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91.
Lena Thyrell Olle Sangfelt Boris Zhivotovsky Katja Pokrovskaja Yisong Wang Stefan Einhorn Dan Grandér 《Journal of interferon & cytokine research》2005,25(2):63-72
Interferons (IFNs) exert antitumor effects in several human malignancies, but their mechanism of action is unclear. There is a great variability in sensitivity to IFN treatment depending on both tumor type and the individual patient. The reason for this variable sensitivity is not known. The fact that several IFN-induced anticellular effects are exerted through modulation of proto-oncogenes and tumor suppressor genes may indicate that the malignant genotype may be decisive in the cell's sensitivity to IFN. To determine if a deregulated oncogene could alter the cellular response to IFN, a mouse lymphoma cell line (J3D) was stably transfected with the viral human papillomavirus-16 (HPV-16) E7 oncogene. The E7-transfected cells and their respective mock-transfected sister clones were treated with IFN-alpha and examined for possible IFN-induced anticellular effects. We found that the E7-transfected clones were greatly sensitized to IFN-alpha-induced apoptosis compared with their mock-transfected counterparts. Induction of apoptosis in the transfected cells correlated with the ability of IFN to activate parts of the proapoptotic machinery specifically in these cells, including activation of caspases and the proapoptotic protein Bak. In summary, our data suggest that transfection of malignant cells with the E7 oncogene can sensitize them to IFN-alpha-induced apoptosis. This demonstrates that an oncogenic event may alter the cellular sensitivity to IFN and might also have implications for treatment of HPV-related diseases with IFN. 相似文献
92.
随着现代信息社会的发展,图书馆的核心竞争力已关系到图书馆未来的生存和发展.文章分析了图书馆核心竞争力的构成及影响因素.提出了提升图书馆核心竞争力的策略. 相似文献
93.
利用旋转壁式生物反应器(Rotating wall vessel,RWV)体外培养脐带血干细胞,使其大量扩增,以满足临床应用对造血干/祖细胞的数量与质量要求。从脐带血分离得到的单个核细胞(Mononuclear cells,MNC)在T-flask中培养24h,之后接种到RWV反应器中,培养200h。每24h细胞计数,测量培养基的pH和渗透压变化;在144h和197h测CD34 细胞含量并做CFU-GM半固体培养。有核细胞(Nucleated cells,NC)与CD34 细胞在第197h,分别扩增了435.5±87.6倍和32.7±15.6倍,CFU-GM(Colony-forming unit-granulocyte/macrophage)细胞扩增了21.7±4.9倍。整个培养过程中,RWV反应器中的pH和渗透压都保持在造血细胞最佳的扩增条件内,pH基本保持在7.2~7.4之间,渗透压基本保持在290~310mmol/kg之间。由于旋转壁式生物反应器(RWV)结构上的特殊性,可以保证细胞在悬浮流动的状态下生长,很好地模拟了脐带中的造血微环境,使脐带血造血干细胞在该反应器中短期内得到大量扩增。 相似文献
94.
95.
T Sakuragi S Shono H Isino T Oyama K Dan 《Masui. The Japanese journal of anesthesiology》1990,39(12):1637-1645
The "afterdrop" in body temperature (TEMP) following adequate rewarming from hypothermic cardiopulmonary bypass (CPB) is frequently observed. This temperature drop sometimes accompanied by shivering results in increased myocardial oxygen demand. We investigated the relations between the afterdrop and use of vasodilators after CPB. For vasodilator therapy, PGE1 at the rate of 0.025-0.088 microgram.kg-1.min-1 (Prostaglandin Low Doses, PLD; n = 8), 0.107-0.136 microgram.kg-1.min-1 (Prostaglandin High Doses, PHD; n = 7), or phentolamine at 4.1-5.9 micrograms.kg-1.min-1 (PHENT; n = 8) were intravenously infused in 23 adult patients after CPB. During three hour period after CPB, esophageal, rectal, and forehead TEMP are lower in PHENT than in PGE1 groups. There were significant differences between PHD and PHENT group. Finger tip TEMP was lower in PGE1 groups than in PHENT group. There were significant differences between PHD and PHENT group. There were no differences in systemic arterial pressure, cardiac index (CI) and systemic vascular resistance (SVR) at any point between PHD and PHENT groups. It is concluded that PHENT increases the peripheral skin blood flow and TEMP but decreases the visceral TEMP possibly due to vasodilatation of the skin vessels, while PGE1 decreases skin blood flow and TEMP but increases the visceral TEMP, although SVR clearly decreases at the same rate in the two groups. 相似文献
96.
