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131.
Mahito Sadaie Rafik Salama Thomas Carroll Kosuke Tomimatsu Tamir Chandra Andrew R.J. Young Masako Narita Pedro A. Pérez-Mancera Dorothy C. Bennett Heung Chong Hiroshi Kimura Masashi Narita 《Genes & development》2013,27(16):1800-1808
Senescence is a stress-responsive form of stable cell cycle exit. Senescent cells have a distinct gene expression profile, which is often accompanied by the spatial redistribution of heterochromatin into senescence-associated heterochromatic foci (SAHFs). Studying a key component of the nuclear lamina lamin B1 (LMNB1), we report dynamic alterations in its genomic profile and their implications for SAHF formation and gene regulation during senescence. Genome-wide mapping reveals that LMNB1 is depleted during senescence, preferentially from the central regions of lamina-associated domains (LADs), which are enriched for Lys9 trimethylation on histone H3 (H3K9me3). LMNB1 knockdown facilitates the spatial relocalization of perinuclear H3K9me3-positive heterochromatin, thus promoting SAHF formation, which could be inhibited by ectopic LMNB1 expression. Furthermore, despite the global reduction in LMNB1 protein levels, LMNB1 binding increases during senescence in a small subset of gene-rich regions where H3K27me3 also increases and gene expression becomes repressed. These results suggest that LMNB1 may contribute to senescence in at least two ways due to its uneven genome-wide redistribution: first, through the spatial reorganization of chromatin and, second, through gene repression. 相似文献
132.
133.
Masaho Okada Yuji Narita Yoshimori Araki Hideki Oshima Akihiko Usui Yuichi Ueda 《Journal of artificial organs》2013,16(2):164-169
Definitive endovascular techniques have been developed for pacemaker lead extraction; however, a few patients require immediate secondary open heart surgery because of incomplete transvenous lead extraction. This study examined the safety, effectiveness, and long-term outcome of the removal of cardiovascular implantable electronic device (CIED) via median sternotomy under cardiopulmonary bypass. The removal of CIED was performed in 6 patients (mean age 57 ± 16 years, 5 males and 1 female), from September 2000 to April 2011. The reasons for removal included eradication of an infection in 5 patients and elimination of pacemaker component allergy in 1. Positive culture results, including methicillin-sensitive Staphylococcus aureus (MSSA, n = 2), methicillin-resistant S. aureus (MRSA, n = 1), coagulase-negative staphylococci (CNS, n = 1), and methicillin-resistant S. epidermidis (MRSE, n = 1) were observed in all 5 infected patients. Mitral annuloplasty (n = 1), mitral valvuloplasty (n = 1), tricuspid annuloplasty (n = 3). Implantation of myocardial pacing leads (n = 5) were performed concomitantly (n = 4), or secondarily (n = 1). All 6 patients were alive in good condition at 72 ± 55 months following CIED removal. New device infection occurred in 1 patient during long-term follow up. Complete surgical removal of pacing systems via median sternotomy with cardiopulmonary bypass is, therefore, considered to be safe and feasible with acceptable long term results. 相似文献
134.
Yoko Shibata Shuichi Abe Sumito Inoue Akira Igarashi Keiko Yamauchi Yasuko Aida Hiroyuki Kishi Keiko Nunomiya Hiroshi Nakano Masamichi Sato Kento Sato Tomomi Kimura Takako Nemoto Tetsu Watanabe Tsuneo Konta Yoshiyuki Ueno Takeo Kato Takamasa Kayama Isao Kubota 《International journal of medical sciences》2013,10(11):1530-1536
Background:Plasma fibrinogen is considered a biomarker of respiratory disease, owing to the relationship between plasma fibrinogen and pulmonary function established in Western populations. However, such a relationship has not yet been confirmed in an Asian population. We assessed this relationship in the general Japanese population.Methods:Totally, 3,257 men and women aged ≥40 years who participated in a community-based annual health checkup in Takahata, Japan, from 2004 to 2006, underwent spirometry, and their plasma fibrinogen levels were determined.Results:We found an inverse relationship between spirometric measures (percent predicted forced vital capacity [%FVC] and forced expiratory volume in 1s [%FEV1], and FEV1/FVC) and plasma fibrinogen levels in men, but not in women. The plasma fibrinogen levels were significantly higher in subjects with restrictive, obstructive, and mixed ventilatory disorders than in those with normal spirometry results. Multiple linear regression analysis revealed that in men, plasma fibrinogen levels were predictive for %FVC and %FEV1 (independent of age, body mass index, and cigarette smoking) but not for FEV1/FVC.Conclusions:Plasma fibrinogen was significantly associated with pulmonary function in Japanese men, and as such, plasma fibrinogen might be a potent biomarker for pulmonary dysfunction in men. 相似文献
135.
136.
