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   13339篇
  免费   1334篇
  国内免费   934篇
耳鼻咽喉   77篇
儿科学   157篇
妇产科学   99篇
基础医学   1528篇
口腔科学   199篇
临床医学   1645篇
内科学   1841篇
皮肤病学   155篇
神经病学   647篇
特种医学   454篇
外国民族医学   7篇
外科学   1386篇
综合类   2725篇
现状与发展   3篇
一般理论   1篇
预防医学   945篇
眼科学   260篇
药学   1501篇
  9篇
中国医学   880篇
肿瘤学   1088篇
  2024年   62篇
  2023年   210篇
  2022年   544篇
  2021年   647篇
  2020年   480篇
  2019年   496篇
  2018年   475篇
  2017年   407篇
  2016年   393篇
  2015年   534篇
  2014年   708篇
  2013年   685篇
  2012年   845篇
  2011年   935篇
  2010年   647篇
  2009年   491篇
  2008年   546篇
  2007年   636篇
  2006年   648篇
  2005年   593篇
  2004年   543篇
  2003年   712篇
  2002年   669篇
  2001年   552篇
  2000年   393篇
  1999年   359篇
  1998年   185篇
  1997年   190篇
  1996年   150篇
  1995年   139篇
  1994年   124篇
  1993年   93篇
  1992年   86篇
  1991年   85篇
  1990年   71篇
  1989年   59篇
  1988年   53篇
  1987年   45篇
  1986年   42篇
  1985年   24篇
  1984年   14篇
  1983年   6篇
  1982年   8篇
  1981年   4篇
  1980年   4篇
  1979年   10篇
  1978年   1篇
  1977年   1篇
  1968年   1篇
  1966年   2篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
71.
目的:了解社区精神分裂症患者的精神康复状况并分析相关影响因素。方法:应用自编问卷收集178例社区精神分裂症患者的精神康复相关资料,由精神科医生对患者评定社会功能缺陷筛选量表(SDSS)、临床大体印象量表(CGI)、简明精神病量表(BPRS)。结果:轻度精神残疾者为60.7%,中度及以上者为39.3%。患者的年龄、婚姻状况、首次发病年龄、病程、住院次数、治疗依从性、病情严重程度、精神症状及自知力与患者的社会功能恢复情况显著相关。结论:社区精神分裂症患者多数社会功能恢复较好,患者的社会人口学特征、治疗依从性和病情严重程度影响康复状况。  相似文献   
72.
This paper first applies the sequential cluster method to set up the classification standard of infectious disease incidence state based on the fact that there are many uncertainty characteristics in the incidence course.Then the paper presents a weighted Markov chain,a method which is used to predict the future incidence state.This method assumes the standardized self-coefficients as weights based on the special characteristics of infectious disease incidence being a dependent stochastic variable.It also analyzes the characteristics of infectious diseases incidence via the Markov chain Monte Carlo method to make the long-term benefit of decision optimal.Our method is successfully validated using existing incidents data of infectious diseases in Jiangsu Province.In summation,this paper proposes ways to improve the accuracy of the weighted Markov chain,specifically in the field of infection epidemiology.  相似文献   
73.
[目的]探讨脾气虚证大鼠血清胃泌素(gastrin,GAS)、胃窦黏膜胃泌素分泌细胞(G)的变化及黄芪建中汤的干预作用。[方法]以三因素复合的方法复制脾气虚证大鼠模型,随后分别以黄芪建中汤低、中、高剂量对脾气虚大鼠进行复健,在干预后不同时间段,分别检测血清木糖浓度、血清肌酸磷酸激酶活性、血清GAS水平及胃窦G细胞等指标。[结果]随用药时间的延长,各用药组上述指标逐步恢复;中、高剂量组用药21天时,与同期模型组比较,差异有显著性(P〈0.05或P〈0.01);其中,高剂量组对G细胞数的改善作用,优于中剂量组(P〈0.05)。[结论]脾气虚证胃窦G细胞数量减少,释放GAS减少,血清GAS水平降低;黄芪建中汤对脾气虚大鼠有可靠的治疗作用,中、高剂量均为有效用药浓度,尤以高剂量更为理想。  相似文献   
74.
The physiological homeostasis of the masticatory complex in short-faced patients is too robust to be disintegrated and reconstructed due to the powerful masseter muscle. This study innovatively introduced the botulinum toxin-A (BTX-A) into the field of dental occlusal treatment, providing a novel and minimally invasive therapy perspective for the two major clinical problems in these patients (low treatment efficiency and high rates of complications). In total, 10 adult patients with skeletal low angle seeking occlusal treatment (age: 27.0 ± 6.1 years; 4 males and 6 females) were administered 30–50 U of BTX-A in each masseter muscle and evaluated before and 3 months after injection based on cone-beam computed tomography (CBCT). We found a significant reduction in the thickness of the masseter muscle (MMT) (p < 0.0001). With regards to occlusion, we found a significant increase in the height of the maxillary second molar (U7-PP) (p < 0.05) with significantly flattened occlusal curves (the curve of Spee [COS] (p < 0.01), and the curve of Wilson [COW] (p < 0.05)). Furthermore, the variations in the temporomandibular joint exhibited a significant reduction in the anterior joint space (AJS) (p < 0.05) and superior joint space (SJS) (p < 0.05). In addition, the correlation analysis of the masticatory complex provided the basis for the following multiple regression equation: MMT = 10.08 − 0.11 COW + 2.73 AJS. The findings from our pilot study indicate that BTX-A, as a new adjuvant treatment attempt of occlusal therapy for short-faced patients, can provide a more favorable muscular environment for subsequent occlusal therapy through the adjustment of the biting force and may contribute to the reconstruction of healthier homeostasis of the masticatory complex. However, further research is required to establish the reliability and validity of these findings.  相似文献   
75.
