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1.
Mechanical scratching, a common external stress affecting the skin, is induced by various causes, such as pruritus. Scratch injury to epidermal keratinocytes upregulates the production and release of chemokine (C-C motif) ligand 20 (CCL20) in vitro, which selectively chemoattracts interleukin (IL)-17A-producing immune cells that express chemokine (C-C motif) receptor 6 (CCR6). In IL-17A-dominant psoriasis, scratch-induced CCL20 upregulation and subsequent accumulation of IL-17A-producing immune cells and CCR6+ mature dendritic cells may trigger the development of psoriatic lesions, a process known as the Koebner phenomenon. In IL-4/IL-13-dominant atopic dermatitis, pruritus and subsequent scratching are the primary symptoms. Scratch-induced CCL20 production from keratinocytes may explain why IL-17A levels are also elevated in atopic dermatitis. In contrast, mechanical scratching is likely to negatively regulate IL-13 signaling by upregulating the expression of IL-13 receptor α2, which serves as a decoy receptor for IL-13 in keratinocytes. In this review, we summarize current reports on topics related to the pathogenic role of epidermal scratch injury in psoriasis and atopic dermatitis.  相似文献   
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Delta-like canonical Notch ligand 3 (DLL3) is a member of the Delta/Serrate/Lag2 (DSL) Notch receptor ligand family and plays a crucial role in Notch signaling, which influences various cellular processes including differentiation, proliferation, survival, and apoptosis. DLL3 is expressed throughout the presomitic mesoderm and is localized to the rostral somatic compartments; mutations in DLL3 induce skeletal abnormalities such as spondylocostal dysostosis. Recently, DLL3 has attracted interest as a novel molecular target due to its high expression in neuroendocrine carcinoma of the lung. Moreover, a DLL3-targeting Ab-drug conjugate, rovalpituzumab tesirine (ROVA-T), has been developed as a new treatment with proven antitumor activity. However, the development of ROVA-T was suspended because of shorter overall survival compared to topotecan, the second-line standard treatment. Thus, several studies on the mechanism and function of DLL3 in several malignancies are underway to find a new strategy for targeting DLL3. In this review, we discuss the roles of DLL3 in various malignancies and the future perspectives of DLL3-related research, especially as a therapeutic target.  相似文献   
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Rutaecarpine is a major alkaloid isolated from Evodia rutaecarpa. Here, we investigated the effects of rutaecarpine on osteoclast differentiation induced by macrophage colony stimulating factor (M‐CSF) and receptor activator of nuclear factor κ‐B ligand (RANKL) in bone marrow‐derived macrophages (BMMs). Treatment with rutaecarpine significantly inhibited osteoclastogenesis and prevented bone resorption of BMM‐derived osteoclasts. Mechanistically, rutaecarpine decreased the protein level of nuclear factor of activated T cells cytoplasmic‐1 (NFATc1) and the phosphorylation of other signalling pathways during the osteoclast differentiation. Thus, rutaecarpine may be useful as a therapeutic agent for the treatment of bone diseases.  相似文献   
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Kazuya Yoshida  DDS  PhD    Akira Takagi  CDT    Yoichi Tsuboi  DDS  PhD    & Kazuhisa Bessho  DDS  PhD 《Journal of prosthodontics》2008,17(3):219-222
Maintenance of healthy periimplant soft tissue is a significant problem for orbital prosthesis wearers. Two female patients with orbital defects after malignant tumor resection were treated using custom‐made retentive components of an individual magnet for an Epitec System orbital prosthesis. Freestanding hygienic retentive components for an individual magnet were fabricated. An abutment replica was trimmed and modified, and using pattern resin, a magnetic keeper was cast and soldered to the abutment. The patients could maintain good hygiene and healthy periimplant soft tissue. This type of freestanding retentive component may be advantageous for the hygiene maintenance of periimplant soft tissue.  相似文献   
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BACKGROUND: Genetic polymorphisms for cytokines and their receptors have been proposed as potential markers for periodontal disease. Tumor necrosis factor receptor 2 (TNFR2) is one of the cell surface receptors for TNF-alpha. Recent studies have suggested that TNFR2 gene polymorphism is involved in autoimmune and other diseases. OBJECTIVES: The aim of the present study is to evaluate whether TNFR2(+587T/G) gene polymorphism is associated with chronic periodontitis (CP). METHODS: One hundred and ninety-six unrelated subjects (age 40-65 years) with different levels of CP were identified according to established criteria, including measurements of probing pocket depth (PPD), clinical attachment level (CAL), and alveolar bone loss (BL). All subjects were of Japanese descent and non-smokers. Single nucleotide polymorphism at position +587(T/G) in the TNFR2 gene was detected by a polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP) method. RESULTS: The frequency and the positivity of the +587G allele were significantly higher in severe CP patients than in controls (p=0.0097; odds ratio=2.61, p=0.0075; odds ratio=3.06). In addition, mean values of PPD, CAL, and BL were significantly higher in the +587G allele positive than in the negative subjects (p=0.035, 0.022, and 0.018, respectively). CONCLUSIONS: These findings suggest that the TNFR2(+587G) polymorphic allele could be associated with severe CP in Japanese.  相似文献   
