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1.
《Radiography》2022,28(4):964-972
IntroductionThe British Institute of Radiology (BIR) and American Association of Physicists in Medicine (AAPM) have recommended that gonad shielding is no longer used during pelvic X-ray examinations. The BIR guidance states that shielding may still be considered for use on males, but should not be used on females. This paper aimed to evaluate if this decision was supported by evidence from practice, by comparing the accuracy of gonad shield placement in paediatric males and females.MethodsA systematic review of databases including EMBASE, MEDLINE and PubMed was performed in February 2021. Studies were considered eligible if they provided data on the use of gonad shielding during pelvic X-ray examinations on male and female patients under the age of 18. Nine studies met the inclusion criteria and data extraction was performed. Quality appraisal was undertaken, and a meta-analysis of shielding accuracy was performed on seven studies.ResultsThe results from the meta-analysis (2187 total radiographs) demonstrated that female patients were significantly more likely (OR 1.38, 95% CI 0.88–1.87) than males to have gonad shields placed inaccurately (p value < 0.001).ConclusionGonad shield placement on paediatric female patients is significantly less accurate than on males, and so the results support the AAPM and BIR guidance to stop the practice for females. Shield application may also be frequently inaccurate for males, but the review does not provide clear evidence for or against continuing the practice for males.Implications for practiceDiscontinuing the use of gonad shields in paediatric pelvic radiography on female patients is supported. Any continued use on male patients, or for reasons such as psychological reassurance, should be subject to enhanced training and audit to ensure benefits outweigh any risks.  相似文献   
2.
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   
3.

Background

European guidelines recommend targeted temperature management (TTM) in post-cardiac arrest care. A large multicentre clinical trial, however, showed no difference in mortality and neurological outcome when comparing hypothermia to normothermia with early treatment of fever. The study results were valid given a strict protocol for the assessment of prognosis using defined neurological examinations. With the current range of recommended TTM temperatures, and applicable neurological examinations, procedures may differ between hospitals and the variation of clinical practice in Sweden is not known.

Aim

The aim of this study was to investigate current practice in post-resuscitation care after cardiac arrest as to temperature targets and assessment of neurological prognosis in Swedish intensive care units (ICUs).

Methods

A structured survey was conducted by telephone or e-mail in all Levels 2 and 3 (= 53) Swedish ICUs during the spring of 2022 with a secondary survey in April 2023.

Results

Five units were not providing post-cardiac arrest care and were excluded. The response rate was 43/48 (90%) of the eligible units. Among the responding ICUs, normothermia (36–37.7°C) was applied in all centres (2023). There was a detailed routine for the assessment of neurological prognosis in 38/43 (88%) ICUs. Neurological assessment was applied 72–96 h after return of spontaneous circulation in 32/38 (84%) units. Electroencephalogram and computed tomography and/or magnetic resonance imaging were the most common technical methods available.

