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   11131篇
  免费   835篇
  国内免费   292篇
耳鼻咽喉   123篇
儿科学   76篇
妇产科学   44篇
基础医学   1081篇
口腔科学   644篇
临床医学   923篇
内科学   1047篇
皮肤病学   47篇
神经病学   1290篇
特种医学   555篇
外国民族医学   2篇
外科学   2131篇
综合类   1279篇
现状与发展   1篇
预防医学   278篇
眼科学   2004篇
药学   353篇
  11篇
中国医学   163篇
肿瘤学   206篇
  2024年   43篇
  2023年   224篇
  2022年   368篇
  2021年   520篇
  2020年   508篇
  2019年   369篇
  2018年   423篇
  2017年   469篇
  2016年   351篇
  2015年   384篇
  2014年   718篇
  2013年   756篇
  2012年   631篇
  2011年   674篇
  2010年   541篇
  2009年   513篇
  2008年   528篇
  2007年   492篇
  2006年   440篇
  2005年   379篇
  2004年   260篇
  2003年   255篇
  2002年   220篇
  2001年   199篇
  2000年   165篇
  1999年   172篇
  1998年   147篇
  1997年   135篇
  1996年   130篇
  1995年   116篇
  1994年   102篇
  1993年   78篇
  1992年   84篇
  1991年   80篇
  1990年   68篇
  1989年   47篇
  1988年   53篇
  1987年   43篇
  1986年   68篇
  1985年   67篇
  1984年   94篇
  1983年   68篇
  1982年   68篇
  1981年   56篇
  1980年   45篇
  1979年   32篇
  1978年   33篇
  1977年   15篇
  1976年   11篇
  1975年   7篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Although the conventional outside-in technique is especially useful for repairing tears in the anterior portion of the meniscus, it has a disadvantage of making an additional 1–2 cm sized skin incision and tying knots subcutaneously over the capsule. Therefore we devised two all-inside repair techniques of lateral meniscus anterior horn tear according to the site of meniscal tear, meniscosynovial junction or red–red zone. Because these techniques are modified methods of the outside-in meniscal repair using a spinal needle, they are as simple as conventional outside-in technique. In addition they have advantages of vertical mattress suture, which is an important characteristic of the all-inside repair, and no additional incision. We recommend these techniques as an alternative method for repairing an anterior horn tear of the lateral meniscus.  相似文献   
52.
双极射频电热固缩治疗前交叉韧带松弛临床研究   总被引:5,自引:0,他引:5  
目的:对15例前交叉韧带双极射频电热固缩治疗进行回顾性研究,评估其临床疗效。方法:从2000年1月至2005年1月采用双极射频对16例前交叉韧带松弛的患者进行电热固缩治疗。完整随访者15例,男性11例,女性4例,平均年龄29岁。12例前交叉韧带部分损伤,3例为自体绳肌重建术后。电热射频设备输出功率为284W,组织内作用温度为65℃。术后患者采用支具制动,康复计划与前交叉韧带重建术后基本相同。结果:随访时间平均15·6个月(4~25个月)。Lysholm评分,术前74·27±5·51分(66~84分),术后3个月89·6±7·11分(72~99分),两者相比有显著性差异(P<0·01);术后最终评分83·33±11·81分(56~95分),虽仍显著高于术前评分(P<0·05),但与术后3个月比较有所降低。KT-1000测量结果,术前两侧胫骨前移差值为5·47mm±1·61mm(3·5mm~10mm),术后3个月为2·67mm±1·35mm(2~7mm),与术前测量值对比存在显著性差异(P<0·01);最终测量结果为3·8mm±1·96mm(2~9mm),虽仍显著低于术前测量值(P<0·05),但较术后3个月有所增加。所有患者均未出现明显的术后并发症。2例患者(13·3%)术后失效,接受了二期重建手术。结论:电热固缩治疗前交叉韧带松弛可获得较好的短期主、客观疗效,但长期随访疗效有所下降。建议慎重选择手术适应症。  相似文献   
53.
脊髓前动脉损伤致脊髓缺血性损伤模型的MRI评价   总被引:2,自引:0,他引:2       下载免费PDF全文
目的:研究经脊髓前动脉损伤,致脊髓缺血性损伤模型的高场强MRI信号表现特征。方法:选用12只家犬经颈前手术入路,切断脊髓前动脉,经高场强MRI扫描,对照病理分析脊髓前动脉损伤后脊髓的MRI信号变化特征。结果:脊髓前动脉损伤后脊髓MRI表现出异常T2WI高信号,且出现在脊髓前动脉损伤节段的前2/3,多表现为一例受累及或偏向一例。结论:MRI能确定脊髓缺血性损伤的部位及信号特征。  相似文献   
54.
Background. Partial harvesting of the left internal mammary artery (LIMA) is a widespread technique used during minimally invasive coronary operations performed through a left anterior small thoracotomy. The influence of persisting LIMA branches was investigated to evaluate their effect on the blood flow of the left anterior descending artery.

Methods. Thirty patients, 15 with totally (group A) and 15 with partially (group B) harvested LIMAs, were evaluated. All the patients underwent postoperative angiography, during which a flow map of the LIMA was performed. The average peak velocity and the diastolic-to-systolic peak velocity ratio were recorded. The LIMA graft flow pattern was recorded in the proximal and distal thirds of the artery. Intramammary adenosine (12 to 14 μg) was injected and the average peak velocities before and after injection were calculated.

