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   11337篇
  免费   1029篇
  国内免费   142篇
耳鼻咽喉   13篇
儿科学   64篇
妇产科学   60篇
基础医学   365篇
口腔科学   37篇
临床医学   475篇
内科学   5996篇
皮肤病学   11篇
神经病学   673篇
特种医学   89篇
外科学   163篇
综合类   329篇
预防医学   1064篇
眼科学   29篇
药学   2894篇
  1篇
中国医学   92篇
肿瘤学   153篇
  2023年   49篇
  2022年   95篇
  2021年   249篇
  2020年   341篇
  2019年   434篇
  2018年   412篇
  2017年   447篇
  2016年   479篇
  2015年   400篇
  2014年   743篇
  2013年   1362篇
  2012年   572篇
  2011年   652篇
  2010年   549篇
  2009年   594篇
  2008年   596篇
  2007年   531篇
  2006年   427篇
  2005年   246篇
  2004年   302篇
  2003年   297篇
  2002年   250篇
  2001年   227篇
  2000年   214篇
  1999年   199篇
  1998年   219篇
  1997年   164篇
  1996年   187篇
  1995年   154篇
  1994年   127篇
  1993年   150篇
  1992年   117篇
  1991年   78篇
  1990年   52篇
  1989年   26篇
  1988年   43篇
  1987年   33篇
  1986年   27篇
  1985年   98篇
  1984年   70篇
  1983年   35篇
  1982年   29篇
  1981年   35篇
  1980年   30篇
  1979年   24篇
  1978年   28篇
  1977年   19篇
  1976年   23篇
  1975年   16篇
  1974年   19篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
This article examines public opinion in US alcohol policies during the 1990s and their correlates in 2000, using five national telephone surveys. Trend analyses of public opinion on 11 common alcohol policies is presented and factor‐based policy scales, based on 14 items in 2000, are used to examine demographic correlates of support for various policy areas, using bivariate, linear (OLS) and logistic regression analyses. With the exception of the alcohol warning label policy, national support for alcohol policies declined (eight policies) or was unchanged in the 1990s for 11 measured policies. In 2000, four meaningful policy opinion factors were found with adequate reliabilities (αs 0.65–0.75) for three of four derived scales. In 2000, support for specific policies varies. Warnings on labels and advertisements have highest support (>90%), then interventions like prevention, treatment, and responsible beverage service at 70% (with similar levels seen for improving access to treatment). Alcohol controls show varied, but lower support from 25% (raising minimum drinking age further), to above 60% for banning sales in corner stores; only about a third favor higher alcohol taxes (35%) and more restrictive hours of sale (32%). In general, women and those with lower socio‐economic status show higher alcohol policy support. Multivariate results show heavier drinkers are least supportive of alcohol policy, while ethnic minorities, especially Hispanics are more favorable to alcohol controls and raising alcohol taxes. Since evidence‐based alcohol control policies show mixed, but lower public support than treatment, prevention and consumer warnings, there is a need for community‐based strategies to increase awareness of environmentally orientated alcohol policies and their public health benefits.  相似文献   
42.
《Journal of substance use》2013,18(3):225-228
Abstract

Background: Drinking motives are thought to be important mediators of the relationship between social anxiety and alcohol use. This project evaluates whether specific drinking motives accurately reflect alcohol dependence. If so, brief questions about drinking motives could serve as valuable alcohol screening tools with socially anxious patients.

Methods: This investigation was a secondary analysis of an existing data set of 83 subjects with social anxiety disorder and at-risk alcohol use. The relationship between Drinking Motives Questionnaire (DMQ-R-5) subscales and alcohol dependence was evaluated.

Results: Coping-Depression was the only subscale that contributed to the unique prediction of a diagnosis of alcohol dependence. Additionally, two items (i.e. “to cheer up when you’re in a bad mood” and “to forget painful memories”) predicted a diagnosis of alcohol dependence above and beyond their association with each other.

