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61.
Akansha Mehta Khaoula Karbouche Jozef Kraxner Hamada Elsayed Duan Galusek Enrico Bernardo 《Materials》2022,15(11)
The present COVID-19 emergency has dramatically increased the demand for pharmaceutical containers, especially vials. End-of-life containers, however, cannot be easily recycled in the manufacturing of new articles. This paper presents some strategies for upcycling of pharmaceutical glass into various porous ceramics. Suspensions of a fine glass powder (70 vol%) are used as a starting material. Highly uniform cellular structures may be easily prepared by vigorous mechanical stirring of partially gelified suspensions with added surfactant, followed by drying and firing at 550–650 °C. Stabilization of the cellular structures at temperatures as low as the glass transition temperature (Tg) of the used glass is facilitated by thermal decomposition of the gel phase, instead of viscous flow sintering of glass. This finding enabled the preparation of glass membranes (∼78 vol% open porosity), by direct firing of hardened suspensions, avoiding any surfactant addition and mechanical stirring. The powders obtained by crushing of hardened suspensions, even in unfired state, may be used as a low-cost sorbent for dye removal. 相似文献
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63.
Katrin Schmelz Samuel Bowles 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(13)
COVID-19 vaccination rates slowed in many countries during the second half of 2021, along with the emergence of vocal opposition, particularly to mandated vaccinations. Who are those resisting vaccination? Under what conditions do they change their minds? Our three-wave representative panel survey from Germany allows us to estimate the dynamics of vaccine opposition, providing the following answers. Without mandates, it may be difficult to reach and to sustain the near-universal level of repeated vaccinations apparently required to contain the Delta, Omicron, and likely subsequent variants. But mandates substantially increase opposition to vaccination. We find that few were opposed to voluntary vaccination in all three waves of the survey. They are just 3.3% of our panel, a number that we demonstrate is unlikely to be the result of response error. In contrast, the fraction consistently opposed to enforced vaccinations is 16.5%. Under both policies, those consistently opposed and those switching from opposition to supporting vaccination are sociodemographically virtually indistinguishable from other Germans. Thus, the mechanisms accounting for the dynamics of vaccine attitudes may apply generally across societal groups. What differentiates them from others are their beliefs about vaccination effectiveness, their trust in public institutions, and whether they perceive enforced vaccination as a restriction on their freedom. We find that changing these beliefs is both possible and necessary to increase vaccine willingness, even in the case of mandates. An inference is that well-designed policies of persuasion and enforcement will be complementary, not alternatives.The challenge of the first half-year of most COVID-19 vaccination campaigns was the supply of vaccines, not demand for them. It then appeared that, once vaccines were widely available, vaccination rates would approach the two-thirds level initially thought to be sufficient to control the pandemic. But the Delta and then Omicron variants along with substantial and persistent reported opposition to vaccination have raised doubts about whether vaccine willingness will be sufficient. In response, by the end of 2021, vaccination mandates were being widely adopted by governments, businesses, and educational institutions, and universal mandates were being considered and implemented (1–8).The appropriate strategies for raising vaccination rates depend on the target rate, on how many are unlikely to be vaccinated willingly in a sufficiently timely manner, on the conditions under which opponents change their minds, and on the effect of the policies themselves on vaccination preferences. Our study sheds light on the behavioral side of this evaluation. 相似文献
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66.
Katrin Hartmann 《Viruses》2012,4(11):2684-2710
Feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) are retroviruses with global impact on the health of domestic cats. The two viruses differ in their potential to cause disease. FeLV is more pathogenic, and was long considered to be responsible for more clinical syndromes than any other agent in cats. FeLV can cause tumors (mainly lymphoma), bone marrow suppression syndromes (mainly anemia), and lead to secondary infectious diseases caused by suppressive effects of the virus on bone marrow and the immune system. Today, FeLV is less commonly diagnosed than in the previous 20 years; prevalence has been decreasing in most countries. However, FeLV importance may be underestimated as it has been shown that regressively infected cats (that are negative in routinely used FeLV tests) also can develop clinical signs. FIV can cause an acquired immunodeficiency syndrome that increases the risk of opportunistic infections, neurological diseases, and tumors. In most naturally infected cats, however, FIV itself does not cause severe clinical signs, and FIV-infected cats may live many years without any health problems. This article provides a review of clinical syndromes in progressively and regressively FeLV-infected cats as well as in FIV-infected cats. 相似文献
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68.
