全文获取类型
收费全文 | 2383篇 |
免费 | 135篇 |
国内免费 | 45篇 |
专业分类
耳鼻咽喉 | 23篇 |
儿科学 | 60篇 |
妇产科学 | 47篇 |
基础医学 | 273篇 |
口腔科学 | 46篇 |
临床医学 | 275篇 |
内科学 | 516篇 |
皮肤病学 | 112篇 |
神经病学 | 147篇 |
特种医学 | 234篇 |
外科学 | 290篇 |
综合类 | 28篇 |
一般理论 | 1篇 |
预防医学 | 195篇 |
眼科学 | 9篇 |
药学 | 120篇 |
中国医学 | 2篇 |
肿瘤学 | 185篇 |
出版年
2023年 | 25篇 |
2022年 | 55篇 |
2021年 | 104篇 |
2020年 | 45篇 |
2019年 | 76篇 |
2018年 | 80篇 |
2017年 | 56篇 |
2016年 | 62篇 |
2015年 | 69篇 |
2014年 | 83篇 |
2013年 | 114篇 |
2012年 | 130篇 |
2011年 | 158篇 |
2010年 | 79篇 |
2009年 | 67篇 |
2008年 | 116篇 |
2007年 | 135篇 |
2006年 | 118篇 |
2005年 | 101篇 |
2004年 | 89篇 |
2003年 | 94篇 |
2002年 | 66篇 |
2001年 | 17篇 |
2000年 | 11篇 |
1999年 | 23篇 |
1998年 | 38篇 |
1997年 | 38篇 |
1996年 | 42篇 |
1995年 | 35篇 |
1994年 | 50篇 |
1993年 | 26篇 |
1992年 | 12篇 |
1991年 | 16篇 |
1990年 | 15篇 |
1989年 | 41篇 |
1988年 | 43篇 |
1987年 | 48篇 |
1986年 | 30篇 |
1985年 | 24篇 |
1984年 | 23篇 |
1983年 | 17篇 |
1982年 | 14篇 |
1981年 | 14篇 |
1980年 | 14篇 |
1979年 | 4篇 |
1978年 | 4篇 |
1977年 | 4篇 |
1976年 | 8篇 |
1975年 | 5篇 |
1927年 | 3篇 |
排序方式: 共有2563条查询结果,搜索用时 0 毫秒
1.
2.
SUMMARY A case congenital dislocation of both knees and dislocation of the left hip in an infant whose mother had a chronic amniotic fluid leakage after mid-trimester amniocentesis. 相似文献
3.
Noah Simmons Ognjen Brborovic Tozija Fimka Brian D Robie David L Bull Mome Spasovski Edward L Baker 《JPHMP》2005,11(4):351-356
The political disintegration of former Yugoslavia inaugurated in 1991 resulted in the decentralization of health systems in the federation's successor nation-states. Efforts by the Open Society Institute improved public health planning and management needs consequent to health sector changes. Beginning in Croatia in 2001, the Institute developed ongoing collaborations between Andrija Stampar School of Public Health and the US Centers for Disease Control and Prevention. In 2003 and 2004, it expanded its project to include the republics of Macedonia and of Serbia and Montenegro. 相似文献
4.
