全文获取类型
收费全文 | 1170篇 |
免费 | 78篇 |
国内免费 | 11篇 |
专业分类
耳鼻咽喉 | 8篇 |
儿科学 | 11篇 |
妇产科学 | 8篇 |
基础医学 | 182篇 |
口腔科学 | 9篇 |
临床医学 | 124篇 |
内科学 | 247篇 |
皮肤病学 | 20篇 |
神经病学 | 123篇 |
特种医学 | 124篇 |
外科学 | 148篇 |
综合类 | 10篇 |
预防医学 | 43篇 |
眼科学 | 4篇 |
药学 | 131篇 |
中国医学 | 1篇 |
肿瘤学 | 66篇 |
出版年
2023年 | 16篇 |
2022年 | 54篇 |
2021年 | 77篇 |
2020年 | 32篇 |
2019年 | 40篇 |
2018年 | 55篇 |
2017年 | 25篇 |
2016年 | 35篇 |
2015年 | 43篇 |
2014年 | 54篇 |
2013年 | 73篇 |
2012年 | 78篇 |
2011年 | 96篇 |
2010年 | 51篇 |
2009年 | 40篇 |
2008年 | 59篇 |
2007年 | 64篇 |
2006年 | 55篇 |
2005年 | 50篇 |
2004年 | 41篇 |
2003年 | 43篇 |
2002年 | 29篇 |
2001年 | 8篇 |
2000年 | 10篇 |
1999年 | 5篇 |
1998年 | 8篇 |
1997年 | 3篇 |
1991年 | 4篇 |
1990年 | 4篇 |
1989年 | 4篇 |
1988年 | 4篇 |
1987年 | 6篇 |
1986年 | 6篇 |
1985年 | 7篇 |
1984年 | 9篇 |
1983年 | 3篇 |
1980年 | 4篇 |
1979年 | 7篇 |
1978年 | 4篇 |
1977年 | 6篇 |
1976年 | 6篇 |
1975年 | 3篇 |
1972年 | 2篇 |
1971年 | 3篇 |
1970年 | 2篇 |
1940年 | 2篇 |
1938年 | 2篇 |
1937年 | 2篇 |
1932年 | 2篇 |
1928年 | 3篇 |
排序方式: 共有1259条查询结果,搜索用时 0 毫秒
41.
Walter Fiedler Joerg Chromik Stefanie Amberg Maxim Kebenko Felicitas Thol Vera Schlipfenbacher Anne Christine Wilke Franziska Modemann Melanie Janning Hubert Serve Arnold Ganser Carsten Bokemeyer Susann Theile Ute Deppermann Anne L. Kranich Michael Heuser 《British journal of haematology》2020,190(3):e169-e173
42.
Bharmal Sakina Huseni Cho Jaelim Alarcon Ramos Gisselle Charlott Ko Juyeon Stuart Charlotte Elizabeth Modesto Andre Eto Singh Ruma Girish Petrov Maxim Sergey 《Journal of gastroenterology》2020,55(8):775-788
Journal of Gastroenterology - New-onset diabetes is the most common sequela of acute pancreatitis (AP). Yet, prospective changes in glycaemia over time have never been investigated comprehensively... 相似文献
43.
44.
Lomani Archibald O’Hagan John Albert Windsor Anthony Ronald John Phillips Maxim Itkin Peter Spencer Russell Seyed Ali Mirjalili 《Journal of anatomy》2020,236(6):1146-1153
The majority of lymph generated in the body is returned to the blood circulation via the lymphovenous junction (LVJ) of the thoracic duct (TD). A lymphovenous valve (LVV) is thought to guard this junction by regulating the flow of lymph to the veins and preventing blood from entering the lymphatic system. Despite these important functions, the morphology and mechanism of this valve remains unclear. The aim of this study was to investigate the anatomy of the LVV of the TD. To do this, the TD and the great veins of the left side of the neck were harvested from 16 human cadavers. The LVJs from 12 cadavers were successfully identified and examined macroscopically, microscopically, and using microcomputed tomography. In many specimens, the TD branched before entering the veins. Thus, from 12 cadavers, 21 LVJs were examined. Valves were present at 71% of LVJs (15/21) and were absent in the remainder. The LVV, when present, was typically a bicuspid semilunar valve, although the relative size and position of its cusps were variable. Microscopically, the valve cusps comprised luminal extensions of endothelium with a thin core of collagenous extracellular matrix. This study clearly demonstrated the morphology of the human LVV. This valve may prevent blood from entering the lymphatic system, but its variability and frequent absence calls into question its utility. Further structural and functional studies are required to better define the role of the LVV in health and disease. 相似文献
45.
