全文获取类型
收费全文 | 49626篇 |
免费 | 2995篇 |
国内免费 | 241篇 |
专业分类
耳鼻咽喉 | 505篇 |
儿科学 | 939篇 |
妇产科学 | 641篇 |
基础医学 | 6484篇 |
口腔科学 | 1096篇 |
临床医学 | 5204篇 |
内科学 | 10877篇 |
皮肤病学 | 998篇 |
神经病学 | 5738篇 |
特种医学 | 2520篇 |
外科学 | 8278篇 |
综合类 | 300篇 |
一般理论 | 13篇 |
预防医学 | 2289篇 |
眼科学 | 649篇 |
药学 | 2966篇 |
中国医学 | 70篇 |
肿瘤学 | 3295篇 |
出版年
2023年 | 432篇 |
2022年 | 696篇 |
2021年 | 1434篇 |
2020年 | 846篇 |
2019年 | 1281篇 |
2018年 | 1458篇 |
2017年 | 1134篇 |
2016年 | 1359篇 |
2015年 | 1569篇 |
2014年 | 1987篇 |
2013年 | 2447篇 |
2012年 | 3917篇 |
2011年 | 3962篇 |
2010年 | 2348篇 |
2009年 | 2114篇 |
2008年 | 3363篇 |
2007年 | 3449篇 |
2006年 | 3192篇 |
2005年 | 3133篇 |
2004年 | 2777篇 |
2003年 | 2650篇 |
2002年 | 2389篇 |
2001年 | 448篇 |
2000年 | 341篇 |
1999年 | 408篇 |
1998年 | 483篇 |
1997年 | 363篇 |
1996年 | 290篇 |
1995年 | 230篇 |
1994年 | 221篇 |
1993年 | 168篇 |
1992年 | 149篇 |
1991年 | 139篇 |
1990年 | 110篇 |
1989年 | 99篇 |
1988年 | 101篇 |
1987年 | 70篇 |
1986年 | 80篇 |
1985年 | 76篇 |
1984年 | 110篇 |
1983年 | 84篇 |
1982年 | 78篇 |
1981年 | 61篇 |
1980年 | 59篇 |
1979年 | 52篇 |
1978年 | 52篇 |
1977年 | 57篇 |
1976年 | 49篇 |
1975年 | 52篇 |
1974年 | 49篇 |
排序方式: 共有10000条查询结果,搜索用时 9 毫秒
11.
12.
Marie Warrer Petersen Tine Sylvest Meyhoff Marie Helleberg Maj-Brit Nørregaard Kjær Anders Granholm Carl Johan Steensen Hjortsø Thomas Steen Jensen Morten Hylander Møller Peter Buhl Hjortrup Mik Wetterslev Gitte Kingo Vesterlund Lene Russell Vibeke Lind Jørgensen Klaus Tjelle Thomas Benfield Charlotte Suppli Ulrik Anne Sofie Andreasen Thomas Mohr Morten H. Bestle Lone Musaeus Poulsen Mette Friberg Hitz Thomas Hildebrandt Lene Surland Knudsen Anders Møller Christoffer Grant Sølling Anne Craveiro Brøchner Bodil Steen Rasmussen Henrik Nielsen Steffen Christensen Thomas Strøm Maria Cronhjort Rebecka Rubenson Wahlin Stephan Jakob Luca Cioccari Balasubramanian Venkatesh Naomi Hammond Vivekanand Jha Sheila Nainan Myatra Christian Gluud Theis Lange Anders Perner 《Acta anaesthesiologica Scandinavica》2020,64(9):1365-1375
Introduction
Severe acute respiratory syndrome coronavirus-2 has caused a pandemic of coronavirus disease (COVID-19) with many patients developing hypoxic respiratory failure. Corticosteroids reduce the time on mechanical ventilation, length of stay in the intensive care unit and potentially also mortality in similar patient populations. However, corticosteroids have undesirable effects, including longer time to viral clearance. Clinical equipoise on the use of corticosteroids for COVID-19 exists.Methods
The COVID STEROID trial is an international, randomised, stratified, blinded clinical trial. We will allocate 1000 adult patients with COVID-19 receiving ≥10 L/min of oxygen or on mechanical ventilation to intravenous hydrocortisone 200 mg daily vs placebo (0.9% saline) for 7 days. The primary outcome is days alive without life support (ie mechanical ventilation, circulatory support, and renal replacement therapy) at day 28. Secondary outcomes are serious adverse reactions at day 14; days alive without life support at day 90; days alive and out of hospital at day 90; all-cause mortality at day 28, day 90, and 1 year; and health-related quality of life at 1 year. We will conduct the statistical analyses according to this protocol, including interim analyses for every 250 patients followed for 28 days. The primary outcome will be compared using the Kryger Jensen and Lange test in the intention to treat population and reported as differences in means and medians with 95% confidence intervals.Discussion
The COVID STEROID trial will provide important evidence to guide the use of corticosteroids in COVID-19 and severe hypoxia.13.
Low myocardial glucose uptake in Turner syndrome is unaffected by growth hormone: a randomized,placebo‐controlled FDG‐PET study 下载免费PDF全文
14.
