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排序方式: 共有786条查询结果,搜索用时 15 毫秒
61.
BACKGROUND: Spontaneous echo contrast (SEC) is common in patients with mitral stenosis (MS) and presence of SEC in left atrium (LA) is associated with a higher risk of thromboembolism. Recently, an increase in activation of platelets was demonstrated in patients with SEC raising the hypothesis that platelets are involved in the pathogenesis of SEC. In this study, we evaluated effects of autonomic nervous system activity on SEC formation in patients with rheumatic MS and sinus rhythm by heart rate variability analysis. METHODS AND RESULTS: Twenty-six patients with LASEC were compared with 28 patients without LASEC. Mean heart rate, low frequency (LF) and low frequency/high frequency (LF/HF) ratio were significantly higher, standard deviation of all NN (SDNN), root mean square of successive differences (RMSSD), number of NN intervals that differed by more than 50 ms from adjacent interval divided by the total number of all NN intervals (PNN50) and high frequency (HF) values were lower in the patients with LASEC. A standard deviation of all NN intervals <90ms separated the patients with LASEC from control subjects with a sensitivity of 77% and specificity of 90%; a low frequency >79.5 with a sensitivity of 92% and specificity of 90; a low frequency/high frequency ratio >3.7 with a sensitivity of 96% and specificity of 90%. A left atrial diameter >4.3 cm increased the LASEC formation by 3.0 folds, HR >78 beats/min by 6.4 folds, standard deviation of all NN intervals <90 ms by 9.2 folds, a low frequency/high frequency ratio >3.7 by 6.4 folds, sP-selectin>142 by 5.8 folds. Variables affecting sP-selectin levels were LA diameter, mitral valve area, transmitral mean gradient, left ventricular ejection fraction, the presence of mitral regurgitation, HR, standard deviation of all NN intervals, low frequency, high frequency and low frequency/high frequency ratio. CONCLUSION: Sympathetic overactivity and reduced heart rate variability are important determinants for LASEC formation and increased s-P selectin levels. Therefore, platelet activation via increased sympathetic activity may play an important role in pathogenesis of LASEC.  相似文献   
62.
The electrocardiographic changes early after uncomplicated coronary artery bypass with complete revascularization were examined preoperatively and on the 1st and 3rd postoperative days in 53 patients. Heart rate, PR index, corrected PR interval, corrected P dispersion, corrected duration of QRS complex, corrected QT dispersion, corrected QT interval, rhythm, QRS axis, ST-segment changes, and blocks were determined. Changes in new parameters obtained by different combinations of R, S, and T waves were also studied. On the 1st postoperative day, atrial fibrillation was significantly less prevalent, right bundle branch block increased significantly, and QRS axis was significantly more positive but returned to baseline on the 3rd postoperative day. Postoperative heart rate and PR index were significantly higher than preoperative values. In the postoperative period, corrected PR interval was significantly lower, corrected QRS complex duration was significantly shorter, corrected QT interval was significantly longer, and corrected QT dispersion showed a significant increase on the 1st postoperative day. This study defines electrocardiographic changes in uncomplicated patients with complete revascularization. Any deviations from these findings may alert us to the need for further evaluation of an undesired event.  相似文献   
63.
ObjectivesThe aim of our study was to determine the diurnal variation of lipoprotein-associated phospholipase A2 (Lp-PLA2), an arterial-specific inflammatory enzyme implicated in the formation of vulnerable, rupture-prone plaque that can identify individuals at high risk for cardiovascular disease. Presently, the diurnal variation of Lp-PLA2 is not known.Design and MethodsTen men and 8 women (age range: 22–76 years) had a blood sample taken every 4 h over a 24-hour time period. Samples were analyzed for both Lp-PLA2 mass and activity.ResultsThe mean coefficient of variation (CV) for Lp-PLA2 mass was 5.9% (ranges from 2.5 to 9.4%) for the 18 subjects. Similarly, the mean CV for Lp-PLA2 activity was 3.7% (ranges from 1.2 to 6.8%). There were no significant correlations between CV and any of the subject characteristics.ConclusionsThe diurnal variation of Lp-PLA2 mass and activity is similar to that of well accepted lipoprotein risk factors. With the relatively low diurnal variability, there does not appear to be a need to make sure serial measurements of Lp-PLA2 mass and activity are taken at the same time of the day.  相似文献   