Results. The average peak velocity was similar in both groups in the proximal and distal thirds of the LIMA (25 ± 7 and 26 ± 5 cm/sec, respectively, in group A versus 27 ± 5 and 25 ± 5 cm/sec, respectively in group B; p = NS). The diastolic-to-systolic peak velocity ratio was similar proximally (0.78 ± 0.3 in group A versus 0.69 ± 0.3 cm/s in group B; p = NS), but not distally (1.72 ± 0.1 in group A versus 0.97 ± 0.3 in group B; p < 0.0005). The LIMA graft flow reserve was similar both proximally and distally (2.6 ± 0.6 and 2.5 ± 0.3 cm/s, respectively, in group A versus 2.6 ± 0.5 and 2.6 ± 0.3 cm/s, respectively, in group B; p = NS).

Conclusions. The persistence of LIMA branches does not influence the blood flow of the left anterior descending artery after acute adenosine-induced myocardial hyperemia. If a left anterior small thoracotomy is used in left anterior descending artery direct revascularization, complete LIMA harvesting is not mandatory and depends on the personal preference of the surgeon.  相似文献   

55.
Summary The serratus anterior muscle in the rat is supplied by the serratus division of thoracodorsal vessels, in a pattern similar to man [2]. The serratus anterior muscles were transferred to the groin area as a free muscle flap in 17 rats and as a free muscle graft in 13 rats. In the free muscle flap group, the serratus anterior muscles of 8 of 10 rats survived; histological examination showed them to be viable and the vascular anastomoses were patent at the 30th day. In the free muscle graft group, all of the muscle grafts became necrotic. As a result, it is concluded that the microvascular transfer of serratus anterior muscles in rats is a useful small animal model for microsurgical laboratory training of clinical free flap transfers and also for performing pharmacological and biochemical studies in transplanted muscle.  相似文献   
56.
医用氧舱检验与安全   总被引:1,自引:1,他引:0  
本文介绍了医用氧舱的检验,医用氧舱的检验包括舱体、供排气、氧系统、电气系统等“硬件”设备的检验和设计、安装与使用管理的“软件”方面的检验。同时,针对检验过程中发现的影响医用氧舱安全使用的常见问题,本文进行了详细的讨论。  相似文献   
57.
In 268 of the 1,115 patients (24.0%) with gastric cancer who underwent a curative resection in our clinics, the tumor was located in the middle third of the stomach. The clinicopathological features and prognosis of these patients were divided into two groups, according to site of the tumor: anterior wall (n = 58) vs. other sites (n = 210). Clinicopathological factors did not differ between the two groups. The survival time for patients with a tumor in the anterior group was shorter than that for patients with a tumor in other areas (P < 0.05). The five-year survival rate was 79.3% for patients with an anterior tumor and 91.9% for those with a tumor at a different site. A multivariate analysis indicated lymph node metastasis, serosal invasion, and anterior wall location to be independent prognostic factors indicative of a poor prognosis when the tumor was located in the middle third of the stomach. For such patients, close follow-up is needed to detect possible recurrences. © 1993 Wiley-Liss, Inc.  相似文献   
58.
59.
At the Indiana University Medical Center, 99 patients with medically intractable complex partial seizures (MI-CPS) had presurgical evaluation with subsequent anterior temporal lobectomy. The majority of the patients had single photon emission tomography (SPECT) performed interictally as well as during an actual epileptic seizure (ictal scan). Decreased regional cerebral perfusion (rCP) was seen in 54/94 (57%) of the interictal scans corresponding to the eventual site of the surgery. However, ictal scans provided a higher yield; increased rCP in the temporal lobe during an actual seizure was observed in 60/82 (73%) concordant to the side of surgery. SPECT is a useful, noninvasive method of localizing the epilepti-form focus in patients with MI-CPS considered for resective surgery. Both interictal and ictal SPECT need to be performed; combined interictal hypo-perfusion and ictal hyperperfusion in the same focal area are unique to epileptogenic lesions. Ictal SPECT studies can be performed in the majority of patients during the period of continuous video/EEG monitoring with only a little additional effort. Combining the results of functional brain imaging (interictal and ictal SPECT, PET) with clinical semiology of seizures, surface and sphenoidal EEG, magnetic resonance imaging and other non-invasive tests, anterior temporal lobectomy can be recommended in approximately two-thirds of the patients without resorting to potentially dangerous intracranial EEG monitoring.  相似文献   
60.
Anorectal function was evaluated in eight patients who had low anterior resection of the rectum with a low anastomotic line, using an EEA stapler, with determination of function based on periodic manometric studies and clinical symptoms. Immediately following surgery all patients suffered from frequent bowel actions and soiling. These symptoms improved with time and most patients could enjoy almost normal daily life by the sixth postoperative month. One month after surgery, anal canal resting pressure and maximum squeeze pressure were significantly reduced and rectoanal inhibitory reflex was absent; neither showed a distinct tendency to improve thereafter. Rectal sensation and reservoir capacity, which also were seriously impaired, recovered satisfactorily by the time of the six-month examination. This suggests that an improvement of clinical symptoms following this operation is dependent upon the recovery of reservoir capacity and sensation of the neorectum, and that this operative procedure is a functionally acceptable option for low rectal cancer.  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