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991.
四川省一起伴中毒性休克综合征的人感染猪链球菌2型暴发 总被引:24,自引:2,他引:24
杨维中 余宏杰 景怀琦 徐建国 陈志海 祝小平 汪华 刘学成 王世文 刘伦光 祖荣强 罗隆泽 向妮娟 刘红露 钟文君 刘莉 孟玲 袁珩 高永军 杜化茂 欧阳宾 叶长芸 金冬 吕强 崔志刚 黄燕 张守印 安向东 黄婷 周兴余 冯燎 庞启迪 舒跃龙 王宇 《中华流行病学杂志》2006,27(3):185-191
目的 调查2005年7月中旬四川省资阳市一家医院报告5例以败血症休克为主要临床表现的聚集性病例的病因。方法 建立了病例主动发现、报告的加强监测系统,根据病例的流行病学暴露史和临床表现进行临床诊断;采集患者标本进行细菌分离培养和生化反应鉴定,应用PCR方法对猪链球菌2型的种属和毒力基因进行检测和序列测定;与当地往年报告的流行性脑脊髓膜炎发病数进行比较。结果 2005年6月10日至8月21日,四川省共报告了68例实验室确诊人感染猪链球菌病例,发病前都有屠宰、洗切、加工等病(死)猪的直接暴露史。其中26例(38%)表现为中毒性休克综合征,15例(58%)死亡。其他病例临床表现为轻型败血症或脑膜炎。分离菌株应用PCR方法检测猪链球菌2型的种属和毒力基因(tuf、16S rRNA、cps2J、mrp、sly、ef)均为阳性。同期还报告了136例有相似暴露史,但缺乏实验室确诊依据的临床诊断病例。结论 证实该起发生在四川省部分农村地区直接暴露于病(死)猪后的疾病为猪链球菌2型感染暴发。推测这种罕见的、表现为高病死率的中毒性休克综合征可能是由于感染某种高致病性菌株循环所致。 相似文献
992.
993.
急性期精神分裂症返回抑制时间进程的初步研究 总被引:1,自引:0,他引:1
目的探讨急性期精神分裂症返回抑制时间进程的基本属性。方法30例健康志愿者及41例符合ICD-10精神分裂症诊断标准的急性期患者分别接受线索-靶子实验。靶子位置的2个水平分别为线索化位置和非线索化位置。线索开始呈现到靶子开始呈现的时间间隔(stimulus onsetasynchrony,SOA)的9个水平分别为300ms,400ms,500ms,600ms,700ms,800ms,1200ms,1500ms和2500ms。记录被试的反应时和错误率。结果(1)经重复测量方差分析,发现分组因素的主效应显著(P=0.000),健康对照组的平均反应时(365ms)短于精神分裂症患者的平均反应时(521ms)。靶子位置的主效应显著(P=0.000),靶子在线索化位置的反应时(458ms)长于非线索化位置的反应时(428ms)。SOA主效应不显著(P=0.338)。分组和SOA之间、分组和靶子位置之间、SOA和靶子位置之间以及分组、SOA和靶子位置之间的交互作用均不显著(P均〉0.05)。(2)健康对照组在所有SOA水平上靶子在线索化位置的反应时均长于非线索化位置的反应时,差异均达非常显著性(P均〈0.01)。(3)精神分裂症患者在所有SOA水平上靶子在线索化位置的反应时均长于非线索化位置的反应时,其中SOA为400ms,700ms和2500ms时,差异有显著性(P〈0.05);SOA为600ms,800ms,1200ms和1500ms时,差异有非常显著性(P〈0.01);而SOA为300ms和500ms时,差异无显著性(P〉0.05)。结论正常人自SOA300ms以后就出现稳定的返回抑制,而急性期精神分裂症患者的返回抑制延迟出现,SOA600ms以后出现稳定的返回抑制。 相似文献
994.
