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1.
Nerve growth factor (NGF) and NGF receptors were measured in cortex and hippocampus of rats treated with drugs affecting cholinergic neurotransmission. High (Kd= 0.045nM) and low (Kd= 21nM) affinity125I-NGF binding sites were present in both cortical and hippocampal membranes with hippocampus containing higher numbers of both sites than cortex. Chronic treatment of rats with the muscarinic receptor antagonist scopolamine (5 mg/kg, twice daily) decreased the density of high- and low-affinity sites by 50–90% in cortical and hippocampal membranes. These changes were seen after 7 days, but not 3 days, of scopolamine treatment. Chronic infusion of physostigmine (1 mg/kg/day) using minipumps increased the number of high- and low-affinity sites in cortex 3- and 6-fold, respectively. The changes in receptor-binding parameters induced by physostigmine were transient as they were evident after 3 days of treatment, but returned to control levels after 7 days. NGF content in cortex and hippocampus was reduced by about 50% following 7, but not 3, days of chronic physostigmine infusion. In contrast, scopolamine treatment failed to change NGF levels in the cholinergic neuronal target regions but it decreased NGF content in the septal area. The content of NGF mRNA in the cortex measured by Northern blot analysis failed to change following either scopolamine or physostigmine treatment. The results suggest that levels of NGF and NGF receptors in the target regions of cholinergic neurons are regulated by the extent of cholinergic neurotransmitter activity. 相似文献
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G. Bradley Schaefer James N. Thompson John B. Bodensteiner James M. McConnell William J. Kimberling Charles T. Gay William D. Dutton David C. Hutchings Stanton B. Gray 《Annals of neurology》1996,39(3):382-385
There are conflicting reports on the relationship between cerebellar vermal lobule hypoplasia and autism. Using quantitative magnetic resonance image analysis, we measured the cerebellar vermis in 125 normal individuals with a broad age range and 102 patients with a variety of neurogenetic abnormalities. We conclude that hypoplasia of cerebellar vermal lobules VI and VII is a nonspecific finding that even occurs in several conditions without autistic behavior. This suggests that it is not a specific neuroanatomical marker for autism, nor is cerebellar dys- genesis likely to be solely responsible for clinical autistic behaviors. 相似文献
6.
Many public and private sector efforts are devoted toward increasing the training of physicians from under-represented minority groups, yet little has been documented regarding the association between physicians' racial backgrounds and the patient populations they serve. To address this question, we use 1987 National Medical Expenditure Survey to examine the impact of race/ethnicity on the matching between physician and patients. Our results show that minority patients are significantly more likely to report having a minority physician as their regular doctor. We estimate that minority patients are five times as likely as non-minorities to report that their regular physician is a member of a racial/ethnic minority. This effect is especially pronounced among Hispanics who identify a Hispanic physician as their regular provider 19 times more often than non-minorities. After controlling for other socio-economic factors, both these figures remain significant, but drop by approximately one-half. These results support the notion that minority patients tend to see minority physicians at a disproportional rate independent of other socio-economic factors. 相似文献
7.
Preventive care for patients following myocardial infarction. The Wessex Research Network (WReN) 总被引:2,自引:1,他引:1
OBJECTIVE: We aimed to assess general practice care for patients following
a myocardial infarction (MI). METHOD: A structured review was carried out
of general practice records of patients identified from hospital
administration data. A total of 266 survivors following MI were identified
from the discharge data of 13 hospitals in Southern England and registered
with 71 GPs belonging to the Wessex Research Network. Median time since
hospital discharge was 2.1 years. The main outcome measures were the
provision of appropriate preventive care, including cardiac rehabilitation,
drug therapy, and lifestyle advice for modifiable risk factors. RESULTS:
Basic care was provided to nearly all patients; 253 (95.1%, 95% Cl
91.8-97.4) had blood pressure documented after their MI, 216 of 234
patients eligible for aspirin (92.3%; 88.1-95.4) had been recommended
treatment, and the provision of advice on smoking cessation was documented
for 27 of 33 continuing smokers (81.8%; 64.5-93.0). However, only 73 of 236
patients eligible to attend a structured rehabilitation programme (30.9%;
25.0-36.8) were documented as having received rehabilitation. Of 89
patients with heart failure following MI, 33 (37.1%; 27.1-48.0) had no
record of having been offered treatment with an ACE inhibitor. Total
cholesterol measurement was documented for only 144 patients (54.1%;
48.1-60.1). We estimate that there is still the potential to prevent
between 4 and 9 deaths in this group of 266 surviving patients in the next
2 years by further improving the quality of follow-up care. CONCLUSIONS:
Preventive care in patients with proven ischaemic heart disease in general
practice remains haphazard, even among doctors enthusiastic to participate
in research and to audit their quality of care. As general practitioners we
should ensure that we are providing high quality preventive care to
patients with clinical disease before we focus on the even more demanding
task of primary prevention.
相似文献
8.
Dr. Sandra S. Garner Pharm.D. Dr. Donald B. Wiest Pharm.D. Mr. J. Warren Bradley R.R.T. 《Pharmacotherapy》1994,14(2):210-214
Study Objective . To determine albuterol delivery by metered-dose inhaler (MDI) in an in vitro pediatric mechanical ventilatory circuit model. The influence of a spacing device, endotracheal tube (ETT) diameter and length, and air humidity was also investigated. Design . An albuterol MDI canister was connected to an AeroVent spacer or Airlife MDI adapter and ETT 4.0, 5.0, or 6.0 mm at commercially available and equal lengths. The ETT tip was attached to an in-line filter holder with a 1-μm type A/E glass fiber filter. Ventilator settings were fractional concentration of inspired oxygen 50%, tidal volume 250 ml, inspiratory:expiratory (I:E) ratio 1:3, rate 25 breaths/minute, temperature 35°C, and a decelerating flow pattern. Ten albuterol canisters were activated two times each (total 2000 μg) into dry (4.0-, 5.0-, and 6.0-mm ETT) and humidified air (4.0- and 6.0-mm ETT) and repeated in triplicate. Percentage MDI output was determined by weighing the filter before and after drug administration (balance sensitivity 10 μg). Significant differences (p≤0.05) among the groups with and without a spacer and in dry and humidified air were determined by ANOVA with Scheffe's multiple comparison test. Multiple regression was used to determine significant associations between ETT diameter and length and delivery. Main Results . With the AeroVent spacer in humidified air, delivery with the 4.0- and 6.0-mm ETT was approximately 2.3% and 5%, respectively. The spacer and dry air significantly improved delivery. Conclusions . In humidified air, the dose of albuterol by MDI with an AeroVent spacer should be doubled for children intubated with 6.0-mm ETT, and four puffs administered for every one puff desired for 4.0-mm ETT. The results of this investigation should prove useful in initial clinical trials of albuterol MDI in ventilator-dependent infants and children. 相似文献
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