全文获取类型
收费全文 | 12857篇 |
免费 | 928篇 |
国内免费 | 353篇 |
学科分类
医药卫生 | 14138篇 |
出版年
2024年 | 13篇 |
2023年 | 190篇 |
2022年 | 298篇 |
2021年 | 481篇 |
2020年 | 551篇 |
2019年 | 476篇 |
2018年 | 463篇 |
2017年 | 490篇 |
2016年 | 470篇 |
2015年 | 497篇 |
2014年 | 919篇 |
2013年 | 970篇 |
2012年 | 782篇 |
2011年 | 834篇 |
2010年 | 683篇 |
2009年 | 647篇 |
2008年 | 635篇 |
2007年 | 616篇 |
2006年 | 562篇 |
2005年 | 500篇 |
2004年 | 384篇 |
2003年 | 390篇 |
2002年 | 283篇 |
2001年 | 242篇 |
2000年 | 191篇 |
1999年 | 145篇 |
1998年 | 145篇 |
1997年 | 149篇 |
1996年 | 115篇 |
1995年 | 134篇 |
1994年 | 119篇 |
1993年 | 89篇 |
1992年 | 83篇 |
1991年 | 67篇 |
1990年 | 65篇 |
1989年 | 66篇 |
1988年 | 57篇 |
1987年 | 30篇 |
1986年 | 47篇 |
1985年 | 52篇 |
1984年 | 50篇 |
1983年 | 19篇 |
1982年 | 31篇 |
1981年 | 28篇 |
1980年 | 22篇 |
1979年 | 23篇 |
1978年 | 7篇 |
1977年 | 10篇 |
1976年 | 9篇 |
1974年 | 3篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
71.
72.
COVID-19 is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which was first reported in Wuhan, China in December 2019, and is ongoing pandemic. While a majority of patients with SARS-CoV-2 infection shows asymptomatic or mild disease, hospitalized patients can develop critical condition, such as pneumonia, sepsis, and respiratory failure. Some cases deteriorate into sever systemic disease and multiorgan failure. Many patients of severe COVID-19 show hypercoagulable state and complicate with venous thromboembolism and atrial thrombosis. We herein reported a case of COVID-19 who developed cerebral venous thrombosis (CVT) co-incidence with pulmonary thromboembolism (PTE). A 56-year-old Japanese man was presented with fever and malaise and diagnosed with COVID-19. He was treated with ciclesonide and azithromycin, but his respiratory condition deteriorated. Thus, systemic corticosteroids and favipiravir were initiated and these treatments resulted in afebrile state, improving malaise and respiratory failure. However, he suddenly developed severe headache and vomiting with increased concentration of D-dimer. Brain CT and MRI showed typical images of CVT in the left transvers sinus and CT pulmonary angiography showed PE. Administration of unfractionated heparin followed by edoxaban treatment reduced the levels of D-dimer and improved his clinical presentation and thrombosis. Monitoring coagulopathy is important in COVID-19 patients and in case of venous thromboembolism, including cerebral venous system, appropriate anticoagulant therapy should be initiated. 相似文献
73.
目的探讨低分子肝素钙预防腰椎退行性疾病术后深静脉血栓形成(DVT)的有效性和安全性。方法回顾性分析广安市广安区人民医院68例腰椎退行性疾病患者的临床资料,术后均采用抗凝预防血栓形成,按照术后预防DVT所采用方式的不同分为对照组和低分子肝素钙组。分析比较2组患者术后引流量、切口愈合情况、DVT发生率、皮下瘀斑情况、血小板数值、凝血功能、D-二聚体。结果术后2组患者引流量、切口愈合情况、皮下瘀斑情况、凝血功能相关指标比较,差异无统计学意义(P>0.05)。术前和术后1、10 d 2组患者血小板数量的变化差异无统计学意义(P>0.05)。DVT发生率2组患者比较差异有统计学意义(P<0.05)。术前及术后1 d 2组患者D-二聚体比较,差异无统计学意义(P>0.05);术后10 d,对照组患者D-二聚体显著增加,2组比较差异有统计学意义(P<0.05)。结论腰椎退行性疾病术后使用低分子肝素钙进行抗凝,可以显著降低DVT的发生率,具有良好的安全性。 相似文献
74.
