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991.
OBJECTIVE: Several studies have reported the association of systemic sclerosis (SSc) with thyroid autoimmune disorders, but most of them have neither an appropriate control group nor include a complete thyroid work-up. DESIGN: The aim of our study was to evaluate the prevalence of thyroid disorders in a large number of patients with SSc using a complete clinical evaluation. METHODS: Thyroid-stimulating hormone (TSH), free triiodothyronine, free thyroxine, antithyroglobulin and antithyroid-peroxidase (AbTPO) autoantibodies, thyroid ultrasonography and blood flow and fine needle aspiration were performed in 202 SSc patients versus 404 gender- and age-matched controls from the general population, with similar iodine intake, to evaluate the prevalence of clinical and subclinical thyroid disorders. RESULTS: Odds ratio (OR) for female SSc versus controls was: for subclinical hypothyroidism, 3.2 (95% CI)=1.8-5.7); for clinical hypothyroidism, 14.5 (95% CI=2.3-90.9); for AbTPO positivity, 2.7 (95% CI=1.8-4.1); for hypoechoic pattern, 3.2 (95% CI=2.2-4.7); for thyroid autoimmunity, 3.7 (95% CI=2.6-5.4); for thyroid volume <6 ml, 1.8 (95% CI=1.2-2.7). OR for thyroid autoimmunity in male SSc versus controls was 10.8 (95% CI=2.2-52.4). Mean values of TSH in female SSc, and of AbTPO in female and male SSc were higher (P<0.01) than in controls. We observed three cases of Graves' disease in female SSc versus zero in controls (P=0.0140), and two cases of papillary thyroid cancer in SSc patients. CONCLUSIONS: Thyroid function, AbTPO and ultrasonography should be tested as part of the clinical profile in SSc patients. Females, subjects with positive AbTPO and hypoechoic and small thyroid should have thyroid function follow-up and appropriate treatment in due course.  相似文献   
992.
993.
Healthy human colon samples were analyzed ex vivo with a multispectral imaging Mueller polarimeter operating from 500 to 700 nm in a backscattering configuration with diffuse light illumination impinging on the innermost tissue layer, the mucosa. The intensity and polarimetric responses were taken on whole tissues first and after progressive exfoliation of the outer layers afterwards. Moreover, these measurements were carried out with two different substrates (one bright and the other dark) successively placed beneath each sample, allowing a reasonably accurate evaluation of the contributions to the overall backscattered light by the various layers. For the shorter investigated wavelengths (500 to 550 nm) the major contribution comes from mucosa and submucosa, while for the longer wavelengths (650 to 700 nm) muscular tissue and fat also contribute significantly. The depolarization has also been studied and is found to be stronger in the red part of the spectrum, mainly due to the highly depolarizing power of the muscular and fat layers.  相似文献   
994.
To characterize respiratory virus infections during the first autumn-winter season of pandemic A (H1N1) 2009 influenza virus (A/H1N1/2009) circulation, a prospective study in children attending a paediatric emergency department at the Sapienza University hospital, Rome, was conducted from November 2009 to March 2010. By means of both nasal washings and pharyngeal swabs, enrolled children were checked for 14 respiratory viruses. The majority of acute respiratory infections resulted from viral pathogens (135/231, 58%). Overall, the most common was respiratory syncytial virus (RSV), in 64% of positive samples; A/H1N1/2009 was the only influenza virus found in 16% and rhinovirus (RV) in 15%. Virus-positive children did not differ significantly from virus-negative children in signs and symptoms at presentation; of the virus groups, RSV-infected children were younger and more frequently admitted to intensive-care units than those infected with A/H1N1/2009 and RV. Of the hospitalized children, stratified by age, both infants and children aged >1 year with RSV were most severely affected, whereas A/H1N1/2009 infections were the mildest overall, although with related pulmonary involvement in older children. Children with RV infections, detected in two flares partially overlapping with the A/H1N1/2009 and RSV peaks, presented with bronchiolitis, wheezing and pneumonia. Leukocytosis occurred more frequently in RV-infected and A/H1N1/2009-infected children, and numbers of blood eosinophils were significantly elevated in RV-infected infants. Given the fact that clinical and epidemiological criteria are not sufficient to identify viral respiratory infections, a timely virological diagnosis could allow different infections to be managed separately.  相似文献   
995.
996.
997.

Purpose

Our objective was to revise the definition of acute respiratory distress syndrome (ARDS) using a conceptual model incorporating reliability and validity, and a novel iterative approach with formal evaluation of the definition.

Methods

The European Society of Intensive Care Medicine identified three chairs with broad expertise in ARDS who selected the participants and created the agenda. After 2?days of consensus discussions a draft definition was developed, which then underwent empiric evaluation followed by consensus revision.

