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21.
22.
BACKGROUND: Executive deficits associated with frontal lobe dysfunction are prominent in depression. We applied a newly developed WM task to investigate the neural correlates of executive processes with functional magnetic resonance imaging (fMRI) at comparable performance levels analyzing correct trials only. METHODS: We studied 12 partially remitted, medicated inpatients meeting DSM-IV criteria for major depressive disorder and 17 healthy controls. We used a parametric version of a delayed match-to-sample WM task requiring manipulation of verbal material during a delay period in an event-related fMRI design. RESULTS: Depressed patients were generally slower and load-dependently less accurate than healthy controls. Patients showed significantly more activation of left dorsolateral prefrontal cortex with highest cognitive load. Additionally, they showed higher activation in ventromedial prefrontal cortex during the control condition. LIMITATIONS: The fact that patients were taking different antidepressant drugs could limit the explanatory power of the present results. CONCLUSIONS: Increased lateral prefrontal activation despite comparably successful performance - when only correct trials were analyzed - in patients with depression can be interpreted as evidence for compensatory recruitment of prefrontal cortical resources.  相似文献   
23.
In order to investigate new potential therapeutically active agents, we investigated the biological properties of two small libraries of quinoxalinones and 1,4‐benzoxazin‐2‐ones. The results obtained showed that compounds 5 , 9–11 have good cytotoxic activity against HeLa cells where the lowest IC50 value (10.46 ± 0.82 μM/mL) was measured for compound 10 . Additionally, the most active compounds ( 5 , 9 – 11 ) showed much better selectivity for MRC‐5 cells (up to 17.4) compared to cisplatin. In vitro evaluation of the inhibition of the enzyme α‐glucosidase showed that compounds 10 and 11 exert significant inhibition of the enzyme at 52.54 ± 0.09 and 40.09 ± 0.49 μM, respectively. Competitive experiments with ethidium bromide (EB) indicated that all tested compounds have affinity to displace EB from the EB‐DNA complex through intercalation, suggesting good competition with EB (Ksv = (3.1 ± 0.2), (5.1 ± 0.1), (5.6 ± 0.2), and (6.3 ± 0.2) × 103 M?1). A molecular docking study was also performed to better understand the binding modes and to conclude the structure–activity relationships of the synthesized compounds.
  相似文献   
24.
Turton AJ  McCabe CS  Harris N  Filipovic SR 《Pain》2007,127(3):270-275
There is evidence that patients with Complex Regional Pain Syndrome (CRPS) have altered central sensorimotor processing. Sensory input can influence motor output either through indirect pathways or through direct connections from the sensory to motor cortex. The purpose of this study was to investigate sensorimotor interaction via direct connections in patients with CRPS and to compare the results with normal subjects'. Direct short-latency sensory-motor interaction was evaluated in eight patients with CRPS1 affecting a hand. Modulation of EMG responses to transcranial magnetic stimulation (TMS) induced by concomitant median nerve stimulation was measured, the so-called, short-latency afferent inhibition (SAI). Results were compared with eight normal subjects who were age and sex matched with the patients. As expected, all the normal subjects' EMG responses to TMS with median nerve stimulation were smaller than responses to TMS alone. In seven of the eight CRPS patients EMG responses to TMS were suppressed when paired with median nerve stimulation. Only one CRPS patient's results showed no suppression of EMG responses. These results suggest that the disease mechanisms of CRPS1 do not typically affect the direct neural circuit between sensory and motor cortex and that normal sensorimotor interaction is occurring via this route.  相似文献   
25.

Background

Ineffective esophageal motility (IEM) in patients with gastroesophageal reflux disease includes three different subsets that may affect symptom profiles. Our aim was to assess symptoms and functional outcome in patients with erosive esophagitis according to different subsets of IEM, before and after Nissen fundoplication (NF).

Methodology

A retrospective study with prospective follow-up of 72 patients with reflux esophagitis and IEM in whom open NF was performed. Based on principal manometric esophageal body motility disorder, patients were divided in three groups: predominantly low-amplitude (LAC, N?=?38), non-propulsive (NPC, N?=?18), and simultaneous low-amplitude esophageal contractions (SC, N?=?16). Patients underwent symptomatic questionnaire and stationary esophageal manometry before and 6 months, 1 year, and 3 years after surgery.

