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991.
We prospectively studied 16 patients with isolated aortic stenosis and eight with isolated aortic regurgitation undergoing aortic valve replacement, using two-dimensional echocardiography preoperatively, intraoperatively, and 41 +/- 7 days postoperatively to calculate the intraoperative change in afterload, quantify the postoperative changes in left ventricular chamber size, architecture, load and function, determine whether the postoperative left ventricular remodeling correlated with the intraoperative change in afterload in aortic stenosis and aortic regurgitation, and assess whether preoperative afterload excess precluded postoperative improvement in left ventricular function. Preoperative left ventricular mass, end-systolic meridional and circumferential wall stresses, ejection fraction, and stress-shortening relations in patients with aortic stenosis and aortic regurgitation were similar. However, our patients with aortic regurgitation had severe systolic dysfunction, with ejection fraction less than 55% in all but one patient, compared with only 10 of 16 patients with aortic stenosis. Left ventricular end-diastolic volume, mass/volume ratio, and chamber shape were significantly different in patients with aortic stenosis and aortic regurgitation (174 +/- 64 vs 294 +/- 140 ml, p less than .01; 1.81 +/- 0.63 vs 1.14 +/- 0.18, p less than .01; and 0.59 +/- 0.09 vs 0.69 +/- 0.09, p less than .05, respectively). Intraoperative end-systolic meridional and circumferential stresses fell significantly in patients with aortic stenosis but remained unchanged in those with aortic regurgitation. The changes in left ventricular volume and ejection fraction during early postoperative remodeling (6 weeks) correlated with the intraoperative change in afterload in patients with aortic stenosis. In contrast, there was no intraoperative change in afterload in patients with aortic regurgitation and no significant changes in left ventricular volume, architecture, or function at 6 weeks or at 6 months. The differences in left ventricular remodeling and changes in function between patients with aortic stenosis and aortic regurgitation in the early postoperative period most probably relates to the major difference in intraoperative reduction in afterload, although a contributory role may have been played by the preoperative left ventricular dysfunction in those with aortic regurgitation that was underestimated by measurement of ejection fraction.  相似文献   
992.
993.
Management of anxiety in dental practice in the UK   总被引:1,自引:0,他引:1  
A postal questionnaire was sent to a random sample of dentists in the United Kingdom. The response rate was 59.9%. Anxiety was reported as a significant problem by 66% of dentists and information was gained regarding the techniques used to manage this anxiety. 'Patient management' and general anaesthesia were the techniques most commonly employed. The frequency of usage of intravenous and inhalational sedation varied according to the age of the patient. Only 55.3% of dentists in general practice had any training in a sedative technique.  相似文献   
994.
Twenty-four anxious dental patients requiring emergency extractions for the relief of pain were offered inhalation sedation with 25 per cent nitrous oxide as an alternative to general anaesthesia. The treatment of 22 patients was successfully completed by 2 final year dental students. Twenty patients (83 per cent) expressed a marked preference for the technique rather than general anaesthesia which they had also experienced.  相似文献   
995.
Objectives: The purpose of the study was to evaluate the intra- and inter-examiner variability of a panel of examiners using a ‘glance and grade' marking system when assessing Class II preparations.

Methods: The examination panel consisted of five university staff with varying clinical and teaching experience. The panel assessed 75 disto-occlusal preparations suitable for restoration with dental amalgam prepared in extracted human premolar teeth. The majority of the preparations were cut by undergraduates in their preclinical year of study and the remainder by an experienced staff member. The panel were blind to the identity of each operator.

Results: The study revealed a high degree of both intra- and inter-examiner variability, with some preparations being given a pass on one occasion and a fail on another and vice-versa. In addition, some of the panel, perhaps assuming that the practical exercise had been prepared entirely by undergraduates, were reluctant to award good grades.

Conclusions: The study has highlighted the need for better staff training and a more comprehensive system of assessing preclinical skills.  相似文献   

996.
Dental health education employing five different teaching methods was given to classes of 9- to 10-year-old schoolchildren. A control class received no teaching. The dental health knowledge of the classes was assessed before teaching, and immediately, 1 week and 3 months after teaching by the use of a questionnaire. All methods resulted in a variable increase in marks immediately after teaching. This was followed by a fall in marks for each class over the 3-month period. The poster and pack methods of presenting information, overall, had little or no effect on the recall of information. The talk, visual aids and project methods all significantly increased dental health knowledge for the 3-month period.  相似文献   
997.
998.
999.
Purpose: To determine if a community screening with Frequency Doubling Technology perimetry (FDT) results in a high proportion of follow-up with an eye care provider and the factors associated with follow-up. Design:Cross-sectional study. Setting: Telephone survey Methods: We conducted a telephone survey of participants with abnormal results 3–6 months after the community screening. Results: We were able to interview 121 participants (57% of 212 eligible subjects). Sixty-nine percent (83 of 121) of participants visited an eye care provider after the screening. Patients were more likely to attain an eye exam if they were female, older, or had an educational level of high school or more (p < 0.05). Of those participants who did not visit an eye care provider, 41% (18/38) did not believe the results of the test, 21% (8/38) reported not having insurance or an eye care provider, 11% (4/38) did not have time for an eye exam, and 11% (4/38) reported not knowing they needed to see an eye care provider. Conclusion: A community screening program with FDT encouraged more than two thirds of participants with abnormal results to seek an eye exam. The most common reason not to attain an eye exam was failing to recognize the importance of an abnormal test result.  相似文献   
1000.
We present a new surgical approach for Dupuytren's disease which overcomes some of the problems seen with traditional approaches. The approach is simple but allows full exposure and accommodates all options for closure. It comprises transverse incisions at the skin creases of the digit joined by oblique incisions at 45°. The transverse incisions can be extended to the mid-axial line for improved exposure and skin release and to lateralize the apices of the scar. After excision of the disease and correction of the contracture the wound can be assessed and closed primarily, with advancement flaps or skin grafts, or left partially open. This study includes surgery on 105 rays in 75 patients with excellent results in 80 rays, good results in 20 rays, fair results in four rays and a poor result in one ray. There was only one significant complication.  相似文献   
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