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11.
A small dose of isoprenaline or saline was administered intraperitoneally to rats 20 min before the administration of one of the amino acids l-dopa or l-tryptophan. Isoprenaline caused a marked increase in the brain concentration of the administered amino acid. Isoprenaline has previously been shown to cause a decrease in at least some of those plasma amino acids which compete with l-dopa and tryptophan for carrier-mediated transport into the brain. The effect of isoprenaline on the concentrations of dopa and tryptophan in the brain is suggested to be at least partly caused by a change in the relationship between endogeneous and administered amino acids. It is also possible that a direct effect of isoprenaline on the blood-brain barrier transport system contributes to the effect.The reported finding might be of clinical interest in view of the therapeutic importance of aromatic amino acids with a central site of action. 相似文献
12.
目的 :为了解农村儿童乙型肝炎 (乙肝 )疫苗接种率、首针及时接种率、全程及时接种率及乙肝病毒表面抗原(Hbs Ag)携带率和抗 - HBs阳转率 ,以便为乙肝疫苗纳入儿童计划免疫提供本底资料。方法 :2 0 0 2年 12月对安庆市农村≤ 3岁儿童进行了调查。结果 :调查的 930人中 ,乙肝疫苗全程接种率为 74 .30 % ,首针及时接种率为 36 .4 5 % ,全程及时接种率为 2 9.4 6 % ,首针及时接种率以 0岁组最高 (χ2 =2 3.2 3,P<0 .0 1) ;检出阳性者 15人 ,携带率为 1.6 1% ;调查合格接种乙肝疫苗儿童 6 31人 ,抗 - HBs阳性 4 93人 ,抗 - HBs阳转率为 78.13%。平原地区的首针及时率为 38.4 0 % ,高于山区 (χ2 =4 .5 6 ,P<0 .0 5 )。住院和在家分娩儿童的首针及时接种率分别为 4 8.74 %、14 .6 3% ,差异有非常显著的统计学意义 (χ2 =10 7.6 7,P<0 .0 1)。结论乙肝疫苗纳入计划免疫后 ,提高农村新生儿乙肝疫苗首针及时接种率和全程及时接种率是今后工作的重点 相似文献
13.
李琳 《中国生育健康杂志》2006,17(2):96-98
目的探讨染色体平衡易位与异常孕产的关系。方法采用外周血淋巴细胞培养和染色体G显带分析,对612对有异常孕产史的夫妇进行染色体检查。结果染色体平衡易位携带者检出率为3.3%(41/1 224),其中常染色体相互易位占58.5%(24/41),罗伯逊易位占39.0%(16/41),嵌合易位占2.4%(1/41)。9例为世界首报染色体异常核型,分别为:46,XY,t(11;12)(q13;q21);46,XX,t(3;20) (qll;q11);46,XX,t(15;16)(pll;q13);46,XY,t(2;14)(p16;q31);46,XY,t(4;10)(q25;p15);46,XX,t(3;8) (p26;q11);46,XY,t(6;16)(q15;p13);46,XX,t(18;22)(p10;q10);46,XY,t(18;22)(p10;q10)mat。总妊娠127次,早期妊娠流产率为86.6%(110/127)。结论染色体平衡易位携带者的异常孕产以早期妊娠自然流产为主要表现。 相似文献
14.
臭氧水消毒器对微生物杀灭效果的试验观察 总被引:1,自引:0,他引:1
目的:观察臭氧水消毒器产生臭氧水的杀菌效果。方法:采用悬液定量和载体定量杀菌试验进行检测。结果:该机产生含臭氧4.20mg/L的水溶液对大肠杆菌、金黄色葡萄球菌和白色念珠菌作用5min的杀灭率均为100%;当菌液中含有10%蛋白胨时,对大肠杆菌、金黄色葡萄球菌和白色念珠菌作用5min的杀灭率分别为55.67%、59.48%和37.44%。用消毒液流动浸泡载体定量杀菌试验,含臭氧4.20mg/L的水溶液作用30min对大肠杆菌、金黄色葡萄球菌和白色念珠菌的平均杀灭率分别为99.95%、99.99%和96.94%。结论:该臭氧水消毒器产生的臭氧水具有一定消毒效果。 相似文献
15.
