全文获取类型
收费全文 | 184137篇 |
免费 | 1388篇 |
国内免费 | 59篇 |
专业分类
耳鼻咽喉 | 1235篇 |
儿科学 | 6769篇 |
妇产科学 | 3203篇 |
基础医学 | 17490篇 |
口腔科学 | 1783篇 |
临床医学 | 12966篇 |
内科学 | 33216篇 |
皮肤病学 | 799篇 |
神经病学 | 17401篇 |
特种医学 | 9144篇 |
外科学 | 29923篇 |
综合类 | 2329篇 |
一般理论 | 3篇 |
预防医学 | 18447篇 |
眼科学 | 2917篇 |
药学 | 10074篇 |
中国医学 | 637篇 |
肿瘤学 | 17248篇 |
出版年
2023年 | 64篇 |
2022年 | 145篇 |
2021年 | 265篇 |
2020年 | 166篇 |
2019年 | 220篇 |
2018年 | 22100篇 |
2017年 | 17516篇 |
2016年 | 19686篇 |
2015年 | 1128篇 |
2014年 | 1108篇 |
2013年 | 1240篇 |
2012年 | 7611篇 |
2011年 | 21655篇 |
2010年 | 19133篇 |
2009年 | 11835篇 |
2008年 | 20086篇 |
2007年 | 22320篇 |
2006年 | 1199篇 |
2005年 | 2778篇 |
2004年 | 3980篇 |
2003年 | 4875篇 |
2002年 | 2964篇 |
2001年 | 322篇 |
2000年 | 458篇 |
1999年 | 201篇 |
1998年 | 299篇 |
1997年 | 270篇 |
1996年 | 164篇 |
1995年 | 171篇 |
1994年 | 162篇 |
1993年 | 118篇 |
1992年 | 77篇 |
1991年 | 111篇 |
1990年 | 156篇 |
1989年 | 106篇 |
1988年 | 69篇 |
1987年 | 57篇 |
1986年 | 42篇 |
1985年 | 44篇 |
1984年 | 37篇 |
1983年 | 38篇 |
1982年 | 41篇 |
1981年 | 24篇 |
1980年 | 50篇 |
1974年 | 23篇 |
1938年 | 60篇 |
1937年 | 25篇 |
1934年 | 30篇 |
1932年 | 56篇 |
1930年 | 46篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Ward A. Heggermont Marc Goethals Riet Dierckx Sofie Verstreken Jozef Bartunek Marc Vanderheyden 《Heart failure reviews》2016,21(6):699-701
The brand new 2016 ESC guidelines for the treatment of acute and chronic heart failure continue to give a prominent place to mineralocorticoid receptor antagonists in the treatment of chronic heart failure with reduced ejection fraction (HFrEF). In the prevention of HF hospitalization and death, a class I, level of recommendation A, is given to MRAs for patients with HFrEF, who remain symptomatic despite treatment with an ACE-inhibitor and a beta-blocker and have an LVEF below 35 %. This recommendation is primarily based on two landmark trials, the RALES trial (for spironolactone) and the EMPHASIS-HF trial (for eplerenone). A crucial question is, however, why MRAs are advised only in “third place,” i.e., after optimal up-titration of ACE-inhibitors and beta-blockers. We wonder whether MRAs could not or should not be given earlier in the treatment of HFrEF, namely before or together with the up-titration of ACE-inhibitors and beta-blockers. Several arguments to support this plea are described in this short paper. 相似文献
992.
