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Background: Development of the epidermal permeability barrier (EPB) is essential for neonatal life. Defects in this barrier are found in many skin diseases such as atopic dermatitis.Objective: We investigated the effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on the development and function of the EPB.Methods: Timed-pregnant C57BL/6J mice were gavaged with corn oil or TCDD (10 μg/kg body weight) on gestation day 12. Embryos were harvested on embryonic day (E) 15, E16, E17, and postnatal day (PND) 1.Results: A skin permeability assay showed that TCDD accelerated the development of the EPB, beginning at E15. This was accompanied by a significant decrease in transepidermal water loss (TEWL), enhanced stratification, and formation of the stratum corneum (SC). The levels of several ceramides were significantly increased at E15 and E16. PND1 histology revealed TCDD-induced acanthosis and epidermal hyperkeratosis. This was accompanied by disrupted epidermal tight junction (TJ) function, with increased dye leakage at the terminal claudin-1–staining TJs of the stratum granulosum. Because the animals did not have enhanced rates of TEWL, a commonly observed phenotype in animals with TJ defects, we performed tape-stripping. Removal of most of the SC resulted in a significant increase in TEWL in TCDD-exposed PND1 pups compared with their control group.Conclusions: These findings demonstrate that in utero exposure to TCDD accelerates the formation of an abnormal EPB with leaky TJs, warranting further study of environmental exposures, epithelial TJ integrity, and atopic disease.Citation: Muenyi CS, Leon Carrion S, Jones LA, Kennedy LH, Slominski AT, Sutter CH, Sutter TR. 2014. Effects of in utero exposure of C57BL/6J mice to 2,3,7,8-tetrachlorodibenzo-p-dioxin on epidermal permeability barrier development and function. Environ Health Perspect 122:1052–1058; http://dx.doi.org/10.1289/ehp.1308045  相似文献   
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Educational campaigns and legislative actions may have led to an overall decrease in the prevalence of volatile substance misuse (VSM) in many countries; however, it is still a common practice throughout the world. Studies currently suggest that girls are misusing volatile substances more than before and at a prevalence rate equal to or exceeding that of boys in several countries. Products that may be misused are ubiquitous and relatively easy to acquire. The most commonly misused substances in recent studies are fuels such as butane or petrol and compressed gas dusters and deodorants that may contain fluorocarbons and/or butane. Detection of VSM is challenging, therefore physicians must maintain a high level of suspicion based on history and clinical presentation. Clues to misuse are often subtle and may include the patient's proximity to a volatile substance or paraphernalia when found intoxicated, dermal burns, blisters, pigments, or rashes, and chemical odors. The primary targets of toxicity are the brain and the heart. The leading cause of death from VSM is from ventricular dysrhythmias. Treatment of toxicity begins with support of airway, breathing, and circulation. Exogenous catecholamines should be avoided if possible due to the theoretical “sensitized” and irritable myocardium. In the case of ventricular dysrhythmias, direct current defibrillation and/or beta-adrenergic receptor antagonism should be used. New evidence demonstrates the addictive potential of VSM yet effective therapy remains uncertain. Further research is needed in developing methods for preventing, detecting, and treating the harmful effects of VSM.  相似文献   
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The term opioid refers to a broad class of medications that are used most frequently for their analgesic effects. Along with this effect, they also produce euphoria, and it is for this reason that they have been used illicitly, as well as medicinally, for thousands of years. While the most well-known complications of opioid use and misuse include respiratory and central nervous system depression, there are many other toxicities that have been associated with these drugs. Many complications can occur with multiple different opioids, such as non-cardiogenic pulmonary edema, while many of the complications are unique to the opioid used as well as the route of administration. This review focuses on the pulmonary complications associated with opioid use and abuse, but opioids can affect nearly every organ system. Their effects on the pulmonary system can be direct, such as causing granulomatous change, but they can also work indirectly. For example, opioids cause respiratory depression by decreasing sensitivity of peripheral chemoreceptors to carbon dioxide and decreasing activity in the central respiratory centers. Opioids have also been reported to affect the immune system, and place users at increased risk for many different infectious complications. Patients can have a wide array of signs and symptoms, sometimes making it difficult to recognize opioids as a cause for a patient’s clinical picture. Due to the sedative effects of opioids, patients are also often not able to provide a reliable history. Knowledge of the possible toxicities of opioids can help prepare a physician to recognize the many complications associated with opioid use.  相似文献   
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BackgroundPeriodontal disease is a major cause of tooth loss. Few studies have evaluated the residual area of the periodontal ligament in extracted teeth and, to the best of our knowledge, none from Latin America have done so regarding indications for extraction. The aim of this study was to evaluate the residual periodontal ligament (RPL) with respect to indication for extraction in a sample of teeth from a Brazilian Public Health Service district.Materials and methodsAll teeth extracted within the Public Health Service district of Santa Maria, Brazil, over a 5-month period were requested for analysis. A total of 414 teeth eligible for measurement were stained and evaluated for RPL using a stereo microscope. Participating Public Health Service dentists completed a questionnaire detailing demographic variables and indication for each extracted tooth. The percentage of RPL was determined for each tooth. Comparisons of RPL between teeth extracted on periodontal versus other indications were made using the Mann-Whitney test.ResultsRPL averaged 34.8% for teeth extracted on periodontal indications versus 79.5% for other teeth (P ≤ 0.001). When considering teeth with an RPL ≥ 30% as possible to maintain, 189 (76%) of the teeth extracted on periodontal indications could have been maintained. When RPL cut-off limits of ≥ 40% or ≥ 50% are applied, 93 (37%) and 43 (17%) teeth, respectively, could have been maintained.ConclusionThis study suggests that strictly based on RPL, a large number of teeth extracted on periodontal indications conceivably could be maintained.Key words: Cross-sectional studies, Prognosis, Tooth extraction, Tooth loss  相似文献   
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ObjectiveThis study assessed levels of anxiety, depression, and stress among family caregivers of children and adolescents with mental disorders in Ghana and the implication on medication adherence.DesignA cross-sectional study.SettingThe study was conducted at the outpatient departments of the three main public psychiatric hospitals in Ghana.ParticipantsTwo hundred and ten non-paid family caregivers of children and adolescents with mental disorders were recruited for this study.Main Outcome MeasureThe study assessed symptoms of anxiety, depression and stress among the caregivers and estimated caregiver-reported medication adherence.ResultsAbout 56.2%, 66.2% and 78% of the caregivers experienced severe anxiety, severe depression and moderate to severe stress symptoms respectively. From the multiple logistic regression model, while anxiety was significantly affected by religion and education, depression was influenced by sex, age, marital status, proximity to facility, and employment status. Female caregivers had about four times higher odds of being depressed compared to male caregivers (aOR: 3.81, 95% CI: 1.66 – 8.75). The caregiver-reported medication adherence was 11.9%. Anxiety was significantly predictive of medication adherence.ConclusionMost family caregivers of children and adolescents with mental disorders experienced symptoms of anxiety, depression and stress with anxiety having implications for medication adherence. The study findings underscore the need to consider psychological characteristics of caregivers and the provision of mental health support for them, as part of the routine health care for children and adolescents with mental disorders.FundingNone indicated  相似文献   
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Monoclonal antibodies to Staphylococcus aureus capsular polysaccharide types 5 and 8 were prepared and used to serotype 821 clinical isolates of S. aureus from four countries. The capsular polysaccharide-binding sites on the bacterial membrane were examined by transmission and scanning electron microscopy.  相似文献   
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