全文获取类型
收费全文 | 53749篇 |
免费 | 3935篇 |
国内免费 | 1809篇 |
专业分类
耳鼻咽喉 | 670篇 |
儿科学 | 1248篇 |
妇产科学 | 754篇 |
基础医学 | 5702篇 |
口腔科学 | 768篇 |
临床医学 | 7114篇 |
内科学 | 9186篇 |
皮肤病学 | 1886篇 |
神经病学 | 3375篇 |
特种医学 | 2492篇 |
外国民族医学 | 1篇 |
外科学 | 2542篇 |
综合类 | 6722篇 |
现状与发展 | 5篇 |
预防医学 | 5788篇 |
眼科学 | 535篇 |
药学 | 6769篇 |
41篇 | |
中国医学 | 2550篇 |
肿瘤学 | 1345篇 |
出版年
2024年 | 116篇 |
2023年 | 752篇 |
2022年 | 1538篇 |
2021年 | 2172篇 |
2020年 | 1973篇 |
2019年 | 1724篇 |
2018年 | 1743篇 |
2017年 | 1798篇 |
2016年 | 1736篇 |
2015年 | 1794篇 |
2014年 | 3178篇 |
2013年 | 3858篇 |
2012年 | 3135篇 |
2011年 | 3241篇 |
2010年 | 2708篇 |
2009年 | 2461篇 |
2008年 | 2543篇 |
2007年 | 2572篇 |
2006年 | 2174篇 |
2005年 | 1973篇 |
2004年 | 1646篇 |
2003年 | 1488篇 |
2002年 | 1214篇 |
2001年 | 1172篇 |
2000年 | 1003篇 |
1999年 | 935篇 |
1998年 | 754篇 |
1997年 | 737篇 |
1996年 | 699篇 |
1995年 | 672篇 |
1994年 | 570篇 |
1993年 | 514篇 |
1992年 | 560篇 |
1991年 | 481篇 |
1990年 | 402篇 |
1989年 | 408篇 |
1988年 | 417篇 |
1987年 | 384篇 |
1986年 | 311篇 |
1985年 | 333篇 |
1984年 | 257篇 |
1983年 | 197篇 |
1982年 | 232篇 |
1981年 | 183篇 |
1980年 | 176篇 |
1979年 | 117篇 |
1978年 | 98篇 |
1977年 | 79篇 |
1976年 | 68篇 |
1975年 | 51篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
Food-dependent exercise-induced anaphylaxis in childhood 总被引:1,自引:0,他引:1
George Du Toit 《Pediatric allergy and immunology》2007,18(5):455-463
The clinical syndrome of food-dependent exercise-induced anaphylaxis (FDEIA) is typified by the onset of anaphylaxis during (or soon after) exercise which was preceded by the ingestion of the causal food allergen/s. In FDEIA, both the food allergen/s and exercise are independently tolerated. FDEIA is an uncommon allergic condition in childhood, but nonetheless is an important differential diagnosis to be considered when faced by a child who has experienced exercise-associated anaphylaxis. The diagnosis of FDEIA is heavily dependent on the clinical history. Allergy tests may need to be performed to a broad panel of food and food additives. Modified exercise challenges (performed with and without prior ingestion of food) are frequently required as allergy test results frequently return low-positive results. A diagnosis of FDEIA facilitates the safe independent return to exercise and reintroduction of foods for patients who otherwise may unnecessarily avoid exercise and/or restrict their diet. The natural history of FDEIA is unknown; however, a safe return is usually achieved when the ingestion of the causal food allergen/s and exercise are separated. 相似文献
62.
根据微动滑移振幅具有小位移的特点,设计制作了一种弓形传感装置,该装置能把小幅位移信号转换为电信号,并通过示波器实时显示出来,用这种测试装置来测量滑移式微动振幅具有测试方法简单而测试精度较高的优点。 相似文献
63.
平板运动试验阴性患者最大ST/HR斜率对冠心病的诊断价值 总被引:3,自引:1,他引:2
目的探讨平板运动试验阴性患者最大ST/HR斜率对冠心病的诊断价值.方法选择122例平板运动试验阴性而临床有明显冠心病指征的患者进行冠状动脉造影,测定其最大ST/HR斜率.结果平板运动试验阴性患者最大ST/HR斜率诊断冠心病的敏感性为68.2%,特异性为80.8%,准确性为76.2%;运动峰值心率<预计最大心率之85%组最大ST/HR斜率诊断冠心病的敏感性为92.8%,特异性为86.7%,准确性为89.7%,高于运动峰值心率≥预计最大心率之85%组.结论平板运动试验阴性患者最大ST/HR斜率对冠心病的临床诊断有较高的敏感性、特异性和准确性,尤其是对低运动水平的患者,对减少运动试验诊断的漏诊率具有重要意义. 相似文献
64.
通过对 5 0 0例经尿 11项试纸检查阴性的标本 ,沉渣镜检发现尚有 6 7例阳性 ,阳性率为 13.4 %。提示尿沉渣镜检 ,不失为泌尿系统疾病检查的必要手段不应忽视及偏废 相似文献
65.