Results

The Berlin Definition of ARDS maintains a link to prior definitions with diagnostic criteria of timing, chest imaging, origin of edema, and hypoxemia. Patients may have ARDS if the onset is within 1?week of a known clinical insult or new/worsening respiratory symptoms. For the bilateral opacities on chest radiograph criterion, a reference set of chest radiographs has been developed to enhance inter-observer reliability. The pulmonary artery wedge pressure criterion for hydrostatic edema was removed, and illustrative vignettes were created to guide judgments about the primary cause of respiratory failure. If no risk factor for ARDS is apparent, however, objective evaluation (e.g., echocardiography) is required to help rule out hydrostatic edema. A minimum level of positive end-expiratory pressure and mutually exclusive PaO2/FiO2 thresholds were chosen for the different levels of ARDS severity (mild, moderate, severe) to better categorize patients with different outcomes and potential responses to therapy.

Conclusions

This panel addressed some of the limitations of the prior ARDS definition by incorporating current data, physiologic concepts, and clinical trials results to develop the Berlin definition, which should facilitate case recognition and better match treatment options to severity in both research trials and clinical practice.  相似文献   
998.

Purpose

The recent increase in drug-resistant micro-organisms complicates the management of hospital-acquired bloodstream infections (HA-BSIs). We investigated the epidemiology of HA-BSI and evaluated the impact of drug resistance on outcomes of critically ill patients, controlling for patient characteristics and infection management.

Methods

A prospective, multicentre non-representative cohort study was conducted in 162 intensive care units (ICUs) in 24 countries.

Results

We included 1,156 patients [mean?±?standard deviation (SD) age, 59.5?±?17.7?years; 65?% males; mean?±?SD Simplified Acute Physiology Score (SAPS)?II score, 50?±?17] with HA-BSIs, of which 76?% were ICU-acquired. Median time to diagnosis was 14 [interquartile range (IQR), 7–26] days after hospital admission. Polymicrobial infections accounted for 12?% of cases. Among monomicrobial infections, 58.3?% were gram-negative, 32.8?% gram-positive, 7.8?% fungal and 1.2?% due to strict anaerobes. Overall, 629 (47.8?%) isolates were multidrug-resistant (MDR), including 270 (20.5?%) extensively resistant (XDR), and 5 (0.4?%) pan-drug-resistant (PDR). Micro-organism distribution and MDR occurrence varied significantly (p?<?0.001) by country. The 28-day all-cause fatality rate was 36?%. In the multivariable model including micro-organism, patient and centre variables, independent predictors of 28-day mortality included MDR isolate [odds ratio (OR), 1.49; 95?% confidence interval (95?%CI), 1.07–2.06], uncontrolled infection source (OR, 5.86; 95?%CI, 2.5–13.9) and timing to adequate treatment (before day?6 since blood culture collection versus never, OR, 0.38; 95?%CI, 0.23–0.63; since day?6 versus never, OR, 0.20; 95?%CI, 0.08–0.47).

Conclusions

MDR and XDR bacteria (especially gram-negative) are common in HA-BSIs in critically ill patients and are associated with increased 28-day mortality. Intensified efforts to prevent HA-BSIs and to optimize their management through adequate source control and antibiotic therapy are needed to improve outcomes.  相似文献   
999.
The genetic diversity of the host is believed to be the key of the diversity in the clinical presentation of bronchiolitis. The aim of this study was to determine whether the known rs12979860 and rs8099917 single nucleotide polymorphisms (SNPs) in interleukin (IL)28B region, influence clinical features and natural history of bronchiolitis. Both SNPs showed no significant association with the risk of hospitalization for respiratory syncytial virus (RSV), viral load, disease severity, and other clinical features of patients. Interestingly infants carrying IL28B rs12979860 TT genotype had lower age at hospital admission than that of infants carrying CC/CT genotypes. Overall our results indicate that both IL28B SNPs had no impact on the clinical course of bronchiolitis with the only exception of the IL28B rs12979860 SNP which increased the risk of hospitalization for bronchiolitis at early age.  相似文献   
1000.
Papillary tumor of the pineal region (PTPR) is a rare variety of CNS neoplasms and, since its first definition in 2003, only 64 cases have been described. PTPR is a primary neoplasm morphologically characterized by papillary structure staining for cytokeratin, transthyretin, neurone-specific enolase and S-100 protein. We report on a case of about 4 years' clinical history and neuroradiological follow-up of PTPR, in a 47-year-old Indian patient, with the aim of increasing the knowledge of its natural history. We describe through CT and MRI scans the natural evolution of this neoplasm, enhancing changes and morphologic structures involved, together with the final surgical treatment and pathological details. A mean growth rate average was calculated for this kind of lesion. In conclusion, the inexorable progressive growing nature of this tumor leads us to advocate an aggressive attitude among neurosurgeons and radiotherapists, with a precocious surgical approach when the suspicion rises.  相似文献   
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