全文获取类型
收费全文 | 9971篇 |
免费 | 703篇 |
国内免费 | 236篇 |
专业分类
耳鼻咽喉 | 9篇 |
儿科学 | 292篇 |
妇产科学 | 128篇 |
基础医学 | 1175篇 |
口腔科学 | 96篇 |
临床医学 | 1298篇 |
内科学 | 1271篇 |
皮肤病学 | 42篇 |
神经病学 | 287篇 |
特种医学 | 219篇 |
外科学 | 973篇 |
综合类 | 1520篇 |
预防医学 | 794篇 |
眼科学 | 34篇 |
药学 | 1984篇 |
4篇 | |
中国医学 | 484篇 |
肿瘤学 | 300篇 |
出版年
2023年 | 117篇 |
2022年 | 172篇 |
2021年 | 347篇 |
2020年 | 284篇 |
2019年 | 307篇 |
2018年 | 288篇 |
2017年 | 296篇 |
2016年 | 329篇 |
2015年 | 341篇 |
2014年 | 618篇 |
2013年 | 736篇 |
2012年 | 603篇 |
2011年 | 619篇 |
2010年 | 482篇 |
2009年 | 407篇 |
2008年 | 467篇 |
2007年 | 452篇 |
2006年 | 346篇 |
2005年 | 311篇 |
2004年 | 279篇 |
2003年 | 289篇 |
2002年 | 222篇 |
2001年 | 201篇 |
2000年 | 146篇 |
1999年 | 140篇 |
1998年 | 135篇 |
1997年 | 120篇 |
1996年 | 113篇 |
1995年 | 109篇 |
1994年 | 106篇 |
1993年 | 104篇 |
1992年 | 89篇 |
1991年 | 84篇 |
1990年 | 93篇 |
1989年 | 82篇 |
1988年 | 71篇 |
1987年 | 58篇 |
1986年 | 45篇 |
1985年 | 174篇 |
1984年 | 122篇 |
1983年 | 118篇 |
1982年 | 112篇 |
1981年 | 94篇 |
1980年 | 56篇 |
1979年 | 47篇 |
1978年 | 37篇 |
1977年 | 26篇 |
1976年 | 22篇 |
1975年 | 26篇 |
1974年 | 19篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
1.
目的 分析微滴式数字PCR(droplet digital PCR, ddPCR)和实时荧光定量PCR(quantitative real-time PCR,qPCR)的核酸检测结果,比较两种方法检测各类样本的差异性,为改进新型冠状病毒核酸检测方案提供数据支持。 方法 利用ddPCR和qPCR技术对已经确诊的3例新型冠状病毒肺炎患者发病不同时间的全血、尿液、粪便共22份标本进行新型冠状病毒核酸检测。 结果 两种方法对人保守区域基因扩增结果一致:全血标本信号最强,尿液次之,粪便最少;ddPCR在1份全血,1份尿液,5份粪便中检出ORF-1ab和N基因的阳性微滴,qPCR仅在3份粪便中检出上述基因,漏检的3个标本基因拷贝数平均浓度为128 copies/ml;ddPCR在发病<5、5~15、>15 d的各类标本中都有检出,qPCR检出以中晚期为主;重症病例用ddPCR均可测到阳性微滴,qPCR检测的各类标本均为阴性;轻症病例的各类标本中qPCR只有粪便核酸检测阳性,ddPCR检出率高于qPCR。 结论 ddPCR可以有效克服qPCR 灵敏度不足的难题,是对qPCR 的有益补充,尤其是针对病毒载量比较低的血液、尿液和可疑的粪便或肛拭子标本,适用于早期感染的判断及患者治愈后出院诊断。 相似文献
2.
Frédéric Janvier Deborah Delaune Thomas Poyot Eric Valade Audrey Mérens Pierre E. Rollin Vincent Foissaud 《Emerging infectious diseases》2016,22(2):292-294
We evaluated RNA stability of Ebola virus in EDTA blood and urine samples collected from infected patients and stored in West Africa’s environmental conditions. In blood, RNA was stable for at least 18 days when initial cycle threshold values were <30, but in urine, RNA degradation occurred more quickly. 相似文献
3.