《Vaccine》2021,39(45):6644-6652
Conjugation of carbohydrate antigens with a carrier protein is a clinically proven strategy to overcome the poor immunogenicity of bacterial polysaccharide. In addition to its primary role, which is to help generate a T cell-mediate long-lasting immune response directed against the carbohydrate antigen, the carrier protein in a glycoconjugate vaccine can also play an important role as a protective antigen. Among carrier proteins currently used in licensed conjugate vaccines, non-typeable Haemophilus influenzae protein D has been used as an antigenically active carrier protein. Our previous studies also indicate that some carrier proteins provide B cell epitopes, along with T cell helper epitopes.Herein we investigated the dual role of truncated rotavirus spike protein ΔVP8* as a carrier and a protective antigen. Capsular polysaccharide lipoarabinomannan (LAM), purified from Mycobacterium tuberculosis (M.tb), was chemically conjugated with ΔVP8*. Mouse immunization experiments showed that the resultant conjugates elicited strong and specific immune responses against the polysaccharide antigen, and the responses were comparable to those induced by Diphtheria toxoid (DT)-based conjugates. The conjugate vaccine induced enhanced antibody titers and functional antibodies against ΔVP8* when compared to immunization with the unconjugated ΔVP8*. Thus, these results indicate that ΔVP8* can be a relevant carrier protein for glycoconjugate vaccine and the glycoconjugates consisting of ΔVP8* with LAM are effective bivalent vaccine candidates against rotavirus and tuberculosis. 相似文献
16.
Increased implementation of proven prevention strategies is required to combat rising breast cancer incidence. We assessed use of risk reducing medication (RRMed) by Australian women at elevated breast cancer risk. Only 2.4% had ever used RRMed. Higher breast cancer risk was statistically significantly associated with use of RRMed (OR 1.82, 95%CI: 1.08–3.07, p = 0.02 for ≥30% lifetime risk compared with 16%–29% lifetime risk), but parity, education level and family history of breast cancer were not. Breast cancer prevention medications are underutilised. Efforts are needed to incorporate breast cancer risk assessment and risk management discussions into routine health assessments for women. 相似文献
17.
《Hemoglobin》2013,37(6):593-598
A new γ chain variant with an electrophoretic mobility at pH 8.1 between those of Hb S and Hb C was isolated and quantitated by DEAE-cellulose chromatography. It was readily identified with the use of various micro-chromatographic and sequencing procedures as α2Gγ2 94(FGl)Asp→Asn. The hemoglobin was named Hb F-Columbus-Ga. The quantity of this GY chain variant (as % total γ chain) was about 39% and the percentages of the normal Gγ and AγI chains were 37% and 24%, respectively. 相似文献
18.
Konstantin Musiychuk Natalie Stephenson Hong Bi Christine E. Farrance Goran Orozovic Maria Brodelius Peter Brodelius April Horsey Natalia Ugulava Abdel‐Moneim Shamloul Vadim Mett Shailaja Rabindran Stephen J. Streatfield Vidadi Yusibov 《Influenza and other respiratory viruses》2007,1(1):19-25
Historically, most vaccines have been based on killed or live‐attenuated infectious agents. Although very successful at immunizing populations against disease, both approaches raise safety concerns and often have limited production capacity. This has resulted in increased emphasis on the development of subunit vaccines. Several recombinant systems have been considered for subunit vaccine manufacture, including plants, which offer advantages both in cost and in scale of production. We have developed a plant expression system utilizing a ‘launch vector’, which combines the advantageous features of standard agrobacterial binary plasmids and plant viral vectors, to achieve high‐level target antigen expression in plants. As an additional feature, to aid in target expression, stability and purification, we have engineered a thermostable carrier molecule to which antigens are fused. We have applied this launch vector/carrier system to engineer and express target antigens from various pathogens, including, influenza A/Vietnam/04 (H5N1) virus. 相似文献
19.
20.
Summary We used the PCR to amplify three polymorphic regions of Factor IX gene on 35 Italian families: DdeI intron 1, MnlI exon f, and the polymorphism HhaI located 8 kb at the 3 end of FIX gene. We analyzed the MnlI and HhaI markers on DGGE and DdeI polymorphism on agarose gel. We reached an informativity of 78% and we found one mutation at codon 145 (exon f) during the screening for MnlI polymorphism. Furthermore, we performed 16 prenatal diagnoses on chorionic villus samples; five were female and 11 male. Four were uninformative three healthy and one affected male fetus were recognized by PCR techniques, two healthy and one affected fetus by Southern analysis. In three pregnant women examined for the first time during pregnancy, the PCR technique allowed us to perform a rapid diagnosis of noncarrier status, avoiding the fetal sampling procedures. 相似文献