全文获取类型
收费全文 | 32898篇 |
免费 | 1808篇 |
国内免费 | 574篇 |
专业分类
耳鼻咽喉 | 180篇 |
儿科学 | 118篇 |
妇产科学 | 53篇 |
基础医学 | 1733篇 |
口腔科学 | 3037篇 |
临床医学 | 2826篇 |
内科学 | 1318篇 |
皮肤病学 | 32篇 |
神经病学 | 420篇 |
特种医学 | 1917篇 |
外国民族医学 | 2篇 |
外科学 | 12812篇 |
综合类 | 5982篇 |
现状与发展 | 1篇 |
预防医学 | 1109篇 |
眼科学 | 200篇 |
药学 | 1940篇 |
62篇 | |
中国医学 | 1355篇 |
肿瘤学 | 183篇 |
出版年
2024年 | 117篇 |
2023年 | 546篇 |
2022年 | 1154篇 |
2021年 | 1483篇 |
2020年 | 1459篇 |
2019年 | 1332篇 |
2018年 | 1165篇 |
2017年 | 1079篇 |
2016年 | 1247篇 |
2015年 | 1134篇 |
2014年 | 2401篇 |
2013年 | 2292篇 |
2012年 | 2160篇 |
2011年 | 2379篇 |
2010年 | 1939篇 |
2009年 | 1808篇 |
2008年 | 1591篇 |
2007年 | 1627篇 |
2006年 | 1379篇 |
2005年 | 1330篇 |
2004年 | 1100篇 |
2003年 | 821篇 |
2002年 | 625篇 |
2001年 | 544篇 |
2000年 | 408篇 |
1999年 | 374篇 |
1998年 | 286篇 |
1997年 | 263篇 |
1996年 | 185篇 |
1995年 | 154篇 |
1994年 | 124篇 |
1993年 | 106篇 |
1992年 | 72篇 |
1991年 | 56篇 |
1990年 | 40篇 |
1989年 | 32篇 |
1988年 | 30篇 |
1987年 | 35篇 |
1986年 | 31篇 |
1985年 | 83篇 |
1984年 | 50篇 |
1983年 | 54篇 |
1982年 | 48篇 |
1981年 | 35篇 |
1980年 | 19篇 |
1979年 | 19篇 |
1978年 | 18篇 |
1977年 | 8篇 |
1976年 | 14篇 |
1975年 | 17篇 |
排序方式: 共有10000条查询结果,搜索用时 11 毫秒
61.
Generalized amyloidosis from β2-microglobulin,with caecal perforation after long-term haemodialysis 总被引:5,自引:0,他引:5
H. Zhou U. Pfeifer R. Linke 《Virchows Archiv : an international journal of pathology》1991,419(4):349-353
Summary A 73-year-old man with chronic renal failure of undetermined aetiology had received haemodialysis for 12 years when he died of acute purulent peritonitis due to caecal perforation. Amyloid deposits detected in a cystic bone lesion in the left hip had caused a pathological fracture 17 days before death. At autopsy, extensive amyloid deposits were found in the osteoarticular system, in the cartilaginous surface and the capsular tissue of joints, ligaments, vertebral discs and bone. In addition, vascular amyloid deposits were diagnosed in the heart, kidneys, testes, lungs, skin and in the gastrointestinal tract. A special feature of this case were interstitial amyloid deposits forming a fine-meshed structure in the myocardium and plate-like deposits in the gastrointestinal tract. Immunohistochemically, all these deposits reacted strongly with antibody to human
2-microglobulin but showed no reaction with antibodies to AA, Alambda, A-kappa and AF. The present case demonstrates that extra-osteoarticular manifestations of AB-amyloidosis can cause serious complications. 相似文献
62.
