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61.
Large-scale protein annotation through gene ontology 总被引:1,自引:0,他引:1
Xie H Wasserman A Levine Z Novik A Grebinskiy V Shoshan A Mintz L 《Genome research》2002,12(5):785-794
62.
Fidder HH Olschwang S Avidan B Zouali H Lang A Bardan E Picard O Bar-Meir S Colombel JF Chowers Y 《American journal of medical genetics. Part A》2003,(3):240-244
Ulcerative colitis (UC) and Crohn's disease (CD) are heterogeneous disorders characterized by chronic intestinal inflammation. Genetic predisposition is a major risk factor in both diseases. The CARD15 (NOD2) gene has been implied as a candidate gene in the pathogenesis CD. Our aim was to delineate the frequency of three missense and one frameshift variant of CARD15 in Israeli Jewish CD and UC patients. DNA was extracted from blood samples from 238 unrelated inflammatory bowel disease (IBD) patients, 68 with UC and 170 with CD. The DNA was genotyped for two missense mutations, R675W and G881R, and one frameshift mutation, 980FS981X. Mutations in CARD15 were observed with significantly greater frequency in CD patients (46/170, 27%) than in UC patients (7/68, 10%) (P = 0.005). Homozygous and compound heterozygous carriers were restricted to seven (4%) patients with CD as compared to none of the UC patients (P = 0.01). Similar rates in Ashkenazi and non-Ashkenazi Jewish patients were observed. Age-of-onset of disease was lower in Ashkenazi mutation carriers as compared to non-carriers of Ashkenazi origin (18.7 +/- 8.6 years vs. 25.8 +/- 13.4 years, respectively, P = 0.03). No other phenotypic characteristics could distinguish mutation carriers from non-carriers. We conclude that germline mutations in the CARD15 gene are more frequently found in CD than UC patients and appear to predict an earlier age-of-onset in Ashkenazi Jewish patients. No association could be demonstrated between CARD15 mutations and specific disease course or behavior. 相似文献
63.
Farkash-Amar S Lipson D Polten A Goren A Helmstetter C Yakhini Z Simon I 《Genome research》2008,18(10):1562-1570
64.
Kedem A Hourvitz A Fisch B Shachar M Cohen S Ben-Haroush A Dor J Freud E Felz C Abir R 《Journal of assisted reproduction and genetics》2011,28(9):761-769
Purpose
To compare macroporous alginate scaffolds with Matrigel for culturing frozen-thawed human primordial follicles in organ culture. 相似文献65.
Intercellular adhesion molecule (ICAM)-2 is highly expressed on platelets and endothelium and is a counter-receptor for the leukocyte integrin, lymphocyte function-associated antigen-1 (LFA-1) and for the dendritic cell-specific, ICAM-grabbing non-integrin (DC-SIGN) protein. In this study, we investigated structural and functional differences between ICAM-2 from platelets and that from endothelial cells. The isoelectric point (pI) of ICAM-2 from HUVEC was pH 3.5-4.3, whereas that of platelet ICAM-2 was more acidic at pH 3.0-3.7. This charge difference was abolished by treatment with N-glycanase or neuraminidase, thus it was due to cell-specific N-linked glycosylation. Purified, immobilized platelet ICAM-2 supported 50% less adhesion of LFA-1-bearing T cells than did purified HUVEC ICAM-2 and no adhesion was observed of monocyte-derived immature dendritic cells via DC-SIGN to platelet ICAM-2. Treatment of platelet ICAM-2 with neuraminidase abolished these functional differences. These findings demonstrated that physiologic sialylation of platelet ICAM-2 renders it less able than endothelial ICAM-2 to support adherence of leukocytes. 相似文献
66.
67.
A mechanism of ubiquitin-independent proteasomal degradation of the tumor suppressors p53 and p73 总被引:4,自引:0,他引:4 下载免费PDF全文
Protein degradation is an essential and highly regulated process. The proteasomal degradation of the tumor suppressors p53 and p73 is regulated by both polyubiquitination and by an ubiquitin-independent process. Here, we show that this ubiquitin-independent process is mediated by the 20S proteasomes and is regulated by NQO1. NQO1 physically interacts with p53 and p73 in an NADH-dependent manner and protects them from 20S proteasomal degradation. Remarkably, the vast majority of NQO1 in cells is found in physical association with the 20S proteasomes, suggesting that NQO1 functions as a gatekeeper of the 20S proteasomes. We further show that this pathway plays a role in p53 accumulation in response to ionizing radiation. Our findings provide the first evidence for in vivo degradation of p53 and p73 by the 20S proteasomes and its regulation by NQO1 and NADH level. 相似文献
68.
