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81.
This article reviews the basic principles of patient evaluation and surgical techniques to accomplish extraction of teeth in an uncomplicated manner. Also presented are techniques for extraction-site grafting with bioactive glass.  相似文献   
82.
Interventions are needed to improve the quality of care for schizophrenia. However, in designing these interventions it would be helpful to understand better which patients are at highest risk for poor-quality care and why care for this disorder is often of poor quality. We study the extent to which patient and treatment factors are associated with poor-quality care in 224 patients randomly sampled from two mental health clinics. Quality of medication management is evaluated using an established method based on national treatment recommendations. Multivariate regression is used to study the effect of patient and treatment factors on treatment quality, controlling for provider. Risk for poor-quality care was greater for patients who were more severely ill, older, and less compliant with treatment recommendations. There were trends toward poor management of symptoms in men and substance abusers, and poor management of side effects in Black patients. Provision of poor-quality care was associated with failure to document symptoms and side effects in the medical record. Interventions to improve care for schizophrenia should attend to the need for accurate clinical assessment and strategies for managing challenging clinical situations.  相似文献   
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The purpose of this study was to assess the effects of a six-week summer break and of dance preparations at the beginning of the new season following the break, on selected physiological parameters. Seventeen professional ballerinas (mean age 27.2 +/- 1.4 years, mean height 160.2 +/- 6.2 cm) volunteered. They were assessed just before and immediately after their normal summer break, during which very little or no physical work was reported. Eight of these dancers were assessed for a third time, 2-3 months after the end of the break, while they were into preparing for the new season. More specifically, compared to pre-break data, the six-weeks of holiday was followed by a 15% overall increase in the three flexibility tests (from 334 to 386 degrees, P < 0.01), a 14% increase in peak anaerobic power (from 350 to 400 watts; P < 0.01), a 16% increase in leg strength (from 143 to 166 Nm; P < 0.01) (i.e. the mean performance of left and right knee extension added to the mean performance of left and right knee flexion), and a 10% increase in VO2max (from 41.2 to 45.2 ml/kg/min; P < 0.05). The third set of data, 2-3 months after the end of the break, revealed further significant increases by 24% in leg-strength (P < 0.005) and 17% in VO2max (P < 0.01) compared to pre-holiday data. Despite the lack of a control group, the present results fit with the hypothesis of a degree of "burnout" at the end of the season, which negatively affected the mechanisms of fitness and conditioning. A six-week summer-break can act as a restorer of these mechanisms. Two to three months into the new season, positive adaptations to exercise appeared to confirm recovery from the "burnout" or overtraining phenomenon. More research is required on the effects of demanding dance schedules on fitness and conditioning, and how such schedules might adversely affect dance performance and dancers' careers.  相似文献   
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RATIONALE AND OBJECTIVES: Auditing has received much attention recently as a method for radiologists to use to evaluate their interpretation of screening mammograms. U.S. Food and Drug Administration regulations require that some sort of audit be in place before a mammography screening facility can receive accreditation. Auditing presents a unique opportunity to monitor accuracy continually and identify problems early. Audit data present unique challenges, however, and appropriate methods must be used to control the risk of errors. MATERIALS AND METHODS: This article introduces a simple method for the task of deciding if a radiologist yields an acceptable positive predictive value based on audit. The method is based on "sequential" decision-making techniques that have found wide application in quality control problems. These techniques are developed for diagnostic radiology and embodied in an easy-to-use decision-making chart. RESULTS: Several examples, based on audit data from actual mammography facilities, provide insights into the use of these charts and the influence of (a) the selection of standards, (b) the selection of error risks, and (c) radiologist variability. The examples also serve to demonstrate another important property of this method--that is, it specifies the minimum amount of data that has to be collected before any decision can reliably be made. CONCLUSION: The chart presented in this article provides a method by which audit data can be used objectively to evaluate the accuracy of screening mammogram interpretation. The method controls the risk of either falsely accepting an unqualified radiologist or falsely rejecting a qualified radiologist. It should be a useful tool to radiologists who must evaluate their own practices.  相似文献   
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Measurement of treatment costs is important in the evaluation of medical interventions. Accurate cost estimation is problematic, when cost records are incomplete. Methods from the survival analysis literature have been proposed for estimating costs using available data. In this article, we clarify assumptions necessary for validity of these techniques. We demonstrate how assumptions needed for valid survival analysis may be violated when these methods are applied to cost estimation. Our observations are confirmed through simulations and empirical data analysis. We conclude that survival analysis approaches are not generally appropriate for the analysis of medical costs and review several valid alternatives.  相似文献   
89.
Beliefs about the extent to which health problems can be prevented reflect an understanding that preventive measures can reduce adverse health events and the level of control individuals perceive that they hold over the factors that affect their health. A population survey of 1659 people conducted in 1995 in south western Sydney, Australia, found that only child drownings, tooth decay, skin cancer, and burns and scalds were considered all or mostly preventable by more than 50% of the sample. The majority of respondents did not believe that heart attacks, cervical cancer, high blood pressure, serious road injury, lung cancer and asthma deaths were all or mostly preventable. Logistic regression analysis showed that people born in an English speaking country, those with more than 10 years of education and men were significantly more likely to recognize a number of key conditions as highly preventable. The findings suggest that, in spite of the range of prevention efforts in Australia to date, these are not matched by strong beliefs within the community that prevention is possible. Communication of the opportunities and methods for prevention needs to be improved, particularly among certain population groups. The findings also indicate a need to examine social and environmental factors which are potentially reducing confidence, and subsequently and adoption of preventive behaviours.  相似文献   
90.
Sj?gren's syndrome is a complex autoimmune disorder, that occurs almost exclusively in females, induces extensive lymphocyte accumulation in lacrimal and salivary glands, and represents one of the leading causes of dry eye and mouth in the world. The purpose of this study was to determine whether the profound, gender-related differences observed in the magnitude of exocrine gland inflammation in Sj?gren's syndrome may also be found in tissues of mouse models of this disorder. Lacrimal and submandibular glands were obtained from adult MRL/lpr, MRL+/+ (MRL+), NZB/NZW F1 (F1), C3H/lpr, C3H/gld (gld), C57BL/6-lpr/lpr [B6/lpr; with (bcl-2(+)/lpr) or without (bcl-2(-)/lpr) bcl-2 transgene insertion] and nonobese diabetic (NOD) mice after the onset of autoimmune disease, and processed for microscopy and image analysis. Our results showed that: (1) the extent of inflammation was significantly greater in lacrimal glands of female MRL/lpr, MRL+, F1, C3H/lpr and gld mice, and salivary glands of female MRL+, F1 and gld mice, relative to those of males; (2) the severity of inflammation in NOD mice showed a tissue-specific pattern: inflammation was far worse in lacrimal glands of males, whereas immune pathology was far greater in salivary tissues in females; and (3) no gender-related variations were present in the degree of inflammation in lacrimal glands of bcl-2(+)/lpr and bcl-2(-)/lpr mice or in submandibular tissues of MRL/lpr, C3H/lpr, bcl-2(+)/lpr and bcl-2(-)/lpr mice. Our findings demonstrate that gender-, strain- and tissue-related differences exist in the extent of inflammation in several mouse models of Sj?gren's syndrome.  相似文献   
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