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91.
目的 分析CT扫描剂量、重建算法、层面选择及胸部不同位置对纯磨玻璃肺结节(pGGN)平均CT值测量偏差度的影响,评价影响肺肿瘤性磨玻璃结节(GGN)平均CT值测量的因素.方法 选用CT值为-650 HU的不同直径球形模拟肺pGGN,应用东芝(佳能)64排螺旋CT,设置4种剂量等级自动管电流调制技术扫描,3种三维权重自适应迭代重建剂量降低(AIDR-3D)算法重建,测量1 mm薄层图像肺结节平均CT值,计算偏差度.结果 低剂量模式扫描时,小于10 mm的球形pGGN平均CT值的偏差度较大.3种AIDR算法重建下,相同直径球形pGGN平均CT值偏差度差异较小;pGGN直径越小,球形pGGN平均CT值偏差度越大.在球形pGGN中心层面测量CT值,平均CT值的偏差度最小;偏离中心层面越远,偏差度越大.胸部3个位置的pGGN平均CT值偏差度均不同,肺实质内平均CT值偏差度最小.结论 除重建算法,CT扫描剂量、测量层面选择及结节所在胸部位置对于pGGN平均CT值测量的精准度均可造成影响. 相似文献
92.
Objective:To investigate the action mechanisms of electroacupuncture(EA)on postoperative immunosuppression.Methods:Male C57 BL/6 mice(5–7 weeks old)were randomly divided into:the sham injury group,the surgical trauma stressed group,the EA group[surgery+2/100 Hz EA at Neiguan(PC 6)],and the EA+Nal(surgery+EA+intraperitoneal injection of naloxone).Abdominal surgical trauma stress mice model was established.EA was performed on bilateral PC 6 acupoints by an EA apparatus(2/100 Hz)for 20 min once a day for 3 days.The m RNA expressions of MOR,DOR,and KOR in thymus and L3-5 dorsal root ganglions(DRG)were determined by quantitative real-time polymerase chain reaction(q RT-PCR)and the protein expressions of MOR,DOR,and KOR in thymus were measured by Western blot.Flow cytometry assay was used to detect the levels of T lymphocyte subtypes in the peripheral blood.Results:Surgical trauma induced decreased the m RNA expression level of MOR in both thymus(P<0.01)and L3-L5 DRGs(P<0.05).Moreover,EA treatment not only significantly attenuated the MOR protein and m RNA expression in the thymus(both P<0.05),but also markedly increased expression of DOR and KOR opioid receptor in thymus(P<0.01).However,the m RNA expressions of opioid receptors were not regulated by EA in the DRG(all P>0.05).Furthermore,T lymphocyte population of CD3^+ and CD4^+ was decreased in the peripheral blood after surgical trauma(both P<0.01).EA treatment can significantly elevate the population of CD3^+(P<0.01),CD4^+(P<0.05)and CD8^+T cells(P<0.01).Intraperitoneal injection of the non-selective opioid receptor antagonist naloxone blocked the up-regulation of T lymphocytes by EA.Conclusion:EA may improve postoperative immunosuppression through the peripheral opioid system. 相似文献
93.
冠状动脉粥样硬化性心脏病是全球范围内心血管疾病患者死亡的主要原因,其中以急性ST段抬高型心肌梗死(STEMI)最为凶险。及时经皮冠状动脉介入治疗(PCI)是目前急性STEMI患者最主流的再灌注策略。而部分患者在PCI术后仍不能得到充分的血液灌注,即出现无复流现象(NRP),与随后的不良临床预后密切相关。因此,为了有效恢复再灌注后冠状动脉微循环的血流,防治冠状动脉NRP的发生就显得尤为重要。本文回顾NRP的定义、诊断和临床表现,以病理生理机制为桥梁,提出通过相关预测因子来选择防治策略从而提高PCI疗效。 相似文献
94.
