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71.
del Nido PJ Duncan BW Mayer JE Wessel DL LaPierre RA Jonas RA 《The Annals of thoracic surgery》1999,67(1):169-172
BACKGROUND: Repair of anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) in infants carries a high operative risk, particularly in infants with myocardial infarction and poor left ventricular function. The marked recovery of left ventricular function reported late after repair, however, suggests that an aggressive approach to repair should be undertaken. METHODS: Of 31 children undergoing primary repair of ALCAPA at our institution from 1987 to 1996, 26 were infants (6 weeks to 9 months old). All but 2 had severe left ventricular dysfunction, and 8 had moderate to severe mitral regurgitation. Seven children were unable to be weaned from cardiopulmonary bypass because of poor left ventricular function and elevated left atrial pressure. These 7 children were placed on mechanical left ventricular support using a centrifugal pump, with support ranging from 2.2 to 70.6 hours. RESULTS: One child died shortly after the start of left ventricular assist (2.2 hours), and another died of arrhythmia within 24 hours after successful decannulation. All 5 survivors had significant improvement in left ventricular function, with 2 requiring late mitral valve repair. CONCLUSIONS: Infants with ALCAPA who have severe left ventricular dysfunction represent a higher risk group for repair. However, with use of mechanical circulatory support in those unable to be weaned from cardiopulmonary bypass, a high survival rate can be achieved with good long-term recovery. We conclude that an aggressive approach to early repair in all children with ALCAPA is warranted, regardless of the degree of left ventricular dysfunction. 相似文献
72.
Sinus of Valsalva aneurysm or fistula: management and outcome 总被引:9,自引:0,他引:9
Takach TJ Reul GJ Duncan JM Cooley DA Livesay JJ Ott DA Frazier OH 《The Annals of thoracic surgery》1999,68(5):1573-1577
BACKGROUND: Few large or long-term series exist regarding the management of patients with sinus of Valsalva aneurysms or fistulas (SVAFs). METHODS: Between 1956 and 1997, 129 patients presented with a ruptured (64 cases; 49.6%) or nonruptured (65 cases; 50.4%) SVAF. The patients included 88 men and 41 women, with a mean age of 39.1 years. Associated findings included a history of endocarditis (42 cases; 32.6%), a bicuspid aortic valve (21 cases; 16.3%), a ventricular septal defect (15 cases; 11.6%), and Marfan's syndrome (12 cases; 9.3%). Operative procedures included simple plication (61 cases; 47.3%), patch repair (52 cases; 40.3%), aortic root replacement (16 cases; 12.4%), and aortic valve replacement/repair (75 cases; 58.1%). RESULTS: There were five in-hospital deaths (3.9%): four due to preexisting sepsis and endocarditis and one that followed dehiscence of the repair in a patient with Marfan's syndrome. Two patients (1.6%) had strokes during the early postoperative period. The survivors were followed up for 661.1 patient-years (5.3 years/patient). The following late complications occurred: prosthetic valve malfunction (5 cases; 3.9%), prosthetic valve endocarditis (3 cases; 2.3%), SVAF recurrence (2 cases; 1.6%), thrombosis (1 case; 0.8%), and anticoagulation-related bleeding (1 case; 0.8%). CONCLUSIONS: Resection and repair of SVAF entails an acceptably low operative risk and yields long-term freedom from symptoms. Early, aggressive treatment is recommended to prevent endocarditis or lesional enlargement, which causes worse symptoms and necessitates more extensive repair. 相似文献
73.
74.
The treatment of periprosthetic fractures of the femur using cortical onlay allograft struts 总被引:9,自引:0,他引:9
Periprosthetic fractures of the femur are a complex problem to treat. Careful planning is essential before embarking on such a technically demanding procedure. There are many factors to be considered, including the premorbid condition of the patient and previous experience and training of the surgeon. Important factors relating directly to the fracture include the site, stability of the implant, and the state of the surrounding bone stock. 相似文献
75.
D S Friedman D D Duncan B Munoz S K West O D Schein 《Investigative ophthalmology & visual science》1999,40(8):1715-1726
PURPOSE: To develop and validate a digital imaging and analysis technique for assessing the extent of posterior capsular opacification after cataract surgery. METHODS: Retroillumination images of the posterior capsule were obtained by using a digital camera mounted on a slit lamp. The images were analyzed using an available image analysis software program. The image acquisition and analysis techniques were tested for face validity, reproducibility, and the ability to detect progression of capsular opacity over time. RESULTS: Digital retroillumination images were obtained without patient discomfort. Automated analysis of images correlated well with clinical grading both at slit lamp examination and when looking at the images themselves (Spearman's correlation coefficient >0.7). Analysis of images taken at different times showed high reproducibility (intraclass correlation >0.9), and the system was able to identify progression of capsular opacity over a 2-year period with a mean increase of 15.8% in progressors versus an increase of 0.6% in nonprogressors (P < 0.05). CONCLUSIONS: Digital retroillumination images of the posterior capsule can be obtained reliably, and automated analyses correlate well with clinical assessment. The system presented here uses commercially available instruments and software, and it is practical for use in longitudinal studies of posterior capsule opacification. It is reliable, easy to use, and can detect small changes in the percentage area covered by posterior capsule opacification over time. 相似文献
76.
