全文获取类型
收费全文 | 3419篇 |
免费 | 287篇 |
国内免费 | 46篇 |
专业分类
耳鼻咽喉 | 26篇 |
儿科学 | 163篇 |
妇产科学 | 41篇 |
基础医学 | 422篇 |
口腔科学 | 44篇 |
临床医学 | 384篇 |
内科学 | 744篇 |
皮肤病学 | 53篇 |
神经病学 | 173篇 |
特种医学 | 430篇 |
外科学 | 415篇 |
综合类 | 220篇 |
预防医学 | 264篇 |
眼科学 | 43篇 |
药学 | 179篇 |
2篇 | |
中国医学 | 33篇 |
肿瘤学 | 116篇 |
出版年
2022年 | 33篇 |
2021年 | 48篇 |
2020年 | 46篇 |
2018年 | 36篇 |
2017年 | 40篇 |
2016年 | 31篇 |
2015年 | 52篇 |
2014年 | 84篇 |
2013年 | 108篇 |
2012年 | 141篇 |
2011年 | 133篇 |
2010年 | 125篇 |
2009年 | 131篇 |
2008年 | 129篇 |
2007年 | 144篇 |
2006年 | 148篇 |
2005年 | 110篇 |
2004年 | 104篇 |
2003年 | 104篇 |
2002年 | 105篇 |
2001年 | 92篇 |
2000年 | 67篇 |
1999年 | 72篇 |
1998年 | 112篇 |
1997年 | 91篇 |
1996年 | 79篇 |
1995年 | 78篇 |
1994年 | 49篇 |
1993年 | 59篇 |
1992年 | 65篇 |
1991年 | 50篇 |
1990年 | 46篇 |
1989年 | 68篇 |
1988年 | 71篇 |
1987年 | 74篇 |
1986年 | 53篇 |
1985年 | 68篇 |
1984年 | 32篇 |
1983年 | 39篇 |
1982年 | 34篇 |
1981年 | 27篇 |
1980年 | 27篇 |
1979年 | 29篇 |
1978年 | 29篇 |
1977年 | 31篇 |
1976年 | 28篇 |
1958年 | 29篇 |
1956年 | 30篇 |
1955年 | 42篇 |
1954年 | 36篇 |
排序方式: 共有3752条查询结果,搜索用时 15 毫秒
31.
Bicarbonate versus citrate in oral rehydration therapy in infants with watery diarrhea: a controlled clinical trial 总被引:1,自引:0,他引:1
E Salazar-Lindo R B Sack E Chea-Woo R Leon-Barua B A Kay A Yi A D Robertson 《The Journal of pediatrics》1986,108(1):55-60
In a double-blind, randomized trial, we compared the efficacy of bicarbonate-containing oral rehydration solution vs citrate-containing solution in the treatment of infantile diarrheal dehydration and acidosis. Ninety-seven infants 3 to 24 months of age were entered in the study; 49 received bicarbonate-containing solution and 48 citrate-containing solution. The two groups were similar in all respects at the beginning of the study. Oral rehydration was successful (i.e., no intravenously administered fluids were required) in 85% of study patients; the success rate was similar in both treatment groups. Serum total CO2 concentration increased in a similar fashion in both groups, reaching near normal values at 48 hours after admission. We conclude that sodium citrate can be substituted for sodium bicarbonate in the formulation of the orally administered rehydration solution recommended by the World Health Organization for treatment of diarrheal dehydration in infants. 相似文献
32.
33.
Ohne ZusammenfassungFERDINAND FLURY zum 60. Geburtstag gewidmet. 相似文献
34.
文章从创新及创新型人才的概念入手,通过调研指出,目前临床医学人才培养存在的主要问题,提出在新时期要转变教育教学观念、强化创新意识教育、增强创新思维训练、着力创新人格塑造,以培养创新型临床医学人才。 相似文献
35.
目的:探讨化合物YD383和YD439对STAT6信号传导通路的作用是否具有特异性.方法:通过瞬时转染的方法将分别依赖于STAT1和STAT6活性的带有荧光素酶报告基因的质粒转染至HeLa细胞株,两种细胞株在各自相应的细胞因子(IFN-γ或IL-4)刺激下激活JAK-STAT1或JAK-STAT6信号传导通路.通过测定荧光素酶的活性来评价细胞株在化合物存在的情况下报告基因的表达.结果:YD383和YD439均能降低相应细胞因子刺激引起的报告基因的表达,并且具有剂量依赖性.随着化合物剂量的增加,报告基因的表达降低(P<0.05).但化合物引起的两种转染细胞报告基因表达降低的差异比较无统计学意义(P>0.05).结论:两种化合物对JAK-STAT1和JAK-STAT6信号传导通路均有抑制作用,对JAK-STAT6通路的抑制不具有特异性. 相似文献
36.
