全文获取类型
收费全文 | 5573篇 |
免费 | 339篇 |
国内免费 | 26篇 |
专业分类
耳鼻咽喉 | 135篇 |
儿科学 | 89篇 |
妇产科学 | 115篇 |
基础医学 | 853篇 |
口腔科学 | 48篇 |
临床医学 | 494篇 |
内科学 | 1682篇 |
皮肤病学 | 40篇 |
神经病学 | 421篇 |
特种医学 | 124篇 |
外国民族医学 | 1篇 |
外科学 | 705篇 |
综合类 | 86篇 |
一般理论 | 6篇 |
预防医学 | 334篇 |
眼科学 | 56篇 |
药学 | 399篇 |
中国医学 | 19篇 |
肿瘤学 | 331篇 |
出版年
2023年 | 35篇 |
2022年 | 181篇 |
2021年 | 365篇 |
2020年 | 94篇 |
2019年 | 143篇 |
2018年 | 175篇 |
2017年 | 112篇 |
2016年 | 133篇 |
2015年 | 152篇 |
2014年 | 165篇 |
2013年 | 261篇 |
2012年 | 393篇 |
2011年 | 419篇 |
2010年 | 221篇 |
2009年 | 168篇 |
2008年 | 295篇 |
2007年 | 358篇 |
2006年 | 344篇 |
2005年 | 292篇 |
2004年 | 294篇 |
2003年 | 251篇 |
2002年 | 206篇 |
2001年 | 100篇 |
2000年 | 103篇 |
1999年 | 59篇 |
1998年 | 43篇 |
1997年 | 41篇 |
1996年 | 32篇 |
1995年 | 13篇 |
1994年 | 19篇 |
1993年 | 24篇 |
1992年 | 52篇 |
1991年 | 40篇 |
1990年 | 45篇 |
1989年 | 33篇 |
1988年 | 39篇 |
1987年 | 28篇 |
1986年 | 26篇 |
1985年 | 29篇 |
1984年 | 17篇 |
1983年 | 19篇 |
1982年 | 13篇 |
1981年 | 8篇 |
1980年 | 11篇 |
1979年 | 18篇 |
1978年 | 10篇 |
1976年 | 9篇 |
1975年 | 6篇 |
1974年 | 8篇 |
1970年 | 5篇 |
排序方式: 共有5938条查询结果,搜索用时 953 毫秒
1.
2.
3.
Ewelina Kazimierczyk Andrzej Eljaszewicz Paula Zembko Ewa Tarasiuk Malgorzata Rusak Agnieszka Kulczynska-Przybik Marta Lukaszewicz-Zajac Karol Kaminski Barbara Mroczko Maciej Szmitkowski Milena Dabrowska Bozena Sobkowicz Marcin Moniuszko Agnieszka Tycinska 《Pharmacological reports : PR》2019,71(1):73-81
Background
Acute myocardial infarction (AMI) causes irreversible myocardial damage and release of inflammatory mediators, including cytokines, chemokines and miRNAs. We aimed to investigate changes in the levels of cytokines (IL-6, TNF-α and IL-10), miRNAs profiles (miR-146 and miR-155) and distribution of different monocyte subsets (CD14++CD16-, CD14++CD16+, CD14+CD16++) in the acute and post-healing phases of AMI.Methods
In eighteen consecutive AMI patients (mean age 56.78?±?12.4 years, mean left ventricle ejection fraction – LVEF: 41.9?±?9.8%), treated invasively, monocyte subsets frequencies were evaluated (flow cytometry), cytokine concentrations were analyzed (ELISA) as well as plasma miRNAs were isolated twice – on admission and after 19.2?±?5.9 weeks of follow-up. Measurements were also performed among healthy volunteers.Results
AMI patients presented significantly decreased frequencies of classical cells in comparison to healthy controls (median 71.22% [IQR: 64.4–79.04] vs. 84.35% [IQR: 81.2–86.7], p?=?0.001) and higher percent of both intermediate and non-classical cells, yet without statistical significance (median 6.54% [IQR: 5.14–16.64] vs. 5.87% [IQR: 4.48–8.6], p?=?0.37 and median 5.99% [IQR: 3.39–11.5] vs. 5.26% [IQR: 3.62–6.2], p?=?0.42, respectively). In AMI patients both, analyzed plasma miRNA concentrations were higher than in healthy subjects (miR-146: median 5.48 [IQR: 2.4–11.27] vs. 1.84 [IQR: 0.87–2.53], p?=?0.003; miR-155: median 25.35 [IQR: 8.17–43.15] vs. 8.4 [IQR: 0.08–16.9], p?=?0.027, respectively), and returned back to the values found in the control group in follow-up. miR-155/miR-146 ratio correlated with the frequencies of classical monocytes (r=0.6, p?=?0.01) and miR-155 correlated positively with the concentration of inflammatory cytokines ? IL-6 and TNF-α.Conclusions
These results may suggest cooperation of both pro-inflammatory and anti-inflammatory signals in AMI in order to promote appropriate healing of the infarcted myocardium. 相似文献4.
