全文获取类型
收费全文 | 1163篇 |
免费 | 74篇 |
国内免费 | 34篇 |
专业分类
耳鼻咽喉 | 12篇 |
儿科学 | 25篇 |
妇产科学 | 32篇 |
基础医学 | 172篇 |
口腔科学 | 18篇 |
临床医学 | 120篇 |
内科学 | 164篇 |
皮肤病学 | 10篇 |
神经病学 | 72篇 |
特种医学 | 181篇 |
外科学 | 104篇 |
综合类 | 32篇 |
一般理论 | 2篇 |
预防医学 | 129篇 |
眼科学 | 61篇 |
药学 | 48篇 |
中国医学 | 1篇 |
肿瘤学 | 88篇 |
出版年
2022年 | 4篇 |
2021年 | 14篇 |
2020年 | 4篇 |
2019年 | 10篇 |
2018年 | 20篇 |
2017年 | 11篇 |
2016年 | 16篇 |
2015年 | 29篇 |
2014年 | 45篇 |
2013年 | 44篇 |
2012年 | 63篇 |
2011年 | 57篇 |
2010年 | 38篇 |
2009年 | 59篇 |
2008年 | 44篇 |
2007年 | 69篇 |
2006年 | 77篇 |
2005年 | 53篇 |
2004年 | 37篇 |
2003年 | 26篇 |
2002年 | 30篇 |
2001年 | 39篇 |
2000年 | 20篇 |
1999年 | 29篇 |
1998年 | 35篇 |
1997年 | 37篇 |
1996年 | 23篇 |
1995年 | 17篇 |
1994年 | 18篇 |
1993年 | 18篇 |
1992年 | 20篇 |
1991年 | 20篇 |
1990年 | 18篇 |
1989年 | 29篇 |
1988年 | 26篇 |
1987年 | 17篇 |
1986年 | 26篇 |
1985年 | 20篇 |
1984年 | 8篇 |
1983年 | 5篇 |
1981年 | 10篇 |
1980年 | 3篇 |
1979年 | 9篇 |
1978年 | 10篇 |
1977年 | 11篇 |
1976年 | 3篇 |
1975年 | 8篇 |
1974年 | 4篇 |
1972年 | 8篇 |
1970年 | 5篇 |
排序方式: 共有1271条查询结果,搜索用时 328 毫秒
41.
D McWhirter M den Dulk M Terlizzo HZ Malik SW Fenwick GJ Poston 《Annals of the Royal College of Surgeons of England》2013,95(8):e136-e138
A 74-year old man underwent a radical cholecystectomy for presumed gallbladder cancer. The histology of the resected specimen in fact revealed the lesion to be metastatic renal cell carcinoma from his resected right nephrectomy performed 14 years previously. 相似文献
42.
The effect of low-intensity pulsed ultrasound on repair of epithelial cell monolayers in vitro 总被引:3,自引:0,他引:3
Hill GE Fenwick S Matthews BJ Chivers RA Southgate J 《Ultrasound in medicine & biology》2005,31(12):1701-1706
Low intensity pulsed ultrasound (LIPUS) is widely used to accelerate tissue regeneration following injury, but the biological mechanisms of this effect are poorly understood. An in vitro model of epithelial wound healing was used to investigate the effect of LIPUS on the reepithelialization of scrape wounds in normal human urothelial (NHU) cell monolayers. The effects of clinical doses of ultrasound treatment on NHU cell growth and migration were investigated in cells grown under optimal conditions, without growth supplements and in media containing low vs. physiological calcium concentrations. No differences in cell growth or migration were observed. We conclude that there is no direct effect upon uro-epithelial regeneration by therapeutic ultrasound in vitro and suggest that any stimulation of epithelial wound repair in vivo may occur indirectly, for example by modulating the extracellular matrix composition and/or production of paracrine factors by the stroma. 相似文献
43.