Astrocytic processes investing vascular structures or forming the surface of mammalian brain have large numbers of orthogonally packed aggregates of intramembrane particles, termed "assemblies." Similar particle aggregates are expressed by astrocytes derived from neonatal rat forebrain in secondary culture, but they are much more uniformly distributed across the membranes of the cultured cells. Dexamethasone, a potent glucocorticoid, affects the differentiation of astrocyte membrane structure in two patterns, depending on the rate of proliferation in the culture. When confluent secondary cultures of astrocytes are exposed to 5 microM dexamethasone, the densities of assemblies increase, and in some cells approach the values present in the glial limitans in vivo. However, when rapidly proliferating astrocytes are exposed to dexamethasone during the first week of secondary culture, most of the astrocytes fail to express any assemblies. The rate of astrocyte proliferation is slowed, and a lower cell density is reached during the first 2 weeks of secondary culture in dexamethasone. The suppression of assemblies is transient: as the cultures approach confluence, the proportion of cells expressing assemblies increases to nearly control levels, and the density of assemblies increases to greater than control values in some astrocytes. Certain of the effects of dexamethasone on cultured astrocytes may have relevance for understanding the mechanism(s) of its action in treating cerebral edema. 相似文献
63.
骨科下肢侧卧位手术牵引架的研制及临床应用 总被引:1,自引:0,他引:1
目的研制并临床验证一种简便、实用、灵活、科学的骨科下肢侧卧位手术牵引架.方法1999年1月~2003年1月采用本手术设备共进行了51例均在侧卧位状态下进行的手术;其中股骨粗隆间骨折23例、股骨粗隆下骨折4例,行DHS22例、Gamma钉5例;股骨中下段骨折24例,行股骨交锁钉3例、梅花钉3例、LCDCP18例.结果采用本手术设备的手术情况是DHS、Gamma钉组的平均手术时间为51±19min、出血量为100士57ml,交锁钉组的手术时间为70±19min、出血量为312±94ml;与常规的仰卧位手术比较P<0.01,同时方便C-臂X光机透视,尤其是侧位透视.此外,还可运用本手术设备进行股骨中下段骨折的其他各种内固定手术,牵引效能好,方便术区皮肤消毒及术中骨折复位.结论本骨科下肢侧卧位手术牵引架结构简单、零部件少、装卸容易、适应症广、操作方便、利于C-臂X光机透视,术中出血量少、损伤小、手术时间短,具有较好的实用型、先进性、科学性,值得临床推广应用. 相似文献
64.
The greyhound is a fatigue fracture model of a short distance running athlete. Greyhounds have a high incidence of central
(navicular) tarsal bone (CTB) fractures, which are not associated with overt trauma. We wished to determine whether these
fractures occur because of accumulation of fatigue microdamage. We hypothesized that bone from racing dogs would show site-specific
microdamage accumulation, causing predisposition to structural failure. We performed a fractographic examination of failure
surfaces from fractured bones using scanning electron microscopy and assessed microcracking observed at the failure surface
using a visual analog scale. Branching arrays of microcracks were seen in failure surfaces of CTB and adjacent tarsal bones,
suggestive of compressive fatigue failure. Branching arrays of microcracks were particularly prevalent in remodeled trabecular
bone that had become compact. CTB fractures showed increased microdamage when compared with other in vivo fractures (adjacent tarsal bone and long bone fractures), and ex vivo tarsal fractures induced by monotonic loading (P < 0.02). It was concluded that greyhound racing and training often results in CTB structural failure, because of accumulation
and coalescence of branching arrays of fatigue microcracks, the formation of which appears to be predisposed to adapted bone.
Received: 12 November 1999 / Accepted: 10 March 2000 相似文献
65.
钢的拉伸断口分维测定及应用 总被引:1,自引:0,他引:1
本文利用IBAS-2000全自动图像分析系统,运用Slit Island Analysis方法,对40号钢拉伸断口进行了实验室研究。结果表明,钢的热处理制度和拉伸试验温度对断口分维值有重要影响,室温拉伸断口分维数与延伸率呈幂函数关系。 相似文献
66.