HMG-CoA reductase inhibitors promote cholesterol-dependent Akt/PKB translocation to membrane domains in endothelial cells 总被引:5,自引:0,他引:5
Skaletz-Rorowski A Lutchman M Kureishi Y Lefer DJ Faust JR Walsh K 《Cardiovascular research》2003,57(1):253-264
OBJECTIVE: Recent results have shown that 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors referred to as statins rapidly activate the protein kinase Akt/PKB in endothelial cells (ECs) and endothelial precursor cells (EPCs). This pathway is critical for cellular responses that contribute to angiogenesis and EC function including nitric oxide production, cellular survival and migration. METHODS: Here we tested whether statins control the translocation of recombinant and endogenous Akt to the plasma membrane of endothelial cells in a cholesterol-dependent manner. RESULTS: Low doses of statins rapidly induce the translocation of Akt to discrete sites in endothelial cell plasma membrane that colocalize with F-actin-positive, focal adhesion kinase (FAK)-negative lamellipodia and filopodia. This translocation event requires the lipid-binding, pleckstrin homology domain of Akt. Treatment with phosphoinositide 3-kinase (PI 3-kinase) inhibitors or the HMG-CoA reductase reaction product L-mevalonate blocks the translocation of Akt in response to statin stimulation. Furthermore, the ability of statins to promote Akt activation and translocation to the membrane is inhibited by cholesterol delivery to cells, but cholesterol loading had no effect on VEGF-induced Akt activation. CONCLUSIONS: These results suggest that statin activation of Akt signaling is mediated by the translocation of Akt to cholesterol-sensitive membrane structures within activated ECs. 相似文献
137.
Cold pain prolongs gastric emptying of liquid but not solid meal: an electrical impedance tomography (EIT) study 总被引:2,自引:0,他引:2
Nakae Y Kagaya M Takagi R Matsutani Y Horibe H Kondo T 《Journal of gastroenterology》2000,35(8):593-597
Stressful stimuli are reported to affect gastric emptying. However, methods for measuring gastric emptying are, in themselves,
stressful. Electrical impedance tomography (EIT) is a method for measuring gastric emptying noninvasively. We used EIT to
measure gastric emptying of liquid and solid meals to determine the effect of cold pain stress on gastric emptying. EIT (DAS-01P
APT system; University of Sheffield, UK) was carried out in six healthy women (age, 21.6 ± 0.4 [mean ± SD] years) who had
ingested a liquid (potage, 263 g; 139 kcal) or solid (beef patty, 205 g; 435 kcal) test meal. Cold pain stimuli consisted
of repeated immersions of the subject's non-dominant hand into ice water (4°C) for 1 min, with a 15-s recovery period between
immersions, for a total of 20 min. For the control stimulus, water at 37°C was used. The cold pain stimulus was applied immediately
after the ingestion of a test meal. All studies were carried out randomly in each subject at intervals of more than 1 week.
With cold pain, the half emptying time of the liquid meal was significantly greater than that with the control stimulus (47.6
± 26.1 min vs 28.1 ± 10.8 min, P < 0.05). For the solid meal, the half emptying time did not differ between stimuli (101.9 ± 44.8 min with cold pain vs 92.6
± 30.5 min with control stimulus). There were no significant differences in lag time between the liquid and solid meals. Cold
pain stress delayed gastric emptying of liquid but not solid meals.
Received: September 28, 1999 / Accepted: February 25, 2000 相似文献
138.
Bax interacts with the permeability transition pore to induce permeability transition and cytochrome c release in isolated mitochondria 总被引:20,自引:0,他引:20
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Masashi Narita Shigeomi Shimizu Toshinori Ito Thomas Chittenden Robert J. Lutz Hikaru Matsuda Yoshihide Tsujimoto 《Proceedings of the National Academy of Sciences of the United States of America》1998,95(25):14681-14686
Cytochrome c release and the mitochondrial permeability transition (PT), including loss of the transmembrane potential (Δψ), play an important role in apoptosis. Using isolated mitochondria, we found that recombinant Bax and Bak, proapoptotic members of the Bcl-2 family, induced mitochondrial Δψ loss, swelling, and cytochrome c release. All of these changes were dependent on Ca2+ and were prevented by cyclosporin A (CsA) and bongkrekic acid, both of which close the PT pores (megachannels), indicating that Bax- and Bak-induced mitochondrial changes were mediated through the opening of these pores. Bax-induced mitochondrial changes were inhibited by recombinant Bcl-xL and transgene-derived Bcl-2, antiapoptotic members of the Bcl-2 family, as well as by oligomycin, suggesting a possible regulatory effect of F0F1-ATPase on Bax-induced mitochondrial changes. Proapoptotic Bax- and Bak-BH3 (Bcl-2 homology) peptides, but not a mutant BH3 peptide nor a mutant Bak lacking BH3, induced the mitochondrial changes, indicating an essential role of the BH3 region. A coimmunoprecipitation study revealed that Bax and Bak interacted with the voltage-dependent anion channel, which is a component of PT pores. Taken together, these findings suggest that proapoptotic Bcl-2 family proteins, including Bax and Bak, induce the mitochondrial PT and cytochrome c release by interacting with the PT pores. 相似文献
139.
Line Lykke Andersen Nanna M?rk Line S. Reinert Emil Kofod-Olsen Ryo Narita Sofie E. J?rgensen Kristian A. Skipper Klara H?ning Hans Henrik Gad Lars ?stergaard Torben F. ?rntoft Veit Hornung S?ren R. Paludan Jacob Giehm Mikkelsen Takashi Fujita Mette Christiansen Rune Hartmann Trine H. Mogensen 《The Journal of experimental medicine》2015,212(9):1371-1379
140.