全文获取类型
收费全文 | 1230篇 |
免费 | 46篇 |
国内免费 | 81篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 67篇 |
妇产科学 | 9篇 |
基础医学 | 135篇 |
口腔科学 | 23篇 |
临床医学 | 221篇 |
内科学 | 293篇 |
皮肤病学 | 33篇 |
神经病学 | 27篇 |
特种医学 | 300篇 |
外科学 | 58篇 |
综合类 | 26篇 |
预防医学 | 28篇 |
眼科学 | 6篇 |
药学 | 71篇 |
肿瘤学 | 59篇 |
出版年
2022年 | 5篇 |
2021年 | 8篇 |
2019年 | 11篇 |
2018年 | 7篇 |
2017年 | 9篇 |
2016年 | 10篇 |
2015年 | 18篇 |
2014年 | 11篇 |
2013年 | 26篇 |
2012年 | 10篇 |
2011年 | 14篇 |
2010年 | 48篇 |
2009年 | 45篇 |
2008年 | 18篇 |
2007年 | 56篇 |
2006年 | 17篇 |
2005年 | 25篇 |
2004年 | 10篇 |
2003年 | 12篇 |
2002年 | 17篇 |
2001年 | 16篇 |
2000年 | 19篇 |
1999年 | 24篇 |
1998年 | 93篇 |
1997年 | 88篇 |
1996年 | 109篇 |
1995年 | 84篇 |
1994年 | 88篇 |
1993年 | 74篇 |
1992年 | 21篇 |
1991年 | 30篇 |
1990年 | 27篇 |
1989年 | 32篇 |
1988年 | 36篇 |
1987年 | 27篇 |
1986年 | 34篇 |
1985年 | 32篇 |
1984年 | 13篇 |
1983年 | 21篇 |
1982年 | 20篇 |
1981年 | 21篇 |
1980年 | 17篇 |
1979年 | 4篇 |
1978年 | 9篇 |
1977年 | 14篇 |
1976年 | 13篇 |
1975年 | 7篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1966年 | 1篇 |
排序方式: 共有1357条查询结果,搜索用时 0 毫秒
101.
ChintamaniEmail author Vinay?Singhal JP?Singh Ashima?Lyall Sunita?Saxena Anju?Bansal 《BMC cancer》2004,4(1):48
Background
Neo-adjuvant chemotherapy is an integral part of multi-modality approach in the management of locally advanced breast cancer and it is vital to predict the response in order to tailor the regime for a patient. The common final pathway in the tumor cell death is believed to be apoptosis or programmed cell death and chemotherapeutic drugs like other DNA-damaging agents act on rapidly multiplying cells including both the tumor and the normal cells by following the same common final pathway. This could account for both the toxic effects and the response. Absence or decreased apoptosis has been found to be associated with chemo resistance. The change in expression of apoptotic markers (Bcl-2 and Bax proteins) brought about by various chemotherapeutic regimens is being used to identify drug resistance in the tumor cells. A prospective clinical study was conducted to assess whether chemotherapy induced toxic effects could serve as reliable predictors of apoptosis or response to neo-adjuvant chemotherapy in patients with locally advanced breast cancer. 相似文献102.
高效液相色谱法测定寒痹停片中士的宁含量 总被引:6,自引:0,他引:6
目的:建立用HPLC测定寒痹停片中士的含量的方法。方法:氰基柱;流动相-甲醇-水-三乙胺-乙酸(9800:155:15:30);紫外检测波长254nm。结果:在4~20ug/ml范围内,标准曲线回归方程为:Y=-2803+8967x(r=0.9997),RSD=1.65%?加样回收率的平均值为99.82%。结论:实验表明,这是一个适用于生产控制和产品质量检验的简单、快速、准确的方法。 相似文献
103.
104.
105.
JP Damsin JY Zambelli R Ma J Roume F Colonna L Hannoun 《Surgical and radiologic anatomy : SRA》1995,17(1):13-17
Summary Varus deformity of the knee is common in young children who have suffered from fulminating purpura. This study was directed at the anatomic features of the vascularisation of the upper end of the tibia that might account for such deformation. It was based on the dissection of 28 anatomic specimens prepared by injection of Indian ink into the vascular trunk. 16 specimens were diaphanised for better analysis of the intracartilaginous distribution of the vessels. The study showed that the vascularisation of the medial condyle of the tibia is poor and of terminal nature, which may explain the occurrence of ischemic growth disorders following fulminating purpura.
