全文获取类型
收费全文 | 1003篇 |
免费 | 62篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 24篇 |
儿科学 | 47篇 |
妇产科学 | 10篇 |
基础医学 | 101篇 |
口腔科学 | 28篇 |
临床医学 | 91篇 |
内科学 | 206篇 |
皮肤病学 | 15篇 |
神经病学 | 45篇 |
特种医学 | 18篇 |
外科学 | 220篇 |
综合类 | 24篇 |
一般理论 | 3篇 |
预防医学 | 52篇 |
眼科学 | 29篇 |
药学 | 122篇 |
中国医学 | 7篇 |
肿瘤学 | 27篇 |
出版年
2024年 | 1篇 |
2023年 | 18篇 |
2022年 | 44篇 |
2021年 | 49篇 |
2020年 | 27篇 |
2019年 | 47篇 |
2018年 | 50篇 |
2017年 | 38篇 |
2016年 | 30篇 |
2015年 | 26篇 |
2014年 | 40篇 |
2013年 | 58篇 |
2012年 | 94篇 |
2011年 | 108篇 |
2010年 | 52篇 |
2009年 | 43篇 |
2008年 | 64篇 |
2007年 | 58篇 |
2006年 | 42篇 |
2005年 | 38篇 |
2004年 | 37篇 |
2003年 | 28篇 |
2002年 | 21篇 |
2001年 | 13篇 |
2000年 | 6篇 |
1999年 | 10篇 |
1998年 | 4篇 |
1997年 | 5篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 4篇 |
1990年 | 1篇 |
1987年 | 1篇 |
1985年 | 2篇 |
1982年 | 2篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1970年 | 1篇 |
1969年 | 2篇 |
排序方式: 共有1069条查询结果,搜索用时 15 毫秒
41.
Jaya Chandrasekhar Usman Baber Samantha Sartori Melissa Aquino Annapoorna S. Kini Sunil Rao William Weintraub Timothy D. Henry Serdar Farhan Birgit Vogel Sabato Sorrentino Zhen Ge Samir Kapadia Joseph B. Muhlestein Sandra Weiss Craig Strauss Catalin Toma Anthony DeFranco Roxana Mehran 《The Canadian journal of cardiology》2018,34(3):319-329
Background
Potent P2Y12 inhibitors might offer enhanced benefit against thrombotic events in complex percutaneous coronary intervention (PCI). We examined prasugrel use and outcomes according to PCI complexity, as well as analyzing treatment effects according to thienopyridine type.Methods
PROMETHEUS was a multicentre observational study that compared clopidogrel vs prasugrel in acute coronary syndrome patients who underwent PCI (n = 19,914). Complex PCI was defined as PCI of the left main, bifurcation lesion, moderate-severely calcified lesion, or total stent length ≥ 30 mm. Major adverse cardiac events (MACE) were a composite of death, myocardial infarction, stroke, or unplanned revascularization. Outcomes were adjusted using multivariable Cox regression for effect of PCI complexity and propensity-stratified analysis for effect of thienopyridine type.Results
The study cohort included 48.9% (n = 9735) complex and 51.1% (n = 10,179) noncomplex patients. Second generation drug-eluting stents were used in 70.1% complex and 66.2% noncomplex PCI patients (P < 0.0001). Complex PCI was associated with greater adjusted risk of 1-year MACE (hazard ratio [HR], 1.29; 95% confidence interval [CI], 1.20-1.39; P < 0.001). Prasugrel was prescribed in 20.7% of complex and 20.1% of noncomplex PCI patients (P = 0.30). Compared with clopidogrel, prasugrel significantly decreased adjusted risk for 1-year MACE in complex PCI (HR, 0.79; 95% CI, 0.68-0.92) but not noncomplex PCI (HR, 0.91; 95% CI, 0.77-1.08), albeit there was no evidence of interaction (P interaction = 0.281).Conclusions
Despite the use of contemporary techniques, acute coronary syndrome patients who undergo complex PCI had significantly higher rates of 1-year MACE. Adjusted magnitude of treatment effects with prasugrel vs clopidogrel were consistent in complex and noncomplex PCI without evidence of interaction. 相似文献42.
43.
