全文获取类型
收费全文 | 265886篇 |
免费 | 22477篇 |
国内免费 | 9978篇 |
专业分类
耳鼻咽喉 | 2014篇 |
儿科学 | 5341篇 |
妇产科学 | 2846篇 |
基础医学 | 44932篇 |
口腔科学 | 4101篇 |
临床医学 | 20125篇 |
内科学 | 50703篇 |
皮肤病学 | 4283篇 |
神经病学 | 17671篇 |
特种医学 | 5264篇 |
外国民族医学 | 62篇 |
外科学 | 17244篇 |
综合类 | 35583篇 |
现状与发展 | 36篇 |
一般理论 | 6篇 |
预防医学 | 17720篇 |
眼科学 | 2726篇 |
药学 | 35923篇 |
75篇 | |
中国医学 | 11171篇 |
肿瘤学 | 20515篇 |
出版年
2024年 | 546篇 |
2023年 | 4385篇 |
2022年 | 9219篇 |
2021年 | 12967篇 |
2020年 | 10067篇 |
2019年 | 8661篇 |
2018年 | 8407篇 |
2017年 | 8528篇 |
2016年 | 8930篇 |
2015年 | 10296篇 |
2014年 | 15955篇 |
2013年 | 17465篇 |
2012年 | 15613篇 |
2011年 | 17818篇 |
2010年 | 14638篇 |
2009年 | 14595篇 |
2008年 | 14178篇 |
2007年 | 13301篇 |
2006年 | 11923篇 |
2005年 | 10472篇 |
2004年 | 8812篇 |
2003年 | 7800篇 |
2002年 | 6239篇 |
2001年 | 5361篇 |
2000年 | 4473篇 |
1999年 | 4045篇 |
1998年 | 3702篇 |
1997年 | 3488篇 |
1996年 | 3071篇 |
1995年 | 2757篇 |
1994年 | 2542篇 |
1993年 | 2190篇 |
1992年 | 1805篇 |
1991年 | 1648篇 |
1990年 | 1383篇 |
1989年 | 1179篇 |
1988年 | 1125篇 |
1987年 | 928篇 |
1986年 | 838篇 |
1985年 | 1316篇 |
1984年 | 1152篇 |
1983年 | 804篇 |
1982年 | 825篇 |
1981年 | 648篇 |
1980年 | 538篇 |
1979年 | 444篇 |
1978年 | 306篇 |
1977年 | 245篇 |
1976年 | 242篇 |
1975年 | 138篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
151.
HER2-positive breast cancer is an aggressive subtype identified in the 1980s. The development of therapies targeting the HER2 has improved outcomes. The current standard of care, established in 2012 is dual blockade with trastuzumab + pertuzumab as first-line followed by TDM-1 as second-line. Several suboptimal choices are available in third-line or more. In 2019 the presentation of several trials evaluating new drugs and regimens in third-line has re-opened questions about sequencing, treatment of triple positive disease and treatment choice after exposure to TDM-1. These include tucatinib, neratinib and trastuzumab-deruxtecan. Other agents – including other antibody drug conjugates and bispecific antibodies as well as combinations - will lead to further changes in coming years. Additionally, should the numerous putative biomarkers thus identified ever come into use at the clinic, choice of treatment and response evaluation may be substantially changed. 相似文献
152.
《Vaccine》2016,34(26):2948-2952
Herpes simplex virus type-1 (HSV-1) and -2 (HSV-2) are highly prevalent global pathogens which commonly cause recurrent oral and genital ulcerations. Less common but more serious complications include meningitis, encephalitis, neonatal infection, and keratitis. HSV-2 infection is a significant driver of the HIV epidemic, increasing the risk of HIV acquisition 3 fold. As current control strategies for genital HSV-2 infection, including antiviral therapy and condom use, are only partially effective, vaccines will be required to reduce infection. Both preventive and therapeutic vaccines for HSV-2 are being pursued and are in various stages of development. We will provide an overview of efforts to develop HSV-2 vaccines, including a discussion of the clinical need for an HSV vaccine, and status of research and development with an emphasis on recent insights from trials of vaccine candidates in clinical testing. In addition, we will touch upon aspects of HSV vaccine development relevant to low and middle income countries. 相似文献
153.
