全文获取类型
收费全文 | 133334篇 |
免费 | 9569篇 |
国内免费 | 5524篇 |
专业分类
耳鼻咽喉 | 972篇 |
儿科学 | 1745篇 |
妇产科学 | 2713篇 |
基础医学 | 10392篇 |
口腔科学 | 2713篇 |
临床医学 | 15729篇 |
内科学 | 8954篇 |
皮肤病学 | 434篇 |
神经病学 | 10365篇 |
特种医学 | 7779篇 |
外国民族医学 | 26篇 |
外科学 | 33087篇 |
综合类 | 24318篇 |
现状与发展 | 12篇 |
一般理论 | 1篇 |
预防医学 | 6572篇 |
眼科学 | 2045篇 |
药学 | 10112篇 |
98篇 | |
中国医学 | 5505篇 |
肿瘤学 | 4855篇 |
出版年
2024年 | 449篇 |
2023年 | 2135篇 |
2022年 | 4071篇 |
2021年 | 5552篇 |
2020年 | 5046篇 |
2019年 | 4231篇 |
2018年 | 4108篇 |
2017年 | 4756篇 |
2016年 | 5223篇 |
2015年 | 4968篇 |
2014年 | 9392篇 |
2013年 | 9770篇 |
2012年 | 8744篇 |
2011年 | 9557篇 |
2010年 | 7900篇 |
2009年 | 7484篇 |
2008年 | 7148篇 |
2007年 | 7079篇 |
2006年 | 6420篇 |
2005年 | 5507篇 |
2004年 | 4481篇 |
2003年 | 3855篇 |
2002年 | 3045篇 |
2001年 | 2710篇 |
2000年 | 2156篇 |
1999年 | 1777篇 |
1998年 | 1463篇 |
1997年 | 1337篇 |
1996年 | 1123篇 |
1995年 | 947篇 |
1994年 | 770篇 |
1993年 | 581篇 |
1992年 | 542篇 |
1991年 | 402篇 |
1990年 | 373篇 |
1989年 | 338篇 |
1988年 | 323篇 |
1987年 | 252篇 |
1986年 | 250篇 |
1985年 | 358篇 |
1984年 | 306篇 |
1983年 | 232篇 |
1982年 | 250篇 |
1981年 | 210篇 |
1980年 | 184篇 |
1979年 | 134篇 |
1978年 | 125篇 |
1977年 | 98篇 |
1976年 | 87篇 |
1975年 | 59篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Beatrix Tirkanits M.D. F.R.C.S.C. Rollin K. Daniel M.D. F.A.C.S. 《Aesthetic plastic surgery》1990,14(1):111-117
A new technique of forehead rhytidectomy is presented that combines the best features of the coronal incision with those of the anterior hairline incision. The plane of dissection is formed by an anterior subcutaneous plane dissecting a lateral subgaleal plane. This approach is particularly valuable in patients with high foreheads, severe static wrinkling, and asymmetrical eyebrows.Presented in part at the Annual Meeting of the American Society of Aesthetic Plastic Surgeons, Boston, MA, 1984 相似文献
22.
A retrospective review was done of 69 children and adolescents (7-17 years old) who underwent 75 arthroscopies of the knee during a 5-year period. Girls were overrepresented (71%). Thirty-eight were children under the age of 16. Of 46 injuries, 34 (74%) happened during sports. Children and adolescents were divided into two age groups based on their presumed state of skeletal maturity (boys 9–15 and girls 7–14 in group I and boys 16–17 and girls 15–17 in group II); meniscal lesions were equally common in the two groups, whereas anterior cruciate ligament tears were more common in older children (NS). Eleven of 17 (65%) anterior cruciate ligament lesions were combined with other intra-articular pathology, most often meniscal tears (9/11). As in other studies, half of the prearthroscopic diagnoses were incorrect. A high frequency of incorrect prearthroscopic diagnoses and of combined lesions justifies arthroscopy as an important diagnostic tool in children and adolescents with a history of twisting knee injury or chronic nonspecific knee problems. Girls practising ball games seem to be especially prone to knee injuries leading to arthroscopy. 相似文献
23.
24.
