全文获取类型
收费全文 | 17779篇 |
免费 | 924篇 |
国内免费 | 185篇 |
专业分类
耳鼻咽喉 | 290篇 |
儿科学 | 620篇 |
妇产科学 | 572篇 |
基础医学 | 925篇 |
口腔科学 | 1152篇 |
临床医学 | 2603篇 |
内科学 | 680篇 |
皮肤病学 | 103篇 |
神经病学 | 1671篇 |
特种医学 | 1323篇 |
外国民族医学 | 1篇 |
外科学 | 3357篇 |
综合类 | 1989篇 |
一般理论 | 1篇 |
预防医学 | 1636篇 |
眼科学 | 800篇 |
药学 | 877篇 |
28篇 | |
中国医学 | 153篇 |
肿瘤学 | 107篇 |
出版年
2024年 | 42篇 |
2023年 | 328篇 |
2022年 | 426篇 |
2021年 | 694篇 |
2020年 | 656篇 |
2019年 | 591篇 |
2018年 | 561篇 |
2017年 | 678篇 |
2016年 | 595篇 |
2015年 | 589篇 |
2014年 | 1120篇 |
2013年 | 1400篇 |
2012年 | 902篇 |
2011年 | 1040篇 |
2010年 | 829篇 |
2009年 | 900篇 |
2008年 | 856篇 |
2007年 | 859篇 |
2006年 | 791篇 |
2005年 | 749篇 |
2004年 | 596篇 |
2003年 | 459篇 |
2002年 | 420篇 |
2001年 | 337篇 |
2000年 | 291篇 |
1999年 | 250篇 |
1998年 | 220篇 |
1997年 | 200篇 |
1996年 | 176篇 |
1995年 | 167篇 |
1994年 | 138篇 |
1993年 | 99篇 |
1992年 | 102篇 |
1991年 | 77篇 |
1990年 | 81篇 |
1989年 | 60篇 |
1988年 | 46篇 |
1987年 | 53篇 |
1986年 | 50篇 |
1985年 | 84篇 |
1984年 | 76篇 |
1983年 | 40篇 |
1982年 | 69篇 |
1981年 | 55篇 |
1980年 | 47篇 |
1979年 | 21篇 |
1978年 | 14篇 |
1977年 | 18篇 |
1976年 | 11篇 |
1975年 | 15篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Child benefits are typically paid from birth. This paper asks whether starting universal child benefits in pregnancy leads to improvements in infant health. Leveraging administrative birth registry and hospital microdata from England and Wales, I study the effects of the Health in Pregnancy Grant, a universal conditional cash transfer equivalent to three months of child benefit (190 GBP) as a lump sum to pregnant mothers from 2009 to 2011. I exploit quasi-experimental variation in eligibility with a regression discontinuity design in the date of birth of the baby. I find that the policy increased birth weight by 8–12 grams on average, reduced low birth weight (2500 g) by 3-6 percent and decreased prematurity by 9–11 percent. Younger mothers, particularly those living in deprived areas, benefit the most. I present evidence that the mechanisms are unlikely to be antenatal care, nutrition or smoking, with reductions in stress remaining a possible explanation. 相似文献
2.