Noah A Goldman Ellen B Katz Alan S Glenn Richard H Weldon Joan G Jones Uticia Lynch Melissa J Fezzari Carolyn D Runowicz Gary L Goldberg Maureen J Charron 《Modern pathology》2006,19(11):1429-1436
Glucose is provided to cells by a family of glucose transport facilitators known as GLUTs. These transporters are expressed in a tissue specific manner and are overexpressed in many primary tumors of these tissues. Regulation of glucose transport facilitator expression has been demonstrated in endometrial tissue and endometrial adenocarcinoma. The following experiments were conducted to quantify and localize the expression of GLUT1 and GLUT8 in benign endometrium and compare this expression to endometrial cancer. Endometrial tissue samples were obtained from random hysterectomy specimens of patients with benign indications for surgery and endometrial cancer. Immunoblot and immunolocatization studies were performed using GLUT1 and GLUT8 specific antisera. Endometrial samples from 65 women who had undergone hysterectomy were examined (n=38 benign, n=27 malignant). A 44 and a 35.4 kDa immunoreacive species was demonstrated in endometrium and endometrial cancer for GLUT1 and GLUT8, respectively. Upregulation of GLUT1 expression was demonstrated with increasing grade of tumors (P<0.002). GLUT8 expression was increased in all tumor subtypes compared to atrophic endometrium (P<0.001). Apical localization by GLUT1 and GLUT8 was demonstrated in endometrial glands. GLUT1 and GLUT8 demonstrated diffuse intracellular localization in the cancer subtypes. GLUT1 and GLUT8 are expressed in both human endometrium and endometrial cancer. There appears to be a step-wise progression in GLUT1 and GLUT8 expression as tumor histopathology worsens. GLUT1 and GLUT8 may be important markers in tumor differentiation, as well as providing energy to rapidly dividing tumor cells. 相似文献
5.
6.
高效液相色谱法测定右旋儿茶素血浆浓度及药代动力学参数 总被引:1,自引:0,他引:1
本文建立了体液中右旋儿茶素的RP-HPLC测定方法。采用C_(18)键合相硅胶为填料的固相提取柱进行样品预处理,右旋儿茶素的提取回收率为79.8%.应用二极管阵列检测器对色谱峰纯度进行鉴定。该法精密度好,方法回收率近100%,日内、日间的变异系数为2.4~5.6%,血浓69.6~1160 ng/ml范围内呈线性关系,r=0.9993。家兔静注右旋儿茶素18mg/kg,其药代动力学过程符合二室模型,分布相半衰期为0.129 h,消除相半衰期为1.19h。 相似文献
7.
8.
石杉碱甲类似物的研究II.N-甲基吡啶酮石杉碱甲类似物的合成 总被引:4,自引:1,他引:3
石杉碱甲(1)是从中草药石杉属植物千层塔(Lycopodium serratum Thunb.)中分得的一种高效可逆的乙酰胆碱酯酶抑制剂,临床试验证实它对早老性痴呆症有显著疗效。本文报道N-甲基吡啶酮石杉碱甲类似物2和3的合成。2-甲氧基-5-甲氧羰基-11-亚甲基-5,9-甲撑环辛-7-烯并吡啶(9)在乙腈中用三甲基氯硅烷和碘化钠选择性脱保护以定量的产率得吡啶酮10,再用甲醇钠和碘甲烷甲基化得N-甲基吡啶酮11,11经碱性水解,Curtius重排和氨基的脱保护得N-甲基吡啶酮石杉碱甲类似物2。通过类似的途径从中间体2-甲氧基-5-甲氧羰基-7-甲基-11-酮-5,9-甲撑环辛-7-烯并吡啶(14)合成了类似物3。类似物2和3的乙酰胆碱酯酶抑制活性均低于天然石杉碱甲。 相似文献
9.
10.
Mutations in the retinal guanylate cyclase (RETGC-1) gene in dominant cone-rod dystrophy 总被引:3,自引:0,他引:3
Kelsell RE; Gregory-Evans K; Payne AM; Perrault I; Kaplan J; Yang RB; Garbers DL; Bird AC; Moore AT; Hunt DM 《Human molecular genetics》1998,7(7):1179-1184
The dominant cone-rod dystrophy gene CORD6 has previously been mapped to
within an 8 cM interval on chromosome 17p12-p13. The retinal- specific
guanylate cyclase gene (RETGC-1), which maps to within this genetic
interval and previously was implicated in Leber's congenital amaurosis, was
screened for mutations within this family and in a panel of small families
and individuals with various cone and cone- rod dystrophy phenotypes. A
missense mutation (E837D) was identified in affected members of the CORD6
family, as well as a second missense mutation (R838C) in three other
families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene
to be implicated in cone-rod dystrophy and this is the first report of
dominant mutations in this gene.
相似文献