AIM: This paper is a report of a study to identify research priorities of clinical staff working with families at a Western Australian centre for parenting. BACKGROUND: Australian centres for parenting focus on children's needs while working in partnership with parents, families and their communities. These agencies incorporate primary healthcare strategies in their unique approach with families. Clinicians' research priorities at these centres have not been explored in an Australian context. METHOD: In 2005, a Delphi study was conducted in which clinicians were asked to provide a list of five important issues relating to care provided to children, parents and their families. Research topics identified were then ranked for their importance to the family and clinicians. Finally, the top 10 research topics were ranked for priority. FINDINGS: In round 1, 148 research topics were identified. Thirty-six topics were removed, due to the availability of existing evidence. Content analysis was used to collapse statements into 26 research questions, which were further classified into seven categories: parenting issues; sleep and settling issues; postnatal depression; evaluation and impact of programmes; staffing issues; centre marketing services and others. Issues relating to sleep and settling and postnatal depression were rated as top research priorities. CONCLUSION: The priorities of clinicians working with families provide research direction for this Western Australian centre and potentially other centres in Australia and similar settings elsewhere in the world. The Delphi approach in determining clinicians' perceptions of relevant research areas may be useful to direct research in other contexts. 相似文献
44.
Association between tetracycline or doxycycline and hepatotoxicity: a population based case-control study 总被引:1,自引:0,他引:1
BACKGROUND AND OBJECTIVE: An FDA Working Group, along with representatives of PhRMA and the American Association for the Study of Liver Diseases, as well as the Institute of Medicine Report 'To Err is Human: Building a Safer Health Care System' have suggested that post-marketing drug surveillance is a important method to decrease adverse drug events. While tetracyclines are known to cause hepatotoxicity, no post-marketing drug surveillance studies have examined the risk of developing hepatotoxicity with tetracyclines. Therefore, the objective of this study is to determine the difference in risk of hepatotoxicity in patients receiving doxycycline or tetracycline using California Medicaid claims. METHODS: This study used a retrospective, matched case-control study using California Medicaid claims data. The cases were defined as recipients who had at least one diagnosis of hepatotoxicity any time from 1 July 1999 to 31 December 2001. One control was identified for each case, matched on age, gender and race. Logistic regression was used to determine the adjusted odds ratio (OR) and 95% confidence intervals for current users and past users of tetracycline and doxycycline. Covariates controlled for in the analysis were age, use of other hepatotoxic drugs, renal dysfunction, pregnancy, and alcohol or illicit drug use. RESULTS: A total of 3377 cases of hepatotoxicity were identified. Current users and past users of tetracycline had a statistically significant increased risk of developing hepatotoxicity (current use OR 3.70, 95% CI 1.19-11.45; past use OR 2.72, 95% CI 1.26-5.85). Current users or past users of doxycycline did not have an increased risk of developing hepatotoxicity (current use OR 1.49, 95% CI 0.61-3.62; past use OR 1.74, 95% CI 0.99-3.06). Tetracycline was commonly used for acne, acute bronchitis and upper respiratory infections. Doxycycline was commonly used for acute bronchitis, vaginitis and acne. DISCUSSION AND CONCLUSION: Doxycycline was potentially less hepatotoxic than tetracycline. Doxycycline could potentially be a safe substitute for tetracycline, when appropriate. 相似文献
45.
46.
Stroke and conversion to high risk in children screened with transcranial Doppler ultrasound during the STOP study
下载免费PDF全文
![点击此处可从《Blood》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Adams RJ Brambilla DJ Granger S Gallagher D Vichinsky E Abboud MR Pegelow CH Woods G Rohde EM Nichols FT Jones A Luden JP Bowman L Hagner S Morales KH Roach ES;STOP Study 《Blood》2004,103(10):3689-3694
The Stroke Prevention Trial in Sickle Cell Anemia (STOP) was a randomized multicenter controlled trial comparing prophylactic blood transfusion with standard care in sickle cell anemia (SCA) children aged 2 to 16 years selected for high stroke risk by transcranial Doppler (TCD). More than 2000 children were screened with TCD to identify the 130 high-risk children who entered the randomized trial. A total of 5613 TCD studies from 2324 children were evaluated. We also collected information on stroke. We describe the changes in TCD with repeated testing and report the outcome without transfusion in the STOP screened cohort. Risk of stroke was higher with abnormal TCD than with normal or conditional TCD (P <.001) or inadequate TCD (P =.002), and risk with conditional TCD was higher than with normal TCD (P <.001). Repeated TCD in 1215 children showed that the condition of 9.4% of children became abnormal during observation. Younger patients and those with higher initial flow velocities were most likely to convert to abnormal TCDs. Screening in STOP confirmed the predictive value of TCD for stroke. Substantial differences in the probability of conversion to abnormal TCD were observed, with younger children and those with higher velocity more likely to have an abnormal TCD with rescreening. 相似文献
47.