Predictors of clustering of tuberculosis in Greater Vancouver: a molecular epidemiologic study 总被引:3,自引:0,他引:3
下载免费PDF全文
![点击此处可从《Canadian Medical Association journal》网站下载免费的PDF全文](/ch/ext_images/free.gif)
5.
Leslee J. Shaw Romalisa Miranda-Peats Piotr Slomka John Friedman Sean W. Hayes Daniel S. Berman Gary V. Heller Marcin Dada William E. Boden Paul Casperson Robert A. O’Rourke Ronald Schwartz William S. Weintraub David J. Maron Spencer King Koon Teo Pamela Hartigan 《Journal of nuclear cardiology》2006,13(5):685-698
Background Stress gated myocardial perfusion single photon emission computed tomography (gSPECT) is increasingly used before and after
intercurrent therapeutic intervention and is the basis for ongoing evaluation in the Department of Veterans Affairs clinical
outcomes utilizing revascularization and aggressive drug evaluation (COURAGE) trial.
Methods and Results The COURAGE trial is a North American multicenter randomized clinical trial that enrolled 2287 patients to aggressive medical
therapy vs percutaneous coronary intervention plus aggressive medical therapy. Three COURAGE nuclear substudies have been
designed. The goals of substudy 0 are to examine the diagnostic accuracy of the extent and severity of inducible ischemia
at baseline in COURAGE patients compared with patient symptoms and quantitative coronary angiography and to explore the relationship
between inducible ischemia and the benefit from revascularization when added to medical therapy. Substudy 1 will correlate
the extent and severity of provocative ischemia with the frequency, quality, and instability of recurrent symptoms in postcatheterization
patients. Substudy 2 (n _ 300) will examine the usefulness of sequential gSPECT monitoring 6 to 18 months after therapeutic
intervention. Together, these nuclear substudies will evaluate the role of gSPECT to determine the effectiveness of aggressive
risk-factor modifications, lifestyle interventions, and anti-ischemic medical therapies with or without revascularization
in reducing patients’ ischemic burdens.
Conclusions The unfolding of evidence on the application of gSPECT in trials such as COURAGE defines a new era for nuclear cardiology.
We hope the evidence that emerges from the COURAGE trial will further establish the role of nuclear imaging in the evidence-based
management of patients with stable coronary disease.
The COURAGE trial was supported by the Cooperative Studies Program of the Department of Veterans Affairs Office of Research
and Development in collaboration with the Canadian Institutes of Health Research. Unrestricted research grants were obtained
from Merck & Co; Pfizer Pharmaceuticals; Bristol-Myers Squibb Medical Imaging; Astellas Pharma; Kos Pharmaceuticals; Data
Scope; Astra Zeneca Pharmaceuticals; Astra-Zeneca-Canada; Schering-Plough Coorporation, Ltd; Sanofi-Aventis, Inc; First Horizon;
and GE Healthcare. All industrial funding for this trial was directed through the Department of Veterans Affairs. Additional
funding for this substudy was provided by grants to the Department of Veterans Affairs and Canadian Institutes of Health Research
from Astellas Pharma and Bristol-Myers-Squibb Medical Imaging. 相似文献
6.