The month of Ramadan forms one of the five pillars of the Muslim faith. Adult Muslims are obligated to keep daily fasts from dawn to sunset, with exceptions. This year Ramadan is due to begin on 23 April 2020 and the longest fast in the UK will be approximately 18 hours in length. In addition, due to the often high-calorie meals eaten to break the fast, Ramadan should be seen as a cycle of fasting and feasting. Ramadan fasting can impact those with diabetes, increasing the risk of hypoglycaemia, hyperglycaemia and dehydration. This year, Ramadan will occur during the global COVID-19 pandemic. Reports show that diabetes appears to be a risk factor for more severe disease with COVID-19. In addition, the UK experience has shown diabetes and COVID-19 is associated with dehydration, starvation ketosis, diabetic ketoacidosis and hyperosmolar hyperglycaemic state. This makes fasting in Ramadan particularly challenging for those Muslims with diabetes. Here, we discuss the implications of fasting in Ramadan during the COVID-19 pandemic and make recommendations for those with diabetes who wish to fast. 相似文献
44.
Jason J. S. Barton Hashim M. Hanif Laura Eklinder Björnström Charlotte Hills 《Cognitive neuropsychology》2014,31(5-6):378-412
The finding that visual processing of a word correlates with the number of its letters has an extensive history. In healthy subjects, a variety of methods, including perceptual thresholds, naming and lexical decision times, and ocular motor parameters, show modest effects that interact with high-order effects like frequency. Whether this indicates serial processing of letters under some conditions or indexes low-level visual factors related to word length is unclear. Word-length effects are larger in pure alexia, where they probably reflect a serial letter-by-letter strategy, due to failure of lexical whole-word processing and variable dysfunction in letter encoding. In pure alexia, the word-length effect is systematically related to mean naming latency, with the word-length effect becoming proportionally greater as naming latency becomes more delayed in severe cases. Other conditions may also generate enhanced word-length effects. This occurs in right hemianopia: Computer simulations suggest a criterion of 160?ms/letter to distinguish hemianopic dyslexia from pure alexia. Normal reading development is accompanied by a decrease in word-length effects, whereas persistently elevated word-length effects are characteristic of developmental dyslexia. Little is known about word-length effects in other reading disorders. We conclude that the word-length effect captures the efficiency of the perceptual reading process in development, normal reading, and a number of reading disorders, even if its mechanistic implications are not always clear. 相似文献
45.
Muhammad Imran Tanweer Aslam Gondal Muhammad Atif Muhammad Shahbaz Tahira Batool Qaisarani Muhammad Hanif Mughal Bahare Salehi Miquel Martorell Javad Sharifi‐Rad 《Phytotherapy research : PTR》2020,34(8):1812-1828
Apigenin is an edible plant‐derived flavonoid that has been reported as an anticancer agent in several experimental and biological studies. It exhibits cell growth arrest and apoptosis in different types of tumors such as breast, lung, liver, skin, blood, colon, prostate, pancreatic, cervical, oral, and stomach, by modulating several signaling pathways. Apigenin induces apoptosis by the activation of extrinsic caspase‐dependent pathway by upregulating the mRNA expressions of caspase‐3, caspase‐8, and TNF‐α. It induces intrinsic apoptosis pathway as evidenced by the induction of cytochrome c, Bax, and caspase‐3, while caspase‐8, TNF‐α, and B‐cell lymphoma 2 levels remained unchanged in human prostate cancer PC‐3 cells. Apigenin treatment leads to significant downregulation of matrix metallopeptidases‐2, ?9, Snail, and Slug, suppressing invasion. The expressions of NF‐κB p105/p50, PI3K, Akt, and the phosphorylation of p‐Akt decreases after treatment with apigenin. However, apigenin‐mediated treatment significantly reduces pluripotency marker Oct3/4 protein expression which might be associated with the downregulation of PI3K/Akt/NF‐κB signaling. 相似文献
46.
