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11.
ObjectiveTo test the validity of parent-reported birth information obtained through an online, self-administered questionnaire.MethodThe SENDO project is a prospective and dynamic paediatric cohort of Spanish children aged 4 to 6 years old at recruitment. Objective data from medical birth records were compared to parent-reported data getting intra-class correlation coefficients (ICC) for quantitative variables and weighted Kappa Index for qualitative ones. Percentage of responders and of total agreement was also evaluated.ResultsParental response rate was over 99% for birth weight and gestational age and 76% for birth length. ICC for birth weight was 0.95 (95% confidence interval [95%CI]: 0.94-0.96) and 0.78 (95%CI: 0.73-0.83) for birth length, both showing very high correlations. The total agreement percentage for gestational age was 97%, and Kappa weighted index was 0.90 (95%CI: 0.89-0.90), showing a very high agreement as well.ConclusionsWe found high correlations and excellent agreement in parent-reported birth data 4 to 6 years after delivery. Our results show parent-reported birth data, especially birth weight, are valid for use in epidemiological research.  相似文献   
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The underlying factor structure of a subset of 12 items, which comprise the psychosocial subscales of the EORTC QLQ-C30 was explored in a group of women, all with metastatic breast cancer who were participating in a psychosocial intervention study. Two main factors were identified in this exploratory factor analysis, representing emotional distress and functional ability dimensions. A preliminary assessment of the external validity of the two factor structure was undertaken. The results support the validity of a summative emotional distress and functional ability score in this sample of patients. The functional ability score discriminated well for subgroups defined by clinical status indicators (e.g., performance status, pain, chemotherapy treatment, fatigue). The emotional distress subscale discriminated with respect to suffering, fatigue and sleep disturbance. Both subscales converged with related concepts measured by independent instruments, providing support for convergent validity. Summative index scores may be advantageous for application in particular research situations; applying quality adjustments in health policy analyses; for screening purposes; to monitor populations and make comparisons across broad groups and as stratification variables in clinical trials. Further research to confirm the 2 factor structure is required in other samples before the interpretation can be accepted with confidence.  相似文献   
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目的 对美国CMS公司生产的肿瘤治疗计划系统 (TPS)计算结果值与实际测量值进行比较。方法 按照测量条件下的带有Farmer型电离室的固体水模在螺旋CT下进行扫描 ,图像通过网络数字传输系统传入TPS中 ,分别进行 10cm× 10cm规则野与不规则野、均匀组织与不均匀组织(分别含骨和肺 )、源轴距 10 0cm中心轴上深度 6和 10cm、野内任意点、机架角 30°、楔形板、MLC、铅挡、源皮距 90和 12 0cm条件下 6和 15MVX线计划设计并采用卷积和叠加两种算法计算 ,再与加速器治疗机上实际测量结果进行比较。结果 对于均匀组织和含骨的不均匀组织卷积和叠加算法的计算结果值具有良好的一致性 ,两种计算方法的结果偏差在 0 .5 %以内。多数实测值与计算值偏差在2 .5 %以内 ,个别计算与实测结果偏差在 3%以内 ,含肺的不均匀组织做不均匀组织校准后卷积算法与实测偏差较大 ,6MVX线为 7.8% ,15MVX线为 4 .5 % ,而叠加算法与实测偏差在 1.5 %以内。结论 除了卷积算法不能用于含肺组织或含气空腔剂量计算以外 ,卷积和叠加算法均可用于剂量计算 ,且偏差符合临床要求。  相似文献   
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OBJECTIVE: To construct and validate a computer instrument that identifies asthma patients receiving--theoretically--suboptimal drug therapy in community pharmacies, by the use of patient medication records. This selection enables the pharmacist to assist these patients in using medicines appropriately. METHODS: According to Dutch asthma guidelines which describe a stepwise approach and in order to define correct profiles for the use at each level of these guidelines, the optimum use of drugs in the different levels in asthma treatment was expressed in defined daily doses (DDDs) per pharmacological drug-group during a period of one year. An algorithmic computer instrument was developed to select patients with medication use deviant from these profiles. By using nine different selection profiles, the computer instrument stratified patients according to the medication records filed in the pharmacy computer. Patient medication records in four community pharmacies were investigated to validate the selection profiles as indicators for theoretically suboptimal drug use by asthma patients. The validation was performed by comparing the professional judgement of participating pharmacists with the selections made by the computer. MAIN OUTCOME MEASURE: Positive predictive value and negative predictive value of the selection made by algorithmic computer instrument. Rate of false-positive results. RESULTS: The computer instrument identified asthma patients using theoretically suboptimal drug therapy with approximately 95% predictive value compared with the professional judgement of the pharmacists. The rate of false-positive results was 5%. CONCLUSION: The results of the algorithmic computer instrument and the professional judgement of the pharmacists are in close agreement. The instrument will be utilised in further research in the IPMP study (Interventions on the principle of Pulmonary Medication Profiles) investigating the role of Dutch community pharmacists in counselling patients who are at risk of suboptimal drug use in the treatment of their asthma.  相似文献   
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The challenges faced on pesticide extraction from biological samples are finding a method that allows a multi-residue extraction, pre-concentration, clean-up, and isolation of analytes in just one step. In this sense, the hollow fiber – liquid phase microextraction method (HF- LPME) in the "solvent bar" mode was used to optimize and validate a method for pesticide multi-residue analysis in blood plasma at trace levels, through gas chromatography coupled with a flame ionization detector (GC-FID). Hollow fiber solvent bar microextraction HF-SBME was carried out with octanol immobilized into the pores of hydrophobic polypropylene fiber and disposed within a matrix of blood plasma, spiked with a mixture of pesticides (monocrotophos, lindane, aldrin, methyl parathion, endosulfan, dieldrin, DDD, DDT, and endrin). The optimization parameters evaluated were: extraction temperature and time, stirring speed, and salt concentration. A principal component analysis was performed to visualize the analytes' behaviour based on their explained variance, and then, a Box-Behnken analysis was generated to identify the optimum parameters. According to the PCA, all pesticides showed similar responses to the extraction method and the response of dieldrin exhibit the lowest variance. Moreover, the stationary points selected from the Box-Behnken analysis were 25.5 °C for the extraction temperature, 870 rpm for stirring speed, 16 min for extraction time, and 8.3 % w/v of salt concentration. Moreover, the validation results proved that HF-SBME is an alternative technique for pesticide multi-residue extraction in blood plasma. The analytes were able to concentrate, reaching 46 fold enrichment. The solvent type, sample and solvent volume were narrowed down without changing the method's precision or accuracy. The relative standard deviation was under 10 %, and the recovery was between 55 % and 105 % for the different analytes excepting lindane, which had lower recovery (27 %). The detection limits were 0.02 until 0.13 μg mL−1 for most of the pesticides used. Finally, HF-SBME is a good alternative for pesticide multi-residue extraction in complex matrices like plasma.  相似文献   
18.