Karen Moore Schaefer 《Rehabilitation nursing》2004,29(2):49-55
Fibromyalgia (FM) is a chronic, potentially disabling, cluster of symptoms that manifests as pain for 3 months or more and pain with pressure on 11 of 18 tender points throughout the body. Because there is no known cause, and therefore, no cure, treatment focuses on the control or relief of symptoms. Many patients are referred to rehabilitation settings for physical or exercise therapy. While exercise is helpful in the control of the pain, stiffness, fatigue, sleep disorders, and mood changes, a holistic approach to treatment is more effective. Rehabilitation nurses provide major support for patients with FM. Validation of the patients' experiences is essential for achieving quality of life. Many patients have a history of being undertreated because of a lack of credibility and invisibility of the illness. This article provides background information about FM, summarizes the FM trajectory, reviews approaches to management, and discusses the role of rehabilitation nurses in a holistic approach to care of clients with FM. 相似文献
66.
67.
目的探讨三康胶囊对高原人体运动后一氧化氮(NO)及其合酶(NOS)、乳酸(BLA)、血氨(Ammo)的影响.方法选择进驻海拔3 700 m高原1年的10名健康青年,口服三康胶囊15 d,在服药前后分别采用功量自行车进行渐增负荷运动,测定其血清 NO、NOS、BLA及Ammo含量.结果服药后较服药前运动后NO水平[(101.02±6.49) Vs (77.10±8.11)]和NOS活性[(71.40±7.23) Vs (56.29±6.28)]均增高, BLA[(7.58±0.79)Vs (6.13±0.74)]和Ammo[(80.11±9.44)Vs (69.38±8.86)]降低,有非常显著性差异(P<0.01).结论 三康胶囊能增强高原移居者运动后NOS活性,加速乳酸清除,减缓运动疲劳的发生. 相似文献
68.
目的探讨预适应锻炼对新兵急进高原后脑功能的改善作用。方法120名新兵随机分为4组:对照组、面罩组、运动组和面罩复合运动组。在进入高原前,面罩复合运动组佩带低氧呼吸器小步快走10 min,休息5 min后重复进行,上、下午各进行4次,连续进行7 d;面罩组、运动组分别只佩带低氧呼吸器或单纯运动。在空运进入高原后,比较进高原前、后的神经行为核心测试组合系统指标的改变,并对急性高原反应症状进行分析。结果使用低氧呼吸器复合小步快走5 min时动脉血氧饱和度可降到(80.5±5.7)%,达到预缺氧的目的。新兵进入3 658 m高原后,对照组、面罩组和运动组的数字跨度、目标追踪测试分值明显下降(P<0.05),而面罩复合运动组无明显改变(P>0.05);各组进藏前、后的简单反应时、数字译码和视觉保留均无显著性改变(P>0.05),手敏捷度则显著提高(P<0.05)。对照组、面罩组、运动组和面罩复合运动组的急性高原反应发病率分别为13.3%、20.0%、20.0%、3.3%。结论进入高原前,应用低氧呼吸器辅以适当运动,能改善急进高原人群的即时听觉记忆能力和手部运动的速度及准确性,避免部分脑功能的损害,并使急性高原反应发病率呈降低趋势。 相似文献
69.
A simulation study of three sequential methods for the comparison of two treatment groups when the response criterion is censored 总被引:1,自引:0,他引:1
Three recent sequential methods, group sequential analysis (GSA), the sequential probability ratio test (SPRT) and the triangular test (TT) are well suited to randomized clinical trials with a censored response criterion, as they do not require matched pairs of patients. We undertook a simulation study to investigate their statistical properties and to compare these three methods with the fixed-sample design. Our results suggest that the three methods have the expected statistical properties for size and power; they allow an important reduction of the average number of events before stopping, except with GSA when there is no treatment difference; the triangular test (closed design) appears the optimal design, as the variance of the number of events is smaller than with the sequential probability ratio test (open design) and analysis after every twenty new events does not alter the statistical properties of these sequential methods and enhances their usefulness. 相似文献
70.
Contact urticaria from protein hydrolysates in hair conditioners 总被引:1,自引:0,他引:1
Protein hydrolysates (PHs) are added to hair-care products (to "repair" broken hair), soaps, bath gels, creams, etc. From one to 22 PHs used in hair-care products (collagen, keratin, elastin, milk, wheat, almond, and silk) were tested in three patient groups: A) 11 hairdressers with hand dermatitis B) 2160 consecutive adults with suspected allergic respiratory disease subjected to routine skin prick tests C) 28 adults with atopic dermatitis.
In group A, all the 22 PHs were tested with scratch and patch tests. In groups B and C, one to three PHs were tested with prick tests. Positive scratch/prick test reactions were seen in 12 patients from three PHs altogether. All were women with atopic dermatitis, and all reacted to at least hydroxypropyl trimonium hydroly:ed collagen (Crotein Q"). In three patients, prick and open tests with a hair conditioner containing Crotein Q were performed with positive results. One patient reported contact urticaria on her hands, and two reported acute urticaria on their head, face, and upper body from a hair conditioner containing Crotein Q. In seven of the eight studied sera, specific IgE to Crotein Q was detected. In conclusion, PHs of hair cosmetics can cause contact urticaria, especially in patients with atopic dermatitis. 相似文献
In group A, all the 22 PHs were tested with scratch and patch tests. In groups B and C, one to three PHs were tested with prick tests. Positive scratch/prick test reactions were seen in 12 patients from three PHs altogether. All were women with atopic dermatitis, and all reacted to at least hydroxypropyl trimonium hydroly:ed collagen (Crotein Q"). In three patients, prick and open tests with a hair conditioner containing Crotein Q were performed with positive results. One patient reported contact urticaria on her hands, and two reported acute urticaria on their head, face, and upper body from a hair conditioner containing Crotein Q. In seven of the eight studied sera, specific IgE to Crotein Q was detected. In conclusion, PHs of hair cosmetics can cause contact urticaria, especially in patients with atopic dermatitis. 相似文献