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排序方式: 共有1121条查询结果,搜索用时 15 毫秒
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镍铬合金烤瓷修复体394件中远期修复效果回顾性分析 总被引:2,自引:1,他引:1
目的:了解镍铬合金烤瓷修复体的中远期修复效果。方法:对我科1995年7月~2005年3月具有完整病历记载并能正常复诊的312例(394件)镍铬合金烤瓷修复体的临床资料进行了回顾性分析。结果:镍铬合金烤瓷修复体3年以上成功率为96.2%,5年以上成功率为92.9%,牙龈炎症、松动脱落、瓷崩是镍铬合金烤瓷修复体失败的3种主要表现。结论:为确保镍铬合金烤瓷修复体的中远期疗效,应从适应证的选择、固位体的设计、基牙制备、烤瓷工艺等方面严格把关。 相似文献
3.
Therapeutic Consequences of Variation in Intraarterial Pressure Measurements After Iliac Angioplasty
Eric Tetteroo Cees Haaring Andries D. van Engelen Yolanda van der Graaf Willem P.T.M. Mali 《Cardiovascular and interventional radiology》1997,20(6):426-430
Purpose: To assess the accuracy of intraarterial measurement of transstenotic pressure gradients for the detection of hemodynamically
suboptimal iliac angioplasty.
Methods: In 14 patients, referred for diagnostic angiography, mean pressure gradients in the aorta and iliac artery were obtained
twice, using a double-sensor pressure catheter. Additional iliac measurements were performed during pharmacologically induced
flow augmentation. Repeatability was assessed by calculation of the mean difference plus standard deviation (MD ± SD) and
repeatability coefficient (2 × SD). These results were extrapolated to 137 iliac angioplasty procedures with secondary stenting
where there was a residual pressure gradient > 10 mmHg.
Results: MD ± SD for repeated measurements at rest and during flow augmentation were 0 ± 2 mmHg and 1 ± 3 mmHg, respectively. Repeatability
coefficients were 3 and 6 mmHg. Mean pressure gradients after hemodynamically insufficient angioplasty were 8 ± 7 mmHg at
rest and 17 ± 5 mmHg following vasodilatation. Inaccurate pressure recordings may have led to inappropriate stent placement
in less than 2.5%, and inappropriate denial of stent placement in less than 5% of the lesions.
Conclusion: Variability of intraarterial pressure measurements has little consequence in the detection of hemodynamically significant
stenosis after angioplasty.
Received: 0/00/00/Accepted: 0/00/00 相似文献
4.
Color Stability of Dry Earth Pigmented Maxillofacial Silicone A-2186 Subjected to Microwave Energy Exposure 总被引:2,自引:0,他引:2
Sudarat Kiat-amnuay DDS MS ; Dennis A. Johnston PhD ; John M. Powers PhD ; Rhonda F. Jacob DDS MS 《Journal of prosthodontics》2005,14(2):91-96
PURPOSE: The purpose of this study was to measure spectrophotometrically the color stability of pigmented A-2186 silicone maxillofacial elastomer with 10% by volume of titanium white dry earth opacifier before and after exposure to microwave energy over a simulated 1.5-year period of microwave sterilization. Materials AND METHODS: A-2186 silicone elastomer opacified with titanium white dry earth pigment, pigmented with 5 cosmetic dry earth pigment colors [no pigment (control) group (Pc), red (Pr), yellow ochre (Py), burnt sienna (Po), and a mixture of Pr + Py + Po color group (P3)], was used in this study. Each of the 5 experimental groups consisted of 5 specimens. All specimens were placed in a 250 ml glass beaker filled with 150 ml of water (replenished for each microwave exposure). An exposure of 6 minutes was used 18 times (simulating 1.5 years of microwave sterilization with one 6 minute exposure monthly). Reflectance values were measured by spectrophotometer. Three- and two-way analyses of variance with repeated measures were performed for the color difference (DeltaE*) with the factors of group/color/months, and group/months, respectively. Means were compared by Tukey Honest Significant Difference (HSD) multiple range test calculated at the 0.05 level of significance using SPSS. RESULTS: The trained human eye can detect color changes (DeltaE*) greater than 1.0. Most DeltaE* values of the red pigment group at all intervals and the mixed pigment group at 15- and 18- month intervals increased significantly greater than 1.0 (p < 0.001) compared with the control group. Yellow and burnt sienna groups remained the most color stable over time with DeltaE* values below 0.35. CONCLUSIONS: Lack of color stability of red dry earth pigmented A-2186 silicone maxillofacial elastomers was clinically significant after 12-month exposure to microwave energy as compared with yellow, burnt sienna, and opacified A-2186 dry earth pigments. 相似文献