Conclusions: Among patients with social anxiety, two specific questions on the DMQ-R-5 could provide a useful screen for health professionals to predict alcohol dependence. It may be fruitful to specifically target the motives of “to cheer up when you’re in a bad mood” and “to forget painful memories” when providing advice during brief interventions.  相似文献   
43.
《Journal of substance use》2013,18(4):319-326
Abstract

Regional Alcohol Managers (RAMs) were employed in the nine English health regions over 2008–2011. Their mission was to impact on the ‘hard target’ of Alcohol-Related Hospital Admissions (AHRAs) through the ‘soft methods’ of persuasion and influence: working with local partners on evidence-based interventions. Drawing on a qualitative evaluation, this article shows how a central government policy imperative (ARHAs) led to ‘government at a distance’ responses, including the introduction of RAMs. The processes involved in shaping and delivering this function bore the hallmarks of a complex, interactive policy network model, involving individuals whose bearings and roles were flexible and sometimes ambiguous. While there were overlaps and blurring of boundaries, there were three levels of policy network: central government, regional and local. As the ‘network in the middle’, the RAMs were pulled in both directions by conflicting agendas but were also able to have an impact on central and local policy.  相似文献   
44.
饮酒对飞行人员红细胞变形性的影响   总被引:7,自引:0,他引:7  
目的探讨饮酒对飞行人员血液粘度和红细胞变形性的影响。方法35例飞行人员于6:00空腹抽静脉血进行血液流变学检测;于当日18:00吃饭时饮38度白酒100ml~150ml,于次日6:00空腹再次抽静脉血进行血液流变学检测,并与饮酒前的血液流变学结果进行自身对照。结果饮酒后次日晨全血高切粘度(200s-1)及红细胞刚性指数显著增高(P<0.05)。结论饮酒可使红细胞变形性显著降低,血粘度升高,导致脑及全身器官微循环灌注障碍,可能影响到飞行质量和安全  相似文献   
45.
The purpose of the study was to show whether it was possible to produce alcoholic cardiomyopathy by short-term alcohol ingestion combined with an infinitesimally low endotoxin injection. Wistar rats were fed an alcoholic liquid diet according to the formula of Lieber and Decarli, and challenged with an injection ofE. coli lipopolysaccharide (LPS) endotoxin (1.0 g/g body weight per day for ten weeks). After ten weeks alcohol diet combined with LPS challenge, light microscopical examination showed changes commonly seen in alcoholic cardiomyopathy such as hypertrophy, oedema and disarray of myofibers. By electron microscopy, degeneration of mitochondria and degeneration of myocardial fibers were observed, the latter showing disturbance of the myofibrilla arrangement and interstitial fibrosis. Rats on an alcoholic liquid diet and rats challenged with a single identical doses of LPS did not show characteristic histological findings of alcoholic cardiomyopathy. These results suggest that short-term alcohol ingestion combined with an infinitesimally low endotoxin injection experimentally produces alcoholic cardiomyopathy, and may support the idea that endotoxin plays an important role in the aetiology of alcoholic cardiomyopathy.  相似文献   
46.
目的为建立高空减压病易感性的筛选指标提供实验依据,我们观察了豚鼠口服酒精后高空减压时体内气泡生成的变化。方法30只豚鼠随机分成3组,其中两组分别在口服50%酒精溶液4.0和8.0ml后10.min和20min减压至13000m高度。用超声多普勒装置检测豚鼠心前区气泡音。结果口服8.0ml酒精溶液后减压,气泡生成明显增加(P<0.01),血浆表面张力明显降低(<0.01)。结论减压前饮酒能明显促进动物高空减压气泡的生成。  相似文献   
47.
Introduction: Given that little is known about the associations between alcohol use, cognition, and psychiatric symptoms among veterans with a history of mild traumatic brain injury (mTBI), we aimed to (a) characterize how they differ from veteran controls on a measure of problem drinking; (b) investigate whether problem drinking is associated with demographic or mTBI characteristics; and (c) examine the associations between alcohol use, mTBI history, psychiatric functioning, and cognition. Method: We assessed 59 veterans (n = 32 with mTBI history; n = 27 military controls) for problem alcohol use (Alcohol Use Disorders Identification Test: AUDIT), psychiatric symptoms, and neuropsychological functioning. Results: Compared to controls, veterans with mTBI history were more likely to score above the AUDIT cutoff score of 8 (p = .016), suggesting a higher rate of problem drinking. Participants with mTBI history also showed elevated psychiatric symptoms (ps < .001) and lower cognitive scores (ps < .05 to < .001). Veterans with higher AUDIT scores were younger (p = .05) and had less education (p < .01) and more psychiatric symptoms (ps < .01), but mTBI characteristics did not differ. After controlling for combat and mTBI history (R2 = .04, ns) and posttraumatic stress disorder (PTSD) symptoms (ΔR2 = .08, p = .05), we found that higher AUDIT scores were associated with poorer attention/processing speed, F(9, 37) = 2.55, p = .022; ΔR2 = .26, p = .03. Conclusions: This preliminary study suggested that veterans with mTBI history may be at increased risk for problem drinking. Problem alcohol use was primarily associated with more severe PTSD symptoms and poorer attention/processing speed, though not with combat or mTBI characteristics per se. Importantly, findings emphasize the importance of assessing for and treating problematic alcohol use and comorbid psychiatric symptoms among veterans, including those with a history of neurotrauma.  相似文献   
48.

