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31.
The relationship between methylxanthine intake (caffeine, theobromine and theophylline) and risk of benign proliferative epithelial disorders (BPED) of the breast was examined in a case-control study conducted in Adelaide, South Australia. The study involved 383 cases with biopsy-confirmed BPED, 192 controls whose biopsy did not show epithelial proliferation, and 383 unbiopsied community controls individually matched to cases on age and area of residence. Overall, there was relatively little variation in risk of BPED with total methylxanthine intake, or with intake of caffeine or theophylline, while there was a positive association between theobromine intake and risk of BPED, but only when cases were compared with biopsy controls. Total methylxanthine intake was positively associated with risk of BPED showing severe atypia, but the trend in risk was statistically significant only when community controls formed the comparison group. These data do not provide strong support for an association between methylxanthine intake and risk of BPED. 相似文献
32.
33.
Long-term precision of 18F-fluoride PET skeletal kinetic studies in the assessment of bone metabolism. 总被引:1,自引:0,他引:1
Michelle L Frost Glen M Blake So-Jin Park-Holohan Gary J R Cook Kathleen M Curran Paul K Marsden Ignac Fogelman 《Journal of nuclear medicine》2008,49(5):700-707
(18)F-Fluoride PET allows noninvasive evaluation of regional bone metabolism and has the potential to become a useful tool for assessing patients with metabolic bone disease and evaluating novel drugs being developed for these diseases. The main PET parameter of interest, termed K(i), reflects regional bone metabolism. The aim of this study was to compare the long-term precision of (18)F-fluoride PET with that of biochemical markers of bone turnover assessed over 6 mo. METHODS: Sixteen postmenopausal women with osteoporosis or significant osteopenia and a mean age of 64 y underwent (18)F-fluoride PET of the lumbar spine and measurements of biochemical markers of bone formation (bone-specific alkaline phosphatase and osteocalcin) and bone resorption (urinary deoxypyridinoline) at baseline and 6 mo later. Four different methods for analyzing the (18)F-fluoride PET data were compared: a 4k 3-compartmental model using nonlinear regression analysis (K(i-4k)), a 3k 3-compartmental model using nonlinear regression analysis (K(i-3k)), Patlak analysis (K(i-PAT)), and standardized uptake values. RESULTS: With the exception of a small but significant decrease in K(i-3k) at 6 mo, there were no significant differences between the baseline and 6-mo values for the PET parameters or biochemical markers. The long-term precision, expressed as the coefficient of variation (with 95% confidence interval in parentheses), was 12.2% (9%-19%), 13.8% (10%-22%), 14.4% (11%-22%), and 26.6% (19%-40%) for K(i-3k), K(i-PAT), mean standardized uptake value, and K(i-4k), respectively. For comparison, the precision of the biochemical markers was 10% (7%-15%), 18% (13%-27%), and 14% (10%-21%) for bone-specific alkaline phosphatase, osteocalcin, and urinary deoxypyridinoline, respectively. Intraclass correlation between the baseline and 6-mo values ranged from 0.44 for K(i-4k) to 0.85 for K(i-3k). No significant correlation was found between the repeated mean standardized uptake value measurements. CONCLUSION: The precision and intraclass correlation observed for K(i-3k) and K(i-PAT) was equivalent to that observed for biochemical markers. This study provided initial data on the long-term precision of (18)F-fluoride PET measured at the lumbar spine, which will aid in the accurate interpretation of changes in regional bone metabolism in response to treatment. 相似文献
34.
Mohamad H Yamani Daniel J Cook E Murat Tuzcu Philip Paul Norman B Ratliff Yang Yu Robert Hobbs Gustavo Rincon Corinne Bott-Silverman Nicholas Smedira James B Young Randall C Starling 《The Journal of heart and lung transplantation》2005,24(8):1014-1018
BACKGROUND: Recipients of hearts from donors with spontaneous intracerebral hemorrhage (ICH) are at increased risk of allograft vasculopathy compared with trauma donors. We have recently shown that the vitronectin receptor (integrin alpha(V)beta3) is upregulated in transplant vasculopathy. We hypothesized that donor ICH is associated with systemic activation of alpha(V)beta3 in the donor before transplantation. METHODS: We evaluated mRNA expressions of alpha(V)beta3 (TaqMan PCR) in endomyocardial biopsy samples at 1-week post-transplant in 20 recipients from ICH donors and 20 recipients from trauma donors. To investigate whether systemic activation of alpha(V)beta3 was present in the donor before transplantation, alpha(V)beta3 expression was also evaluated in the corresponding donor spleen lymphocytes. All patients underwent serial coronary intravascular ultrasound to evaluate for coronary vasculopathy. The baseline characteristics were similar except for increased donor age in the ICH Group. RESULTS: The ICH Group showed significant increased mRNA expression of alpha(V)beta3 in the heart biopsy samples (3.8-fold, p = 0.012) and in the corresponding donor spleen lymphocytes (3.5-fold, p = 0.014) compared with the Trauma Group. At 1 year, the ICH Group also showed increased progression of coronary vasculopathy. Multivariate regression analysis found that donor lymphocytic alpha(V)beta3 mRNA expression was independently associated with increased risk of vasculopathy (odds ratio, 1.9; 95% CI, 1.21-3.98, p = 0.03). CONCLUSIONS: Our report demonstrates the presence of systemic activation of alpha(V)beta3 in donors with spontaneous intracerebral hemorrhage and its association with the subsequent development of allograft vasculopathy in the recipient. 相似文献
35.
