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991.
Rouweyha RM Chuang AZ Mitra S Phillips CB Yee RW 《Journal of refractive surgery (Thorofare, N.J. : 1995)》2002,18(3):217-224
PURPOSE: To describe the refractive outcome, objective clinical data, and subjective patient experiences after laser epithelial keratomileusis (LASEK) at 1, 3, and 6 months after surgery. METHODS: This was a retrospective, nonrandomized, comparative study of 58 LASEK-treated eyes (36 patients) with myopia (with and without astigmatism) between -1.50 and -14.75 D (mean -7.80 +/- 2.90 D, median -7.90 D). Refractive surgery was performed using the Alcon Summit Autonomous LADAR Vision excimer laser. Manifest refraction, best-spectacle and uncorrected Snellen visual acuity, stability of refraction, and corneal haze were evaluated before surgery and up to 6 months after surgery. A group of randomly selected LASIK-treated eyes were compared at each time point. RESULTS: Patients who opted for monovision (n=12) were excluded. In the emmetropia targeted eyes (n=46), 45%, 83%, 85%, and 89% achieved 20/40 or better uncorrected Snellen visual acuity (UCVA) at 1 day, 1 week, 2 weeks, and 1 month respectively. At 6 months, 73% (n=28) of eyes treated achieved UCVA 20/20 with 97% achieving 20/40 or better (mean, -0.51 D). At 3 and 6 months, 71% (n=46) and 68% (n=28) were within +/- 0.50 D of emmetropia. The percentage of eyes that achieved UCVA 20/40 or better at 6 months was 97% (n=28). Visually significant corneal haze was evident in two LASEK-treated patients (four eyes) at 6 months. No eyes lost two or more lines of best spectacle-corrected Snellen visual acuity. CONCLUSIONS: Preliminary data suggest that LASEK appears to be a safe, effective, and comparable alternative to LASIK, even for higher amounts of myopia. A prospective, randomized clinical trial is needed to better define the role of LASEK as it compares to other refractive procedures, specifically LASIK and PRK. 相似文献
992.
Using machine learning classifiers to identify glaucomatous change earlier in standard visual fields
Sample PA Goldbaum MH Chan K Boden C Lee TW Vasile C Boehm AG Sejnowski T Johnson CA Weinreb RN 《Investigative ophthalmology & visual science》2002,43(8):2660-2665
PURPOSE: To compare the ability of several machine learning classifiers to predict development of abnormal fields at follow-up in ocular hypertensive (OHT) eyes that had normal visual fields in baseline examination. METHODS: The visual fields of 114 eyes of 114 patients with OHT with four or more visual field tests with standard automated perimetry over three or more years and for whom stereophotographs were available were assessed. The mean (+/-SD) number of visual field tests was 7.89 +/- 3.04. The mean number of years covered (+/-SD) was 5.92 +/- 2.34 (range, 2.81-11.77). Fields were classified as normal or abnormal based on Statpac-like methods (Humphrey Instruments, Dublin, CA) and by several machine learning classifiers. The machine learning classifiers were two types of support vector machine (SVM), a mixture of Gaussian (MoG) classifier, a constrained MoG, and a mixture of generalized Gaussian (MGG). Specificity was set to 96% for all classifiers, using data from 94 normal eyes evaluated longitudinally. Specificity cutoffs required confirmation of abnormality. RESULTS: Thirty-two percent (36/114) of the eyes converted to abnormal fields during follow-up based on the Statpac-like methods. All 36 were identified by at least one machine classifier. In nearly all cases, the machine learning classifiers predicted the confirmed abnormality, on average, 3.92 +/- 0.55 years earlier than traditional Statpac-like methods. CONCLUSIONS: Machine learning classifiers can learn complex patterns and trends in data and adapt to create a decision surface without the constraints imposed by statistical classifiers. This adaptation allowed the machine learning classifiers to identify abnormality in visual field converts much earlier than the traditional methods. 相似文献
993.
Drugs and diseases have differential effects on functional and structural components of large-conduit arteries and smaller vessels. The objective of this study was to demonstrate functional and structural effects of doxazosin (DOX) on largevessel and small-vessel arterial elasticity in hypertension (HTN). This was an open-label, single-blind, active-therapy study. Patients with stage 1 to 2 HTN were administered DOX 2 mg/day for 3 months and 4 mg/day for 1 month, if indicated, followed by 2-week washout period. Arterial elasticity was measured noninvasively at baseline, at 3 months and 4 months of treatment, and 2 weeks following DOX withdrawal. Although the observed effects were not statistically significant, large-vessel elasticity (C1) increased in a dose-related manner and returned to baseline 2 weeks after drug withdrawal. There was a trend toward an increase in small-vessel elasticity in a dose-related manner. However, 2 weeks after drug withdrawal, C2 (distal elasticity) had not returned to baseline and was statistically significantly different from baseline (p = 0.032). It was concluded that large-artery compliance increased in a dose-related manner. Almost all benefit was lost within 2 weeks of discontinuation, suggesting the DOX effect was functional. Small-artery compliance improved in a dose-related manner but only partially returned to baseline after DOX withdrawal, suggesting changes in artery structure by DOX. 相似文献
994.
