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51.
52.
Excessive daytime sleepiness (EDS) is a common but underrecognized and preventable cause of traffic accidents. It creates a problem of particular importance for professional drivers. We performed the Epworth Sleepiness Scale (ESS) and questionnaire related to their history of traffic accidents to 118 professional taxi drivers to determine the EDS and its effects on driving performance in taxi drivers. There were 58 (49.2%) subjects with loud snoring, 8 (5.9%) subjects with cardinal symptoms due to obstructive sleep apnea syndrome (OSAS) and 28 (23.7%) subjects with ESS > or =10 in the group of taxi drivers. Eighty (67.8%) drivers had been involved in a traffic accident. We found a significant relation between the number of traffic accident and EDS, witnessed apnea, cardinal symptom related to OSAS but not with snoring. The present data that sleepiness is a common symptom in taxi drivers and may be related to traffic accident.  相似文献   
53.
The construct of working memory and its reliance on dorsolateral prefrontal cortex (DLPFC) have been the focus of many studies in healthy subjects and in clinical populations. However, transfer of knowledge gained from cognitive science studies to clinical applications can be a challenging goal. This scarce cross-dissemination may be partially due to the use of ‘tools’ that are limited in their ability to generate meaningful information about impairments in clinical groups. To this end, this paper investigates the use of functional near-infrared spectroscopy (fNIRS), which offers unique opportunities for recording neuroactivation. Specifically, we examine measures of the DLPFC hemodynamic response during a working memory task in adults with traumatic brain injury (TBI) and healthy controls. Analysis of hemodynamic measures showed significant differences between the two groups, even without differences in behavioral performance. Additional subtle disparities were linked to levels of performance in TBI and healthy subjects. fNIRS hemodynamic measures may therefore provide novel information to existing theories and knowledge of the working memory construct. Future studies may further define these subtle differences captured by fNIRS to help identify which components affect inter-individual variations in performance and could play a contributing role in the choice and planning of neurorehabilitation interventions targeting working memory.  相似文献   
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55.
The aim of the study was to investigate the functional performance in children with spina bifida, using the Pediatric Evaluation of Disability Inventory(PEDI) to look into capacity of twenty-eight children with spina bifida with lesions at different levels in different dimensions of selfcare, mobility and social function. Mean age of the patients was 3.5 ± 2.3(1–10) years. In the muscle test carried out, 13 patients(44.8%) had no movements including pelvic elevation in lower extremity muscles and they were at level 5. Sixteen patients(54%) were non-ambulatory according to the Hoofer ambulation classification. Raw and scale scores in the self-care, mobility and social function domains both in the functional skill scale and in the caregiver scale were found to be lower compared to the data of the normal population. A statistically significant correlation was observed in the self-care values of the Functional Skills Scales and the Caregiver Assistance Scale measurements, which was positive for age and negative for Functional Ambulation Scale and muscle test(P 0.05). A positive relation was found between the Functional Skills Scales-mobility area and age while a negative relation was observed between Functional Ambulation Scale and muscle test(P 0.005). A negative relation was also found between Caregiver Assistance Scale-mobility and Functional Ambulation Scale and muscle test(P 0.005). In our study, the functional performance of the children was found to be low. Low-level lesions, encouraging muscular strength and independence in mobility are all very important factors for functional independence.  相似文献   
56.
Endometriosis is characterized by the growth of endometrium outside the uterine cavity or myometrium. There is no specific radiologic finding that defines endometriosis. Parenchymal lesions, nodules or blebs are reported in the literature, although this clinical entity is rare. Definitive diagnosis and treatment are often possible with surgery. We report here two cases: a forty-two-year-old female patient with a 2-year history of intermittent hemoptysis associated with her menstrual cycle was diagnosed as having endometriosis and treated via thoracotomy; another 30-year-old female referred to our department due to recurrent pneumothorax caused by underlying endometriosis underwent surgical treatment which revealed endometrial foci on the diaphragm.  相似文献   
57.
To determine the relationship between serum leptin levels and disease activity in systemic sclerosis (SSc). A total of 60 subjects (30 controls and 30 patients) were included. The inflammatory markers and leptin levels were evaluated and body mass index (BMI) was measured for both groups. The assessment of the skin involvement was performed based on the modified Rodnan skin score (mRSS). Disease activity was evaluated according to the Valentini scleroderma disease activity index. There was a significant difference between the patient and control groups in terms of BMI (p?<?0.05); however there was no difference with regards to age and gender (p?>?0.05). Valentini scores and mRSS were determined to be significantly higher in active patients (n?=?14) than in inactive patients (n?=?16) (p?<?0.05). No significant difference was determined between groups in terms of leptin levels (p?>?0.05). However, leptin levels were significantly lower in active patients than in inactive patients (p?<?0.05). We found a significant positive correlation between serum leptin and BMI (p?<?0.05), and leptin and serum C3 levels (p?<?0.05); no relationship was detected between leptin and other parameters. Leptin can be used as an activity marker in SSc. Further studies, including larger series, should be carried out to clarify this relationship.  相似文献   
58.
Glioblastomas (GBMs) diffusely infiltrate the brain, making complete removal by surgical resection impossible. The mixture of neoplastic and nonneoplastic cells that remain after surgery form the biological context for adjuvant therapeutic intervention and recurrence. We performed RNA-sequencing (RNA-seq) and histological analysis on radiographically guided biopsies taken from different regions of GBM and showed that the tissue contained within the contrast-enhancing (CE) core of tumors have different cellular and molecular compositions compared with tissue from the nonenhancing (NE) margins of tumors. Comparisons with the The Cancer Genome Atlas dataset showed that the samples from CE regions resembled the proneural, classical, or mesenchymal subtypes of GBM, whereas the samples from the NE regions predominantly resembled the neural subtype. Computational deconvolution of the RNA-seq data revealed that contributions from nonneoplastic brain cells significantly influence the expression pattern in the NE samples. Gene ontology analysis showed that the cell type-specific expression patterns were functionally distinct and highly enriched in genes associated with the corresponding cell phenotypes. Comparing the RNA-seq data from the GBM samples to that of nonneoplastic brain revealed that the differentially expressed genes are distributed across multiple cell types. Notably, the patterns of cell type-specific alterations varied between the different GBM subtypes: the NE regions of proneural tumors were enriched in oligodendrocyte progenitor genes, whereas the NE regions of mesenchymal GBM were enriched in astrocytic and microglial genes. These subtype-specific patterns provide new insights into molecular and cellular composition of the infiltrative margins of GBM.Glioma cells diffusely infiltrate the brain and intermingle with neural cells in the surrounding brain tissue, resulting in a complex mixture that includes variable proportions of glioma cells, neurons, and various lineages of reactive or recruited glia. At the infiltrative margins of glioblastoma (GBM), the nonneoplastic brain cells can far outnumber the glioma cells and, therefore, will have a significant effect on the molecular features of the tissue. Expression profiling and whole genome sequencing from hundreds of GBM specimens by The Cancer Genome Atlas (TCGA) has revealed a broad spectrum of genetic alterations and discrete expression signatures or subtypes that stratify the majority of patients (1, 2). These studies analyzed tumor samples that were removed during surgery, but were not radiographically localized and, therefore, do not address the question of how the molecular signature may vary across different regions of a tumor. Recent studies have sampled multiple regions within a GBM and shown that more than one molecular subtype can coexist within a single tumor (3). However, the effect of varying cellular composition on GBM subtype, particularly the contribution of nonneoplastic cells, has not been addressed.GBM typically appears as a contrast-enhancing mass, which represents the highly cellular core of the tumor with vascular proliferation and blood–brain barrier breakdown. This contrast-enhancing (CE) region is typically surrounded by a diffuse, nonenhancing (NE) region of abnormal T2/FLAIR signal, which represents edematous brain tissue with varying numbers of infiltrating glioma cells. The primary treatment of GBM is surgical resection, during which the surgeon removes as much of the CE mass as possible. Thus, molecular and genetic profiling of GBM, including the TCGA effort, has predominantly used samples from the CE regions of tumor. However, it is the NE regions of glioma that are left behind after surgery, which neurooncologists must treat and which inevitably give rise to recurrence. Thus, there is immense prognostic and therapeutic significance to understanding the cellular and molecular features of the NE regions of tumor, yet often these areas are not resected and, therefore, have not been directly studied.There are two major obstacles to this goal. The first is the surgical challenge of radiographically localized sampling of the NE tumor margins. The second is the issue of the complex cellular composition that characterizes these regions of diffuse infiltration. In this study, we have addressed both challenges, and associated distinct molecular and cellular features of the NE regions of GBM with the molecular subtype, as defined by the resected CE regions of the tumor.  相似文献   
59.