Filip F Brănişteanu D Popovici I Jerca L Topoliceanu F Mancaş G Sărmăşan V Vartolomei M Jerca O Busuioc D 《Revista medico-chirurgical?? a Societ????ii de Medici ??i Naturali??ti din Ia??i》1999,103(3-4):153-157
This study aims at assessing the ability of asthma patients to defend themselves against the noxious effects of oxidative stress, known being the inflammatory nature of this disorder. As the anti-radical defence ability of the body is reflected by the antioxidative potential of blood and tissues, our study was based on the determination of the activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and CAT/SOD and GPx/SOD ratios in the blood. Except for SOD, the activity of which was lower in asthma patients by -34.08%, CAT and GPx had values increased by +32.18%, respectively, with a resulting increase of CAT/SOD and GPx/SOD ratios. Our data, demonstrating a change in per-oxidants/antioxidants balance in favour of the first ones, seem to suggest that in the treatment of bronchial asthma the association of some compounds with antioxidants effects would be beneficial. 相似文献
69.
Claudia Sikorski Melanie Luppa Katrin Dame Elmar Brähler Tatjana Schütz Edward Shang Hans-Helmut König Steffi G. Riedel-Heller 《Obesity surgery》2013,23(3):338-345
Background
Prevalence rates of obesity are still rising. Weight loss surgery (WLS) is the most invasive but also most effective treatment option when behavioral modification has failed. Research indicates that health care professionals hold ambivalent views on bariatric surgery, while views of the general public have not yet been investigated.Methods
In a German representative sample of n?=?3,003 respondents in a computer-assisted telephone interview, n?=?1,008 persons were interviewed on their views of the effectiveness of bariatric surgery and other interventions for obesity. Also, willingness to recommend a treatment was assessed.Results
Lifestyle-based interventions were viewed as most effective in terms of weight loss. About 50 % of the population stated that WLS is “very effective” while still a quarter of respondents did not ascribe effectiveness to WLS. Higher age was associated with lower expectations of effectiveness while higher stigmatizing attitudes and genetic attributes for obesity were associated with higher expectations of effectiveness. Seventy-two percent would not recommend WLS or undergo it, if applicable, themselves. Higher educated respondents and those that viewed WLS as effective were more likely to recommend WLS.Conclusions
The German general public seems to be rather cautious regarding bariatric surgery. It may be assumed that false beliefs on the effectiveness and risk patterns of bariatric surgery are still very common, despite rising surgery numbers. Our results further emphasize the need for providing evidence-based information on bariatric surgery to the general public. 相似文献70.
创伤及内毒素对大鼠肠屏障功能的损害 总被引:5,自引:3,他引:5
目的 探讨创伤合并感染对机体肠屏障功能的损害作用。方法 随机、对照性实验。雄性成年SD大鼠 3 5只 ,分为对照组 (Con)及肠内营养 (EN)、静脉营养 (PN)和脓血症组 (Sep)。后三组做成静脉营养模型 ,施以不同损害刺激。结果 Sep组小肠黏膜损害最重 ,内毒素导致EN、Sep组血浆中一氧化氮升高 ,分别为 10 3 .3 9、113 .3 3 μmol/L ;Sep组小肠通透性和细菌易位率增加 ,分别为 4.0 0 %和 83 .3 3 %。EN组肠屏障损害显著减轻。结论 静脉营养 1周导致大鼠小肠黏膜萎缩 ,肠通透性增加 ;内毒素加重了创伤大鼠肠屏障功能损害 ,可能与体内一氧化氮产生增多有关 ;肠道喂养显著减轻了肠屏障功能损伤 相似文献