A survey of acute trusts' nurse cadet schemes in England showed a wide variety in entry requirements and qualifications offered. Most schemes offered successful students a place on a nurse training scheme. Legal issues surrounding 16-year-olds working in hospitals need to be clarified. Standardisation of entry requirements and course qualifications is required. At present, a student could complete a cadet course in one part of the country and not be eligible for nurse training elsewhere. 相似文献
995.
Stevens C 《The Health service journal》2002,112(5787):27
996.
Deeming C 《The Health service journal》2002,112(5819):28-29
Hospital meals cost the NHS, on average, 2.50 Pounds per patient per day. Costs are higher in hospitals which prepare food on site, specialist trusts and those in London. The Wanless report has proposed that expenditure should rise to 4.80 Pounds per patient per day, at today's prices, by 2022. More effort should go into cutting food wastage which currently costs hospitals in England more than 18 m Pounds a year. 相似文献
997.
Green tea consumption and serum lipids and lipoproteins in a population of healthy workers in Japan 总被引:9,自引:0,他引:9
Tokunaga S White IR Frost C Tanaka K Kono S Tokudome S Akamatsu T Moriyama T Zakouji H 《Annals of epidemiology》2002,12(3):157-165
PURPOSE: To examine the relation between green tea consumption and serum lipids and lipoproteins. METHODS: The subjects were 13,916 workers (8476 men and 5440 women) aged 40-69 years at over 1000 workplaces in Nagano prefecture, central Japan. They underwent health screening offered by a single medical institute between April 1995 and March 1996 and did not have morbid conditions affecting serum cholesterol levels. Serum concentrations of total cholesterol, high-density lipoprotein (HDL) cholesterol and triglycerides were measured at the screening. The consumption of green tea and other life-style characteristics were ascertained by a questionnaire. The data were analyzed with multivariate linear model. RESULTS: Daily consumption of green tea was reported by 86.7% of subjects. Green tea consumption was, statistically, significantly associated with lower levels of serum total cholesterol in both men and women while its associations with serum triglycerides and HDL cholesterol were not statistically significant. The inverse association of serum total cholesterol with green tea consumption appeared to level off at the consumption of more than 10 cups/day. Excluding the outlying subjects drinking more than 10 cups/day (0.4%), the regression analysis adjusting for age, body mass index, ethanol intake, smoking habit, coffee intake, and type of work showed that daily consumption of one cup of green tea was associated with a reduction in serum total cholesterol by 0.015 mmol/L (95% confidence interval 0.006 to 0.024, p < 0.001) in men and 0.015 mmol/L (0.004 to 0.025, p < 0.01) in women. After additional adjustment for selected dietary factors, the inverse association remained statistically significant; one cup of green tea per day was associated with a reduction in serum total cholesterol by 0.010 mmol/L (0.001 to 0.019, p = 0.03) in men and 0.012 mmol/L (0.001 to 0.022, p = 0.03) in women. CONCLUSION: Consumption of green tea was associated with lower serum concentration of total cholesterol in Japanese healthy workers age 40-69 years; however, green tea consumption was unrelated to serum HDL-cholesterol and triglycerides. 相似文献
998.
Holm S Toma RB Reiboldt W Newcomer C Calicchia M 《International journal of food sciences and nutrition》2002,53(4):337-342
This study investigates the efficacy of a 62 h cleaning frequency in the manufacturing of ice-cream. Various product and product contact surfaces were sampled progressively throughout the time period between cleaning cycles, and analyzed for microbial growth. The coliform and standard plate counts (SPC) of these samples did not vary significantly over time after 0, 24, 48, or 62 h from Cleaning in Place (CiP). Data for product contact surfaces were significant for the SPC representing sample locations. Some of the variables in cleaning practices had significant influence on microbial loads. An increase in the number of flavors manufactured caused a decrease in SPC within the 24 h interval, but by the 48 h interval the SPC increased. More washouts within the first 24 h interval were favorable, as indicated by decreased SPC. The more frequently the liquefier was sanitized within the 62 h interval, the lower the SPC. This study indicates that food safety was not compromised and safety practices were effectively implemented throughout the process. 相似文献
999.
The purpose of this study was to assess the agreement between the 24 h diet recall and a short 17-item 24 h food intake recall in assessing calcium intake. The calcium intakes of 21 women over the age of 50 were assessed by both methods on four occasions. The mean calcium intakes were similar using both methods, being 1034+/-398 mg/day by 24 h diet recall and 822+/-412 mg/day (SD) by 17-item 24 h food intake recall. The 17-item 24 h food intake recall tended to underestimate calcium intake compared with the 24 h diet recall, with the limits of agreement being between -1197 and -727 below and 370 and 682 mg/day above 24 h diet recall values over the four assessments. The 17-item 24 h food intake recall identified 8% more women with inadequate calcium intakes than the 24 h diet recall method did. Although there is poor agreement in calcium intake between the 24 h diet recall method and the 17-item 24 h food intake recall, the latter provides a quick and simple means for assessing extremes of calcium intake and whether day to day calcium intake is adequate. 相似文献
1000.
Serb C 《Hospitals & health networks / AHA》2002,76(5):44-7, 2
This installment of our quarterly series on clinical management issues focuses on trends in oncology services. Even with the threat of overbuilding in certain markets, proposed cuts to Medicare reimbursements and competition from niche facilities, hospitals are placing renewed emphasis--and spending--on cancer. 相似文献