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51.
目的 计算肝细胞癌、肝转移瘤、肝脏海绵状血管瘤和肝囊肿的病灶/肝脏磁共振信号强度比(SIR),并评价其与病灶性质的关系。方法 随机选择经确诊的肝细胞癌、肝转移瘤、肝海绵状血管瘤和肝囊肿病例共92例(148个病灶)行前瞻性磁共振成像(0.5T)研究。计算4种病灶的SIR,并进行统计学分析。结果 在T1W图像上,肝海绵状血管瘤与恶性肿瘤的SIR值间差异无显著性(t=1.799,P=0.075);质子加权像上,良恶性肿瘤的SIR之间无统计学意义(t=0.691,P=0.491);T2WI上,良性病变的SIR显著高于恶性肿瘤(P<0.01),且4种病变的SIR值与回波时间(TE)之间均存在线性正向相关关系。结论 在T2WI个测得的SIR可用于区分肝脏占位性病灶的性质。  相似文献   
52.
BackgroundNon-union is a significant complication of fracture fixation surgery, and can negatively impact a patient’s quality of life. Low intensity pulsed ultrasound (LIPUS) has been used to treat delayed or non-unions previously in the literature. The aim of this study was to determine the success rate of LIPUS treatment in patients with chronic fracture non-unions, and to establish the effect of systemic or local factors on its success.MethodsThis was a retrospective, observational study which included all patients undergoing LIPUS treatment in a single institution. Patients deemed suitable for LIPUS underwent treatment for a period of 6 months from initiation. They were followed up with sequential radiographs to assess union at intervals of 6 weeks, 3 months, 6 months and 1 year. LIPUS treatment was considered to be successful when patients achieved clinical and radiological union, without the need for revision surgery.ResultsA total of 46 patients were included in the study; 8 were lost to follow – up, leaving 38 patients for the final analysis. The mean age of patients was 47.03 ± 19.7 with a male to female ratio of 1.2:1. Union was achieved in 57.89%; the rest underwent revision surgery. There was no significant association between outcomes after LIPUS treatment and patients’ age, gender, smoking status or type of non-union. Patients with a small inter-fragment bone gap were more likely to have a successful outcome after LIPUS (p = 0.041). Time to treatment did not have a statistically significant impact on outcomes after LIPUS. Interestingly, all 6 patients with diabetes in the study managed to achieve union after LIPUS.ConclusionsThis study demonstrates that LIPUS is not successful in a large proportion of patients with established fracture non-unions. However, it does represent a low risk treatment modality as an alternative to revision surgery, especially for patients with diabetes who have a small inter – fragment bone gap. More research in the form of large randomised controlled trials needs to be carried out to further assess the role of LIPUS in the treatment of non-unions.  相似文献   
53.
骨质疏松症是一种与年龄和性别有关的全身性疾病,表现特征为每单位体积的骨量减少,骨强度受损,患者容易骨折,造成生活质量降低。运动疗法相比药物疗法具有经济性、无不良反应等优势,被越来越多人所关注。然而运动疗法的疗效在实际应用过程中并没有完全凸显,主要受运动本身的特点(运动方式、运动强度)以及患者自身条件所影响。目前骨质疏松症的检测方式具有一定的不确定性,患者无法判断经过一段时间运动干预后的真正疗效,从而影响到运动参与的积极性,并且运动干预骨质疏松症的评价指标主要集中在骨密度和骨矿物质含量上,忽视了运动对于人体肌肉功能以及身体机能的影响。另外,骨质疏松症人群的机能状态存在很大差异,因此,想要达到较好的干预效果就需要根据患者特点制定最为合适的运动处方。目前,国内外对运动干预骨质疏松症存在的问题尚缺乏详细的概述,笔者就相关现存问题进行归纳总结,给出建议以供参考,旨在提高运动疗法干预骨质疏松症的效果。  相似文献   
54.
贺洋洋 《医疗装备》2021,(4):185-186
高强度聚焦超声(HIFU)是将超声的能量聚集在很小的区域内,通过高热量灼烧病变组织细胞,但不会对周围其他组织产生影响,因此,其被广泛应用于对肿瘤、大脑疾病和血管疾病的治疗中。现阶段,临床正尝试将磁共振引导的HIFU应用于神经外科手术治疗中,如治疗特发性震颤等。该研究简要回顾了HIFU的原理、设备和临床应用,叙述了其在肝脏、乳腺、前列腺、肾脏、子宫肿瘤治疗中的应用效果及应用前景。  相似文献   
55.
