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排序方式: 共有315条查询结果,搜索用时 288 毫秒
31.
Purpose: The purpose of this study was to evaluate whether asthenopic symptoms in schoolchildren diagnosed with accommodative insufficiency (AI) and graded with the Visual Analogue Scale (VAS) could be correlated with the degree of accommodative deficiency in these children, and to investigate if VAS grading of the asthenopic symptoms could be used as an instrument to indicate the level of improvement of AI. Methods: Forty-nine children (mean age 10.2 years ± 2.7) diagnosed with AI graded their degree of asthenopia on the VAS before and after a 12-week treatment period wearing individually dispensed reading glasses. Results: The improvement in accommodation after treatment was statistically significant (p < 0.001) and 83.7% of the children obtained normal accommodative amplitude in relation to age. The reduction in asthenopic symptoms as graded with the VAS was also statistically significant (p < 0.001) after treatment and 89.9% of the children obtained a normal VAS score. However, no correlation between the degree of accommodative deficiency and the VAS grading could be found, neither before nor after treatment. Discussion: Based on these results we conclude that the visual analogue scale (VAS) cannot be used as an instrument to indicate the degree of accommodative deficiency nor can it be used to indicate the level of improvement during the course of treatment. However, the VAS can be used as an instrument to verify and document whether or not asthenopic symptoms are present, and therefore also to indicate when symptoms have been relieved. 相似文献
32.
Annika Rydberg Dag E. Teien Peter Rask Rolf Hrnsten 《Clinical physiology and functional imaging》2000,20(1):69-78
Despite successful operation, many patients palliated with a Fontan‐type procedure continue to show effort limitation. We previously observed that these children showed electrocardiographic ST depression during exercise tests. The purpose of the study was to investigate whether electrocardiographic ST depression is a common finding in children with Fontan circulation. Forty‐two children in two groups were examined: group A consisted of 14 patients who had all undergone a modified Fontan procedure, and group B consisted of 28 children with a structurally normal heart, matched for length, weight and gender to group A. Complete echocardiographic examinations were performed in all patients and controls. All 14 patients and all 28 healthy children underwent standard 24 h ambulatory electrocardiographic monitoring. All the recordings were analysed by a PC‐based Holter system where an analysis of ST changes was performed. Seven patients and 14 matched healthy children were exercised on bicycle ergometers. Four patients and eight matched healthy children underwent exercise testing by walking/running a treadmill. Ten of 13 patients analysed had significant ST depressions on ambulatory electrocardiogram (>0·20 mV). Three of the 10 patients with ST depression were on digoxin. Three patients showed depressions of the ST segment in the electrocardiogram during exercise, with a maximal depression of 0·20–0·35 mV. None of the 28 matched healthy children showed electrocardiographic ST depression on the ambulatory 24 h ECG. These findings indicate that ST depression in daily activity is a common finding in children with Fontan circulation. 相似文献
33.
Purpose: To examine the accommodative amplitude and convergence in 10-year-old prematurely born children previously screened for retinopathy of prematurity (ROP) and to compare with full-term controls of the same age. Methods: Two-hundred and thirteen prematurely born and 217 children born at term were included. Accommodative amplitude and near-point convergence were assessed, together with best-corrected visual acuity (VA). A questionnaire was answered regarding possible problems at school. Results: Binocular accommodation (P = 0.03) and convergence (P = 0.003) were significantly poorer in prematurely born children. Accommodation was correlated to neurological findings in the preterm group, but not to the degree of prematurity or stage of ROP. Regarding convergence there were no correlations to neurology, stage of ROP, or degree of prematurity. For neither accommodation nor convergence were any correlations with distance and near VA found. Preterm children had a higher prevalence of school problems, and there was an association with poor accommodation. Conclusions: Prematurely born children had poorer accommodation and convergence than full-term children, but no association with near VA was found. The reduction of accommodative amplitude and convergence was small and was probably of little clinical significance. However, it may have additional effects on other ophthalmological problems and school problems in the preterm group. 相似文献
34.
Marie Pedersen Hans von Stedingk Maria Botsivali Silvia Agramunt Jan Alexander Gunnar Brunborg Leda Chatzi Sarah Fleming Eleni Fthenou Berit Granum Kristine B. Gutzkow Laura J. Hardie Lisbeth E. Knudsen Soterios A. Kyrtopoulos Michelle A. Mendez Domenico F. Merlo Jeanette K. Nielsen Per Rydberg Dan Segerb?ck Jordi Sunyer John Wright Margareta T?rnqvist Jos C. Kleinjans Manolis Kogevinas the NewGeneris Consortium 《Environmental health perspectives》2012,120(12):1739-1745
35.
