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61.
The LG HIV Ag-Ab Plus, a new fourth generation diagnostic assay for HIV infection, was evaluated in comparison to the Enzygnost HIV Integral, an established fourth generation HIV assay. The LG assay showed 100% sensitivity with 109 samples with anti-HIV-1, anti-HIV-2 or anti-HIV-1 group O reactivity. It also detected correctly all 51 positives on three BBI performance panels, slightly outperforming the Enzygnost HIV Integral, which detected 50. The specificity of the LG HIV Ag-Ab Plus was 99.9% with 999 sera from healthy blood donors, which was slightly inferior to the performance of the Enzygnost HIV Integral, which had 100% specificity. The LG assay showed 100% specificity with 81 specimens with underlying diseases including hepatitis B, demonstrating a low risk of cross-reactivity with other infections. The reduction of the diagnostic window by the LG HIV Ag-Ab Plus, compared to a third generation HIV assay, was 6.3 days. The LG assay also showed sufficiently high intra-person and inter-person reproducibility. The overall performance of this new fourth generation HIV assay was adequate for screening and diagnosis of HIV infection.  相似文献   
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63.

Background:

In heart failure with preserved ejection fraction (HFPEF), physiological abnormalities are not solely restricted to diastolic function. Because the tissue Doppler imaging (TDI)‐derived myocardial performance index (MPI) offers the advantage of recording systolic and diastolic tissue velocity simultaneously in the same cardiac cycle, this study aimed to determine whether TDI‐MPI is an informative index for assessing HFPEF, compared with conventional echo parameters.

Hypothesis:

In patients with HFPEF, TDI‐MPI would be an independent predictor for adverse cardiac events.

Methods:

Among 408 patients who had diastolic dysfunction without heart failure (HF) or HFPEF, cardiac function was evaluated by mitral flow (MF) or TDI‐MPI. During the median follow‐up of 32 months, clinical outcomes, which were defined as the composite of cardiovascular death and admission for HF, were assessed.

Results:

Mean MF and TDI‐MPI were significantly greater in the HFPEF group. TDI‐MPI rather than MF had a significant correlation with N‐terminal pro‐brain natriuretic peptide level. The area under the receiver operating characteristic curve of TDI‐MPI for the detection of HFPEF was 0.86. With regard to clinical outcomes, 31 events were identified during follow‐up periods. On a multivariate analysis, TDI‐MPI >0.66 was the best prognostic predictor of events and provided incremental predictive value.

Conclusions:

Compared to MF‐MPI, TDI‐MPI may be a more useful parameter for the evaluation of patients with HFPEF. © 2011 Wiley Periodicals, Inc. The authors have no funding, financial relationships, or conflicts of interest to disclose.  相似文献   
64.
65.

Objective

De novo cancers of head and neck area in solid organ transplantation recipients show standardized incidence ratio (SIR) of 3.8. Immunosuppression following transplantation is suggested to play as a crucial factor in pathogenesis of secondary malignancy. Prognosis of head and neck cancer arising in solid organ transplantation recipients is proven to have poor prognosis. The incidence, risk, prognosis, and survival of de novo malignancy of head and neck area in solid organ transplantation recipients in single-tertiary medical center followed up for 20 years.

Methods

A retrospective medical record review of the patients who received solid organ transplantation in Asan Medical Center from 1997 to 2016 was conducted. Patients confirmed as de novo malignancy in the head and neck area after organ transplantation were included, and presented as in the case-series format. Patients with previous history of head and neck malignancy, irradiation history of head and neck area, cutaneous malignant lesion, hematopoietic malignant lesion, malignancy of thyroid and parathyroid gland and metastatic lesions newly developed in head and neck area were excluded. The incidence of head and neck malignancy in South Korea were reviewed from the National Cancer Information Center of South Korea. For the statistical analysis, standardized incidence ratio (SIR) was obtained with 95% confidence interval.

Results

Solid organ transplantation recipients show 20 times higher incidence of de novo cancer of head and neck area compared to general population. Of 13 de novo head and neck malignancy arising after solid organ transplantation, 2 (15.4%) patients were unable to withstand definitive management due to poor general condition. 2 (15.4%) patients had loco-regional recurrence, 1 (7.7%) patient with distant metastasis, and 3 (23.1%) patients died of cancer progression.

