全文获取类型
收费全文 | 18650篇 |
免费 | 1167篇 |
国内免费 | 435篇 |
专业分类
耳鼻咽喉 | 118篇 |
儿科学 | 469篇 |
妇产科学 | 246篇 |
基础医学 | 1014篇 |
口腔科学 | 210篇 |
临床医学 | 3169篇 |
内科学 | 4055篇 |
皮肤病学 | 139篇 |
神经病学 | 1379篇 |
特种医学 | 1067篇 |
外国民族医学 | 1篇 |
外科学 | 2457篇 |
综合类 | 2317篇 |
现状与发展 | 2篇 |
预防医学 | 749篇 |
眼科学 | 129篇 |
药学 | 1501篇 |
16篇 | |
中国医学 | 583篇 |
肿瘤学 | 631篇 |
出版年
2023年 | 316篇 |
2022年 | 550篇 |
2021年 | 734篇 |
2020年 | 726篇 |
2019年 | 761篇 |
2018年 | 776篇 |
2017年 | 700篇 |
2016年 | 600篇 |
2015年 | 634篇 |
2014年 | 1214篇 |
2013年 | 1321篇 |
2012年 | 1011篇 |
2011年 | 1131篇 |
2010年 | 904篇 |
2009年 | 862篇 |
2008年 | 813篇 |
2007年 | 807篇 |
2006年 | 724篇 |
2005年 | 653篇 |
2004年 | 515篇 |
2003年 | 508篇 |
2002年 | 396篇 |
2001年 | 333篇 |
2000年 | 284篇 |
1999年 | 228篇 |
1998年 | 231篇 |
1997年 | 240篇 |
1996年 | 174篇 |
1995年 | 182篇 |
1994年 | 165篇 |
1993年 | 149篇 |
1992年 | 116篇 |
1991年 | 101篇 |
1990年 | 107篇 |
1989年 | 99篇 |
1988年 | 78篇 |
1987年 | 43篇 |
1986年 | 60篇 |
1985年 | 123篇 |
1984年 | 136篇 |
1983年 | 84篇 |
1982年 | 114篇 |
1981年 | 79篇 |
1980年 | 64篇 |
1979年 | 68篇 |
1978年 | 55篇 |
1976年 | 44篇 |
1975年 | 62篇 |
1974年 | 48篇 |
1973年 | 45篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
51.
同型半胱氨酸及抗磷脂抗体与深静脉血栓形成和复发关系的研究 总被引:2,自引:0,他引:2
目的通过检测深静脉血栓形成(DVT)患者血浆中的同型半胱氨酸(Hey)和抗磷脂抗体(APLA)水平,探讨DVT形成和复发的因素,并寻找DVT复发的预报因子。方法选取2001年1月至2003年4月期间哈尔滨医科大学附属第二医院血管外科收治的60例DVT患者,其中初发组和复发组各30例,另随机选取门诊就诊经证实无DVT的下肢静脉曲张或深静脉功能不全的30例患者作为对照组,同时选取复发DVT的一级亲属组30例。用荧光偏振免疫法测定Hey,用酶联免疫吸附试验(ELISA)检测APLA中的抗心磷脂抗体(AcLA)水平(IgG、IgM型)并测定狼疮抗体(LA)阳性率。结果初发与复发DVT组患者血浆中的Hey和ACLA-IgG及ACLA-IgM水平均高于对照组和复发DVT一级亲属组,差异有统计学意义(P〈0.01)。复发DVT的一级亲属组的血浆中的Hey水平高于对照组(P〈0.05)。各组的LA阳性率差异无统计学意义(P〉0.05)。结论DVT患者血浆中Hey和APLA均升高,Hey和APLA与深静脉血栓形成有密切关系。Hey升高与DVT复发有关,可能是DVT复发的预报因子。 相似文献
52.
动脉自旋标记法磁共振成像在颈动脉狭窄性脑缺血疾病中的初步应用 总被引:2,自引:0,他引:2
目的:对比研究颈动脉严重狭窄患者动脉自旋标记法(ASL)和动态磁化率效应对比剂增强(DSC)磁共振脑灌注成像表现,探讨ASL的临床运用价值。材料和方法:健康自愿者12例,行DSC和ASL,计算左侧大脑中动脉供血区与右侧相应区域相对脑血流量(rCBF)比值并进行比较。病例组为单侧颈内动脉狭窄程度≥70%患者32例,计算DSC和ASL所得的患侧与健侧大脑中动脉供血区rCBF比值并进行比较。结果:12例健康自愿者所测的DSC和ASL的rCBF比值分别为1.0012±0.1030和1.0015±0.1611,无统计学差异。32例患者中,15例患者灌注异常,DSC与ASL的rCBF比值相比无显著性差异(P=0.072)。结论:ASL序列能快速无创的提供脑灌注情况,可作为初步了解颈动脉狭窄性脑缺血疾病脑灌注情况的常规检查方法。 相似文献
53.
