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991.
PurposeWe retrospectively reviewed long-term outcomes of patients with inverted papilloma (IP) treated with radiation therapy at our institution.Methods and MaterialsFrom 1969 to 2008, 13 patients with advanced or recurrent IP (n = 12) or cylindrical papilloma (n = 1) were treated with radiation therapy. The median age at radiation therapy was 53 years old (range, 32-84). Nine patients received postoperative radiation therapy, 3 received definitive radiation therapy, and 1 received preoperative radiation therapy. Of the 10 patients treated with combined-modality treatment, 1 underwent craniofacial resection and 9 underwent open resection. Eight patients, 4 patients, and 1 patient received once-daily fractionation, twice-daily fractionation, and planned split-course radiation therapy, respectively, to a median dose of 65 Gy (range, 45.3-70.4 Gy).ResultsThe median follow-up was 16.2 years. Actuarial 15-year overall and cause-specific survival rates were 62% and 82%. Fifteen-year actuarial local and regional control rates were 45% and 73%. Fifteen-year local-regional control rates for IP alone and IP associated with squamous cell carcinoma (IP-SCC) at the time of treatment were 80% and 16%. Fifteen-year overall survival rates for IP alone and IP-SCC were 40% and 50%. The only severe treatment complication was a grade 3 central nervous system radionecrosis. The most common grade 1-2 toxicities were mucositis (61%), pain (46%), conjunctivitis (31%), xerostomia (31%), epiphora (31%), and anorexia (31%).ConclusionsWhile surgery is the primary treatment for IP, radiation therapy should be considered in patients with SCC, multiply recurrent IPs, and incompletely resectable IP. Radiation therapy is associated with a relatively low risk of severe complications. Despite more aggressive treatment, local failure remains a considerable challenge.  相似文献   
992.
This study examined the link between cognitive biases (i.e., attention biases and implicit associations) and symptoms of depression and eating disorders and whether the content of these biases is disorder-specific. These hypotheses were examined with a sample of 202 undergraduate women. Cognitive biases were measured via computer-based tasks (i.e., the probe detection task and the Implicit Association Test) and symptom levels were measured via interview and self-report. Partially supporting the main hypothesis, symptoms of depression and eating disorders were significantly correlated with disorder-specific implicit associations but not attentional biases. Partially supporting the specificity hypothesis, there was evidence for stronger associations between symptoms of eating disorders and eating specific implicit associations.  相似文献   
993.
994.
Background: Youth involved in the juvenile justice system experience a disproportionate prevalence of serious mental health issues, substance abuse, and are at an increased risk of engaging in risky sexual practices. Gender differences exist, with girls at a markedly greater risk of acquiring a sexually transmitted disease. Objectives: The present study seeks to determine if there are subgroups of male and female youth who differ in their health risk behavior. If so, do any male or female subgroups at different levels of health risk differ in regard to their sociodemographic and psychological factors, and finally, what are intervention/service delivery implications of these differences. Methods: Youth were participants in an innovative health service at a centralized intake facility located in a large southeastern U.S. city. Latent class analysis and multinomial logistic regression is utilized to examine the heterogeneity of health risk behaviors across gender groups in a sample of 777 newly arrested youth. Results: Results indicate a three class solution provided the optimal fit with the data for each gender group: a Lower Health Risk group, a Higher Health Risk group, and a Highest Health Risk group. Multinomial logistic regression analysis identified significant sociodemographic and depression effects among both male and female youth. Conclusions/Importance: Youth characterized by risky sexually behavior, elevated depression, and drug involvement should be the focus of integrated intervention services. This study documents the critical need for front end, juvenile justice intake facilities to provide behavioral and public health screening, with treatment follow-up, on newly arrested youth.  相似文献   
995.
996.
Although studies of the skin have provided fundamental models for innate and adaptive immune surveillance of body surfaces, there remains relatively little understanding of the role that epithelial cells play in sensing infection and/or organ dysfunction, and the pathways available to them to communicate with local and systemic immune cells. In particular, evidence is emerging for a novel stress response initiated by local lymphocytes, rather than dendritic cells, and based on their recognition of epithelial stress-induced antigens. Its consequences are to sustain tissue integrity by providing immunoprotection and novel modes of immunoregulation, whereas its dysregulation may promote body surface immunopathologies.  相似文献   
997.
A leading hypothesis explaining Phanerozoic mass extinctions and associated carbon isotopic anomalies is the emission of greenhouse, other gases, and aerosols caused by eruptions of continental flood basalt provinces. However, the necessary serial relationship between these eruptions, isotopic excursions, and extinctions has never been tested in geological sections preserving all three records. The end-Triassic extinction (ETE) at 201.4 Ma is among the largest of these extinctions and is tied to a large negative carbon isotope excursion, reflecting perturbations of the carbon cycle including a transient increase in CO2. The cause of the ETE has been inferred to be the eruption of the giant Central Atlantic magmatic province (CAMP). Here, we show that carbon isotopes of leaf wax derived lipids (n-alkanes), wood, and total organic carbon from two orbitally paced lacustrine sections interbedded with the CAMP in eastern North America show similar excursions to those seen in the mostly marine St. Audrie’s Bay section in England. Based on these results, the ETE began synchronously in marine and terrestrial environments slightly before the oldest basalts in eastern North America but simultaneous with the eruption of the oldest flows in Morocco, a CO2 super greenhouse, and marine biocalcification crisis. Because the temporal relationship between CAMP eruptions, mass extinction, and the carbon isotopic excursions are shown in the same place, this is the strongest case for a volcanic cause of a mass extinction to date.  相似文献   
998.
999.
In response to inflammatory stimuli, dendritic cells (DCs) trigger the process of maturation, a terminal differentiation program required to initiate T-lymphocyte responses. A hallmark of maturation is down-regulation of endocytosis, which is widely assumed to restrict the ability of mature DCs to capture and present antigens encountered after the initial stimulus. We found that mature DCs continue to accumulate antigens, especially by receptor-mediated endocytosis and phagocytosis. Internalized antigens are transported normally to late endosomes and lysosomes, loaded onto MHC class II molecules (MHCII), and then presented efficiently to T cells. This occurs despite the fact that maturation results in the general depletion of MHCII from late endocytic compartments, with MHCII enrichment being typically thought to be a required feature of antigen processing and peptide loading compartments. Internalized antigens can also be cross-presented on MHC class I molecules, without any reduction in efficiency relative to immature DCs. Thus, although mature DCs markedly down-regulate their capacity for macropinocytosis, they continue to capture, process, and present antigens internalized via endocytic receptors, suggesting that they may continuously initiate responses to newly encountered antigens during the course of an infection.  相似文献   
1000.
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