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91.
Susan Reisine Douglas E Morse Walter J Psoter Ellen Eisenberg Donald Cohen Deborah Cleveland Mirseyed Mohit-Tabatabai 《Journal of oral and maxillofacial surgery》2005,63(4):513-520
PURPOSE: We report findings from a study that measured associations between sociodemographic risk indicators and depressive symptoms among individuals diagnosed with either oral cancer or a premalignant lesion. MATERIALS AND METHODS: Incident cases of oral cancer and oral epithelial dysplasia (OED) were identified by reviewing pathology reports generated by 3 oral pathology laboratories serving primarily community-based oral and maxillofacial surgeons. Subjects were interviewed by telephone to collect information on sociodemographic characteristics, depressive symptoms using the Center for Epidemiologic Studies-Depression (CES-D) Scale, and social support using the Berkman Social Network Inventory. RESULTS: The analysis included 167 oral cancer and 234 OED cases. Nineteen percent of the subjects had a CES-D score indicative of clinical depression (CES-D > or =16). Forward and backward stepwise logistic regression identified diagnosis (cancer/OED), age, social support, employment status, and gender as sociodemographic indicators of CES-D scores of 16+. In the final model, which also controlled for smoking and drinking, the odds of having elevated CES-D scores (16+) were 79% higher among oral cancer relative to OED cases. The odds of high CES-D scores were significantly reduced in persons over the age of 50 compared with those aged 50 years and younger as well as in persons with higher, relative to low, levels of social support and in persons employed outside the home compared with those who were not. Although not statistically significant, men were more likely to have CES-D scores indicative of clinical depression. CONCLUSIONS: Knowledge of sociodemographic characteristics may assist the clinician in identifying those individuals with an elevated risk of concomitant depressive symptoms. 相似文献
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93.
Transport of an antifungal trypsin inhibitor isolated from corn across the blood-brain barrier 下载免费PDF全文
Banks WA Niehoff ML Brown RL Chen ZY Cleveland TE 《Antimicrobial agents and chemotherapy》2002,46(8):2633-2635
We determined whether an antifungal 14-kDa protein trypsin inhibitor isolated from corn is able to cross the blood-brain barrier. We found that it completely crossed the blood-brain barrier by means of a saturable mechanism at a rate of 0.153 microl/g. min, with about 0.082% of the intravenously injected dose being taken up per gram of brain. 相似文献
94.
A J DeLucca J M Bland T J Jacks C Grimm T E Cleveland T J Walsh 《Antimicrobial agents and chemotherapy》1997,41(2):481-483
Cecropin A (CA) fungicidal properties were explored. Nongerminated and germinated Aspergillus spp. and Fusarium spp. conidia were treated with CA. CA achieved complete lethality at < or = 25 microM (99 micrograms/ml) for germinating, but not nongerminating, conidia of Aspergillus spp. CA achieved total lethality for nongerminated and germinating conidia of Fusarium spp at 1.5 microM (6 micrograms/ml). MIC and minimal lethal concentration assays in buffered RPMI medium gave similar results. 相似文献
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96.
Shock wave therapy (SWT) refers to the use of focused shock waves for treatment of musculoskeletal indications including plantar fascitis and dystrophic mineralization of tendons and joint capsules. Measurements were made of a SWT device that uses a ballistic source. The ballistic source consists of a handpiece within which compressed air (1-4 bar) is used to fire a projectile that strikes a metal applicator placed on the skin. The projectile generates stress waves in the applicator that transmit as pressure waves into tissue. The acoustic fields from two applicators were measured: one applicator was 15 mm in diameter and the surface slightly convex and the second was 12 mm in diameter the surface was concave. Measurements were made in a water tank and both applicators generated a similar pressure pulse consisting of a rectangular positive phase (4 micros duration and up to 8 MPa peak pressure) followed by a predominantly negative tail (duration of 20 micros and peak negative pressure of -6 MPa), with many oscillations. The rise times of the waveforms were around 1 micros and were shown to be too long for the pulses to be considered shock waves. Measurements of the field indicated that region of high pressure was restricted to the near-field (20-40 mm) of the source and was consistent with the Rayleigh distance. The measured acoustic field did not display focusing supported by calculations, which demonstrated that the radius of curvature of the concave surface was too large to effect a focusing gain. Other SWT devices use electrohydraulic, electromagnetic and piezoelectric sources that do result in focused shock waves. This difference in the acoustic fields means there is potentially a significant mechanistic difference between a ballistic source and other SWT devices. 相似文献
97.
