全文获取类型
收费全文 | 89632篇 |
免费 | 9014篇 |
国内免费 | 7285篇 |
专业分类
耳鼻咽喉 | 653篇 |
儿科学 | 828篇 |
妇产科学 | 986篇 |
基础医学 | 10769篇 |
口腔科学 | 1601篇 |
临床医学 | 12987篇 |
内科学 | 13141篇 |
皮肤病学 | 727篇 |
神经病学 | 5308篇 |
特种医学 | 3194篇 |
外国民族医学 | 56篇 |
外科学 | 8319篇 |
综合类 | 15394篇 |
现状与发展 | 22篇 |
一般理论 | 13篇 |
预防医学 | 5805篇 |
眼科学 | 2942篇 |
药学 | 9264篇 |
103篇 | |
中国医学 | 5846篇 |
肿瘤学 | 7973篇 |
出版年
2024年 | 313篇 |
2023年 | 1519篇 |
2022年 | 4294篇 |
2021年 | 5171篇 |
2020年 | 3947篇 |
2019年 | 3212篇 |
2018年 | 3431篇 |
2017年 | 2888篇 |
2016年 | 2830篇 |
2015年 | 4302篇 |
2014年 | 5295篇 |
2013年 | 4477篇 |
2012年 | 6587篇 |
2011年 | 7633篇 |
2010年 | 4579篇 |
2009年 | 3596篇 |
2008年 | 4600篇 |
2007年 | 4458篇 |
2006年 | 4642篇 |
2005年 | 4656篇 |
2004年 | 2750篇 |
2003年 | 2675篇 |
2002年 | 2234篇 |
2001年 | 1943篇 |
2000年 | 2067篇 |
1999年 | 2178篇 |
1998年 | 1448篇 |
1997年 | 1374篇 |
1996年 | 1107篇 |
1995年 | 1026篇 |
1994年 | 848篇 |
1993年 | 536篇 |
1992年 | 604篇 |
1991年 | 514篇 |
1990年 | 466篇 |
1989年 | 426篇 |
1988年 | 348篇 |
1987年 | 297篇 |
1986年 | 228篇 |
1985年 | 178篇 |
1984年 | 81篇 |
1983年 | 50篇 |
1982年 | 41篇 |
1981年 | 36篇 |
1980年 | 24篇 |
1979年 | 21篇 |
1964年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
941.
利用紫外分光光度计对二氯二茂钛进行含量测定。回归方程为 :Y =0 9881X - 0 90 90× 10 -3(Y :吸光度 ;X :浓度 ,mg/L) ,相关系数r=0 9999,线性范围为 13 .6~ 81.6mg/L。模拟试验 3份 ,回收率为 98 4 5 %~ 10 1 3 3 % ,相对标准偏差为 0 14 %~ 0 3 3 %。本实验研究了原料药二氯二茂钛的稳定性 ,结果表明不同的湿度、温度等条件对二氯二茂钛的稳定性有一定影响 相似文献
942.
目的研究GDM对母婴的影响。方法对112例GDM孕妇和112例健康孕妇的妊娠结局进行分析。采用11配对病例—对照研究,配对的条件是孕妇年龄相近(±2),同年同月同医院分娩。结果GDM孕妇手术分娩率、早产率、妊娠高血压综合征和巨大儿发生率都较对照组高。GDM的及早诊断和及时治疗可使巨大儿发生率降低。与新生儿病率有关的因素是GDM的严重程度、血糖控制情况及巨大儿。结论早期诊断GDM及控制血糖是减少妇婴并发症的关键。 相似文献
943.
目的 为在东北地区开发饲育高原鼠兔提供基础资料。方法 在室内人工饲育条件下,对高原鼠兔的外观、习性及食性等方面进行观察与研究。结果 高原鼠兔具有体型小、性情温顺、繁殖力强及饲料简单等特点,对低质饲料的利用率和对植物纤维的需求较高,超过家兔,更易饲养,结论 高原鼠兔在东北地区室内饲养是可以适应的。将高原鼠兔作为实验动物,有利于节省饲养空间和经费。 相似文献
944.
肝性脑病的现代护理 总被引:6,自引:0,他引:6
肝性脑病 (Hepatic Enoephalopathy,HE)是内科常见的危重症之一。据文献报道 :肝性脑病的发生主要是由于肝功能损害严重及广泛的侧枝循环形成 ,来自肠道毒物直接进入体循环 [1 ] ,引起中枢神经系统代谢紊乱为特点并出现意识行为改变或昏迷的临床综合征。1 病因与发病护理1.1 病因国内外资料表明肝性脑病绝大多数是由于慢性病所致 ,主要疾病为肝硬化 ,次要原因为重症肝炎及肝癌 [2 ]。前者不仅为晚期肝细胞功能衰竭所致 ,也可因侧枝循环而导致分流性脑病 ,严重的中毒性肝炎、妊娠急性脂肪肝及 Reye综合征均可发生肝性脑病。1.2 诱因肝性… 相似文献
945.
目的:采用HPLC法测定氧氟沙星注射液的含量。方法:采用HPLC法,以氧氟沙星为对照品,检测波长为293nm,甲醇:枸缘酸(0.05mol/L):乙腈:醋酸铵溶液(0.5mol/L):10g/L磷酸(100:75:22:1:2)为流动相。结果:氧氟沙星的平均回收率为97.44%、RSD为1.83%。结论:本法结果准确,精密度、重现性均好,可作为该制剂的含量测定。 相似文献
946.