Heart failure is a major health problem worldwide and, despite effective therapies, is expected to grow by almost 50 % over the next 15 years. Five-year mortality remains high at 50 % over 5 years. Because of the economic burden and large impact on quality of life, substantial effort has focused on treatments with multiple medical (beta-blockers, angiotensin-converting enzyme inhibitors and angiotensin receptor blockers (ARB), aldosterone antagonists, and combination of ARB/neprilysin blockers, ivabradine) and device therapies (ICD, CRT) which have been implemented to reduce disease burden and mortality. However, in the past decade only two new medical therapies and no devices have been approved by the US FDA for the treatment of heart failure. This review highlights the preclinical and clinical literature, and the implantation procedure, related to a relatively new therapeutic device for heart failure; cardiac contractility modulation (CCM). CCM delivers a biphasic high-voltage bipolar signal to the RV septum during the absolute refractory period, eliciting an acute increase in global contractility, and chronically producing a sustained improvement in quality of life, exercise tolerance, and heart failure symptoms. The technology is used commercially in Europe with nearly 3000 patients implanted worldwide. Indications include patients with reduced EF and normal or slightly prolonged QRS duration, thus filling an important therapeutic gap among the 2/3 of patients with heart failure who do not meet criteria for CRT. The mechanism by which CCM provides benefit can be seen at the cellular level where improved calcium handling (phosphorylation of phospholamban, upregulation of SERCA-2A), reversal of the fetal myocyte gene program associated with heart failure, and reverse remodeling are observed. Recent retrospective studies indicate a long-term mortality benefit. A pivotal randomized controlled study is currently being completed in the USA. CCM appears to be an effective, safe technology for the treatment of heart failure with reduced ejection fraction. 相似文献
993.
Josh Mitteldorf 《Biogerontology》2016,17(1):257-265
We are accustomed to treating aging as a set of things that go wrong with the body. But for more than twenty years, there has been accumulating evidence that much of the process takes place under genetic control. We have seen that signaling chemistry can make dramatic differences in life span, and that single molecules can significantly affect longevity. We are frequently confronted with puzzling choices the body makes which benefit neither present health nor fertility nor long-term survival. If we permit ourselves a shift of reference frame and regard aging as a programmed biological function like growth and development, then these observations fall into place and make sense. This perspective suggests that aging proceeds under control of a master clock, or several redundant clocks. If this is so, we may learn to reset the clocks with biochemical interventions and make an old body behave like a young body, including repair of many of the modes of damage that we are accustomed to regard as independent symptoms of the senescent phenotype, and for which we have assumed that the body has no remedy. 相似文献
994.
Oral sensations (i.e., taste, oral somatosensation, retronasal olfaction) are integrated into a composite sense of flavor, which guides dietary choices with long-term health impact. The nerves carrying this input are vulnerable to peripheral damage from multiple sources (e.g., otitis media, tonsillectomy, head injury), and this regional damage can boost sensations elsewhere in the mouth because of central interactions among nerve targets. Mutual inhibition governs this compensatory process, but individual differences lead to variation in whole-mouth outcomes: some individuals are unaffected, others experience severe loss, and some encounter sensory increases that may (if experienced early in life) elevate sweet-fat palatability and body mass. Phantom taste, touch, or pain sensations (e.g., burning mouth syndrome) may also occur, particularly in those expressing the most taste buds. To identify and treat these conditions effectively, emerging clinical tests measure regional vs. whole-mouth sensation, stimulated vs. phantom cues, and oral anatomy. Scaling methods allowing valid group comparisons have strongly aided these efforts. Overall, advances in measuring oral sensory function in health and disease show promise for understanding the varied clinical consequences of nerve damage. 相似文献
995.
Julie A. Mennella Nuala K. Bobowski Danielle R. Reed 《Reviews in endocrine & metabolic disorders》2016,17(2):171-178
From the age of 2 years, an American child is more likely to consume a sugar-sweetened product than a fruit or vegetable on any given day—a troubling statistic, given that food preferences are established early in childhood, as well as the strong association between this dietary pattern and increased risk of developing a number of chronic diseases. Here, we review the ontogeny and biopsychology of sweet taste, highlighting how a biological drive to prefer sweetness at high concentrations during childhood, which would have conferred an advantage in environments of scarcity, now predisposes children to overconsume all that is sweet in a modern food system replete with added sugars. We review the power of sweet taste to blunt expressions of pain and mask bad tastes in foods as well as factors that predispose some to consume high-sugar diets, including experiential learning and taste preferences driven in part by genetics. Understanding children’s unique vulnerability to our current food environment, rich in both nutritive and nonnutritive sweeteners, is highlighted as a priority for future research to develop evidence-based strategies to help establish healthy dietary behaviors early in life. 相似文献
996.
997.
