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11.
Arterial spin labeling (ASL) imaging is a powerful magnetic resonance imaging technique that allows to quantitatively measure blood perfusion non-invasively, which has great potential for assessing tissue viability in various clinical settings. However, the clinical applications of ASL are currently limited by its low signal-to-noise ratio (SNR), limited spatial resolution, and long imaging time. In this work, we propose an unsupervised deep learning-based image denoising and reconstruction framework to improve the SNR and accelerate the imaging speed of high resolution ASL imaging. The unique feature of the proposed framework is that it does not require any prior training pairs but only the subject's own anatomical prior, such as T1-weighted images, as network input. The neural network was trained from scratch in the denoising or reconstruction process, with noisy images or sparely sampled k-space data as training labels. Performance of the proposed method was evaluated using in vivo experiment data obtained from 3 healthy subjects on a 3T MR scanner, using ASL images acquired with 44-min acquisition time as the ground truth. Both qualitative and quantitative analyses demonstrate the superior performance of the proposed txtc framework over the reference methods. In summary, our proposed unsupervised deep learning-based denoising and reconstruction framework can improve the image quality and accelerate the imaging speed of ASL imaging.  相似文献   
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目的 探讨血液肿瘤患者接受化疗后发生肛周感染的危险因素。方法 采用回顾性病例对照研究的方法,对四川省某三级甲等医院血液内科2020年12月—2021年5月收治的进行化疗的348例血液肿瘤住院患者相关资料(人口学特征、疾病特征、医疗及护理病例记录、实验室检查结果)予以回顾性分析,根据出院诊断发生肛周感染的病例作为病例组,其余病例作为对照组,统计血液肿瘤患者接受化疗后肛周感染的发生率,采用单因素分析和二元Logistic回归分析肛周感染的危险因素。结果 348例血液肿瘤化疗患者,发生肛周感染35例,感染率为10.1%;Logistic回归分析显示,年龄<60岁(OR=8.776,P=0.039)、痔疮史(OR=7.733,P<0.001)、肛周感染史(OR=14.981,P<0.001)、腹泻(OR=3.893,P=0.019)及白细胞计数<1×109/L(OR=6.851,P=0.002)是血液肿瘤患者接受化疗后发生肛周感染的独立危险因素。结论 血液肿瘤患者接受化疗后肛周感染的发生率较高,年龄<60岁、痔疮史、肛周感染史、腹泻、白细胞计数<1×109/L导致血液肿瘤化疗患者肛周感染率增加,在护理化疗期的血液肿瘤患者过程中,应该结合肛周感染的危险因素,采取针对性干预措施,降低肛周感染发生率。  相似文献   
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ObjectivesTo determine which nursing home (NH) resident-level admission characteristics are associated with potentially preventable emergency department (PPED) transfers.DesignWe conducted a population-level retrospective cohort study on NH resident data collected using the Resident Assessment Instrument-Minimum Data Set Version 2.0 and linked to the National Ambulatory Care Reporting System for ED transfers.SettingWe used all NH resident admission assessments from January 1, 2017, to December 31, 2018, in Ontario.ParticipantsThe cohort included the admission assessment of 56,433 NH residents.MethodsPPED transfers were defined based on the International Classification of Disease, Version 10 (Canadian) We used logistic regression with 10-fold cross-validation and computed average marginal effects to identify the association between resident characteristics at NH admission and PPED transfers within 92 days after admission.ResultsOverall, 6.2% of residents had at least 1 PPED transfer within 92 days of NH admission. After adjustment, variables that had a prevalence of 10% or more that were associated with a 1% or more absolute increase in the risk of a PPED transfer included polypharmacy [of cohort (OC) 84.4%, risk difference (RD) 2.0%], congestive heart failure (OC 29.0%, RD 3.0%), and renal failure (OC 11.6%, RD 1.2%). Female sex (OC 63.2%, RD -1.3%), a do not hospitalize directive (OC 24.4%, RD -2.6%), change in mood (OC 66.9%, RD -1.2%), and Alzheimer's or dementia (OC 62.1%, RD -1.2%) were more than 10% prevalent and associated with a 1% or more absolute decrease in the risk of a PPED.Conclusions and ImplicationsThough many routinely collected resident characteristics were associated with a PPED transfer, the absence of sufficiently discriminating characteristics suggests that emergency department visits by NH residents are multifactorial and difficult to predict. Future studies should assess the clinical utility of risk factor identification to prevent transfers.  相似文献   
