全文获取类型
收费全文 | 27831篇 |
免费 | 2875篇 |
国内免费 | 873篇 |
专业分类
耳鼻咽喉 | 302篇 |
儿科学 | 195篇 |
妇产科学 | 2109篇 |
基础医学 | 2700篇 |
口腔科学 | 519篇 |
临床医学 | 3143篇 |
内科学 | 999篇 |
皮肤病学 | 71篇 |
神经病学 | 1538篇 |
特种医学 | 1339篇 |
外国民族医学 | 24篇 |
外科学 | 5390篇 |
综合类 | 5116篇 |
现状与发展 | 9篇 |
预防医学 | 1432篇 |
眼科学 | 38篇 |
药学 | 1398篇 |
28篇 | |
中国医学 | 1258篇 |
肿瘤学 | 3971篇 |
出版年
2024年 | 72篇 |
2023年 | 432篇 |
2022年 | 707篇 |
2021年 | 1211篇 |
2020年 | 1102篇 |
2019年 | 886篇 |
2018年 | 895篇 |
2017年 | 1115篇 |
2016年 | 1233篇 |
2015年 | 1225篇 |
2014年 | 2339篇 |
2013年 | 2033篇 |
2012年 | 1830篇 |
2011年 | 2015篇 |
2010年 | 1625篇 |
2009年 | 1477篇 |
2008年 | 1351篇 |
2007年 | 1445篇 |
2006年 | 1280篇 |
2005年 | 991篇 |
2004年 | 859篇 |
2003年 | 773篇 |
2002年 | 606篇 |
2001年 | 556篇 |
2000年 | 408篇 |
1999年 | 357篇 |
1998年 | 317篇 |
1997年 | 308篇 |
1996年 | 279篇 |
1995年 | 229篇 |
1994年 | 218篇 |
1993年 | 174篇 |
1992年 | 150篇 |
1991年 | 121篇 |
1990年 | 106篇 |
1989年 | 102篇 |
1988年 | 96篇 |
1987年 | 78篇 |
1986年 | 85篇 |
1985年 | 95篇 |
1984年 | 75篇 |
1983年 | 58篇 |
1982年 | 76篇 |
1981年 | 47篇 |
1980年 | 37篇 |
1979年 | 29篇 |
1978年 | 24篇 |
1977年 | 17篇 |
1976年 | 13篇 |
1972年 | 6篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
111.
对50例神经根型颈椎病的CT征象进行了分析,并与X线平片加以比较。认为CT不仅在神经根型颈椎病的诊断中具有独特作用,而且在确定手术方法和手术途径的选择上也很有意义。作者认为在CT机还没有普及的情况下,摄一张良好的钩椎关节放大斜位片或椎间孔断层片对诊断神经根型颈椎病应是首选的。CT和X线平片相结合,综合分析,更有价值。 相似文献
112.
Anterior thoracic corpectomy without sternotomy: A strategy for malignant disease of the upper thoracic spine 总被引:9,自引:0,他引:9
SummaryBackground With increasing frequency, spine surgeons are being asked to provide decompression and stabilization in patients with spinal metastases. While no region of the spine is easily treated, the upper thoracic spine is perhaps the least accessible. Traditional approaches to this region involve either thoracotomy or at least limited sternotomy. The authors present an approach to anterior pathology of the upper thoracic spine that obviates the need for sternotomy.Methods Within the past two years, two patients with cervicothoracic metastases underwent anterior decompression and fusion without sternotomy. In both patients, the bodies of C7, T1, and T2 were removed. While both patients were prepared and draped for sternotomy, each required a neck dissection only. In both patients, left-sided incisions were made along the leading edge of the sternocleidomastoid. The platysma was divided with the overlying skin. With further dissection, the strap muscles were tagged and divided approximately one centimeter above their sternal attachments. The loose areolar tissue of the superior mediastinum was then bluntly dissected. Along the entire length of the incision, the vascular plane medial to the carotid sheath was developed to facilitate exposure of the anterior spine. A Farley-Thompson retractor system was then employed to retract and protect the superior mediastinal structures. With this exposure, corpectomies were carried out using a high speed drill. Fusion was accomplished through insertion of Steinmann pins into the adjacent intact bodies above and below. This was followed by application of methyl methacrylate. Both patients had immediate postoperative stability with preservation of spinal cord function. Both patients subsequently underwent removal of dorsally located tumor with posterior fusion.Conclusions The goal of cancer surgery is to provide for increased functional survival without undue morbidity. The authors feel that when possible, the pain of sternal and clavicular osteotomies should be avoided. The described approach works well in conjunction with a methyl methacrylate/Steinmann pin construct. Because of the intact sternum, the surgeon has a downward angle to access the superior endplate of T3. With adequate soft tissue dissection and retraction as described, however, T3 and perhaps even T4 are easily accessible. While this downward angle would likely not permit an anterior plating procedure, it lends itself nicely to Steinmann pin/methyl methacrylate fusion and spares the patient the pain and potential morbidity of sternotomy. 相似文献
113.
