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51.

Introduction

The aim of this study was to present ultrasound imaging (UI) techniques as promising and safe tools for the follow-up of root-end surgery (RES) in vivo.

Methods

The study included 8 patients who underwent RES. All were followed up using UI at 1 week, 1 month, 2 months, 3 months, and 6 months (if necessary) after RES. The bony crypt was defined on the ultrasound image, and the following observations were made during follow-up: cortical bone interruption and surface area measurement of the residual echoic bony crypt image.

Results

In all cases, the hypoechoic image became hyperechoic, indicating gradual bone healing of the crypt. Compared with baseline, at 3 months a remaining cortical opening of 51.2% (±12.6%) and a bony crypt surface area of 24.3% (±10.8%) was detected for all patients. For 50% of the patients, the echographic follow-up ended at 3 months because the ultrasound waves could no longer enter the bony crypt. For 4 patients who attended the 6-month recall, a remaining cortical disruption of 43.2% (±9.9%) and a bony crypt surface area of 17.2% (±7%) compared with the baseline was noted.

Conclusions

UI is a promising follow-up tool for RES. It helps clinicians understand the initial stages of bone healing, allows close healing monitoring, and is radiation free.  相似文献   
52.

Introduction

A regenerative endodontic procedure (REP) is a biologically based treatment to functionally replace the pulp of infected immature permanent teeth. The purpose of this retrospective case series was to assess the outcome of REPs of infected immature permanent teeth in terms of periapical bone healing (PBH), root development (RD), and pulp vitality.

Methods

Five patients (1 tooth/patient) who had undergone a REP based on the cell homing concept were recalled 3, 6, 12, 24, and 36 months postoperatively. At each recall session, clinical and periapical radiographic (PR) investigations were performed. Cone-beam computed tomographic (CBCT) imaging was taken before and 36 months after REPs. Qualitative and quantitative PR assessments were performed on the teeth that underwent REPs. Quantitative CBCT analyses were performed on the teeth that underwent REP and contralateral teeth.

Results

At each recall session, all teeth were asymptomatic but reacted negatively on carbon dioxide snow and electrical pulp testing. All teeth that underwent a REP showed complete PBH and further RD on PR and CBCT assessments when comparing the baseline with the final recall radiographs. CBCT analyses indicated increases in root hard tissue volume and RL for all teeth that underwent a REP, but they were 5 and 3 times less, respectively, than the contralateral teeth. The postoperative CBCT images presented bone ingrowth inside the root canal, calcification, or nonuniform RD.

