全文获取类型
收费全文 | 22820篇 |
免费 | 2265篇 |
国内免费 | 1340篇 |
专业分类
耳鼻咽喉 | 233篇 |
儿科学 | 293篇 |
妇产科学 | 262篇 |
基础医学 | 2544篇 |
口腔科学 | 439篇 |
临床医学 | 2925篇 |
内科学 | 3235篇 |
皮肤病学 | 244篇 |
神经病学 | 1123篇 |
特种医学 | 795篇 |
外国民族医学 | 6篇 |
外科学 | 2460篇 |
综合类 | 4136篇 |
现状与发展 | 6篇 |
一般理论 | 6篇 |
预防医学 | 1710篇 |
眼科学 | 547篇 |
药学 | 2158篇 |
31篇 | |
中国医学 | 1534篇 |
肿瘤学 | 1738篇 |
出版年
2024年 | 122篇 |
2023年 | 396篇 |
2022年 | 1037篇 |
2021年 | 1263篇 |
2020年 | 937篇 |
2019年 | 711篇 |
2018年 | 767篇 |
2017年 | 680篇 |
2016年 | 644篇 |
2015年 | 924篇 |
2014年 | 1100篇 |
2013年 | 1137篇 |
2012年 | 1652篇 |
2011年 | 1673篇 |
2010年 | 1187篇 |
2009年 | 1042篇 |
2008年 | 1301篇 |
2007年 | 1289篇 |
2006年 | 1253篇 |
2005年 | 1075篇 |
2004年 | 849篇 |
2003年 | 833篇 |
2002年 | 751篇 |
2001年 | 550篇 |
2000年 | 569篇 |
1999年 | 483篇 |
1998年 | 299篇 |
1997年 | 252篇 |
1996年 | 209篇 |
1995年 | 218篇 |
1994年 | 180篇 |
1993年 | 98篇 |
1992年 | 152篇 |
1991年 | 118篇 |
1990年 | 95篇 |
1989年 | 79篇 |
1988年 | 84篇 |
1987年 | 74篇 |
1986年 | 55篇 |
1985年 | 45篇 |
1984年 | 36篇 |
1983年 | 24篇 |
1982年 | 18篇 |
1981年 | 15篇 |
1980年 | 18篇 |
1979年 | 31篇 |
1977年 | 16篇 |
1973年 | 11篇 |
1972年 | 10篇 |
1971年 | 9篇 |
排序方式: 共有10000条查询结果,搜索用时 10 毫秒
31.
Liposome-mediated transfer of vascular endothelial growth factor cDNA augments survival of random-pattern skin flaps in the rat. 总被引:6,自引:0,他引:6
Paul Y Liu Wenjing Tong Kan Liu Sang Hoon Han Xiao Tian Wang Evangelos Badiavas Kimberly Rieger-Christ Ian Summerhayes 《Wound repair and regeneration》2004,12(1):80-85
Tissue engineering is an application for gene therapy that is in its infancy. We show that simple liposomal-mediated gene transfer could result in a potentially useful biological effect in the field of wound healing. cDNA encoding the 165 amino acid form of vascular endothelial growth factor complexed to commercially available liposomes was injected into rat skin 1 week before raising a random pattern 3 x 10 cm flap. The flap survival was enhanced by 14 percent, and was accomplished without accessing the arterial inflow of the territory. These results were statistically significant (p<0.002) and reproducible. No adverse effects were seen. Histological analysis of the angiogenesis localized much of the new vessel formation to the area around the hair follicles. Polymerase chain reaction amplification of extracted flap tissue confirmed the presence of the transgene. 相似文献
32.
目的:探讨超声造影诊断肝孤立性坏死结节的价值。材料和方法:回顾分析了12例肝孤立性坏死结节的超声造影表现。结果:12例病灶造影动脉期、门脉期、实质期均无增强,呈边界清晰的造影剂充盈缺损区。结论:超声造影对诊断肝孤立性坏死结节具有较高的价值。目的:探讨超声造影诊断肝孤立性坏死结节的价值。材料和方法:回顾分析了12例肝孤立性坏死结节的超声造影表现。结果:12例病灶造影动脉期、门脉期、实质期均无增强,呈边界清晰的造影剂充盈缺损区。结论:超声造影对诊断肝孤立性坏死结节具有较高的价值。 相似文献
33.
The influence of sex steroids and the dopaminergic system on the in vivo modulation of prolactin (PRL) mRNA levels was investigated by quantitative in situ hybridization in the male rat anterior pituitary gland. In situ hybridization was performed using a [35S]-labeled cDNA probe encoding PRL. Orchiectomy performed 14 days earlier did not modify PRL mRNA levels. In orchiectomized rats treatment with the dopaminergic agonist bromocriptine for 14 days decreased PRL mRNA levels by 30%, while in intact animals the same treatment did not induce any changes in PRL mRNA levels. Administration of the dopamine D2 receptor antagonist haloperidol in both intact and orchiectomized rats induced a 4-fold increase in mRNA levels. Administration of dihydrotestosterone to orchiectomized animals which had been treated or not with haloperidol or bromocriptine did not modify PRL mRNA levels. In orchiectomized animals administration of 17ß-estradiol (0.25 μg twice daily) for 14 days caused a 4-fold increase in amounts of PRL mRNA. Administration of bromocriptine to 17ß-estradiol-treated animals induced a 15% decrease of PRL mRNA levels compared to those obtained by 17ß-estradiol administered alone. The concomitant administration of 17ß-estradiol and haloperidol resulted in a 50% increase in PRL mRNA levels compared to those measured in animals treated with haloperidol alone. The present results clearly demonstrate that in vivo estrogen as well as dopamine-mediated mechanisms play a regulatory role in PRL mRNA levels in the male rat. 相似文献
34.
