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41.
BACKGROUND AND PURPOSE: The Doppler waveform patterns of loss of diastolic flow, appearance of retrograde diastolic flow, or no detectable flow in the cerebral arteries suggest significantly abnormal cerebral blood flow (CBF). A retrospective study was performed to show that significantly abnormal CBF alone, without clinical criteria, is not necessarily specific to brain death in the young pediatric population. PATIENTS AND METHODS: Forty-seven pediatric patients, from newborn to 4 years of age, were found to have significantly abnormal CBF, including 7 patients with loss of diastolic flow, 28 with retrograde diastolic flow, and 23 with no detectable cerebral flow on serial Doppler sonographic examinations. Their clinical data and sonographic results were collected and analyzed. RESULTS: Forty-two patients died, a few of whom had only transient improvement of cerebral flow. All of the patients with no detectable cerebral flow expired. Five patients survived with or without sequelae. Their underlying conditions that caused increased intracranial pressure were treated by medical and/or surgical intervention, and diastolic reversal of CBF corrected within 1 day in all 5. CONCLUSIONS: Although no detectable flow is a lethal sign, pediatric patients with loss or reversal of diastolic flow may survive with prompt and effective treatment. Using Doppler ultrasound to diagnose cerebral circulatory arrest should be done with caution in pediatric patients. 相似文献
42.
为选择中等场强的MRI听神经瘤成像最佳序列。收集手术和病理证实的听神经瘤135例,分析序列Ⅰ、Ⅱ对内听道中心层面、三叉神经显示率及MR征象的显示情况。结果:序列I择内听道中心层面及三叉神经的显示均优于序列Ⅱ,序列Ⅱ在显示肿瘤内囊变、出血、不肿优于序列I;对肿瘤钙化、肿瘤血管、脑干移位的观察,两者相仿。结果显示:序列I在中等场经下作为听神经瘤成像的首选序列,并中运用到小脑角区MRI成像。 相似文献
43.
T.-N. Wu Chen-Yang Shen Saou-Hsing Liou Guang-Yang Yang K.-N. Ko Show-Lin Chao Chao-Chun Hsu P.-Y. Chang 《International archives of occupational and environmental health》1997,69(6):386-391
To monitor the lead hazards in industries and to investigate the prevalence of elevated blood lead levels (BLLs) in lead-exposed
workers, a lead surveillance system (PRESS-BLLs) has been established and operated in Taiwan, Republic of China, since July
1993. A cohort of lead-exposed workers who received a periodic annual health examination at 55 accredited hospital laboratories
was constructed. A total of 9807 separate BLL measurements were reported to the system in 1994. The mean BLL was 15.8 μg/dl
in male workers and 11.6 μg/dl in female workers. The mean BLL of lead-exposed workers was significantly (P<0.05, z-test) higher than that of the general Taiwanese population (8.6 μg/dl for males and 6.7 μg/dl for females). In addition,
the BLLs of 983 (10.0%) workers exceeded the regulatory action level (40 μg/dl for males; 30 μg/dl for females). The workplaces
and homes of 57% of the workers with elevated BLLs were thoroughly investigated to determine the sources of lead contamination.
These actions identified the causes of elevated BLLs and set up strategies to reduce workers’ lead exposure. The establishment
of this occupational lead surveillance system represents a method for monitoring of lead hazards from occupational and environmental
settings to prevent lead poisoning. The information acquired from the system can help in the setting up of a priority of prevention
and the development of control measures. It is also useful for further monitoring of changes in the BLLs of the lead-exposed-worker
cohort. The Health Department of Taiwan can use this information to evaluate the effectiveness of current industrial hygiene
practice. Subjects with elevated BLLs have been medically treated and placed on long-term follow-up for sequelae.
Received: 2 September 1996/Accepted: 29 November 1996 相似文献
44.
肾细胞癌伴静脉癌栓15例临床分析 总被引:5,自引:1,他引:4
1985~1994年治疗肾细胞癌伴静脉癌栓15例。按癌栓水平分为肾型10例,肝下型4例,肝上型1例。B超和CT检查总确诊率73%。手术14例均完整取出癌栓,术后13例接受5-FU加MMC方案化疗。随访3个月~5年,1例肝下型和2例肾型无瘤存活分别36、43、52个月,余均在术后2年内死亡。认为B超与CT互补应用可基本确诊静脉癌栓,除肝上型和已有血管壁浸润者外大部分癌栓可采用松解游离同时渐渐拉出的方式取出,癌栓水平除肝上型外对预后影响不大。 相似文献
45.
46.
腧穴针感在针刺防治疾病过程中发挥着重要作用。本文从针刺作用的感受器,腧穴针感的外周传入神经,以及针感与中枢神经的关系,诸方面,列举大量实验结果和理论,阐明针感形成的物质基础是神经系统。 相似文献
47.
(沈张悦)(邵静芳)(王晓林)(朱慧芬)ExperimentalStudyonAnti-tumorEffectofSplenocytesInducedbyAnti-CD3McAb,PHAandIL-2¥SHENGuan-xin,WANGXiao-li... 相似文献
48.
49.
Li Ming Yang Jing Shen Guan-xin Zhang Qian Liu Shen-pei Liu Zhong-bei Ye Wei-xin 《华中科技大学学报(医学英德文版)》1994,14(4):209-212
Summary T cell activation and proliferation via CD3-TCR complex were investigated by lymphocyte DNA synthesis in vitro. Several interfering factors were also discussed. The
result indicated that lymphocyte activation and proliferation are calciumdependent. A rise of cytoplasmic free Ca2+ quickly following activation with CD3 McAb is mainly due to intracellular mobilization of Ca2+, while lymphocyte proliferation needs both intracellular mobilization of Ca2+ as well as influx of extracellular Ca2+. It was confirmed that CTX sensitive G protein plays a role in regulating T cell proliferation by pretreatment with CTX suppressing
lymphocyte3H-TdR incorporation obviously. PLC and PKC inhibitor neomycin and P. S. S could also decrease T cell proliferation. 相似文献
50.
目的:探讨膀胱癌中凝集素受体分布与其分化程度和浸润深度的关系。方法:应用生物素标记的花生凝集素(PNA)、麦胚凝集素(WGA)及刀豆凝集素(ConA)等3种凝集素对52例人体膀胱癌、10例正常人体膀胱粘膜,进行亲合组织化学法研究。结果:发现正常膀胱粘膜PNA、WGA受体阴性,PNA受体阳性率随膀胱癌病理分级的上升而递增,差异具有显著性意义(P<0.05)。PNA、WGA受体阳性率在浸润性肿瘤中明显高于浅表性肿瘤(P<0.05)。结论:提示PNA、WGA受体阳性率与膀胱癌分化程度和浸润深度有关。 相似文献