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101.
Hyperpolarizing and depolarizing actions of dopamine via D-1 and D-2 receptors on nucleus accumbens neurons 总被引:4,自引:0,他引:4
The effect of dopamine (DA) on the nucleus accumbens neurons in guinea-pig brain slices was studied by intracellular recordings. DA caused a hyperpolarization in 28% of the neurons tested, a depolarization in 11%, and a hyperpolarization followed by a depolarization in 53%. The remaining neurons were unaffected. Analyses of the responses revealed that the DA hyperpolarization was produced by activation of the D-1 receptor and associated with an increase in potassium conductance, whereas the DA depolarization was generated by activation of the D-2 receptor and accompanied by a decrease in potassium conductance. DA uptake inhibitors augmented both the hyperpolarizing and depolarizing responses, while cyclic adenosine monophosphate selectively enhanced the former. 相似文献
102.
103.
From 1972 to 1985, 40 cases of congenital dilatation of the bile duct (CDBD) were experienced in the department of the authors. Those consisted of 19 cases of anomalous arrangement of the pancreatico-bile duct (P-B anomaly), five of bile duct carcinoma, and two of gall bladder carcinoma. In addition, four patients who showed no dilatation of the bile duct in spite of the presence of a P-B anomaly were experienced, and coexistent gall bladder carcinoma was present in three of four cases. The incidence of bile duct carcinoma associated with CDBD is very high. However, coexistent gall bladder carcinoma in CDBD is a new topic, and coexistent intrahepatic bile duct carcinoma in CDBD is extremely rare. This report presents interesting and rare cases of coexistent carcinomas in these anomalies and investigates their carcinogenesis, particularly that of gall bladder carcinoma. 相似文献
104.
ROLE OF PULMONARY INNERVATION IN CANINE IN SITU LUNG-PERFUSION PREPARATION: A NEW MODEL OF NEUROGENIC PULMONARY OEDEMA 总被引:1,自引:0,他引:1
Jiro Nakamura Shiwei Zhang Naohisa Ishikawa 《Clinical and experimental pharmacology & physiology》1987,14(6):535-542
1. In situ canine lungs were perfused in the presence or absence of the nerves which coursed to the heart and lungs (the cardiopulmonary nerves, CPN). 2. A right heart-bypassed preparation was made first, so that the respiratory and circulatory conditions could be controlled beforehand. It was then switched to a lung-perfusion preparation, in which the lungs receive all influences of sudden cessation of the brain and systemic circulations solely via the CPN. Hydrostatic mechanisms causing pulmonary oedema were excluded by adjusting the pulmonary arterial pressure under 300 mmH2O (less than 24 mmHg). 3. Accumulation of extravascular lung water and the rate of reservoir blood loss were significantly lower in the CPN-severed group than in the CPN-intact group. 4. After perfusion of 90 min, total loss of reservoir blood was correlated significantly with extravascular water content in lungs. The former was larger than the latter. 5. Elevation of left atrial pressure caused an increase in the rate of reservoir blood loss. When the CPN was severed, the relation between these two parameters was shifted to the right. 6. These findings indicate a CPN-mediated genesis of permeability pulmonary oedema. 相似文献
105.
Intracellular recordings were made from rat nucleus accumbens neurons in a tissue slice in vitro; postsynaptic potentials (p.s.p.) were evoked by focal electrical stimulation of the slice surface. P.s.p. were partially blocked by bicuculline (30 microM), partially blocked by a combination of 6-cyano-2,3-dihydroxy-7-nitroquinoxaline (CNQX, 10 microM) and DL-2-amino-5-phosphonovaleric acid (APV, 30 microM) and completely blocked when all three antagonists were applied together. Both the gamma-aminobutyric acid (GABA)-mediated p.s.p. (in CNQX and APV) and the glutamate-mediated p.s.p. (in bicuculline) were inhibited by baclofen (10-300 microM), adenosine (10-300 microM) and N6-(2-phenylisopropyl)adenosine (0.1-3 microM). Theophylline competitively antagonized the action of adenosine with an apparent dissociation equilibrium constant of about 15 microM. Baclofen, adenosine and N6-(2-phenylisopropyl)adenosine caused small (less than 10 mV) hyperpolarizations; voltage clamp experiments indicated that this resulted from an outward potassium current. It is concluded that activation of GABAB receptors and adenosine A1 receptors inhibits the release of glutamate and GABA at synapses in the nucleus accumbens. 相似文献
106.
