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61.
Takakura Yoshinobu Fujita Takuya Hashida Mitsuru Sezaki Hitoshi 《Pharmaceutical research》1990,7(4):339-346
As part of the strategy for the design of macromolecular carriers for drug targeting, the disposition characteristics of macromolecules were studied in mice bearing tumors that served as target tissues. Eight kinds of macromolecules including four polysaccharides and four proteins with different molecular weights and electric charges were used; tissue distribution and tumor localization after intravenous injection were studied. Pharmacokinetic analysis revealed that the tissue radioactivity uptake rate index calculated in terms of clearance was different among the tested compounds; especially, the urinary radioactivity excretion clearances and the total hepatic radioactivity uptake clearances varied widely. Compounds with low molecular weights (approximately 10 kD) or positive charges showed lower tumor radioactivity accumulation; radioactivity was rapidly eliminated from the plasma via rapid urinary excretion or extensive hepatic uptake, respectively. On the other hand, large and negatively charged compounds, carboxymethyl dextran, bovine serum albumin, and mouse immunoglobulin G, showed higher radioactivity accumulation in the tumor (calculated total amounts were 15.6, 10.8, and 20.8% of the dose, respectively) and prolonged retention in the circulation. These results demonstrated that the total systemic exposure rather than the uptake rate index was correlated with total tumor uptake. Molecular weight and electric charge of the macromolecules significantly affected their disposition characteristics and, consequently, determined radioactivity accumulation in the tumor. It was concluded that a drug–carrier complex designed for systemic tumor targeting should be polyanionic in nature and larger than 70,000 in molecular weight. 相似文献
62.
目的:了解射击运动员高脂血症的发生情况和可能的引发因素,为预防高脂血症提供依据。方法:对从事专业训练半年以上,无急慢性疾病的53名省级优秀射击运动员进行膳食调查和血清脂质水平检测。结果:运动员的高脂血症检出率为28.3%,全部为高甘油三脂血症;膳食中 运动员除了摄入维生素B1、B2不足和维生素A缺乏外,其他各类营养素基本能满足机体需要,属基本合理膳食。结论:以抗阻训练和静力运动为运动特征的射击运动,可能会对机体血脂代谢产生不利的影响。 相似文献
63.
郑州市1996~2005年梅毒流行病学分析 总被引:7,自引:0,他引:7
目的寻求郑州市梅毒流行规律和特点,为制订防治政策提供依据。方法对1996~2005年郑州市梅毒病例资料进行分析。结果1996~2005年梅毒的发病率呈上升趋势。以早期梅毒为主,一期梅毒发病数高于二期梅毒;梅毒感染者主要在20~44岁年龄段,占60.05%;工人、农民、待业、商业服务、干部分别占20.44%,18.15%,11.52%,8.54%,6.25%。结论应加强梅毒防治工作力度,规范梅毒诊治,全面实施健康教育、行为干预等综合防治措施。 相似文献
64.
65.
Summary We present a simple method for the isolation of DNA from agarose gels that is economic, fast, and independent of electrical equipment. DNA fragments of up to 6 kb can be easily extracted within 5 min using a disposable plastic syringe and filter paper. Total extraction of DNA fragments between 10 and 20 kb in size is achieved by concentrating the DNA flushed from the gel in a DNA-binding column. 相似文献
66.
rhTPO在大肠杆菌中的表达、纯化及生物活性分析 总被引:1,自引:0,他引:1
目的:探讨人促血小板生成素(human thromlbopoietin,hTPO)在大肠杆菌中表达、分离纯化及生物学活性初步鉴定。方法:利用RT-PCR法从人胎肝细胞中扩增目的基因片段,将其定向插入pQE30表达质粒T5启动子下游的多克隆区,转化大肠杆菌M15,得到pQE30-TPO的工程菌,诱导目的蛋白表达、纯化。将表达产物给血小板减少模型小鼠尾静脉注射,观察注射后不同时间血小板量的改变。结果:经异丙基硫代-β-D-半乳糖苷(isopropylthio-β-D-galactoside IPTG)诱导培养,该工程菌可以产生单一特异性的高表达蛋白条带。将纯化后的表达蛋白注射小鼠,结果显示对实验性小鼠血小板减少症具有一定的治疗作用。结论:在大肠杆菌中成功地高效表达了重组hTPO,该产物具有促血小板生成的活性。 相似文献
67.
刘德荣 《福建中医学院学报》2003,13(1):42-44
北宋名医吴本的精湛医术和高尚医德在漳州、泉州和台南民众中久为传颂,流感在慈济宫的“济世仙方药鉴”是现存有关吴本的宝贵医药资料,该药签体现了中医的选方特点和用药特点,今天仍有整理研究的价值。 相似文献
68.