目的分析腰椎椎弓峡部裂的CT表现,探讨各个征象的诊断价值和意义.方法自可疑椎弓峡部裂脊椎的椎弓根的上缘至下一个椎弓根上缘,层厚2~3mm连续扫描.结果86例中发生L5椎弓峡部裂51例,L4者33例,L3,者2例.各种CT征象发现率为:环裂征91%,椎体前移征85%,双椎体征50%,椎管拉长征45%,双关节面征38%,葫芦征26%,游移征15%,磨旋征6%.结论环裂征是该病的特征性表现;双关节面征及葫芦征发现率较低,但特异性较高.椎管拉长征具有一定诊断价值,其它征象无论其发现率大小,均是该病的继发改变,不能作为确诊的直接依据. 相似文献
114.
宫腔镜电切术治疗宫颈肌瘤的临床应用 总被引:1,自引:0,他引:1
目的 :探讨应用宫腔镜电切术治疗宫颈肌瘤的临床应用价值。方法 :用宫腔镜电切术切除宫颈肌瘤3 7例 ,其中有蒂宫颈肌瘤 2 1例 ,无蒂内突型宫颈肌瘤 16例 ,术后随访 3~ 3 1个月。结果 :平均手术时间2 0 7min ,术中平均出血 2 0 5ml ,一次性治愈率达 10 0 % ,无 1例子宫穿孔、低钠血症、周围脏器损伤、感染及宫颈管粘连等并发症发生。结论 :治疗宫颈肌瘤首选宫腔镜电切术 ,它具有治愈率高、创伤小、恢复快、并发症少的特点。 相似文献
115.
M. Kneissel P. Roschger W. Steiner D. Schamall G. Kalchhauser A. Boyde M. Teschler-Nicola 《Calcified tissue international》1997,61(2):95-100
There is abundant data on cancellous bone in the aging human spine, but little relating to the growing vertebral cancellous
bone in childhood and adolescence. The purpose of this study was to map vertebral cancellous bone in a growth and age series
of historic skeletal samples and to make comparisons with data published on recent material. Lumbar vertebral bodies were
collected from 65 skeletons (0–60 years) from a medieval Nubian population. Ethnohistoric information was collected to interpret
conditions that might have influenced bone structure and metabolism. The cancellous bone was studied three dimensionally,
using stereophotography and scanning electron microscopy and morphometrically by performing a semiautomatic structural analysis
on digitized backscattered electron images of polymethacrylate-embedded material. The cancellous bone structure in the children
consisted mainly of a densely packed, uniform network of small rodlike trabeculae. The greatest bone volume fraction with
small, more platelike trabeculae was observed during adolescence. In young adults, larger platelike trabeculae were present
in the central zone and smaller trabeculae in the superior and inferior zones, as described for modern skeletal material.