ZHU Yuan Yue ZHENG Rui Zhi WANG Gui Xia CHEN Li SHI Li Xin SU Qing XU Min XU Yu CHEN Yu Hong YU Xue Feng YAN Li WANG Tian Ge ZHAO Zhi Yun QIN Gui Jun WAN Qin CHEN Gang GAO Zheng Nan SHEN Fei Xia LUO Zuo Jie QIN Ying Fen HUO Ya Nan LI Qiang YE Zhen ZHANG Yin Fei LIU Chao WANG You Min WU Sheng Li YANG Tao DENG Hua Cong ZHAO Jia Jun CHEN Lu Lu MU Yi Ming TANG Xu Lei HU Ru Ying WANG Wei Qing NING Guang LI Mian LU Jie Li BI Yu Fang 《Biomedical and environmental sciences : BES》2021,34(1):9-18
Objective The relationship between serum uric acid(SUA)levels and glycemic indices,including plasma glucose(FPG),2-hour postload glucose(2 h-PG),and glycated hemoglobin(HbA1 c),remains inconclusive.We aimed to explore the associations between glycemic indices and SUA levels in the general Chinese population.Methods The current study was a cross-sectional analysis using the first follow-up survey data from The China Cardiometabolic Disease and Cancer Cohort Study.A total of 105,922 community-dwelling adults aged≥40 years underwent the oral glucose tolerance test and uric acid assessment.The nonlinear relationships between glycemic indices and SUA levels were explored using generalized additive models.Results A total of 30,941 men and 62,361 women were eligible for the current analysis.Generalized additive models verified the inverted U-shaped association between glycemic indices and SUA levels,but with different inflection points in men and women.The thresholds for FPG,2 h-PG,and HbA1 c for men and women were 6.5/8.0 mmol/L,11.0/14.0 mmol/L,and 6.1/6.5,respectively(SUA levels increased with increasing glycemic indices before the inflection points and then eventually decreased with further increases in the glycemic indices).Conclusion An inverted U-shaped association was observed between major glycemic indices and uric acid levels in both sexes,while the inflection points were reached earlier in men than in women. 相似文献
95.
目的 了解北极特殊环境对科考队员睡眠质量的影响.方法 应用匹兹堡睡眠质量指数(PSQI)量表对参加我国第9次北极科学考察的科考队员(131人)在出行前、北极考察期间、考察结束后的睡眠情况进行调查,并记录队员的入睡时间点、晨起时间点、入睡时间、睡眠时间.结果 共发放问卷131份,回收有效问卷88份.88名队员中男77名、女11名,年龄为22~50(48.1±17.9)岁,包括船员18人、科考队员70人.考察期间队员的中位晨起时间点比出行前早180 min,入睡时间长于出行前及考察结束3个月后[(45.23±25.84)min vs(18.45±14.34)min、(19.50±12.57)min,P均<0.01],夜晚睡眠时间短于出行前及考察结束3个月后[(6.83±2.24)h vs(8.36±1.45)h、(8.14±1.45)h,P均<0.01].根据PSQI量表评分,考察期间队员的睡眠质量下降、入睡时间延长、睡眠时间缩短、睡眠效率下降、催眠药物使用增加,与出行前相比差异均有统计学意义(P均<0.01).结论 极地极昼及低温环境显著影响北极科学考察时科考队员的睡眠节律,导致入睡时间延长、睡眠时间缩短、助眠药物使用增加,这可能影响到队员的工作状态. 相似文献
96.
YANG Zhen Yu ZHANG Qian ZHAI Yi XU Tao WANG Yu Ying CHEN Bo Wen TANG Xue Jun YUAN Xiao Lin FANG Hong Yun ZHU Yan PANG Xue Hong WANG Shuo XU Juan LI Rui Li SI Xiang ZHAO Wen Hua 《Biomedical and environmental sciences : BES》2021,34(11):891-899
The main purpose of the National Nutrition and Health Systematic Survey for children 0-17 years of age in China (CNHSC) was to collect basic data on the nutrition, development, and health status for children in different regions across China using evidence-based, reliable, and cost-effective approaches. Children and their parents or guardians from seven regions (south, southwest, north, northwest, eastern, central, and northeast China) in China were recruited. A multi-stage stratified randomized sampling method was used. Two provinces were randomly sampled from each of the seven regions, from which one urban district and one rural country were also randomly sampled, resulting in a total of 28 survey counties/districts. Dietary surveys, health examinations, laboratory testing, and questionnaires were used to collect dietary intake, nutritional status, child development, and health status information. Nutrition, health, and lifestyle assessment of children and their parents was determined using the Knowledge Attitude Practice (KAP) survey. Greater than 100,000 children (38,000 children < 6 years of age and 66,000 children 6-17 years of age) completed the survey. The survey provided comprehensive data on child nutrition and health status for future studies and will serve as the basis for an integrated nutrition and health improvement strategies proposal for children in China. 相似文献
97.