Ø. Lidegaard 《Acta neurologica Scandinavica》1987,75(6):427-433
The mortality of cerebrovascular diseases in Denmark was analysed for men and women 15-44 years of age, in a 14-year period before and after the appearance of oral contraceptives (OC) in 1966. 1,670 deaths were registered over 28 years, during which the female incidence of cerebrovascular deaths increased by 19% (P less than 0.025), while the male mortality was unchanged. Women showed a percentage increase in deaths from cerebral thromboembolic attacks (CTA) of 33%, men a fall of 14%. The increase of female CTA deaths was most pronounced in the young fertile group, the age group with a high OC use. A relative risk of CTA of 3.3-4.5 for OC users compared with non-users could explain the CTA trend difference between women and men. No other single risk factor responsible for the observed trends could be identified. Both women and men had a significant increase in the mortality of subarachnoidal hemorrhages, and a significant fall in the mortality of intracerebral hemorrhages. 相似文献
54.
55.
A double or bilobar gallbladder as a cause of severe complications after (laparoscopic) cholecystectomy 总被引:1,自引:1,他引:0
A double or bilobar gallbladder is a rare congenital anomaly. If not recognized during preoperative evaluation or operation, it can cause severe complications. We describe two cases in which a second operation had to be performed because of the presence of a second or bilobar gallbladder that was not recognized in the preoperative evaluation and during (laparoscopic) cholecystectomy. The types of anomalies, the concomitant pathology, and treatment are discussed. 相似文献
56.
Percutaneous transluminal coronary angioplasty in a patient with paroxysmal nocturnal hemoglobinuria
Ping-Ching Fong Yau-Ting Tai Chu-Pak Lau John Li Florence Hiu-Yee Yap Raymond Liang Albert Kwok-Wai Lie 《Catheterization and cardiovascular interventions》1992,25(2):144-147
Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired chronic hemolytic anemia associated with an unusual susceptibility to hemolytic crisis, infection, and venous thrombosis which would be aggravated by a number of factors including surgery. We report a case of PNH undergoing percutaneous transluminal coronary angioplasty and discuss the corresponding perioperative management. 相似文献
57.
Mercury ingested from dietary sources has potent neurotoxic and teratogenic effects. Initial studies have shown that mercury may also affect fetal lung development. Since these pulmonary effects may play a role in subsequent neonatal morbidity and mortality due to compromising of the development of the lung, mercury effects in fetal and neonatal lung were investigated. Methylmercuric chloride (MMC), 1,000 ppm (15 mg/kg of body weight), was administered via an intragastric tube to timed-pregnant Swiss/Webster mice on day 9 of gestation. Lungs from fetuses on gestational day 18 and from neonates on days 1, 5, or 10 after birth were studied. Significant changes in MMC-exposed lungs compared to controls occurred at postnatal day 1. At this time, lung weight per gram body weight increased, phospholipid content per gram of lung or per microgram of DNA decreased, while DNA per gram of lung increased. Methylmercury appears to have delayed lung maturation. Cuboidal epithelial cells in alveolar tubules contained conspicuous glycogen deposits, and differentiation of alveolar type II cells was adversely affected. These results suggest that prenatal exposure to methylmercury may be detrimental to lung development, specifically to the initiation of surfactant synthesis, by delaying the normal pattern of maturation of the alveolar type II cells within the lungs. Pediatr Pulmonol. 1994; 17:11–21 . © 1994 Wiley-Liss. Inc. 相似文献
58.
采自贵州省猪尾鼠的吸虱具有特殊的形态。李氏欣奇虱独自成为一科。双叶盲鼠虱隶拟血虱科。拟血虱科中的拟血虱属和钩板虱属均寄生于鼹科,裂虱属和盲鼠虱属则寄生于睡鼠科和刺山鼠科。后者曾被置于睡鼠科。研究食虫目动物的吸虱将可能对吸虱与其宿主动物的偕同进化提供更多的证据。 相似文献
59.
60.
刘毅 《山东中医药大学学报》1992,(6)
治疗脑出血,急症抢救期先以安宫牛黄丸之类芳香开窍醒脑,并予以止血,待神志清醒,血压稳定后,再施以补气活血、化瘀通络、平肝潜阳之法,脑血栓亦先开窍醒脑,后用自拟安脑化瘀汤以安脑通络、活血化瘀治之;老年性痴呆则以滋补肝肾、填精健脑为主,佐平肝活血、醒脑开窍为辅,药用自拟醒脑复聪汤;蛛网膜下腔出血以清脑醒神、镇痉熄风为治,药用自拟清脑熄风汤。 相似文献