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101.
Background: Despite the availability of international nutrition recommendations, preterm infants remain vulnerable to suboptimal nutrition. The standard approach of assessing nutrient intakes chronologically may make it difficult to identify the origin of nutrient deficits and/or excesses. Objective: To develop a “nutrition phase” approach to evaluating nutrition support, enabling analysis of nutrient intakes during the period of weaning from parenteral nutrition (PN) to enteral nutrition (EN), called the transition (TN) phase, and compare the data with those analyzed using the standard “chronological age” approach to assess whether the identification of nutrient deficits and/or excesses can be improved. Methods: Analysis of a comprehensive nutrition database developed using actual nutrient intake data collected on an hourly basis in 59 preterm infants (birth weight ≤1500 g, gestation <34 weeks) over the period of PN delivery (range, 2–21 days). Results: The nutrition phase analysis approach revealed substantial macronutrient and energy deficits during the TN phase. In particular, deficits were identified as maximal during the EN‐dominant TN phase (enteral feeds ≥80 mL/kg/d) of the infant’s nutrition course. In contrast, the chronological age analysis approach did not reveal a corresponding pattern of deficit occurrence but rather intakes that approximated or exceeded recommendations. Conclusion: Actual intakes of nutrients, analyzed using a nutrition phase approach to evaluating nutrition support, enabled a more infant‐driven rather than age‐driven application of nutrition recommendations. This approach unmasked nutrient deficits occurring during the transition phase. Overcoming nutrient deficits in this nutrition phase should be prioritized to improve the nutrition management of preterm infants.  相似文献   
102.
103.
OBJECTIVES: This study investigated the independent and relative effects of family structure, race, and poverty on the health of US children and youth under 20 years of age at two time periods, 1978 through 1980 and 1989 through 1991. METHODS: Data were from the National Health Interview Surveys. Multivariate logit regression methods were used to analyze the effects of family structure, poverty, and race on children's health. RESULTS: Children in families headed by single mothers, Black children, and those living below 150% of the poverty index were much more likely to be in poor or fair health than children in two-parent families, White children, or those in more affluent families. Poverty had the strongest effect on child health in both time periods. CONCLUSIONS: The association between children's health and living below 150% of the poverty index is not explained by race or family structure. The disparity in child health by family income has serious consequences for both the child and society.  相似文献   
104.
The EuroQoL EQ-5D and MOS SF-36 are two generic quality of life measures that differ significantly in their design (the former being an index and the latter a profile). Both have been extensively used in evaluating interventions in acute disease. This study tested their comparative performance in a survey of patients with relapsing-remitting multiple sclerosis (MS).
METHODS: 309 patients with diagnosed relapsing-remitting MS were identified through the records of 5 specialist centers in North West England. Patients were contacted by telephone by a specialist MS nurse and asked to complete a set of questionnaires distributed by mail. The questionnaire booklet reproduced the English version of SF-36, together with the EQ-5D and a self completion form of the Barthel. Minimal additional background information was obtained from all respondents; 4 weeks following their completion of the initial booklet, a second identical booklet was sent to the first 200 initial respondents. Patients in this re-test sub-group were asked whether their health status had improved, deteriorated, or remained unchanged over the intervening period.
RESULTS: Of the 200 patients in the test/re-test subgroup, 144 (72%) replied on both occasions. Paired t-tests for the PCS, MCS, and general health perception scores on the SF-36 failed to generate comprehensive evidence of reliability. The weighted index form of the EQ-5D and the visual analogue scale self-ratings provided superior evidence of reliability. Standardized response means for both measures confirmed this general pattern.
CONCLUSION: EQ-5D performs satisfactorily as a generic measure of health-related quality of life in patients with MS.  相似文献   
105.
