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1.
Five-year clinical performance of porcelain laminate veneers.   总被引:2,自引:0,他引:2  
OBJECTIVE: The clinical performance of porcelain laminate veneers was evaluated at 5 years. METHOD AND MATERIALS: One hundred eighty-six porcelain laminate veneers were placed in 61 patients, aged 18 to 70 years, by a single operator following the same clinical procedure. At the 5-year recall, esthetics, marginal integrity, marginal discoloration, fracture rate, and patient satisfaction were recorded. RESULTS: At recall 98.4% of the veneers were satisfactory without intervention. The retention rate was excellent, the fracture rate was very low, and the maintenance of esthetics was superior. Patient satisfaction was very high. CONCLUSION: Porcelain laminate veneers offer a reliable and effective procedure for the conservative and esthetic treatment of anterior teeth.  相似文献   
2.
The MHC class II molecule H2-A(g7) is the chief genetic determinant in insulin-dependent diabetes mellitus of the non-obese diabetic (NOD) mice. Poor peptide binding ability, as well as presentation of a unique subset of peptides by this molecule was suggested to promote autoimmunity in this strain. However, several laboratories have presented results in favor of an H2-A(g7) molecule that can avidly bind many different peptides. The crystal structures of H2-A(g7) in complex with two different peptides did not completely resolve this issue. To analyze the peptide binding capacity and the motif requirements of H2-A(g7), we eluted natural ligands from purified H2-A(g7) molecules isolated from the H2-A(g7)-transfected M12-C3 cells. A low peptide yield dominated by a few peptide ligands was found. Pool sequencing and alignment of individual ligands on the basis of molecular modeling revealed a peptide-binding motif with basic/aliphatic/small hydrophilic amino acids at relative position 1 (p1), aliphatic amino acids at p4, Ala at p6, and acidic amino acids and Ser/Gly at p9, as well as acidic residues at p10/11. Though weak, the binding of individual ligands, as well as the importance of an acidic C-terminal residue was confirmed by peptide binding studies to isolated H2-A(g7) molecules. Furthermore, the H2-A(g7) molecule incompletely dissociated into its constituent chains in SDS-electrophoresis under nonreducing conditions. This provides additional evidence of its weak affinity for peptides, which probably arises from the combination of beta56His/beta57Ser/beta78Ala and other unique H2-A(g7) residues in contact with the antigenic peptide. These results allow a better understanding of the role of this molecule in the development of autoimmunity and the identification of epitopes relevant to diabetes.  相似文献   
3.
OBJECTIVEThe purpose was to test the hypothesis that the HLA-DQαβ heterodimer structure is related to the progression of islet autoimmunity from asymptomatic to symptomatic type 1 diabetes (T1D).RESEARCH DESIGN AND METHODSNext-generation targeted sequencing was used to genotype HLA-DQA1-B1 class II genes in 670 subjects in the Diabetes Prevention Trial–Type 1 (DPT-1). Coding sequences were translated into DQ α- and β-chain amino acid residues and used in hierarchically organized haplotype (HOH) association analysis to identify motifs associated with diabetes onset.RESULTSThe opposite diabetes risks were confirmed for HLA DQA1*03:01-B1*03:02 (hazard ratio [HR] 1.36; P = 2.01 ∗ 10−3) and DQA1*03:03-B1*03:01 (HR 0.62; P = 0.037). The HOH analysis uncovered residue −18β in the signal peptide and β57 in the β-chain to form six motifs. DQ*VA was associated with faster (HR 1.49; P = 6.36 ∗ 10−4) and DQ*AD with slower (HR 0.64; P = 0.020) progression to diabetes onset. VA/VA, representing DQA1*03:01-B1*03:02 (DQ8/8), had a greater HR of 1.98 (P = 2.80 ∗ 10−3). The DQ*VA motif was associated with both islet cell antibodies (P = 0.023) and insulin autoantibodies (IAAs) (P = 3.34 ∗ 10−3), while the DQ*AD motif was associated with a decreased IAA frequency (P = 0.015). Subjects with DQ*VA and DQ*AD experienced, respectively, increasing and decreasing trends of HbA1c levels throughout the follow-up.CONCLUSIONSHLA-DQ structural motifs appear to modulate progression from islet autoimmunity to diabetes among at-risk relatives with islet autoantibodies. Residue −18β within the signal peptide may be related to levels of protein synthesis and β57 to stability of the peptide-DQab trimolecular complex.  相似文献   
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5.
We have investigated the effect of atorvastatin on the endothelial function of patients with diabetes and subjects at risk for type 2 diabetes in a 12-wk, prospective, randomized, placebo-controlled, double-blind clinical trial. The flow- mediated dilation (FMD; endothelium dependent) and nitroglycerin-induced dilation (endothelium independent) in the brachial artery and the vascular reactivity at the forearm skin were measured. FMD improved in the atorvastatin-treated, at-risk subjects [median (25-75 percentile), 7.2% (2.9-9.6%) at exit visit vs. 6.6% (2.9-9.5%) at baseline; P < 0.05]. A similar improvement of FMD was found in atorvastatin-treated diabetic patients [median (25-75 percentile), 5.6 (3.9-7.9) at exit visit vs. 4.2 (3.2-7.2) at baseline; P = 0.07]. No changes were observed in nitroglycerin-induced dilation and the microcirculation reactivity measurements in either group. In the at-risk group, there was a decrease in the C-reactive protein [median (25-75 percentile), 0.12 mg/dl (0.07-0.27 mg/dl) at exit visit vs. 0.24 mg/dl (0.07-0.35 mg/dl) at baseline; P < 0.05] and TNF alpha [median (25-75 percentile), 2.6 pg/ml (1.8-4.1 pg/ml) at exit visit vs. 4.4 pg/ml (3.6-6.0 pg/ml) at baseline; P < 0.05] in the atorvastatin-treated patients, whereas in the diabetes group, a decrease in endothelin-1 (mean +/- SD, 0.97 +/- 0.29 pg/ml at exit visit vs. 1.19 +/- 0.42 pg/ml at baseline; P < 0.05) and plasminogen activator inhibitor-1 [median (25-75 percentile), 18 ng/ml (9-24 ng/ml) at exit visit vs. 27 ng/ml (7-41 ng/ml) at baseline; P < 0.05] were observed. We conclude that atorvastatin improves endothelial function and decreases levels of markers of endothelial activation and inflammation.  相似文献   
6.
7.
The two main objectives of this study were: (1) to examine the effect of aspirin on the endothelial function in healthy subjects and (2) to examine the effect of deionized water and 5% NaCl as iontophoresis solution vehicles. The skin microcirculation was evaluated at the forearm level of healthy subjects. A laser Doppler scanner was employed to measure vasodilation in response to the iontophoresis of 1% acetylcholine (endothelium-dependent) and 1% sodium nitroprusside (endothelium-independent). In the first experiment, nine healthy subjects were given 500 mg aspirin daily for 3 days. The microvascular reactivity was measured at the beginning and the end of the study. In the second experiment, the response to iontophoresis of acetylcholine and sodium nitroprusside as 1% solutions of deionized water was compared to the responses that were achieved after the iontophoresis of deionized water or 5% NaCl solution. After 3 days of aspirin intake, there were no changes in the vasodilatory response to acetylcholine (endothelium-dependent vasodilation) [81 +/- 11 vs 77 +/- 10 (% of increase over baseline at the beginning vs the end of the study, mean +/- SE), P = NS] or sodium nitroprusside (endothelium-independent vasodilation) (69 +/- 8 vs 64 +/- 12, P = NS). There was also a negligible response after the iontophoresis of 5% NaCl (3 +/- 4) and deionized water (6 +/- 4) in anodal mode (the mode employed for the iontophoresis of acetylcholine). In cathodal mode, employed for the iontophoresis of sodium nitroprusside, the response to 5% NaCl was still negligible but a considerable response was found after the iontophoresis of deionized water. In normal healthy subjects, aspirin administration has no effect on forearm skin microvascular reactivity, including both endothelium-dependent and endothelium-independent vasodilation. In addition, a NaCl solution would be preferable to deionized water as the iontophoresis solution vehicle.  相似文献   
8.
OBJECTIVE: To evaluate the vasodilation induced by topical application of methyl nicotinate (MN) and to compare it with the vasodilatory response to acetylcholine (ACh) and sodium nitroprusside (SNP) in healthy subjects and diabetic neuropathic patients. RESEARCH DESIGN AND METHODS: Ten diabetic patients with peripheral neuropathy (DN) and 10 age- and sex-matched healthy control subjects (C) were enrolled. The vasodilatory response to topical application of 1% MN and a placebo emulsion at the forearm and dorsum of the foot skin at 5, 15, 30, 60 and 120 min was measured using Laser Doppler Perfusion Imaging. The vasodilatory response to iontophoresis of 1% ACh and 1% SNP solutions was also evaluated. RESULTS: The maximal vasodilatory response to ACh, SNP and MN was similar at the forearm and foot level in the diabetic patients. In the control group, the responses to MN, ACh and SNP were similar on the forearm but in the foot, the MN vasodilatory response was higher when compared to the ACh and SNP responses. MN-related vasodilation was present 5 min after the application, reached its peak at 15-30 min and declined to pre-application levels 120 min afterward. CONCLUSIONS: Topical application of MN at the forearm and foot levels of diabetic neuropathic patients results in skin vasodilation that is comparable to the maximal vasodilation that can be induced by iontophoresis of ACh or SNP and lasts for less than 2 h. Further studies will be required to explore the potential of MN to increase blood flow and to prevent diabetic foot problems in clinical practice.  相似文献   
9.
Objectives