Conclusion

Immunosuppression following solid organ transplantation gives a twenty-fold increased risk for the development of de novo head and neck cancer. A more precise and frequent checkup on head and area should be planned, suggesting a multi-disciplinary approach in combination with organ transplantation team.  相似文献   
66.
A 79-year-old man was followed in our hospital for 4 years following primary percutaneous coronary intervention at another hospital to deploy two stents at the left anterior descending coronary artery for acute myocardial infarction (AMI). At the first visit in our hospital, echocardiography revealed a small ventricular septal defect (VSD, 0.8 to 1.0 cm) in the apicoseptal wall with an aneurysm that was probably the result of the AMI. There was no hemodynamic decompensation, and because the patient refused surgical correction we instead placed him under close follow-up observation in the outpatient clinic. A second follow-up echocardiography 6 months later still revealed a VSD. However, after 3 years the VSD murmur was no longer audible and follow-up echocardiography showed the defect to be nearly closed .  相似文献   
67.
OBJECTIVE: To test the antiadherent and antibacterial properties of surface modification of orthodontic wires with photocatalytic titanium oxide (TiO(2)). MATERIALS AND METHODS: TiO(2) was coated on the surface of the orthodontic wires by a sol-gel thin film dip-coating method. Bacterial adhesion to the wires was evaluated by the weight change of the wires. The antibacterial activity of the surface-modified orthodontic wires was demonstrated by the dilution agar plate method for Streptococcus mutans and spectrophotometry for Porphyromonas gingivalis. RESULTS: The orthodontic wires coated with the photocatalytic TiO(2) showed an antiadherent effect against S. mutans compared with the uncoated wires. The bacterial mass that bound to the TiO(2)-coated orthodontic wires remained unchanged, whereas that of the uncoated wires increased by 4.97%. Furthermore, the TiO(2)-coated orthodontic wires had a bactericidal effect on S. mutans and P. gingivalis, which cause dental caries and periodontitis, respectively. The antiadherent and antibacterial mechanisms of TiO(2) to break down the cell wall of those bacteria were revealed by scanning electron microscopy. CONCLUSION: The surface modification of orthodontic wires with photocatalytic TiO(2) can be used to prevent the development of dental plaque during orthodontic treatment.  相似文献   
68.
The aims of this study were to identify microorganisms on the surface of gutta-percha (GP) cones using a polymerase chain reaction (PCR) and to evaluate the sterilization effect of 5.25% sodium hypochlorite (NaOCl), 2% chlorhexidine (CHX), and ChloraPrep on these bacteria. Alterations of the surface texture and physical properties of GP cone after chemical sterilization were compared. A total of 150 GP cones were randomly selected in endodontic clinics, and a PCR assay was performed to identify the contaminating microorganisms. After inoculation with the same microorganisms followed by drying for 1 day, the GP cones were immersed in the three chemical disinfectants. The sterilization effects were assessed by measuring the turbidity and through subculturing. The changes in surface texture were observed by scanning electron microscopy, and Instron 5500 (Instron Corp, Canton, MA) was used to measure the tensile strength and elongation rate of the GP cones after chemical sterilization. Statistical analysis was performed. Results indicate that 19.4% of GP cones from the clinic were contaminated, and all the species belonged to the genus Staphylococcus. Three chemical disinfectants were all effective in the rapid disinfection of GP cones against Staphylococcus spp, and 1-minute immersion of the GP cones was adequate for disinfection. Microphotographs of the NaOCl-soaked cone showed a cluster of cuboidal crystals. The tensile strength between the NaOCl- and CHX-soaked groups was significantly different (p<0.05), but there was no significant difference between the NaOCl- and ChloraPrep-soaked groups (p>0.05). All disinfectants significantly increased the elongation rate of the GP cones compared with fresh GP cones (p<0.05), especially in the ChloraPrep (Medi-flex, Leawood, KS). These results show that the three chemical disinfectants are effective agents for the rapid sterilization of GP cones. However, further research will be needed to determine the clinical relevance of the changes in physical properties.  相似文献   
69.
Omega-3 fatty acids, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have anti-inflammatory properties and have recently been considered essential factors for maintaining muscle health. This study aimed to investigate the relationship between omega-3 fatty acid intakes and sarcopenia by assessing grip strength in elderly Koreans who are at risk of sarcopenia. This study was conducted on 5529 individuals (2449 males and 3080 females) aged ≥65 years from the raw data of the Korea National Health and Nutrition Examination Survey 2015–2019. In this study, we analyzed the association between EPA and DHA intake, calculated from a 24-h recall method data, and grip strength, a diagnostic criterion for sarcopenia. The cut-off values for low grip strength were <26 kg for males and <18 kg for females, which were set for the Asian population. The results indicated that elderly females consuming EPA and DHA below the adequate intake (AI) had significantly lower grip strength (p < 0.0001) and, had a higher percentage contribution from carbohydrates, but a significantly lower percentage contribution from protein (p < 0.0001), compared to elderly females consuming EPA and DHA at or above the AI. In addition, after adjusting for confounding factors, the odds of low grip strength were 0.777 times lower among elderly females consuming EPA and DHA at or above the AI than those consuming EPA and DHA below the AI (95% confidence interval: 0.616–0.979, p = 0.0322). These results suggest that sufficient intake of EPA and DHA is pivotal to mitigate a reduction in grip strength and to improve the quality of nutrient intake among elderly females.  相似文献   
70.
You SY  Kim HC  Bae KS  Baek SH  Kum KY  Lee W 《Journal of endodontics》2011,37(9):1296-1300

Introduction

Recently, root canal shaping with reciprocating motion has been postulated to reduce the possibility of unexpected file fractures. However, there has been little information on the shaping capability of this reciprocating motion preparation technique. Therefore, the purpose of this study was to evaluate the shaping ability of reciprocating motion when compared with continuous rotation motion in curved root canals.

Methods

The mesiobuccal and distobuccal canals of 20 extracted maxillary molars with curvatures of 20-45 degrees were instrumented with a series of ProTaper rotary files. The canals in the continuous rotation motion (CM) group (n = 20) were prepared by using continuous rotation with pecking motion, whereas the canals in the reciprocating motion (RM) group (n = 20) were prepared with reciprocating motion (clockwise 140 degrees and counterclockwise 45 degrees). Basic geometric parameters such as curvature, root canal volume, surface area, and structure model index (SMI) before and after canal shaping were evaluated by using micro-computed tomography. The degrees and directions of transportation were also measured, and statistical analysis was carried out with one-way analysis of variance and Tukey post hoc tests.

Results

There were no significant differences between the 2 groups in canal curvature, volume, surface area, and SMI categories measured before preparation (P > .05). Changes in curvature, root canal volume, surface area, and SMI were not affected by the instrumentation technique used (P > .05). There were no significant differences in the degrees and directions of transportation between CM and RM groups (P > .05).

Conclusions

The application of reciprocating motion during instrumentation did not result in increased apical transportation when compared with continuous rotation motion, even in the apical part of curved canals. Reciprocating motion might be an attractive alternative method to prevent procedural errors during root canal shaping.  相似文献   
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