全文获取类型
收费全文 | 63651篇 |
免费 | 3902篇 |
国内免费 | 1629篇 |
专业分类
耳鼻咽喉 | 460篇 |
儿科学 | 986篇 |
妇产科学 | 903篇 |
基础医学 | 4390篇 |
口腔科学 | 732篇 |
临床医学 | 8473篇 |
内科学 | 15533篇 |
皮肤病学 | 268篇 |
神经病学 | 4313篇 |
特种医学 | 5465篇 |
外国民族医学 | 2篇 |
外科学 | 8588篇 |
综合类 | 9663篇 |
现状与发展 | 3篇 |
预防医学 | 1550篇 |
眼科学 | 2265篇 |
药学 | 3628篇 |
26篇 | |
中国医学 | 1267篇 |
肿瘤学 | 667篇 |
出版年
2024年 | 84篇 |
2023年 | 946篇 |
2022年 | 1678篇 |
2021年 | 2572篇 |
2020年 | 2303篇 |
2019年 | 2133篇 |
2018年 | 2143篇 |
2017年 | 1942篇 |
2016年 | 2054篇 |
2015年 | 2130篇 |
2014年 | 4460篇 |
2013年 | 4248篇 |
2012年 | 3617篇 |
2011年 | 3959篇 |
2010年 | 3325篇 |
2009年 | 3320篇 |
2008年 | 3404篇 |
2007年 | 3459篇 |
2006年 | 3117篇 |
2005年 | 2530篇 |
2004年 | 2034篇 |
2003年 | 1727篇 |
2002年 | 1445篇 |
2001年 | 1348篇 |
2000年 | 1012篇 |
1999年 | 920篇 |
1998年 | 903篇 |
1997年 | 844篇 |
1996年 | 653篇 |
1995年 | 637篇 |
1994年 | 542篇 |
1993年 | 493篇 |
1992年 | 444篇 |
1991年 | 354篇 |
1990年 | 303篇 |
1989年 | 265篇 |
1988年 | 255篇 |
1987年 | 221篇 |
1986年 | 185篇 |
1985年 | 214篇 |
1984年 | 182篇 |
1983年 | 101篇 |
1982年 | 150篇 |
1981年 | 109篇 |
1980年 | 103篇 |
1979年 | 84篇 |
1978年 | 71篇 |
1977年 | 45篇 |
1976年 | 42篇 |
1975年 | 22篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
121.
目的探讨瘤内注射或经支气管动脉灌注p53基因联合支气管动脉灌注化疗(BAI)治疗肺癌的安全性、疗效和给药途径。方法经病理证实的15例肺癌,首先在CT引导下经皮穿刺瘤内注射或经支气管动脉灌注p53基因(今又生~),2~5天后,行BAI灌注化疗药物;然后根据病情变化再次进行基因治疗和/或BAI。治疗后常规使用螺旋CT定期复查,评价治疗效果。结果全部15例患者均完成上述治疗,并接受随访2~11个月。有效率(CR+PR)46.7%(7/15),1例肺部肿块消失,6例肺部肿块缩小,3例纵隔淋巴结缩小,1例胸水减少,仅1例观察到肿瘤长大,14例临床症状有不同程度缓解93.3%(14/15)。p53治疗后6例出现发热(38℃~40℃),未观察到基因药物的其它严重副作用,无严重操作有关并发症出现。结论本研究结果初步显示,作为肿瘤综合治疗的一部分,p53基因治疗与BAI联合应用,是一种治疗肺癌安全、有效的方法,提高了BAI的治疗效果。经皮瘤内注射p53是否为一种较好的给药途径值得进一步探讨。 相似文献
122.
[目的]探讨吸烟对病人冠状动脉病变的影响。[方法]对吸烟组(5 0例)与不吸烟组(3 0例)进行冠状动脉造影,观察记录冠状动脉病变情况并进行统计学分析。[结果]两组冠状动脉病变记分、每日不同吸烟量与冠状动脉病变记分、不同的吸烟年限与冠状动脉病变记分比较均有统计学意义(P <0 .0 1)。[结论]长期吸烟可使冠状动脉病变程度加重,应加强对长期吸烟及冠状动脉介入术后病人的健康教育,有效预防和控制冠心病,提高人群的健康水平。 相似文献
123.
