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991.
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993.
Placental protein 13 (PP13) is a galectin expressed by the syncytiotrophoblast. Women who subsequently develop preterm pre-eclampsia have low first trimester maternal serum PP13 concentrations. This study revealed that third trimester maternal serum PP13 concentration increased with gestational age in normal pregnancies (p < 0.0001), and it was significantly higher in women presenting with preterm pre-eclampsia (p = 0.02) and hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome (p = 0.01) than in preterm controls. Conversely, placental PP13 mRNA (p = 0.03) and protein, as well as cytoplasmic PP13 staining of the syncytiotrophoblast (p < 0.05) was decreased in these pathological pregnancies compared to controls. No differences in placental expression and serum concentrations of PP13 were found at term between patients with pre-eclampsia and control women. In contrast, the immunoreactivity of the syncytiotrophoblast microvillous membrane was stronger in both term and preterm pre-eclampsia and HELLP syndrome than in controls. Moreover, large syncytial cytoplasm protrusions, membrane blebs and shed microparticles strongly stained for PP13 in pre-eclampsia and HELLP syndrome. In conclusion, parallel to its decreased placental expression, an augmented membrane shedding of PP13 contributes to the increased third trimester maternal serum PP13 concentrations in women with preterm pre-eclampsia and HELLP syndrome.  相似文献   
994.
Jia W  Qiu M  Sun X  Qiu Y  Su M 《Advances in therapy》2004,21(4):238-246
During the process of developing a slow-release formulation of indapamide, researchers created a drug-containing pellet coated with Eudragit RS100 (Rohm GMbH & Co. KG, Darmstadt, Germany) to control the rate at which the drug was released. The two main variables were the agglomerants used in the pellet preparation and the amount of Eudragit RS100 used to coat them. The optimal outcome was indicated by the greatest number of drug-containing pellets recovered through an 18- to 24-mesh sieve and a satisfactory 24-hour release curve. The kinetics of dissolution fit the Higuchi kinetics model. Stability tests of the drug pellets showed no notable changes in the rate of drug release, related substances (mean byproducts or impurities from interactions or decompositions), and drug content.  相似文献   
995.
Purpose Six impression techniques were evaluated using tapered and square impression copings. Materials and Methods The absolute distortion was measured using a cast metal impression tray with fiduciary reference points external to the impression material. Measurements of the x, y, z coordinates on the master cast and the impressions were directly made with a travelling digitizing microscope. The difference between the coordinates of each of six sites in the impression and the corresponding reference site were compared. Results There was no significant difference between the techniques for the square copings but that there was a significant loss of accuracy in the z-axis with the tapered copings. Conclusions No significant differences were noted.  相似文献   
996.
997.
Denture stomatitis is a common inflammatory condition affecting the mucosa underlying complete dentures. It is associated with denture microbial biofilm, poor denture hygiene, poor denture quality, and nocturnal denture use. Numerous treatment methodologies have been used to treat stomatitis; however, a gold standard treatment has not been identified. The aim of this systematic review is to report on the current knowledge available in studies representing a range of evidence on the treatment of denture stomatitis.  相似文献   
998.
Purpose: The aim of this study was to examine early changes in retentive values of implant overdenture attachments during multiple pulls.
Materials and Methods: Two implant attachment systems (Hader bar and clip, Locator system) were used in this study. The experimental groups were divided into yellow Hader clips, white Locator attachments, and green Locator attachments. Each group consisted of 21 matrix attachments. The attachments were placed into a custom-made acrylic resin block seated passively on another acrylic block containing a Hader bar or two Locator abutments with different angulations. Each attachment was subjected to 20 consecutive pulls using a universal testing machine. The peak load-to-dislodgement of the attachments after each pull was documented, and the percent reduction of the peak load-to-dislodgement was calculated. One-way ANOVA and Tukey's honestly significant difference test were used for data analyses. A p ≤ 0.05 was considered significant.
Results: There was a significant difference in the percent reduction in peak load-to-dislodgement between the attachments after the first pull ( p = 0.005) and after the final pull ( p = 0.0001). The yellow Hader clips exhibited the least percent reduction in peak load-to-dislodgement (6.50 ± 3.59%) after the first pull, followed by the white Locator attachments (8.60 ± 4.42%); the green Locator attachments exhibited the greatest reduction (11.05 ± 4.94%).
Conclusion: The results of this in vitro study demonstrate that retentive values of the Locator attachments are reduced significantly after multiple pulls. Although this reduction might not be noticeable to the patient, it is recommended that the clinician place and remove the overdenture multiple times before delivery.  相似文献   
999.
Purpose: The purpose of this longitudinal study was to evaluate the success of bovine bone and calcium sulfate (CaSO4) as sinus augmentation material with osteotome maxillary sinus lift. Materials and Methods: Thirty‐one osteotome sinus lift procedures were performed for 18 healthy patients (7 males and 11 females). A mixture of bovine bone and CaSO4 (ratio, 4:1) was used as sinus augmentation material with simultaneous implant placement. Implants were loaded 4 to 5 months postimplant surgery. Cases were followed for an average of 23.4 months postloading (range, 12–60 months). Results: The mean age of the study group was 49.7 ± 10.66 years. The residual height of the alveolar ridge ranged from 5.5 to 11 mm (mean, 8.16 ± 1.52 mm). Four to 5 months after implant placement, the x‐ray showed a 1.5 to 5 mm apical shift of the sinus floor (mean, 3.47 ± 0.97 mm), which was maintained to the end of the evaluation period. At 12 months postloading, crestal bone loss ranged from 0.5 to 1.5 mm (mean, 0.87 ± 0.26 mm), and pocket depth ranged from 2 to 4 mm (mean, 2.9 ± 0.67 mm). No significant change in crestal bone loss or pocket depth was noticed afterward. Conclusion: Bovine bone plus CaSO4 can be used successfully as a sinus augmentation material with osteotome sinus elevation. The use of CaSO4 significantly improved the handling properties of bovine bone and helped to stabilize the bone graft particles during healing.  相似文献   
1000.

Introduction

The purpose of this pilot study in a cadaver model was to compare 2 different shaping techniques regarding the induction of dentinal microcracks.

Methods

Three lower incisors from each of 6 adult human cadaver skulls were randomly distributed into 3 groups: the control group (CG, no instrumentation), the GT group (GT Profile hand files; Dentsply Tulsa Dental, Tulsa, OK), and the WO group (WaveOne; Dentsply Tulsa Dental). In the GT group, manual shaping in a crown-down sequence with GT Profile hand files was performed. In the WO group, Primary WaveOne files were used to the working length. Teeth were separated from the mandibles by careful removal of soft tissue and bone under magnification. Roots were sectioned horizontally at 3, 6, and 9 mm from the apex using a low-speed saw. Color photographs at 2 magnifications (25× and 40×) were obtained. Three blinded examiners registered the presence of microcracks (yes/no), extension (incomplete/complete), direction (buccolingual/mesiodistal), and location. Data were analyzed with chi-square tests at P < .05.

Results

Microcracks were found in 50% (CG and GT) and 66% (WO) of teeth at 3 mm, 16.6% (CG) and 33.3% (GT and WO) at 6 mm, and 16.6% in all 3 groups at 9 mm from the apex. There were no significant differences in the incidence of microcracks between all groups at 3 (P = .8), 6 (P = .8), or 9 mm (P = 1). All microcracks were incomplete, started at the pulpal wall, and had a buccolingual direction.

Conclusions

Within the limitations of this pilot study, a relationship between the shaping techniques (GT hand and WaveOne) and the incidence of microcracks could not be shown compared with uninstrumented controls.  相似文献   
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