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Introduction

The purpose of this study was to identify the 100 top-cited articles published in journals dedicated to endodontology and analyze their characteristics to describe the quality and evolution of research in the field of endodontology.

Methods

The Institute for Scientific Information Web of Knowledge Database and the Journal Citation Report Science Editions were used to retrieve the 100 most cited articles published in journals dedicated to endodontics. The top-cited articles were selected and analyzed with regard to journals, authors, institution, country of origin, publication title and year, number of citations, article type, study design, level of evidence, and field of study.

Results

The top 100 articles were cited between 87 and 554 times. These articles appeared in 4 different journals, with more than half in the Journal of Endodontics, followed by the journals Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology, the International Endodontic Journal, and Endodontics & Dental Traumatology. Forty-eight articles were published between 1990 and 1999. All articles were published in English and primarily originated from the United States (n = 52). The majority of articles were basic science articles (n = 55), followed by clinical research studies (n = 28) and nonsystematic reviews (n = 17). Uncontrolled case series with level IV of evidence and narrative reviews with level V of evidence were the most frequent types of study design. The main topics covered by the top-cited articles were microleakage and endodontic microbiology.

Conclusions

This analysis of citation rates reveals useful and interesting information about scientific progress in the field of endodontics. Basic research and observational studies published in high-impact endodontic journals had the highest citation rates.  相似文献   
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The aim of this study was to evaluate the relative bond strengths of AH-26 and Epiphany sealers to both Resilon and composite resin. Four groups of substrate/bonded sealer combinations were tested: group A, composite resin substrate + Epiphany sealer; group B, composite resin substrate + AH-26 sealer; group C, Resilon substrate + Epiphany sealer; and group D, Resilon substrate + AH-26 sealer. Bond strength was evaluated in shear mode by using a universal testing machine at a crosshead speed of 0.5 mm/min. Statistical analysis (Kruskall-Wallis and Dunn tests) showed that the bond strength of AH-26 to both substrates was significantly greater than the bond strength of Epiphany. Therefore, the monoblock in the root canal might be more effectively achieved by combining Resilon core material with the epoxy resin-based sealer (AH-26) rather than Epiphany sealer.  相似文献   
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The purpose of this study was to compare the microleakage of two root canal sealers, Fibrefill (resin-based sealer) and calciobiotic root canal sealer (CRCS; calcium hydroxide-based sealer), with and without the presence of smear layer. The model used for the measurement of microleakage was a fluid transport model.Sixty human extracted teeth were used in this study. The teeth were divided into four groups and treated as follows. In group A, the smear layer was left intact, and canals were obturated with gutta-percha and Fibrefill. In group B, the smear layer was removed, and canals were obturated with gutta-percha and Fibrefill. In group C, the smear layer was left intact, and the canals were obturated with gutta-percha and CRCS. In group D, the smear layer was removed, and canals were obturated with gutta-percha and CRCS. Microleakage was measured at 7 days, 1 month, and 2 months.The results showed that the Fibrefill groups with and without smear layer leaked significantly less than the CRCS groups at all experimental times. No significant difference was found between the groups of same materials, but the microleakage values were less when the smear layer was removed.  相似文献   
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The objective of the study was to evaluate saliva flow rate, buffer capacity, pH levels, and dental caries experience (DCE) in autistic individuals, comparing the results with a control group (CG). The study was performed on 25 noninstitutionalized autistic boys, divided in two groups. G1 composed of ten children, ages 3–8. G2 composed of 15 adolescents ages 9–13. The CG was composed of 25 healthy boys, randomly selected and also divided in two groups: CG3 composed of 14 children ages 4–8, and CG4 composed of 11 adolescents ages 9–14. Whole saliva was collected under slight suction, and pH and buffer capacity were determined using a digital pHmeter. Buffer capacity was measured by titration using 0.01 N HCl, and the flow rate expressed in ml/min, and the DCE was expressed by decayed, missing, and filled teeth (permanent dentition [DMFT] and primary dentition [dmft]). Data were plotted and submitted to nonparametric (Kruskal–Wallis) and parametric (Student’s t test) statistical tests with a significance level less than 0.05. When comparing G1 and CG3, groups did not differ in flow rate, pH levels, buffer capacity, or DMFT. Groups G2 and CG4 differ significantly in pH (p = 0.007) and pHi = 7.0 (p = 0.001), with lower scores for G2. In autistic individuals aged 3–8 and 9–13, medicated or not, there was no significant statistical difference in flow rate, pH, and buffer capacity. The comparison of DCE among autistic children and CG children with deciduous (dmft) and mixed/permanent decayed, missing, and filled teeth (DMFT) did not show statistical difference (p = 0.743). Data suggest that autistic individuals have neither a higher flow rate nor a better buffer capacity. Similar DCE was observed in both groups studied.  相似文献   