Rodolphe Korichi Sophie Mac-Mary Ahmed Elkhyat Jean-Marie Sainthillier Pascal Ränsch Philippe Humbert Eric Viviant Germaine Gazano Christian Mahé 《Skin research and technology》2006,12(3):206-210
BACKGROUND/AIMS: The purpose of this work was to develop a new sensor for objective in vivo measurement of the cutaneous temperature based on micro-electro-mechanical systems (MEMS), and to compare these performances with those of a classical thermocouple. Research on this new sensor was carried out to allow the quantification of the thermal properties of the made-up skin. METHODS: Sixteen female subjects divided into two different age groups (18-35 and >50 years old) were recruited for this study. Several zones of the face and forearms were made up at random with foundations containing or not a thermoregulator raw material. The quantity of foundation applied on the skin was standardized and measurements were carried out first before make-up, and then 10 s and 5 min after make-up. The new sensor and the thermocouple were used successively on each zone. The cutaneous temperature was expressed in degrees celsius. RESULTS/CONCLUSION: The two systems are similar in terms of repeatability and reproducibility, with some differences in sensibility. The data measured by the MEMS sensor appear lower than those measured by the thermocouple. After make-up, the MEMS sensor detects a progressive increase of the temperature in time whereas the thermocouple detects a decrease. We found the same evolution on the face but in a more attenuated way. These results tend to show that the devices do not measure the same phenomenon. The thermocouple appears more sensitive to the thermal response of the made-up surface whereas the MEMS sensor appears more sensitive to the heat transfers in the interface between the skin and make-up. 相似文献
15.
16.
Anton H. Schwabegger Barbara DelFrari Christian Apprich 《European journal of plastic surgery》2006,28(8):534-536
Whereas decubitus ulcer in the back or hip region is a common entity in plegic or elderly patients, the occurrence in the lateral shoulder region is seldom seen. However, resulting from continuous lateral decubitus positioning or limited compliance by the patient, pressure sores may occur in almost any region of the body, but predominately, they arise in acral zones with underlying bone prominences. The deltoid area is such an anatomically critical region, especially if the underlying deltoid muscle is paralyzed. The transposition of a pedicled deltoid flap, slightly modified as a hatchet flap, is described for cover of a decubitus ulcer in the deltoid region in a paraplegic male. Although utilization of the deltoid flap as a free flap is an established procedure for selected indications [Russell et al. (1985) Extremity reconstruction using the free deltoid flap. Plast Reconstr Surg 76:586–595, Serafin D (1996) The deltoid flap. In: Serafin D (ed) Atlas of microsurgical composite tissue transplantation, chapter 19. Saunders, Philadelphia, PA, pp 153–159, Wang et al. (2003) The free deltoid flap: microscopic anatomy studies and clinical application to oral cavity reconstruction. Plast Reconstr Surg 112:404–411], transposition as a pedicled flap, to the best of our knowledge, has not been previously described in the available literature. 相似文献
17.
Nestin expression persists in astrocytes of organotypic slice cultures from rat cortex 总被引:11,自引:0,他引:11
Rainald Schmidt-Kastner Christian Humpel 《International journal of developmental neuroscience》2002,20(1):29-38
Nestin is an intermediate filament protein typical for neural precursor cells that is down-regulated in the post-natal rodent brain. Re-expression of nestin has been observed in reactive astrocytes after injury. In this study, organotypic slice cultures from rat cortex were examined for expression of nestin and glial fibrillary acidic protein between 2 and 8 weeks in culture. Immunoreactivity for nestin and glial fibrillary acidic protein was seen in astrocytes which persisted throughout the observation period. Immunofluorescence double labeling showed widespread co-localization of nestin and glial fibrillary acidic protein. Image analysis revealed that levels of nestin-immunoreactivity plateaued after 5 weeks in culture. By comparison nestin immunoreactivity was absent from glial cells of the cortex in mature rats. These immunohistochemical findings of a persistent expression of nestin in glial cells of organotypic slice culture of the rat cortex indicate a different time course of glial maturation in vitro. This difference could be related to the altered trophic stimulation in vitro; differences in neuronal maturation, activity or survival; slow degeneration of the vasculature; or intrinsic properties of astrocytes. 相似文献
18.
19.
20.
Oren N Gottfried Steven Chin H Christian Davidson William T Couldwell 《Skull base》2007,17(5):317-324
The authors present a case of amyloid infiltration involving the trigeminal nerve that mimicked a malignant cavernous sinus tumor with perineural tumor infiltration. A 64-year-old man presented with trigeminal nerve numbness. Imaging revealed a plaque-like enhancing lesion along the right lateral cavernous sinus extending anteriorly into Meckel's cave and involving the proximal V2 and V3 branches of the trigeminal nerve. The patient underwent an extradural frontotemporal craniotomy with middle fossa exposure of the cavernous sinus to diagnose and treat the presumed malignant cavernous sinus tumor. A reddish mass involving the lateral dural wall of the cavernous sinus was resected. The gasserian ganglion, V2, and V3, the latter of which was biopsied, were enlarged. Permanent histopathological studies showed microscopic eosinophilic, amorphous material, which stained positive for Congo red, and an absence of neoplastic cells. The final diagnosis was amyloidoma. Thus, amyloidomas can involve the trigeminal nerve or ganglia and should be considered in the differential diagnosis of a cavernous sinus lesion mimicking a tumor. Patients may have symptomatic improvement of trigeminal neuropathy with resection of the amyloidoma outside the nerve capsule that is compressing the nerve, while resection of the lesion from within the capsule may result in permanent trigeminal nerve dysfunction. 相似文献