Videodensitometric analysis of myocardial contrast echocardiography is traditionally performed off line. Recently, an online contrast ultrasound analysis system, Acoustic Densitometry (Hewlett-Packard), was introduced. We compared pixel intensities acquired with Acoustic Densitometry to pixel intensities derived from videodensitometry. A tissue phantom was imaged in phase I using three transducer frequencies (2.5, 3.5, and 5.0 MHz). In phase II, an in vitro flowing tube model with various concentrations of Albunex® was imaged at two flow rates, 0.6 and 1.2 m/sec, and at two transducer frequencies, 2.5 and 3.5 MHz. The relationship between pixel intensities yielded by the two systems for identical ultrasound signals was determined with linear regression. Intensities derived with Acoustic Densitometry strongly correlated with those derived from the offline videodensitometry system. The intensities were related by a predictive multiplicative factor based on display characteristics of the two systems. These results suggest that semiquantitative, online perfusion analysis with Acoustic Densitometry is as sensitive as analysis offline with videodensitometry.  相似文献   
56.
We report our clinical experience with phototherapy in 3802 infants; 3629 were exposed to "standard" daylight phototherapy and 173 to "high-intensity" blue-light phototherapy. High-intensity blue-light phototherapy was twice as effective as standard daylight phototherapy in decreasing bilirubin concentrations. No failures occurred with high-intensity phototherapy compared with an overall failure rate of 1.84/1000 with daylight lamps; these cases were transferred to high-intensity phototherapy with prompt response. Rebound after cessation of phototherapy was greater in those exposed to high-intensity blue light with a significantly greater number requiring a second exposure. However, the incidence was still low. No third exposure was required in any infant. Nursing of infants under high-intensity blue light was more difficult and inconvenient as was clinical monitoring. The light also caused more stress on the nursing and medical personnel. However, the infants tolerated both types of phototherapy equally well. High-intensity blue-light phototherapy would seem to be the treatment of choice for infants with rapidly increasing or very high bilirubin levels, as well as in those not responding adequately to daylight phototherapy.  相似文献   
57.
目的:研究高强度聚焦超声(HIFU)治疗大肠癌肝转移病灶的安全性和有效性.方法:18例大肠癌术后肝转移患者31个病灶行HIFU治疗,观察患者生命体征、主要脏器功能、影像学检查(CT或MRI等)、并发症和肿瘤转归的情况.结果:所有患者生命体征平稳,肝、肾功能正常,平均随访16.1个月(6~38个月),失访2例,生存13例,12、18个月生存率分别为83.3%和66.7%,中位生存期16个月;随访25个病灶中,17个肿瘤块缩小超过50%,有5例出现新的转移灶,8例出现皮肤浅Ⅱ度烧伤.结论:HIFU治疗是一种安全、有效和非侵入性治疗大肠癌肝转移病灶的手段.  相似文献   
58.
高强度聚焦超声治疗肿瘤原理及应用原则   总被引:22,自引:0,他引:22  
潘春华  罗荣城 《中国肿瘤》2003,12(9):530-533
介绍高强度超声聚焦刀(HIFU)治疗肿瘤的原理、实验依据、治疗的特点、适应证和禁忌症、治疗原则等,认为HIFU与其他疗法结合将会在治疗肿瘤上有更大的突破.  相似文献   
59.
目的:探讨临床单用HIFU治疗局部晚期胰腺癌(local advanced pancreatic carcinoma,APC)的可能性。方法:4个中心共41例患者入选进行非随机病例对照研究,其中HIFU组24例,单用HIFU治疗;对照组17例,接受HIFU及吉西他滨综合治疗。比较两组的疗效、治疗费用及安全性,采用Cox回归分析进一步确定吉西他滨化疗对生存期的影响。结果:HIFU组临床受益率、平均生存期与对照组相似,分别为66.7%比76.5%(P=10.740)和141.5天比176.5天(P=0.3510);而治疗费用较低,为20500元比51805元(P=0.000);安全性更高。Cox回归分析显示仅体力状态、HIFU次数及临床受益进入方程(P=0.000),化疗对生存期无影响。结论:单用HIFU治疗APC,其疗效等同于HIFU和吉西他滨的综合治疗,但较综合治疗经济、安全。推测可以单独应用HIFU治疗局部晚期胰腺癌.值得临床进一步验证。  相似文献   
60.
放疗仪器是利用电离辐射对肿瘤进行治疗的装置;近距离放疗仪器是指将封装好的放射源经人体腔道放在肿瘤体附近或表面,或是将细针管插植于肿瘤体内导入射线源实施照射的放疗技术.通过改变射束剖面强度分布,达到形状适形和剂量适形,叫做调强适形放疗技术.  相似文献   
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