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181.
Izabela Zglobicka Magdalena Joka-Yildiz Rafal Molak Michal Kawalec Adrian Dubicki Jakub Wroblewski Kamil Dydek Anna Boczkowska Krzysztof J. Kurzydlowski 《Materials》2022,15(18)
The poly(lactic acid) (PLA) biodegradable polymer, as well as natural, siliceous reinforcement in the form of diatomaceous earth, fit perfectly into the circular economy trend. In this study, various kinds of commercial PLA have been reinforced with diatomaceous earth (DE) to prepare biodegradable composites via the extrusion process. The structure of the manufactured composites as well as adhesion between the matrix and the filler were investigated using scanning electron microscopy (SEM). Differential scanning calorimetry (DSC) analyses were carried out to determine crystallinity of PLA matrix as function of DE additions. Additionally, the effect of the ceramic-based reinforcement on the mechanical properties (Young’s modulus, elongation to failure, ultimate tensile strength) of PLA has been investigated. The results are discussed in terms of possible applications of PLA + DE composites. 相似文献
182.
混合稀土常乐在孕鼠和胎鼠肝中的蓄积及对肝脏钙含量的影响 总被引:8,自引:2,他引:6
目的 :观察混合稀土常乐在孕鼠和胎鼠肝中的蓄积情况以及对钙 ( Ca2 + )含量的影响。方法 :采用电感耦合等离子体质谱法和电感耦合等离子体原子发射光谱法分别检测孕鼠和胎鼠肝中镧 ( La3 + )、铈 ( Ce3 + )、镨 ( Pr3 + )、钕 ( Nd3 + )和钙含量变化。结果 :孕鼠 2 0 mg· kg-1常乐组肝中La3 + 、Ce3 + 和 Nd3 + 含量高于对照组 ( P <0 .0 5 ) ;孕鼠肝脏 Ca2 + 含量各实验组高于对照组( P<0 .0 5 )。结论 :孕鼠 2 0 mg· kg-1常乐组稀土元素在孕鼠肝中有蓄积 ,各实验组孕鼠肝脏钙含量均有变化 ;胎鼠肝脏稀土含量和钙含量无变化 相似文献
183.
对186例稀土作业工人的血清IgG,IgA,IgM和补体C3进行测定,并与120例非稀土作业者进行了对比观察,还测定了环境粉尘浓度,总放射性和γ照射量率。稀土作业工人的IgG,IgA,和C3均有明显变化,提示稀土作业环境对工人的体液免疫有一定影响。但依据总放射量中位数,作业环境开放性放射性场所最低类,个体的γ照射率远低于标准,故可认为一定影响,但依据总放射量中位数,作业环境为开放性放射性场所最低类 相似文献
184.
V.L. Cherginets T.G. Deineka O.V. Demirskaya T.P. Rebrova 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2002,531(2):171-178
The sequential additions method (SAM) was used to determine solubility and disassociation characteristics of metal oxides MeO (CaO, PbO, ZnO, CdO) and carbonates (CaCO3, SrCO3, BaCO3) in molten KCl–NaCl eutectic at 700 °C. A membrane oxide-reversible electrode Pt(O2)/YSZ) was used to detect oxide ion concentrations. The oxides (MeO) were found to be weak bases in unsaturated solutions, their dissociation constants (pK) were found to be 3.27±0.2 (CaO), 3.50±0.1 (PbO), 6.1±0.2 (ZnO) 5.3±0.2 (CdO). All the emf?(?log mMeO) plots in the vicinity of the saturation point include bends to the concentration axis. These were explained by the partial dissolution of MeO powders resulting in a decrease of their particle sizes and a corresponding rise of the molar surface areas (MSA). Calculations performed give surface energies of MeOsolid/KCl–NaCl systems of the order of 30–50 J m?2. This allowed us to estimate MSAs of the MeO particles formed in MeO solubility determinations in molten KCl–NaCl by isothermal saturation and potentiometric titration methods. The solubilities of the alkaline earth carbonates were determined in a CO2 atmosphere. Under these conditions solubility products of the carbonates were achieved before oxide precipitation. The alkaline earth carbonates were found to be appreciably soluble in the KCl–NaCl eutectic at 700 °C. Their solubility products determined by SAM were equal to pPBrCO3=0.36±0.3, pPSrCO3=2.04±0.2, pPCaCO3=2.04±0.2 (in a CO2 atmosphere). Under these conditions the particle size effect was imperceptible. 相似文献
185.