目的观察立体定向适形放射治疗肺癌疗效和副反应。方法研究组采用立体定向适形放疗技术对40例Ⅰ-Ⅳ期肺癌病人进行治疗,单次靶区周边处方剂量2-6Gy,每周3-5次,总量60-72Gy;对照组采用常规放射治疗肺癌病人40例,DT1.8-2Gy/次,1次/天,总量60-70Gy;比较两组治疗后疗效、临床症状改善和不良反应。结果研究组治疗有效(CR PR)35例,占87.5%,其中CR8例占20%,PR27例占68%,临床症状改善率96.7%,放疗副反应发生率为13.5%;对照组:治疗有效(CR PR)31例,占77.5%,其中CR3例占7.5%,PR28例占70%,临床症状改善率为81.63%,放疗副反应发生率为25%。两组对比,研究组有效率高于对照组,但P>0.05无统计学意义。临床症状改善率研究组高于对照组,P<0.05,有统计学意义。放疗副反应发生率研究组明显低于对照组,P<0.001,有显著性差异。结论立体定向适形放射治疗肺癌有较好的近期疗效和症状改善率,与传统的常规放疗方法比较副反应明显减轻,患者易耐受,是一种有效、安全的治疗肺癌新的放疗方法。  相似文献   
76.
Background:To assess the benefits and harmful effects of Chinese herbal medicine (CHM) formulations in preventing anthracyclines (ANT)-induced cardiotoxicity.Method:The Cochrane Library, Pubmed and EMBASE databases were electronically searched for relevant randomized controlled trials (RCTs) published till December 2021 in English or Chinese-language, in addition to manual searches through the reference lists of the selected papers, and the Chinese Conference Papers Database. Data was extracted by 2 investigators independently.Result:Seventeen RCTs reporting 11 different CHMs were included in this meta-analysis. The use of CHM reduced the occurrence of clinical heart failure (RR 0.48, 95% CI 0.39 to 0.60, P < .01) compared to the control group. Data on subclinical heart failure in terms of LVEF values showed that CHM reduced the occurrence of subclinical heart failure (RR 0.47, 95% CI 0.35 to 0.62, P < .01) as well.Conclusion:CHM is an effective and safe cardioprotective intervention that can potentially prevent ANT-induced cardiotoxicity. However, due to the insufficient quality of the included trials, our results should be interpreted with cautious.  相似文献   
77.
Biomass materials are high-quality raw materials for the preparation of natural, green and highly active functional materials due to their rich active groups, wide sources and low toxicity. Bagasse xylan (BX) and resveratrol (Res) were used as raw materials to introduce ethylene glycol dimethacrylate (EGDMA) via grafting reaction to obtain the intermediate product BX/Res-g-EGDMA. The intermediate was esterified with 3-carboxyphenylboronic acid (3-CBA) to obtain the target product 3-CBA-BX/Res-g-EGDMA. The BX/Res-composite-modified nanoderivative with antitumor activity was synthesized with the nanoprecipitation method. The effects of the reaction conditions on the grafting rate (G) of BX/Res-g-EGDMA and the degree of substitution (DS) of 3-CBA-BX/Res-g-EGDMA were investigated using single-factor experiments. The results showed that under the optimized process conditions, G and DS reached 142.44% and 0.485, respectively. The product was characterized with FTIR, XRD, TG-FTC, 1H NMR and SEM, and its anticancer activity was simulated and tested. The results showed that 3-CBA-BX/Res-g-EGDMA had a spherical structure with an average particle size of about 100 nm and that its crystalline structure and thermal stability were different from those of the raw materials. In addition, 3-CBA-BX/Res-g-EGDMA showed the best docking activity with 2HE7 with a binding free energy of −6.3 kJ/mol. The inhibition rate of 3-CBA-BX/Res-g-EGDMA on MGC80-3 (gastric cancer cells) reached 36.71 ± 4.93%, which was 18 times higher than that of BX. Therefore, this material could be a potential candidate for biomedical applications.  相似文献   
78.
Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide; however, cases with metastasis to the oral cavity are extremely rare. Herein, we report a 68-year-old man who was diagnosed with HCC. Ten months after surgical removal of the right half of his liver, the patient developed gingival metastasis. Unfortunately, the patient died 4 months after the diagnosis. We discuss treatment options, pathological results, and disease prognosis. When a mandibular gingival mass is found, metastatic tumors should be considered in the differential diagnosis. In this regard, the patient’s medical history and physical examination are valuable indicators for the diagnosis of mandibular gingival metastasis. This case provides a basis for the clinical diagnosis of metastatic HCC involving the oral cavity.  相似文献   
79.
80.
目的 观察模拟失重对人下肢脂肪体积的影响,验证磁共振水脂分离成像技术在测量人下肢脂肪容积中的可行性.方法 14名男性健康志愿者,-6°头低位卧床30 d,使用磁共振水脂分离成像(Dixon)技术采集卧床前后的下肢横断面解剖图像,测量卧床前后下肢脂肪体积.结果 与卧床前相比,卧床后所有志愿者下肢总脂肪体积及大腿段脂肪体积显著增加(P<0.001);小腿段脂肪体积呈增加趋势,但无统计学差异(P>0.05).结论 使用MRI水脂分离成像可以清晰地显示卧床前后下肢脂肪体积的变化;-6°头低位卧床30 d后下肢脂肪体积明显增加.  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