全文获取类型
收费全文 | 9600篇 |
免费 | 933篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 82篇 |
儿科学 | 175篇 |
妇产科学 | 224篇 |
基础医学 | 1367篇 |
口腔科学 | 216篇 |
临床医学 | 1189篇 |
内科学 | 1848篇 |
皮肤病学 | 142篇 |
神经病学 | 1105篇 |
特种医学 | 402篇 |
外科学 | 1142篇 |
综合类 | 187篇 |
一般理论 | 2篇 |
预防医学 | 1082篇 |
眼科学 | 283篇 |
药学 | 619篇 |
中国医学 | 7篇 |
肿瘤学 | 467篇 |
出版年
2021年 | 152篇 |
2020年 | 98篇 |
2019年 | 155篇 |
2018年 | 156篇 |
2017年 | 140篇 |
2016年 | 132篇 |
2015年 | 155篇 |
2014年 | 223篇 |
2013年 | 370篇 |
2012年 | 534篇 |
2011年 | 492篇 |
2010年 | 267篇 |
2009年 | 255篇 |
2008年 | 448篇 |
2007年 | 462篇 |
2006年 | 451篇 |
2005年 | 398篇 |
2004年 | 425篇 |
2003年 | 347篇 |
2002年 | 410篇 |
2001年 | 275篇 |
2000年 | 219篇 |
1999年 | 215篇 |
1998年 | 119篇 |
1997年 | 101篇 |
1996年 | 115篇 |
1995年 | 103篇 |
1994年 | 88篇 |
1993年 | 77篇 |
1992年 | 228篇 |
1991年 | 196篇 |
1990年 | 196篇 |
1989年 | 205篇 |
1988年 | 192篇 |
1987年 | 166篇 |
1986年 | 151篇 |
1985年 | 173篇 |
1984年 | 150篇 |
1983年 | 129篇 |
1982年 | 84篇 |
1981年 | 70篇 |
1980年 | 76篇 |
1979年 | 112篇 |
1978年 | 92篇 |
1977年 | 82篇 |
1975年 | 71篇 |
1974年 | 87篇 |
1973年 | 79篇 |
1972年 | 71篇 |
1970年 | 69篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
Jasmine Poonian Nicola Walsham Thomas Kilner Elizabeth Bradbury Kristen Brooks Emma West 《Emergency medicine Australasia : EMA》2020,32(4):700-702
Emergency Medicine staff in Australia and New Zealand are at the forefront of the healthcare response to COVID‐19. This article describes a well‐being plan for ED staff that has been devised to mitigate against the negative psychological impact of the COVID‐19 pandemic. 相似文献
3.
4.
Bernard Natukunda Grace Ndeezi Lay See Er Francis Bajunirwe Gayle Teramura Meghan Delaney 《ISBT科学丛刊》2019,14(4):366-373
5.
6.
Fluid role boundaries: exploring the contribution of the advanced nurse practitioner to multi‐professional palliative care
下载免费PDF全文
![点击此处可从《Journal of clinical nursing》网站下载免费的PDF全文](/ch/ext_images/free.gif)
7.
Christine M Sapienza Michael P Cannito Thomas Murry Ryan Branski Gayle Woodson 《J. Speech Lang. Hear. Res.》2002,45(5):830-843
Acoustic analysis of a reading passage was used to identify the abnormal phonatory events associated with adductor spasmodic dysphonia (ADSD) pre- and postinjection of Botulinum Toxin A (Botox). Thirty-one patients (age 22 to 74 years) diagnosed with ADSD were included for study. All patients were new recipients of Botox, and the examination of their voice occurred before and after their initial injection of Botox. Acoustic events were identified from reading samples of the Rainbow Passage produced by each of the patients. These events were examined from sentences containing primarily voiced sound segments. Dependent variables included the number of phonatory breaks, frequency shifts, and aperiodic segments--all variables previously defined by the investigators. Additionally, calculated variables were made of the percentage of time these events occurred relative to the duration of the cumulative voiced segments. A sex- and age-matched control group (+/-2 years) was included for statistical comparison. Results indicated that those with ADSD produced more aberrant acoustic events than the controls. Aperiodicity was the predominant acoustic event produced during the reading, followed by frequency shifts and phonatory breaks. Within the ADSD group, the number of atypical acoustic events decreased following Botox injection. It is important that the occurrence of specific abnormal acoustic events was sufficient to differentiate the disordered speakers from the controls following as well as preceding initial Botox injection, as indicated by discriminant function analysis. This paper complements our previous work using this acoustic analysis method for defining the abnormal events present in the voice of those with ADSD and further suggests that these measures can be used in conjunction with perceptual impressions to differentiate speakers on the basis of initial severity. 相似文献
8.
