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991.
This article puts forward the case that survey questionnaires, which are a type of measuring instrument, can and should be tested to ensure they meet their purpose. Traditionally survey researchers have been pre-occupied with standardising data collection instruments and procedures such as question wording and have assumed that experience in questionnaire design, coupled with pilot testing of questionnaires, will then ensure valid and reliable results. However, implicit in the notion of standardisation are the assumptions that respondents are able to understand the questions being asked, that questions are understood in the same way by all respondents, and that respondents are willing and able to answer such questions. The development of cognitive question testing methods has provided social researchers with a number of theories and tools to test these assumptions, and to develop better survey instruments and questionnaires. This paper describes some of these theories and tools, and argues that cognitive testing should be a standard part of the development process of any survey instrument.  相似文献   
992.
Low Birth Weight Across Generations   总被引:1,自引:0,他引:1  
Objectives: This study sought to determine the relationship between maternal birth weight, prenatal care usage, and infant birth weight. Methods: Stratified and logistic regression analyses were performed on a dataset of computerized Illinois vital records of White (N = 187,074) and African-American (N = 58,856) infants born between 1989 and 1991 and their mothers born between 1956 and 1975. Results: Among White mothers who received adequate prenatal care, the low birth weight (<2500 g) rate was 4% for infants of former low birth weight mothers (N = 5230) compared to 2.1% for infants of former nonlow birth weight mothers (N = 93,011), relative risk equaled 1.9(1.7–2.2); the population attributable risk of maternal low birth weight was 4.1%. Among African American mothers who received adequate prenatal care, the low birth weight rate was 15% for infants of former low birth weight mothers (N = 2196) compared to 7.2% for infants of former nonlow birth weight mothers (N = 14,607), relative risk equaled 2.1(1.9–2.4); the population attributable risk of maternal low birth weight was 10.9%. The maternal–infant birth weight associations were consistent across all maternal age, education, marital status, and prenatal care categories. Conclusions: Maternal low birth weight is a risk factor for infant low birth weight independent of risk status during the current pregnancy. A greater percentage of low birth weight African American (compared to White) infants are attributable to maternal low birth weight.  相似文献   
993.
To explore ways to integrate a youth development approach into child welfare work, a Delphi survey of experts was conducted. In particular, the Delphi survey technique was used to generate suggestions regarding: 1) the training needs of child welfare workers dealing with youth transitioning out of care, and 2) potential policy approaches to change in the child welfare system for these youth. A first round survey elicited suggestions of panel respondents and a second round survey requested the rating of these suggestions. Findings illustrate the importance of a holistic approach in working with these youth, as well as the importance of connection and relationship. Training approaches also were perceived as a feasible policy response to helping youth transition from care to independent living.  相似文献   
994.

Background  

HealthWise South Africa: Life Skills for Adolescents (HW) is an evidence-based substance use and sexual risk prevention program that emphasizes the positive use of leisure time. Since 2000, this program has evolved from pilot testing through an efficacy trial involving over 7,000 youth in the Cape Town area. Beginning in 2011, through 2015, we are undertaking a new study that expands HW to all schools in the Metro South Education District.  相似文献   
995.
Recovery from substance use is a vital concern for many women with human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS). This qualitative study explores the meaning of women's HIV infection for their transition from drug use to recovery. Interviews were conducted with 15 female clients of a drug treatment program and AIDS nursing home in New York City. For most participants, HIV did not constitute the main reason for starting their recovery. The dual diagnosis program, however, facilitates an important transformation of the meaning of HIV/AIDS. Previously viewed as just another reason to use drugs, women now increasingly perceive their HIV infection as an incentive to stay clean and sober.  相似文献   
996.
A set of recombinant, live attenuated human parainfluenza virus type 1 (rHPIV1) vaccine candidates was evaluated for attenuation, immunogenicity, and protective efficacy in African green monkeys (AGMs). Temperature sensitive (ts) and non-ts attenuating (att) mutations in the P/C and L genes were introduced individually or in various combinations into rHPIV1, including the C(R84G) and HN(T553A) mutations identified in the present work and the C(F170S), L(Y942A), and L(L992C) mutations identified previously. The rHPIV1 vaccine candidates exhibited a spectrum of attenuation in AGMs. One genetically and phenotypically stable vaccine candidate, rC(R84G/F170S)L(Y942A/L992C), was attenuated and efficacious in AGMs and is a promising live attenuated intranasal HPIV1 vaccine candidate suitable for clinical evaluation.  相似文献   
997.