64.
Coronary artery aneurysms are defined as coronary dilatations which exceed the diameter of normal adjacent segments by 1.5 times. Left main coronary artery (LMCA) is the least frequently involved artery with a prevalence of 0.1%. Majority of coronary artery aneurysms are atherosclerotic in origin. Their size and clinical presentation is variable. A number of complications have been reported to occur during the course of the disease including thrombosis and distal embolization, myocardial ischemia and/or infarction, dissection, vasospasm, calcification, fistulization and very rarely rupture. Large aneurysms of LMCA represent a potentially fatal condition even without concomitant atherosclerotic coronary disease. Because of rarity of coronary artery aneurysms, it is difficult to standardize treatment. In this article, we presented 4 cases of large LMCA aneurysms with various clinical and angiographic features.  相似文献   
65.
Ascending aortic dissection is often a catastrophic condition. Dissection into the commissures or into an aortic valve leaflet may lead to leaflet avulsion and valvular insufficiency due to a flail valve. We present an image report describing an important and life-threatening complication due to the movement of a partially dehisced intimal aortic flap into the left ventricle causing aortic valve insufficiency in a patient with acute dissection of the ascending aorta.  相似文献   
66.
Psoriatic arthritis is an autoimmune, chronic, systemic inflammatory disorder characterized by the association of arthritis with psoriasis. In this paper, we explore the characteristics of joint and nail involvement in Turkish patients with psoriatic arthritis. Forty patients with psoriasis (M/F, 18/22) and 49 (M/F, 25/24) subjects with psoriatic arthritis were included in the study. Clinical characteristics of the patients were recorded. The distribution of the subjects with arthritis: (according to the clinical and radiological findings): polyarticular, 65%; oligoarticular, 23%; isolated axial involvement, 7.7%; arthritis mutilans, 3.8%; sacroiliitis, 19%. Nail involvement was significantly higher among patients with arthritis; i.e., 91 versus 32%; (P < 0.05). There were no correlation between the skin involvement pattern and the arthritis type (P > 0.05). Nevertheless, no relation was observed between the psoriasis duration and arthritis (P > 0.05). Nail involvement is a frequent feature of the psoriatic arthritis which may be a useful finding for differential diagnosis of psoriatic arthritis from other inflammatory arthropathies.  相似文献   
67.
Background: In patients with acute myocardial infarction (AMI), intraaortic balloon counterpulsation (IABC) may improve cardiac performance, decrease the incidence of recurrent ischemia, and improve survival. Although there have been several reports concerning circulatory maintenance with the IABC, response of the autonomic nervous system to these hemodynamic changes is not clear. Heart rate variability (HRV) analysis has been extensively used to evaluate autonomic modulation of sinus node and to identify patients at risk for an increased cardiac mortality. In this study, we evaluated effects of the IABC on autonomic nervous system functions by HRV analysis. Methods: The study group was composed of 32 consecutive patients (13 female, 19 male aged 61.8 ± 8.8 years) undergoing IABC. Transthoracic echocardiography and 1‐hour Holter recordings for HRV analysis in each IAB pumping mode were obtained. Results: The IABC improved left ventricular diastolic and systolic functions as well as caused an increase in SDNN1, PNN50(1), RMSSD1, and HF1 and a decrease in LF1, LF/HF1, mean heart rate, and the number of ventricular extrasystoles. The improvements in HRV parameters were correlated with some hemodynamic changes such as the increase in MAP and CO during counterpulsation. The only independent factors affecting in‐hospital mortality were the change in LF/HF1 ratio (ΔLF/HF1) and the change in the number of ventricular extrasystole (ΔVES). The decrease in LF/HF1 ≥4.9 decreased the mortality by 1.7‐folds (RR = 0.6, P = 0.04, 95% CI: 0.1–2.3). The decrease in VES ≥27/15 minutes resulted in mortality reduction by 16‐folds (RR = 0.06, P = 0.02, 95% CI: 0.01–0.4). Conclusions: As a result, the IABC, especially in 1:1 support, causes an increase in HRV, decrease in sympathetic overactivity, and improvement in sympathovagal balance besides the favorable hemodynamic changes, and these electrophysiologic changes may explain the role of the IABC in the treatment of ventricular arrhythmias.  相似文献   