目的 分析富含三酰甘油脂蛋白(TRLs)分子组成及其代谢特征.方法应用脂蛋白电泳技术,对30例飞行员空腹和脂肪负荷餐后血浆做脂蛋白分析,以扫描图面积表示各亚组分构成,观察脂蛋白亚组分变化特点.结果 30例飞行员TRLs清除延迟发生率46.67%.TRLs分子脂蛋白亚组分由极低密度脂蛋白(VLDL)、中密度脂蛋白(IDL)、低密度脂蛋白(LDL)、乳糜微粒(CM)和脂蛋白a[LP(a)]组成.TRLs清除延迟典型扫描图特征为LDL左侧区面积增高,呈双峰或多峰.LDL、VLDL区面积增高,伴有高密度脂蛋白(HDL)面积降低.结论 高三酰甘油血症致动脉粥样硬化作用是在代谢水平异常所致的TRLs清除延迟,TRLs清除延迟是核心环节. 相似文献
69.
目的 探讨肝脏移植后的免疫损伤与几种主要分子伴侣(热休克蛋白)表达状况之间的内在规律。方法 34份移植后肝脏穿刺标本和10份正常肝脏标本,分为A(无排斥反应)组、B(轻/中度急性排斥反应)组、C(重度急性排斥反应)组、D(慢性排斥反应/肝纤维化)组、E(对照)组。进行HSP60、HSP70、HSP90、HO—1等四种分子伴侣免疫组织化学分析和图像分析。结果 B和C组各指标间无统计学差异,A、D、E与B、C组间有统计学差异。HSP60在移植肝脏中表达降低,排斥反应发生时高;HSP70和HSP90在移植肝脏中升高。HO—1肝脏移植后升高。结论 不同种类的热休克蛋白依据自身表达的特点对移植后的免疫损伤作出反应,体现了细胞的自我保护机制。 相似文献
70.
Jaques AM Halliday JL Francis I Bonacquisto L Forbes R Cronin A Sheffield LJ 《BJOG : an international journal of obstetrics and gynaecology》2007,114(7):812-818
Objective The objective of this study was to follow up and evaluate the statewide first-trimester combined screening programme for Down syndrome and trisomy 18 at Genetic Health Services Victoria, Australia.
Design Retrospective population cohort.
Setting Maternal Serum Screening Laboratory records.
Sample All women screened between February 2000 and June 2002 (16 153 pregnancies).
Methods Screening results were matched to Victorian perinatal and birth defect data via record linkage, with an ascertainment of 96.8% of pregnancy outcomes. Manual follow up with health professionals increased ascertainment to more than 99%.
Main outcome measures Fetal Down syndrome or trisomy 18, and combined screen results, to calculate test characteristics.
Results Using a risk threshold of 1 in 300 at time of ultrasound, the sensitivities for standard first-trimester combined screening and augmented 13-week combined screening for Down syndrome were 87.3 and 90.5% and the false-positive rates (FPR) were 4.1 and 3.9%, respectively. The sensitivity for trisomy 18 was 66.7% (10/15, 95% CI 42.8–90.5%) with a 0.4% FPR and 15.2% positive predictive value (1 in 250 risk threshold).
Conclusions The combined use of record linkage and manual follow-up techniques was effective in ascertaining more than 99% of pregnancy outcomes for calculations of accurate test characteristics of the combined screen. The sensitivity for Down syndrome at Genetic Health is comparable to similar populations. However, the sensitivity for trisomy 18 is lower than that elsewhere, which may reflect the overall low birth prevalence of trisomy 18 and associated small numbers in this particular cohort. 相似文献
Design Retrospective population cohort.
Setting Maternal Serum Screening Laboratory records.
Sample All women screened between February 2000 and June 2002 (16 153 pregnancies).
Methods Screening results were matched to Victorian perinatal and birth defect data via record linkage, with an ascertainment of 96.8% of pregnancy outcomes. Manual follow up with health professionals increased ascertainment to more than 99%.
Main outcome measures Fetal Down syndrome or trisomy 18, and combined screen results, to calculate test characteristics.
Results Using a risk threshold of 1 in 300 at time of ultrasound, the sensitivities for standard first-trimester combined screening and augmented 13-week combined screening for Down syndrome were 87.3 and 90.5% and the false-positive rates (FPR) were 4.1 and 3.9%, respectively. The sensitivity for trisomy 18 was 66.7% (10/15, 95% CI 42.8–90.5%) with a 0.4% FPR and 15.2% positive predictive value (1 in 250 risk threshold).
Conclusions The combined use of record linkage and manual follow-up techniques was effective in ascertaining more than 99% of pregnancy outcomes for calculations of accurate test characteristics of the combined screen. The sensitivity for Down syndrome at Genetic Health is comparable to similar populations. However, the sensitivity for trisomy 18 is lower than that elsewhere, which may reflect the overall low birth prevalence of trisomy 18 and associated small numbers in this particular cohort. 相似文献