Predicting outbreaks: a spatial risk assessment of West Nile virus in British Columbia 总被引:1,自引:0,他引:1
Kaoru Tachiiri Brian Klinkenberg Sunny Mak Jamil Kazmi 《International journal of health geographics》2006,5(1):21-21
Background
West Nile virus (WNv) has recently emerged as a health threat to the North American population. After the initial disease outbreak in New York City in 1999, WNv has spread widely and quickly across North America to every contiguous American state and Canadian province, with the exceptions of British Columbia (BC), Prince Edward Island and Newfoundland. In this study we develop models of mosquito population dynamics for Culex tarsalis and C. pipiens, and create a spatial risk assessment of WNv prior to its arrival in BC by creating a raster-based mosquito abundance model using basic geographic and temperature data. Among the parameters included in the model are spatial factors determined from the locations of BC Centre for Disease Control mosquito traps (e.g., distance of the trap from the closest wetland or lake), while other parameters were obtained from the literature. Factors not considered in the current assessment but which could influence the results are also discussed. 相似文献7.
J C Ho M Chan-Yeung S P Ho J C Mak M S Ip G C Ooi M P Wong K W Tsang W K Lam 《The European respiratory journal》2007,29(2):273-278
The present study aimed to determine the alterations of antioxidant activities in erythrocytes from patients with nonsmall cell lung carcinoma (NSCLC). A comparative study of the systemic antioxidant activities in red blood cell lysate from subjects with NSCLC and healthy control subjects was conducted. The antioxidants catalase, superoxide dismutase (SOD) and glutathione peroxidase (GPx) were measured using chemical kinetic reactions under spectrophotometry. In total, 189 cases of mostly advanced-stage IIIB or stage IV NSCLC and 202 healthy controls were studied. In subjects with lung cancer, there was similar catalase activity, lower SOD activity (median (interquartile range) 13.4 (9.0-27.2) versus 48.7 (27.0-64.3) U x (ghaemoglobulin(Hb)(-1)), and higher GPx activity (175.2 (126.6-288.3) versus 49.2 (39.5-59.2) mU x (gHb)(-1)) compared with controls. The antioxidant activities in lung cancer subjects were not associated with age, sex, smoking status, or tumour cell types. However, more advanced disease (stage IV compared with stage IIIB) was associated with lower SOD activity. Using multivariable analysis, the presence of lung cancer independently predicted SOD and GPx activities. In conclusion, nonsmall cell lung carcinoma in Chinese subjects is associated with alterations in systemic antioxidant activities, which may play an important role in carcinogenesis. 相似文献
8.