Morozumi M Hasegawa K Kobayashi R Inoue N Iwata S Kuroki H Kawamura N Nakayama E Tajima T Shimizu K Ubukata K 《Antimicrobial agents and chemotherapy》2005,49(6):2302-2306
A total of 195 Mycoplasma pneumoniae strains were isolated from 2,462 clinical specimens collected between April 2002 and March 2004 from pediatric outpatients with respiratory tract infections. Susceptibilities to six macrolide antibiotics (ML), telithromycin, minocycline, levofloxacin, and sitafloxacin were determined by the microdilution method using PPLO broth. A total of 183 M. pneumoniae isolates were susceptible to all agents and had excellent MIC90s in the following order: 0.00195 microg/ml for azithromycin and telithromycin, 0.0078 microg/ml for clarithromycin, 0.0156 microg/ml for erythromycin, 0.0625 microg/ml for sitafloxacin, 0.5 microg/ml for minocycline, and 1 microg/ml for levofloxacin. Notably, 12 ML-resistant M. pneumoniae strains were isolated from patients with pneumonia (10 strains) or acute bronchitis (2 strains). These strains showed resistance to ML with MICs of >or=1 microg/ml, except to rokitamycin. Transition mutations of A2063G or A2064G, which correspond to A2058 and A2059 in Escherichia coli, in domain V on the 23S rRNA gene in 11 ML-resistant strains were identified. By pulsed-field gel electrophoresis typing, these strains were classified into groups I and IIb [corrected] as described previously (A. Cousin-Allery, A. Charron, B. D. Barbeyrac, G. Fremy, J. S. Jensen, H. Renaudin, and C. Bebear, Epidemiol. Infect. 124:103-111, 2000). These findings suggest that excessive usage of MLs acts as a trigger to select mutations on the corresponding 23S rRNA gene with the resultant occurrence of ML-resistant M. pneumoniae. Monitoring ML susceptibilities for M. pneumoniae is necessary in the future. 相似文献
107.
The N-terminal domain of thrombomodulin sequesters high-mobility group-B1 protein, a novel antiinflammatory mechanism 总被引:12,自引:0,他引:12
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Abeyama K Stern DM Ito Y Kawahara K Yoshimoto Y Tanaka M Uchimura T Ida N Yamazaki Y Yamada S Yamamoto Y Yamamoto H Iino S Taniguchi N Maruyama I 《The Journal of clinical investigation》2005,115(5):1267-1274
Thrombomodulin (TM) is an endothelial anticoagulant cofactor that promotes thrombin-mediated formation of activated protein C (APC). We have found that the N-terminal lectin-like domain (D1) of TM has unique antiinflammatory properties. TM, via D1, binds high-mobility group-B1 DNA-binding protein (HMGB1), a factor closely associated with necrotic cell damage following its release from the nucleus, thereby preventing in vitro leukocyte activation, in vivo UV irradiation-induced cutaneous inflammation, and in vivo lipopolysaccharide-induced lethality. Our data also demonstrate antiinflammatory properties of a peptide spanning D1 of TM and suggest its therapeutic potential. These findings highlight a novel mechanism, i.e., sequestration of mediators, through which an endothelial cofactor, TM, suppresses inflammation quite distinctly from its anticoagulant cofactor activity, thereby preventing the interaction of these mediators with cell surface receptors on effector cells in the vasculature. 相似文献
108.
109.
M. Okazaki K. Suzuki N. Asano K. Araki N. Shukuya T. Egami Y. Higurashi K. Morita H. Uchimura T. Watanabe 《Journal of infection and chemotherapy》2002,8(1):37-42
We investigated the effectiveness of fosfomycin combined with other antibiotics, such as piperacillin, cefepime, ceftazidime,
imipenem, meropenem, aztreonam, gentamicin, or levofloxacin, against 30 Pseudomonas aeruginosa strains, including multidrug-resistant strains, isolated from clinical specimens, using the efficacy time index (ETI) assay.
The assay refers to the result of pharmacokinetics obtained from adult men volunteers, and yields an ETI to evaluate the effect
of a combination of antimicrobial agents. With the ETI, based on serum concentration 3 h after the administration of two antimicrobial
agents, the effectiveness of antimicrobial combinations was evaluated as follows: poor, ETI < 0.5; fair, 0.5 ≤ ETI < 1; good,
1 ≤ ETI < 8; and excellent, ETI ≥ 8. The combination of fosfomycin and cefepime (efficacy rate [excellent plus good], 76.7%)
and fosfomycin/aztreonam (efficacy rate, 76.7%) appeared to be the most effective, followed by fosfomycin/meropenem (efficacy
rate, 76.6%), fosfomycin/imipenem (efficacy rate, 73.3%), fosfomycin/ceftazidime (efficacy rate, 70%), fosfomycin/gentamicin
(efficacy rate, 70%), fosfomycin/piperacillin (efficacy rate, 66.7%), and fosfomycin/levofloxacin (efficacy rate, 66.7%).
Fosfomycin/cefepime, fosfomycin/aztreonam, and fosfomycin/meropenem may be clinically useful in selected patients, particularly
for P. aeruginosa. The ETI assay provided information on the minimum inhibitory concentration (MIC) of many pairs of combined antimicrobial
agents simultaneously. The ETI assay may be a useful technique with which to investigate the effect of combinations of antimicrobial
agents against P. aeruginosa, including multidrug-resistant strains.
Received: July 5, 2001 / Accepted: October 29, 2001 相似文献
110.
Takahasih S Nakajima M Kobayashi M Wakabayashi I Miyakoshi N Minagawa H Itoi E 《The Tohoku journal of experimental medicine》2002,198(4):207-214
Rotator cuff tendon cells (RCC) derived from surgical samples showed fibroblast-like morphology. Histological staining demonstrated collagen secretion by RCC. Immunohistological findings revealed that RCC secreted type I and III collagen, but not type II collagen. In addition, the SDS-PAGE analysis suggested that RCC predominantly produced type I collagen. Basic fibroblast growth factor (bFGF) had a stimulatory effect on the proliferation of RCC dose-dependently up to 1 ng/ml. Administration of bFGF suppressed the secretion of collagens from RCC in a dose-dependent manner. 相似文献