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Repeated pulmonic balloon valvuloplasty from the axillary vein was performed in two infants with initial transvalvular gradients of 131 and 162 mm Hg. The first angioplasty was performed through the femoral vein and improved the valve gradient in both patients. Because of obstruction of the iliac system the axillary vein approach was used for the second angioplasty. The transaxillary pulmonic valvuloplasty decreased the gradient to acceptable levels, and no complications were noticed. The axillary vein approach can be the alternative to the femoral one in cases with obstructed iliac system or interrupted inferior vena cava.  相似文献   
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GOAL: Evaluation of interferon alpha-2b adjuvant treatment (INF alpha-2b) toxicity by monitoring biologic parameters in patients with stage III melanoma. METHOD: Between January 7th till October 29th 1998, we administered 674 injections of INF alpha-2b to eight patients who previously had undergone surgery for stage III melanoma. Patients received 20 MU/m2/d IV for a month and 10 MU/m2/d sub-cutaneously three time a week for 48 weeks. All these patients were followed with at least one complete blood count and hepatic profile every week. Interferon alpha-2b doses were changed accordingly. RESULTS: Patients received on average 51.5% of the total dose. Doses were decreased in patients with neutropenia or hepatic profiles anomalies. Only one patient could received 100% of the total regimen. In four patients treatment was discontinued. In three out of four patients this was due to disease progression, and in one out of four patients this was due to hepatic toxicity. CONCLUSION: INF alpha-2b is less well tolerated than initially thought. Dosage was frequently decreased due to hematologic and hepatic toxicities. This could compromise the treatments efficacity. The minimal dose required to obtain an optimal response will thus have to be defined.  相似文献   
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Background: The use of electrocautery devices is associated with complications such as perforation or fistulisation when used near intestinal structures. This is likely due to its effect on vascularisation of the bowel wall. To test this hypothesis we established a murine model to quantify the effect of electrocautery injury on the intestinal microvascularisation.

Methods: Sprague-Dawley rats were subjected to five electrocautery injuries on the small bowel in coagulation mode (30 W intensity) and in cut mode (40 W, 80 W and 200 W intensities) for durations of 1, 2 and 5?s. 5?mg/kg of fluorescein was injected intravenously, the injured bowel segments harvested and the rat sacrificed. The segments were analysed to measure the fluorescence of injured bowel compared to adjacent unharmed tissue.

Results: A significant decrease in bowel wall microvascularisation occurred with increasing intensity (coag 30 W/cut 40 W versus cut 200 W 1?s: p?p?p?Conclusion: We successfully established a murine model to quantify the decrease of bowel wall microvascularisation associated with electrocautery use. Unsurprisingly, the decrease in microvascularisation is greater with higher intensity and duration of electrocautery and is associated with more perforations in the experimental model. The jejunum seems more vulnerable to electrocautery injury than the ileum. These observations support caution when using electrocautery devices near intestinal structures.  相似文献   
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OBJECTIVE—To describe the mode of presentation and the clinical course of patients with ventricular pre-excitation (Wolff-Parkinson-White (WPW) syndrome), with special emphasis on asymptomatic cases in the general population.
METHODS—Over an eight year period (1990-97) a prospective population based survey of cases with WPW pattern was conducted in a defined population in north west Greece (340 000 inhabitants). ECGs with WPW pattern were obtained from a widespread pool of ECGs within the health system.
RESULTS—During the study period, 157 cases with WPW pattern were identified (49 female, 108 male). Ages ranged from infants to 84 years, mean (SD) 49.1 (21.0) years in female and 39.6 (20.6) years in male subjects (p < 0.01); 78 (49%) had no history of syndrome related symptoms. Asymptomatic subjects (n = 77; 24 female, 53 male) were older than symptomatic subjects (mean age 46.7 (21.0) v 38.5 (20.6) years, p < 0.03). Documented supraventricular tachycardia was recorded in 27 patients (17%) and atrial fibrillation in 12 (8%) (mean age at first episode 31.2 (18.3) and 51.6 (20.7) years, respectively, p < 0.01). During follow up (mean 55 months) no case of sudden death occurred. Three asymptomatic subjects reported episodes of brief palpitation.
CONCLUSIONS—WPW pattern is more common, and diagnosed at a younger age, in men than in women. About half the patients with WPW pattern on ECG are asymptomatic at diagnosis and tend to remain so thereafter. No sudden cardiac death occurred during the study period.