《药学学报(英文版)》2020,10(7):1294-1308
A great challenge in multi-targeting drug discovery is to identify drug-like lead compounds with therapeutic advantages over single target inhibitors and drug combinations. Inspired by our previous efforts in designing antitumor evodiamine derivatives, herein selective histone deacetylase 1 (HDAC1) and topoisomerase 2 (TOP2) dual inhibitors were successfully identified, which showed potent in vitro and in vivo antitumor potency. Particularly, compound 30a was orally active and possessed excellent in vivo antitumor activity in the HCT116 xenograft model (TGI = 75.2%, 150 mg/kg, p.o.) without significant toxicity, which was more potent than HDAC inhibitor vorinostat, TOP inhibitor evodiamine and their combination. Taken together, this study highlights the therapeutic advantages of evodiamine-based HDAC1/TOP2 dual inhibitors and provides valuable leads for the development of novel multi-targeting antitumor agents. 相似文献
4.
5.
6.
Matthew D. Li Katrina F. Chu Allegra DePietro Vincent Wu Eric Wehrenberg-Klee Omar Zurkiya Raymond W. Liu Suvranu Ganguli 《Journal of vascular and interventional radiology : JVIR》2019,30(3):314-319
Purpose
To evaluate the feasibility of a same-day yttrium-90 (90Y) radioembolization protocol with resin microspheres (including pretreatment angiography, lung shunt fraction [LSF] determination, and radioembolization) for the treatment of hepatocellular carcinoma (HCC) and liver metastases.Materials and Methods
All same-day radioembolization procedures performed over 1 y (February 2017 to January 2018) were included in this single-institutional retrospective analysis, in which 34 procedures were performed in 26 patients (median age, 63 y; 13 women), 19 with liver metastases and 7 with HCC. Yttrium-90 treatment activities were calculated by body surface area method. Tumor imaging response was assessed by Response Evaluation Criteria In Solid Tumors (RECIST) 1.1 for liver metastases and modified RECIST for HCC. Clinical side effects and adverse events were graded per Common Terminology Criteria for Adverse Events version 4.0.Results
All planned cases were technically successful, and no cases were canceled for elevated LSF or vascular anatomic reasons. Pretreatment angiography modified the planned 90Y treatment activity in 1 case in which vascular anatomy required a lobar-dose split into 2 for segmental infusions. In 18% of cases, patients were briefly admitted after the procedure for observation or symptom management. Imaging evaluation of initial efficacy at 1 month demonstrated partial response in 25% and stable disease in 67% of patients with liver metastases and partial/complete response in 43% and stable disease in 14% of patients with HCC. Grade ≥ 3 adverse events occurred in 6% of cases, with no systemic therapy–limiting toxicities. The mean total procedure time was 4.2 hours.Conclusions
A same-day 90Y radioembolization protocol with resin microspheres is feasible in select patients, which can expedite cancer therapy. 相似文献7.
《Journal of vascular and interventional radiology : JVIR》2020,31(7):1069-1073
This report describes a technique for measuring lung shunt fraction (LSF) twice in a single session during planning arteriography for radioembolization using low and standard dose technetium-99m macroaggregated albumin (99mTc-MAA). A patient with a 16.0 cm hepatocellular carcinoma and LSF of 70% was treated with lenvatinib for 4 weeks. Planning arteriography with administration of 0.5 millicuries of 99mTc-MAA was then performed. Arterial access was maintained while the LSF was calculated, which was persistently elevated at 54%. Embolization of arteriovenous shunts was performed during the same session and 5.0 millicuries of 99mTc-MAA were administered. The repeat LSF was 29%. Successful radioembolization was subsequently performed. 相似文献
8.
