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   5641篇
  免费   267篇
  国内免费   58篇
耳鼻咽喉   64篇
儿科学   75篇
妇产科学   143篇
基础医学   422篇
口腔科学   179篇
临床医学   378篇
内科学   1440篇
皮肤病学   185篇
神经病学   518篇
特种医学   228篇
外科学   916篇
综合类   36篇
预防医学   326篇
眼科学   169篇
药学   272篇
中国医学   6篇
肿瘤学   609篇
  2024年   5篇
  2023年   38篇
  2022年   97篇
  2021年   142篇
  2020年   95篇
  2019年   107篇
  2018年   151篇
  2017年   104篇
  2016年   151篇
  2015年   163篇
  2014年   246篇
  2013年   302篇
  2012年   444篇
  2011年   516篇
  2010年   279篇
  2009年   264篇
  2008年   460篇
  2007年   461篇
  2006年   408篇
  2005年   394篇
  2004年   331篇
  2003年   283篇
  2002年   231篇
  2001年   35篇
  2000年   25篇
  1999年   40篇
  1998年   43篇
  1997年   27篇
  1996年   23篇
  1995年   11篇
  1994年   13篇
  1993年   3篇
  1992年   11篇
  1991年   3篇
  1990年   2篇
  1989年   2篇
  1988年   7篇
  1987年   4篇
  1985年   2篇
  1984年   4篇
  1982年   4篇
  1981年   4篇
  1980年   8篇
  1979年   5篇
  1978年   3篇
  1977年   2篇
  1976年   2篇
  1975年   2篇
  1974年   3篇
  1963年   1篇
排序方式: 共有5966条查询结果,搜索用时 15 毫秒
101.
102.

Aim-Background

Ambulatory surgery has become the standard method of care for elective operations in many countries. Nevertheless, day surgery in Greece is far from being established as the modality of choice when performing specific operations. The aim of this study was to evaluate the safety and feasibility of day case surgery in selected operations, as well as patient satisfaction.

Methods

Patients were selected last year over a period of twelve months to undergo operations in the setting of ambulatory surgery. Selection criteria were related to social and medical factors; among others, these included the presence of an accompanying adult, elective surgery, and age under 75 years. We performed 142 operations including laparoscopic cholecystectomies, hernia repair and treatment of perianal diseases. Anaesthetic methods comprised general anaesthesia, local anaesthesia and Transversus Abdominis Plane (TAP) block.

Results

No major complications were recorded for any of the selected surgeries, nor any readmissions. The average cost for the total amount of surgeries was reduced by 40%. This cost reduction was mainly due to the limited use of abdominal drains, restricted preoperative examinations and strict anaesthetic protocol. All patients declared satisfaction with the treatment modality that was offered to them.

Conclusions

Following careful and methodic patient selection, day case surgery can reduce the cost of hospitalization and provide patient satisfaction, in addition to being both achievable and safe.  相似文献   
103.
The aim of this in vitro study was to evaluate the performance of various contemporary detection tools at incipient occlusal caries. Thirty eight freshly extracted posterior teeth with non-cavitated occlusal caries were subjected to clinical examination and coding according to ICDAS criteria (n?=?38). Standardized fluorescence images were taken with VistaProof (Dürr Dental, Bietigheim-Bissingen, Germany). Furthermore, the teeth were calculated with a laser fluorescence pen device (DIAGNOdent pen, Kavo, Biberach, Germany). In all detection methods, assessment of caries was performed twice (with 1-week interval) by two calibrated examiners. Finally, the caries lesions were validated in tooth sections by histological examination. The intra-examiner and inter-examiner kappa coefficient, sensitivity, and specificity were determined for all detection methods at enamel lesions (D1 threshold). Degrees of agreement of each method with the histological status were calculated using receiver operating characteristic statistics and the area under curve (Az values). The kappa intra-examiner/inter-examiner coefficient values (mean?±?SD) were 0.74?±?0.04/0.73?±?0.07, 0.87?±?0.04/0.82?±?0.07, and 0.91?±?0.06/0.83?±?0.08 for clinical examination, DIAGNOdent pen, and VistaProof, respectively. The sensitivity for ICDAS was 0.80–0.86, for DIAGNOdent pen was 0.66–0.75, and for the VistaProof device was 0.97. The specificity for all the detection methods were 0.5 (0.02–0.99). The accuracy value for ICDAS was 0.76–0.81, for DIAGNOdent pen 0.66–0.71, and for the VistaProof device 0.92–0.95. The Az values (mean?±?SD) were 0.431?±?0.187, 0.583?±?0.215, and 0.486?±?0.207 for ICDAS, DIAGNOdent pen, and VistaProof examination, respectively. No significant differences in Az values were noted among the methods. All detection methods were presented with high inter-examiner and intra-examiner agreement. The new VistaProof device showed the best sensitivity, while DIAGNOdent pen demonstrated the worst one. Specificities were the same for all detection methods. Moreover, they presented the same performance in detection of incipient occlusal caries.  相似文献   
104.
105.
Chronic bronchitis (CB) is an indicator of an increased risk of developing COPD, but its symptoms are often underestimated. Demographic and socio-economic conditions might influence its prevalence, reporting and impact. Data from a large epidemiological survey of the French general population were analyzed to determine the burden of CB, the magnitude of under-diagnosis and the influence of age, gender and socio-economic conditions. Altogether, 9050 participants aged 45 years or more provided complete data. The prevalence of symptoms and diagnosis of CB was 3.5% and 3.4%, respectively. CB was associated with impaired health status and activity and, in women, work loss. Among subjects with symptoms of CB, only 28.6% declared a known diagnosis of respiratory disease. Factors associated with symptoms of CB in multivariate analysis were male gender, active smoking, lower income and occupational category: the highest prevalence was observed in manual workers (5.6%) and self-employed subjects (5.2%). The under-diagnosis of CB was more marked in men and subjects of higher socio-economic categories. These results confirm that CB is markedly under-diagnosed in the general population. Socio-economic conditions influence both its prevalence (higher in low categories) and rate of diagnosis (lower in high categories), which should be considered when elaborating prevention and detection campaigns.  相似文献   
106.
The isolation of the aneurysm sac from systemic pressure and its consequent shrinkage are considered criteria of success after endovascular repair (EVAR). However, the process of shrinkage does not solely depend on the intrasac pressure, the predictive role of which remains ambiguous. This brief review summarizes the additional pathophysiological mechanisms that regulate the biomechanical properties of the aneurysm wall and may interfere with the process of aneurysm sac shrinkage.  相似文献   
107.
108.
109.