The in vitro capacity of sympathetic superior cervical ganglia (SCG) to take up [3H]choline from the extracellular medium, to synthesize acetylcholine from [3H]choline, and to release [3H]acetylcholine in response to a high K+ concentration, were examined in rats throughout a 24-h cycle. Both the release of [3H]acetylcholine and the synthesis of [3H]acetylcholine from [3H]choline exhibited significant diurnal variations, showing maxima during the first half of the night. After these maxima, nocturnal acetylcholine release and synthesis decayed to daytime levels and remained low until the end of the night. [3H]Choline uptake by rat SCG did not vary significantly throughout a 24-h period. A 1.5-h exposure of rats to darkness at the 5th hour of light phase of the daily photoperiod did not change significantly any parameter studied. A 20-min, 5-Hz, electrical stimulation of the preganglionic trunk of SCG excised from rats at noon increased significantly subsequent K+-induced [3H]acetylcholine release but did not change [3H]acetylcholine synthesis. In decentralized SCG of rats subjected to a unilateral SCG decentralization and a contralateral sham-operation 7 days earlier, [3H]acetylcholine release and synthesis were highly reduced or abolished at the decentralized side, while [3H]choline uptake remained unaltered. The present results suggest that an activation of preganglionic rat SCG neurons takes place during the first half of the scotophase. 相似文献
25.
26.
①目的 了解猪同种原位心脏移植术后早期一氧化氮 (NO)、一氧化氮合酶 (NOS)含量的变化 ,及其与早期缺血再灌注损伤的关系。②方法 建立猪同种原位心脏移植模型。供心在移植前低温保存 (Thomas液 ,4℃ ) 4h ,移植成功心脏复搏后 2h取材。应用组织化学方法测定心肌组织中NO、NOS的含量 ,应用核酸原位末端标记法 (TUNEL)测定心肌细胞凋亡指数 ,作为评价心肌缺血再灌注损伤的指标。以正常心肌及单纯缺血心肌组织作为对照。③结果 移植后心肌组织NO、NOS的含量较缺血组与正常组低 ,差异有显著意义 (F =2 7.2 2 9、16 .2 0 3,q =5 .716~ 6 .4 12 ,P <0 .0 1)。移植组心肌细胞凋亡指数与正常组及缺血组比较明显升高 ,差异有显著性(F =16 3.884 ,q =7.4 82、6 .975 ,P <0 .0 1)。心肌组织NO、NOS含量与心肌细胞凋亡指数呈负相关关系 (r =- 0 .886、- 0 .795 ,P <0 .0 1)。④结论 猪心脏移植后早期心肌缺血再灌注损伤所致的细胞死亡主要表现为心肌细胞凋亡 ;再灌注期间内源性NO、NOS的减少参与了心脏移植后早期缺血再灌注损伤的发生 相似文献
27.
目的 观察后路钛网椎板成形侧块内固定加植骨术治疗脊髓型颈椎病的临床效果。方法 自1999年至今,共有16例脊髓型颈椎病患者经后路钛网椎板成形侧块内固定加植骨术治疗,对治疗结果进行临床及X线评定。结果 通过平均2年5个月的随访,所有病例都得到了改善,其中优6例、良8例、可2例,优良率为93.8%;术后椎管矢状径平均增加4.2mm,钛网无位置变化,并已被再生骨固定。结论 在进行后路减压的同时,钛网椎板成形及侧块内固定,尤其适用于有节段性不稳的脊髓型颈椎病并椎管狭窄、后纵韧带骨化症的治疗。 相似文献
28.
Albert B. Zajko M.D. Klaus M. Bron William L. Campbell 《Cardiovascular and interventional radiology》1987,10(1):28-31
Biliary obstruction and multiple hepatic abscesses occurred in a patient after ligation of a segmental branch of the right
hepatic duct. The patient was successfully managed by transhepatic biliary drainage and balloon dilatation of an internal
fistula that developed between the ligated duct and a Roux limb of jejunum. Internal biliary fistulas may be dilated using
interventioanl radiologic techniques to permit nonobstructed bile flow. Implications for the nonsurgical treatment' of biliary
strictures are discussed. 相似文献
29.
跳水运动员颈椎损伤的生物力学研究 总被引:1,自引:1,他引:0
作者通过在新鲜成人颈椎标本上做了椎体静力性负荷和动力性负荷实验,表明颈椎在后伸位应力为前屈位的50%,最大应力位于颈椎4-6,是跳水运动员头颈部入水时引起颈椎致伤的生物力学因素。 相似文献
30.
Summary A patient with severe, recurrent posterior epistaxis was shown at angiography to have an aneurysm of the petrous portion of the internal carotid artery (ICA). Since childhood, she had had pain related to eustachian tube blockage by the aneurysm. An endovascular balloon embolization of the aneurysm was successful with preservation of the parent artery. The treatment resulted in resolution of the symtpoms. The report confirms the usefulness of an angiographic protocol in evaluating vascular problems. 相似文献