目的初步探寻人外周血自然杀伤细胞(Nature Killer,NK)杀伤细胞免疫球蛋白样受体(Killer Cell Immnoglobulin-Like Receptor,KIR3DL1)表达可能存在的microRNA(miR)调控机制。方法利用生物信息学方法,从miR信息库中筛选出可能与KIR3DL1相关的miRs,构建含KIR3DL1 3’非翻译区(UTR)的PGL3质粒,分别将含相应miR的PcDNA3.0质粒与前者共转染293T细胞,通过荧光素酶报告实验及之后的突变实验筛选出可能调控KIR3DL1的miR。结果通过TARGET SCAN信息库筛选了miR-146b等10个miR;转染miR-146b后,荧光素酶活性下降最多(61.3%),突变其KIR3DL1 3’UTR靶位点后荧光素酶活性恢复(91.4%)。结论 miR-146b可与KIR3DL1’UTR在靶位点特异结合,很可能参与KIR3DL1表达的调控。 相似文献
37.
Stephens RW; Golder JP; Fayle DR; Hume DA; Hapel AJ; Allan W; Fordham CJ; Doe WF 《Blood》1985,66(2):333-337
Adherent monolayer cultures of human blood monocytes, peritoneal macrophages, bone marrow macrophages, and colonic mucosa macrophages were examined for their ability to produce and secrete minactivin, a specific inactivator of urokinase-type plasminogen activator. All except colonic mucosa macrophages produced and secreted appreciable amounts of minactivin, but only blood monocytes were stimulated by muramyl dipeptide (adjuvant peptide) to increase production. The minactivin from each of these populations could be shown to preferentially inhibit urokinase-type plasminogen activator and not trypsin, plasmin, or "tissue"-type plasminogen activator (HPA66). A plasminogen-activating enzyme present in monocyte cultures appeared unaffected by the presence of minactivin and could be shown to be regulated independently by dexamethasone. 相似文献
38.
Use of multiple T cell-directed intact ricin immunotoxins for autologous bone marrow transplantation 总被引:7,自引:0,他引:7
The monoclonal antibodies (MoAb) T101, G3.7, 35.1, and TA-1 were conjugated to intact ricin using a thioether linkage. These MoAb detect, respectively, the CD5[gp67], CD7[p41], CD2[p50], and [gp95, 170] determinants that are found in the vast majority of cases of T cell acute lymphocytic leukemia (T-ALL). The resulting immunotoxins (ITs) and an equimolar mixture of these ITs were evaluated as potential purgative reagents for autologous transplantation in T-ALL. Leukemic cell lines were used to compare the kinetics of protein synthesis inactivation mediated by each IT. The cells were treated with IT in the presence of lactose in order to block the native binding of ricin. The observed rates of protein synthesis inactivation correlated with target antigen expression detected by fluorescence-activated cell sorter analysis. Of the four ITs, T101-ricin (T101-R) exhibited the fastest rate of inactivation, followed in order by G3.7-ricin, TA-1-ricin, and 35.1-ricin. At concentrations greater than 300 ng/mL, a cocktail containing an equimolar amount of all four ITs (referred to as the four- IT cocktail) exhibited kinetics that were as fast or faster than those of T101-R. The long-term cytotoxic effects of individual ITs and the four-IT cocktail were evaluated using a sensitive clonogenic assay. Each IT was specifically cytotoxic and inhibited 1 to 4 logs of clonogenic leukemic cells at doses (300 to 600 ng/mL) that can be used clinically. The four-IT cocktail was highly cytotoxic; a concentration of 300 ng/mL inhibited greater than 4 logs of leukemic cells while sparing the majority of committed (CFU-GM, CFU-E) and pluripotent (CFU- GEMM) hematopoietic stem cells. The determination of both short-term kinetics of protein synthesis inactivation and longer-term inhibition of clonogenic growth allowed new insight into cell killing by IT. Our results suggest that ITs continue to act on clonogenic target cells for a period of three to five days. Interestingly, the four-IT cocktail was not as potent against clonogenic leukemic cells as T101-R alone, although it exhibited kinetics of protein synthesis inhibition that were as fast as those of T101-R alone. This finding suggests that internalized ITs may differ in the length of time they remain active within the cell. Our results also demonstrate the importance of using several different assays to evaluate IT reagents. 相似文献
39.
40.
波尔山羊重复超排效果的研究 总被引:8,自引:1,他引:8
对 2 0只波尔山羊实施两次超排处理。其结果如下 :1.第 1次超排处理时 2 0只供体羊全部发情并进行采卵 ,超排有效率为 10 0 % ;平均排卵数为 2 0 .2 5枚 /只 ,平均采集胚胎数 19.2 5枚 /只 ,平均采集可用胚胎数为 17.3枚 /只 ;第 2次超排处理时有 3只羊推迟发情 ,超排有效率为 85 % ;平均排卵数 19.2 9枚 /只 ,平均采集胚胎数 18.5 3枚 /只 ,平均采集可用胚胎数 17.35枚 /只 ;2 .两次超排所获得的平均可用胚胎数差异不显著(p >0 .0 5 )。 相似文献