Yann Auxéméry 《L'évolution Psychiatrique》2021,86(2):375-397
ObjectivesTrauma appears within the discourse of mentally injured people, materializing what we have recently defined as “post traumatic psycholinguistic syndrome” (SPLIT). Translating unspeakability, revival, and dissociation, this clinical entity associates three significant disturbances : traumatic anomia (missing words, reduction of the elocutionary flow, deictic gestures, etc.); linguistic repetitions (of words and phrases, verbal intrusions, echophrasias, etc.); and phrasal and discursive disorganization (incomplete sentences, tense discordance, dysfluence, lack of logical connectors, etc.). What are the causes of these semiological and psycholinguistic expressions? What are their psychological and/or neuropsychological processes? It is time to come up with a new concept intended to go beyond the previous models in order to better identify people suffering from post-traumatic mental disorders, to better organize and evaluate psychotherapeutic care, and also to help practitioners collaborate more effectively on these first two goals. But how to evoke, affirm, or speak out about the consequences of unspeakability? Nothing is more apparently contradictory than wanting to define the language void. How to account for the fractures of psychic trauma in discourse? Nothing is more uncertain than to try to organize the upheavals, the disorders caused by dissociation in language. Finally, how to specify the reiteration of the trauma using words and sentences without this modeling being dissociative or repetitive? Today, thanks to a psycholinguistic reading, essential dimensions of post-traumatic suffering, hitherto hidden, can be clarified. Why exactly does an event cause trauma in the life of a subject at a given moment in her/his existence? Why is a latency phase structured between the traumatic event and the return of reviviscences under the influence of a re-triggering factor? How to differentiate the notion of dissociation as a normal phenomenon from the so-called traumatic dissociation? How to explain the multiple clinical forms of post-traumatic psychological disorders?MethodsFrom Pierre's clinical history, we chronologically detail the structuring and the consequences of the signified reflection that are constitutive of the psychic trauma: the psycholinguistic tools here help to formulate a new etiopathogenic conception of trauma and its psychological consequences. Then, thanks to Jean's testimony, taking up the retrospective meaning of the clinical analysis from chronic repetition syndrome, we discover the phases of tension regarding signified knowledge, up to the network prior to the traumatic confrontation. Finally, illustrated by Karima's disorder, beyond depersonalization, we explain that the analysis of the disturbances of a singular signified network, and also of an attack on its familial and societal bases, testifies to individual and collective subjectivities.ResultsComing from the real world, and therefore also from the body, the stimuli made up of signals picked up by our senses combine to compose an event that can be objectified by its temporal, spatial, biological, and physico-chemical coordinates. These elements combine into a unit, which is then interpreted by the mind, which attributes meaning to this event, which has become subjective reality. But when the subject is not sufficiently prepared to be confronted with this meaning that appears to be in extreme contradiction with her/his previous cardinal networks of significations, it makes “too much sense:” this irreconcilable hyper-signified (that we call the traumatic signified) results in post-traumatic dissociation. In other words, it is an impossibility of concordance of a signified with certain systems of prior significations that constitutes the pathogenesis of the trauma; and a situation runs a greater risk of being traumatic when it contradicts, or, moreso, endangers some or all of the subject's cardinal meanings. This unbearable signified reflexively blocks the capacities of significations immediately pre- and post-trauma, then dissociates the psychic functions to varying degrees and intensities. The traumatic signified, rejected, becomes unattainable: the stimuli that led to its formation find themselves confined to the state of reviviscences, each replication of which attempts to cross the barrier of inconceivability. Limiting sensory compounds to their raw states without the possibility of representational integration, associative pathways remain blocked. The signifier is referred to a hypo-signifier confined to the infra-linguistic by its confusion with the referent, the “objective and material” components of the traumatic event. Dissociation is therefore only a symptomatic reaction, secondary to the trauma, which it reinforces once again by limiting any possibility of representing the trauma. This dissociation does not involve forgetting the traumatic signified but “protects” the adjacent networks of meanings from it as much as it “keeps” this hypersignified intact, therefore ultimately “protecting” it as well. The traumatic signified persists somewhere, and even ends up being found everywhere: when the networks of meanings turn out to be globally disturbed, the tightest links remain those of the traumatic hypersignified that ultimately governs all the networks of meanings.DiscussionOur insufficient knowledge prevents us from precisely qualifying the architecture of the signified idiosyncratic networks and their evolutionary capacities; we cannot predict, beforehand, the reaction of an individual confronted with a potentially psychotraumatic situation. For