186.
为解决外科手术中的引流问题 ,研制了一种涤纶网加强型医用硅橡胶引流条。该产品是用医用加成型硅橡胶与涤纶网复合 ,通过模压方式制作的波纹状引流条。经临床应用表明引流效果好 ,使用方便 ,能促进伤口愈合 相似文献
187.
Clinical, brain electric earth map, endothelin and transcranial ultrasonic Doppler findings after hyperbaric oxygen treatment for severe brain injury 总被引:10,自引:1,他引:9
Objective To analyze the effect and mechanism of hyperbaric oxygen (HBO) treatment for severe brain injury (SBI). Methods Fifty-five patients were divided into a treatment group of 35 patients and a control group of 20 patients. We observed the alterations of clinical, brain electric earth map (BEAM), endothelin (ET) and transcranial ultrasonic Doppler (TCD) findings before and after HBO treatment as well as outcome. Results In the treatment group, Glasgow coma scale, BEAM and outcome improved after HBO treatment; compared with that of the control group, it showed a significant difference. After one course of treatment, treatment group ET was reduced from 91.24±12.18?ng/L to 68.88±14.37?ng/L (P<0.01); in control group, ET was reduced from 90.78±15.71?ng/L to 83.12±12.22?ng/L, with a statistically significant difference (P<0.05). TCD records of MCA mean velocity (Vm) was reduced from 64.2±4.8?cm/s to 51.6±4.2?cm/s (P<0.01), and a decrease in MCA systolic velocity (Vs) and pulse index (PI) values was statistically significant (P<0.01). Conclusion HBO treatment can improve the clinical, BEAM and outcome of severely brain injured patients, by decreasing acute stage ET and improving the blood velocity of MCA and decreasing cerebral vascular resistance. HBO treatment can reduce cerebral vascular spasms, cerebral ischemia and hypoxia. One of the important mechanisms of HBO treatment for severe brain injury is the lowering of intracranial pressure. 相似文献
188.
目的建立全自动石墨消解-电感耦合等离子体质谱(ICP-MS)一次性测定16种稀土元素的定量方法,实现人发样品的快速测定。方法以10 ml硝酸和2 ml氢氟酸混合作为消解液,全自动石墨方式进行消解前处理,以103Rh、185Re作为内标消除非质谱干扰,氨气反应模式消除质谱干扰,采用电感耦合等离子体质谱进行快速定量测定。结果在优化的实验条件下,16种待测元素均在0.1μg/L^10μg/L浓度线性良好(r值为0.999 67~0.999 98),检出限为0.12μg/kg^1.90μg/kg,定量限为0.41μg/kg^6.34μg/kg,加标回收率为81.6%~110.5%。结论该方法简单快速、准确可靠,可实现全自动化前处理,适用于人发中16种稀土元素的同时测定,为生物样品中稀土元素含量的调查和诊断提供了新思路。 相似文献
189.
目的 观察培土生金法治疗气虚型小儿反复呼吸道感染的临床疗效。方法 选取70例气虚型反复呼吸道感染患儿,随机分为观察组和对照组各35例。其中对照组患儿予常规西医药物治疗,观察组患儿加服培土生金中药,7 d为1个疗程,连服4个疗程并随访1年,观察并比较两组患儿治疗前后1年内呼吸道感染次数和每次症状持续时间,评价临床疗效。结果 观察组临床疗效明显优于对照组,差异有统计学意义(P<0.05)。两组患儿1年内呼吸道感染次数和每次症状持续时间均较治疗前明显下降(P<0.05),观察组下降程度明显大于对照组(P<0.05)。结论 培土生金法可防治小儿气虚型反复呼吸道感染。 相似文献
190.
"呼多吸少"是临床常见现象,最常见于以慢性阻塞性肺疾病为代表的慢性气道疾病。以文献与理论论述为基础,结合临床解读"呼多吸少",认为"呼多吸少"从现代医学角度可以解释为由于气道炎症及远端气道破坏、重塑,气道及肺泡弹性回缩力减退造成的呼气时相延长;在中医方面,"呼多吸少"则与肺失宣肃、肺脾气虚、肺肾亏虚密切相关,不能单纯理解为"肾不纳气",治疗方面提出"辛开苦降、补脾益肺、补肺纳肾"为相应病证的治疗原则。 相似文献