Stefano Omboni Igor N. Posokhov Yulia V. Kotovskaya Athanase D. Protogerou Jacques Blacher 《Current hypertension reports》2016,18(10):72
The predictive value of vascular biomarkers such as pulse wave velocity (PWV), central arterial pressure (CAP), and augmentation index (AIx), obtained through pulse wave analysis (PWA) in resting conditions, has been documented in a variety of patient groups and populations. This allowed to make appropriate recommendations in clinical practice guidelines of several scientific societies. Due to advances in technologies, largely operator-independent methods are currently available for estimating vascular biomarkers also in ambulatory conditions, over the 24 h. According to the acceptable accuracy and reproducibility of 24-h ambulatory PWA, it appears to be a promising tool for evaluating vascular biomarkers in daily life conditions. This approach may provide an opportunity to further improve the early cardiovascular screening in subjects at risk. However, concerning the clinical use of PWA over the 24 h in ambulatory conditions at the moment, there is no sufficient evidence to support its routine clinical use. In particular, long-term outcome studies are needed to show the predictive value of 24-h PWV, CAP, and AIx values, provided by these devices, over and beyond peripheral blood pressure, and to answer the many technical and clinical questions still open. To this regard, the VASOTENS Registry, an international observational prospective study recently started, will help providing answers on a large sample of hypertensive patients recruited worldwide. 相似文献
998.
Samir G. Mallat Sahar Al Kattar Bassem Y. Tanios Abdo Jurjus 《Current hypertension reports》2016,18(10):74
Uric acid is a product of purine metabolism and has been linked to gout and kidney calculi. Chronic kidney disease (CKD) and hypertension (HTN) are two major public health problems, and both are associated with increased risk of cardiovascular events. Emerging evidence suggests a pathogenic role of hyperuricemia in the development of HTN and CKD, in addition to progression of CKD, by inducing renal inflammation, endothelial dysfunction, and activation of the renin-angiotensin system. In addition, several epidemiological studies have linked hyperuricemia with an increased risk of HTN and CKD. A few clinical trials have assessed the use of uric acid-lowering therapies such as allopurinol and febuxostat in the management of HTN and delaying progression of CKD. To date, most of these trials are short-term with a small sample size; however, their results are encouraging and provide a rationale for larger randomized controlled trials to establish the role of uric acid-lowering therapies in the management of HTN, in addition to prevention of CKD progression and cardiovascular events. 相似文献
999.
The utilization of impedance technology has enhanced our understanding and assessment of esophageal dysmotility. Esophageal high-resolution manometry (HRM) catheters incorporated with multiple impedance electrodes help assess esophageal bolus transit, and the combination is termed high-resolution impedance manometry (HRIM). Novel metrics have been developed with HRIM—including esophageal impedance integral ratio, bolus flow time, nadir impedance pressure, and impedance bolus height—that augments the assessment of esophageal bolus transit. Automated impedance-manometry (AIM) analysis has enhanced understanding of the relationship between bolus transit and pressure phenomena. Impedance-based metrics have improved understanding of the dynamics of esophageal bolus transit into four distinct phases, may correlate with symptomatic burden, and can assess the adequacy of therapy for achalasia. An extension of the use of impedance involves impedance planimetry and the functional lumen imaging probe (FLIP), which assesses esophageal biophysical properties and distensibility, and could detect patterns of esophageal contractility not seen on HRM. Impedance technology, therefore, has a significant impact on esophageal function testing in the present day. 相似文献
1000.
Alexander Kroemer Christopher Cosentino Jason Kaiser Cal S. Matsumoto Thomas M. Fishbein 《Current gastroenterology reports》2016,18(11):56
Intestinal transplantation is the most immunologically complex of all abdominal organ transplants. Understanding the role both humoral and innate and adaptive cellular immunity play in intestinal transplantation is critical to improving outcomes and increasing indications for patients suffering from intestinal failure. Recent findings highlighting the impact of donor-specific antibodies on intestinal allografts, the role of NOD2 as a key regulator of intestinal immunity, the protective effects of innate lymphoid cells, and the role of Th17 in acute cellular rejection are reviewed here. 相似文献