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101.
Graspable objects grab attention when the potential for action is recognized   总被引:10,自引:0,他引:10  
Visually guided grasping movements require a rapid transformation of visual representations into object-specific motor programs. Here we report that graspable objects may facilitate these visuomotor transformations by automatically grabbing visual spatial attention. Human subjects viewed two task-irrelevant objects--one was a 'tool', the other a 'non-tool'--while waiting for a target to be presented in one of the two object locations. Using event-related potentials (ERPs), we found that spatial attention was systematically drawn to tools in the right and lower visual fields, the hemifields that are dominant for visuomotor processing. Using event-related fMRI, we confirmed that tools grabbed spatial attention only when they also activated dorsal regions of premotor and prefrontal cortices, regions associated with visually guided actions and their planning. Although it is widely accepted that visual sensory gain aids perception, our results suggest that it may also have consequences for object-directed actions.  相似文献   
102.
The usefulness of whole-body blood pool imaging as part of Tc-99m methylene diphosphonate (MDP) skeletal scintigraphy in detection of marrow infiltrative processes and unexpected soft-tissue and visceral abnormalities is demonstrated via illustrative case examples. Technical aspects of this simple and fast scanning technique are also highlighted.  相似文献   
103.

Background  

To perform a systematic review about the effect of using clinical pathways on length of stay (LOS), hospital costs and patient outcomes. To provide a framework for local healthcare organisations considering the effectiveness of clinical pathways as a patient management strategy.  相似文献   
104.
The electro-oculogram (EOG) is recorded by a personal computer and analyzed during the examination. If the results obtained with this method in normal subjects are compared with the conventional method (with which data recorded in analog form have to be measured manually), there is no significant difference. In patients with diseases of the posterior segment (e.g., posterior uveitis) or intraocular foreign bodies the results of computer and manual analysis are also practically identical. There are two computer analysis techniques: for subjects with almost normal EOGs the trigger-independent method is sufficiently accurate. In patients with pathologic EOGs, however, and in particular those with small potential differences, the trigger-related method is more likely to lead to correct results. The analysis path can be displayed on the computer monitor at any time, so that the examiner can always check whether it is correct. In contrast to manual analysis, the computer analysis cannot be influenced subjectively by the examiner. This considerably improves the comparability of examination results. A further advantage of computer analysis is its speed: the result is available immediately following the examination. It is a low-cost system which is easy to install and use, and thus suitable for routine clinical work.  相似文献   
105.
Patulin (PAT), a mycotoxin found in apples, grapes, oranges, pear and peaches, is a potent genotoxic compound. WHO has highlighted the need for the study of cutaneous toxicity of PAT as manual labour is employed during pre and post harvest stages, thereby causing direct exposure to skin. In the present study cutaneous toxicity of PAT was evaluated following topical application to Swiss Albino mice. Dermal exposure of PAT, to mice for 4 h resulted in a dose (40-160 μg/animal) and time (up to 6 h) dependent enhancement of ornithine decarboxylase (ODC), a marker enzyme of cell proliferation. The ODC activity was found to be normal after 12 and 24 h treatment of patulin. Topical application of PAT (160 μg/100 μl acetone) for 24-72 h caused (a) DNA damage in skin cells showing significant increase (34-63%) in olive tail moment, a parameter of Comet assay (b) significant G 1 and S-phase arrest along with induction of apoptosis (2.8-10 folds) as shown by annexin V and PI staining assay through flow cytometer. Moreover PAT leads to over expression of p21/WAF1 (3.6-3.9 fold), pro apoptotic protein Bax (1.3-2.6) and tumor suppressor wild type p53 (2.8-3.9 fold) protein. It was also shown that PAT induced apoptosis was mediated through mitochondrial intrinsic pathway as revealed through the release of cytochrome C protein in cytosol leading to enhancement of caspase-3 activity in skin cells of mice. These results suggest that PAT has a potential to induce DNA damage leading to p53 mediated cell cycle arrest along with intrinsic pathway mediated apoptosis that may also be correlated with enhanced polyamine production as evident by induction of ODC activity, which may have dermal toxicological implications.  相似文献   
106.