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BackgroundPre-pregnancy obesity is a well-recognized risk factor for gestational diabetes mellitus (GDM). There is a continuity of obesity from childhood to adolescence and then adulthood. However, it is unknown whether early childhood obesity predicts GDM.MethodsWe investigated the prospective association of childhood triceps skinfold thickness and body mass index (BMI) with GDM risk among women from the Mater-University of Queensland Study of Pregnancy (MUSP), a multigenerational cohort study. A multiple logistic regression model was applied to estimate the odds of experiencing GDM by childhood skinfold thickness and BMI.ResultsOut of 552 women in the study for whom data were available on triceps skinfold thickness and BMI at average age 5 (range 3–7) years old, 52 (9.42%) developed GDM by average age 30 (range 28–33) years. We found that the risk of developing GDM was greater among women who had greater skinfold thickness but not greater BMI at age 5 years. Women who were classified as overweight or obese based on skinfold thickness at age 5 years had an increased odds ratio of GDM compared to women who had normal skinfold thickness. This association remained significant after adjustment for the potential confounders (OR 2.74; 95% confidence interval = 1.28–5.86).ConclusionThe risk of developing GDM was associated with higher skinfold thickness at age 5 years.  相似文献   
15.
BackgroundIn the United States nearly 20% of children ages 12–17 have developmental disorders. Some attain population-based developmental milestones after a delay, or increase functioning through special education, medication, technology, or therapy. Others have severe lasting impairments. An indicator identifying those groups in surveys of adults could help shape policies to improve lives.HypothesesWe hypothesized that survey histories of special education could indicate functional status levels.MethodsData were from the nationally representative Panel Study of Income Dynamics (1997–2017, n = 2745). With measures of diagnoses, behaviors, functional status, service use, and adult outcomes, we tested three special education groups as indicators of: (1) no impairment (no special education), (2) disorders, developmental diagnoses that adversely affect educational performance, but with development after a period of delay or only moderate disability, indicated by transfer from special education; and (3) severe lasting disability, the diagnoses combined with life-long needs for supports or services, with limitations in areas including self-care, mobility, and capacity for independent living, indicated by special education in the individual's final year of school.ResultsAcross the special education groups, from no impairment to severe lasting disability, there were trends of: increasing severe and lasting disability (respectively 4.8%, 35.6%, 76.4%); increasing special services use (13.5%, 43.1%, 83.7%); increasing severe emotional disorders (2.3%, 11.3%, 17.9%); lower percentages attaining at least an associate's degree by age 25 (42.1%, 20.7%, and 8.9%); and more chronic diseases.ConclusionsSpecial education histories provide a useful indicator of developmental disability impairment levels in adults.  相似文献   
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One in five children in the UK are affected by domestic violence and abuse. However, primary care clinicians (GPs and nurses) struggle to effectively identify and support children and young people living in homes where it is present. The IRIS+ (Enhanced Identification and Referral to Improve Safety) training and advocacy support intervention aimed to improve how clinicians respond to children and young people affected by domestic violence and abuse. IRIS+ training was delivered as part of a feasibility study to four general practices in an urban area in England (UK). Our mixed method design included interviews and questionnaires about the IRIS+ intervention with general practice patients, including children and young people as well as with clinicians and advocacy service providers. We collected the number of identifications and referrals by clinicians of children experiencing domestic violence and abuse through a retrospective search of medical and agency records 10 months after the intervention. Forty-nine children exposed to domestic violence and abuse were recorded in medical records. Thirty-five children were referred to a specialist domestic violence and abuse support service over a period of 10 months. Of these, 22 received direct or indirect support. The qualitative findings indicated that children benefitted from being referred by clinicians to the service. However, several barriers at the patient and professional level prevented children and young people from being identified and supported. Some of these barriers can be addressed through modifications to professional training and guidance, but others require systematic and structural changes to the way health and social care services work with children affected by domestic violence and abuse.  相似文献   
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