most clinical situations, we affirm that the psychological trauma occurs in a psychically healthy subject, that is, not suffering from any psychiatric illness or any obvious psychopathological conflict. Psychotherapy will make it possible to discover the signified, sometimes ancient, origins of a trauma occurring in a singular subject. How was this subjectivity constructed? Beyond individual subjectivity, the intensity of certain confrontations such as serious attacks or macrosocial catastrophes such as genocide, would seem to lead to psychological wounds in any individual, even at the scale of a population. While, throughout existence, each subject produces a system of significations in connection with a unique psychic construction, the latter persists – resulting from, and often remaining overseen by, the community essence of a base of signifying networks, which we call “societal subjectivity.” Here, the psychological trauma can correspond to an individual and “common” injury as a failure of a sharing, or of ancestral beliefs anchored in the collective memory, defining the culture. By the collapse of acquired certainties, the cognitive patterns transmitted by education, language, and everything that establishes one's belonging to a society, trauma shakes the networks of individual and group meanings. Horror has a higher traumatogenic risk, because it defeats the fundamentals of humankind, the foundations of a signified network common to a culture, or even to all cultures, to the human condition. This is the case with murder, rape, torture, wars, genocides. Testifying to an instinct for survival stemming from the biological foundations of every living being, the impossibility of “living death” appears to be anchored in our networks of meanings and is manifested by indescribability, traumatic as such: being deserted by the language collides with the condition of speaking. And yet, it remains possible to say something about it... As a path of progressive desocialization, the occasional loss of the community of language, followed by its lasting traumatic ravages, can be appeased by the reestablishment of a speech link, either within the mind of the subject alone, or promoted by the exchange with others, in a psychotherapeutic setting, for example.ConclusionWhere theoretical discourses have sometimes proved divisive, going beyond the symptoms of indescribability and dissociation, psychodynamic practice today offers to unite. Thanks to psycholinguistic listening, phenomena that have never been explained take on meaning: the singularity of traumatic perception, the chronology of disorders including the latency phase, factors that trigger reviviscences, and the diversity of chronic clinical forms. All these post-traumatic symptoms are consequential to a linguistic wound, a difficulty in accessing meaning, the undermining of two dimensions characterizing and constructing the human being. As much as it integrates extralinguistic determinants, if the traumatic signified is undoubtedly not only speech, language appears the optimal way to identify it as such, while in the same movement appeasing it. The traumatic hypersignified is discovered through clinical analysis and psychotherapy, through deferred action, through the attribution of meaning, through the retrospective reconstruction of an unstable “real,” through a changing narration eternally distancing itself from reviviscences. But what precisely are the mechanisms of effective therapies ? What are the intersubjective links called for in the discussion between patient and practitioner? Could the operations that we call “psychotherapy” be made up of mobilizations of the networks of meanings by speech acts? 相似文献
3.
牙外伤是口腔急诊常见的病症之一,及时准确的牙髓活力判断是正确治疗以利维持美学与功能的重要前提条件。文章通过对牙髓活力的生物学基础、牙髓活力测验方法及评价、外伤牙髓受损类型和牙髓活力特点分析,在国际牙外伤临床治疗指南的方向指导下,结合案例和经验,概括外伤牙活力与实施临床治疗方案的关系,为提高牙外伤的临床诊治思维、科学精准和个性化治疗设计提供支持,具有重要的应用价值。 相似文献
4.
5.
6.
7.
《International journal of oral and maxillofacial surgery》2020,49(7):914-931
Titanium osteosynthesis is currently the fixation system of choice in maxillofacial traumatology. Biodegradable osteosynthesis systems have the ability to degrade in the human body. The aim of this study was to conduct a systematic review, with meta- and trial sequential analyses, to assess the efficacy and morbidity of biodegradable versus titanium osteosynthesis after maxillofacial trauma. MEDLINE, Embase, and CENTRAL were searched for randomized controlled trials and prospective and retrospective controlled studies. Five time periods were studied: perioperative, short-term (0–4 weeks), intermediate (6–12 weeks), long-term (>12 weeks), and overall follow-up. After screening 3542 records, 24 were included. All had a high risk of performance and detection bias due to the nature of the interventions. Meta-analysis showed no differences in efficacy or morbidity between biodegradable and titanium osteosynthesis. The risk of perioperative screw breakage was significantly higher (risk ratio 17.13, 95% confidence interval 2.19–34.18) and the symptomatic plate removal rate lower in the biodegradable group (risk ratio 0.11, 95% confidence interval 0.02–0.57), which was confirmed by the trial sequential analysis. The quality of evidence ranged from very low to moderate. Based on the narrative review and meta-analyses, current evidence shows that biodegradable osteosynthesis is a viable alternative to titanium osteosynthesis when applied in the treatment of maxillofacial trauma, with similar efficacy but significantly lower symptomatic plate removal rates. Perioperative screw breakage occurred significantly more often in the biodegradable group compared to the titanium group. 相似文献
8.