前列腺癌中PIM-1的表达及其临床意义 总被引:4,自引:0,他引:4
目的 探讨PIM-1在前列腺癌中的表达及临床意义。方法 逆转录-聚合酶链反应(RT—PCR)半定量分析2例良性前列腺增生(BPH)和5例前列腺癌(PCa)组织标本中PIM-1mRNA表达,免疫组织化学法检测20例BPH、20例高分级前列腺上皮内瘤(HGPIN)和42例PCa组织标本中PIM-1蛋白表达水平,染色结果分为阴性、弱阳性、阳性和强阳性。结果 5例PCa组织PIM-1mRNA表达相对值分别为0.63、0.55、0.42、0.91、0.76,2例BPH中其相对值为0.26、0.27。BPH、HGPIN和PCa组织中PIM-1蛋白阴性表达率分别为60%(12/20)、20%(4/20)和2%(1/42),弱阳性表达率分别为40%(8/12)、20%(4/20)和12%(5/42),阳性列强阳性表达率分别为0(0/20)、60%(12/20)和86%(36/42),PCa中PIM-1蛋白表达水平高于HGPIN和BPH(P值均〈0.05)。PIM-1蛋白表达水平随PCa的临床分期和病理分级增高而增强,在有和没有淋巴结转移PCa组织中PIM-1强阳性表达率分别为70%(7/10)、25%(8/32),差异有统计学意义(P〈0.05)。结论PIM-1高表达可能与PCa发生和发展相关,PIM-1表达水平与PCa分期、Gleason评分呈正相关,可能成为PCa预后判断的肿瘤标志物。 相似文献
35.
双J管临床应用及美蓝在置管术中的作用 总被引:1,自引:0,他引:1
目的探讨双J管(双J输尿管支架管)在泌尿系疾病治疗中的应用效果以及美蓝在置放术中的作用。方法对215例患者采用放置双J管作内支架和内引流治疗,近期48例术中以美蓝协助定位。结果术后留置尿管5~7d,无切口感染、尿瘘等并发症。术后1~3个月拔除双J管,随访3~6个月,肾功能、肾积水明显好转,吻合口通畅。以美蓝协助定位者无双J管上移致拔管困难。结论双J管具有内支架和内引流作用,操作简单,引流效果好,并发症少,缩短住院时间。以美蓝协助定位,值得推广应用。 相似文献
36.
Wing‐Hong Li Moon‐Tong Cheung Candace N.S. Ho Ting‐Pong Fung Kai‐Ming Ko Kelvin K.W. Yau 《Surgical Practice》2007,11(4):138-143
Aim: To examine the survival benefit of liver and lung resection for colorectal metastasis and the potential prognostic factors that affect patient survival. Methods: All patients who had resection of lung or liver metastasis for colorectal metastasis in Queen Elizabeth Hospital, Hong Kong from 1995 to 2004 were retrospectively reviewed. The overall and disease‐free survival was analysed, in particularly between liver and lung metastasis. All factors that may have affected the survival were entered into Cox's proportional hazards regression model to identify significant variables associated with survival. Results: At 5 years, the overall survival of patients who had resection of lung and liver metastasis was 44% and 38%, respectively; the disease‐free survival was 26% and 24%, respectively. Overall and disease‐free survival of patients with resection of lung metastasis was comparable to those with resection of liver metastasis. The differentiations of primary tumour and time to metastasis were shown to be significant prognostic factors influencing overall survival. Those patients with systemic chemotherapy after resection of colorectal metastasis demonstrated a significantly higher probability of overall survival. Conclusion: Resection of lung and liver metastases from colorectal origin was safe and both procedures improved survival. The use of chemotherapy after resection of metastasis significantly improved the overall survival. 相似文献
37.
The first 150 words of the full text of this article appear below. Key points. . . [Full Text of this Article]
Nerve agents
AChE inhibitionOther cholinesterasesPhysical propertiesLatency and toxicityPharmacological propertiesClinical manifestationsTreatmentPyridostigmineAtropinePralidoxime
- Chemical personal protective equipment must be wornwhen in contact with contaminated casualties.
- Recognizing theclinical features of chemical warfare agent poisoning allowssupportive treatment and appropriate antidotes to be promptlyadministered.
- The mnemonic DUMBELS describes the muscarinicfeatures of the nerve agent poisoning toxidrome.
- There areeffective antidotes for poisoning with nerve agents, blood agents(metabolic poisons), botulinum toxin and kolokol-1.
- There areno specific antidotes for blistering agents (vesicants) andchoking agents.