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991.
Luangsa-Ard JJ Ridkaew R Mongkolsamrit S Tasanathai K Hywel-Jones NL 《Fungal biology》2010,114(9):739-745
A hypocrealean Coleoptera pathogen with characteristic part-spores, collected from Khao Yai National Park and Kaeng Krachan National Park in Thailand, is reported. The overall morphology was similar to Cordyceps barnesii, which is known from Sri Lanka, with ascospores disarticulating into four unusually long part-spores that were 30-40 μm long. This disarticulation and part-spore size is, so far, unique within Cordyceps sensu lato. The Thai material was identified with C. barnesii and its placement in the genus Ophiocordyceps was confirmed. Multigene analyses based on the ribosomal small subunit, RPB1 and RPB2 genes revealed the close relationship of the Thai material to Ophiocordyceps konnoana as well as O. ravenelii, O. superficialis, and O. nigrella (all of which have significantly smaller part-spores). However, Ophiocordyceps barnesii and these related species were all characterised by dark-brown to purplish stromata and an affinity for melolonthid larval hosts. No anamorph was seen in the field and was not produced in the slow-growing cultures. 相似文献
992.
Christopher J Bulpitt Ruth Peters Jan A Staessen Lutgarde Thijs Marie-Christine De Vernejoul Astrid E Fletcher Nigel S Beckett 《Trials》2006,7(1):1-6
Background
Chronic pancreatitis is an inflammatory disease which is characterized by an irreversible conversion of pancreatic parenchyma to fibrous tissue. Beside obstructive jaundice and pseudocyst formation, about half of the patients need surgical intervention due to untreatable chronic pain during the course of the disease. In most of the patients with chronic pancreatitis, the head of the pancreas is the trigger of the chronic inflammatory process. Therefore, resection of pancreatic head tissue must be the central part of any surgical intervention. However, it is unclear to which extent the surgical procedure must be radical in order to obtain a favourable outcome for the patients.Design
A single centre randomized controlled, superiority trial to compare two techniques of duodenum preserving pancreatic head resection. Sample size: 65 patients will be included and randomized intraoperatively. Eligibility criteria: All patients with chronic pancreatitis and indication for surgical resection and signed informed consent. Cumulative primary endpoint (hierarchical model): duration of surgical procedure, quality of life after one year, duration of intensive care unit stay, duration of hospital stay. Reference treatment: Resection of the pancreatic head with dissection of the pancreas from the portal vein and transsection of the gland (Beger procedure). Intervention: Partial Resection of the pancreatic head without transsection of the organ and visualization of the portal vein (Berne procedure). Duration: September 2003-October 2007.Organisation/responsibility
The trial is conducted in compliance with the protocol and in accordance with the moral, ethical, regulatory and scientific principles governing clinical research as set out in the Declaration of Helsinki (1989) and the Good Clinical Practice guideline (GCP). The Center for Clinical Studies of the Department of Surgery Heidelberg is responsible for planning, conducting and final analysis of the trial. 相似文献993.
Pharoah DS Varsani H Tatham RW Newton KR de Jager W Prakken BJ Klein N Wedderburn LR 《Arthritis research & therapy》2006,8(2):R50-11
This study focuses upon three chemokines, namely CCL5, CXCL10 and CCL3, which are potential novel therapeutic targets in arthritis.
The aim of the study was to analyse the expression and production of these three chemokines within the joints of children
with juvenile idiopathic arthritis (JIA) of the oligoarticular and polyarticular subtypes. All three of these chemokines are
highly expressed at the level of mRNA, with the most significant increase in mRNA levels being demonstrated for CCL5 when
compared with matched peripheral blood samples and controls. We show that high levels of all three chemokines are present
in synovial fluid of children with JIA. We investigate the major source of CCL5 from inflammatory synovial cells, which we
show to be CD8+ T cells. This CD8+ synovial T cell population has an unexpected phenotype that has not been described previously,
being CCR7- yet predominantly CD28+ and CD45RA-. These cells contain high levels of stored intracellular CCL5, and rapid release
of CCL5 takes place on T cell stimulation, without requiring new protein synthesis. In addition, we demonstrate that CCL5
is present in synovial biopsies from these patients, in particular on the endothelium of small and medium sized vessels. We
believe this to be the first in depth analysis of these mediators of inflammation in JIA. 相似文献
994.
Mann NI Barker FK Graves JA Dingess-Mann KA Slater PJ 《Molecular phylogenetics and evolution》2006,40(3):750-759
Wrens of the genus Thryothorus comprise over a third of the species diversity in the family Troglodytidae. In addition to this species diversity, these wrens vary in a number of behavioral characteristics, in particular in the presence and structure of vocal duets, which makes them an interesting target for comparative evolutionary ecological and behavioral study. However, no phylogenetic hypothesis for this group-which would provide a sound basis for comparative analysis-is currently available. While previous molecular phylogenetic work established conclusively that the type of this genus, Thryothorus ludovicianus (Latham), was not part of a monophyletic group with other Thryothorus, the exact limits of the genus could not be established due to limited taxon sampling. Here, we present molecular data from all but four currently recognized species of Thryothorus. These data confirm that Thryothorus is paraphyletic, and that the type T. ludovicianus does not form a monophyletic group with any other member of the genus. Based on analyses of our data, we resurrect two previously recognized wren genera, Pheugopedius and Thryophilus, and erect a new genus-Cantorchilus-to house the remaining ex-Thryothorus species. Our hypothesis of relationships will provide a firm basis for future behavioral and morphological analyses of these species. 相似文献
995.
Rahim AA Taylor SL Bush NL ter Haar GR Bamber JC Porter CD 《The journal of gene medicine》2006,8(11):1347-1357
BACKGROUND: Ultrasound/microbubble-mediated gene delivery has the potential to be targeted to tissue deep in the body by directing the ultrasound beam following vector administration. Application of this technology would be minimally invasive and benefit from the widespread clinical experience of using ultrasound and microbubble contrast agents. In this study we evaluate the targeting ability and spatial distribution of gene delivery using focused ultrasound. METHODS: Using a custom-built exposure tank, Chinese hamster ovary cells in the presence of SonoVue microbubbles and plasmid encoding beta-galactosidase were exposed to ultrasound in the focal plane of a 1 MHz transducer. Gene delivery and cell viability were subsequently assessed. Characterisation of the acoustic field and high-resolution spatial analysis of transfection were used to examine the relationship between gene delivery efficiency and acoustic pressure. RESULTS: In contrast to that seen in the homogeneous field close to the transducer face, gene delivery in the focal plane was concentrated on the ultrasound beam axis. Above a minimum peak-to-peak value of 0.1 MPa, transfection efficiency increased as acoustic pressure increased towards the focus, reaching a maximum above 1 MPa. Delivery was microbubble-dependent and cell viability was maintained. CONCLUSIONS: Gene delivery can be targeted using focused ultrasound and microbubbles. Since delivery is dependent on acoustic pressure, the degree of targeting can be determined by appropriate transducer design to modify the ultrasound field. In contrast to other physical gene delivery approaches, the non-invasive targeting ability of ultrasound makes this technology an attractive option for clinical gene therapy. 相似文献
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