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91.
A series of studies designed to define the requirement of normal infants for sulfur-containing amino acids (methionine, cystine) was conducted with formulas providing 3.0, 2.8, 2.6, 2.2 or 1.8 g of isolated soy protein per 100 kcal. The formulas were fed with or without a methionine supplement. Adequacy of the diet was determined by measurement of growth, serum chemical indices and nitrogen balance. Nitrogen balance demonstrated a beneficial effect of methionine supplementation only at the lowest protein concentration (1.8 g/100 kcal). However, measurement of weight gain and/or serum concentrations of urea nitrogen and albumin clearly showed a beneficial effect of methionine supplementation at protein concentrations of 2.2 and 2.6 g/100 kcal. Intakes of sulfur-containing amino acids of 435 and 495 mumol/100 kcal therefore appear inadequate. At higher intakes of protein (2.8 and 3.0 g/100 kcal) there was no beneficial effect of methionine supplementation. Possible exceptions were male infants provided with 3.0 g protein per 100 kcal, in whom weight gain between 8 and 56 d of age was significantly (P less than 0.05) greater with than without a methionine supplement. Based on intakes of sulfur-containing amino acids from the formula providing 2.8 g of isolated soy protein per 100 kcal without methionine supplementation, we conclude that for male infants older than 56 d the requirement for sulfur-containing amino acids is no more than 588 mumol/100 kcal when intake of methionine is 264 mumol/100 kcal. However, it seems possible that such intake fails to meet the requirement in male infants less than 56 d of age. For female infants, regardless of age, 533 mumol/100 of sulfur-containing amino acids per 100 kcal meet the requirement when intake of methionine is 239 mumol/100 kcal.  相似文献   
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Valves in the subclavian and internal jugular veins were studied in 100 autopsy cases (52 men and 48 women; range, 18 to 91 years old; mean, 67 years). In 87 cases, valves were present in all 4 veins, and in 13 cases, valves anatomically were absent from 16 veins, 9 of which were the left internal jugular vein. The average distance from the valve to the junction with the innominate vein was 1.7 cm for the subclavian vein and 0.3 cm for the internal jugular vein. Cuspid height averaged 0.9 cm. Valves were bicuspid in 347 (90%) and unicuspid in 39 (10%); unicuspid valves were more common in the internal jugular vein than in the subclavian vein. Catheter-induced trauma was observed in 4 cases and implied in 4 more. These findings may have important implications concerning the failure, in some cases, of closed-chest cardiac resuscitation to maintain forward blood flow at adequate pressure.  相似文献   
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Traditionally, neuropsychological deficits due to Sickle Cell Disease (SCD) have been understudied in adults. We have begun to suspect, however, that symptomatic and asymptomatic Cerebrovascular Events (CVE) may account for an alarming number of deficits in this population. In the current brief review, we critically evaluated the pediatric and adult literatures on the neurocognitive effects of SCD. We highlighted the studies that have been published on this topic and posit that early detection of CVE via neurocognitive testing, neuropsychiatric evaluations, and neuroimaging may significantly reduce adult cognitive and functional morbidities.  相似文献   
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The role of the anesthesia provider requires a high level of awareness and constant vigilance. Literature indicates, however, that the substance abuse rate in certified registered nurse anesthetists (CRNAs) and anesthesiologists has reached staggering levels. The literature also shows that there has been a change in which controlled drugs are being misused. It is imperative that perianesthesia nurses be aware of the current problem and take steps when indicated to protect both providers and patients. This article discusses the current trends of addiction in anesthesia providers, treatment, and reentry, as well as the role of the perianesthesia nurse in recognizing, reporting, and preventing substance abuse.  相似文献   
