首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   42023篇
  免费   3830篇
  国内免费   1400篇
耳鼻咽喉   471篇
儿科学   351篇
妇产科学   250篇
基础医学   3862篇
口腔科学   1131篇
临床医学   4927篇
内科学   2614篇
皮肤病学   372篇
神经病学   1861篇
特种医学   1317篇
外国民族医学   1篇
外科学   2591篇
综合类   8721篇
现状与发展   2篇
预防医学   4973篇
眼科学   651篇
药学   6735篇
  180篇
中国医学   5454篇
肿瘤学   789篇
  2024年   140篇
  2023年   637篇
  2022年   1176篇
  2021年   2056篇
  2020年   1697篇
  2019年   1157篇
  2018年   1112篇
  2017年   1413篇
  2016年   1477篇
  2015年   1513篇
  2014年   2953篇
  2013年   3043篇
  2012年   2874篇
  2011年   3064篇
  2010年   2362篇
  2009年   1975篇
  2008年   2013篇
  2007年   2235篇
  2006年   1802篇
  2005年   1553篇
  2004年   1300篇
  2003年   1107篇
  2002年   922篇
  2001年   828篇
  2000年   707篇
  1999年   636篇
  1998年   541篇
  1997年   468篇
  1996年   468篇
  1995年   438篇
  1994年   421篇
  1993年   352篇
  1992年   341篇
  1991年   289篇
  1990年   255篇
  1989年   240篇
  1988年   230篇
  1987年   212篇
  1986年   186篇
  1985年   231篇
  1984年   162篇
  1983年   116篇
  1982年   138篇
  1981年   86篇
  1980年   75篇
  1979年   50篇
  1978年   50篇
  1977年   38篇
  1976年   40篇
  1974年   17篇
排序方式: 共有10000条查询结果,搜索用时 171 毫秒
1.
以“七麦数据”网站收录的中医移动医疗App作为研究对象,采用网络调查法和文献分析法,根据“七麦数据”对移动医疗App的分类,结合中医移动医疗App的信息服务内容和特点,将筛选出的中医移动医疗App划分为医疗健康类、中医养生类、知识传播类、全面综合类,并根据“七麦数据”网站中对各类中医移动医疗App的打分及累计下载量筛选出最具代表性的12款中医移动医疗App,从全面性、人性化、安全性、实用性4个一级指标和40个二级指标对其信息服务现状进行评价,指出当前中医移动医疗App信息服务存在的问题并提出建议。  相似文献   
2.
《Orthopaedics and Trauma》2022,36(6):304-310
Congenital vertical talus (CVT) is a rare foot deformity that presents with a rigid flat foot at birth. CVT can present as an isolated abnormality in the newborn, however in at least 50% of cases in association with other conditions. Full neuro-axial imaging is essential to detect any associated neurologic problems. Radiographs of the foot, including forced plantar and dorsiflexion laterals, are diagnostic. Gold standard modern treatment uses the Dobbs method of serial manipulation and casting with minimally-invasive stabilization of the talonavicular joint and Achilles tendon tenotomy.  相似文献   
3.
《Clinical neurophysiology》2021,132(10):2357-2364
ObjectivesTo investigate the subcortical somatosensory evoked potentials (SEPs) to electrical stimulation of either muscle or cutaneous afferents.MethodsSEPs were recorded in 6 patients suffering from Parkinson’s disease (PD) who underwent electrode implantation in the pedunculopontine (PPTg) nucleus area. We compared SEPs recorded from the scalp and from the intracranial electrode contacts to electrical stimuli applied to: 1) median nerve at the wrist, 2) abductor pollicis brevis motor point, and 3) distal phalanx of the thumb. Also the high-frequency oscillations (HFOs) were analysed.ResultsAfter median nerve and pure cutaneous (distant phalanx of the thumb) stimulation, a P1-N1 complex was recorded by the intracranial lead, while the scalp electrodes recorded the short-latency far-field responses (P14 and N18). On the contrary, motor point stimulation did not evoke any low-frequency component in the PPTg traces, nor the N18 potential on the scalp. HFOs were recorded to stimulation of all modalities by the PPTg electrode contacts.ConclusionsStimulus processing within the cuneate nucleus depends on modality, since only the cutaneous input activates the complex intranuclear network possibly generating the scalp N18 potential.SignificanceOur results shed light on the subcortical processing of the somatosensory input of different modalities.  相似文献   
4.
