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31.
Severe aplastic anemia is a well-recognized complication of ticlopidine therapy that carries a high mortality. Therapy with colony-stimulating factors or corticosteroids has been largely ineffective in this disorder. We report a case of ticlopidine-induced aplastic anemia that was successfully treated with cyclosporine and high-dose dexamethasone. The patient rapidly responded to immunosuppressive therapy and had a normal hemogram after cessation of immunosuppression. On long-term follow-up, the patient developed a progressive macrocytic anemia. Repeat bone marrow evaluation demonstrated myelodysplasia with erythroid hypoplasia. An associated chromosomal abnormality consisting of a t(3;16) (q21; p13.3) translocation was detected. This is the first report of a chromosomal abnormality associated with ticlopidine induced marrow aplastic anemia.  相似文献   
32.
OBJECTIVES: The purpose of this study was to objectively quantify the similarity of 12-lead electrocardiogram (ECG) waveforms using two quantitative metrics, the correlation coefficient (CORR) and the mean absolute deviation (MAD). BACKGROUND: Comparison of the 12-lead ECG morphology between ventricular tachycardia (VT) and a pace-map is frequently performed; however, there are no objective criteria for quantifying the similarity between two waveform morphologies. METHODS: During ablation of right ventricular outflow tract (RVOT) VT, 12-lead ECG pace-maps were acquired from three superior septal sites, three superior free wall sites, and before each ablation attempt in 15 patients. The 12-lead ECG waveforms of the clinical tachycardia and pace-maps were compared using both MAD and CORR at each site. RESULTS: The MAD scores were lower (i.e., more closely matched) for septal compared with free wall sites (15.9 +/- 5.3% vs. 25.3 +/- 10.2%; p < 0.001). Successful ablation sites had a significantly lower MAD score compared with unsuccessful sites (9.5 +/- 2.8% vs. 13.3 +/- 5.6%; p = 0.01), whereas there was only a trend toward a higher CORR for successful ablation sites (98.2 +/- 1.2% vs. 96 +/- 4.7%; p = 0.07). A MAD score < or =12% was 93% sensitive and 75% specific for identifying a successful ablation site. There was an inverse correlation between MAD score and distance from the site of VT origin (r = 0.63, p < 0.001). CONCLUSIONS: A MAD score >12% between RVOT VT and a pace-map at any site suggests sufficient dissimilarity to dissuade ablation at that site. The MAD score can be used to standardize 12-lead ECG waveform morphology comparisons among different laboratories, and may be useful for guiding ablation of VT.  相似文献   
33.

Background

Personally controlled health management systems (PCHMSs) contain a bundle of features to help patients and consumers manage their health. However, it is unclear how consumers actually use a PCHMS in their everyday settings.

Objective

To conduct an empirical analysis of how consumers used the social (forum and poll) and self-reflective (diary and personal health record [PHR]) features of a Web-based PCHMS designed to support their physical and emotional well-being.

Methods

A single-group pre/post-test online prospective study was conducted to measure use of a Web-based PCHMS for physical and emotional well-being needs during a university academic semester. The PCHMS integrated an untethered PHR with social forums, polls, a diary, and online messaging links with a health service provider. Well-being journeys additionally provided information to encourage engagement with clinicians and health services. A total of 1985 students and staff aged 18 and above with access to the Internet were recruited online, of which 709 were eligible for analysis. Participants’ self-reported well-being, health status, health service utilization, and help-seeking behaviors were compared using chi-square, McNemar’s test, and Student’s t test. Social networks were constructed to examine the online forum communication patterns among consumers and clinicians.

Results

The two PCHMS features that were used most frequently and considered most useful and engaging were the social features (ie, the poll and forum). More than 30% (213/709) of participants who sought well-being assistance during the study indicated that other people had influenced their decision to seek help (54.4%, 386/709 sought assistance for physical well-being; 31.7%, 225/709 for emotional well-being). Although the prevalence of using a self-reflective feature (diary or PHR) was not as high (diary: 8.6%, 61/709; PHR: 15.0%, 106/709), the proportion of participants who visited a health care professional during the study was more than 20% greater in the group that did use a self-reflective feature (diary: P=.03; PHR: P<.001).

Conclusions

There was variation in the degree to which consumers used social and self-reflective PCHMS features but both were significantly associated with increased help-seeking behaviors and health service utilization. A PCHMS should combine both self-reflective as well as socially driven components to most effectively influence consumers’ help-seeking behaviors.  相似文献   
34.
35.

Objective:

To evaluate the diagnostic accuracy of three-dimensional (3D) enhanced T1 high-resolution isotropic volume excitation (eTHRIVE) shoulder MR for variable shoulder pathology such as rotator cuff tear, labral injury and synovial pathology in comparison with two-dimensional enhanced fast spin echo T1 fat saturation (2D T1 FS) sequences MR.

Methods:

This retrospective study included 86 patients who underwent MRI of the shoulder using eTHRIVE technique. Two radiologists evaluated anatomic identification of the supraspinatus, glenoid labrum and acromioclavicular joint (AC joint) on routine MRI sequences (2D T1 FS) and compared them with the reformatted eTHRIVE images. Subjective scoring of the images was performed with a four-point scale that rated the degree of discrimination of the shape of the supraspinatus, glenoid labrum and AC joint. The diagnostic accuracy of eTHRIVE compared with routine MR images was evaluated in terms of rotator cuff pathology, labral pathology and synovial pathology.