Purpose: To develop and preliminarily evaluate a Social Difficulties Inventory (SDI) for use in oncology practice. Methods: Item generation from patients (n=96), staff (n=49) and the literature. Questions constructed and pre-tested (n=42) resulting in a 22-item questionnaire. Psychometric evaluation (n=271) assessed frequency of endorsement, factor structure, summated scales and construct validity followed by randomisation to criterion validity or test-retest arms. Results: Items met preset frequency of endorsement criteria. Factor analysis revealed a four-factor structure, three clearly definable, (1) Physical ability, (2) Providing for the family and (3) Contact with others, explaining 45.8% variance. Summated scales developed from these demonstrated good reliability (Cronbachs alpha > 0.7) and were used to test and confirmed construct validity. Several comparators from the Life Events and Difficulties Schedule (LEDS) and CAncer Rehabilitation Evaluation System Short Form (CARES-SF) tested criterion validity and majority agreements were moderate to good. Test–retest reliability was good with most kappa values > 0.6. One item was eliminated resulting in a 21-item questionnaire. Conclusion: The SDI is relevant and easy to understand. Initial psychometric evaluation was encouraging. Ongoing work to evaluate the clinical meaning and utility of the instrument and to examine the relationships between SDI scores and clinical outcomes will provide guidance about its usefulness as an assessment tool in routine oncology practice.Presented in part at the British Cancer Research Meeting (poster presentation) 2001 and at the World Congress of Psycho-Oncology (poster presentation) 2003.  相似文献   
106.
The aim of this study was to identify the level of isoflavone intake (total isoflavones, daidzein and genistein) in four European countries: Ireland, Italy, The Netherlands and the UK. For this purpose national food composition databases of isoflavone content were created in a comparable way, using the Vegetal Estrogens in Nutrition and the Skeleton (VENUS) analytical database as a common basis, and appropriate food consumption data were selected. The isoflavone intake in Ireland, Italy, The Netherlands and the UK is on average less than 1 mg/d. Small groups of consumers of soya foods could be identified in Ireland, The Netherlands and the UK. The estimated intake levels are low compared with those found in typical Asian diets (approximately 20-100 mg/d) and also low compared with levels where physiological effects are expected (60-100 mg/d). The results (including a subgroup analysis of soya product consumers) showed that such levels are difficult to achieve with the European diets studied here.  相似文献   
107.
The present study used a systematic review approach to identify relevant randomised control trials (RCT) with vitamin D and then apply meta-regression to explore the most appropriate model of the vitamin D intake-serum 25-hydroxyvitamin D (25(OH)D) relationship to underpin setting reference intake values. Methods included an updated structured search on Ovid MEDLINE; rigorous inclusion/exclusion criteria; data extraction; and meta-regression (using different model constructs). In particular, priority was given to data from winter-based RCT performed at latitudes >49·5°N (n 12). A combined weighted linear model meta-regression analyses of natural log (Ln) total vitamin D intake (i.e. diet and supplemental vitamin D) v. achieved serum 25(OH)D in winter (that used by the North American Dietary Reference Intake Committee) produced a curvilinear relationship (mean (95 % lower CI) serum 25(OH)D (nmol/l) = 9·2 (8·5) Ln (total vitamin D)). Use of non-transformed total vitamin D intake data (maximum 1400 IU/d; 35 μg/d) provided for a more linear relationship (mean serum 25(OH)D (nmol/l) = 0·044 × (total vitamin D)+33·035). Although inputting an intake of 600 IU/d (i.e. the RDA) into the 95 % lower CI curvilinear and linear models predicted a serum 25(OH)D of 54·4 and 55·2 nmol/l, respectively, the total vitamin D intake that would achieve 50 (and 40) nmol/l serum 25(OH)D was 359 (111) and 480 (260) IU/d, respectively. Inclusion of 95 % range in the model to account for inter-individual variability increased the predicted intake of vitamin D needed to maintain serum 25(OH)D ≥ 50 nmol/l to 930 IU/d. The model used to describe the vitamin D intake-status relationship needs to be considered carefully when setting new reference intake values in the Europe.  相似文献   
108.
