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31.
32.
A new framework design is presented for resin-bonded, acid-etched, fixed partial dentures. This innovative design divided the restoration into two parts, each with a separate path of insertion. The preparation of abutment teeth required minimal reduction and the pontic could not be displaced during function. Thirty-five patients with missing posterior teeth have been treated with this imaginative approach and after approximately 2 years, there have been no debonding failures.  相似文献   
33.
Tumor-infiltrating lymphocyte (TIL) in the primary site of oral SCC treated with S-PVP of PVP therapy was collected respectively and its yield,that is calculating the amount of TIL per tumor tissue.The cytotoxicity of TIL against the target,Tca8113 was detected.The results showed that the yield of TIL in S-PVP group was three times over that in PVP group.At the ratio of 5 to 1 (effector to target) the cytotoxicity was 38% in S-PVP group and 32% in PVP group.There was no significant difference in its cytotoxicity between two groups.The results revealed that immunochemotherapy of S-PVP regimen for treating oral SCC had neither direct damage to tumor cell from the agents nor antitumor immune reactivity with BRM stimulating an increasing in numbers of TIL.  相似文献   
34.
MRI在口腔颌面部肿块诊断中的应用   总被引:1,自引:0,他引:1  
作者对38例发生在口腔颌面部肿块患者采用MRI检诊。结合缅针穿吸缅胞学检查,并与CT扫描对比研究。结果提示:对口腔颌面部肿块。管状瘤或临床怀疑肿瘤有颅底、眶尖、翼腭窝、咽侧、颈部大血管神经累及者。MRI扫描成像清晰。软组织分辨率高。能早期发现骨质侵蚀。作者还对MRI在监测颌面部癌瘤切除术后局部是否复发进行初步观察。  相似文献   
35.
OBJECTIVE: To evaluate the effect of compounds of Galla chinensis on the remineralisation of initial enamel carious lesions in vitro. METHODS: Sixty bovine enamel blocks with early lesions were prepared and randomly divided into six treatment groups. The lesions were subjected to a pH-cycling regime for 12 days. Each daily cycle included 4x1min applications with one of six treatments; 1000ppm F aq. (as NaF, positive control); deionized water (negative control); or 4000ppm aqueous solutions of four G. chinensis extracts (GCEs); GCE, GCE-B, GCE-B1, or GCE-B2. Surface enamel microhardness was measured on the enamel blocks before and after demineralisation, and after pH-cycling, and percentage surface microhardness recovery (%SMHR) was calculated. The enamel specimens were then sectioned (thickness ca. 80microm) and examined by polarized light microscopy. RESULTS: All samples rehardened significantly compared to baseline. Fluoride had a significantly greater effect than all other treatments. In the GCEs groups, %SMHR was significantly greater than DDW for the GCE, GCE-B and GCE-B1 groups. There was no significant difference between the GCE-B2 group and DDW. Polarized light microscopy showed that the thickness of the surface layer increased obviously in all specimens including NaF group, GCE group, GCE-B group and GCE-B1 group. Negative birefringent band appeared in the lesions body and the depth of the lesions was obviously reduced. CONCLUSION: The present study has demonstrated the potential of three GCEs (GCE, GCE-B and GCE-B1) to effect net rehardening of artificial carious lesions under dynamic pH-cyclic conditions.  相似文献   
36.