Secondary prevention of coronary events in coronary artery disease (CAD) patients with aspirin is generally accepted because of ease of administration, predictable safety, and proven efficacy. The use of long-term anticoagulant therapy with heparins, vitamin-K antagonists (VKAs), or thrombin inhibitors is, however, more controversial. During the last 40 years, several trials have been conducted in order to evaluate the role of anticoagulant therapy in patients with CAD as a protection against subsequent death and thrombo-embolic complications. The conducted trials are heterogeneous in many ways, concerning comparative medications, patient populations, endpoints and follow-up, which makes a standardized recommendation on the basis of these studies difficult. This review is an overview of the largest and best studies on this topic and discusses the scientific background for a possible use of VKA or an alternative anticoagulant treatment in CAD patients, looking at both the beneficial effects and the risk of bleeding. 相似文献
124.
Marcela Hernández Hoyos Piotr Orłowski Ewa Piątkowska-Janko Piotr Bogorodzki Maciej Orkisz 《International journal of computer assisted radiology and surgery》2006,1(1):51-61
The accuracy of 2D phase contrast (PC) magnetic resonance angiography (MRA) depends on the alignment between the vessels and
the imaging plane. PC MRA imaging of blood flow is challenging when the flow in several vessels is to be evaluated with one
acquisition. For this purpose, semi-automatic determination of the plane most perpendicular to several vessels is proposed
based on centerlines extracted from 3D MRA. Arterial centerlines are extracted from 3D MRA based on iterative estimation-prediction,
multi-scale analysis of image moments, and a second-order shape model. The optimal plane is determined by minimizing misalignment
between its normal vector and the centerlines’ tangent vectors. The method was evaluated on a phantom and on 35 patients,
by seeking the optimal plane for cerebral blood flow quantification simultaneously in internal carotids and vertebral arteries.
In the phantom, difference of orientation and of height between known and calculated planes was 1.2° and 2.5 mm, respectively.
In the patients, all but one centerline were correctly extracted and the misalignment of the plane was within 12° per artery.
Semi-automatic centerline extraction simplifies and automates determination of the plane orthogonal to one vessel, thereby
permitting automatic simultaneous minimization of the misalignment with several vessels in PC MRA. 相似文献
125.
S. A. R. Nouraei C. B. Singh M. S. Ferguson K. Young D. Roy J. M. Philpott 《European journal of plastic surgery》2007,30(4):153-157
The objective of this study is to assess the results of repairing septal perforations with a vascularized pedicled alar cartilage
island flap. Using the external rhinoplasty approach, a vascularized flap of alar cartilage, harvested as a cephalic trim
and pedicled on the ascending columellar branches of the superior labial artery was raised. Bilateral mucoperichondrial septal
flaps were elevated and the alar flap was transposed and secured within the defect and bilaterally overlaid with temporalis
fascia. Silastic sheets were placed and remained in situ until the grafts were revascularized from the peripheries of the
defect as well as centrally from the alar flap. The revascularized temporalis fascia acted as a scaffold for nasal remucosalization.
The alar flap also increased the long-term structural robustness of the repair. Between 1999 and 2003, 14 patients with septal
perforations ranging from 10 to 31 mm underwent septal reconstruction using this technique. There were nine males and five
females. The flap was successfully raised in all cases and long-term closure was maintained in 12 patients (86%). The alar
cartilage flap is an effective technique for repairing septal perforations in selected patients. It provides vascularized
tissue which nourishes the grafts during remucosalization, and a cartilaginous framework, which affords long-term structural
support to the repair. It also obviates the need to transpose nasal mucosa and create a secondary defect. The rhinoplasty
approach furthermore permits additional nasal deformities to be corrected at the same time.
Presented at the British Association of Plastic Surgeons Summer Scientific Meeting, Sheffield, UK (12 July 2006). 相似文献
126.
Yuji Takeda Naoki Minato Yuji Katayama Tomoki Shimokawa 《General thoracic and cardiovascular surgery》2005,53(1):42-45
Two successful cases of the surgical treatment for coronary artery aneurysm (non-Kawasaki disease) were reported. The first
case had a saccular aneurysm on the left circumflex coronary artery (LCx) #14. Resection of the LCx aneurysm was performed
subsequent to single vessel coronary artery bypass grafting (CABG) to the distal portion of LCx#14 under the cardioplegic
cardiac arrest. The second case had aneurysms on both the left anterior descending artery (LAD) #7 (fusiform) and the LCx#11
(saccular). After double vessel CABG to LAD#7 and LCx#11, ligation or resection of two aneurysms was performed successfully.
Postoperative courses have been uneventful with good angiographic results achieved. Since these surgical procedures demonstrated
safety, the patients are expected to achieve a good long-term prognosis. 相似文献
127.