77.
In utero arterial embolism from renal vein thrombosis with successful postnatal thrombolytic therapy
B W Duncan N S Adzick M T Longaker J R Edwards R M Nelson M A Koerper 《Journal of pediatric surgery》1991,26(6):741-743
Thromboembolic events in the pediatric age group occur most commonly in neonates, and newborns of diabetic mothers are particularly at risk. We report a newborn with right renal vein and inferior vena cava thrombosis who apparently embolized across the foramen ovale antenatally with resultant right brachial artery occlusion. The baby was delivered by cesarean section from an insulin-dependent diabetic mother. At the time of birth, there was severe right arm ischemia with absent brachial and radial pulses. There was clinical evidence of distal embolization with a "trash" lesion of the distal right middle finger as well as a midforearm area of full-thickness skin loss. Ultrasound demonstrated a right renal vein thrombosis and a 95% occlusion of the inferior vena cava. Regional urokinase therapy was instituted through a lower extremity vein with a 5,000 U/kg bolus and then 5,000 U/kg/h continuous infusion. Twelve hours of infusion of urokinase led to clinical resolution of the right arm ischemia, with return of pulses. Follow-up ultrasound showed the right renal vein thrombosis and inferior vena cava clot to be completely resolved. The right middle finger and forearm lesions subsequently have healed primarily. We report this as a case of in utero arterial embolization with successful postnatal therapy using regional urokinase infusion. 相似文献
78.
Pulse oximetry and capnography in anaesthetic practice: an epidemiological appraisal 总被引:1,自引:0,他引:1
In the evaluation of any medical technology the efficacy, effectiveness, and efficiency must each be considered before routine deployment is recommended. Since the widespread practice of patient monitoring by pulse oximetry and capnography has occurred before the performance of rigorously controlled trials, definitive proof of worth is lacking. The purpose of this review is to appraise critically the effectiveness of this technology. The assessment was performed using concepts developed in epidemiology and community medicine to establish a given factor to be causative to a given outcome. The current literature pertaining to anaesthetic adverse outcomes was reviewed, and the use of monitors evaluated against the criteria of a causal relationship. While the conclusions are based more on the absence of positive data (owing to low frequency of adverse anaesthetic occurrences) rather than negative results, it must be concluded that the effectiveness of such monitoring has yet to be demonstrated. Such a conclusion should not detract from their use, for the role of an individual factor in the complex chain of accident evolution will seldom be demonstrable. Rather, such an appraisal should encourage a clear perspective of the depth of our clinical science, and encourage more rigorous critical evaluation in the future. 相似文献
79.
J F Mahony F Duncan S Lawrence D Howes J H Stewart 《The Medical journal of Australia》1979,1(9):368-370
Thirty of the 39 patients treated at the Blacktown Dialysis Centre, the first "satellite" dialysis centre in the greater metropolitan Sydney, had been referred from four Sydney renal units for long-term dialysis therapy. The move save approximately 150 kilometres in travelling and eight hours time each week for each of these patients. The cost of running the unit was approximately $10,000 per patient per year in the first year--no greater than that of home dialysis, and less than that of dialysis in a teaching hospital. The advantages of establishing satellite dialysis centre, the method of operation, and the results of the first year of operation of the Blacktown Dialysis Centre are described. 相似文献
80.
Levin A Duncan L Djurdjev O Shapiro RJ Frohlich J Belanger A Dumas R Ross S 《Clinical nephrology》2000,53(2):140-146
BACKGROUND: Renal insufficiency is characterized by lipoprotein abnormalities including elevated triglyceride levels. PATIENTS AND METHODS: The safety and efficacy of micronized fenofibrate as a treatment for dyslipidemia in patients with progressive renal insufficiency was evaluated in a randomized, placebo-controlled double-blind study comparing fenofibrate and dietary modification to dietary modification alone. Patients were evaluated following a 3-month pre-randomization period of dietary counseling. Twenty-eight patients with moderate renal insufficiency and triglyceride levels 2.3 mmol/l or LDL/HDL ratio 5 were randomized to placebo (n = 12) or fenofibrate (n = 16) therapy. Treatment and dietary counseling continued for 6 months. RESULTS: Ten of 16 patients (63%) treated with fenofibrate achieved a 30% reduction in triglyceride levels or LDL/HDL ratio reduction < 5 compared to 2 of 17% in the placebo group (p = 0.015). Triglyceride levels were significantly reduced in the fenofibrate group (-31%) versus placebo (+1.3%, p = 0.003). In compliant patients (n = 25) there was also a significantly greater increase in HDL cholesterol levels in the fenofibrate group (+19.9%) compared to placebo (-4.7%, p = 0.001). Changes in measured creatinine clearance were not significantly different between the groups and there were no serious adverse effects of treatment. CONCLUSION: Fenofibrate therapy combined with dietary modification effectively reduced triglyceride levels in renal insufficiency patients without serious adverse effects. 相似文献