Etude de la vascularisation artérielle du condyle médial du tibia chez le foetus
Résumé Les déformations en varus du genou chez les jeunes enfants ayant présenté un purpura fulminans sont fréquentes. Ce travail a pour objet de rechercher les caractéristiques anatomiques de la vascularisation de l'extrémité supérieure du tibia qui peuvent expliquer ces déformations. L'étude porte sur la dissection de 28 pièces anatomiques préparées par injection de l'axe vasculaire à l'encre de Chine. Pour mieux analyser la répartition intra-cartilagineuse des vaisseaux, 16 pièces ont été diaphanisées. Cette étude montre que la vascularisation du condyle médial du tibia est pauvre, de type terminal, ce qui peut expliquer la survenue de troubles de croissance ischémiques dans les suites d'un purpura fulminans.相似文献
106.
107.
3-Hydroxypropyl flufenamide (Flu-HPA) is one of a series of flufenamic acid derivatives that enhances blood clot lysis in vitro. Studies of possible mechanisms of action of Flu-HPA were undertaken. The profibrinolytic activity of Flu-HPA in clot lysis assays was found to be dependent on plasminogen. The influence of Flu-HPA on the ability of purified alpha 2-antiplasmin to inhibit purified plasmin was studied. Plasmin activity was determined using 125I-fibrin plates or the spectrophotometric tripeptide substrate, Val-Leu-Lys-paranitroanilide. At Flu-HPA concentrations greater than 1 mM, the inhibitory activity of alpha 2-antiplasmin was abolished in a time-dependent and concentration- dependent manner. The influence of Flu-HPA on the ability of purified Cl inhibitor to inhibit purified plasma kallikrein and beta-Factor XIIa was also studied. Cl inhibitor activity was abolished by Flu-HPA at concentrations greater than 2 mM. Notably, Flu-HPA up to 60 mM did not affect the amidolytic activities of plasmin, kallikrein, or beta-Factor XIIa. Flu-HPA did not release enzyme activity from preformed complexes of either alpha 2-antiplasmin and plasmin of Cl inhibitor and kallikrein. A water-soluble derivative of flufenamic acid, N-flufenamyl- glutamic acid, also inactivated alpha 2-antiplasm and Cl inhibitor. This inactivation was shown to be reversible. These results indicate that synthetic fibrinolytic compounds such as flufenamic acid derivatives may promote fibrinolysis by directly inactivating alpha 2- antiplasmin and Cl inhibitor. 相似文献
108.
Molecular characterization of human factor XSan Antonio 总被引:1,自引:0,他引:1
Enzymatic amplification technique was used to isolate all eight exons and sequences around the splice junctions, putative promoter, and polyadenylation sites of human factor X DNA from a patient with factor X deficiency. Two genetic changes in factor X have been observed in this patient. The patient is most likely a compound heterozygote since there is only 14% activity associated with factor X. A point mutation that resulted in the substitution of cysteine (TGC) for arginine (CGC) at amino acid 366 was found in exon VIII of one allele of the factor X gene. This mutation, which occurs in the catalytic domain, can affect the formation of a disulfide bridge and thus could result in a reduction in factor X activity. Sequencing all the regions revealed a second mutation: a deletion of one nucleotide (TCCT to TCT) in exon VII that would cause a frame shift at amino acid 272 followed by termination. We have also shown that the point mutation in exon VIII creates an ApaL1 restriction site and destroys the HinP1 site. Enzymatic DNA amplification followed by restriction digestion provides a quick, reliable, and sensitive method for carrier detection and antenatal diagnosis in affected kindreds. This is the first characterization of factor X deficiency at the molecular level. We propose to name this mutation Factor XSan Antonio. 相似文献
109.
110.
为探讨体外循环(CPB)导致心脏植物神经系统(CAS)损伤的机理,了解温血心停跳液能否防止CPB后心率变异性(HRV)的降低,采用对照方法观察了温血心停跳液与冷晶体心停跳液对狗HRV的影响。结果显示:CPB后温血心停跳液组(WB组)和冷晶体心停跳液组(CC组)的全频谱(TP)、低频(LF)和高频(HF)均较术前明显降低(P<0.05),而且CC组比WB组降低更明显(P<0.05),但LF/HF在组内及组间均无明显变化(P>0.05)。CPB后24小时平均心率(MHR)明显增加(P<0.05),且CC组高于WB组(P<0.05)。本研究表明:采用温血心停跳液或冷晶体心停跳液的CPB不会干扰CAS平衡,但均能使HRV降低,温血心停跳液不能防止HRV损害。 相似文献