小脑后下动脉动脉瘤的诊断和治疗 总被引:1,自引:0,他引:1
目的探讨小脑后下动脉动脉瘤的临床特征、诊断、鉴别诊断和治疗。方法回顾性分析12例小脑后下动脉瘤的临床表现、影像学特征、手术效果及诊治过程中存在的相关问题。结果12例中有11例因动脉瘤破裂出血而发病,单纯第四脑室出血4例,全脑室系统出血2例,小脑半球出血3例,小脑蚓部伴第四脑室出血1例,侧脑室伴第三脑室出血1例,以后颅窝占位病变表现1例。8例术前行DSA检查明确诊断,4例术中明确诊断。12例均行后颅窝开颅显微手术治疗,其中动脉瘤颈夹闭9例,孤立切除2例,动脉瘤加固术1例,术后2例因脑积水加重行脑室-腹腔分流术。12例中除1例术后留有轻偏瘫外,其余11例恢复良好。结论小脑后下动脉瘤多以第四脑室出血发病,少数以小脑半球或蚓部出血发病,及早治疗效果满意。手术方式应尽量夹闭动脉瘤颈,对于小脑后下动脉末端动脉瘤,可以采用孤立切除术。 相似文献
128.
股前外侧区穿支动脉的形态学研究及皮瓣设计 总被引:4,自引:2,他引:2
目的探讨以旋股外侧动脉降支为蒂的皮瓣设计方法,以便增加术前多普勒定位的准确性。方法6具动脉灌注明胶-氧化铅混悬液的新鲜成人整尸标本,解剖观测股前外侧区穿支,通过血管造影术和拍摄X线片测量其直径、行程、分支和定位。用3D—doctor和Scion Image软件分别测量穿支供血的趋向性、三维重建和单穿支供血面积。结果股前外侧区共有外径大于0.5mm穿支16支,平均外径0.8mm,平均供血面积45.61cm^2,其中20%为肌间隙穿支,80%为肌皮穿支。平均蒂长为(3.15±1.43)cm。自旋股外侧动脉降支发出的穿支在浅筋膜中的平均长度为2.63cm。结论改良的氧化铅-明胶灌注技术可以为皮动脉和穿支皮瓣的研究提供高质量的血管造影图像。本研究发现股前外侧单穿支皮瓣的最大供血面积是30cm×20cm。以股前外侧区穿支设计的穿支皮瓣可以移植到下肢或身体其他部位。 相似文献
129.
LIU Yixin FU Yan 《世界急危重病医学杂志》2005,2(6):990-991
【论文特点介绍】本研究观察了CRP是否可以作为肾动脉粥样硬化狭窄(ARAs)的独立危险因子。通过对危险因素进行多变量Logistic回归分析,结果表明年龄、冠脉病变严重程度、外周血管疾病是ARAS的独立危险因素,而CRP水平、高血压、高脂血症、肾功能不全并非ARAS的独立危险因素。 相似文献
130.
CT血管成像对肝细胞癌合并肝动脉-门静脉分流的诊断价值 总被引:4,自引:0,他引:4
目的探讨CT血管成像(CTA)对肝细胞癌(HCC)合并肝动脉-门静脉分流(APS)的诊断价值。方法127例HCC患者分别接受肝脏多层螺旋CT动态增强扫描和DSA检查,间隔时间3-15d。所有患者进行CTA检查,并以DSA为标准,对照分析CT动态增强扫描基础上进行CTA成像对APS的诊断价值。结果DSA证实52例(40.94%)HCC患者合并APS,中央型33例,周围型19例。CT横断面与横断面基础上结合CTA诊断APS的敏感度均为94.23%(49/52),特异度分别为84.00%(63/75)和97.33%(73/75),正确率分别为88.19%(112/127)和96.06%(122/127),阳性预测值分别为80.33%(49/61)和96.08%(49/51),阴性预测值分别为95.45%(63/66)和96.05%(73/76)。CTA排除了横断面CT对4例中央型APS和6例周围型APS的假阳性诊断。与DSA比较,多层螺旋CT对APS的分型符合率达88.46%(46/52),其中,中央型90.91%(30/33),周围型84.21%(16/19)。CTA还直观地显示23例重度分流中央型APS的供血动脉,其中19例为肝固有动脉分支,4例为胃十二指肠动脉分支。结论在多层螺旋CT动态增强扫描基础上进行CTA成像,能有效提高APS诊断的特异度和正确率。 相似文献