To compare the efficacy, acceptance and preference of conventional infiltration technique with a needleless jet anaesthetic device (Comfort-In).

Materials and methods

Non-fearful healthy adult volunteers, aged 19–40 years, were recruited in the Dental School of Aristotle University of Thessaloniki, Greece. Intact maxillary premolars were selected for local anaesthesia. Both techniques were applied sequentially with 35 min time gap on either buccal side on the same day by the same operator. The quadrant and the order of administration were randomly assigned using an online randomization generator. Immediately after administration, at 1, 3, 5, 10, 15, 20, 25 and 30 min, pulp vitality and soft tissue pain reaction tests were performed. Each participant was asked 6 questions in order to assess acceptance. At the end of the session, at 24 h and 7 days, all participants were asked to report any adverse events and their preference.

Results

In 63 volunteers who were successfully followed, 63 teeth received conventional local infiltration and 63 the Comfort-In. Both techniques presented with similar anaesthetic efficacy at 1, 3, 5, 10 and 15 min, whereas the conventional technique was more efficacious at 20 min (p < 0.005). Both presented similar acceptance apart from higher pain/discomfort during administration of Comfort-In (p = 0.002). Significantly higher preference was reported for the conventional technique immediately after the session, at 24 h and at 7 days (p < 0.0005); 19 (30.2%) reported the presence of ecchymosis or lacerations at the Comfort-In site as opposed to 5 (7.9%) with the conventional method (p < 0.0001).

Conclusion

Both techniques showed similar effectiveness. Conventional infiltration was preferred to needleless anaesthesia by non-fearful adult volunteers and was associated with less adverse events.

Clinical relevance

This study enhances the advantages of conventional local anaesthesia.

Trial registration

ISRCTN17400733

  相似文献   
10.
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