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141.
Marco A. Mascarella Reza Forghani Salvatore Di Maio Denis Sirhan Anthony Zeitouni Gerard Mohr Marc A. Tewfik 《Skull base》2015,76(3):195-201
Objective To identify clinicopathologic factors associated with a reduced intercarotid distance (ICD) and subgroups at risk for internal carotid artery injury during transsphenoidal surgery.
Design A retrospective case-control study.
Setting This study was conducted at the McGill University Health Centre, a university-affiliated tertiary care center.
Participants Patients with a sellar or parasellar tumor and nontumor controls were included in the study.
Main Outcome Measures The smallest distance between the internal carotid arteries at the clival, cavernous, and paraclinoid segments on coronal magnetic resonance imaging was measured. Demographic profiles, cephalometric measurements, tumor dimensions, and sphenoid configuration were assessed as potential determinants of the ICD.
Results A total of 212 cases and 34 controls were analyzed. Widening of the ICD at the three segments of the internal carotid arteries was found in patients with pituitary macroadenomas (p < 0.01). Patients with a growth hormone–secreting adenoma had a markedly reduced ICD at the clivus compared with controls (1.59 cm versus 1.77 cm; p = 0.02; 95% confidence interval [CI], 0.03–0.32). The paraclinoid ICD was reduced in patients with an anterior fossa meningioma (1.24 cm versus 1.33 cm; p = 0.04; 95% CI, 0.01–0.45).
Conclusion Identifying clinicopathologic factors affecting the ICD can help surgeons recognize constraints to endoscopic access of the skull base and avoid inadvertent arterial injury. 相似文献
142.
143.
M. Riffelmann J. Mohr W. Hellenbrand C. H. Wirsing von Koenig 《European journal of clinical microbiology & infectious diseases》2014,33(5):805-808
We evaluated whether the results of diagnostic polymerase chain reaction (PCR) testing combined with time since last vaccine dose could be used to monitor the effectiveness of acellular pertussis vaccines. In 258 consecutive nasopharyngeal swabs from children and adolescents with typical pertussis symptoms, 80 were positive and 178 were negative in PCR for Bordetella pertussis DNA (IS 481). Time since last vaccine dose was available for 152 patients, of which 120 were fully immunised. Among the fully vaccinated patients, the median age of 41 PCR-positive patients was 8.4 years (range 0.9–12.3) and that of 79 PCR-negative cases was 3.3 years (range 0.4–14.1) (p?<?0.01). The median time since last pertussis vaccine dose was 6.05 years [95 % confidence interval (CI): 0.5–10.9] in PCR-positive cases and 2.22 years (95 % CI: 0.04–9.23) in PCR-negative cases (p?<?0.001). The use of diagnostic PCR results from pertussis cases together with time since last vaccine dose permits estimates of the duration of protection after vaccination with acellular pertussis vaccines that are in keeping with more complex studies. 相似文献
144.
Raphael Schween Wolfgang Taube Albert Gollhofer Christian Leukel 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2014,232(9):3007-3013
Multiple motor learning processes can be discriminated in visuomotor rotation paradigms. At least four processes have been proposed: Implicit adaptation updates an internal model based on prediction errors. Model-free reinforcement reinforces actions that achieve task success. Use-dependent learning favors repetition of prior movements, and strategic learning uses explicit knowledge about the task. The current experiment tested whether the processes involved in motor learning differ when visual feedback is altered. Specifically, we hypothesized that online and post-trial feedback would cause different amounts of implicit adaptation. Twenty subjects performed drawing movements to targets under a 45° counterclockwise visuomotor rotation while aiming at a clockwise adjacent target. Subjects received visual feedback via a cursor on a screen. One group saw the cursor throughout the movement (online feedback), while the other only saw the final position after movement execution (post-trial feedback). Both groups initially hit the target by applying the strategy. After 80 trials, subjects with online feedback had drifted in clockwise direction [mean direction error: 15.1° (SD 11.2°)], thus overcompensating the rotation. Subjects with post-trial feedback remained accurate [mean: 0.7° (SD 2.0°), TIME × GROUP: F = 3.926, p = 0.003]. We interpret this overcompensation to reflect implicit adaptation isolated from other mechanisms, because it is driven by prediction error rather than task success (model-free reinforcement) or repetition (use-dependent learning). The current findings extend previous work (e.g., Mazzoni and Krakauer in J Neurosci 26:3642–3645, 2006; Hinder et al. in Exp Brain Res 201:191–207, 2010) and suggest that online feedback promotes more implicit adaptation than does post-trial feedback. 相似文献
145.