Ann G Schwartz Geoffrey M Prysak Valerie Murphy Fulvio Lonardo Harvey Pass Jan Schwartz Sam Brooks 《Clinical cancer research》2005,11(20):7280-7287
PURPOSE: A role for estrogens in determining lung cancer risk and prognosis is suggested by reported sex differences in susceptibility and survival. Archival lung tissue was evaluated for the presence of nuclear estrogen receptor (ER)-alpha and ER-beta and the relationship between ER status, subject characteristics, and survival. EXPERIMENTAL DESIGN: Paraffin-embedded lung tumor samples were obtained from 214 women and 64 men from two population-based, case-control studies as were 10 normal lung autopsy samples from patients without cancer. Nuclear ER-alpha and ER-beta expression was determined by immunohistochemistry. Logistic regression was used to identify factors associated with ER positivity and Cox proportional hazards models were used to measure survival differences by ER status. RESULTS: Neither tumor (0 of 94) nor normal (0 of 10) lung tissue stained positive for ER-alpha. Nuclear ER-beta positivity was present in 61% of tumor tissue samples (170 of 278; 70.3% in men and 58.3% in women) and 20% of normal tissue samples (2 of 10; P = 0.01). In multivariate analyses, females were 46% less likely to have ER-beta-positive tumors than males (odds ratio, 0.54; 95% confidence interval, 0.27-1.08). This relationship was stronger and statistically significant in adenocarcinomas (odds ratio, 0.40; 95% confidence interval, 0.18-0.89). Women with ER-beta-positive tumors had a nonsignificant 73% (P = 0.1) increase in mortality, whereas men with ER-beta-positive tumors had a significant 55% (P = 0.04) reduction in mortality compared with those with ER-beta-negative tumors. CONCLUSIONS: This study suggests differential expression by sex and influence on survival in men of nuclear ER-beta in lung cancer, particularly in adenocarcinomas. 相似文献
9.
Jay P. Brooks 《Transfusion》2005,45(S4):159S-171S
Efforts to make blood transfusion as safe as possible have focused on making the blood in the bag as disease-free as possible. The results have been dramatic, and the costs have been correspondingly high. Although blood services will have to continue to deal with emerging pathogens, efforts to reduce the transfusion of infectious agents presently posing a risk will require high incremental costs and result in only improvements of a small magnitude.
The other aspect of safe blood transfusion, the actual transfusion process performed primarily in hospitals, has been accorded considerably less interest. We should turn our attention to enhancing overall blood safety by focusing on improving the process of blood transfusion. Errors involving patient, specimen, and blood product identification put transfused patients at risk, increasing the mortality risk for some. Solutions that could improve the transfusion process are discussed as a focus of this article. 相似文献
The other aspect of safe blood transfusion, the actual transfusion process performed primarily in hospitals, has been accorded considerably less interest. We should turn our attention to enhancing overall blood safety by focusing on improving the process of blood transfusion. Errors involving patient, specimen, and blood product identification put transfused patients at risk, increasing the mortality risk for some. Solutions that could improve the transfusion process are discussed as a focus of this article. 相似文献
10.
The influence of protein solubilisation, conformation and size on the burst release from poly(lactide-co-glycolide) microspheres. 总被引:5,自引:0,他引:5
Gayle Duncan Thomas J Jess Farahidah Mohamed Nicholas C Price Sharon M Kelly Christopher F van der Walle 《Journal of controlled release》2005,110(1):34-48
Encapsulation of proteins in poly(lactide-co-glycolide) microspheres via emulsion is known to cause insoluble protein aggregates. Following protein emulsification and encapsulation in PLGA microspheres, we used circular dichroism to show that the recoverable soluble protein fraction also suffers subtle conformational changes. For a panel of proteins selected on the basis of molecular size and structural class, conformational stability measured by chemical denaturation was not indicative of stability during emulsion-encapsulation. Partial loss of structure was observed for alpha-helical proteins released from freeze-dried microspheres in aqueous buffer, with dramatic loss of structure for a beta-sandwich protein. The addition of sucrose (a lyoprotectant) did not prevent the loss of protein conformation upon encapsulation. Therefore, the conformational changes seen for the released soluble protein fraction originates during emulsification rather than microsphere freeze-drying. Analysis of the burst release for all proteins in buffer containing denaturant or surfactant showed that the degree of protein solubilisation was the dominant factor in determining the initial rate and extent of release. Our data for protein release into increasing concentrations of denaturing buffer suggest that the emulsion-denatured protein fraction remains insoluble; this fraction may represent the protein loss encountered upon comparison of protein encapsulated versus protein released. 相似文献