Results:

Anatomic identification scores of the supraspinatus tendon and labrum were significantly lower for eTHRIVE than for 2D T1 FS. There were no significant differences between eTHRIVE and 2D T1 FS in anatomic identification of the AC joint. There were no significant differences between eTHRIVE and 2D T1 FS in diagnosing the three disease categories.

Conclusion:

eTHRIVE had comparable diagnostic accuracy to 2D T1 FS imaging in the evaluation of rotator cuff tears, labral injury and synovial pathology, but anatomic identification was inferior to that of 2D T1 FS.

Advances in knowledge:

The accuracy of 3D eTHRIVE imaging is comparable to that of 2D T1 FS for the diagnosis of rotator cuff tears, labral injury and synovial pathology.  相似文献   
36.
ObjectiveWe described the technique of ultrasound (US)-guided percutaneous removal of the foreign bodies (FB) with hydro-dissection in the radiologic department and presented video files of several cases.ResultsThe mean time required for the entire procedure was approximately 20 minutes. There were no significant complications during the US-guided removal or long-term complications after the procedure. All 4 FBs were successfully removed from the soft tissue under US guidance.ConclusionUltrasound-guided percutaneous removal of the FBs with hydro-dissection in the radiology department is a less invasive and safe method over surgical removal in the operating room. Additionally, the use of a guide wire and serial dilator may help minimize soft tissue injury and facilitate the introduction of forceps.  相似文献   
37.

Background

Online health information–seeking behaviors have been reported to be more common at the beginning of the workweek. This behavior pattern has been interpreted as a kind of “healthy new start” or “fresh start” due to regrets or attempts to compensate for unhealthy behavior or poor choices made during the weekend. However, the observations regarding the most common health information–seeking day were based only on the analyses of users’ behaviors with websites on health or on online health-related searches. We wanted to confirm if this pattern could be found in searches of Wikipedia on health-related topics and also if this search pattern was unique to health-related topics or if it could represent a more general pattern of online information searching—which could be of relevance even beyond the health sector.

Objective

The aim was to examine the degree to which the search pattern described previously was specific to health-related information seeking or whether similar patterns could be found in other types of information-seeking behavior.

Methods

We extracted the number of searches performed on Wikipedia in the Norwegian language for 911 days for the most common sexually transmitted diseases (chlamydia, gonorrhea, herpes, human immunodeficiency virus [HIV], and acquired immune deficiency syndrome [AIDS]), other health-related topics (influenza, diabetes, and menopause), and 2 nonhealth-related topics (footballer Lionel Messi and pop singer Justin Bieber). The search dates were classified according to the day of the week and ANOVA tests were used to compare the average number of hits per day of the week.

Results

The ANOVA tests showed that the sexually transmitted disease queries had their highest peaks on Tuesdays (P<.001) and the fewest searches on Saturdays. The other health topics also showed a weekly pattern, with the highest peaks early in the week and lower numbers on Saturdays (P<.001). Footballer Lionel Messi had the highest mean number of hits on Tuesdays and Wednesdays, whereas pop singer Justin Bieber had the most hits on Tuesdays. Both these tracked search queries also showed significantly lower numbers on Saturdays (P<.001).

Conclusions

Our study supports prior studies finding an increase in health information searching at the beginning of the workweek. However, we also found a similar pattern for 2 randomly chosen nonhealth-related terms, which may suggest that the search pattern is not unique to health-related searches. The results are potentially relevant beyond the field of health and our preliminary findings need to be further explored in future studies involving a broader range of nonhealth-related searches.  相似文献   
38.
39.
NADPH oxidase (NOX) plays an important role in inflammatory response by producing reactive oxygen species (ROS). The inhibition of NOX has been shown to induce anti‐inflammatory effects in a few experimental models. The aim of this study was to investigate the effects of diphenyleneiodonium (DPI), a NOX inhibitor, on lipopolysaccharide (LPS)‐induced acute lung injury (ALI) in a rat model. Sprague‐Dawley rats were intraperitoneally administered by DPI (5 mg/kg) 30 minutes after intratracheal instillation of LPS (3 mg/kg). After 6 hours, bronchoalveolar lavage fluid (BALF) and lung tissue were collected. The NOX activity in lung tissue was significantly increased in LPS‐treated rats. It was significantly attenuated by DPI. DPI‐treated rats showed significant reduction in the intracellular ROS, the number of inflammatory cells, and cytokines (TNF‐α and IL‐6) in BALF compared with LPS‐treated rats. In lung tissue, DPI‐treated rats showed significantly decreased malondialdehyde content and increased activity of glutathione peroxidase and superoxide dismutase compared with LPS‐treated rats. Lung injury score, myeloperoxidase activity, and inducible nitric oxide synthase expression were significantly decreased in DPI‐treated rats compared with LPS‐treated animals. Western blotting analysis demonstrated that DPI significantly suppressed LPS‐induced activation of NF‐κB and ERK1/2 and SAPK/JNK in MAPK pathway. Our results suggest that DPI may have protective effects on LPS‐induced ALI thorough anti‐oxidative and anti‐inflammatory effects which may be due to inactivation of the NF‐κB, ERK1/2, and SAPK/JNK pathway. These results suggest the therapeutic potential of DPI as an anti‐inflammatory agent in ALI.  相似文献   
40.
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