AIM: To present a systematic review of the effects of formocresol and ferric sulphate when used as medicaments in pulpotomized primary molar teeth. METHODOLOGY: The study list was obtained by using MEDLINE, the Cochrane Library, EMBASE and SCI search. Only those papers which met the inclusion criteria were accepted. The quality of studies used for meta-analysis was assessed by a series of validity criteria according to Jadad's scale. A systematic review and meta-analysis were performed. RESULTS: Eleven clinical studies comprising four randomized-clinical trials (RCTs), four controlled clinical trials (CCTs) and three retrospective studies were included. The results of the meta-analysis of six prospective clinical trials suggested that the two popular pulpotomy medicaments were not significantly different in terms of clinical outcomes, radiographic findings, prevalence of apical and furcal destruction, internal root resorption or pulp canal obliteration. The relative risk (RR) value and 95% CI for those parameters were 0.72 (0.43-1.23), 0.87 (0.59-1.30), 0.67 (0.27-1.66), 1.77 (0.56-5.58) and 1.41 (0.63-3.15), respectively. The overall clinical and radiographic success rates based on the data of treatments with ferric sulphate from the 11 studies included ranged from 78% to 100% (mean 91.6 +/- 8.15%) and from 42% to 97% (mean 73.5 +/- 18.40%), respectively. CONCLUSIONS: In primary molar teeth with exposure of vital pulps by caries or trauma, pulpotomies performed with either formocresol or ferric sulphate have similar clinical and radiographic success. Ferric sulphate may be recommended as a suitable replacement for formocresol.  相似文献   
37.
38.
Relationship between vitamin D receptor gene polymorphism and periodontitis   总被引:8,自引:0,他引:8  
Recent studies have shown that vitamin D receptor (VDR) gene polymorphism had regulatory effects on bone mineral density (BMD) and bone turnover. The VDR gene has also been indicated as a candidate gene for the susceptibility of osteoporosis. However, it is unclear whether VDR genotypes could be associated with alveolar bone loss of patients with periodontitis, or whether vitamin D receptor gene could be a candidate gene for susceptibility to periodontitis. The purpose of this study was to answer these two questions. METHODS: Twenty-four cases of adult periodontitis (AP), 37 cases of early onset periodontitis (EOP) and 39 healthy controls were recruited for the study. Individual samples of venous blood and DNA were obtained from each subject. Genotypes of the TaqI VDR gene were determined by PCR and TaqI restriction endonuclease digestion. RESULTS: One out of 24 AP patients, nine out of 37 EOP patients and two out of 39 healthy controls were detected with Tt genotype, while the rest had the TT genotype. The detected frequency of Tt genotype was significantly higher in EOP patients (24.3%) than in AP patients (4.2%) and healthy controls (5.1%). The frequency of t allele was also significantly higher in EOP patients. There was no statistical difference in the distribution of TaqI VDR genotypes between AP patients and healthy controls. The study suggests that Tt genotype might be a risk indicator for the susceptibility to EOP. Carriage of the allele (t) of the TaqI VDR gene may increase the risk of developing EOP.  相似文献   
39.
In this review, we discuss substrates and implant surfaces provided with micrometer-sized groove and ridge patterns. Such "microgrooves" influence cell behavior: the cells align themselves, and migrate guided by the surface grooves. This phenomenon is known as "contact guid-ance". First, cell structure and cell attachment behavior are described. Then techniques for the production of microgrooves are addressed, and a summary is given of a number of previous in-vitro and in-vivo experiments on this subject. Based on the knowledge of cell movement, we suggest a theory involving the dynamics of fibrous cellular components in the filopodium. Finally, future directions for this type of research, and implications for medical and dental implantology, are addressed. Received: September 27, 2000 / Accepted: June 7, 2001  相似文献   
40.
The human major histocompatibility complex (MHC) on chromosome 6 encodes three classical class-I genes: human leukocyte antigens (HLA) A, B, and C. These polymorphic genes encode a 43- to 45-kDa cell surface glycoprotein that, in association with the 12-kDa beta2-microglobulin molecule, functions in the presentation of nine amino acid peptides to the T-cell receptor of CD8-bearing T lymphocytes and killer inhibitory receptors on natural killer cells. In addition to these ubiquitously expressed, polymorphic proteins, the human genome also encodes several nonclassical MHC class-I-like, or class Ib, genes that, in general, encode nonpolymorphic molecules involved in various specific immunological functions. Many of these genes, including CD1, the neonatal Fc receptor for IgG, HLA-G, HLA-E, the MHC class-I chain-related gene A, and Hfe, are prominently displayed on epithelial cells, suggesting an important role in epithelial cell biology.  相似文献   
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