首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2023篇
  免费   65篇
  国内免费   32篇
耳鼻咽喉   14篇
儿科学   25篇
妇产科学   13篇
基础医学   244篇
口腔科学   4篇
临床医学   191篇
内科学   181篇
皮肤病学   3篇
神经病学   17篇
特种医学   401篇
外科学   328篇
综合类   252篇
预防医学   75篇
眼科学   1篇
药学   135篇
  3篇
中国医学   85篇
肿瘤学   148篇
  2023年   6篇
  2022年   14篇
  2021年   29篇
  2020年   22篇
  2019年   16篇
  2018年   19篇
  2017年   19篇
  2016年   40篇
  2015年   62篇
  2014年   89篇
  2013年   99篇
  2012年   77篇
  2011年   82篇
  2010年   94篇
  2009年   95篇
  2008年   115篇
  2007年   112篇
  2006年   121篇
  2005年   94篇
  2004年   79篇
  2003年   71篇
  2002年   56篇
  2001年   69篇
  2000年   49篇
  1999年   65篇
  1998年   64篇
  1997年   42篇
  1996年   53篇
  1995年   38篇
  1994年   28篇
  1993年   34篇
  1992年   23篇
  1991年   22篇
  1990年   26篇
  1989年   30篇
  1988年   21篇
  1987年   10篇
  1986年   16篇
  1985年   16篇
  1984年   15篇
  1983年   5篇
  1982年   11篇
  1981年   18篇
  1980年   17篇
  1979年   7篇
  1978年   7篇
  1977年   3篇
  1976年   4篇
  1975年   3篇
  1970年   5篇
排序方式: 共有2120条查询结果,搜索用时 15 毫秒
1.
Mammary carcinoma (MC) is one of most common malignancy in women, and ring finger protein 2 (RNF2) possesses various roles in vast human tumors. In MC tissues as well as in cell lines RNF2 exhibited high expression, had significant association with tumor size, lymph node status, TNM stage, patients’ poor survival, and promoted cell proliferation, colony formation, cell migration and invasion of MC cell lines which was mediated by downregulation of E-cadherin protein. These data reveal that RNF2 protein plays a vital role in the development of MC and may be a potential therapy target of MC.  相似文献   
2.
KGF在乳腺癌的表达与临床意义   总被引:1,自引:0,他引:1  
目的:探讨KGF蛋白在人乳腺癌的表达与意义,与临床病理因素及生物学指标的相关性。方法: 采用免疫组化方法检测KGF在63例乳腺癌组织中的表达,并与正常乳腺组织对照。结果:63例乳腺癌组织中34例肿瘤细胞表达KGF(54.0%),正常乳腺上皮细胞未表达(P<0.01),在乳腺癌间质细胞和正常乳腺组织间质细胞表达率分别为34.9%和16.7%(P>0.05)。其在肿瘤细胞中的表达与低分化相关,与ER、PR呈负相关,与Ki-67呈正相关,与Ki-67的协同表达与淋巴结转移正相关。结论: KGF在乳腺癌肿瘤细胞的表达可能促进乳腺癌的发生发展,并且与低分化、预后不良有关。  相似文献   
3.
Purpose: To assess the accuracy of intraarterial measurement of transstenotic pressure gradients for the detection of hemodynamically suboptimal iliac angioplasty. Methods: In 14 patients, referred for diagnostic angiography, mean pressure gradients in the aorta and iliac artery were obtained twice, using a double-sensor pressure catheter. Additional iliac measurements were performed during pharmacologically induced flow augmentation. Repeatability was assessed by calculation of the mean difference plus standard deviation (MD ± SD) and repeatability coefficient (2 × SD). These results were extrapolated to 137 iliac angioplasty procedures with secondary stenting where there was a residual pressure gradient > 10 mmHg. Results: MD ± SD for repeated measurements at rest and during flow augmentation were 0 ± 2 mmHg and 1 ± 3 mmHg, respectively. Repeatability coefficients were 3 and 6 mmHg. Mean pressure gradients after hemodynamically insufficient angioplasty were 8 ± 7 mmHg at rest and 17 ± 5 mmHg following vasodilatation. Inaccurate pressure recordings may have led to inappropriate stent placement in less than 2.5%, and inappropriate denial of stent placement in less than 5% of the lesions. Conclusion: Variability of intraarterial pressure measurements has little consequence in the detection of hemodynamically significant stenosis after angioplasty. Received: 0/00/00/Accepted: 0/00/00  相似文献   
4.
Ivalon (polyvinyl alcohol) is a commonly used embolic agent, generally considered to be permanent. In a patient with the carcinoid syndrome, embolization of hepatic metastases with Ivalon failed to produce permanent occlusion, and recurrent tumor was supplied by many of the same small arteries identified on the original arteriogram. Occasionally, Ivalon may have only a temporary occlusive effect. A possible explanation for this phenomenon is proposed.  相似文献   
5.