The present study was conducted to evaluate the validity of the Food Frequency Questionnaire (FFQ) used in the RPS Birth Cohort Consortium (Ribeirão Preto, Pelotas, and São Luís) to assess dietary intake of adolescents from São Luís, Maranhão. The research was developed with 152 adolescents aged 18 and 19 years. For the validation of the FFQ, the average of three 24-hour recalls (24HRs) was used as the reference method. The mean and standard deviation of energy and nutrient intake extracted from the surveys were estimated. The paired Student''s t-test was used to verify the differences between the instruments. Pearson correlation coefficient, intraclass correlation coefficient (ICC), weighted Kappa, and the Bland-Altman plot were calculated in order to measure the agreement. The study adopted a level of significance <5%. Compared with the three 24HRs, the FFQ overestimated the consumption of most nutrients. Energy-adjusted and de-attenuated concordance Pearson correlation coefficients ranged from 0.06 to 0.43, and correlations were significant for iron, calcium, riboflavin, sodium, saturated fat, niacin, and vitamin C. The energy-adjusted and de-attenuated ICCs ranged from 0.01 to 0.31, and the weighted Kappa ranged from 0.01 to 0.46. The analyses of agreement were significant for vitamin C, fiber, calcium, riboflavin, niacin, sodium, lipids, and iron. In conclusion, the FFQ presented acceptable relative validity for lipids, saturated fatty acids, fiber, calcium, iron, riboflavin, niacin, vitamin C, and sodium. This instrument will be useful in studies about food consumption of adolescents in São Luís, Maranhão.  相似文献   
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ObjectiveTo assess the clinical usefulness and value of the 5 models for the prediction of acute kidney injury (AKI), severe AKI which renal replacement treatment was needed (RRT-AKI) and death after cardiac surgery procedures in Chinese patients. Methods One thousand and sixty - seven patients who underwent cardiac surgery procedures in the department of cardiac surgery in the Zhongshan Hospital, Fudan University between May 2010 and January 2011 were involved in this research. The predicting value for AKI (AKICS), RRT-AKI (Cleveland, SRI and Mehta score) and death (EURO score) after cardiac surgery procedures was evaluated by Hosmer-Lemeshow goodness-of-fit test for the calibration and area under receiver operation characteristic curve (AUROC) for the discrimination. ResultsThe incidence of AKI was 20.34%(217/1067), and 63.13% of their renal function recovered completely. The incidence of RRT-AKI was 3.56%(38/1067) and the mortality of AKI and RRT - AKI was 9.68%(21/217) and 44.73%(17/38) respectively. The total mortality was 3.28%(35/1067). The discrimination and calibration for the prediction of AKI of AKICS were low. For the prediction of RRT-AKI, the discrimination and calibration of Cleveland score were high enough, but the predicated value was lower than the real value (1.70% vs 3.86%). The discrimination of Mehta score and the calibration of SRI were low. The discrimination and calibration for the prediction of death of EURO score was low. ConclusionAccording to the 2012 KDIGO AKI definition, none of the 5 models above is good at predicting AKI after cardiac surgery procedures. Cleveland score has been validated to have a proper impact on predicting RRT-AKI after cardiac surgery procedures, but the predicting value is still in doubt. EURO score has been validated to have an inaccurate predicting value for death after cardiac surgery procedures.  相似文献   
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Recently, one of the world’s leading scientific and technical advisory groups, the U.S. President’s Council of Advisors on Science and Technology (or PCAST), published an assessment of the research supporting several forensic science procedures in regular use. PCAST was particularly interested in pattern recognition or comparison procedures, specifically: simple and mixed DNA profiles; bite marks; latent fingerprints; firearms; footwear; and hair analysis. In its report and recommendations PCAST emphasised the primacy of validation. In response, the Council of the Australian and New Zealand Forensic Science Society produced a short statement suggesting that the PCAST report has limited application to forensic science in Australia and New Zealand. This short commentary offers an alternative perspective.  相似文献   
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