Background  

The efficacy, safety and tolerability of lumiracoxib, a novel selective cyclooxygenase-2 (COX-2) inhibitor, has been demonstrated in previous studies of patients with osteoarthritis (OA). As it is important to establish the long-term safety and efficacy of treatments for a chronic disease such as OA, the present study compared the effects of lumiracoxib at doses of 100 mg once daily (o.d.) and 100 mg twice daily (b.i.d.) with those of celecoxib 200 mg o.d. on retention on treatment over 1 year.  相似文献   
107.
Bardet–Biedl syndrome (BBS) is a rare pleiotropic disorder known as a ciliopathy. Despite significant genetic heterogeneity, BBS1 and BBS10 are responsible for major diagnosis in western countries. It is well established that eight BBS proteins, namely BBS1, 2, 4, 5, 7, 8, 9, and 18, form the BBSome, a multiprotein complex serving as a regulator of ciliary membrane protein composition. Less information is available for BBS6, BBS10, and BBS12, three proteins showing sequence homology with the CCT/TRiC family of group II chaperonins. Even though their chaperonin function is debated, scientific evidence demonstrated that they are required for initial BBSome assembly in vitro. Recent studies suggest that genotype may partially predict clinical outcomes. Indeed, patients carrying truncating mutations in any gene show the most severe phenotype; moreover, mutations in chaperonin-like BBS proteins correlated with severe kidney impairment. This study is a critical review of the literature on genetics, expression level, cellular localization and function of BBS proteins, focusing primarily on the chaperonin-like BBS proteins, and aiming to provide some clues to understand the pathomechanisms of disease in this setting.  相似文献   
108.
Guidelines recommend vaccination starting 12 months after autologous hematopoietic stem cell transplant (aHCT), but there is varying practice for patients on maintenance therapy, with some centers not immunizing at all. Because of decreased vaccine rates among the general population causing loss of herd immunity, we aimed to establish the safety and efficacy of revaccinating multiple myeloma patients on lenalidomide maintenance (LM). Of the 122 patients who were vaccinated after aHCT between 2010 and 2014 at Memorial Sloan Kettering Cancer Center, 91 (75%) were on LM. Vaccine responses were defined by increases between pre- and postvaccination titers. Reponses varied by vaccine type with 76% responding to pertussis, 70% diphtheria, 60% tetanus, 71% Haemophilus influenzae, and 58% pneumococcal. All patients retained minimal levels of polio immunity, but 27% responded with increased titers. Fewer patients received hepatitis A and B, but of those who did, 30% responded to hepatitis A and 40% to hepatitis B. No differences were seen in rates of response for those on LM at time of vaccination compared with those who were not. There were no vaccine-related adverse effects. Reimmunization with inactivated vaccines in patients on LM is therefore both safe and effective, offering this population immunity to vaccine-preventable diseases.  相似文献   
109.
110.

Background and objective

Hypertension is not a typical feature of steroid sensitive nephrotic syndrome (SSNS) and the presence of persistent hypertension is suggestive of significant renal lesion. There is paucity of data regarding occurrence and severity of hypertension in SSNS in pediatric population during remission and was the main objective of this study. In addition, correlation with factors like family history, BMI, and lipid profile was studied.

Methods

Cross-sectional study conducted at tertiary care center in India including 81 children of infrequent relapsing SSNS between 1 and 10 years in remission and was off steroids. Grading and severity of hypertension were assessed. Statistical analysis was done using SPSS version 21.0.

Results

Median age of presentation was 5 years, with male:female ratio of 1.3:1. Out of 81 infrequent relapsing SSNS children, 23.45% (19) had hypertension. Among those children with hypertension (n?=?19), 73.68% (14) had positive family history compared to 32.25% (20) in those without hypertension. Positive correlation was found between BP and serum cholesterol and LDL. Of the hypertensive patients, 1 (5.26%) had fundus changes, 2 (10.52%) had features of left ventricular hypertrophy, and 13 (68.42%) had non-nephrotic range proteinuria.

Conclusion

There is high incidence of hypertension in NS children during remission. Though significant positive correlation was found with positive family history of hypertension and deranged lipid profile highlighting possibility of essential hypertension in them, there is need for close active monitoring and management of hypertension in them as untreated cases may have significant target organ damage.
  相似文献   
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