IntroductionDural venous sinus thrombosis is an uncommon, but significant sequela that may occur after resection of a cerebellopontine angle lesion. The natural history and management of this pathology has not been sufficiently studied.MethodsAll operative cases for cerebellopontine angle lesions performed in our local institution dating from 1 January 2005 to 30 June 2018 were retrospectively reviewed to identify patients who developed new post-operative dural venous sinus thrombosis. Patients who developed a significantly narrowed sinus without intrinsic thrombus were also identified. Progression of sinus thrombosis through time was followed, with comparisons made between complications amongst patients with and without a compromised sinus.ResultsOf the 126 patients, 20 were found to have new sinus thrombosis, with another 16 developing a critically narrowed sinus without intrinsic thrombus. These cases are significantly associated with translabyrinthine resection of acoustic schwannoma. 4 patients amongst the thrombosed group were commenced on additional therapeutic anticoagulation or antiplatelets, whilst the rest were observed. Based on available follow up imaging, 10/17 patients had significantly improved sinus thrombosis on serial imaging, including 8/14 amongst those not given additional anticoagulation. Patients with a compromised sinus demonstrated a higher rate of cerebrospinal fluid leak requiring blindsac procedures. When involving a dominant sinus, there is also an association of an increased requirement for permanent CSF diversion.ConclusionTherapeutic anticoagulation should be considered for symptomatic post-operative dural venous sinus thrombosis or if it involves a dominant sinus. Further prospective studies are warranted to better elucidate the risk-benefit justification of treatment for postoperative sinus thrombosis. 相似文献
75.
J. Montroy B. Hutton D.A. Fergusson A. Tinmouth L.T. Lavalle I. Cagiannos C. Morash A. Flaman R.H. Breau 《Current oncology (Toronto, Ont.)》2020,27(6):e560
BackgroundWhen used during surgery, antifibrinolytic hemostatic agents such as lysine analogues are effective at reducing blood loss and the need for transfusions. Despite proven efficacy, use of hemostatic agents remains low during some surgeries. Our objective was to explore surgeon opinions about, and use of lysine analogues in, oncologic surgeries at a large tertiary care academic institution.MethodsWe administered a survey to surgeons who perform high-transfusion-risk oncologic surgeries at a large academic hospital in Ottawa, Ontario. Design and distribution of the survey followed a modified Dillman method. To ensure that the survey questionnaire was relevant, clear, and concise, we performed informant interviews, cognitive interviews, and pilot-testing. The final survey consisted of 19 questions divided into 3 sections: respondent demographics, use of hemostatic agents, and potential clinical trial opinions.ResultsOf 28 surgeons, 24 (86%) participated. When asked to indicate the frequency of lysine analogue use, “never” accounted for 46% of the responses, and “rarely” (<10% of the time) accounted for 23% of the responses. Reasons for never using included “unfamiliar with benefits” and “prefer alternatives.” Fifteen surgeons (63%) felt that a trial was needed to demonstrate the efficacy and safety of lysine analogues in their cancer field.ConclusionsOur survey found that lysine analogues are infrequently used during oncologic surgeries at our institution. Many surgeons are unfamiliar with the benefits and side effects of lysine analogues and, alternatively, use topical hemostatic agents. Our results demonstrate that future trials exploring the efficacy and safety of lysine analogues in oncologic surgery are needed. 相似文献
76.
77.
78.
79.
80.
J.T. Deferm F. Baan R. Schreurs R. Willaert T. Maal G. Meijer 《International journal of oral and maxillofacial surgery》2021,50(1):38-42
Monitoring vascular perfusion of transferred tissue is essential in reconstructive surgery to recognize early flap failure. The aim of this study was to evaluate the ability of a digital surface scanner to detect vascular perfusion disorders through the monitoring of skin colour changes. A total of 160 surface scans of the forearm skin were performed with a TRIOS 3D scanner. Vascular compromise was simulated at different time-points by intermittent occlusion of the blood supply to the forearm skin (first the arterial blood supply and then the venous blood supply). Skin colour changes were examined according to the hue, saturation, and value colour scale. Colour differences were analysed with a paired t-test. Significant differences were observed between the colour of the normal skin and that of the vascular compromised skin (P < 0.01). The surface scanner could distinguish between arterial occlusion and venous congestion (P < 0.01). A digital surface scan is an objective, non-invasive tool to detect early vascular perfusion disorders of the skin. 相似文献