Conclusions

Thirty-six months after the REPs (based on the cell homing concept), this RCS resulted radiographically and clinically in functional and asymptomatic teeth with complete PBH and continued reparative RD. CBCT quantitative measurements and qualitative root development observations are more reliable and accurate than PR analysis.  相似文献   
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Objectives To investigate the CYP1A2 genotype-phenotype relationship and to compare CYP1A2 genetic polymorphisms and enzyme activity in terms of the effect of smoking and oral contraceptive (OC) use in Swedes and Koreans. Methods CYP1A2 enzyme activity was determined in 194 and 150 healthy Swedish and Korean subjects, respectively, on the basis of the 4-h plasma paraxanthine/caffeine (17X/137X) ratio determined using high-performance liquid chromatography. Genotyping for the −3860G>A, −2467delT, −739 T>G, −729 C>T, −163C>A and −3113A>G polymorphisms was performed by PCR-restriction fragment length polymorphism analysis. Results The mean 17X/137X ratio was 1.54-fold higher in Swedes than in Koreans (mean difference: 0.16; 95% CI of the mean difference: 0.12, 0.20; p < 0.0001). Smokers had a significantly higher 17X/137X ratio (higher CYP1A2 activity) than non-smokers, while Swedish OC users had a significantly lower 17X/137X ratio than non-users (mean difference: 0.31, 95% CI of the mean difference: 0.23, 0.39; p < 0.0001). No effect of gender differences on enzyme activity was observed. Four known (CYP1A2*1A, *1D, *1F, and *1L) and two novel haplotypes (CYP1A2*1V and CYP1A2*1W) were found. CYP1A2*1K was rare in Swedes and absent in Koreans. No significant genotype-phenotype relationship was observed, with the exception of CYP1A2*1F in Swedish smokers, where it was associated with higher enzyme inducibility (p = 0.02). Koreans displayed a significantly lower mean 17X/137X ratio than Swedes having the same CYP1A2 genotype, smoking habit and OC use. Conclusions We found significant differences in CYP1A2 enzyme activity between Swedes and Koreans that could not be explained by environmental factors or the CYP1A2 haplotypes examined, despite differences in allele frequencies. None of the investigated CYP1A2 haplotypes are critical in inducing variations in enzyme activity, with the exception of CYP1A2*1F.  相似文献   
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Recent reports have indicated different effects of immunostimulatory sequences containing CpG-Oligodeoxynucleotides (ODN) on various immune cells. However, the exact role of CpG-ODN in the human gut is unclear. In the present study, we assessed potential effects of CpG-ODN on non lymphoid cell (intestinal epithelial cell line HT-29) on a dose-response and time-course basis. Intestinal epithelial cell line HT-29 was treated with CpG-ODN (CpG 2006) and lipopolysaccharide (LPS) at 5, 10, 25, 50 microg/ ml and 1, 5, 10 microg/ ml concentrations, respectively. Following treatments, dose- response and time-course cytotoxicity using a colorimetric method, Metaloproteinase-2 (MMP-2) activity (using gelatin zymography) and apoptosis (using annexin-v flowcytometry method) assays were performed. Chloroquine treatment was also used for its inhibitory effect on endosomal acidification process to verify specific CpG-ODN and Toll Like Receptor 9 (TLR9) interactions. Cytotoxicity analysis of CpG-ODN showed that CpG-ODN increased significantly the proliferation of CpG-ODN treated cells, as compared to untreated cells, at concentrations of 10-25 microg/ml (p < 0.05). Overall MMP-2 activity analysis showed significant differences between treated and untreated cells. However, minimal changes were observed when MMP-2 activity was assessed per cell. Moreover, CpG-ODN treated cells demonstrated an increasing apoptosis rate of 0.8 %, 6.46 % and 14.21% at concentrations of 5, 10, 25 microg/ml, respectively. Collectively, our data indicated that intestinal epithelial cell line HT-29 is highly responsive to CpG effect in vitro and exhibits modified activities. The direct CpG-ODN and TLR-9 interactions in HT-29 cells could provide new approaches in malignant tumor therapeutic strategies.  相似文献   
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Matrix metalloproteinases (MMP) are ubiquitous enzymes involved in extracellular matrix remodeling, and as a consequence in a number of physiological and pathological states, including development, wound healing and cancer. A crucial feature of cancer progression and metastasis is the disruption of extracellular matrix, and spreading of proliferating cancer cells. Modulation of MMP is a main target of cancer research. Using the mouse fibrosarcoma cell line WEHI 164, producing high amounts of MMP-2, we investigated whether we could modulate its production. We report that MMP-2 is under the control of nitric oxide (NO)/nitric oxide synthase (NOS) system. In addition, we show that NOS activity is controlled by opioids in a non-opioid receptor-related manner. Finally, we provide evidence that morphine, when administrated at low, non-toxic concentrations (<10(-9) M) attenuates MMP-2 activity. We conclude that, as morphine is able to decrease metalloproteinase activity via the NO/NOS system, it may have a place in the treatment of several sarcomas including fibrosarcoma.  相似文献   
58.
There are increasing data on novel tumor markers such as gelatinase A, which play a key role in tissue invasion and metastasis. Since prostate cancer is one of the common malignancies, we designed a simple and applicable Indirect Hemagglutination (IHA) test for determination of total gelatinase A in serum samples. In this study, we have analyzed the circulating form of gelatinase A (MMP-2) in patients suffering from either benign prostate hyperplasia (n= 54) or prostate cancer (n= 26) and normal individuals as control (n= 26). The gelatinolytic activity was determined by zymography followed by densitometric analysis. PSA was quantified by using a standard ELISA technique. Correlation of densitometric analysis of gelatinase A activity and IHA titer was significant at 0.01 level (p< 0.01, r = 0.916). Correlation of PSA and IHA titer was significant at 0.01 level (p< 0.01, r = 0.746). Border line IHA titer in patients with prostate cancer was 512 +/- 1 tube titer, in benign prostate hyperplasia patients was 128 +/- 1 tube titer, and the titer in normal individuals was 8 +/- 1 tube titer. These results demonstrate that IHA compared to zymography may be a better and simpler procedure in monitoring and screening patients with prostate cancer.  相似文献   
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