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OBJECTIVE: To determine physical activity patterns in chronic hemodialysis patients with a specific emphasis on the difference between dialysis and nondialysis days. Design A cross-sectional single-center study. SETTING: Vanderbilt University Outpatient Dialysis Unit. PATIENTS: Twenty current chronic hemodialysis patients: 10 male, 10 female; 15 black, 5 white; mean age, 50.1 +/- 9.9 years; height, 164.5 +/- 10.9 cm; weight, 82.5 +/- 15.4 kg; length on dialysis, 57.3 +/- 45.3 months. METHODS: Minute-by-minute physical activity was assessed over a 7-day period using a triaxial accelerometer, which consists of raw numbers or counts calculated by the 3 axes of the accelerometer (PA counts). PA counts were extrapolated on a daily and hourly basis. Physical functioning tests included: sit-to-stand, 6-minute walk, and 1-repetition maximal leg press exercise. Laboratory values for serum concentrations of albumin, prealbumin, C-reactive protein, and cholesterol were also collected. MAIN OUTCOME MEASURE: PA counts. RESULTS: Total PA counts were significantly lower on dialysis days when compared with nondialysis days (128,279 +/- 74,009 versus 168,744 +/- 95,168, respectively, P = .025). The average PA counts during the 4-hour dialysis time period were significantly lower on dialysis days when compared with nondialysis days (3,086 +/- 3,749 versus 11,070 +/- 7,695, respectively, P = .001). At postdialysis hours 1 and 2, PA counts on dialysis days were significantly higher than on nondialysis days (11,410 +/- 5,340 versus 9,082 +/- 6,646, P = .008, and 14,048 +/- 9,728 versus 8,662 +/- 6,433, P = .016, respectively). By postdialysis hour 4, PA counts on dialysis days had significantly decreased when compared with nondialysis days (6,068 +/- 6,268 versus 10,512 +/- 7,420 PA counts, P = .01, respectively). From postdialysis hours 5 to 20, there was no significant difference in PA counts between dialysis and nondialysis days. CONCLUSION: This study shows that physical activity is lower on dialysis days when compared with nondialysis days, and this decrease is caused by the lack of activity during the 4-hour hemodialysis procedure. New behavior modification strategies involving physical activity, both during hemodialysis and on nondialysis days, must be examined in this patient population.  相似文献   
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To identify risk factors for fractures in multi-ethnic women, we studied 159,579 women enrolled in the Women's Health Initiative. In general, risk factors for fractures were similar across ethnic groups. However, irrespective of their ethnicity, women with multiple risk factors have a high risk of fracture. Targeting these high-risk women for screening and intervention could reduce fractures. INTRODUCTION: Fracture rates tend to be lower in minority women, but consequences may be greater. In addition, the number of fractures is expected to increase in minority women because of current demographic trends. There are limited prospective data on risk factors for fractures in minority women. MATERIALS AND METHODS: We studied 159,579 women 50-79 yr of age enrolled in the Women's Health Initiative. Information on risk factors was obtained by questionnaire or examination. Nonspine fractures that occurred after study entry were identified over an average follow-up of 8 +/- 2.6 (SD) yr. RESULTS: Annualized rates (%) of fracture in whites, blacks, Hispanics, Asians, and American Indians were 2.0, 0.9, 1.3, 1.2, and 2.0, respectively. Significant predictors [HR (95% CI)] of fractures by ethnic group were as follows: blacks: at least a high school education, 1.22 (1.0, 1.5); (+) fracture history, 1.7 (1.4, 2.2); and more than two falls, 1.7 (1.9, 2.0); Hispanics: height (>162 cm), 1.6 (1.1, 2.2); (+) fracture history, 1.9 (1.4, 2.5); more than two falls, 1.8 (1.4, 2.3); arthritis, 1.3 (1.1, 1.6); corticosteroid use, 3.9 (1.9, 8.0); and parental history of fracture, 1.3 (1.0, 1.6); Asians: age (per 5 yr), 1.2 (1.0, 1.3); (+) fracture history, 1.5 (1.1, 2.0); current hormone therapy (HT), 0.7 (0.5, 0.8); parity (at least five), 1.8 (1.1, 3.0); more than two falls, 1.4 (1.1, 1.9); American Indian: (+) fracture history, 2. 9 (1.5, 5.7); current HT, 0.5 (0.3, 0.9). Women with eight or more risk factors had more than a 2-fold higher rate of fracture compared with women with four or fewer risk factors. Two ethnicity x risk factor interactions were identified: age and fall history. CONCLUSIONS: Irrespective of their ethnicity, women with multiple risk factors have a high risk of fracture. Targeting these high-risk women for screening and intervention could reduce fractures.  相似文献   
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