L Vadlamudi R Hatton K Byth J Harasty S Vogrin M J Cook A F Bleasel 《Journal of clinical neuroscience》2006,13(2):206-213
Planum temporale volumes were determined for 42 control children (ages 4.2-15.7 years) using magnetic resonance imaging. The mean left planum temporale volume was 2729 mm3 (SD = 567) and the mean right planum temporale volume was 2758 mm3 (SD = 546). No significant hemispheric asymmetry was demonstrated. Analysis of co-variance (ANCOVA) showed that the absolute and proportional planum temporale volumes were not significantly associated with age or gender. We also demonstrated a reproducible method for planum temporale volume measurement by acquiring images in the coronal plane and then visualising the sagittal plane to improve accuracy for the posterior border. 相似文献
36.
Kevin O'Brien Jean Wright Frances Conboy YeWeng Sanjie Nicky Mandall Stephen Chadwick Ivan Connolly Paul Cook David Birnie Mark Hammond Nigel Harradine David Lewis Cathy McDade Laura Mitchell Alison Murray Julian O'Neill Mike Read Stephen Robinson Dai Roberts-Harry Jonathan Sandler Ian Shaw 《American journal of orthodontics and dentofacial orthopedics》2003,124(3):234-43; quiz 339
This study evaluated the effectiveness of early orthodontic treatment with the Twin-block appliance for the developing Class II Division 1 malocclusion. This multicenter trial was carried out in the United Kingdom. A total of 174 children, aged 8 to 10 years old, with Class II Division 1 malocclusion were randomly allocated to receive treatment with a Twin-block appliance or to an untreated, control group. Data were collected at the start of the study and 15 months later. Results showed that early treatment with Twin-block appliances resulted in reduction of overjet, correction of molar relationships, and reduction in severity of malocclusion. Most of this correction was due to dentoalveolar change, but some was due to favorable skeletal change. Early treatment with the Twin-block appliance is effective in reducing overjet and severity of malocclusion. The small change in the skeletal relationship might not be considered clinically significant. 相似文献
37.
Improved survival rates for patients with major burn injuries and the consistent finding of significant long-term psychologic disability among survivors of burn trauma call for a redefinition of the role of the psychiatric consultant in the care of patients with burns. In addition to the traditional functions of diagnosis and treatment of discrete psychiatric disorders in patients with burns, this expanded role includes assisting the patient's normal process of psychologic adaptation after injury, assessing and managing burn pain, and facilitating communication among all members of the burn team. The functions of the psychiatrist are most effectively carried out when the psychiatrist is able to participate on a regular basis in the care of every patient as a member of the burn team. 相似文献
38.
A N Phillips J D Neaton D G Cook R H Grimm A G Shaper 《American journal of epidemiology》1992,136(1):59-70
The association between leukocyte count and subsequent risk of major coronary heart disease events was examined using data from three prospective cohort studies--two from the United States and one from Great Britain. A total of 28,181 middle-aged men were followed for 6-12 years. A total of 1,768 men had a nonfatal myocardial infarction or died of coronary heart disease. In all three cohorts, there was a positive, statistically significant relation between baseline leukocyte count and risk of subsequent major coronary heart disease events after adjustment for age, serum total cholesterol, diastolic blood pressure, and number of cigarettes smoked per day (relative odds = 1.32 (p less than 0.0001), 1.15 (p = 0.0001), and 1.14 (p = 0.003), corresponding to a 2,000/mm3 difference in leukocyte count). The associations persisted when all nonsmokers (former smokers plus never smokers) and never smokers alone were considered and when those with evidence of preexisting coronary heart disease at baseline were excluded. Leukocyte count appears to be an indicator of a person's future risk of major coronary heart disease events. 相似文献
39.
Changes in temporal gait characteristics and pressure distribution for bare feet versus various heel heights 总被引:8,自引:0,他引:8
The purpose of this study was to identify changes in temporal gait characteristics and pressure generation across the sole of the foot due to various heel heights in women's dress pumps. Thirty female subjects, aged 18-30 years, volunteered to participate. Subjects were required to have normal gait and to wear comfortably either size 7 or size 9 shoes. Subjects were tested initially in bare feet using electrodynography (Langer Biomechanics Group, 21 East Industry Court, Deer Park, NY 11729-9986) (EDG) at a cadence of ~100 steps/min set by metronome. EDG trials with 4 pairs of shoes were then performed in random order. Shoes were women's dress pumps identical except for heel height. Heel heights were 1.75, 3.12, 5.72 and 8.74 cm. Data were collected over ~ 30 steps and averaged over this period. Data were analyzed using a one-way ANOVA, and changes were only considered significant if the ANOVA identified significant variations bilaterally. Considering temporal gait variables, we concluded that: (1) stance phase was shortened in shoes vs. bare feet but was unaffected by heel height, (2) the percentage of stance spent in weight bearing on the lateral and medial calcaneus decreased above a 3.12 cm heel height, (3) the percentage of stance spent in weight bearing on the first and second metatarsal heads increased in shoes vs. bare feet but was unaffected by heel height, (4) the percentage of stance spent in weight bearing on the fifth metatarsal was less in the 8.74 cm heel than in any other shoe or in bare feet. With regard to pressure variables, we found that: (1) peak pressure under the fifth metatarsal head was inversely related to heel height, (2) pressure under the third metatarsal head peaked earliest in heels greater than 5.72 cm high, and (3) pressure under the medial calcaneus peaked latest in heels greater than 5.72 cm high. 相似文献
40.