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991.
为了能够精确地建立轻、中、重液压冲击分级脑损伤动物模型,我们设计了侧位液压冲击脑损伤装置。该装置由不锈钢储液管、压缩空气、减压设备及计算机等组成,可以精确地控制冲击气压的大小、记录冲击时脑组织所承受的压力、显示压力曲线、液压冲击后可以迅速释放系统内的压力,国内、外均未见报道。侧位液压冲击脑损伤随冲击压力的增加而加重,以冲击侧大脑半球为最重,也可波及对侧及脑底部。 相似文献
992.
目的:探讨急性心肌缺血再灌注早期不同时间心肌细胞内Fos蛋白表达的变化,为心肌早期缺血再灌注损伤致死死后诊断提供新方法。方法:在32只SD大鼠建立心肌早期缺血再灌注损伤模型,另外40只大鼠分为正常与缺血对照组。用免疫组化SABC法结合图象分析研究心肌细胞核Fos蛋白的累积情况。结果:缺血30min再灌注30min后,再灌注区有部分心肌细胞核呈弱阳性着色,以后随缺血时间延长核阳性增强。缺血90min再灌注30min后核棕褐色染色最强,180min后又开始减弱。正常和单纯缺血组心肌细胞核未见有阳性反应。HE染色无明显病理改变。结论:Fos蛋白表达高峰在缺血90~180min之间,FosSABC染色法可诊断缺血30min再灌注30min或更长时间的损伤。免疫组化染色法检测心肌细胞核Fos蛋白的表达有望成为急性心肌缺血再灌注死后诊断的一种有意义的手段。 相似文献
993.
缺血预处理对肝脏缺血再灌注损伤的保护作用 总被引:12,自引:0,他引:12
目的探讨缺血预处理对大鼠肝脏缺血再灌注损伤的保护作用。方法在大鼠肝脏持续60min缺血及30min再灌注之前,先进行5,10,15min的缺血及等长时间的再灌注。于再灌注30min完成时取标本测定肝功能、抗氧化酶、脂质过氧化物及形态学研究。结果持续60min缺血及30min再灌注后,肝功能明显受损,抗氧化酶活力显著下降,肝组织大片坏死;5min的缺血预处理能明显改善肝功能、提高抗氧化酶活力,减少肝细胞坏死;10min效果次之;15min反而加重肝脏损害。结论5min的缺血预处理对肝脏缺血再灌注损伤具有明显的保护作用,它可能为肝脏缺血再灌注损伤的防治提供一种简单有效的新方法 相似文献
994.
利用Marmarou氏脑损伤动物模型,测定大鼠脑损伤后不同时间和部位的丙二醛(MDA)含量。结果示:损伤后1h,额叶、顶叶、脑干等处的MDA水平分别比对照组高出367%,418%和351%(P<0.01),并持续增高,伤后4h达高峰后缓慢下降,伤后24h仍明显高于对照组。纹状体、颞叶等处伤后1h的MDA水平升高较上述部位稍低,而分别较对照组升高169%和133%(P<0.01),伤后4h虽仍持续升高,但不超过35%。提示在大鼠弥漫性脑损伤后短期内即有自由基生成,几乎波及脑内各个部位,但程度不一。 相似文献
995.
黄建安 《苏州大学学报(自然科学版)》1999,19(3):252
以猪油酸型急性肺损伤模型为实验对象,观察急性发病过程中心肺功能和肺实质的病理改变。结果表明:急性肺损伤对肺功能影响主要为肺静态顺应性、氧合指数、血氧分压和pH下降。气道峰压、吸气未平台压、气道阻力明显升高。分流量明显加大。血液动力学上表现为心输出量,氧运输下降,平均肺动脉压、肺血管阻力和全身血管阻力显著升高;右心房压、肺毛细血管模压和体循环动脉压基本不变;病理形态表现为典型的急性肺损伤。结果显示,本实验成功制成急性防损伤模型,并有显著的心肺功能不良改变。 相似文献
996.
Purpose. In a patient with internal derangement of the shoulder, the diagnostic method of choice is controversial. Conventional arthrography
can diagnose most rotator cuff tears accurately; however, in many institutions MR arthrography is usually necessary to diagnose
labral tears. We utilized decision tree methodology to compare the cost- effectiveness of conventional arthrography and conventional
MRI with a hypothetical algorithm in which a patient underwent arthrography, performed with admixed gadolinium, which if negative,
was followed by MRI.
Design. The use of double-contrast arthrography alone, conventional MRI alone, and gadolinium-enhanced MRI used as an adjunct to
conventional arthrography were modeled for the diagnosis of full-thickness rotator cuff tears (RCT), partial RCTs, labral
tears, and the absence of cuff/labral tears using decision analysis methodology. English language medical publications were
searched to determine the base probabilities for the accuracy of the diagnostic tests. The outcome utilities ranged from –1
to +1 to reflect the value of correct diagnostic evaluation. Charges for diagnostic tests and appropriate surgical treatments
were based on 1997 Medicare reimbursement rates for professional fees and hospital charges in an outpatient setting. Sensitivity
analyses were performed to evaluate the effects of uncertainty regarding the prevalence of each disease state and the accuracy
of several diagnostic tests.