Georgii A. Illarionov Denis S. Kolchanov Oleg A. Kuchur Mikhail V. Zhukov Ekaterina Sergeeva Vladimir V. Krishtop Alexandr V. Vinogradov Maxim I. Morozov 《RSC advances》2019,9(62):35998
In this study we address a novel design of a planar memristor and investigate its biocompatibility. An experimental prototype of the proposed memristor assembly has been manufactured using a hybrid nanofabrication method, combining sputtering of electrodes, patterning the insulating trenches, and filling them with a memristive substance. To pattern the insulating trenches, we have examined two nanofabrication techniques employing either a focused ion beam or a cantilever tip of an atomic force microscope. Inkjet printing has been used to fill the trenches with the functional titania ink. The experimental prototypes have qualitatively demonstrated memristive current–voltage behavior, as well as high biocompatibility.A planar memristor was fabricated by a hybrid method combining AFM patterning and inkjet printing. 相似文献
46.
Jennifer A. Melanson Maxim F. Landry Martin Lanteigne Katherine McQuillan Hebelin Correa Russell G. Kerr Stephen A. Westcott 《RSC advances》2021,11(39):24282
This study reports on the preparation of eight new boron-containing capsaicinoids bearing long aliphatic chains, as an expansion of our previous studies to include tertiary amide derivatives into our substrate scope. Our boron-moiety, a pinacolboronate ester (Bpin) fragment, has been incorporated in two locations: as an aryl substituent of the capsaicinoid produced by the reductive amination of veratraldehyde, or at the terminal end of an aliphatic substituent using an iridium catalyzed hydroboration reaction. We report that most compounds in our series show moderate antimicrobial and cytotoxic activity, surpassing activities noted in our previous study.This study reports on the preparation of eight new boron-containing capsaicinoids bearing long aliphatic chains, and initial bioactivities are reported. 相似文献
47.
Sofiia A. Butonova Evgeniya V. Ikonnikova Aziza Sharsheeva Ivan Yu. Chernyshov Oleg A. Kuchur Ivan S. Mukhin Evamarie Hey-Hawkins Alexander V. Vinogradov Maxim I. Morozov 《RSC advances》2021,11(62):39169
The zeolitic imidazolate framework ZIF-8 (Zn(mim)2, mim = 2-methylimidazolate) has recently been proposed as a drug delivery platform for anticancer therapy based on its capability of decomposing in acidic media. The concept presumes a targeted release of encapsulated drug molecules in the vicinity of tumor tissues that typically produce secretions with elevated acidity. Due to challenges of in vivo and in vitro examination, many studies have addressed the kinetics of ZIF-8 decomposition and subsequent drug release in phosphate buffered saline (PBS) with adjusted acidity. However, the presence of hydrogen phosphate anions [HPO4]2− in PBS may also affect the stability of ZIF-8. As yet, no separate analysis has been performed comparing the dissolving capabilities of PBS and various acidification agents used for regulating pH. Here, we provide a systematic study addressing the effects of phosphate anions with and without lactic acid on the degradation rate of ZIF-8 microcrystals. Lactic acid has been chosen as an experimental acidification agent, since it is particularly secreted by tumor cells. Interestingly, the effect of a lactic acid solution with pH 5.0 on ZIF-8 degradation is shown to be weaker compared to a PBS solution with pH 7.4. However, as an additive, lactic acid is able to enhance the decomposition efficacy of other solutions by 10 to 40 percent at the initial stage, depending on the presence of other ions. Additionally, we report mild toxicity of ZIF-8 and its decomposition products, as examined on HDF and A549 cell lines.ZIF-8 microcrystals demonstrate different degradation kinetics in water, PBS (pH 7.4), and PBS with lactic acid (pH 5.0). 相似文献
48.