Environmentally persistent free radicals (EPFRs) in biochars have the ability of catalytic formation of reactive oxygen species, which may pose potential oxidative stresses to eco-environment and human health. Therefore, comprehending the formation and characteristics of EPFRs in biochars is important for their further applications. In this study, the woody lignocellulosic biomass (wood chips, pine needle and barks), non-woody lignocellulosic biomass (rice husk, corn stover, and duckweed), and non-lignocellulosic biomass (anaerobically digested sludge) were selected as biomass feedstock to prepare biochars under different pyrolysis temperatures (200–700 °C). The impact of biomass feedstock on formation of biochar-bound EPFRs was systematically compared. Elemental compositions and atomic ratios of H/C and O/C varied greatly among different biomass feedstocks and the subsequently resulting biochars. EPFRs in biochars derived from the studied lignocellulosic biomass have similar levels of spin concentrations (1018–1019 spins per g) except for lower EPFRs in biochars under 200 and 700 °C; however, sludge-based biochars, a typical non-lignocellulosic-biomass-based biochar, have much lower EPFRs (1016 spins per g) than lignocellulosic-biomass-based biochars under all the studied pyrolysis temperatures. Values of g factors ranged from 2.0025 to 2.0042 and line width was in the range of 2.15–11.3 for EPFRs in the resulting biochars. Spin concentrations of biochar-bound EPFRs increased with the increasing pyrolysis temperatures from 200 to 500 °C, and then decreased rapidly from 500 to 700 °C and oxygen-centered radicals shifted to carbon-centered radicals with the increasing pyrolysis temperatures from 200 to 700 °C for all the studied biomass feedstock. 300–500 °C was the appropriate pyrolysis temperature range for higher levels of spin concentrations of biochar-bound EPFRs. Moreover, EPFRs'' concentrations had significantly positive correlation with C contents and weak or none correlation with contents of transition metals. Overall, different types of biomass feedstock have significant impact on the formation of EPFRs in the resulting biochars.Environmentally persistent free radicals (EPFRs) in biochars have the ability of catalytic formation of reactive oxygen species, which may pose potential oxidative stresses to eco-environment and human health. 相似文献
995.
996.
Yang Dai Jingcao Huang Pu Kuang Yiguo Hu Qiang Zeng Wanhua Zhang He Li Fangfang Wang Tingting Guo Dan Zhang Dongni Yi Yuhuan Zheng Ting Liu 《American journal of cancer research》2022,12(6):2817
Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) is a high-risk disease subtype with a dismal prognosis. Inhibiting BCR-ABL kinase alone is insufficient to eradicate Ph+ALL clones, and alternative BCR-ABL-dependent and -independent pathways need to be targeted as an effective strategy. Our study revealed that the combination of dasatinib and interferon-α showed synergistic activity against Ph+ALL, inducing mitochondrial dysfunction and causing necrosis-like cell lysis. Mechanistic studies showed that the induced cell death was caspase-3-independent. Canonical necroptosis signals, such as RIP1 and MLKL, were not activated; instead, the pyroptosis executor Gasdermin D was upregulated expression and activated. The expression levels of extracellular ATP and IL-1β were also upregulated, both of which are markers of pyroptotic cell death. In a murine Ph+ALL model, the dual drug treatment prolonged the survival of tumor-bearing mice. More importantly, we incorporated the dual drugs to maintenance therapy in 39 patients who were unfit for allogeneic stem cell transplantation (allo-HSCT). The median follow-up was 28.5 months, the 4-year disease-free survival and overall survival rates were 52.2% and 65.2%, respectively. Our data suggest that the combination of dasatinib and interferon-α has potential synergistic activity against Ph+ALL and shows promise as a maintenance therapy for Ph+ALL patients who are unfit for allo-HSCT. 相似文献
997.
998.
Ke Li Shuping Sun Zhanyou Xue Sufen Chen Chunyang Ju Dongmei Hu Xiaoyu Gao Yanhong Wang Dan Wang Jianjun Chen Li Li Jing Liu Mingjie Zhang Zhihua Jia Xun Han Huanxian Liu Mianwang He Wei Zhao Zihua Gong Shuhua Zhang Xiaoxue Lin Yingyuan Liu Shengshu Wang Shengyuan Yu Zhao Dong 《The journal of headache and pain》2022,23(1)
BackgroundThere have been a few studies regarding the pre-attack symptoms (PAS) and pre-episode symptoms (PES) of cluster headache (CH), but none have been conducted in the Chinese population. The purpose of this study was to identify the prevalence and features of PAS and PES in Chinese patients, as well as to investigate their relationships with pertinent factors.MethodsThe study included patients who visited a tertiary headache center and nine other headache clinics between January 2019 and September 2021. A questionnaire was used to collect general data and information about PAS and PES.ResultsAmong the 327 patients who met the CH criteria (International Classification of Headache Disorders, 3rd edition), 269 (82.3%) patients experienced at least one PAS. The most common PAS were head and facial discomfort (74.4%). Multivariable logistic regression analysis depicted that the number of triggers (OR = 1.798, p = 0.001), and smoking history (OR = 2.067, p = 0.026) were correlated with increased odds of PAS. In total, 68 (20.8%) patients had PES. The most common symptoms were head and facial discomfort (23, 33.8%). Multivariable logistic regression analysis showed that the number of triggers were associated with increased odds of PES (OR = 1.372, p = 0.005).ConclusionsPAS are quite common in CH patients, demonstrating that CH attacks are not comprised of a pain phase alone; investigations of PAS and PES could help researchers better understand the pathophysiology of CH. 相似文献
999.
1000.