48.
目的:分析血管紧张素原基因启动子区A-20C和A-6G单核苷酸多态性与蒙古族人群原发性高血压的相关性。方法:实验于2005-08/2006-01在北京华大实验室完成。选取对象均为生活在内蒙古乌拉特后旗的蒙古族牧民,三代血亲内无其他民族。采用基因测序技术对内蒙古蒙古族人群中107例原发性高血压患者和108例正常对照者进行A-20C和A-6G基因分型,观察高血压组和正常对照组不同基因型的分布和等位基因频率的差异。结果:①两组受试者在性别、年龄及吸烟、饮酒、体质量指数和临床化验检查指标有较好的匹配(P均>0.05)。②两组血管紧张素原基因A-20C位点AA,AC,CC基因型频率比较差异无显著性意义(高血压组分别为0.51,0.29,0.20;正常对照组分别为0.49,0.28,0.23,χ2=0.395,P=0.529)。A,C等位基因频率比较差异无显著性意义(高血压组分别为0.65,0.35;正常对照组分别为0.63,0.37,χ2=0.015,P=0.904)。③两组血管紧张素原基因A-6G位点AA,AG,GG基因型频率比较差异无显著性意义(高血压组分别为0.50,0.33,0.17;正常对照组分别为0.55,0.34,0.11,χ2=1.924,P=0.165)。A,G等位基因频率比较差异无显著性意义(高血压组分别为0.66,0.34;正常对照组分别为0.72,0.28,χ2=1.728,P=0.189)。④高血压组协同存在血管紧张素原基因A-20C基因型CC时,血管紧张素原基因A-6G基因型GG频率稍高于正常对照组,但差异无显著性意义(χ2=2.395,P=0.122,OR=7.52,95%CI0.014~1.250),高血压组G等位基因明显高于正常对照组(分别为0.37,0.22,χ2=4.658,P=0.034),携带该等位基因的蒙古族人群发生原发性高血压的相对危险度升高(OR=2.80,95%CI1.087~7.271)。结论:血管紧张素原基因A-20C和A-6G单核苷酸多态性与蒙古族人群原发性高血压相关,并可能具有协同作用。 相似文献
49.
This paper reports the findings of the postnatal qualitative arm of a larger study, which investigated women's prenatal and postnatal levels of childbirth fear. Women's expectations and experiences of labour and birth in a Western Australian public tertiary hospital were identified following thematic analysis of short written accounts from 141 participants who had given birth in the previous 6 to 14 weeks. Four major categories emerged to describe features and mediating factors in the trajectory of childbirth and the early puerperium. "Anticipating Labour and Birth," "Labour and Birth Depicted," "Mediating Factors and their Consequences," and "Evaluating, Resolving, and Looking Ahead" portray women's comparative reflections on expectations and realities of birth, on mediating influences, and on moving on from their experience. These findings will provide maternity care professionals with insight into the personal and environmental features of the childbirth setting which colours women's recollections. Being aware of what women value during labour and birth will reinforce the need for professionals to provide care using a mindful approach that considers the potential psychological, emotional, and behavioural implications of events. 相似文献
50.
Songhua Shan Trevor Ellis Stan Fenwick John Edwards Mark O’Dea John Parkinson 《Archives of virology》2010,155(3):403-409
Influenza A virus, A/Eurasian coot/Western Australia/2727/79 (H6N2), from an apparently healthy coot was characterized. This
virus was able to grow on MDCK cells and produce a cytopathic effect in the absence of exogenous trypsin and was further characterized
as a low-pathogenicity avian influenza virus, with an intravenous pathogenicity index of 0.15 and a 321PQAETRG328 motif at the cleavage site of the haemagglutinin gene. It infected domestic chickens, resulting in seroconversion and intermittent
virus excretion via cloaca and oropharynx under experimental conditions. Phylogenetic analysis showed that the viral genes
were closely related to other waterfowl isolates from the same geographic area and time period. 相似文献