Piotr Podolec Grzegorz Kope? Jakub Podolec Piotr Wilko?ek Marek Krochin Pawe? Rubi? Marcin Cwynar Tomasz Grodzicki Krzysztof Zmudka Wies?awa Tracz 《Hypertension research》2007,30(12):1151-1158
The objectives of this study were to determine the relationship between carotid-femoral (cfPWV) and aortic pulse wave velocity (aPWV) and to compare their modulators and association with coronary artery disease (CAD). We studied 107 consecutive patients (68 men) with a mean age of 60.49+/-8.31 years who had stable angina and had been referred for coronary angiography. cfPWV and aPWV were measured simultaneously during cardiac catheterization using the Complior device and aortic pressure waveform recordings, respectively. Based on the presence or absence of significant coronary artery stenosis (CAS) patients were subdivided into a CAS+ or CAS- group. The mean values of cfPWV and aPWV were 10.65+/-2.29 m/s and 8.78+/-2.24 m/s, respectively. They were significantly higher in the CAS+ (n=71) compared with the CAS- (n=36) group and predicted significant CAS independently of cardiovascular risk factors and mean or systolic aortic blood pressure. aPWV and cfPWV were significantly correlated (r=0.70; p<0.001) but the degree of correlation differed significantly (p<0.03) between the CAS+ (r=0.74, p<0.001) and CAS- group (r=0.46, p=0.003). Age and mean aortic blood pressure were independent predictors for aPWV as well as cfPWV. In the receiver operating characteristic (ROC) analysis, aPWV and cfPWV had similar accuracy in identification of significant CAS (AUC [area under the ROC curve]=0.76 and 0.69, respectively; p=0.13). However, neither cfPWV nor aPWV was effective at differentiating the extent of CAD. In conclusion, aPWV and cfPWV are highly correlated parameters with similar determinants and comparable accuracy in predicting significant CAS. The strength of correlation between these two indices differed significantly between subjects with and those without CAS. 相似文献
9.
Marcin Wojnar Dariusz Wasilewski Halina Matsumoto Artur Cedro 《Alcoholism, clinical and experimental research》1997,21(8):1351-1355
A retrospective study compared the course of alcohol withdrawal, including delirium tremens, in women and men hospitalized in the Nowowiejski Hospital in Warsaw from 1973 to 1987. Medical records pertaining to 1179 patients were analyzed; 13.8% of these patients were women and 86.2% were men. The study showed that women began intensive alcohol drinking later than men ( p < 0.0001), but the period between the onset of alcohol abuse and the first occurrence of alcohol withdrawal was shorter in women than in men ( p < 0.0001). In the period of heavy drinking before hospitalization, women consumed significantly less alcohol then men ( p < 0.0001); moreover, women drank nonbeverage alcohol less frequently than men ( p < 0.05). Women were hospitalized substantially longer than men ( p < 0.0001), whereas the duration of alcohol withdrawal symptoms at the time of hospitalization was comparable in both groups. Withdrawal seizures were significantly more frequent among men than among women ( p < 0.001). Significant differences in the patients'somatic conditions were not noted between the groups, with the exception of anemia and decreased potassium concentration, which were more frequently observed in women (both p < 0.0001), and of increased concentration of ALT and hypoproteinemia, which were more frequent in men (respectively, p < 0.05 and p < 0.01). Co-existing personality disorders, depressive disorders, and anxiety disorders—as well as abuse of benzodiazepines and barbiturates—were more frequently observed in women ( p < 0.0001). The period between the first hospitalization due to alcohol withdrawal and the time of death was significantly shorter in men than in women ( p < 0.05). The results point to differences in the conditions and the course of alcohol dependence and alcohol withdrawal between women and men. 相似文献
10.
To Wong Betty Yuen-Ting Lau Ho-Leung Mak Man-Wah Pang Cecilia Cheon Shing-Kai Yip 《International urogynecology journal》2006,17(6):593-597
A territory-wide telephone survey was conducted in Hong Kong to assess the prevalence, knowledge, and treatment-seeking behaviour of Chinese women with urinary incontinence, using validated Chinese version of Urogenital Distress Inventory (UDI-6) and Incontinence Impact Questionnaire (IIQ-7). Women, 540, aged between 17 to 77 years were interviewed. Of the respondents, 40.8% reported stress urinary incontinence, 20.4% had urge incontinence and 15.9% had mixed incontinence. Among these, 16.0% reported quality of life impairment; 9.3% felt frustrated with low morale, and 15.2% had nervous and anxiety problems. However, as many as 78.3% of the respondents did not know that stress urinary incontinence is a disease entity, and 60.6% thought that leakage of urine was a normal aging process. For those respondents having stress urinary incontinence, the first treatment of choice was physiotherapy. The second choice was medication, and surgical treatment was the last option. Respondents with stress urinary incontinence showed higher education level. 相似文献