This study investigates the relationship between adverse pregnancy outcomes in high-risk African American women in Washington, DC and sociodemographic risk factors, behavioral risk factors, and the most common and interrelated medical conditions occurring during pregnancy: diabetes, hypertension, preeclampsia, and Body Mass Index (BMI). Data are from a randomized controlled trial conducted in 6 prenatal clinics. Women in their 1st or 2nd trimester were screened for behavioral risks (smoking, environmental tobacco smoke exposure, depression, and intimate partner violence) and demographic eligibility. 1,044 were eligible, interviewed and followed through their pregnancies. Classification and Regression Trees (CART) methodology was used to: (1) explore the relationship between medical and behavioral risks (reported at enrollment), sociodemographic factors and pregnancy outcomes; (2) identify the relative importance of various predictors of adverse pregnancy outcomes; and (3) characterize women at the highest risk of poor pregnancy outcomes. The strongest predictors of poor outcomes were prepregnancy BMI, preconceptional diabetes, employment status, intimate partner violence, and depression. In CART analysis, preeclampsia was the first splitter for low birthweight; preconceptional diabetes was the first splitter for preterm birth (PTB) and neonatal intensive care admission; BMI was the first splitter for very PTB, large for gestational age, Cesarean section and perinatal death; employment was the first splitter for miscarriage. Preconceptional factors strongly influence pregnancy outcomes. For many of these women, the high risks they brought into pregnancy were more likely to impact their pregnancy outcomes than events during pregnancy.  相似文献   
109.
The concentrations of tocopherols and carotenoids are lowered in umbilical cord blood plasma, which may have a negative effect on antioxidant protection in neonates. Smoking may adversely affect dietary intakes and plasma concentrations of carotenoids. The dietary intakes of vitamin E and beta-carotene were assessed in 66 pregnant women (31 smokers and 35 non-smokers) between 10 and 20 weeks gestation using a food frequency questionnaire. The concentrations of alpha-tocopherol and beta-carotene were measured in maternal plasma at the time of the dietary assessment, and in the matched umbilical cords of their newborn after delivery. In smoking and non-smoking mothers, the mean intakes of vitamin E (9.3 [SD 5] and 8.2 [SD 5] mgd-1) and beta-carotene (3464 [SD 1885] and 2977 [SD 1503] micrograms d-1) were not significantly different. The plasma concentrations of alpha-tocopherol (20.8 [SD 4] and 20.5 [SD 4] mumol L-1), the alpha-tocopherol to lipid ratios (3.2 [SD 0.8] and 3.5 [SD 0.8]) and the plasma concentrations of beta-carotene (0.22 [SD 0.1] and 0.22 [SD 0.1] mumol L-1) were not significantly different in smoking and non-smoking mothers. There were no significant differences in plasma alpha-tocopherol (7.4 [SD 2] and 7.3 [SD 2] mumol L-1), in alpha-tocopherol to lipid ratios (3.2 [SD 0.6] and 2.8 [SD 0.6]) or in beta-carotene concentrations (0.05 [SD 0.04] and 0.03 [SD 0.02] mumol L-1) in cords from newborns of smoking and non-smoking mothers. There was a significant correlation (r = 0.41, P = 0.015) between dietary intakes and plasma concentrations of beta-carotene in non-smoking mothers. However, this relationship was not significant in smoking mothers (r = 0.28, P = 0.12). There were no relationships between dietary intakes and plasma concentrations of tocopherol. These results indicate that smoking during pregnancy does not appear to affect the dietary intakes or plasma concentrations of alpha-tocopherol and beta-carotene in pregnant women or their babies. However, smoking does influence the relationship between dietary intakes and plasma levels of beta-carotene.  相似文献   
110.
Some conceptual problems in multivariable analyses of perinatal mortality   总被引:3,自引:0,他引:3  
Biostatisticians, epidemiologists and other researchers in maternal and child health have often used multivariable analysis to investigate associations with perinatal and infant mortality. A review of reports of such multivariable analyses published over the last 35 years revealed four problems that occur repeatedly. (1) Variables that are intermediate in the causal pathway between some study variables and perinatal death ('intervening variables') are controlled as though they were confounders. (2) When birthweight is analysed as an intervening variable, it is entered into the analysis in a few large categories, such as above and below 2500 g. This is not an adequate way of controlling for birthweight. (3) Social and demographic variables often interact statistically with birthweight in their effects on perinatal mortality, but these interactions have not been analysed in most multivariable studies. (4) Highly intercorrelated variables that represent similar theoretical constructs are entered simultaneously into one regression analysis. Solutions to these problems are suggested. Analytical approaches in which investigators use knowledge of biological and medical subject matter to make judgements about confounding and causal inference are encouraged.  相似文献   
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