Keywords: Wolff-Parkinson-White syndrome; epidemiology  相似文献   
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This paper aims at examining whether there is an association between the circadian patterns of systolic blood pressure, heart rate and the incidence of ventricular ectopic beats, as well as to confirm that reducing the blood pressure by a diuretic may also reduce the ectopic frequency. Thirty-four ambulatory patients with ventricular ectopic beats and a systolic blood pressure of 131.33 +/- 17.46 mmHg had a 24-hour Holter electrocardiographic and blood pressure monitoring following 1 week off any antiarrhythmic and antihypertensive treatment. Then they received for one week a standard diuretic combination (amiloride 5 mg + hydrochlorothiazide 50 mg) at a dose depending on their systolic pressure value and their monitoring was repeated. The mean hourly values of systolic blood pressure, heart rate and ventricular ectopic beats were "normalized", i.e. expressed as (x-x)/SD, taking each patient's 24-hour average as zero and his own standard deviation as the unit of measurement. As a group, there was an independent positive correlation between blood pressure and ectopic beats, while the heart rate was a nonsignificant negative factor for ectopic beats. On an individual level, however, an independent positive significant correlation between blood pressure and ectopic beats was found in only 8 cases, with a negative one in 4 cases. While the blood pressure of the group ranged symmetrically around its daily average value, the corresponding ectopic beat curve was highly asymmetric, with a very high incidence (up to 2.56 +/- 0.52 SD) for a rather short time (only 9.41 +/- 3.56 hours above average) and a low incidence (up to 1.26 +/- 0.49 SD) for the remaining 14.59 hours below average. Sudden rises in ectopic beat (greater than 1 SD/hour) occurred 1 to 6 times per day in each individual, significantly (P less than 0.01) more often (20.31%) with a high (greater than 1 SD) blood pressure than with a low (less than -1 SD) one (8.99%) with intermediate frequencies at intermediate pressures. After treatment with the diuretic, the systolic blood pressure was reduced, the heart rate increased and the ventricular ectopic beat incidence reduced (significant changes). The mean change in systolic pressure in 25 patients with a reduction in ectopy was a significant (P less than 0.01) decrease (-5.21 +/- 8.70 mmHg) while in the remaining 9 cases there was a non significant increase (+1.68 +/- 7.63 mmHg). The heart rate was higher in both subgroups.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
10.
The role of mitral annulus motion in left ventricular function.   总被引:4,自引:0,他引:4  
The dynamics between mitral annulus motion and left ventricular function were studied. Thirty subjects (10 normals, 10 with severe cardiac failure and 10 with mitral regurgitation) were examined. Left ventricular long and short-axis dimensions were measured in a two-dimensional apical four-chamber image. A volume was calculated as defined by cardiac cyclic changes of mitral annulus in size and motion. This volume had the approximate geometric configuration of a truncuated cone and was covered by mitral annulus motion at enddiastole and endsystole. Left ventricular ejection fraction was calculated echocardiographically using the prolate ellipsoid/area-length method. The volume defined by mitral annulus motion was 24 ml in normals, 16 ml in patients with cardiac failure and 48 ml in patients with mitral regurgitation while the ejection fraction was 51%, 19% and 53% respectively. Comparison between the volume of the truncuated cone and the ejection fraction in all 30 subjects revealed a statistically significant correlation (p less than 0.01). Thus, the bigger the volume determined by the mitral annulus motion during systole, the larger portion of the left ventricle is "atrialized", and a higher ejection fraction follows. Mitral annulus motion may provide new information about cardiac mechanics in normal and abnormal conditions.  相似文献   
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