68.
There is increased risk of systemic embolism during cardiopulmonary bypass in patients with a severely atherosclerotic ascending aorta. We report a coronary-coronary bypass in a 74-year-old man with a porcelain aorta. He underwent a proximal right coronary-distal right coronary artery bypass with a saphenous vein graft, combined with a pedicled arterial graft (left internal mammary artery) to the left anterior descending artery, in the presence of a beating heart without cardiopulmonary bypass. The patient survived without evidence of perioperative myocardial infarction or cerebrovascular accident. One year later, follow-up angiography showed graft patency with good distal run-off. Coronary-coronary bypass on a beating heart without cardiopulmonary bypass can be performed safely in a patient with porcelain aorta.  相似文献   
69.
Evaluation of the clinical presentations in neurobrucellosis.   总被引:1,自引:0,他引:1  
BACKGROUND: Brucellosis is a multisystem disease that may present with a broad spectrum of clinical manifestations and complications. Neurobrucellosis is one of the complications. METHODS: In this study, we describe our experience in the diagnosis, treatment, and the final outcomes of 20 patients with neurobrucellosis out of 305 patients with brucellosis, within a five-year period between January 1999 and June 2004. RESULTS: The rate of neurobrucellosis was 6.6%. Twelve males and eight females with a mean age of 37.4 years were investigated. Fever, headache, confusion, and gait disorders were the main complaints. The duration of their complaints varied between one week and six months. On physical examination, 13 patients had fever, six had neck stiffness and confusion, three had motor deficit on either their upper or lower extremities, and four of them had diplopia. The Rose-Bengal test and standard tube agglutination tests were positive in all of the patients. Brucella melitensis was isolated from the blood of six of the 20 (30%) patients. Cerebrospinal fluid (CSF) was analyzed in 18 patients. Pleocytosis with a mean value of 244x10(6)cells/L, and high protein levels were detected in all. A low glucose level in the CSF was detected in ten patients. Patients were treated medically and a complete resolution was achieved in all. CONCLUSION: Patients with a Brucella infection occasionally manifest central nervous system involvement. Clinicians, especially serving in endemic areas or serving patients coming from endemic areas should consider the likelihood of neurobrucellosis in the patients with unexplained neurological and psychiatric symptoms, and should perform the necessary tests on blood and CSF.  相似文献   
70.
Bagis  Nilsun  Kurt  Mehmet Hakan  Evli  Cengiz  Camgoz  Melike  Atakan  Cemal  Peker Ozturk  Hilal  Orhan  Kaan 《Oral Radiology》2022,38(3):325-335
Objective

The aim of this study is to assess the effects of metal artifact reduction (MAR) and adaptive image noise enhancer (AINO) in CBCT imaging on the detection accuracy of artificially created fenestration defects in proximity to titanium and zirconium implants in sheep jaw.

Methods

Six zirconium and 10 titanium implants were planted on mandibular jaws of three sheep, and artificial defects were created. All images were obtained with a standard voxel size (0.150 mm3) and with 4 scan modes: (1) without MAR/without AINO; (2) with MAR/without AINO; (3) without MAR/with AINO; and (4) with MAR/with AINO during CBCT scanning. A total of 60 CBCT scans were produced.

Results

For all types of implants, intra- and inter-observer kappa values were the highest for MAR filter. The scan mode of with MAR filter was found to have the highest area under the curve (AUC), whereas the scan mode of without both MAR and AINO filters was found to have the lowest AUC values with statistical significance (p?≤?0.05). Titanium implants were found to have higher AUC values than zirconium (p?≤?0.05).

Conclusion

Both MAR module and AINO filters enhance the accuracy of the detection of peri-implant fenestrations; however, the use of MAR filter solely can be recommended for detection of peri-implant fenestrations.

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