Results. In the base-case analysis, the average effectiveness of double-contrast arthrography alone, MRI alone and arthrography selectively
followed by MRI were 0.6610, 0.6715, and 0.7204, respectively. The average costs for each of these strategies were $1090,
$2033, and $2339, respectively.
Conclusion. Arthrography performed with admixed diluted gadolinium, which if negative is immediately followed by MRI, was somewhat more
expensive than conventional MRI. However, because of much greater effectiveness, cost-effectiveness was significantly higher
for our proposed algorithm. Conventional arthrography without gadolinium, although less expensive, had severely limited effectiveness.
Received: 4 June 1999 Revision requested: 6 August 1999 Revision received: 30 August 1999 Accepted: 1 September 1999 相似文献
997.
Neuron-specific enolase as an effective immunohistochemical marker for injured axons after fatal brain injury 总被引:6,自引:0,他引:6
Recently, it has been reported that a diagnosis of diffuse axonal injury in cases with a short survival period can be made
with the use of immunolabelling for β-amyloid precursor protein (APP). We examined whether immunostaining for neuron-specific
enolase (NSE) can also be a useful marker for the detection of axonal injury in its early stages. Sections of the corpus callosum
from 19 cases of head injury and from 9 cases of no head injury were immunostained for NSE and stained by the standard Holmes’
silver method. For comparison, serial sections from several cases were immunostained for APP. Immunostaining for NSE as well
as for APP, labelled injured axons in head injury cases with as early as 1.5 h survival where Holmes’ staining failed to detect
any changes of axons. Since NSE and APP labelled only injured axons but not normal axons, the results were readily interpretable.
These findings indicate that NSE should be an effective marker for the detection of axonal injury in its early stages.
Received: 7 December 1998 / Received in revised form: 11 March 1999 相似文献
998.
The effect of supervised rehabilitation on strength, postural sway, position sense and re-injury risk after acute ankle ligament sprain 总被引:2,自引:0,他引:2
Holme E Magnusson SP Becher K Bieler T Aagaard P Kjaer M 《Scandinavian journal of medicine & science in sports》1999,9(2):104-109
The effect of an early rehabilitation program, including postural training, on ankle joint function after an ankle ligament sprain was investigated prospectively. Ninety-two subjects, matched for age, sex, and level of sports activity, were randomized to a control or training group. All subject received the same standard information regarding early ankle mobilization. In addition, the training group participated in supervised physical therapy rehabilitation (1 h, twice weekly) with emphasis on balance training. Postural sway, position sense and isometric ankle strength were measured 6 weeks and 4 months after the injury, and at 12 months re-injury data were obtained. In the training group, there was a significant difference between the injured and uninjured side for plantar flexion (P < 0.01), eversion (P < 0.01) and inversion (P < 0.05), but not for dorsiflexion at 6 weeks. In the control group, there was a significant difference between the injured and uninjured side for plantar flexion (P < 0.01), eversion (P < 0.01), inversion (P < 0.01), and dorsiflexion (P < 0.05) at 6 weeks. Postural sway, but not position sense, differed between the injured and uninjured side in both groups (P < 0.01) at 6 weeks. The side-to-side percent differences were similar in both groups for all variables (P > 0.05) at 6 weeks, and there were no side-to-side differences at 4 months in either group. In the control group, 11/38 (29%) suffered a re-injury, while this number was only 2/29 (7%) in the training group (P < 0.05). These data showed that an ankle injury resulted in reduced ankle strength and postural control at 6 weeks, but that these variables had normalized at 4 months, independent of the supervised rehabilitation. However, the findings also demonstrated that supervised rehabilitation may reduce the number of re-injuries, and therefore may play a role in injury prevention. 相似文献
999.
D. Blohm S. Kaalund B.W. Jakobsen 《Scandinavian journal of medicine & science in sports》1999,9(4):245-247
A case of an acute traction apophysitis, "little league elbow", in an adolescent badminton player is presented. After a period of intense badminton activity, the patient developed typical signs of inflammation related to his elbow. X-ray showed soft tissue calcifications and ultrasound showed intra-articular swelling and a possible apophysitis related to the elbow. After a period of immobilization followed by low activity he could return to normal sports activity. 相似文献
1000.
Pseudoaneurysm of the superficial femoral artery following accidental trauma: result of treatment by percutaneous stent-graft placement 总被引:4,自引:0,他引:4
Accidental trauma frequently involves the extremities, and can extend to involve their blood supply, causing exsanguinating
hemorrhage and pseudoaneurysm in the involved blood vessel. This is traditionally managed by surgical repair. We report a
case in which control of life-threatening hemorrhage and exclusion of a large, post-traumatic pseudoaneurysm in the superficial
femoral artery was performed by a commercially available stent-graft, without complication. This treatment method may be a
safe and effective alternative to surgery in selected patients.
Received: 10 February 1998; Revision received: 31 March 1998; Accepted: 20 April 1998 相似文献