Autonomic nervous control of the heart can be studied by analysing variability in heart rate. Although earlier studies have shown reduced variability in patients with the Fontan circulation, we are not aware of any previous study examining longitudinal changes in such children. We have examined 13 patients who had undergone total cavopulmonary connection, and 37 healthy controls matched for age and gender. The examinations included complete echocardiography, and 24-hour ambulatory electrocardiogram for analysis of the parameters for variability in heart rate. After the Fontan procedure, three follow-up examinations were performed at a mean of 4.4 years, 5.6 and 7.2 years. Reduced variability was found in those with the Fontan circulation. A significant difference was found between patients and their controls with respect to high-frequency power at the second, p equal to 0.05, and third, p equal to 0.03, examination. The ratio of low-to-high-frequency components progressively increased in those with the Fontan circulation, a phenomenon that led to a significant difference, p equal to 0.03, at the third examination. Our study shows that, in patients with the Fontan circulation, routine ambulatory electrocardiographic monitoring including analysis of variability in heart rate, detects over time a progressive sympatovagal imbalance. 相似文献
36.
37.
Lennart Rydberg Michael E. Breimer Kurt Nilsson Lola Svensson Bo E. Samuelsson Egidio Romano 《Xenotransplantation》1998,5(2):105-110
ABSTRACT: A quantitative ELISA technique for determination of human anti-pig xenoantibody number in serum samples has been established using pig lymphocytes and pig/rabbit erythrocytes as target cells and a pool of serum from human blood group AB donors. The number of low affinity antibodies binding to the cells was determined by quantitation following the use of aqueous washing of the cells and separation of bound and unbound antibodies with the phthalate oil method. The efficiency of different soluble Galal-3Gal-terminating di- and tri-saccharides to inhibit antibody binding was tested and found to vary between 70–90% at a saccharide concentration of 10 mg/ml. The assay was used to evaluate the antibody changes in two patients who, after plasmapheresis treatments, had pig kidneys extracorporeally connected to their blood circulation. The number of anti-pig IgM/IgG antibodies bound to each pig lymphocyte were reduced from 5,600/13,200 to 1,300/3,100 in patient 1 and from 1,200/6,500 to 500/2,100 in patient 2 by three consecutive daily plasmapheresis treatments. Although the lymphocytotoxic titers were reduced to very low levels, the antibody numbers still present in the blood of patient 1 caused a hyperacute rejection of the pig kidney. However, the antibody levels in patient 2 did not cause rejection of this kidney during 15 min perfusion time. A strong anti-pig antibody response 3 weeks after the perfusion experiment was found in patient 1 as shown by 27,600/245,300 IgM/IgG molecules bound to pig lymphocytes corresponding to an increase of lymphocytotoxic titer from 8 to 512. The second patient showed a much weaker immune response with 1,400/19,800 IgM/IgG antibodies corresponding to a lymphocytotoxic titer increase from 8 to 32. The use of this quantitation technique enables more accurate investigation of antibody bindine to xenoeenic tareet cells than conventional titration techniaues. 相似文献
38.
Problems associated with posterior lumbar interbody fusion (PLIF) have traditionally included the need for donor bone, prolonged healing time of donor bone, the difficulty of cutting precise bony channels, the risk of retropulsion of graft, postoperative collapse of the bone graft, and pseudarthrosis. To avoid these problems a carbon fiber reinforced polymer implant cage has been developed to facilitate interbody fusion. The aim of the present study was to evaluate the technical problems and fusion rate associated with this new device for PLIF. Between April 1991 and December 1993, 65 pairs of these implant cages were sold in Sweden. They were traced to six hospitals, where they had been used in the treatment of 51 patients operated on at a total of 65 levels. All PLIF were supplemented with VSP (Variable Screw Placement) instrumentation. All medical records were evaluated and all patients were examined with plain radiographs taken at least 1 year after surgery. If that investigation did not show a clear fusion they were also evaluated with CT (18 patients, 27 levels). No intraoperative problems with the device have been reported; 44 patients (86%) and 58 levels (89%) achieved successful fusion. All patients bar one maintained their immediately obtained postoperative disc height. CT with 1-mm slices and sagittal reconstruction is most helpful if radiographs are difficult to interpret. 相似文献
39.
40.
Abstract: Using male Sprague-Dawley rats of different ages, simple motor activity was measured over three 4 min. runs in a square open field after ethanol (EtOH, 2 g/kg, intraperitoneally) or saline. The different groups consisted of 12 animals whose mean ages was 20, 40 and 60 days. Motor activity and blood ethanol levels were measured at 30, 60 and 120 min. after injection. Blood ethanol levels (measured after each run) decreased from 1st to 3rd run in 20 and 40 day groups and increased from 1st to 2nd run in the 60 day group, before decreasing. Activity data indicated: 1) decrease in motor activity the 3 runs by all saline and the 21 day EtOH groups, 2) initial lower activity induced by EtOH in all age groups, 3) lack of decrease in activity over 3 runs in 40 and 60 day EtOH groups. All saline and EtOH age groups showed within-run decrease of activity 相似文献