TANG Chen FAN Chun GUO Dong Bei MA Xiu Juan CAI Qing Tao CHEN Xiao Xuan ZHANG Min LI Jia Yao AN Qiu Ying ZHAO Ran 《Biomedical and environmental sciences : BES》2021,34(8):656-661,中插17-中插22
Polybrominated diphenyl ethers (PBDEs) are a group of aromatic organic bromine compounds, which have been used in a broad array of polymeric materials (plastics, foams, resins, and adhesives) as brominated flame retardants. They are used in commercial and household products, including textiles, electronic equipment, airplanes, and automobiles, especially in China and the USA, because they are inexpensive with excellent flame-retardant effects[1]. During the past decade, over 14,000 tonnes of PBDEs have entered the market, and have become ubiquitous environmental contaminants[2]. 相似文献
98.
报道松果体区乳头状瘤1例,CT主要表现为稍高密度影,磁共振成像主要表现为短T1信号及囊性变,增强扫描显著强化。 相似文献
99.
目的 通过测定乌司他丁与免疫球蛋白结合蛋白(Bip)在脑缺血再灌注模型大鼠血清、大脑皮层中的浓度,以及两者的体外结合实验、模拟分子对接模型,探讨两者之间的相互作用。方法将36只雄性SD大鼠随机分为两组。正常组(n=18)大鼠经静脉注射乌司他丁20万IU/kg作为对照。实验组(n=18)大鼠在建立大脑中动脉栓塞模型(MCAO)后随即静脉注射乌司他丁20万IU/kg。采用酶标仪法、ELISA法分别测定乌司他丁及Bip在大鼠脑缺血后05、3、24 h中血清、大脑皮层中的浓度。通过乌司他丁与Bip的结合实验计算两者结合率,并利用软件模拟乌司他丁与Bip的分子对接模型。结果在患侧大脑皮层中,实验组乌司他丁浓度在3 h升高,24 h下降,而Bip浓度则在3 h中下降,24 h升高。乌司他丁与Bip的结合率为44%~62%,分子对接结果显示乌司他丁与Bip中的残基可形成范德华力及共轭作用,两者可形成不稳定复合物。结论在缺血大脑皮质中乌司他丁可与Bip形成不稳定复合物,其可能通过影响Bip的表达而在脑缺血再灌注中发挥着一定作用。 相似文献
100.
目的 比较40岁以上高龄女性累积胚胎后移植与非累积胚胎进行移植的妊娠结局。方法选择40岁以上且使用自身卵子进行冻融胚胎移植助孕229例不孕症妇女共338个周期资料,根据患者是否累积胚胎移植分为两组分析妊娠结局。 结果40~49岁女性随着年龄增高,基础卵泡刺激素水平升高(P<0.05),获卵数减少(P<0.05),临床妊娠率和持续妊娠率下降(P<0.05)。在40岁妇女中,累积胚胎移植组的临床妊娠率和持续妊娠率均高于非累积胚胎移植组(42.9% vs. 24.6%,P<0.05),对于41岁、42岁、≥43岁,两组的临床妊娠率、持续妊娠率及早期流产率差异均无统计学意义(P>0.05)。结论对于40岁不孕妇女,多次取卵累积胚胎后移植有助于提高临床妊娠率,对41岁以上女性累积胚胎对于助孕结局的益处有限。 相似文献