全文获取类型
收费全文 | 436705篇 |
免费 | 43139篇 |
国内免费 | 26359篇 |
专业分类
耳鼻咽喉 | 4413篇 |
儿科学 | 7124篇 |
妇产科学 | 2755篇 |
基础医学 | 25016篇 |
口腔科学 | 8304篇 |
临床医学 | 51943篇 |
内科学 | 35209篇 |
皮肤病学 | 4576篇 |
神经病学 | 9833篇 |
特种医学 | 17642篇 |
外科学 | 38364篇 |
综合类 | 123368篇 |
现状与发展 | 105篇 |
预防医学 | 51656篇 |
眼科学 | 5106篇 |
药学 | 53206篇 |
734篇 | |
中国医学 | 47320篇 |
肿瘤学 | 19529篇 |
出版年
2024年 | 2343篇 |
2023年 | 5601篇 |
2022年 | 14341篇 |
2021年 | 17734篇 |
2020年 | 15362篇 |
2019年 | 8158篇 |
2018年 | 8920篇 |
2017年 | 12287篇 |
2016年 | 9139篇 |
2015年 | 17150篇 |
2014年 | 21805篇 |
2013年 | 27941篇 |
2012年 | 40787篇 |
2011年 | 42838篇 |
2010年 | 38805篇 |
2009年 | 34576篇 |
2008年 | 35664篇 |
2007年 | 34801篇 |
2006年 | 30297篇 |
2005年 | 23677篇 |
2004年 | 16571篇 |
2003年 | 13702篇 |
2002年 | 10595篇 |
2001年 | 9572篇 |
2000年 | 7164篇 |
1999年 | 2460篇 |
1998年 | 566篇 |
1997年 | 488篇 |
1996年 | 487篇 |
1995年 | 364篇 |
1994年 | 381篇 |
1993年 | 230篇 |
1992年 | 168篇 |
1991年 | 150篇 |
1990年 | 115篇 |
1989年 | 77篇 |
1988年 | 64篇 |
1987年 | 89篇 |
1986年 | 99篇 |
1985年 | 62篇 |
1984年 | 37篇 |
1983年 | 55篇 |
1982年 | 36篇 |
1965年 | 38篇 |
1964年 | 37篇 |
1963年 | 38篇 |
1959年 | 62篇 |
1958年 | 49篇 |
1957年 | 38篇 |
1956年 | 32篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
高分辨CT在蝶骨骨折诊断中的应用价值 总被引:1,自引:0,他引:1
目的:探讨高分辨CT在蝶骨骨折诊断中的应用价值。方法:回顾性分析我院头面部外伤高分辨CT检查346例,详细观察蝶骨受损情况。结果:蝶骨骨折86例,发生率为24.9%,明显高于颞骨骨折,其中蝶骨大翼骨折81例(占94%),蝶骨体部骨折66例(占76.7%),蝶骨小翼骨折49例(占56.9%),蝶骨翼突骨折19例(占22.1%),2个以上部位的多处骨折81例,占94.1%;合并头面部其它部位骨折79例,占91.1%。结论:水平位和冠状位结合高分辨CT可准确及时发现蝶骨骨折及其部位,蝶骨骨折多为多部位骨折,头面部外伤合并蝶骨骨折提示病情复杂。 相似文献
992.
993.
994.
Abstract: The influence of endoscopic examination on the occurrence of arrhythmia was investigated electrocardiographically in 30 patients with cardiovascular disease who underwent transesophageal echocardiography (TEE) (group A) and 38 patients with digestive tract disease who underwent upper gastrointestinal endoscopy (UGIE) (group B). The mode and frequency of arrhythmia during the examination were compared between the two groups. (1) Arrhythmia was more frequently observed in group A (22 of 30, 73.3%) than in group B (9 of 38, 23.7%) patients (p<0.001). The common arrhythmias in both groups were supraventricular premature beat and ventricular premature beat. Serious arrhythmias, such as 2nd degree atrioventricular block and ventricular fibrillation were detected only in group A patients. (2) The region of the esophagus where the tip of the probe or scope was located was classified into three segments: upper (0–15 cm), middle (15–35 cm) and lower (35 cm<). Arrhythmias tended to be frequent when the tip of the probe or scope was located in the middle segment of the esophagus. These data indicate that arrhythmias observed during TEE or UGIE are related to the underlying heart disease. Furthermore, the middle segment of the esophagus appears to be particularly susceptible to the provocation of arrhythmia. 相似文献
995.
