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71.
72.
AndrewJ. Stott Michel C. Maillard Vahri Beaumont David Allcock Omar Aziz Alexander H. Borchers Wesley Blackaby Perla Breccia Gillian Creighton-Gutteridge Alan F. Haughan Rebecca E. Jarvis Christopher A. Luckhurst Kim L. Matthews George McAllister Scott Pollack Elizabeth Saville-Stones Amanda J. Van de Poël Huw D. Vater Julie Vann Rachel Williams Dawn Yates Ignacio Muoz-Sanjun Celia Dominguez 《ACS medicinal chemistry letters》2021,12(3):380
Using an iterative structure–activity relationship driven approach, we identified a CNS-penetrant 5-(trifluoromethyl)-1,2,4-oxadiazole (TFMO, 12) with a pharmacokinetic profile suitable for probing class IIa histone deacetylase (HDAC) inhibition in vivo. Given the lack of understanding of endogenous class IIa HDAC substrates, we developed a surrogate readout to measure compound effects in vivo, by exploiting the >100-fold selectivity compound 12 exhibits over class I/IIb HDACs. We achieved adequate brain exposure with compound 12 in mice to estimate a class I/IIb deacetylation EC50, using class I substrate H4K12 acetylation and global acetylation levels as a pharmacodynamic readout. We observed excellent correlation between the compound 12 in vivo pharmacodynamic response and in vitro class I/IIb cellular activity. Applying the same relationship to class IIa HDAC inhibition, we estimated the compound 12 dose required to inhibit class IIa HDAC activity, for use in preclinical models of Huntington’s disease. 相似文献
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Chinn S Jarvis D Melotti R Luczynska C Ackermann-Liebrich U Antó JM Cerveri I de Marco R Gislason T Heinrich J Janson C Künzli N Leynaert B Neukirch F Schouten J Sunyer J Svanes C Vermeire P Wjst M Burney P 《Lancet》2005,365(9471):1629-35; discussion 1600-1
76.
Karolina Sikorska Nahid Mostafavi Montazeri André Uitterlinden Fernando Rivadeneira Paul HC Eilers Emmanuel Lesaffre 《European journal of human genetics : EJHG》2015,23(10):1384-1391
Analysis of genome-wide association studies with longitudinal data using standard procedures, such as linear mixed model (LMM) fitting, leads to discouragingly long computation times. There is a need to speed up the computations significantly. In our previous work (Sikorska et al: Fast linear mixed model computations for genome-wide association studies with longitudinal data. Stat Med 2012; 32.1: 165–180), we proposed the conditional two-step (CTS) approach as a fast method providing an approximation to the P-value for the longitudinal single-nucleotide polymorphism (SNP) effect. In the first step a reduced conditional LMM is fit, omitting all the SNP terms. In the second step, the estimated random slopes are regressed on SNPs. The CTS has been applied to the bone mineral density data from the Rotterdam Study and proved to work very well even in unbalanced situations. In another article (Sikorska et al: GWAS on your notebook: fast semi-parallel linear and logistic regression for genome-wide association studies. BMC Bioinformatics 2013; 14: 166), we suggested semi-parallel computations, greatly speeding up fitting many linear regressions. Combining CTS with fast linear regression reduces the computation time from several weeks to a few minutes on a single computer. Here, we explore further the properties of the CTS both analytically and by simulations. We investigate the performance of our proposal in comparison with a related but different approach, the two-step procedure. It is analytically shown that for the balanced case, under mild assumptions, the P-value provided by the CTS is the same as from the LMM. For unbalanced data and in realistic situations, simulations show that the CTS method does not inflate the type I error rate and implies only a minimal loss of power. 相似文献
77.
Clonal dysregulation of the antibody response to tetanus-toxoid after bone marrow transplantation 总被引:2,自引:0,他引:2
Gerritsen EJ; Van Tol MJ; Van 't Veer MB; Wels JM; Khouw IM; Touw CR; Jol-Van Der Zijde CM; Hermans J; Rumke HC; Radl J 《Blood》1994,84(12):4374-4382
After bone marrow transplantation (BMT), a prolonged dysregulation of humoral immunity can be observed. In the present study, we investigated whether this is reflected in an abnormal production of specific antibodies (Ab) to the T-cell-dependent recall antigen tetanus-toxoid (TT). The study group consisted of children receiving transplants of an unmodified allogeneic graft and of adults receiving either a T-cell- depleted allogeneic or an unmodified autologous BM graft. Findings were compared with those in healthy controls. In pediatric graft recipients, who were routinely revaccinated early after BMT, the Ab response was quantitatively superior to that in adult graft recipients who did not receive early revaccination. In the majority of graft recipients, the time period after vaccination required to reach the peak level of antibodies was prolonged and the number of responding TT-specific B- cell clones was markedly decreased in comparison with controls. In controls, a low frequency of dominant B-cell clones may produce low quantities of homogeneous Ab components (H-Ab) against a heterogeneous background. However, in BM graft recipients, "overshooting" of Ab production by separate B-cell clones was observed, resulting in the development of H-Ab at a relatively high concentration. These abnormalities were present up to 10 years after BMT, irrespective of either the age of the recipient, the modulation of the graft, or the vaccination schedule used. It is hypothesized that the dysregulated Ab production is the consequence of activation of a restricted number of resting memory B cells, present in germinal centers, repopulating gradually after BMT. Our data show that routine revaccination early after BMT improves the humoral immune response. However, because of a clonally dysregulated Ab production, long-lasting qualitative defects may be present even after normalization of Ab titers. 相似文献
78.