Health sector reform and the interpretation of policy context.   总被引:4,自引:0,他引:4  
Health sector reform is on the policy agenda of national governments and international agencies. This paper focuses on the policy process of health sector reform and, more specifically, the policy context. The importance of understanding policy context is emphasised and the elements of policy context are discussed. These are: demographic and epidemiological change; processes of social and economic change; economic and financial policy; politics and the political regime; ideology, public policy and the public sector. The paper then discusses the means for, and methods of, interpretation of the policy context. Particular emphasis is placed on linking policy context with an overall understanding of the policy process, the 'messiness' of policy-making, the interrelationship between the contextual factors, the contextual factors interpreted by policy actors, the use of analytical categories in the policy analysis. The paper concludes on the importance of strengthening policy analysis for effective health sector reform.  相似文献   
998.
Acute hepatitis B infection in England and Wales: 1985-96   总被引:3,自引:0,他引:3  
Confirmed acute hepatitis B infections are reported to the Public Health Laboratory Service Communicable Disease Surveillance Centre by laboratories in England and Wales. These reports have been used to monitor trends in the incidence of hepatitis B virus (HBV) infection over time, and between exposure categories and age groups. Between 1985 and 1996 a total of 9252 cases of acute HBV infection were reported; the number of reports fell from 1761 in 1985 to 581 in 1996. Most infections were reported in adults aged 15-44 years [n = 7365 (80%)], and infections were more commonly reported in males [n = 6490 (70%)] than females [n = 2658 (29%)]. The probable means of acquisition was known for just over half of all adult cases [4827/8956 (54%)]. Injecting drug use was the most common exposure [n = 1901 (21%)], followed by sex between men and women [n = 1140 (13%)] and sex between men [n = 1025 (11%)]. The number of infections in injecting drug users fell in the late 1980s, but increased again from 1991 onwards. In children aged under 15 years, infections acquired by mother to baby transmission accounted for 35/170 (21%) of the total. Surveillance indicates that the incidence of acute hepatitis B infection fell in the late 1980s, probably reflecting changed behaviour in injecting drug users. An increase in the number of infections in injecting drug users since 1993 may indicate ongoing transmission that has not been contained by the introduction of needle exchange schemes or by selective vaccination.  相似文献   
999.
BACKGROUND: Early detection of prostate cancer is thought to be effective, and indirect evidence suggests that men aged 50 to 69 years will benefit most while those aged 70 and older will benefit least from it. The goal of our study was to describe usual care patterns for prostate-specific antigen (PSA) testing by primary care physicians in the United States. METHODS: We analyzed office visits made by adult men to family physicians, general internists, general practitioners, and geriatricians recorded by the 1995 and 1996 National Ambulatory Medical Care Surveys. Our outcome measure was the probability of a primary care physician ordering a PSA test during a visit. RESULTS: Seventeen percent of the tests reported were among men aged younger than 50 years, 50% were for men aged 50 to 69 years, and 33% were for men aged 70 years and older. The frequency of PSA testing was highest during visits by men aged 60 to 64 years (7.1%), 65 to 69 years (7.0%), 70 to 74 years (7.0%), and 75 to 79 years (6.3%) but lower for men aged older than 80 years (3.1%). CONCLUSIONS: Our findings suggest that during the mid-1990s prostate cancer screening decisions by primary care physicians were not sensitive to patients' ages.  相似文献   
1000.
Summary Background. It is widely believed that antioxidant micronutrients obtained from fruit and vegetables afford significant protection against cancer and heart disease, as well as ageing. Flavonoids are potential antioxidants found in food such as onions; information on their effectiveness in vivo is so far lacking. Aims. To determine uptake as well as in vivo antioxidant effects of flavonoids from foods. Methods. Six healthy non-obese normocholesterolaemic female volunteers in the age range 20–44 years participated in a randomised two-phase crossover supplementation trial to compare the antioxidant effects associated with (a) a meal of fried onions and (b) a meal of fried onions and fresh cherry tomatoes. Plasma flavonoids, lymphocyte DNA damage, plasma ascorbic acid, tocopherols and carotenoids, urinary malondialdehyde and 8-hydroxy-2’-deoxyguanosine were determined to assess flavonoid absorption and antioxidant efficacy. Results. Flavonoid glucosides (quercetin-3-glucoside and isorhamnetin-4-glucoside) were significantly elevated in plasma following ingestion of the onion meal and the increases were associated with an increased resistance of lymphocyte DNA to DNA strand breakage. A significant decrease in the level of urinary 8-hydroxy-2’-deoxyguanosine was evident at 4 h following ingestion of the onion meal. After the combined tomato and onion meal, only quercetin was detected in plasma. Endogenous base oxidation was decreased but resistance to strand breakage was unchanged. There was no significant change in the excretion of urinary malondialdehyde following either meal. Conclusion. Both meals – onions, and onions together with tomatoes – led to transient decreases in biomarkers of oxidative stress, although the particular biomarkers affected differ. It is possible that the differences in patterns of response reflect the different uptakes of flavonoids but the underlying mechanism is not understood. Received: 1 April 2000, Accepted: 1 August 2000  相似文献   
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