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   64313篇
  免费   5822篇
  国内免费   857篇
耳鼻咽喉   281篇
儿科学   984篇
妇产科学   1856篇
基础医学   5014篇
口腔科学   447篇
临床医学   10830篇
内科学   3630篇
皮肤病学   288篇
神经病学   1944篇
特种医学   3811篇
外国民族医学   1篇
外科学   8514篇
综合类   8610篇
现状与发展   4篇
一般理论   5篇
预防医学   8449篇
眼科学   273篇
药学   3652篇
  288篇
中国医学   1370篇
肿瘤学   10741篇
  2024年   233篇
  2023年   1094篇
  2022年   2456篇
  2021年   3088篇
  2020年   3033篇
  2019年   2393篇
  2018年   2468篇
  2017年   2538篇
  2016年   2525篇
  2015年   2411篇
  2014年   5015篇
  2013年   5636篇
  2012年   4205篇
  2011年   4296篇
  2010年   3407篇
  2009年   3447篇
  2008年   3467篇
  2007年   3210篇
  2006年   2610篇
  2005年   2055篇
  2004年   1705篇
  2003年   1388篇
  2002年   1176篇
  2001年   1035篇
  2000年   901篇
  1999年   707篇
  1998年   635篇
  1997年   573篇
  1996年   441篇
  1995年   401篇
  1994年   345篇
  1993年   257篇
  1992年   255篇
  1991年   191篇
  1990年   151篇
  1989年   149篇
  1988年   121篇
  1987年   122篇
  1986年   82篇
  1985年   128篇
  1984年   119篇
  1983年   67篇
  1982年   76篇
  1981年   88篇
  1980年   75篇
  1979年   55篇
  1978年   39篇
  1977年   36篇
  1976年   23篇
  1975年   21篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
A prospective and controlled study of training after surgery for lumbar disc herniation (LDH). The objective was to determine the effect of early neuromuscular customized training after LDH surgery. No consensus exists on the type and timing of physical rehabilitation after LDH surgery. Patients aged 15–50 years, disc prolapse at L4–L5 or L5–S1. Before surgery, at 6 weeks, 4, and 12 months postoperatively, the following evaluations were performed: low back pain and leg pain estimated on a visual analog scale, disability according to the Roland–Morris questionnaire (RMQ) and disability rating index (DRI). Clinical examination, including the SLR test, was performed using a single blind method. Consumption of analgesics was registered. Twenty-five patients started neuromuscular customized training 2 weeks after surgery (early training group=ETG). Thirty-one patients formed a control group (CG) and started traditional training after 6 weeks. There was no significant difference in pain and disability between the two training groups before surgery. Median preoperative leg pain was 63 mm in ETG and 70 mm in the CG. Preoperative median disability according to RMQ was 14 in the ETG and 14.5 in the CG. Disability according to DRI (33/56 patients) was 5.3 in the ETG vs. 4.6 in the CG. At 6 weeks, 4 months, and 12 months, pain was significantly reduced in both groups, to the same extent. Disability scores were lower in the ETG at all follow-ups, and after 12 months, the difference was significant (RMQ P=.034, DRI P=.015). The results of the present study show early neuromuscular customized training to have a superior effect on disability, with a significant difference compared to traditional training at a follow-up 12 months after surgery. No adverse effects of the early training were seen. A prospective, randomized study with a larger patient sample is warranted to ultimately demonstrate that early training as described is beneficial for patients undergoing LDH surgery.  相似文献   
122.
The primary purpose of this study was to apply an occupational therapy programme for social skills training based on a cognitive-behavioural frame of reference to individuals with long-term mental illness. The goal of the social skills training group was to enable patients to develop verbal and non-verbal communication skills that could be generalised to everyday interpersonal encounters. A case example of the application of social skills training with a 38-year-old single male with a diagnosis of paranoid schizophrenia is described. The Group-Interaction Skills Survey developed by the author served as an outcome measure. Qualitative data confirmed the researcher's hypothesis that individuals with long-term mental illness can benefit from social skills training using a combination of role-playing, sociodrama, videotape recordings and creative media. Copyright © 1996 Whurr Publishers Ltd.  相似文献   
123.