Results

Preoperatively, patients in NPC and SC groups had higher mean scores of dysphagia, without statistical significance as opposed to the LAC group (p?=?0.239). Postoperative dysphagia occurred in 36 patients, without statistical significance between groups regarding dysphagia grades (p?=?0.390). A longer duration of postoperative dysphagia was noted in the SC group (p?p?Conclusion Three years after NF, successful symptomatic and functional outcome was achieved in analyzed groups of patients with erosive esophagitis regardless of IEM subtype.  相似文献   
26.
In this paper, the influence of the variation in transformer oil temperature on the accuracy of the all-acoustic non-iterative method for partial discharge location in a power transformer is researched. The research can improve power transformers’ testing and monitoring, particularly given the large transformer oil temperature variations during real-time monitoring. The research is based on quantifying the contribution of oil temperature to the standard combined measurement uncertainty of the non-iterative algorithm by using analytical, statistical, and Monte Carlo methods. The contribution can be quantified and controlled. The contribution varied significantly with different mutual placements of partial discharge and acoustic sensors. The correlation between the contribution and the mean distance between partial discharge and acoustic sensors was observed. Based on these findings, the procedure to quantify and control the contribution in practice was proposed. The procedure considers the specificity of the method’s mathematical model (the assumption that the oil temperature is constant), the non-iterative algorithm’s nonlinearity, and the large variations in transformer oil temperature. Existing studies did not consider the significant effect of the oil temperature on the combined measurement uncertainty of partial discharge location influenced by those phenomena. The research is limited to partial discharge located in the transformer oil.  相似文献   
27.
The surgeon's ability to recognize abnormal vascular anatomy has greater importance than ever in modern esophagogastric surgical procedures. Some aberrations of vascular vessels around the stomach found during extensive surgery due to primary cancer of the stomach, cardia and lower esophagus are presented in this paper. The purpose of the prospective study is to evaluate and classify these variations with respect to their impact in visceral surgery. A total of 426 patients who underwent total or extensive gastrectomy and esophagectomy combined with lymphadenectomy, have been analyzed prospectively. For the period of 10 years some vascular aberrations have been found in 54/426 (12.67%) of the patients in the operative field during lymphadenectomy as single or combined anomalies. An arterial perigastric anatomy considered normal in textbooks was found in 372 (87.32%) cases. An accessory left hepatic artery arising from the left gastric artery was found in 19/54 (35.18%), and replaced type in 7/54 (12.96%). The replaced right hepatic artery branching from the superior mesenteric artery was found in 5/54 (7.40%) cases. Replaced and accessory left gastric artery branching from the aorta was found in 8/54 (14.8%); accessory posterior gastric artery was found in 25/54 (44.4%), and abnormalities of the splenic, and subphrenic arteries were found in 6/54 (11.11%). Combined anomalies of both left and right hepatic arteries and variations of the celiac trunk were found in 2/54 (3.70%) cases. Forty-nine cases were classified according to established Michels' typology system. Six cases presented with extremely rare variations and remain unclassified. Possible intraoperative problems concerning postoperative complications are also emphasized.  相似文献   
28.
The aim of this study was to define features of Guillain‐Barré syndrome in a large cohort of patients from three Western Balkans countries. Data from adult Guillain‐Barré syndrome (GBS) cases from 2009 to 2013 were retrospectively obtained from all tertiary health care centers. During the 5‐year period, 327 new cases of GBS were identified with a male to female ratio of 1.7 : 1. The most common GBS variants were demyelinating (65%) and axonal (12%). At nadir 45% of patients were chair‐bound, confined to bed, or required assisted ventilation, while 5% died. The crude incidence of GBS in Serbia and Montenegro was 0.93 per 100,000 population, and age‐adjusted incidence according to the world standard population was 0.86 per 100,000. Incidence was particularly high in 50‐ to 80‐year‐old men. Statistically significant seasonal variations of GBS were not observed. This study of patients with GBS in the Western Balkans allows us to prepare the health system better and to improve the management of patients. This study also opens opportunities for international collaboration and for taking part in the multinational studies on GBS.  相似文献   
29.

Purpose

The Patient Reported Outcomes Measurement Information System (PROMIS ® ) is a US National Institutes of Health initiative that has produced self-report outcome measures, using a framework of physical, mental, and social health defined by the World Health Organization in 1948 (WHO, in Preamble to the Constitution of the World Health Organization as adopted by the International Health Conference, New York, 1948). The World Health Organization’s International Classification of Functioning, Disability and Health (ICF) is a comprehensive classification system of health and health-related domains that was put forward in 2001. The purpose of this report is to compare and contrast PROMIS and ICF conceptual frameworks to support mapping of PROMIS instruments to the ICF classification system .

Methods

We assessed the objectives and the classification schema of the PROMIS and ICF frameworks, followed by content analysis to determine whether PROMIS domain and sub-domain level health concepts can be linked to the ICF classification.

Results

Both PROMIS and ICF are relevant to all individuals, irrespective of the presence of health conditions, person characteristics, or environmental factors in which persons live. PROMIS measures are intended to assess a person’s experiences of his or her health, functional status, and well-being in multiple domains across physical, mental, and social dimensions. The ICF comprehensively describes human functioning from a biological, individual, and social perspective. The ICF supports classification of health and health-related states such as functioning, but is not a specific measure or assessment of health, per se. PROMIS domains and sub-domain concepts can be meaningfully mapped to ICF concepts.

Conclusions

Theoretical and conceptual similarities support the use of PROMIS instruments to operationalize self-reported measurement for many body function, activity and participation ICF concepts, as well as several environmental factor concepts. Differences observed in PROMIS and ICF conceptual frameworks provide a stimulus for future research and development.  相似文献   
30.
Novel Pd(II) complex with N‐heteroaromatic Schiff base ligand, derived from 8‐quinolinecarboxaldehyde (q8a) and ethyl hydrazinoacetate (haOEt), was synthesized and characterized by analytical and spectroscopy methods. The structure of novel complex, as well as structures of its quinoline and pyridine analogues, was optimized by density functional theory calculations, and theoretical data show good agreement with experimental results. A cytotoxic action of the complexes was evaluated on cultures of human promyelocytic leukemia (HL‐60), human glioma (U251), rat glioma (C6), and mouse fibrosarcoma (L929) cell lines. Among investigated compounds, only complexes with quinoline‐based ligands reduce the cell numbers in a dose‐dependent manner in investigated cell lines. The observed cytotoxic effect of two isomeric quinoline‐based complexes is predominantly mediated through the induction of apoptotic cell death in HL‐60 cell line. The cytotoxicity of most efficient novel Pd(II) complex is comparable to the activity of cisplatin, in all cell lines investigated.  相似文献   
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