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81.
The present study aimed to assess the radiological parameters from gamma rays due to the uncontrolled disposal of porcelain waste to the environment. Qualitative and quantitative identification of radionuclides in the investigated samples was carried out by means of a high-purity germanium (HPGe) detector. The average activity concentrations of the local porcelain samples were measured as 208.28?Bq/kg for 226Ra, 125.73?Bq/kg for 238U, 84.94?Bq/kg for 232Th and 1033.61?Bq/kg for 40K, respectively. The imported samples had an average activity of 240.57?Bq/kg for 226Ra, 135.56?Bq/kg for 238U, 115.74?Bq/kg for 232Th and 1312.49?Bq/kg for 40K, respectively. Radiological parameters and the radium equivalent Raeq for the investigated samples were calculated. The external and internal hazard indices, representative level index (Iγ), alpha index (Iα), and the exemption level (Ix), were estimated to be higher than the recommended value (unity), while the average activity concentrations for the studied samples were higher than recommended levels. In conclusion, we are concerned that disposal of porcelain in the environment might be a significant hazard. 相似文献
82.
《Expert review of anticancer therapy》2013,13(10):1433-1447
Microtubules and their component protein, tubulin, constitute a popular target for the treatment of cancer. Many drugs that are presently used in clinics or in clinical trials and drugs that show promise as anticancer drugs bind to tubulin and microtubules. There are three conventional binding sites on β-tubulin where many of these drugs bind. The binding properties, conformational changes upon binding, association constants and thermodynamic parameters for the drug–tubulin interaction on these three sites are discussed. The antiproliferative activities of these drugs and the possible correlation with the binding properties are also described. 相似文献
83.
Chi-Ting Horng Jon-Kway Huang Hui-Yun Wang Chi-Chang Huang Fu-An Chen 《Nutrients》2014,6(11):5327-5337
Polygonatum alte-lobatum Hayata, a rhizomatous perennial herb, belongs to the Liliaceae family and is endemic to Taiwan. We investigated the antioxidant and anti-fatigue activities of P. alte-lobatum in exercised rats. Levels of polyphenols, flavonoids and polysaccharides and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical scavenging activity were measured in extracts of P. alte-lobatum (EPA). Sprague-Dawley rats were randomly divided into four groups for 8-week treatment with vehicle (control) and low-, medium-, and high-dose EPA (LEPA, MEPA, HEPA; 0, 75, 150, and 375 mg/kg/day, respectively). Exercise performance was evaluated by exhaustive treadmill exercise time and by changes in body composition and biochemical variables at the end of the experiment. EPA contained polyphenols, flavonoids and polysaccharides, with polysaccharide content at least 26 times greater than that of polyphenols and flavonoids. Trend analysis revealed that EPA dose-dependently scavenged DPPH free radicals. EPA treatment dose-dependently increased endurance running time to exhaustion and superoxide dismutase activity and total antioxidant ability of blood. EPA dose-dependently decreased serum urea nitrogen and malondialdehyde levels after exercise. Hepatic glycogen content, an important energy source for exercise, was significantly increased with EPA treatment. EPA could be a potential agent with an anti-fatigue pharmacological function. 相似文献
84.
Eli D. Scher Inaya Ahmed Ning J. Yue Salma K. Jabbour 《Journal of gastrointestinal oncology.》2014,5(3):198-211
Historically treated with surgery, current practice recommends anal carcinoma to be treated with a combination of chemotherapy and radiation. This review will examine the anatomy, modes of disease spread and recurrence, and evaluate the existing evidence for treatment options for these tumors. An in-depth examination of specific radiation therapy (RT) techniques—such as conventional 3D-conformal RT and intensity-modulated RT—will be discussed along with modern dose constraints. RT field arrangement, patient setup, and recommended gross and clinical target volume (CTV) contours will be considered. Areas in need of further investigation, such as the role in treatment for positron emission tomography (PET) will be explored. 相似文献
85.
86.
