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31.
Current clinical practice states that a urine culture yielding three or more isolates must be considered a contaminated specimen and discarded. The validity of this practice was tested by reviewing all patients at the West Haven Veterans Administration Hospital with positive blood cultures for 1 year to determine how many were associated with polymicrobic bacteriuria (two or more urine isolates each present at greater than 10(5) colonies/ml). During 1973 there were 18 patients who had bacteremia associated with a urinary tract infection in which the same organism with the identical antibiogram was found in both the blood and the urine of these 18 patients with monomicrobic bacteremia 11(61%) had polymicrobic bacteriuria, with a mean of an additional 1.75 urinary pathogens present in significant quantities. In these patients with polymicrobic bacteriuria, an indwelling bladder catheter was present for a mean period of 4.4 months before the episode of bacteremia. Only 5 of the 11 patients with polymicrobic bacteriuria had temporally associated urinary tract manipulation. Monomicrobic bacteriuria occurred in seven patients (39%). The mean indwelling bladder catheter time was 0.9 days, and urinary tract manipulation near the time of bacteremia occurred in all seven patients. Prospectively, nine other patients with polymicrobic bacteriuria were recultured by one of us to be certain that appropriate collection and transportation methods were used; the presence of polymicrobic bacteriuria was repeatedly demonstrated in 7(78%). This study illustrates the clinical importance of polymicrobic bacteriuria. 相似文献
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Altucher K Rasmussen KM Barden EM Habicht JP 《Journal of the American Dietetic Association》2005,105(5):709-715
OBJECTIVE: Nutrition supplementation programs are generally targeted to those members of the population who are thought to be at risk of an undesirable outcome, but not all who participate in such programs respond to them. We sought to identify determinants of improvement in hemoglobin concentration among young children in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). DESIGN: We conducted an observational study using data from 9,930 children who were enrolled in the Massachusetts WIC program and had data available on their hemoglobin values at both 1 and 2 years of age. Predictors of change in hemoglobin concentration between these ages were studied using multivariate statistical modeling. RESULTS: Overall, hemoglobin concentrations increased from age 1 to 2 years in those who had been breastfed 25 or more weeks (P < .0001) and were female (P < .01), and decreased with increasing weight at 1 year of age (P < .001). The determinants of change in hemoglobin concentration differed from the determinants of hemoglobin concentration at age 1 year. CONCLUSIONS: The analytical approach used here could be extended to identify subgroups of WIC participants likely to improve in other outcomes. If current efforts to increase the duration of breastfeeding among WIC participants are successful, the importance of WIC in improving hemoglobin concentration among young children also will increase. 相似文献
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Barden N Shink E Labbé M Vacher R Rochford J Mocaër E 《Progress in neuro-psychopharmacology & biological psychiatry》2005,29(6):908-916
The aim of this study was to evaluate the efficacy of agomelatine (S 20098) to accelerate reversal of the neuroendocrinological, behavioural and cyclical changes seen in a transgenic mouse model of the neuroendocrine characteristics of depression. The effects of agomelatine were assessed in transgenic mice with low glucocorticoid receptor (GR) function, after acute stress or induced phase shift, and compared to desipramine and melatonin. Mice were injected 2 h before the onset of the dark period with agomelatine (10 mg/kg, i.p.), desipramine (10 mg/kg, i.p.), melatonin (10 mg/kg, i.p.) or vehicle (hydroxy-ethyl-cellulose (HEC) 1%) each day for 21 to 42 days. Agomelatine was effective in reversing the transgenic mouse behavioural changes noted in the Porsolt forced swim test as well as in the elevated plus maze. Both the number of open arm entries and the total time spent in open arms of the elevated plus maze is greatly increased in transgenic mice. The mean time spent in open arms is exquisitely sensitive to reversal by agomelatine and desipramine. Agomelatine also markedly accelerated readjustment of circadian cycles of temperature and activity following an induced phase shift. This action of agomelatine was superior to that of melatonin while desipramine was without effect. The accelerating effect of agomelatine was particularly notable if treatment was started 3 weeks prior to the induced phase shift. Agomelatine treatment did not cause any major change in corticosterone or adrenocorticotropic hormone (ACTH) concentrations nor in vasopressin (AVP), corticotropin-releasing hormone (CRH), GR and mineralocorticoid receptor (MR) mRNAs levels, which make it unlikely that the mechanism of agomelatine action is related to hypothalamic-pituitary-adrenocortical (HPA) axis changes. The present study shows that agomelatine displays some characteristics of antidepressant drug action in the transgenic mouse model, effects that could be partially related to its chronobiotic properties. 相似文献
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Discrimination of benign and malignant thyroid nodules by molecular profiling 总被引:14,自引:0,他引:14
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BACKGROUND: The evaluation of thyroid nodules by fine-needle aspiration has been the standard for almost 30 years, despite significant shortcomings in sensitivity and specificity. Recent data from our laboratory have suggested that molecular profiling permits the discrimination of specific types of thyroid nodules. These studies were undertaken to determine whether molecular profiling can discriminate between benign and malignant thyroid nodules with the necessary sensitivity and specificity required of a screening test. METHODS: Molecular profiles of 11 papillary thyroid carcinomas, 13 follicular variant of papillary thyroid carcinomas, 9 follicular thyroid carcinomas, and 26 benign tumors (follicular adenomas and hyperplastic nodules) were analyzed by oligonucleotide microarray analysis. A gene list was created based on 45 samples. Seventeen samples were then added to the analysis as unknowns. A hierarchical clustering analysis was performed on all 62 samples to examine the groups for potential differences and the ability of the gene list to distinguish tumor types. RESULTS: Cluster analysis of all 62 samples produced 2 distinct groups, 1 containing the carcinomas and 1 containing the benign lesions. The sensitivity for a diagnosis of cancer was 91.7% with a specificity of 96.2% (3 follicular variant of papillary thyroid carcinomas clustered with the benign lesions). The cancer gene profiles contained both known cancer-associated genes (MET, galectin-3) and previously unidentified genes. CONCLUSIONS: Molecular profiling readily distinguishes between benign and malignant thyroid tumors with excellent sensitivity and specificity. Elucidated genes may provide insight into the molecular pathogenesis of thyroid cancer. Gene profiling may significantly enhance the evaluation of thyroid nodules in the future. 相似文献
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Barden B Seel W Löer F Konermann H 《Zeitschrift für Orthop?die und ihre Grenzgebiete》2004,142(3):298-302
PURPOSE: A hollow cementless femoral stem has been developed to reduce intramedullary pressure and fat embolism during implantation. METHODS: In a prospective randomized clinical study, cementless hip stems (ALPHA-FIT) were implanted in 42 patients (24 women, 18 men, mean age: 65.9 years). In Group I (n=21) a solid standard stem was used. In Group II (n=21) a modified hollow stem was implanted with vertical and longitudinal communicating drill holes opening at the implant surface. During surgery the intramedullary pressure was measured by a cannula fixed distally. RESULTS: During stem insertion the mean pressure was 82 mmHg (minimum-maximum, 12-259 mmHg) for Group I and 27 mmHg (minimum-maximum, 0-48 mmHg) for Group II. This difference was statistically significant (t-test, p < 0.00076). The pressure measured in Group II was similar to the base pressure before opening of the intramedullary canal (mean 35 mmHg; minimum-maximum, 4-72 mmHg). In both groups higher pressures were found for opening of the canal, drilling with the smallest drill size and rasping. CONCLUSION: Using the hollow prosthesis, the intramedullary pressure could be reduced significantly. The higher pressures during preparation of the femoral canal need further research. 相似文献