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Accumulating evidence suggests that the stem cell markers CD133 and CD44 indicate molecular subtype in Glioblastoma Multiforme (GBM). Gene coexpression analysis of The Cancer Genome Atlas GBM dataset was undertaken to compare markers of the Glioblastoma Stem-Progenitor Cell (GSPC) phenotype. Pearson correlation identified genes coexpressed with stem cell markers, which were then used to build a gene signature that classifies patients based on a CD133 coexpression module signature (CD133-M) or CD44-M subtype. CD133-M tumors were enriched for the Proneural (PN) GBM subtype compared to Mesenchymal (MES) subtype for CD44-M tumors. Gene set enrichment identified DNA replication/cell cycle genes in the CD133-M and invasion/migration in CD44-M, while functional experiments showed enhanced cellular growth in CD133 expressing cells and enhanced invasion in cells expressing CD44. As with the 4 major molecular subtypes of GBM, there was no long-term survival difference between CD44-M and CD133-M patients, although CD44-M patients responded better to temozolomide while CD133-M patients benefited from radiotherapy. The use of a targeted coexpression approach to predict functional properties of surface marker expressing cells is novel, and in the context of GBM, supports accumulating evidence that CD133 and CD44 protein marker expression correlates with molecular subtype.  相似文献   
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Cardiovascular autonomic neuropathy (CAN) is one of the most serious complications of diabetes and has been weakly linked with left ventricular (LV) diastolic dysfunction. Previous studies that explored this association either suffer from inadequate definition of CAN or have mainly used conventional Doppler or nuclear techniques to investigate LV diastolic function. Tissue Doppler imaging (TDI) has evolved as a new quantitative tool for the assessment of cardiac systolic function, diastolic function, and the hemodynamics of LV filling. We sought to investigate conventional and TDI-derived indexes of LV systolic and diastolic function in type 1 diabetic patients with and without CAN and also in normal control subjects. Our findings suggest that the presence of CAN seems to have an additive effect on LV diastolic dysfunction in type 1 diabetes.  相似文献   
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PurposeThe aim of this study was to evaluate the effects of a dietary supplement containing primarily an extract of salmon's milt (semen) on symptoms and blood levels of proinflammatory molecules in patients with fibromyalgia syndrome (FMS), a chronic, painful musculoskeletal disease without a distinct pathogenesis or treatment. We recently reported increased serum levels of the proinflammatory molecules substance P (SP) and tumor necrosis factor (TNF) in patients with FMS as compared to those in normal controls.MethodsThis prospective, open-label study was conducted in patients with FMS (n = 87; 80 women, 7 men; age range, 18–80 years) selected from 2 clinical centers in Spain. Patients were administered the supplement and were evaluated at weeks 1 (before treatment), 4, 8, and 12 (end of treatment) for clinical parameters of functioning, fatigue, and pain, as well as overall impression. Patients were directed to take 1 capsule per day in the morning for the first 4 weeks, followed by 1 capsule in the morning and 1 capsule in the evening for the remaining 8 weeks. Differences in symptom scores in patients with FMS between weeks 1 and weeks 4, 8, and 12 were evaluated using ANOVA. Blood was obtained and serum separated in patients with FMS at 1 and 12 weeks and in a separate population of healthy controls (n = 20; 15 women, 5 men; age range, 25–65 years). Serum levels of SP and TNF were measured in patients with FMS at 1 and 12 weeks and in healthy controls by ELISA. TNF and SP levels in patients with FMS were compared between weeks 1 and 12, as well as between patients with FMS and untreated controls, using the Mann–Whitney U test.FindingsClinical parameters of functioning, fatigue, and pain, as well as overall impression, were improved significantly at 4 weeks as compared to 1 week and remained unchanged for the duration of the study (all, P < 0.0001). Serum TNF and SP levels were significantly elevated at 1 week in patients with FMS compared to controls and were decreased significantly at 12 weeks as compared to 1 week (all, P < 0.0001).ImplicationsOur findings indicate that this dietary supplement may significantly improve symptoms in patients with FMS. This is the first time to our knowledge that any molecule has been reported to be associated with a reduction in serum SP level. Consequently, the supplement or its hypothesized main active ingredient, spermine, may be developed as a novel treatment approach to FMS or other neuroinflammatory conditions. ClinicalTrials.gov identifier: NCT03911882.  相似文献   
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