Flavia Temperilli Aldona Rina Isabella Massimi Anna Lisa Montemari Maria Luisa Guarino Alessandra Zicari 《Platelets》2015,26(8):783-787
Serum thromboxane-B2 (TxB2), together with arachidonic acid (AA)-induced platelet aggregation, are, at the moment, the most used tests to identify patients displaying high on-aspirin treatment platelet reactivity (HAPR). Both tests are specific for aspirin action on cyclooxygenase-1. While the correlation between serum TxB2 assay and clinical outcome is established, data are conflicting with regard to aspirin treatment and a possible association with AA-stimulated platelet markers and clinical outcome. To understand such discrepancy, we performed a retrospective study to compare both assays. We collected data from 132 patients receiving a daily dose of aspirin (100?mg/day) and data from 48 patients receiving aspirin on alternate days. All Patients who received a daily dose of aspirin were studied for AA-induced platelet aggregation together with serum TxB2 levels and AA-induced TxB2 formation was also studied in 71 patients out of entire population. Consistent with recommendations in the literature, we defined HAPR by setting a cut-off point at 3.1?ng/ml for serum levels of thromboxane B2 and 20% for AA-induced platelet aggregation. According to this cut-off point, we divided our overall population into two groups: (1) TxB2?<?3.1?ng/ml and (2) TxB2?>?3.1?ng/ml. We found low agreement between such tests to identify patients displaying HAPR. Our results show that AA-induced platelet aggregation >20% identify a smaller number of HAPR patients in comparison with TxB2. A good correlation between serum TxB2 and arachidonic acid-induced TxB2 production was found (r?=?0.76619). 相似文献
154.
Mehdi Karimi Shahri Hamid R. Niazkar Fariba Rad 《International journal of laboratory hematology》2021,43(2):160-168
In December 2019, a new type of coronavirus was detected for the first time in Wuhan, Hubei Province, China. According to the reported data, the emerging coronavirus has spread worldwide, infecting more than fifty-seven million individuals, leading to more than one million deaths. The current study aimed to review and discuss the hematological findings of COVID-19. Laboratory changes and hematologic abnormalities have been reported repeatedly in COVID-19 patients. WBC count and peripheral blood lymphocytes are normal or slightly reduced while these indicators may change with the progression of the disease. In addition, several studies demonstrated that decreased hemoglobin levels in COVID-19 patients were associated with the severity of the disease. Moreover, thrombocytopenia, which is reported in 5%-40% of patients, is known to be associated with poor prognosis of the disease. COVID-19 can present with various hematologic manifestations. In this regard, accurate evaluation of laboratory indicators at the beginning and during COVID-19 can help physicians to adjust appropriate treatment and provide special and prompt care for those in need. 相似文献
155.
156.
157.
158.
《Journal of vascular and interventional radiology : JVIR》2020,31(5):760-768.e1
PurposeTo investigate dynamic variables obtained from retrospective computed tomography angiography for ability to predict thoracic endovascular aortic repair (TEVAR) outcomes in patients with complicated type B aortic dissection (cTBAD).Materials and MethodsSeventy-nine patients with cTBAD who received TEVAR from March 2009 to June 2018 were retrospectively enrolled. Relative true lumen area (r-TLA) was computed at the level of tracheal bifurcation every 5% of all R-R intervals. Parameters that reflect the state of intimal motion were evaluated, including difference between maximum and minimum r-TLA (D-TLA) and true lumen collapse. The endpoints comprised early (≤ 30 days) and late (> 30 days) outcomes after intervention.ResultsOverall early mortality rate was 13.9% (11/79), and early adverse events rate was 24.1% (19/79). Patients who received TEVAR within 2 days of symptom onset demonstrated the worst outcomes. A longer time of r-TLA < 25% in 1 cardiac cycle (P = .049) and larger D-TLA (P < .001) were correlated to an increased early death. In addition, D-TLA was an independent predictor of early mortality. Area under the curve of D-TLA was 0.849 (95% confidence interval 0.730–0.967) for predicting early mortality and 0.742 (95% CI 0.611–0.873) for predicting early adverse events. Survival and event-free survival rates during follow-up were decreased in the D-TLA > 21.5% group compared with the D-TLA ≤ 21.5% group (all P < .001).ConclusionsLarger D-TLA is correlated with worse postoperative outcomes and might be a crucial parameter for future risk stratification in patients with cTBAD. 相似文献
159.
160.
Extensive research has indicated that miRNAs are crucial for the occurrence and progression of cancers. miR-451a, involved in breast cancer (BC), is one of the miRNAs. This study focused on the mechanism by which miR-451a regulates BC. The levels of miR-451a in BC tissues and cell lines were examined using quantitative real-time polymerase chain reaction (qRT-PCR). Kaplan‒Meier analysis showed that this was intimately related to the patient's overall survival rate. Functional experiments revealed the negative effects of miR-451a on the abilities of BC cells to multiply (tested by Cell Counting Kit-8), migrate (tested by wound healing assay), and invade (tested by Transwell assay) and its positive effects on apoptosis (tested by flow cytometry). Western blotting indicated that the expression of tumor-related proteins was affected by miR-451a. Moreover, in vivo experiments suggested that tumor growth was clearly restrained by an miR-451a agonist in a xenograft tumor model. Bioinformatic analysis indicated that miR-451a directly targeted Cyclin D2 (CCND2), as demonstrated by the luciferase reporter assay. An opposite change in the level of CCND2 and miR-451a in BC was indicated by qRT-PCR, western blotting, and immunohistochemistry. Subsequently, functional experiments and western blotting analysis confirmed that CCND2 accelerated BC progression, which was regulated by miR-451a. Cumulatively, research on miR-451a may be valuable for BC treatment. 相似文献