视盘血管炎——关于混合型的研讨 总被引:2,自引:0,他引:2
对60例(63眼)视盘血管炎的临床分型进行了探讨,结果表明,除分为Ⅰ、Ⅱ两型外,尚存在混合型,当视盘睫状血管炎性病变波及中央静脉,或两个血管系统同时受炎症侵犯时,即可再现混合型的临床表现,视盘明显水肿,视网膜静脉迂张,散在渗出,出血,动脉狭细。眼底荧光血管造影可见视盘荧光早期充盈明显迟缓,后期渗漏面积〉2.0PD,视网膜循环时间延长,混合型兼有Ⅰ,Ⅱ两型的临床特征,应作为一个独立类型存在,同时观察 相似文献
996.
997.
Background Prosia gland in D2 (PGD2) is a very important mast cell product during the early-phase nasal allergic reaction. However, the quantification of PGD2 in nasal secretions has not yet been well established. Objective Quantitative determination of PGD2 in nasal secretions of atopic patients (n=17) after nasal allergen challenge (NAC) and in non-allergic healthy volunteers (n=10). Methods The nasal microsuction sampling technique was used to obtain the nasal secretions with an exactly known and minimally diluted volume. A sensitive and specific enzyme immunoassay was chosen to measure the more stable 11-methoxime derivative of PGD2. which was obtained after extraction in acelone/ethanol and conversion using methoxamine-HCl. The concentrations of PGD2 in nasal secretions obtained from 10 non-allergic healthy volunteers were used as reference values. Results There was no significant difference in the concentrations of PGD2 between men (median: 569pg/mL) and women (median: 407pg/mL), nor between the baseline concentrations from atopic patients (median: 410pg/mL) and non-allergic controls (median: 477 pg/mL). In the atopic patient group, PGD2 did not significantly increase during the entire sampling period after NAC. The absence of PGD2 response contrasted with the nasal symptoms manifested by sneezing, increased nasal airway resistance, and the significant increases of the concentrations of histamine, tryptase, and leukotriene C4 (LTC4) 5min after NAC. Conclusion This observation suggests that the measurement of PGD2 alone in the nasal secretions does not give reliable information on mast cell activation during a nasal allergic reaction. 相似文献
998.
999.
卡马西平多晶型的研究 总被引:4,自引:0,他引:4
红外吸收图谱与中国药典图谱不符合的卡马西平(A晶),可通过用较高浓度乙醇使其转为B晶而符合规定,经 ̄(13)CNMR、MS、X线衍射分拆,证实该两种晶体为同质异晶。 相似文献
1000.
乙型肝炎患者可溶性白细胞介素2受体水平变化 总被引:5,自引:0,他引:5
本研究应用酶联免疫吸附试验(ELISA)检测了103例乙型肝炎各型患者及26倒乙肝病毒(HBV)携带者血清中可溶性白细胞介素2受体(sIL-2R)水平,并结合临床资料进行分析。结果发现:各型患者及HBV 携带者sIL-2R 水平均明显高于正常对照(P<0.01~0.001),其升高程度与病情轻重呈正比,在去除危重患者酶—胆分离时谷丙转氨酶(ALT)过低的影响后,sIL-2R 水平与ALT 有良好的正相关关系(r=0.38.p<0.05);作者认为sIL-2R 能够较好地反映疾病的活动状况,动态观察血清sIL-2R 水平的变化,对判断和评价HBV 感染后的病情演变及免疫失衡状态具有重要意义。 相似文献