We studied the effects of cardiac rehabilitation on the sympathovagalcontrol of heart rate variability in 30 patients after a first,uncomplicated myocardial infarction. Twenty-two patients completed8 weeks of endurance training (trained), while eight decidednot to engage in the rehabilitation programme for logisticalreasons, and were taken as untrained controls. Age, site ofinfarction, ejection fraction, ventricular diameter and stresstest duration were similar in the two groups at baseline. Heartrate variability was evaluated 4 weeks after infarction beforestarting rehabilitation, and repeated 8 weeks and one year laterin both trained and untrained patients. Measures of heart ratevariability, obtained from both time- and frequency- domainanalysis of a 15 min ECG recording in resting conditions, wereas follows: mean RR interval and its standard deviation (RRSD),the mean square successive differences (MSSD), the percent ofRR intervals differing >50 ms from the preceding RR (pNTN50),the low and high frequency components of the autoregressivepower spectrum of the RR intervals and their ratio (LF/HF).At baseline, heart rate variability was similar in trained anduntrained patients. In the short term (8 weeks after infarction),training increased RRSD by 25% (P<0·01), MSSD by 69%(P<0·01), pNN50 by 120% (P<0·01), and reducedLF/HF ratio by 30% (P<0·01). The effects persistedafter one year in trained patients. In untrained patients, theautonomic control of heart rate variability did not change 8weeks after myocardial infarction and was only slightly modifiedby time. Thus, exercise training, performed for 8 weeks aftera myocardial infarction, modifies the sympathovagal controlof heart rate variability toward a persistent increase in parasympathetictone, known to be associated with a better prognosis. This maypartly account for the favourable outcome of patients who undergorehabilitation.  相似文献   
124.
We report a case of metastatic lobular breast carcinoma with extrahepatic gastrointestinal disease. On the basis of clinical findings, radiologic investigations, computerized axial tomography, gastrointestinal endoscopy, and gastric biopsy, the diagnosis of gastric and ileal Crohn's disease was made. The correct diagnosis of peritoneal carcinomatosis was made at laparoscopy. This case exemplifies the utility of laparoscopy in establishing the diagnosis and staging for abdominal disease of uncertain etiology.  相似文献   
125.
Low‐income urban parents of color enrolled in a parent training study were interviewed to understand what motivated their participation and what led 30% of them to subsequently drop out. Most enrolled because they wanted to be better parents. Most dropped out because of time and schedule constraints. Retention was higher when parents' motivations for participation matched program goals. Program location and qualities of the recruiter were cited most often as important; financial compensation was cited least often as important.  相似文献   
126.
目的:研究不同孕期阶段(早、中、晚)孕妇凝血四项、血浆纤维蛋白(原)降解产物[plasma fibrin/fibrinogen degradation products, FDP]、D-二聚体的变化及临床意义,为临床诊疗提供理论支持。方法:回顾性分析2021年1月至2021年12月200例孕妇就诊资料中的凝血四项,纤维蛋白原(fibrinogen, FIB)、凝血酶原时间(prothrombin time, PT)、凝血酶时间(thrombin time, TT)、活化部分凝血活酶时间(activated partial thromboplastin time, APTT)。并对FDP与D-二聚体的检测结果进行统计分析,比较孕早期、中期、晚期三个阶段凝血四项、FDP和D-二聚体水平的变化。结果:孕早期、孕中期与孕晚期PT水平比较,差异有统计学意义(P<0.05);孕早期、孕中期与孕晚期三个阶段的TT相比,差异无统计学意义(P>0.05);孕早期的APTT明显长于中期、晚期孕妇,差异有统计学意义(P<0.05);孕早期、中期、晚期孕妇,随着孕周的增加,FIB水平逐渐升高...  相似文献   
127.
陈建新  田心宇  张键 《中国全科医学》2023,26(12):1485-1490
背景 肩关节内外旋肌肌力失衡会增加肩部运动损伤的风险,研究等速离心训练(IET)能否提高肌力平衡并改善神经肌肉控制能力具有重要的损伤预防意义。目的 探讨IET对健康青年人肩关节内外旋肌的肌力平衡及神经肌肉控制能力的影响。方法 2020年12月至2021年11月在复旦大学附属中山医院招募32例健康青年志愿者为研究对象,随机将其分为试验组(n=16)和对照组(n=16)。试验组接受4周IET,对照组接受4周连续被动运动训练(2次/周)。采用Biodex System 4 Pro多关节等速肌力测试与训练系统(美国Biodex公司)对两组研究对象的优势侧肩关节内、外旋肌群进行训练干预,分别在60(°)/s、120(°)/s速度下进行,干预前1周、干预结束后1周对两组肩关节内外旋肌的功能性比率(FR)、加速时间(AT)和达峰力矩时间(TPT)进行评估并比较。结果 试验组全部完成了4周的训练干预和评估,对照组2例中途退出。最终共30例研究对象数据纳入统计学分析。在60(°)/s和120(°)/s速度下,试验组干预后FR高于对照组(P<0.001),试验组干预后FR高于干预前(配对t检验:t<...  相似文献   
128.