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We performed an orthodontic treatment combined with mandibular distraction osteogenesis in a 15-year-old patient who wanted a correction of a chin deficiency and a protruding upper lip. The patient had an Angle Class II division 1 malocclusion with mandibular retrusion, a low mandibular plane angle, and scissors bite. First, a quad-helix appliance was applied to the mandibular dentition to correct the scissors bite in the bilateral premolar region. Later, a preadjusted edgewise appliance was applied to the maxillary and mandibular teeth. After 3 days, a mandibular distraction osteogenesis was performed. During and after the distraction, the open bite between the upper and lower dental arches was corrected using up and down elastics. The total treatment time with the edgewise appliance was 14 months. A skeletal Class I apical base relationship, good facial profile, and optimum intercuspation of the teeth were achieved with the treatment. The jaw-movement pattern on the frontal view did not change during gum chewing. However, the maximum gap without pain increased. The electromyographic (EMG) activity of the masseter and anterior temporalis muscles, and maximum occlusal force increased. The present case report suggests that an orthodontic treatment combined with mandibular distraction osteogenesis in a patient with mandibular retrusion in the late growth period might be effective for improving stomatognathic function.  相似文献   
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Objectives: This study aimed to investigate dental undergraduate students’ tobacco usage and social nicotine dependence in Australia. A special interest was to identify the role of factors such as age, gender, year of dental education and cohabitants’ smoking status for social nicotine dependence. Materials and methods: A sample of 252, first‐to‐fifth year undergraduate students in an Australian dental school was used. Each completed a self‐administered questionnaire. Results: The smoking rate was 4.8%. Current smokers displayed higher social nicotine dependence than those that had never smoked (t = 3.1, df = 244, P = 0.002). Dental undergraduate students that showed higher social nicotine dependence (P = 0.001, OR = 1.3, 95% CI: 1.1–1.6), or that had smoking cohabitants (P = 0.016, OR = 4.8, 95% CI: 1.3–17.0), were more likely to smoke. Students’ social nicotine dependence increased with year of dental study (P = 0.043, β = 0.4, t = 2.0). Social nicotine dependence enhanced tobacco usage among Year‐1‐to‐4 students (P = 0.005, OR = 1.4, 95% CI: 1.1–1.7) but not Year‐5 undergraduates (P = 0.432). Conclusions: Social nicotine dependence has become a developing issue in dental education. Tobacco control should be highlighted in the dental curriculum. Future investigations into the effects of dental education on social nocotine dependence and tobacco usage are indicated.  相似文献   
10.
BACKGROUND: The aim of the present study was to compare the effectiveness of Nd:YAG and CO2 laser treatment to that of ultrasonic scaling used as monotherapies by examining clinical parameters, subgingival microflora, and interleukin-1 beta (IL-1beta) in gingival crevicular fluid (GCF). METHODS: Eighteen patients, each of whom had 2 or more sites with probing depth measuring > 5 mm, were included this clinical trial. The 41 sites were randomly assigned treatment with either Nd:YAG laser alone (n = 14, 100 mj, 20 pps, 2.0 W, 120 seconds), CO2 laser alone (n = 13, 2.0 W, 120 seconds), or ultrasonic scaling alone (n = 14, maximum power, 120 seconds). At baseline and at 1, 4, and 12 weeks, clinical measurements (plaque index, PI; gingival index, GI; probing depth, PD; clinical attachment level, CAL; and bleeding on probing, BOP) were performed and subgingival plaque and GCF sampled. A quantitative analysis of Porphyromonas gingivalis was carried out using real-time polymerase chain reaction (PCR) procedures. The amounts of IL-1beta were estimated by an enzyme-linked immunosorbent assay (ELISA). RESULTS: Decreased inflammation and PD were observed in all 3 groups after treatment. A microbiological analysis indicated significant decreases in P. gingivalis in the Nd:YAG and scaling groups at 1, 4, and 12 weeks compared to baseline (P < 0.05). The amount of GCF significantly decreased in the Nd:YAG and scaling groups at 12 weeks. The amount of IL-1beta increased in the CO2 group from baseline to 1 week (P < 0.05). The Nd:YAG group tended to show a decrease in IL-1beta from 1 to 12 weeks, although these data were not statistically significant. CONCLUSIONS: Our data suggest that Nd:YAG laser and ultrasonic scaling treatments showed significant improvements regarding the clinical parameters and subgingival microflora compared to the baseline, but no significant difference was observed between the 3 groups.  相似文献   
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