《Clinical neurophysiology》2021,132(9):2003-2011
ObjectiveA large N20 and P25 of the median nerve somatosensory evoked potential (SEP) predicts short survival in amyotrophic lateral sclerosis (ALS). We investigated whether high frequency oscillations (HFOs) over N20 are enlarged and associated with survival in ALS.MethodsA total of 145 patients with ALS and 57 healthy subjects were studied. We recorded the median nerve SEP and measured the onset-to-peak amplitude of N20 (N20o-p), and peak-to-peak amplitude between N20 and P25 (N20p-P25p). We obtained early and late HFO potentials by filtering SEP between 500 and 1 kHz, and measured the peak-to-peak amplitude. We followed up patients until endpoints (death or tracheostomy) and analyzed the relationship between SEP or HFO amplitudes and survival using a Cox analysis.ResultsPatients showed larger N20o-p, N20p-P25p, and early and late HFO amplitudes than the control values. N20p-P25p was associated with survival periods (p = 0.0004), while early and late HFO amplitudes showed no significant association with survival (p = 0.4307, and p = 0.6858, respectively).ConclusionsThe HFO amplitude in ALS is increased, but does not predict survival.SignificanceThe enlarged HFOs in ALS might be a compensatory phenomenon to the hyperexcitability of the sensory cortex pyramidal neurons.  相似文献   
5.
Objective: The objective of this study is to evaluate the efficacy and safety of the clearing the lung and dissipating phlegm method in the treatment of acute exacerbation of chronic obstructive pulmonary disease(COPD) and to provide evidence for the treatment of the disease. Materials and Methods: Literature was searched from the United States National Library of Medicine(PubMed), Embase, Cochrane Library, China National Knowledge Infrastructure, Wanfang Database(Wanfang), and the Full?Text Database of Chinese Scientific and Technical Periodicals(VIP).A comprehensive collection was made of randomized controlled trials(RCTs) before June 2018, in which the treatment groups used either the clearing the lung and dissipating phlegm formulas only or combined it with routine Western medicine therapy, and the control group adopted routine Western medicine therapy only for the acute exacerbation of COPD. The Cochrane risk of bias method was used to evaluate the quality of the literature. The data were analyzed and retrieved independently by two reviewers before meta?analysis was carried out with RevMan 5.3 software to evaluate the primary outcome measures, including the total clinical effective rate, and the secondary outcome measures such as the pulmonary function(forced vital capacity [FVC], forced expiratory volume in the 1 s [FEV1], percentage of FEV1 [FEV1%], and FEV1/FVC)and blood gases(PaO_2 and PaCo_2). Results: A total of 13 RCTs involving 990 patients(496 in the treatment group and 494 in the control group)were included in this study. Meta?analysis revealed significant difference in the efficacy of the group that adopted solely the routine Western medicine method and the group that combined the Western medicine with the clearing the lung and dissipating phlegm method. Outcome measures including the pulmonary function(FVC, FEV1, FEV1%, and FEV1/FVC) and the blood gases(PaO_2 and PaCo_2) were significantly improved as compared to the control group(P 0.00001). However, adverse effects in the treatment group using combined traditional Chinese medicine were not reported due to the short observation time of the study. Conclusion: The clearing the lung and dissipating phlegm method can improve the efficacy in the treatment of acute exacerbation of COPD, the outcome measures of the pulmonary function and the blood gases,as well as the life quality of the patients. However, due to the fact that the existing studies are generally of poor quality in which randomization and its implementation were not properly carried out, more high?quality RCTs are necessary to confirm the findings of this study.  相似文献   
6.
Radiodermatitis is one of the commonest side effects of radiotherapy. They are usually assessed by semi‐quantitative clinical scores, which are not validated and may be subject to inter‐observer variability. A few previous studies suggested that high‐frequency ultrasonography (HF‐USG) is useful in the assessment of the acute phase of radiation dermatitis in breast cancer patients. (a) To monitor skin changes by HF‐USG during the course of radiotherapy due to head and neck cancers, and (b) to determine whether there is any connection between skin sonograms and the skin scoring criteria. This prospective, observational study includes patients diagnosed with head and neck cancers, treated with radiotherapy or concomitant chemoradiation. The final analysis includes six patients. In every patient, the HF‐USG as well as dermatological assessment (target lesion score—TLS and CACE v. 4.0) were performed 4×: before, in the middle, day after, and 3 months after radiotherapy. There were significant differences between non‐irradiated skin thickness and thickness of skin with clinically obvious radiodermatitis (TLS grade 1‐4; P < .0001), as well as between irradiated, unchanged skin thickness (TLS grade 0) and thickness of skin with clinically obvious radiodermatitis (TLS grade 1‐4; P = .0002). There was no significant difference between non‐irradiated and irradiated, unchanged skin thickness (TLS grade 0; P = .9318). In four patients, we demonstrated subepidermal low echogenic band (SLEB). HF‐USG can be useful tool to noninvasive and objective assessment of skin changes during radiotherapy.  相似文献   
7.
