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41.
Two years of prospective data on 416 back injuries were gatheredat a 1100-bed acute and tertiary care hospital to assist targetprevention efforts. The rate of injury among 1645 nurses wasfound to be highest for those working on orthopaedic, medicine,neurology, spinal and surgery wards, indicating priorities forprevention. In fact, 51% of the orthopaedic nurses sustained at least oneback injury during the two-year period. Gender did not significantlyaffect the risk for back injury; however, injuries were slightlymore common in nurses with less seniority and younger nurseswere found to be at significantly increased risk of back injury.Almost 63% of the back injuries which occurred in nurses working8 h shifts on the high-risk wards occurred during the firsttwo hours of the shift. Lifting and transferring patients withassistance were the two most common mechanisms for back injury(22.6% and 23.3%, respectively). In total, injured nurses attributed52.3% of their injuries to inadequate training; inadequate staffingwas given as the primary reason for 13.8% of the injuries. Theresults suggest that training in the indications for and useof mechanical devices for lifting/transferring patients requiresintensification, and a ‘warm-up’ period should alsobe considered in the face of injuries occurring early in theshift if work activities cannot be evenly planned.  相似文献   
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This study uses the 1988 National Health Interview Survey (NHIS) data to examine the effects of both heavy and problem drinking as well as moderate or light parental alcohol use on children's behaviour problems. The analysis is formulated within Becker's household production function framework. The production of child behavioural health is estimated using items from the Behavior Problems Index, a battery of 32 questions about behaviour problems which is derived from the Child Behavior Checklist (CBCL), a widely-used parent report instrument. Measures of parents' alcohol consumption are constructed from the NHIS Alcohol Supplement that was administered to one randomly selected adult in each household in 1988. Ordinary least squares (OLS) and two-stage least squares (TSLS) results are presented. The results provide consistent evidence that parental alcohol use is an input with negative marginal product in the production of child behavioural health, regardless of which parent drinks. The magnitude of the effect is generally larger in the TSLS specification. There is also strong evidence of relationships between some family structure variables and child behavioural health and between parental physical health and child behavioural health.  相似文献   
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PURPOSE: We evaluated anthropometric and performance measures that best predict bone mineral density (BMD) and bone mineral content (BMC) in 54 adolescent girls (14.6 +/- 0.5 yr; 22.7 +/- 14.0 months past menarche). METHODS: Whole body, femoral neck, greater trochanter, lumbar spine (L2-L4), and mid-femoral shaft BMD and BMC, and whole body bone-free lean mass and fat mass were assessed using DXA (Hologic QDR 1000/W). Knee extensor strength and leg power were assessed by isokinetic dynamometry and the Wingate Anaerobic Power Test, respectively. RESULTS: Whole body lean mass was correlated with BMD at all bone sites (r = 0.45-0.77; P < 0.001) and was more highly correlated with bone at all sites than was body weight. Leg power was also associated with BMD at all sites (r = 0.41-0.67; P < 0.001), whereas leg strength correlated significantly with all sites (r = 0.41-0.53; P < 0.001) except the lumbar spine. Stepwise regression analyses revealed that 59% of the variance in whole body BMD was predicted by lean mass alone. No other variables, including fat mass, height, months past menarche, leg power, or leg strength, contributed additionally to the regression model. Similarly, lean mass was the only predictor of lumbar spine and femoral shaft BMD (R2 = 0.25, R2 = 0.37, respectively), while femoral neck and trochanteric BMD were best predicted by leg power (R2 = 0.38, R2 = 0.36, respectively). Similar but stronger models emerged using BMC as the outcome, with lean mass and leg power explaining the most variance in BMC values. CONCLUSION: In this group of adolescent girls, lean body mass and leg power best predicted BMC and BMD of the whole body, lumbar spine, femoral shaft, and hip, which may suggest an important role for muscle mass development during growth to maximize peak bone density.  相似文献   
44.