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Leonora Q. Schwandt Henri-Jacques Tjong-Ayong Ranny van Weissenbruch Henny C. der Mei Frans W. J. Albers 《European archives of oto-rhino-laryngology》2006,263(6):518-523
Tracheoesophageal voice prostheses need to be replaced due to increased airflow resistance or retrograde leakage of fluid into the trachea as a consequence of biofilm formation. Previous in vitro studies show a change of aerodynamic features of biofilm covered voice prostheses after removal of the prostheses out of the patient. To assess these changes in an in situ situation, aerodynamic characteristics were measured within 45 patients at the beginning and at the end of the wearing process of the Provox 2 voice prosthesis. As a consequence, the influence of biofilm formation on aerodynamic characteristics can be evaluated. In the majority of cases, leakage through the prosthesis was the reason for replacement. No differences were found in the total flow, volume range and intratracheal pressure (ITP) of the voice prostheses measured. The airflow resistance of biofilm covered prostheses was significantly reduced compared to new clean prostheses. However, no correlation was found between the extent of biofilm and the different aerodynamic features measured. Biofilm formation on the Provox 2 is responsible for both reduction in airflow resistance and leakage through the prosthesis by deterioration of the silicone rubber material. 相似文献
7.
José I. Bilbao Manuel Ruza Jesús M. Longo Francisco Mansilla Antonio Picardi Vanessa de Villa Fernando Pardo Jesús Sola Jorge Quiroga 《Cardiovascular and interventional radiology》1994,17(4):210-213
Posttransplant lymphoproliferative disorders are infrequent tumors related to chronic immunosuppressive therapy. We present a liver transplant recipient who developed such a tumor in the porta hepatis that provoked obstruction of the entire portal triad. Treatment consisted of systemic chemotherapy, percutaneous dilatation, and placement of Wallstent endoprostheses across both biliary and portal vein stenoses. The patient died 3 weeks later of pneumonia and sepsis. At necropsy, the tumor was completely necrosed and the prostheses in both the common bile duct and the portal vein were patent. 相似文献
8.
Ex vivo testing techniques were used to determine the ferromagnetic qualities of, presence of heating in, and artifacts produced by 13 different heart valve prostheses exposed to a 1.5-T (64-MHz) magnetic resonance (MR) system. None of the heart valve prostheses showed a measurable deflection in the 1.5-T static magnetic field. Only minimal artifacts were produced during MR imaging with a fast spoiled GRASS (gradient-recalled acquisition in the steady state) pulse sequence. The largest temperature changes measured during a “worst case” MR imaging sequence (estimated average specific absorption rate, 2.5 W/kg; estimated spatial peak specific absorption rate, 7.6 W/kg) were +0.2°C with the implant imaged “in air” and +0.3°C with the implant imaged in normal saline. Therefore, MR procedures performed with a 1.5-T (64-MHz) MR system may be performed safely in patients with any of the 13 different heart valve prostheses evaluated in this study. 相似文献
9.
The objective of the present study was to assess possible adaptive functional changes in the masticatory system after insertion of fixed prostheses supported by osseointegrated implants in the edentulous mandible. Registrations of mandibular movement characteristics and maximal biteforce were performed at insertion and after 1 week, 3 months and 1 year after connection. The duration of the opening and closing phase decreased and maximal biteforce increased significantly (p < or = 0.05-0.001) from connection of the prostheses to the annual check-up. However, the process of functional adaptation implied 2 identified stages. An immediate phase that occurred within the 1st week, probably due to altered impact from mechano-sensitive receptors and a later more time-dependent phase, based on learning and new cortical engrams. Accordingly, the process of adaptation will continue over a long period of time. 相似文献
10.
肝素联合VEGF预处理对人工血管内皮细胞生长及贴附率的影响 总被引:4,自引:1,他引:3
目的联合应用肝素及血管内皮细胞生长因子(VEGF)预处理以提高人工血管移植物内皮细胞(EC)生长及贴附率.方法联合应用肝素及血管内皮细胞生长因子预处理人工血管移植物,比较各组EC生长曲线和贴附率.结果肝素在体外与VEGF联合应用,可显著增加EC在人工血管内壁的贴附率,并对EC的增殖有一定的持续影响.结论肝素与VEGF联用,能促进EC在人工血管的增殖和贴附率. 相似文献