Aim

To determine the extent to which ICD-10 alcohol intoxication codes are used for serious hospitalised injury and the distribution of these codes according to gender, age, injury mechanism and intent, severity of injury, and whether the patient was treated in an Intensive Care Unit.

Design

Cross-sectional study.

Setting

New Zealand.

Participants

All injury hospital discharges in 2010 that met specified severity criteria.

Measurements

Cases which had a measurement of BAC (Y90) coded, or only a subjective assessment of alcohol intoxication (F10.0).

Findings

2.5% had a blood alcohol recorded (Y90) and a further 3% were coded as being intoxicated but there was no blood alcohol code. All factors investigated were shown to be independently associated with the assignation of codes. Notable findings were the elevated odds of an alcohol code for males, assault and the more severe injuries.

Conclusions

Assessment of alcohol intoxication among seriously injured persons appears to be very uncommon. The development of a standardised instrument for clinical judgement of intoxication would be highly desirable.  相似文献   
49.
目的 探讨人口学因素和心理渴求对酒精依赖患者复发的影响。方法 采用前瞻性研究方法,选择2017年8月至2018年8月在3家精神专科医院招募符合《美国精神疾病诊断与统计手册》第4版(Diagnositic and Statistical Manual Disorder-Fourth Version, DSM-Ⅳ)酒精依赖诊断标准的住院治疗的男性患者158例,进行基线测查,并在基线后3个月进行随访,调查复饮情况。基线测查包括人口学资料、饮酒特征、临床机构酒精依赖戒断评估表(clinical institute withdrawal assessment-advanced revised, CIWA-Ar)、环境线索诱导及戒断期心理渴求视觉模拟标尺评分(visual analog scale,VAS)、密歇根酒精依赖筛查量表(Michigan alcoholism screening test, MAST)、焦虑自评量表(self-rating anxiety scale, SAS)、抑郁自评量表(self-rating depression scale, SDS)及饮酒促迫性量表(alcohol urge questionnaire, AUQ)。根据随访结果,将“复发”定义为在基线和随访之间任何时刻饮用含有乙醇的饮料,“复发时间”定义为首次饮酒距离基线的天数。是否复发和复发时间是主要结局指标,采用Cox比例风险回归模型分析影响酒精依赖复发的因素。结果酒精依赖患者3个月复发率为63.7%, 多因素Cox比例风险回归模型分析发现年龄(OR=0.975,P=0.030)及CIWA-Ar评分(OR=1.126,P=0.010)是影响酒精依赖复发的因素,两种环境下心理渴求与复饮差异无统计学意义(P > 0.05)。结论 年龄与住院期间酒精依赖戒断症状严重程度是酒精依赖复发的影响因素,其中年龄大是保护因素,戒断症状的严重程度重是危险因素,而线索诱导及戒断期心理渴求对酒精依赖患者复发的影响作用较小。  相似文献   
50.
Purpose We compared the clinicopathologic features affecting outcome after surgery for hepatocellular carcinoma (HCC) between patients with concurrent and previous chronic hepatitis B.Methods Group A consisted of 58 patients with concurrent chronic hepatitis B, defined by seropositivity for the hepatitis B surface antigen (HBsAg), and group B consisted of 18 patients whose HCC was detected after disappearance of the HBsAg. We assessed the influence of various characteristics on outcome.Results The mean age and percentage of patients suffering from alcohol abuse or diabetes mellitus were significantly greater in group B than in group A, whereas histologic hepatitis activity, hepatic fibrosis, and alanine aminotransferase activity were significantly lower in group B than in group A. The tumor-free survival rates were similar between the two groups, but the risk factors of recurrence differed. In group A, relative youth, high aspartate aminotransferase activity, low platelet count, multiple tumors, large tumor size, portal invasion, cirrhosis, nonanatomic resection, and positive surgical margin were risk factors. In group B, large tumor size and poor differentiation were risk factors.Conclusion Hepatitis B status, tumor factors, and the type of operation affected cancer recurrence after surgery for HCC in patients with concurrent chronic HBV, as opposed to only tumor factors in patients with previous chronic hepatitis B.  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