Objective

To explore the role of a community-based intervention in reducing delays in accessing emergency obstetric care (EmOC) in rural Bangladesh, and the factors associated with delayed decision making, reaching the health facility and receiving treatment.

Study design

Quasi-experimental study.

Methods

Multistage random sampling was used to select 540 villages, from which 1200 women who reported obstetric complications in March–April 2010 were interviewed.

Results

The median time taken to make the decision to access health care was significantly lower in the intervention areas compared with the control areas (80 vs 90 min). In addition, the median time taken to reach the health facility was significantly lower in the intervention areas compared with the control areas (110 vs 135 min). However, no difference was found in the median time taken to receive treatment. Multiple linear regressions demonstrated that the community intervention significantly reduced decision making and time taken to reach the health facility when accessing EmOC in rural Bangladesh. However, for women experiencing haemorrhage, the delays were longer in the intervention areas. Protective factors against delayed decision making included access to television, previous medical exposure, knowledge, life-threatening complications during childbirth and use of a primary health facility. Financial constraints and traditional perceptions were associated with delayed decision making. Complications during labour, use of a motorized vehicle and use of a primary health facility were associated with faster access to EmOC, and poverty, distance, transportation difficulties and decision made by male guardian were associated with slower access to EmOC.

Conclusions

The intervention appeared to reduce the time taken to make the decision to access health care and the time taken to reach the health facility when accessing EmOC. This study provides support for a focus on emergency preparedness for timely referral from the community.  相似文献   
60.
Risk prediction models play an important role in prevention and treatment of several diseases. Models that are in clinical use are often refined and improved. In many instances, the most efficient way to improve a successful model is to identify subgroups for which there is a specific biological rationale for improvement and tailor the improved model to individuals in these subgroups, an approach especially in line with personalized medicine. At present, we lack statistical tools to evaluate improvements targeted to specific subgroups. Here, we propose simple tools to fill this gap. First, we extend a recently proposed measure, the Integrated Discrimination Improvement, using a linear model with covariates representing the subgroups. Next, we develop graphical and numerical tools that compare reclassification of two models, focusing only on those subjects for whom the two models reclassify differently. We apply these approaches to BRCAPRO, a genetic risk prediction model for breast and ovarian cancer, using data from MD Anderson Cancer Center. We also conduct a simulation study to investigate properties of the new reclassification measure and compare it with currently used measures. Our results show that the proposed tools can successfully uncover subgroup specific model improvements. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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