Conclusion

Swedish ICUs use normothermia including early treatment of fever in post-resuscitation care after cardiac arrest and almost all apply a detailed routine for the assessment of neurological prognosis. However, available methods for prognostic evaluation varies between hospitals.  相似文献   
4.
5.
Frameworks for deriving occupational exposure limits (OELs) and OEL-analogue values (such as derived-no-effect levels [DNELs]) in various regulatory areas in the EU and at national level in Germany were analysed. Reasons for differences between frameworks and possible means of improving transparency and harmonisation were identified. Differences between assessment factors used for deriving exposure limits proved to be one important reason for diverging numerical values. Distributions for exposure time, interspecies and intraspecies extrapolation were combined by probabilistic methods and compared with default values of assessment factors used in the various OEL frameworks in order to investigate protection levels. In a subchronic inhalation study showing local effects in the respiratory tract, the probability that assessment factors were sufficiently high to protect 99% and 95% of the target population (workers) from adverse effects varied considerably from 9% to 71% and 17% to 87%, respectively, between the frameworks. All steps of the derivation process, including the uncertainty associated with the point of departure (POD), were further analysed with two examples of full probabilistic assessments. It is proposed that benchmark modelling should be the method of choice for deriving PODs and that all OEL frameworks should provide detailed guidance documents and clearly define their protection goals by stating the proportion of the exposed population the OEL aims to cover and the probability with which they intend to provide protection from adverse effects. Harmonisation can be achieved by agreeing on the way to perform the methodological steps for deriving OELs and on common protection goals.  相似文献   
6.
研制一种适合野外急救使用的多功能气道防护屏,以解决气道相关操作时患者呼吸道分泌物喷溅的问题。多功能气道防护屏由一个底部为直角"目"型框架,两个体部为直角"∏"形不锈钢支架,一个双层开放气道体位调节垫和一个透明塑料罩组成,具有可拆卸、可折叠及视野清晰的多功能呼吸道防护装备;防护屏设计具有可调节头颈后仰卧位,能充分显露气道提高气管插管成功率,可提高医护人员安全性和满意度;在防护屏内建立人工气道、实施各种气道护理,可防止患者呼吸道分泌物喷溅,使周围环境处于相对安全状态,有效避免职业暴露及交叉感染。  相似文献   
7.
《Vaccine》2019,37(24):3190-3198
The development of a group B Streptococcus (GBS) vaccine for maternal immunization constitutes a global public health priority, to prevent GBS-associated early life invasive disease, stillbirth, premature birth, maternal sepsis, adverse neurodevelopmental consequences, and to reduce perinatal antibiotic use. Sample size requirements for the conduct of a randomized placebo-controlled trial to assess vaccine efficacy against the most relevant clinical endpoints, under conditions of appropriate ethical standards of care, constitute a significant obstacle on the pathway to vaccine availability. Alternatively, indirect evidence of protection based on immunologic data from vaccine and sero-epidemiological studies, complemented by data from opsonophagocytic in vitro assays and animal models, could be considered as pivotal data for licensure, with subsequent confirmation of effectiveness against disease outcomes in post-licensure evaluations. Based on discussions initiated by the World Health Organization we present key considerations about the potential role of correlates of protection towards an accelerated pathway for GBS vaccine licensure and wide scale use. Priority activities to support progress to regulatory and policy decision are outlined.  相似文献   
8.
目的探讨神经节苷脂联合苯巴比妥治疗新生儿缺氧缺血性脑病的临床疗效及对新生儿神经功能的影响。方法选取2017年3月-2019年3月本院收治的缺氧缺血性脑病新生儿106例,随机分为两组,对照组应用苯巴比妥治疗,研究组应用神经节苷脂联合苯巴比妥治疗。比较临床治疗有效率、神经功能恢复效果、治疗前后NBNA评分统计。结果研究组临床治疗有效率、不同程度的时间恢复效果、治疗后NBNA评分均高于对照组(P<0.05)。结论治疗新生儿缺氧缺血性脑病治疗过程当中,神经节苷脂联合苯巴比妥的治疗效果理想,可改善新生儿神经功能。  相似文献   
9.
In the “basic” approach, medical expenses are catastrophic if they exceed a prespecified percentage of consumption or income; the approach tells us if expenses cause a large percentage reduction in living standards. The ability‐to‐pay (ATP) approach defines expenses as catastrophic if they exceed a prespecified percentage of consumption less expenses on nonmedical necessities or an allowance for them. The paper argues that the ATP approach does not tell us whether expenses are large enough to undermine a household's ability to purchase nonmedical necessities. The paper compares the income‐based and consumption‐based variants of the basic approach, and shows that if the individual is a borrower after a health shock, the income‐based ratio will exceed the consumption‐based ratio, and both will exceed the more theoretically correct Flores et al. ratio; whereas if the individual continues to be a saver after a health shock, the ordering is reversed and the income‐based ratio may not overestimate Flores et al.'s ratio. Last, the paper proposes a lifetime money metric utility (LMMU) approach defining medical expenses as catastrophic in terms of their lifetime consequences. Under certain assumptions, the LMMU and Flores et al. approaches are identical, and neither requires data on how households finance their medical expenses.  相似文献   
10.
肺癌患者的细胞免疫、体液免疫、红细胞免疫等状况较正常人均存在着不同程度的低下。目前早中期患者肺癌的首选治疗方式仍然是手术切除治疗。虽然切除肿瘤可以逐渐消除瘤体本身造成的免疫抑制,但手术创伤引发的机体应激反应、神经内分泌变化、疼痛的刺激以及麻醉药物的使用在术后一段时间内反而会加重免疫抑制。因此针对围术期内多个治疗环节加以改进,可以有助于患者术后免疫功能的恢复,减少肿瘤复发、转移的几率。具体措施包括术前给予参芪扶正注射液、番茄红素、胸腺肽等药物以及预先给予适当的心理疏导以提升免疫力;术中更多的运用微创胸腔镜技术并在全身麻醉时联用硬膜外麻醉;围术期采用多模式联合镇痛,术前给予氟比洛芬酯等非甾体类抗炎药物开展超前镇痛,术后给予静脉持续自控镇痛时辅用地佐辛等药物或与肋间神经阻滞相结合,或改用硬膜外自控镇痛、自控椎旁神经阻滞等方法镇痛;此外术后建议给予患者早期营养支持,尽量减少不必要的输血,需要输血时使用辐照成分输血。  相似文献   
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