John J. Ryan Dan Levesque Luz G. Panopio Wing F. Sun Yoshito Masuda Hiroaki Kuroki 《Archives of environmental contamination and toxicology》1993,24(4):504-512
The pharmacokinetics of polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) in humans was studied by monitoring the blood concentrations of individuals who ingested a contaminated rice oil in Japan (yusho) in 1968 and in Taiwan (yu-cheng) in 1979. Sixteen yusho patients were followed from 1982 to 1990 and three yu-cheng individuals from 1980 to 1989. From the three yucheng patients, blood lipid values for the two persistent toxic congeners, 2,3,4,7,8-pentachlorodibenzofuran (PnCDF) and 1,2,3,4,7,8-hexachlorodibenzofuran (HxCDF), varied from 50 g/kg at first sampling to about 1 g/kg at last sampling corresponding to half-lives for elimination (t1/2) of 2-21/2 years. The blood lipid values for the same PCDF congeners in yusho patients varied from 5 g/kg down to 0.1 g/kg. The calculated t1/2 were more variable with median values closer to 10 years. Planar PCBs #126 and #169 were present at lower concentrations than the PCDFs. For seven of the other PCB congeners, half-lives for elimination in the yu-cheng individuals varied from 1.2 up to 4.6 yr depending on the degree of chlorination. For the yusho patients, the elimination for the PCBs was longer. These results show that clearance of the toxic PCDFs and PCBs in humans is non-linear with faster elimination at higher exposure followed by slower decreases as background levels are approached. Such a clearance pattern can best be explained by a two compartment liver and fat pharmacokinetic model. 相似文献
97.
大网膜移植抑制大鼠脊髓损伤后神经细胞凋亡的实验研究 总被引:2,自引:0,他引:2
目的 探讨脊髓损伤(SCI)后神经细胞凋亡的发生机制和伤后立即行大网膜脊髓移植是否对神经细胞凋亡具有抑制作用。方法 制作程控电磁吸铁棒下落打击脊髓损伤模型,运用末端脱氧核苷酸转移酶介导生物素标记(TUNEL)方法检测细胞凋亡,分别观察SCI后1d、2d、7d组与伤后即刻施行大网膜移植组(存活7d)的细胞凋亡。结果 脊髓灰质区在伤后1d、、2d时TUNEL阳性细胞数最多;脊髓白质区在伤后1d时TUNEL阳性细胞数最多,伤后7d出现第2次高峰;伤后大网膜脊髓移植的TUNEL阳性细胞数较7d明显降低。结论 SCI后白质区和灰质区存在不同演变过程的神经细胞凋亡,SCI后即刻大网膜脊髓移植对细胞凋亡有抑制作用。 相似文献
98.
谢仿征 《中国自然医学杂志》2000,2(2):88-89
目的 分析运用第二掌骨侧生物全息疗法治疗Ⅱ型糖尿病21例疗效。方法 取第二掌骨侧相关穴位肺、胃(胰、脾)穴、肾穴,分左右两组交替使用。每日针刺或按摩两次,每次10min。如针刺,得气后留针15min。15次为一疗程。一般经两个疗程治疗后复查血糖、尿糖与治疗前对照。结果 显效6例占28.6%;有效13例占61.9%;无效2例占9.5%。总有效人数19例;总有效率90.5%。结论 治病结果表明,第二掌骨侧生物全息疗法,见效快、效率高,是一套新的高效治疗技术,宜广泛推广。 相似文献
99.
【目的】研制一个计算机辅助的心血管信号检测和处理系统。【方法】本系统的硬件设计采用奔腾 Ⅱ / 2 33多媒体微机系统 ,多路模 /数转换器和心电电极、心音传感器、脉搏波传感器及由运算放大器等构成相关的放大器及滤波器。本系统采用可视化编程环境构建系统结构和功能模块设计的方法 ,基于多媒体技术和小波变换原理 ,在 32位Windows平台下 ,利用可视化编程语言VisualC 6 0和多媒体著作工具Authorware等进行系统的软件设计。【结果】本系统能完成心电、心音、脉搏波信号检测和处理 ,并将结果以图、文、声并茂的形式显示、打印或播放 ,还具有病案管理和心音听诊多媒体计算机辅助教学功能。【结论】它是一个新型的多功能心血管信号检测和处理系统。 相似文献
100.
对比大理地区健康汉族人与白族人血清总三碘甲状腺原氨酸(TT3)、总甲状腺素(TT4)含量,建立本地区健康人TT3、TT4正常参考值。方法:对1007例健康人(汉族691例,白族316例)进行血清TT3、TT4、RIA检测。结果:健康汉族人与白族人血清TT3、TT4测定值相近,经统计学处理无显著性差异(P>005);60~75岁年龄组的健康老年人血清TT3、TT4含量比其他年龄组明显降低(P<001)。结论:经检测得出的各年龄TT3、TT4水平,不论白族或汉族,男性或女性,均可作为正常参考值;60岁以上健康老人TT3、TT4含量低于其他年龄是老年人正常的生理变化。 相似文献