《International journal of audiology》2013,52(5):384-394
The behaviour of 95 clinically normal 6-month-old babies previously studied as neonates and as 6-week-old infants was video-recorded while they were presented with sound stimuli. The stimulus series varied in sound pressure level (SPL) (30 and 60 dB), band width (BW) and rise time (RT), and included two voice signals and a no-sound (control) trial. Video-records were made both for the whole body aspect and for a 31/2 'close-up' of the head. Later, the video-records were shown to 6 observers who were allowed to see the babies for 13 s at each trial. The first 5 s was a pre-stimulus observation period, and the second 8 s usually contained a sound stimulus. Between the trials, the observers were given 20 s in which to record pre-stimulus activity, confidence in response, and movement details. Data for movement details are not reported here. Different segments of the baby's body were observed on different occasions as detailed in our previous reportsThe confidence ratings for response to tonal stimuli were analysed using aspects of signal detection theory for differences amongst various body segments (n.s.), SPL (p < 0.001), BW (p < 0.05), and RT (p < 0.01). A 60-dB broad-spectrum noise band (BSN) and the 2 voices were by far the most effective stimuli. They elicited detectabilities which differed between segments. The response to different sound stimuli was affected by the baby's pre-stimulus activity state. The results are discussed in relation to our previous studies 相似文献
87.
Ivona Markelić Iva Hlapčić Dunja Rogić Ivana Rako Miroslav Samaržija Sanja Popović-Grle Lada Rumora Andrea Vukić Dugac 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2021,31(1):153-161
Background and aimsLimited number of studies investigated lipid profile in chronic obstructive pulmonary disease (COPD) with inconsistent results. This study aimed to investigate lipid parameters in sera of patients with stable COPD and their associations with disease severity, smoking, comorbidities and therapy.Methods and resultsThe study included 137 COPD patients and 95 controls. Triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) were assessed. Non-HDL-C (NHC), atherogenic coefficient (AC), TG/HDL-C, atherogenic index of plasma (AIP), Castelli's risk index I and II (CRI-I, CRI-II), and monocyte to HDL ratio (MHR) were calculated.HDL-C and MHR were increased, while other lipid parameters and indices were decreased in COPD patients compared to healthy individuals. Smoking did not influence lipid parameters. However, lipid profile was altered only in more severe disease stages. AC, CRI-I and CRI-II showed positive association with lung function parameters in COPD patients, and negative with COPD multicomponent indices (ADO, BODCAT, BODEx, CODEx and DOSE). Combined model that included CRI-II, C-reactive protein, fibrinogen and white blood cells showed great diagnostic performances, and correctly classified 72% of study participants with an AUC of 0.800 (0.742–0.849), P < 0.001. Bronchodilator monotherapy and statins have opposite impact on TC, LDL-C and NHC, while TG, TG/HDL-C and AIP were increased in COPD patients with cardiovascular diseases.ConclusionLipid disbalance is present in COPD, and it seems to occur later as the disease progresses. Further studies are needed to illuminate the underlying mechanism of dyslipidaemia. 相似文献
88.
89.
目的 对职业性三硝基甲苯(TNT)白内障患者治疗前后眼部血流动力学改变进行分析,了解其治疗效果.方法 对广西壮族自治区职业病防治研究院2010-2012年期间收治45例职业性TNT白内障患者的临床资料进行回顾性的分析,采用黄芪注射液联合还原型谷胱甘肽滴眼液对45例患者实施治疗,B超检查眼动脉、视网膜中央动脉血流改变情况,比较、分析治疗前、后的眼部血流动力学情况.结果 经过一段的时间的治疗以后,45例职业性TNT白内障患者眼部的眼动脉收缩期的平均血流速度、眼动脉舒张期的平均血流速度、视网膜中央动脉收缩期的平均血流速度、视网膜中央动脉舒张期的平均血流速度与治疗前比较都有提高,其中眼动脉和视网膜中央动脉收缩期血流速度与治疗前比较差异具有统计学意义(P<0.05).结论 职业性TNT白内障患者,其眼部周围的血液循环存在供血不足的问题,采用黄芪注射液联合还原型谷胱甘肽滴眼液的治疗方法来扩张眼部血管、增加眼部血流量,对于改善TNT白内障患者眼部的血流动力、促进其视力恢复具有积极意义. 相似文献
90.
目的:研制开发基于ADuC848的便携式多参数检测仪,并对整个系统进行详细的分析。方法:该测试仪采用ADuC848单片机作为处理芯片,通过240×128点阵图形LCD显示屏进行显示和功能设置。结果:该测试仪可以对压力、真空度、温度、湿度、气体流量等多种参数进行检测,满足了医疗设备测试与计量的实际需要。结论:多参数测试仪测量精度高、操作简便,完全可替代国外同类仪器。 相似文献