Structural changes associated with aging were observed much sooner than in modern man. By the estimated age of approximately
50–60 years, the predominant architectural elements were slender rarified rods in both sexes. The ethnohistorical data suggest
that this was essentially a black African population of physically active peasants, not likely to suffer Vitamin D insufficiency
or deficient calcium intake. Thus an earlier onset of the biological age changes in cancellous bone found in modern populations
was probably prevalent.
Received: 1 March 1996 / Accepted: 31 December 1996 相似文献
116.
Ping Zhao 《中国结合医学杂志》1995,1(3):197-200
AStudyonExtension-FlexionDynamicLumbarSpineRadiographsinPatientswithLumbarIntervertebralDiscHerniationAStudyonExtension-Flexi... 相似文献
117.
目的:总结32例经椎弓根椎间融合与AF治疗胸腰椎骨折的经验。方法:应用经伤椎椎弓根椎体间融合并AF系统复位内固定,以提高复位效果与脊柱的稳定性。结果:全部病例获随访,时间3~23个月,伤椎均与上位椎体间融合,无矫正角度与高度丢失,无断钉及螺钉松动,神经功能平均1.5级以上的恢复。结论:经椎弓根椎间融合与AF治疗胸腰椎骨折,操作简单,复位可靠,可重建脊柱的稳定性,椎体间融合更符合生物力学内环境的持久稳定。 相似文献
118.
Epidemiology of abdominal symptoms in a random population: Prevalence,incidence, and natural history 总被引:8,自引:0,他引:8
Lise Kay Torben Jørgensen Kirsten Hougaard Jensen 《European journal of epidemiology》1994,10(5):559-566
The study presents results from a five-year follow-up on abdominal symptoms in an age and sex stratified random sample of 4,581 Danes. Abdominal pain occurred significantly more often among women (prevalence: 49%, incidence: 21%) compared to men (prevalence: 38%, incidence: 15%). Five years later the pain had disappeared in 43% of the men and 31% of the women (p=0.003). Distension, borborygmi, and altering consistency of stools occurred with a prevalence of approximately 50% and an incidence of approximately 30%, significantly more often among women compared to men. Five years later these symptoms had disappeared in about 20%. Prevalence of both heartburn and acid regurgitation were significantly higher among men (38%) than women (30%), whereas no sex difference was observed regarding incidence of these symptoms (16%). Approximately 30% of subjects who had experienced heartburn or acid regurgitation did not do so five years later. In conclusion, abdominal symptoms occur frequently and recurrently in the general population. This information is of importance to doctors when they evaluate patients with abdominal complaints, but no obvious organic etiology. 相似文献
119.
F. A. Calvo O. Abuchaibe I. Azinovic E. Tangco J. Aristu R. Martínez F. Pardo J. Alvarez-Cienfuegos J. M. Berián 《European radiology》1992,2(1):29-34
Thirty patients with malignant tumours in the upper abdomen underwent surgery and intraoperalive radiation (IORT), using electron beam, to: the surgical bed, residual or unresected tumour. The technical aspects and results of this treatment are described. Renal, adrenal, bile duct and gastrointestinal tumours were treated. along with several other lesions. The surgical procedure consisted in 10 cases simply of exposure of the tumour for IORT and in 20 the tumour was resected. The TORT dose ranged from 10 to: 20 Gv. In 13 patients, external beam radiation was also given to: residual tumour or to: areas of high risk for recurrence. Chemotherapy was given to: 10 patients. Tolerance to: the combined treatment was acceptable; with few complications related to: IORT.The median follow-up and survival time 23 months (range 4-more than 70 months). Local tumour control rate (or tumour stabilisation) is 90%. Distant metastases developed in 19 patients (63%). The actuarial survival rate for the group projected at 70 months (maximum follow-up) is 37%. IORT in useful in the management of tumours arising in the upper abdominal organs, for palliation surgery or when resectability of the tumour is in doubt. Indications for IORT include patients with uncommon tumours of the upper abdomen who are not be candidates for standardised cancer treatment.Presented at the European Congress of Radiology, Vienna, September 15–20,1991 相似文献
120.