目的:探讨玄胡索散抑制乳腺癌小鼠脾脏髓源抑制细胞(MDSC)分化的作用机制。方法:4~5周龄BALB/c雌性小鼠48只,其中6只为正常对照组,其他42只采用小鼠左侧第二对乳腺皮下脂肪垫接种4T1细胞构建乳腺癌荷瘤小鼠模型,分为粒细胞集落刺激因子(G-CSF)对照组、G-CSF敲减组、模型对照组、玄胡索散小剂量组、玄胡索散中剂量组、玄胡索散大剂量组和环磷酰胺组,每组6只。其中G-CSF对照组和G-CSF敲减组分别采用shRNA慢病毒转染联合嘌呤霉素构建相应4T1稳转细胞模型。各组造模48 h后,玄胡索散小剂量组、玄胡索散中剂量组、玄胡索散大剂量组分别按2、4、8 g·kg-1·d-1玄胡索散灌胃,每天一次;环磷酰胺组按30 mg/kg腹腔注射环磷酰胺,隔天一次;其他组给予等体积0.5%羟甲基纤维素纳。各组连续给药25 d。苏木精-伊红染色观察脾脏组织病理学改变,流式细胞术测定脾脏MDSC亚群比例,免疫荧光法检测脾脏CD11b、Ly6G共表达,酶联免疫吸附测定外周血G-CSF浓度。在体外,建立荷瘤小鼠脾脏与4T1稳转株共培养体系,玄胡索散(30μ...  相似文献   
129.
We previously reported the expression profiles of 9 cytochrome P450 isozymes (CYPs) proteins and those of 40 CYPs genes in pregnant rat's liver, placenta and fetal liver after treatment with pregnenolone-16alpha-carbonitrile (PCN) or phenobarbital (PB). This study was carried out focusing on the gene expression profiles of Phase II drug metabolizing enzymes, Glutathione S-transferase isozymes (GSTs) and UDP-glycosyltransferase isozymes (UDPGTs). Fischer 344 (F344) pregnant rats were daily treated intraperitoneally with 50 mg/kg of PCN or 80 mg/kg of PB from 13 to 16 days of gestation (DG). They were sacrificed on 17 DG, and microarray analysis using Affymetrix Rat Expression Array 230 A was performed. Among 16 GSTs genes examined in this study, 7 genes were significantly induced in dam's liver and 3 genes in fetal liver, respectively, in the PCN-group, while 8 genes were significantly induced in dam's liver and 1 gene in fetal liver, respectively, in the PB-group. On the other hand, among 11 UDPGTs genes examined, 5 genes were significantly induced in dam's liver and 3 genes in fetal liver, respectively, in the PCN-group, while 5 genes were significantly induced in dam's liver and 1 gene in fetal liver, respectively, in the PB-group. There were no significant changes in the placenta of all groups. This is the first report of the gene expression profiles of Phase II drug metabolizing enzymes in pregnant rat and fetal livers and placenta after treatment with typical inducers of drug metabolizing enzymes.  相似文献   
130.
The incidence of upper respiratory tract infections (URTI) and salivary immunoglobulin A concentrations [IgAs] of nine individuals were examined during 12 weeks of moderate exercise training, and compared to ten sedentary controls. Changes in maximal oxygen uptake were assessed at initial, mid-point and final evaluations (T1–3), while changes in [IgAs] and salivary immunoglobulin concentration-salivary albumin concentration ratio ([IgAs]:[Albs]) were monitored at T1 and T3. During the 12 week period, symptoms of URTI were self-recorded daily. During the period of training the level of fitness significantly increased (P<0.05) in the exercise group. The number of days recording symptoms of influenza, but not of cold, and total light URTI symptoms was significantly reduced in the exercise group during the last weeks of training. A significant increase in [IgAs] and in [IgAs]:[Albs] was found in the exercise group after training. Both [IgAs] and [IgAs]:[Albs] were significantly related to the number of days showing symptoms of influenza (P<0.01) and the total number of days of sickness (P<0.05). These data provide quantitative support for the belief that regular, moderate exercise results in an increased [IgAs] at rest and [IgAs]:[Albs], which may contribute to a decreased risk of infection. Electronic Publication  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