PURPOSE: Long-term outcomes of a minimally invasive method of correcting vesicoureteral reflux are presented with a discussion of the modification in our original technique. PATIENTS AND METHODS: A total of 29 children (46 refluxing ureters), 14 months to 18 years old, underwent percutaneous endoscopic trigonoplasty (PET) between December 1994 and June 1996. Follow-up ranged from 19 to 37 months. Reflux was grade 1 in 2, grade 2 in 16, grade 3 in 19, grade 4 in 8, and grade 5 in 1. The technique was a Gil-Vernet method in the first 23 patients and Cohen reimplantation in the last 6 patients. RESULTS: Resolution of reflux was observed to decrease from 63% to 47% with long-term (30-37 months') follow-up using the Gil-Vernet technique. Resolution was greater with unilateral reflux than bilateral reflux (83% v. 27%, respectively). The Cohen technique resulted in resolution of reflux in 83%; however, the operating time nearly doubled when compared with the Gil-Vernet group. In both groups, failure was unrelated to grade of reflux, age, operative sequence, or bladder instability. CONCLUSIONS: Although showing an improvement in resolution of reflux over the Gil-Vernet PET procedure, the Cohen PET reimplant has a lower success rate than traditional open operative reimplants. The PET also requires more operating time and two operating surgeons. Despite some advantages in the promptness of recovery, we do not recommend PET by either technique at this time. Future modifications may make this approach more tenable.  相似文献   
45.
Chondroitin sulfate proteoglycan (CSPG) inhibits outgrowth from embryonic chick and rodent neurons in vivo and in vitro and is upregulated during development and following injury. The role of CSPG in outgrowth from human neurons has been largely untested, but is critical for our understanding of regeneration in humans following nervous system injury. Here we determined the effects of CSPG on platelet-derived growth factor (PDGF)-stimulated neurite outgrowth from SH-SY5Y human neuroblastoma cells, a well-accepted model of neuronal differentiation. Cells were plated on glass coverslips adsorbed with laminin (LN), CSPG, or a patterned substratum consisting of alternating stripes of the two molecules. Similar to other studies using chick or rodent neurons, SH-SY5Y cells extend neurites on LN, displaying a 15.2% increase in the total neurite length/cell as compared to cells plated on glass. Cells plated on CSPG alone exhibited reduced neurite outgrowth compared to cells plated on glass or LN. Interestingly, SH-SY5Y growth cones extending on LN and then encountering a CSPG border display more stopping/stalling (62.3%) than turning (27.9%) behaviors. Soluble CSPG inhibits neurite initiation from SH-SY5Y cells plated on glass, but not on LN. These data demonstrate that several CSPG-elicited responses of human neuron-like cells are similar to those from nonhuman neurons. However, approximately 70% of SH-SY5Y growth cones stop or stall at a CSPG border while over 80% of chick sensory neurons turn at a CSPG border. The experimental difference between these models may well indicate a functional difference between animal and human neuronal regeneration.  相似文献   
46.
We used Monte Carlo Markov chain (MCMC) methods to analyze a quantitative trait, MAO level, and a discrete trait, Collaborative Study on the Genetics of Alcoholism (COGA) alcoholism. Segregation, linkage, and haplotype sharing were analyzed and effects of marker map features were examined. For MAO, modest signals were found on chromosomes 1 and 17 for raw data, and 15 for covariate-adjusted data. For alcoholism, a strong signal was found on chromosome 1 with modest signals on chromosomes 4 and 10.  相似文献   
47.
Quantitative DNA analysis has often been proposed as a potential tool capable of detecting preneoplastic tissue and as such to function as an intermediate endpoint in cancer chemoprevention trials. The first aim of this study was to test whether cytomorphometric parameters could be used to detect field cancerization characteristics in cytological preparations of oral mucosa. Cytomorphometric parameters in exfoliated cells of apparently normal oral mucosa of head and neck cancer patients were compared with those of healthy controls. The second aim was to assess the value of these parameters subsequently as intermediate endpoint biomarkers in the mucosa of 70 patients receiving N-acetylcysteine and/or retinyl-palmitate as chemopreventive drugs. No differences were detected between 'high risk' and healthy mucosa, nor were differences observed before and after treatment.  相似文献   
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