these observations indicate that early copper accumulation alters methionine metabolism with a pattern distinct from that described previously for other liver diseases. 相似文献
999.
Sumoylation regulates diverse biological processes 总被引:8,自引:0,他引:8
Zhao J 《Cellular and molecular life sciences : CMLS》2007,64(23):3017-3033
Ten years after its discovery, the small ubiquitin-like protein modifier (SUMO) has emerged as a key regulator of proteins.
While early studies indicated that sumoylation takes place mainly in the nucleus, an increasing number of non-nuclear substrates
have recently been identified, suggesting a wider stage for sumoylation in the cell. Unlike ubiquitylation, which primarily
targets a substrate for degradation, sumoylation regulates a substrate’s functions mainly by altering the intracellular localization,
protein-protein interactions or other types of post-translational modifications. These changes in turn affect gene expression,
genomic and chromosomal stability and integrity, and signal transduction. Sumoylation is counter-balanced by desumoylation,
and well-balanced sumoylation is essential for normal cellular behaviors. Loss of the balance has been associated with a number
of diseases. This paper reviews recent progress in the study of SUMO pathways, substrates, and cellular functions and highlights
important findings that have accelerated advances in this study field and link sumoylation to human diseases.
Received 19 March 2007; received after version 16 July 2007; accepted 1 August 2007 相似文献
1000.
Nutrigenomics has the potential to tailor diets to optimize health, based on knowledge of key genetic polymorphisms. Identification
of candidate genes is often based on a priori knowledge of disease processes. However, genome-wide association methods are not only validating previously identified genes
and polymorphisms, but also revealing new gene-disease associations not anticipated from prior knowledge. In Crohn’s disease
(CD), such studies not only confirm the importance of caspase-activated recruitment domain 15 and major histocompatability
complex II molecules, but also reveal strong associations with the proinflammatory cytokine interleukin-23 receptor and autophagy-related
16-like gene. Genes identified to date in CD can be linked into two interrelated pathways: receptor-mediated cytokine induction
or autophagocytosis. New genomic technologies need to be matched with innovative methodologies to characterize the likely
impact of foods and to take the field to another dimension of value for human diet development and optimized health.
Received 2 July 2007; received after revision 31 July 2007; accepted 29 August 2007 相似文献