Dietary assessment in infants is challenging but necessary to understand the relationship between nutrition and growth and development. Currently no simple, validated methods exist to assess nutrient intake in New Zealand (NZ) infants. Therefore, this study aimed to assess the relative validity and reproducibility of a Complementary Food Frequency Questionnaire (CFFQ) to determine nutrient intakes of NZ infants. Ninety‐five parent–infant pairs (infant age 10 ± 1 months) completed the CFFQ twice (CFFQ‐1 and CFFQ‐2), 4 weeks apart (to assess reproducibility). A 4‐day weighed food record (4dWFR) was collected between CFFQ administrations (to assess validity). Validity and reproducibility were assessed for intakes of energy and 18 nutrients using Bland–Altman analysis, Pearson's correlation coefficients, cross‐classification, and weighted Kappa (κ). The CFFQ showed acceptable validity: Nutrients from the CFFQ were comparable with the 4dWFR (bias, 9–28%), correlation between methods ranged from r = .18 (saturated fat) to r = .81 (iron; mean r = .52), 54% (mean) of participants were correctly classified (range 39% to 67%), and 7.1% (mean) misclassified into opposite tertiles (range 2.1% to 14.7%). There was acceptable agreement between the CFFQ and 4dWFR (κ = 0.20–0.60). The CFFQ showed good reproducibility: Correlations ranged from r = .34 (folate) to r = .80 (zinc); for 16 nutrients, >50% of participants were correctly classified, and for all nutrients, <10% of participants were grossly misclassified. All nutrients showed acceptable to good agreement (κ > 0.20). The CFFQ has acceptable relative validity and good reproducibility for assessing nutrient intake in NZ infants aged 9–12 months, making it a useful tool for use in future research.  相似文献   
8.
健康状态的辨识是把握健康的前提。当前学界已存在专家辨识模式、标准辨识模式、数字辨识模式、智能辨识模式以及微观辨识模式等。联合多种辨识方法,构建健康状态辨识体系,形成常态与动态结合、主观与客观结合、人机互参的中医健康状态个体化辨识方法是研究的趋势所在。文章对未来的研究方向进行展望,探讨了多元辨识模式、远程辨识模式、终身辨识模式、自动辨识模式的思路方法,以期促进全民健康事业,助力"健康中国"战略。  相似文献   
9.
10.
目的:观察清肝解郁和健脾补肾法治疗肝火上亢型慢性肾衰(CRF)合并高血压患者的临床效果。方法:选取2016年6月至2018年6月京东誉美医院收治的肝火上亢型CRF合并高血压患者90例作为研究对象,按照随机数字表法随机分为对照组和观察组,每组45例。对照组给予口服硝苯地平控释片治疗,观察组在对照组治疗基础上给予清肝解郁、健脾补肾汤治疗,每4周为1个疗程,均治疗3个疗程。比较治疗前后中医症状评分、收缩压(SBP)、舒张压(DBP)变化;比较2组临床疗效;比较治疗前后肾功能指标:尿素氮(BUN)、血肌酐(Scr)、24 h尿蛋白定量(24 hPRO);统计治疗期间2组不良反应发生情况。结果:治疗前观察组与对照组中医症状评分、SBP、DBP、BUN、Scr、24 hPRO比较,差异均无统计学意义(P>0.05),治疗后2组患者中医症状评分、SBP、DBP、BUN、Scr、24 hPRO均显著降低(P<0.05),观察组均低于对照组,差异有统计学意义(P<0.05);2组临床疗效比较,差异有统计学意义(P<0.05),且观察组总有效率显著高于对照组,差异有统计学意义(P<0.05);观察组和对照组不良反应发生率分别为2.22%和6.67%,2组比较差异无统计学意义(P>0.05)。结论:清肝解郁、健脾补肾法辅助治疗肝火上亢型CRF合并高血压疗效确切,可较好控制血压,并且可显著改善肾功能,减少不良反应发生情况。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号