目的建立一种新的微柱凝胶抗球蛋白实验诊断新生儿溶血病。方法采用微柱凝胶抗球蛋白实验与试管抗球蛋白实验同时平行做三项实验:直接抗球蛋白实验、游离IgG抗体测定、放散实验。结果两法检测126例(Rh(D)均为阳性)疑为新生儿溶血病标本,阳性率分别为76例(60.3%)、50例(39.7%)。结论该法具有操作简单、方便、标本用量少、结果易判定、敏感性高、特异性强、结果可较长时间保存等优点。与临床诊断符合率高达98%,为新生儿溶血病提供实验室可靠诊断依据。 相似文献
947.
Chao Wang Bei Liu Sihui Zhang Ninghua Huang Tianshuo Zhao Qing-Bin Lu Fuqiang Cui 《Journal of medical virology》2023,95(1):e28118
We aim to evaluate the evolution differences in the incidence and case fatality rate (CFR) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta and Omicron variants. The average incidence and CFRs were described between different countries. A gamma generalized linear mixed model (GLMM) was used to compare the CFRs of Delta and Omicron variants based on vaccination coverage. Totally, 50 countries were included for analyses. The incidence of coronavirus disease 2019 (COVID-19) ranged from 0.16/100,000 to 82.95/100,000 during the Delta period and 0.03/100,000 to 440.88/100,000 during the Omicron period. The median CFRs were 8.56 (interquartile range [IQR]: 4.76–18.39) during the Delta period and 3.04 (IQR: 1.87–7.48) during the Omicron period, respectively. A total of 47 out of 50 countries showed decreased CFRs of the Omicron variant with the rate ratio ranging from 0.02 (95% confidence interval [CI]: 0.01–0.03) (in Cambodia) to 0.97 (95% CI: 0.87–1.08) (in Ireland). Gamma GLMM analysis showed that the decreased CFR was largely a result of the decreased pathogenicity of Omicron besides the increased vaccination coverage. The Omicron variant shows a higher incidence but a lower CFR around the world as a whole, which is mainly a result of the decreased pathogenicity by SARS-CoV-2's mutation, while the vaccination against SARS-CoV-2 still acts as a valuable measure in preventing people from death. 相似文献
948.
Ke Li Jin Shi Xin Liu Michael P. Ward Zengliang Wang Rui Liu Zheng Zhao Yun Yin Yuanhua Liu Jie Hong Jiaqi Huang Xi Chen Zhijie Zhang 《Journal of medical virology》2023,95(1):e28341
The Omicron variant has become the dominant COVID-19 variant worldwide due to its rapid and cryptic spread. Therefore, successful early warning is of great importance to be able to control epidemics in their early phase, before developing into large outbreaks. COVID-19-related Baidu search index, which reflects human behavior to a certain degree, was used to retrospectively detect the warning signs for Omicron variant outbreaks in China in 2022. The characteristics and effects of warning signs were analyzed in detail. We detected the presence of early warning signs (both high and low thresholds) and found that these occurred 4–7 days earlier than traditional epidemiological surveillance and >20 days earlier than the implementation of the local “lockdown” policy. Compared with the “high threshold” warning, the early warning effect of the “low threshold” is also vital because it indicates a negligence about epidemic prevention and control. However, there is obvious heterogeneity in the optimal threshold for detecting early warning signs and their distribution in different cities. Multi-source and multi-point early warning systems should be established via combining internet-based big data in the future to conduct effective and early real-time warning. This would create precious time for the early control of COVID-19 outbreaks. 相似文献
949.
Fan Wu Yue Yuan Yanjun Li Di Yin Bing Lang Yangguo Zhao Xueying Fan Huachun Zou Chunhuan Zhang Xiangyue Zeng Caijun Sun 《Journal of medical virology》2023,95(1):e28227
Compared with the nucleic acid amplification test (NATT), the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) rapid antigen self-testing (RAST) has advantages in speed and convenience. However, little is known about people's acceptance and influencing factors for SARS-CoV-2 RAST. A cross-sectional study was conducted from April 21 to 30, 2022 in China. The χ2 test and multivariate logistic regressions were used to identify the influencing factors. The structural equation model was used to test the extended protective motivation theory (PMT) model hypotheses. Among the total of 5107 participants, 62.5% were willing to accept the SARS-CoV-2 RAST. There were significant differences in acceptance among different residences (p < 0.001), educational level (p < 0.001), occupation (p < 0.001), monthly income (p < 0.001), travel frequency (p < 0.05), and feelings about NATT (p < 0.001). Response efficacy (β = 0.05; p = 0.025) and self-efficacy (β = 0.84; p < 0.001) had a positive effect, while response cost showed a negative effect (β = −0.07; p < 0.001). The public's major concerns about SARS-CoV-2 RAST are its reliability, testing method, price, and authority. Overall, a moderate intention to use SARS-CoV-2 RAST was found among the Chinese population. The extended PMT can be used for the prediction of intention to accept the RAST. We need to take measures to increase people's acceptance of SARS-CoV-2 RAST. 相似文献
950.