乳腺占位病变的高场强MRI诊断价值   总被引:1,自引:1,他引:0  
目的 :总结乳腺良恶性占位病变在高场强MRI的影像表现 ,评价高场强MRI对乳腺良恶性病变的诊断价值。方法 :搜集1996~ 2 0 0 4年间经手术病理证实的 4 3例乳腺良恶性占位病变的MRI资料 ,分析其影像表现。结果 :典型乳腺良、恶性病变 ,高场强MR平扫即能准确诊断 ,而部分非典型良、恶性病灶 ,增强扫描形态、信号变化也有一定的重叠。结论 :MRI技术能够充分显示病变形态及与周围组织结构之间的关系 ,是建议活检或预防性手术的最有力的依据。但是 ,MRI平扫、增强技术对乳腺非典型病变 ,仍然有局限性  相似文献   
6.
本文报告乳腺积乳囊肿43例。讨论了发病原因及病理,特别提出局部肿块波动感试验阳性,A超检查显示液平段,试穿抽出乳汁,对诊断有肯定价值;治疗以手术切除为主,仅有7例穿刺抽吸乳汁得以治愈。  相似文献   
7.
Embolisation of a mycotic aneurysm of the anterior pancreaticoduodenal arcade was performed in an emergency situation using a microcatheter and tissue adhesive, after unsuccessful surgical therapy. The polymerising agent occluded the outflow vessel, the aneurysm and the feeding artery successfully. Correspondence to: F. Hammer  相似文献   
8.
超细纤维乳管镜引导下乳管内肿瘤切除术   总被引:8,自引:5,他引:3  
目的探讨超细纤维乳管镜引导下乳管内肿瘤切除术的应用价值。方法对312例乳头溢液进行乳管镜检查,其中乳管内发现肿瘤者行手术治疗。利用乳管镜冷光源的皮肤透照点定象限,乳管扩张器探针定乳管走行方向,亚甲蓝染色定乳管末梢的分布。结果78例导管内发现肿瘤:单发性乳头状瘤68例,乳头状瘤病5例,导管内癌5例。28.2%(22/78)的病灶位于总导管,48.7%(38/78)位于导管Ⅰ级分支,17.9%(14/78)位于Ⅱ级分支,位于Ⅲ级和Ⅳ级分支病灶仅占3.8%(3/78)和1.3%(1/78)。病灶距乳头开口的平均距离为2.5cm(1~5cm)。78例均行手术治疗。术后病理诊断证实:65例乳头状瘤,8例乳头状瘤病,5例为导管内癌。乳管镜诊断符合率:乳头状瘤96%(65/68),乳头状瘤病100%(5/5),导管内癌100%(5/5)。单纯导管切除术65例,区段切除术8例,保乳根治术3例,改良根治术2例。结论通过光、针、色三位一体的方法定位以最小的切除范围达到最准确的切除目的,实现乳管内肿瘤的微创治疗。  相似文献   
9.
To assess the reproducibility and image quality of immediate postgadolinium chelate spoiled gradient-echo MRI in demonstrating disease of the abdominal aorta. All patients (27 patients: 21 men, 6 women) with substantial disease of the abdominal aorta, who underwent abdominal MR examinations at 1.5 T between 1991 and 1995, were entered in the study. Patients were referred for evaluation of suspected aortic disease (14 patients) or other abdominal diseases (13 patients). Three experienced investigators manually measured luminal and external aortic wall diameters and rated image quality, definition of inner and outer walls, extent of disease, and presence of other abdominal abnormalities, in an independent fashion. A cardiovascular surgeon then rated all studies to determine whether clinical management could be based on the MR findings alone. There was 98 to 99% agreement in measurements of luminal and external wall diameter between the three investigators. Overall image quality was rated as good in 77.8 to 88.9% of patients. A total of 31 additional nonaortic abdominal abnormalities were detected by all observers. The cardiovascular surgeon rated 25 of 27 studies as adequate to determine clinical management based on MR findings alone. Immediate postgadolinium spoiled gradient-echo MRI is a reproducible technique for the demonstration of abdominal aortic disease and possesses good image quality. Advantages of this technique include simultaneous evaluation of other nonvascular diseases of the abdomen, short examination time, and easy implementation as part of routine abdominal MRI scanning protocol.  相似文献   
10.
Percutaneous transluminal balloon angioplasty (PTA) was performed in 17 tibial arteries with an average cross-sectional area stenosis of 92% (range 75–99%) in 13 patients (14 limbs) for limb salvage. In 4 of 14 lower extremities, PTA of femoropopliteal arteries was also performed. Technical success with 50% or less residual stenosis was achieved in all 17 tibial vessels. At approximately 2 months after PTA, clinical improvement had occurred in 10 of 14 limbs; no patient was made worse. Most recent follow-up (mean 19 months, range 8–34 months) revealed continued satisfactory clinical success with no further vascular intervention in 9 of these 10 limbs (one patient died). Short segmental stenoses, residual stenoses less than 40% following PTA, and absence of diabetes or gangrene appear to be predictors of favorable clinical outcomes. Our results suggest that PTA of focal tibial stenosis is an effective and safe treatment modality in properly selected patients and that wider use of PTA may be justified.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号