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61.
This study describes dental caries data and fluorosis in seven municipalities in the Sorocaba region, S o Paulo State, Brazil, comparing those with fluoridated as opposed to non-fluoridated water. Criteria were those proposed by the World Health Organization (WHO, 1997), adapted by the School of Public Health, University of S o Paulo. The sample was selected at random, without replacement, and was calculated by age, accepting a design error of 2 and a sampling loss of 20% (n = 96 per age). There were six trained examiners, with accepted agreement percentage above 89% for all variables. In the Sorocaba region, the dmft index in 5 year-old children was 3.1, and 37.6% were caries-free (DMFT = 0). At age 12, 32.3% were caries-free (DMFT = 0), and the DMFT index in the region was 2.6, thus characterizing the area as having a low prevalence of caries. In areas with fluoridated water, the proportion of caries-free children at 12 years was higher than in those without fluoridated water (p = 0.019), and the DMFT was lower (p = 0.001). Prevalence of fluorosis at age 12 was 12.7% in the Sorocaba area and did not pose a public health problem according to the community fluorosis index (CFI).  相似文献   
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Santana RB  Xu L  Chase HB  Amar S  Graves DT  Trackman PC 《Diabetes》2003,52(6):1502-1510
The effect of type 1 diabetes on bone healing and bone formation in standardized craniotomy defects created in BALB/cByJ mice was determined. The hypothesis that advanced glycation end products (AGEs) contribute to diminished bone healing in diabetes was evaluated by assessing for the presence of the receptor for advanced glycation end products (RAGE) by immunohistochemistry in healing craniotomy defects in diabetic animals. The effect of local application of a known RAGE protein ligand, N(epsilon)-(carboxymethyl)lysine (CML)-mouse serum albumin (MSA), on craniotomy defect healing in normal animals was then assessed and compared to the effects of control MSA. Finally, evidence in support of the expression of RAGE mRNA and protein in osteoblastic cells was obtained. The results indicated that craniotomy defects in diabetic animals healed approximately 40% of the degree to which they healed in nondiabetic animals (P < 0.05). RAGE was expressed at higher levels in healing bone tissues in diabetic compared to control animals. Further studies in nondiabetic animals indicated that bone healing was reduced by 63 and 42% in lesions treated with 900 and 90 micro g CML-MSA, respectively, compared to in animals treated with MSA alone (P < 0.05). Evidence for the expression of RAGE was obtained in mouse and rat osteoblastic cultures. These results support the contribution of AGEs to diminished bone healing in type 1 diabetes, possibly mediated by RAGE.  相似文献   
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EDD (E3 isolated by differential display), located at chromosome 8q22.3, is the human orthologue of the Drosophila melanogaster tumour suppressor gene 'hyperplastic discs' and encodes a HECT domain E3 ubiquitin protein-ligase. To investigate the possible involvement of EDD in human cancer, several cancers from diverse tissue sites were analysed for allelic gain or loss (allelic imbalance, AI) at the EDD locus using an EDD-specific microsatellite, CEDD, and other polymorphic microsatellites mapped in the vicinity of the 8q22.3 locus. Of 143 cancers studied, 38 had AI at CEDD (42% of 90 informative cases). In 14 of these cases, discrete regions of imbalance encompassing 8q22.3 were present, while the remainder had more extensive 8q aberrations. AI of CEDD was most frequent in ovarian cancer (22/47 informative cases, 47%), particularly in the serous subtype (16/22, 73%), but was rare in benign and borderline ovarian tumours. AI was also common in breast cancer (31%), hepatocellular carcinoma (46%), squamous cell carcinoma of the tongue (50%) and metastatic melanoma (18%). AI is likely to represent amplification of the EDD gene locus rather than loss of heterozygosity, as quantitative RT-PCR and immunohistochemistry showed that EDD mRNA and protein are frequently overexpressed in breast and ovarian cancers, while among breast cancer cell lines EDD overexpression and increased gene copy number were correlated. These results demonstrate that AI at the EDD locus is common in a diversity of carcinomas and that the EDD gene is frequently overexpressed in breast and ovarian cancer, implying a potential role in cancer progression.  相似文献   
64.