Faisal Saleem Abdul Rehman Farhan Ahmad Asif Hussain Khoja Farhan Javed Kui Zhang Adam Harvey 《RSC advances》2021,11(44):27583
Methane is the main component of biogas, which could be used as a renewable energy source for electricity, source of heat, and biofuel production after upgrading from biogas. It also contains toxic compounds which cause environmental and human health problems. Therefore, in this work, the removal of a toxic compound (toluene) from methane gas was studied using a dielectric barrier discharge (DBD) reactor. It was observed that the removal of the toxic compound could be achieved from methane carrier gas using a dielectric barrier discharge reactor, and it depends on plasma input power. The maximum removal of the toxic compound was 85.9% at 40 W and 2.86 s. The major gaseous products were H2 and lower hydrocarbons (LHC) and the yield of these products also increases with input power. In the current study, the yield of gaseous products depends on the decomposition of toxic compounds and methane, because the decomposition of methane also produces H2 and lower hydrocarbons. The percentage yield of H2 increases from 0.43–4.74%. Similarly, the yield of LHC increases from 0.56–7.54% under the same reaction conditions. Hence, input power promoted the decomposition of the toxic compound and enhanced the yield of gaseous products.The removal of toluene as a toxic volatile organic compound from methane gas, which is the major component of biogas, is carried out using a non-thermal plasma dielectric barrier discharge reactor. 相似文献
47.
48.
Kiersten E. Norby Farhan Siddiq Malik M. Adil Saqib A. Chaudhry Adnan I. Qureshi 《Neurocritical care》2013,18(2):170-177
Background
Intracerebral hemorrhage (ICH) is an infrequent complication of intravenous recombinant tissue plasminogen activator (rt-PA) for the treatment of acute stroke. However, such ICH is an important reason for withdrawal of care because of lack of adequate data regarding long-term patient outcomes.Objective
To report the long-term outcomes in patients with post-thrombolytic ICH.Methods
We analyzed patient data from a randomized, placebo-controlled trial in patients with ischemic stroke presenting within 3 h of symptom onset. Baseline clinical characteristics and outcomes defined by modified Rankin scale (mRS) were ascertained at 3, 6, and 12 months after treatment in patients who suffered from post-thrombolytic ICH. Favorable outcome was defined by mRS of 0–3 and unfavorable outcome by mRS of 4–6 at 1 year.Results
A total of 48 patients suffered post-thrombolytic ICH in the trial. Fourteen patients had favorable outcomes and 34 patients had unfavorable outcomes. Clinical characteristics did not have an impact on patient outcomes at 12 months. Patients with unfavorable outcomes were more likely to have an National Institutes of Health Stroke Scale (NIHSS) score ≥20 at 7–10 days after treatment (64 vs. 7 %, p < 0.0009). Patients with unfavorable outcomes were more likely to have a worsening of NIHSS score of >4 points at 7–10 days from their baseline NIHSS (44 vs. 0 %, p = 0.0006).Conclusion
Approximately 30 % of patients with post-thrombolytic ICH have favorable outcomes at 1 year which does not support early withdrawal of care. Ascertainment of NIHSS score and worsening of NIHSS score at 7–10 days may be necessary for accurate prognostic stratification. 相似文献49.
Elsa Ahlén Charlotte S. Hills Hashim M. Hanif Cristina Rubino Jason J. S. Barton 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2014,232(3):1025-1036
Reading is an expert visual and ocular motor function, learned mainly in a single orientation. Characterizing the features of this expertise can be accomplished by contrasts between reading of normal and inverted text, in which perceptual but not linguistic factors are altered. Our goal was to examine this inversion effect in healthy subjects reading text, to derive behavioral and ocular motor markers of perceptual expertise in reading, and to study these parameters before and after training with inverted reading. Seven subjects engaged in a 10-week program of 30 half-hour sessions of reading inverted text. Before and after training, we assessed reading of upright and inverted single words for response time and word-length effects, as well as reading of paragraphs for time required, accuracy, and ocular motor parameters. Before training, inverted reading was characterized by long reading times and large word-length effects, with eye movements showing more and longer fixations, more and smaller forward saccades, and more regressive saccades. Training partially reversed many of these effects in single word and text reading, with the best gains occurring in reading aloud time and proportion of regressive saccades and the least change in forward saccade amplitude. We conclude that reading speed and ocular motor parameters can serve as markers of perceptual expertise during reading and that training with inverted text over 10 weeks results in significant gains of reading expertise in this unfamiliar orientation. This approach may be useful in the rehabilitation of patients with hemianopic dyslexia. 相似文献
50.
da Silva Xavier G Farhan H Kim H Caxaria S Johnson P Hughes S Bugliani M Marselli L Marchetti P Birzele F Sun G Scharfmann R Rutter J Siniakowicz K Weir G Parker H Reimann F Gribble FM Rutter GA 《Diabetologia》2011,54(4):819-827