The association between cardiovascular risk factors and high blood pressure in adolescents: A school‐based study 下载免费PDF全文
146.
Alexsandra R.m. Favacho Isabelle Roger Amanda K. Akemi Adonai A. Pessoa JR. Andrea G. Varon Raphael Gomes Daniela T. Godoy Sandro Pereira Elba R.s. Lemos 《Revista do Instituto de Medicina Tropical de S?o Paulo》2014,56(4):363-365
Bartonella henselae is associated with a wide spectrum of clinical
manifestations, including cat scratch disease, endocarditis and meningoencephalitis,
in immunocompetent and immunocompromised patients. We report the first molecularly
confirmed case of B. henselae infection in an AIDS patient in state
of Rio de Janeiro, Brazil. Although DNA sequence of B. henselae has
been detected by polymerase chain reaction in a lymph node biopsy, acute and
convalescent sera were nonreactive. 相似文献
147.
148.
E. D. Gorham C. F. Garland A. A. Burgi S. B. Mohr K. Zeng H. Hofflich J. J. Kim C. Ricordi 《Diabetologia》2012,55(12):3224-3227
Aims/hypothesis
Low serum 25-hydroxyvitamin D [25(OH)D] concentration may increase risk of insulin-requiring diabetes.Methods
A nested case–control study was performed using serum collected during 2002–2008 from military service members. One thousand subjects subsequently developed insulin-requiring diabetes. A healthy control was individually matched to each case on blood-draw date (±2?days), age (±3?months), length of service (±30?days) and sex. The median elapsed time between serum collection and first diagnosis of diabetes was 1?year (range 1?month to 10?years). Statistical analysis used matched pairs and conditional logistic regression.Results
ORs for insulin-requiring diabetes by quintile of serum 25(OH)D, from lowest to highest, were 3.5 (95% CI 2.0, 6.0), 2.5 (1.5, 4.2), 0.8 (0.4, 1.4), 1.1 (0.6, 2.8) and 1.0 (reference) (p trend <0.001). The quintiles (based on fifths using serum 25(OH)D concentration in the controls) of serum 25(OH)D in nmol/l, were <43 (median 28), 43–59 (median 52), 60–77 (median 70), 78–99 (median 88) and ≥100 (median 128).Conclusions/interpretation
Individuals with lower serum 25(OH)D concentrations had higher risk of insulin-requiring diabetes than those with higher concentrations. A 3.5-fold lower risk was associated with a serum 25(OH)D concentration ≥60?nmol/l. 相似文献149.
Patel PR Ramakrishnan SK Kaw MK Raphael CK Ghosh S Marino JS Heinrich G Lee SJ Bourey RE Hill JW Jung DY Morgan DA Kim JK Rahmouni K Rahmouni SK Najjar SM 《Diabetologia》2012,55(3):763-772
Aims/hypothesis
The carcino-embryonic antigen-related cell adhesion molecule (CEACAM)2 is produced in many feeding control centres in the brain, but not in peripheral insulin-targeted tissues. Global Ceacam2 null mutation causes insulin resistance and obesity resulting from hyperphagia and hypometabolism in female Ceacam2 homozygous null mutant mice (Cc2 [also known as Ceacam2]?/?) mice. Because male mice are not obese, the current study examined their metabolic phenotype.Methods
The phenotype of male Cc2 ?/? mice was characterised by body fat composition, indirect calorimetry, hyperinsulinaemic?Ceuglycaemic clamp analysis and direct recording of sympathetic nerve activity.Results
Despite hyperphagia, total fat mass was reduced, owing to the hypermetabolic state in male Cc2 ?/? mice. In contrast to females, male mice also exhibited insulin sensitivity with elevated ??-oxidation in skeletal muscle, which is likely to offset the effects of increased food intake. Males and females had increased brown adipogenesis. However, only males had increased activation of sympathetic tone regulation of adipose tissue and increased spontaneous activity. The mechanisms underlying sexual dimorphism in energy balance with the loss of Ceacam2 remain unknown.Conclusions/interpretation
These studies identified a novel role for CEACAM2 in the regulation of metabolic rate and insulin sensitivity via effects on brown adipogenesis, sympathetic nervous outflow to brown adipose tissue, spontaneous activity and energy expenditure in skeletal muscle. 相似文献150.