Nie LH Sanchez S Newton K Grodzins L Cleveland RO Weisskopf MG 《Physics in medicine and biology》2011,56(3):N39-N51
This study was conducted to investigate the methodology and feasibility of developing a portable x-ray fluorescence (XRF) technology to quantify lead (Pb) in bone in vivo. A portable XRF device was set up and optimal settings of voltage, current, and filter combination for bone lead quantification were selected to achieve the lowest detection limit. The minimum radiation dose delivered to the subject was calculated by Monte Carlo simulations. An ultrasound device was used to measure soft tissue thickness to account for signal attenuation, and an alternative method to obtain soft tissue thickness from the XRF spectrum was developed and shown to be equivalent to the ultrasound measurements (intraclass correlation coefficient, ICC = 0.82). We tested the correlation of in vivo bone lead concentrations between the standard KXRF technology and the portable XRF technology. There was a significant correlation between the bone lead concentrations obtained from the standard KXRF technology and those obtained from the portable XRF technology (ICC = 0.65). The detection limit for the portable XRF device was about 8.4 ppm with 2 mm soft tissue thickness. The entrance skin dose delivered to the human subject was about 13 mSv and the total body effective dose was about 1.5 μSv and should pose minimal radiation risk. In conclusion, portable XRF technology can be used for in vivo bone lead measurement with sensitivity comparable to the KXRF technology and good correlation with KXRF measurements. 相似文献
98.
Schweers RL Zhang J Randall MS Loyd MR Li W Dorsey FC Kundu M Opferman JT Cleveland JL Miller JL Ney PA 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(49):19500-19505
The regulated clearance of mitochondria is a well recognized but poorly understood aspect of cellular homeostasis, and defects in this process have been linked to aging, degenerative diseases, and cancer. Mitochondria are recycled through an autophagy-related process, and reticulocytes, which completely eliminate their mitochondria during maturation, provide a physiological model to study this phenomenon. Here, we show that mitochondrial clearance in reticulocytes requires the BCL2-related protein NIX (BNIP3L). Mitochondrial clearance does not require BAX, BAK, BCL-X(L), BIM, or PUMA, indicating that NIX does not function through established proapoptotic pathways. Similarly, NIX is not required for the induction of autophagy during terminal erythroid differentiation. NIX is required for the selective elimination of mitochondria, however, because mitochondrial clearance, in the absence of NIX, is arrested at the stage of mitochondrial incorporation into autophagosomes and autophagosome maturation. These results yield insight into the mechanism of mitochondrial clearance in higher eukaryotes. Furthermore, they show a BAX- and BAK-independent role for a BCL2-related protein in development. 相似文献
99.
Gruzman A Wood WL Alpert E Prasad MD Miller RG Rothstein JD Bowser R Hamilton R Wood TD Cleveland DW Lingappa VR Liu J 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(30):12524-12529
Amyotrophic lateral sclerosis (ALS) is a devastating motor neuron degenerative disease whose etiology and pathogenesis remain poorly understood. Most cases of ALS ( approximately 90%) are sporadic (SALS), occurring in the absence of genetic associations. Approximately 20% of familial ALS (FALS) cases are due to known mutations in the copper, zinc superoxide dismutase (SOD1) gene. Molecular evidence for a common pathogenesis of SALS and FALS has remained elusive. Here we use covalent chemical modification to reveal an attribute of spinal cord SOD1 common to both SOD1-linked FALS and SALS, but not present in normal or disease-affected tissues from other neurodegenerative diseases, including Alzheimer's, Parkinson's, and Huntington's diseases and spinal muscular atrophy, a non-ALS motor neuron disease. Biotinylation reveals a 32-kDa, covalently cross-linked SOD1-containing protein species produced not only in FALS caused by SOD1 mutation, but also in SALS. These studies use chemical modification as a novel tool for the detection of a disease-associated biomarker. Our results identify a shared molecular event involving a known target gene and suggest a common step in the pathogenesis between SALS and FALS. 相似文献
100.
Cleveland RH Zurakowski D Slattery DM Colin AA 《Proceedings of the American Thoracic Society》2007,4(4):302-305
We compare a chest radiographic scoring system developed by our group to spirometry in quantifying the longitudinal progression of lung disease among cystic fibrosis (CF) patients, and we evaluate the use of this radiographic scoring system in identifying the treatment effect of an inhaled antibiotic. Results suggest that longitudinally acquired chest radiographs, when scored using our scoring system, are at least as sensitive as lung function in detecting the progression of lung disease in CF patients. 相似文献