螺旋CT三维重建在鼻骨骨折中的临床应用价值 总被引:9,自引:0,他引:9
目的:探讨螺旋CT三维成像对鼻骨骨折的诊断价值。方法:应用GE Lightspeed Plus多排螺旋机扫描仪,对46例鼻外伤患者进行鼻骨横断面扫描和三维重建成像,并对检查结果进行分析。结果:46例鼻外伤患者中,9例普通X线侧位平片未发现骨折(19.6%);CT图像均能清晰显示骨折线,其中单纯鼻骨骨折32例(69.6%),并发上颌骨额突骨折11例(23.9%),上颌窦骨折1例,筛窦纸样板骨折3例,鼻中隔断裂1例。结论:螺旋CT三维成像对于诊断鼻骨骨折具有重要的诊断价值。 相似文献
67.
儿童颅骨生长性骨折 总被引:1,自引:0,他引:1
目的 探讨儿童颅骨生长性骨折(Growing skull fractwre,GSF)的发病机制、诊治方法。方法 对我院1992年1月2002年4月10年间收治的6例GSF患儿的临床资料进行回顾行分析。结果 6例均有明确颅脑损伤病史,平均发病年龄2.99岁,头部包块、颅骨缺损及神经功能障碍等症状常见,颅骨平片见以骨折线为长轴的梭形颅骨缺损,CT检查显示包块为蛛网膜囊肿或脑膨出,术中见硬脑膜缺损大于颅骨缺损;Goldstein分型:Ⅰ型2例,Ⅱ型2例,Ⅲ型2例;GOS5分者3例(2例Ⅰ型和1例Ⅱ型),4分者2例(Ⅱ型和Ⅲ型各1例),3分者1例(Ⅲ型)。结论 ①颅骨骨折致硬脑膜破损为GSF发病的病理基础,婴幼儿期颅脑发育、外伤后局部颅内压力增高、骨折缘缺血为发病的重要因素;②GSF患儿颅骨缺损范围与病程不呈正相关,颅脑CT在GSF的诊断方面优于颅骨平片;③GSF一经确诊即应手术治疗,扩大开颅术能显露硬脑膜残缘,严密修补硬脑膜是手术成功的关键,Medepor材料适用于GSF患儿。Goldstein分型对指导预后有一定意义。 相似文献
68.
目的探讨髋臼骨折手术并发症发生原因及防治措施。方法我院对手术治疗的45例髋臼骨折中发生并发症的20例进行分析。结果本组总的并发症发生率为44.4%。其中肺栓塞1例,下肢深静脉血栓行成2例,医源性坐骨神经损伤1例,创伤性关节炎12例,异位骨化7例,股骨头缺血坏死5例。结论选择合适的手术入路,尽早手术,提高手术技巧和复位质量,术后正确有效的干预措施、合理的早期功能锻炼是防治髋臼骨折手术并发症的关键。 相似文献
69.
Helical CT in the primary trauma evaluation of the cervical spine: an evidence-based approach 总被引:10,自引:0,他引:10
This review provides a summary of the cost-effectiveness, clinical utility, performance, and interpretation of screening helical
cervical spine CT for trauma patients. Recent evidence supports the use of helical CT as a cost-effective method for screening
the cervical spine in high-risk trauma patients. Screening cervical spine CT can be performed at the time of head CT to lower
the cost of the evaluation, and when all short- and long-term costs are considered, CT may actually save money when compared
with traditional radiographic screening. In addition to having higher sensitivity and specificity for cervical spine injury,
CT screening also allows more rapid radiological clearance of the cervical spine than radiography. Patients who are involved
in high-energy trauma, who sustain head injury, or who have neurological deficits are candidates for CT screening. Screening
with CT may enhance detection of other potentially important injuries of the cervical region.
Received: 17 March Revision requested: 14 April 2000 Revision received: 19 July 2000 Accepted: 19 July 2000 相似文献
70.
补肾复活汤治疗48例老年股骨颈骨折的疗效观察 总被引:1,自引:0,他引:1
目的:探讨补肾复活汤对老年股骨骨颈骨折患者的治疗效果.方法:用补肾复活汤内服治疗老年股骨颈骨折48例,设对照组48例,通过1~6个月的治疗,观察治疗后骨折的愈合情况.结果:治疗组患者折愈合率达64.6%.结论:补肾复活汤有明显改善骨折端的血液循环,促进骨折愈合的作用. 相似文献