Margaret H. Lauerman Karen Irizarry Clint Sliker Brandon R. Bruns Ronald Tesoriero Thomas M. Scalea Deborah M. Stein 《Injury》2019,50(1):131-136
Background
Current blunt cerebrovascular injury (BCVI) grading grossly differentiates injury characteristics such as luminal stenosis (LS) and aneurysmal disease. The effect of increasing degree of LS beyond the current BCVI grading scale on stroke formation is unknown.Study Design
BCVI over a 3-year period were retrospectively reviewed. To investigate influence of LS beyond the BCVI grading scale within aneurysmal and non-aneurysmal BCVI, grade 2 BCVI were subdivided into BCVI with ≥ 25% and ≤ 50% LS and BCVI with > 50% and ≤ 99% LS. Grade 3 BCVI were subdivided into BCVI with pseudoaneurysm (PSA) without LS and BCVI with PSA and LS. We hypothesized increased LS beyond the current BCVI grade distinctions would be associated with higher rates of stroke formation.Results
312 BCVI were included, of which 140 were carotid BCVI and 172 vertebral BCVI. Sixteen carotid BCVI underwent endovascular intervention (EI) and 19 suffered a stroke. In carotid BCVI stroke rates increased sequentially with BCVI grade except in grade 3. There was a stroke rate of 12% in grade 1 carotid BCVI, 18% in grade 2, 6% in grade 3, and 31% in grade 4. In subgroup analysis for grade 2 carotid BCVI, BCVI with > 50% and ≤ 99% LS had higher rates of stroke (22% vs. 15%, p?=?0.44) than BCVI with ≥ 25% and ≤ 50% LS. In subgroup analysis of grade 3 carotid BCVI, BCVI with PSA and LS had higher rates of stroke (9% vs. 4%, p?=?0.48) than BCVI with PSA without LS. Higher rates of EI in grade 2 carotid BCVI with > 50% and ≤ 99% LS (22% vs. 5%, p?=?0.14) and grade 3 carotid BCVI with PSA and LS (35% vs. 4%, p?=?0.01) were noted in subgroup analysis.Conclusion
Higher percentage LS beyond the currently used BCVI grading scale has a non-significantly increased rate of stroke in both aneurysmal and non-aneurysmal BCVI. Grade 3 BCVI with PSA and LS seems to be a high-risk subgroup. Use of EI confounds modern measurement of stroke risk in higher LS BCVI. 相似文献9.
《Australian critical care》2022,35(4):408-414
BackgroundClinically significant post-traumatic stress symptoms (PTSS) have been reported in up to a quarter of paediatric intensive care unit (PICU) survivors. Ongoing PTSS negatively impacts children's psychological development and physical recovery. However, few data regarding associations between potentially modifiable PICU treatment factors, such as analgosedatives and invasive procedures, and children's PTSS have been reported.ObjectivesWe sought to investigate the medical treatment factors associated with children's PTSS after PICU discharge.MethodsA prospective longitudinal cohort study was conducted in two Australian tertiary referral PICUs. Children aged 2-16 y admitted to the PICU between June 2008 and January 2011 for >8 h and <28 d were eligible for participation. Biometric and clinical data were obtained from medical records. Parents reported their child's PTSS using the Trauma Symptom Checklist for Young Children at 1, 3, 6, and 12 months after discharge. Logistic regression was used to assess potential associations between medical treatment and PTSS.ResultsA total of 265 children and their parents participated in the study. In the 12-month period following PICU discharge, 24% of children exhibited clinically elevated PTSS. Median risk of death (Paediatric Index of Mortality 2 [PIM2]) score was significantly higher in the PTSS group (0.31 [IQR 0.14–1.09] v 0.67 [IQR 0.20–1.18]; p = 0.014). Intubation and PICU and hospital length of stay were also significantly associated with PTSS at 1 month, as were midazolam, propofol, and morphine. After controlling for gender, reason for admission, and PIM2 score, only midazolam was significantly and independently associated with PTSS and only at 1 month (adjusted odds ration (aOR) 3.63, 95% CI 1.18, 11.12, p = 0.024). No significant relationship was observed between the use of medications and PTSS after 1 month.ConclusionsElevated PTSS were evident in one quarter (24%) of children during the 12 months after PICU discharge. One month after discharge, elevated PTSS were most likely to occur in children who had received midazolam therapy. 相似文献
10.
《Ultrasound in medicine & biology》2015,41(10):2562-2566
The primary aim of this study was to evaluate the accuracy of sonographic estimation of fetal weight when performed at due date by first-line sonographers. This was a prospective study including 500 singleton pregnancies. Ultrasound examinations were performed by residents on delivery day. Estimated fetal weights (EFWs) were calculated and compared with the corresponding birth weights. The median absolute difference between EFW and birth weight was 200 g (100–330). This difference was within ±10% in 75.2% of the cases. The median absolute percentage error was 5.53% (2.70%–10.03%). Linear regression analysis revealed a good correlation between EFW and birth weight (r = 0.79, p < 0.0001). According to Bland–Altman analysis, bias was −85.06 g (95% limits of agreement: −663.33 to 494.21). In conclusion, EFWs calculated by residents were as accurate as those calculated by experienced sonographers. Nevertheless, predictive performance remains limited, with a low sensitivity in the diagnosis of macrosomia. 相似文献