Temporomandibular joint (TMJ) arthritis is a common cause of orofacial pain. In the present study, the modulatory effects of N‐methyl‐d ‐aspartate receptors (NMDA‐Rs) and magnesium were investigated in TMJ arthritis hypernociception. Male Wistar rats received an intra‐articular injection of carrageenan (Cg) in the TMJ, and mechanical hypernociception was measured. The NMDA‐R antagonist, MK‐801, and magnesium chloride (MgCl2) were administered before arthritis induction. Magnesium deficiency was promoted by feeding rats a synthetic magnesium‐free diet for 9 d before injection of Cg. The Cg induced mechanical hypernociception that lasted for 120 h. MK‐801 inhibited this hypernociceptive state. MgCl2 pretreatment prevented Cg‐induced hypernociception and altered the nociceptive threshold in the absence of Cg. Magnesium deficiency increased hypernociception and induced spontaneous hypernociceptive behavior. TMJ arthritis increased the expression of mRNA for all NMDA‐R subunits and immunostaining of phosphorylated NR1 (phospho‐NR1). MgCl2 inhibited expression of NR2B mRNA and phospho‐NR1 immunostaining and increased expression of NR3 mRNA. Magnesium deficiency increased expression of both NR1 and NR3 mRNAs and phospho‐NR1 immunostaining in the trigeminal subnucleus caudalis. We found that magnesium modulates nociceptive behavior and induces NMDA‐R subunit rearrangement in the subnucleus caudalis. The present results may lead to a better understanding of central processing in the nociceptive trigeminal pathway and the development of new approaches to treat orofacial pain with a TMJ origin.  相似文献   
65.
OBJECTIVE: To test the hypothesis that tinnitus begins with outer hair cell dysfunction by recording transient (TEOAE) and distortion product evoked (DPOAE) oto-acoustic emissions in patients with normal hearing with (study group, SG) and without tinnitus (control group, CG). STUDY DESIGN: Case control study. SUBJECTS AND METHODS: SG had 32 patients with pure tone thresholds below 25 dB in the 500 to 8000 Hz interval. CG had 37 age- and gender-matched patients with similar thresholds. All patients had normal tympanograms and stapedial reflexes. TEOAE were recorded with wide band click in continuous mode at 80-dB peak SPL. DPOAE were recorded with f1/f2 = 1.22 and intensities of 65 dB (f1) and 55 dB (f2) SPL. RESULTS: DPOAE were abnormal in 68.4% of SG and in 50% of CG (P = 0.036). TEOAE were abnormal in 70.2% of SG and in 16.10% of CG (P = 0.0001). CONCLUSION: SG had significantly higher prevalence of abnormal TEOAE and DPOAE than CG.  相似文献   
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Dengue is an infectious viral disease transmitted by the Aedes aegypti mosquito, the control of which is complex. In addition, the clinical diagnosis is difficult to perform since it resembles other febrile infections; thus, the development of more effective methods to detect dengue virus (DV) has drawn increasing attention. The present study aimed to develop an impedimetric immunosensor for dengue diagnosis using a screen-printed electrode (SPE) functionalized with polymer films derived from 4-aminophenylacetic acid (4-APA). Data obtained from scanning electron microscopy (SEM) showed the deposition of a uniformly distributed material over the electrode surface. The immunosensor was based on the specific interaction between dengue antigen, NS1 protein, and anti-NS1 antibodies, IgG and IgM. In a characterization study using cyclic voltammetry (CV), the polymer film showed two oxidation peaks at +0.17 and?+?0.35 V in 0.50 M sulfuric acid solution, indicating its adsorption and electroactivity at the SPE surface. Electrochemical impedance spectroscopy (EIS) measurements showed a higher charge transfer resistance (Rct) to the polymer film-modified SPE as compared with the bare SPE, corroborating a previous study. The best rNS1 concentration for immobilization was 1.00 ng/mL, and the immunoreaction time between the antigen (Ag) and the antibody (Ab) was 20 min. Dilutions of positive and negative clinical serum samples were evaluated by EIE, from which it was possible to elucidate, for the positive serum, that the more diluted the serum the greater the Rct. Negative serum also showed an analytical signal, probably due to the presence of non-specific antibodies; however, the generated signal presented values closer to the rNS1 signal, indicating good selectivity of the proposed platform. The experiments were repeated using bare SPE to verify the importance of the polymer film in biosensor construction. No significant difference was observed between these results.
Graphical abstract Proposed schematic for the genosensor development
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