Kian Banks Sora Ely Diana S. Hsu Dana A. Dominguez Rebecca C. Gologorsky Julia Wei Clara Maxim Simon K. Ashiku Ashish R. Patel Jeffrey B. Velotta 《Journal of thoracic disease》2022,14(1):18
BackgroundIntercostal nerve blockade (INB) for thoracic surgery analgesia has gained popularity in practice, but evidence demonstrating its efficacy remains sparse and inconsistent. We investigated the effect of INB with standard bupivacaine (SB) with epinephrine versus liposomal bupivacaine (LB) versus a mixed solution of the two on postoperative pain control and outcomes in video assisted thoracoscopic lobectomy patients.MethodsSince 2014, our practice has shifted from using INBs with SB with epinephrine, to LB, to a mix of the two as the central component of multimodal analgesia after video assisted thoracoscopic surgery. The blocks are performed in a standardized fashion under thoracoscopic visualization consecutively from two rib spaces above to two below the outermost incisions. We retrospectively compared all minimally invasive lobectomies performed at our institution between January 2014 and July 2018 by type of local anesthetic used for INB. We examined median length of stay (LOS), opioid utilization, and subjective pain scores [0–10].ResultsOut of 302 minimally invasive lobectomy patients, 34 received SB with epinephrine, 222 received LB alone, and 46 received the mixed solution. LOS was almost a full day shorter in the LB group than in the SB group (34.8 vs. 56.5 hours, P=0.01). There was nearly 25% lower median total morphine equivalent utilization in the mixed solution cohort compared to the LB cohort (−7.1 mg, P=0.02). Additionally, IV morphine equivalent utilization was over 50% lower in the mixed solution group than in the SB with epinephrine group (−10.0 mg, P=0.03).ConclusionsOur study is by far the largest (N=302) to compare types of local anesthetic used for INB within a uniform case population. The reductions in LOS and opiate utilization observed in our study among patients receiving LB-based formulations were both statistically and clinically significant. 相似文献
49.
50.
Vitamins have many established roles in human health. However, the role of habitual dietary intake of vitamins in glucose homeostasis in individuals after acute pancreatitis (AP) is yet to be elucidated. The aim was to investigate the associations between habitual intake of fat- and water-soluble vitamins/vitamers and markers of glucose metabolism (fasting plasma glucose (FPG), homeostasis model assessment insulin resistance (HOMA-IR) index, and homeostasis model assessment β-cell function (HOMA-β)) in individuals after AP. A total of 106 participants after AP were included in this cross-sectional study and were grouped based on glycaemic status: new-onset prediabetes/diabetes after AP (NODAP), pre-existing prediabetes/type 2 diabetes (T2DM), and normoglycaemia after AP (NAP). Habitual intake of seven fat-soluble vitamins/vitamers and seven water-soluble vitamins were determined by the EPIC-Norfolk food frequency questionnaire. Multiple linear regression analyses were conducted using five statistical models built to adjust for covariates (age, sex, daily energy intake, visceral/subcutaneous fat volume ratio, smoking status, daily alcohol intake, aetiology of AP, number of AP episodes, cholecystectomy, and use of antidiabetic medications). In the NODAP group, three fat-soluble vitamins/vitamers (α-carotene, β-carotene, and total carotene) were significantly associated with HOMA-β. One water-soluble vitamin (vitamin B3) was also significantly associated with HOMA-β in the NODAP group. None of the studied vitamins were significantly associated with FPG or HOMA-IR in the NODAP group. Prospective longitudinal studies and randomised controlled trials are now warranted to investigate if the observed associations between vitamin/vitamer intake and NODAP are causal and to unveil the specific mechanisms underlying their involvement with NODAP. 相似文献