Lymphocyte arrest requires instantaneous induction of an extended LFA-1 conformation mediated by endothelium-bound chemokines 总被引:11,自引:0,他引:11
Shamri R Grabovsky V Gauguet JM Feigelson S Manevich E Kolanus W Robinson MK Staunton DE von Andrian UH Alon R 《Nature immunology》2005,6(5):497-506
It is widely believed that rolling lymphocytes require successive chemokine-induced signaling for lymphocyte function-associated antigen 1 (LFA-1) to achieve a threshold avidity that will mediate lymphocyte arrest. Using an in vivo model of lymphocyte arrest, we show here that LFA-1-mediated arrest of lymphocytes rolling on high endothelial venules bearing LFA-1 ligands and chemokines was abrupt. In vitro flow chamber models showed that endothelium-presented but not soluble chemokines triggered instantaneous extension of bent LFA-1 in the absence of LFA-1 ligand engagement. To support lymphocyte adhesion, this extended LFA-1 conformation required immediate activation by its ligand, intercellular adhesion molecule 1. These data show that chemokine-triggered lymphocyte adhesiveness involves a previously unrecognized extension step that primes LFA-1 for ligand binding and firm adhesion. 相似文献
69.
Farfel A Assa A Amir I Bader T Bartal C Kreiss Y Sagi R 《European journal of pediatrics》2011,170(4):519-525
On January 12 2010, a 7.0-magnitude earthquake struck Haiti. The region had suffered an estimated 316,000 fatalities with
approximately 300,000 injured and more than 1 million people who lost their houses. Following the quake, the Israeli Defense
Force Medical Corps dispatched a field hospital unit to the capital city, Port au Prince. The hospital had a pediatric division
which included pediatric emergency department, pediatric ward and neonatal unit. We elaborate on the various aspects of pediatric
treatment that was provided by our hospital. A total of 363 pediatric patients (younger than 18 years) were admitted to our
facility during its 10 days of operation. Out of this total, 272 pediatric patients were treated by the pediatric division,
79 (29%) were hospitalized and 57 (21%) required surgery. The pediatric team included seven pediatricians, one pediatric surgeon
and six registered nurses. An electronic record and a hard copy file were created for each patient. Fifty-seven percent of
the children presented with direct earthquake related injuries. Twelve patients required resuscitation and stabilization and
three patients had died. The majority of injuries were orthopedic while infectious diseases accounted for most of the general
pediatric diagnoses. In conclusion, operating a field hospital for a population affected by natural disaster is a complex
mission. However, pediatric care has its own unique, challenging characteristics. 相似文献
70.
Glutamatergic inputs clustered over approximately 20-40 microm can elicit local N-methyl-D-aspartate (NMDA) spike/plateau potentials in terminal dendrites of cortical pyramidal neurons, inspiring the notion that a single terminal dendrite can function as a decision-making computational subunit. A typical terminal basal dendrite is approximately 100-200 microm long: could it function as multiple decision-making subunits? We test this by sequential focal stimulation of multiple sites along terminal basal dendrites of layer 5 pyramidal neurons in rat somatosensory cortical brain slices, using iontophoresis or uncaging of brief glutamate pulses. There was an approximately sevenfold spatial gradient in average spike/plateau amplitude measured at the soma, from approximately 3 mV for distal inputs to approximately 23 mV for proximal inputs. Spike/plateaus were NMDA receptor (NMDAR) conductance-dominated at all locations. Large Ca(2+) transients accompanied spike/plateaus over a approximately 10- to 40-microm zone around the input site; smaller Ca(2+) transients extended approximately uniformly to the dendritic tip. Spike/plateau duration grew with increasing glutamate and depolarization; high Ca(2+) zone size grew with spike/plateau duration. The minimum high Ca(2+) zone half-width (just above NMDA spike threshold) increased from distal (approximately 10 microm) to proximal locations (approximately 25 microm), as did the NMDA spike glutamate threshold. Depolarization reduced glutamate thresholds. Simulations exploring multi-site interactions based on this demonstrate that if appropriately timed and localized inputs occur in vivo, a single basal dendrite could correspond to a cascade of multiple co-operating dynamic decision-making subunits able to retain information for hundreds of milliseconds, with increasing influence on neural output from distal to proximal. Dendritic NMDA spike/plateaus are thus well-suited to support graded persistent firing. 相似文献