目的 评价缺血修饰性白蛋白(ischemia modified albumin,IMA)对急性缺血性胸痛(ICP)的早期诊断价值。方法 时206例发病〈12h、表现为急性胸痛的患者立即行12导联心电图(ECG)检查,并抽血进行IMA、肌钙蛋白I(cTnI)、肌酸激酶同工酶MB(CK-MB)测定。将ECG、IMA、cTnI、CK-MB的结果单独或结合与最终诊断为非缺血性胸痛(NICP)及ICP的相互关系进行比较。结果 最后诊断为ICP98例,NICP108例,ICP发病〈3h和3-6h组IMA水平明显升高,与NICP组比较差异有统计学意义(P〈0.001);ICP发病〉6h组IMA水平与NICP组比较差异无统计学意义(P〉0.05)。IMA诊断发病〈3hICP的敏感性和阴性预测值(NPV)为89.1%和88.8%,明显高于ECG、cTnI和CK-MB,四者结合为97.6%和96.9%;IMA诊断发病3~6hICP的敏感性和NPV为71.7%和74.5%,也高于ECG、cTnI、CK-MB,四者结合为95.5%和94.2%;但IMA对于发病〉6h的ICP则无诊断作用。结论 IMA是诊断ICP的早期敏感生化指标,对于发病〈6h(尤其是〈3h)的ICP诊断具有较高的敏感性和NPV,优于ECG、CK-MB、cTnI;将IMA与其他指标结合,可进一步提高对ICP的诊断价值。 相似文献
9.
Nobuhiko Joki Hiroki Hase Yuri Tanaka Yasunori Takahashi Tomokatsu Saijyo Hiroyaou Ishikawa Yoji Inishi Yoshihiko Imamura Hisao Hara Taro Tsunoda Masato Nakamura 《Nephrology, dialysis, transplantation》2006,21(6):1633-1639
BACKGROUND: In patients with chronic kidney disease (CKD), although strong associations have been observed between malnutrition and atherosclerosis, the relationship between serum albumin concentration and angiographic changes of coronary artery disease (CAD) remains poorly explored. The goal of the present study was, in patients with CKD, to clarify the relationship between the angiographic severity of CAD and serum albumin concentration reflecting either inflammation or nutrition or both. METHODS: In this study, 100 end-stage renal disease (ESRD) patients were enrolled, who commenced long-term dialysis therapy at our hospital and underwent coronary angiography within 3 months of the first haemodialysis (HD) session. Mean age was 63+/-11 years, 20% of the subjects were female and 62% had diabetes. Severity of CAD was evaluated in terms of (i) number of vessels exhibiting CAD (>or=75% stenosis) and (ii) Gensini score (GS). Clinical characteristics and laboratory findings were recorded at initiation of long-term HD therapy. We then evaluated a possible association with the presence and degree of CAD. RESULTS: Sixty-four patients exhibited signs of CAD. Forty-one among them (64%) had multivessel disease. On univariate logistic regression analysis, age, diabetes and hypoalbuminaemia were significantly associated with multivessel CAD. Univariate linear regression analysis demonstrated a positive correlation of age and diabetes with GS, and an inverse correlation of BMI and serum albumin level with GS. Stepwise regression analysis showed age and serum albumin level to be independently associated with multivessel CAD and GS. The ROC curves demonstrated best cut-off levels of age and albumin for predicting multivessel CAD to be 70 years and 3.15 g/dl, respectively. CONCLUSION: Hypoalbuminaemia at the initiation of dialysis is an important predictor of advanced CAD, particularly in male and in diabetic patients. It may reflect mainly a state of inflammation. However, malnutrition as a confounding factor cannot be entirely excluded. 相似文献
10.
对血清蛋白白球比值参考范围的修改及其临床应用 总被引:1,自引:0,他引:1
李学军 《实用医药杂志(山东)》2006,23(1):34-35
目的探讨血清蛋白白球比值(A/G)的参考范围和A/G在计算过程中产生的误差对临床应用的影响。方法①选取健康查体人员统计其A/G参考范围;②从理论上分析A/G计算误差的存在。结果①以统计结果的2s置信区间作为A/G的参考范围是1.1~2.2;②A/G计算值的误差会远大于相应总蛋白和白蛋白的测定误差。结论A/G较合适的参考范围为1.1~2.2,并且在临床应用中仍可根据实际情况降低其范围的下限。 相似文献