Zusammenfassung

Hintergrund: Die Auswirkungen einer Schwangerschaft auf die Prognose des Mammakarzinoms werden in der Literatur kontrovers diskutiert. Wir haben eine gepaarte Fall-Fall-Studie konzipiert, in der schwangerschaftsasso-ziierte Mammakarzinom (SAM)-Fälle entsprechend ihres Stadiums, Alters und Jahr der Diagnosestellung mit Mammakarzinom-Patientinnen gepaart wurden. Patientinnen und Methoden: 39 aufeinanderfolgende SAM-Fälle wurden mit 39 prämenopausalen Fällen von Brust-krebs gepaart. Univariate und multivariate Überlebens-analysen mit Anpassung an Stadium, Grad, Östrogen-rezeptorstatus und Alter zum Zeitpunkt der Diagnose wurden durchgeführt. Ergebnisse: Hinsichtlich des Gesamtüberlebens deutete die univariate Analyse auf ein längeres Gesamtüberleben für nicht-SAM-Fälle vs. SAM-Fälle hin. Gleichzeitig war ein fortgeschritteneres Stadium ein Prädiktor für ein kürzeres Überleben. Die multivariate Analyse bestätigte die unabhängige ver-schlechternde Auswirkung einer Schwangerschaft. Inter-essanterweise ergab eine genestete Post-hoc-Analyse der SAM-Fälle Hinweise auf ein kürzeres Gesamtüberleben für das dritte Trimester. Die oben erwähnten Ergebnisse für das Gesamtüberleben konnten desweiteren bei der Untersuchung des rezidivfreien Überlebens reproduziert werden. Schlussfolgerung: Mit ihrem gepaarten Fall-Fall-Design deutet die vorliegende Studie darauf hin, dass Schwangerschaft ein schlechter Prognosefaktor beim Mammakarzinom ist.  相似文献   
110.
We report a British family with young-onset Parkinson’s disease (PD) and a G51D SNCA mutation that segregates with the disease. Family history was consistent with autosomal dominant inheritance as both the father and sister of the proband developed levodopa-responsive parkinsonism with onset in their late thirties. Clinical features show similarity to those seen in families with SNCA triplication and to cases of A53T SNCA mutation. Post-mortem brain examination of the proband revealed atrophy affecting frontal and temporal lobes in addition to the caudate, putamen, globus pallidus and amygdala. There was severe loss of pigmentation in the substantia nigra and pallor of the locus coeruleus. Neuronal loss was most marked in frontal and temporal cortices, hippocampal CA2/3 subregions, substantia nigra, locus coeruleus and dorsal motor nucleus of the vagus. The cellular pathology included widespread and frequent neuronal α-synuclein immunoreactive inclusions of variable morphology and oligodendroglial inclusions similar to the glial cytoplasmic inclusions of multiple system atrophy (MSA). Both inclusion types were ubiquitin and p62 positive and were labelled with phosphorylation-dependent anti-α-synuclein antibodies In addition, TDP-43 immunoreactive inclusions were observed in limbic regions and in the striatum. Together the data show clinical and neuropathological similarities to both the A53T SNCA mutation and multiplication cases. The cellular neuropathological features of this case share some characteristics of both PD and MSA with additional unique striatal and neocortical pathology. Greater understanding of the disease mechanism underlying the G51D mutation could aid in understanding of α-synuclein biology and its impact on disease phenotype.  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