Robert Wilson Emily Jarvis Mickael Montembault J. Nicole Hamblin Edith M. Hessel Anthony Cahn 《Clinical therapeutics》2018,40(8):1410-1417
Purpose
Novel therapies to treat chronic obstructive pulmonary disease are highly desirable. The safety, tolerability, and pharmacokinetic (PK) parameters of nemiralisib, a phosphoinositide 3-kinase δ inhibitor, administered via the Ellipta dry powder inhaler (GlaxoSmithKline, Research Triangle Park, North Carolina) was evaluated, including an assessment of oral bioavailability.Methods
This single-center, 3-part, placebo-controlled trial in 22 healthy subjects evaluated single (100 and 200 μg) and repeat (200 μg for 10 days) doses of inhaled nemiralisib in parts A (n?=?12) and B (n?=?12) (double-blind) and single doses of inhaled nemiralisib (200 µg) with and without charcoal block in Part C (n?=?6) (open-label, 2-period, crossover). There was a minimum 14-day washout period between dosing days.Findings
21 subjects completed the study, mean age was similar in the three parts (A: 49 years; B: 44 years; C: 55 years). After single doses of nemiralisib, observed plasma Cmax dropped rapidly, followed by a slower elimination phase. Near-dose proportionality was observed: mean (95% CI) plasma Cmax and AUC0–24 values were 174.3 pg/mL (96.9–313.3) and 694.6 pg·h/mL (503.5–958.2) for 100 μg and 398.9 pg/mL (318.3–500.1) and 1699.6 pg·h/mL (1273.3–2268.7) for 200 μg, respectively. Repeat dosing for 10 days showed exposures ~2- to 4-fold higher than on the single dose (peak, trough, and AUC0–24 levels), achieving steady-state by day 6. Mean AUC0–24 was 2193.6 pg·h/mL and 1645.3 pg·h/mL in the absence/presence of charcoal. Two non–drug-related adverse events were observed; neither was serious or resulted in withdrawal.Implications
Inhalation of nemiralisib was well tolerated in these healthy subjects. Plasma pharmacokinetic variables were well defined, and charcoal block data indicate that ~23% of the total systemic exposure after inhalation from Ellipta was attributable to orally absorbed drug. ClinicalTrials.gov identifier: NCT02691325. 相似文献79.
Li XC Jarvis ED Alvarez-Borda B Lim DA Nottebohm F 《Proceedings of the National Academy of Sciences of the United States of America》2000,97(15):8584-8589
The high vocal center (HVC) controls song production in songbirds and sends a projection to the robust nucleus of the archistriatum (RA) of the descending vocal pathway. HVC receives new neurons in adulthood. Most of the new neurons project to RA and replace other neurons of the same kind. We show here that singing enhances mRNA and protein expression of brain-derived neurotrophic factor (BDNF) in the HVC of adult male canaries, Serinus canaria. The increased BDNF expression is proportional to the number of songs produced per unit time. Singing-induced BDNF expression in HVC occurs mainly in the RA-projecting neurons. Neuronal survival was compared among birds that did or did not sing during days 31-38 after BrdUrd injection. Survival of new HVC neurons is greater in the singing birds than in the nonsinging birds. A positive causal link between pathway use, neurotrophin expression, and new neuron survival may be common among systems that recruit new neurons in adulthood. 相似文献
80.
Continuous monitoring of mixed venous oxygen saturation as an indicator of pharmacologic intervention 总被引:1,自引:0,他引:1
This prospective study evaluated the ability of continuous SvO2 measurements to predict the onset and duration of action of the oral vasodilator, fenoldopam. Eight patients with New York Heart Association functional class 3 CHF received 100 mg fenoldopam in the fasted state. Serial hemodynamic parameters and SvO2 measurements were obtained at baseline and up to eight hours postdose. Although wide interpatient variability was observed, the SvO2-time response curve produced a similar trend as the CI-time response curve. The SvO2 may be a useful drug monitoring parameter in patients with NYHA class 3 CHF. Seriously ill patients may not have a good CI/SvO2 correlation. This is most likely due to an unstable oxygen consumption rate at the tissue level. Therefore, we recommend establishing the relationship between CI and SvO2 prior to its use as a drug monitoring parameter. 相似文献