全文获取类型
收费全文 | 72434篇 |
免费 | 6501篇 |
国内免费 | 3494篇 |
专业分类
耳鼻咽喉 | 733篇 |
儿科学 | 1106篇 |
妇产科学 | 567篇 |
基础医学 | 7458篇 |
口腔科学 | 1242篇 |
临床医学 | 8137篇 |
内科学 | 8763篇 |
皮肤病学 | 1279篇 |
神经病学 | 3235篇 |
特种医学 | 3244篇 |
外国民族医学 | 5篇 |
外科学 | 7270篇 |
综合类 | 13504篇 |
现状与发展 | 22篇 |
一般理论 | 9篇 |
预防医学 | 6831篇 |
眼科学 | 1163篇 |
药学 | 8238篇 |
70篇 | |
中国医学 | 4918篇 |
肿瘤学 | 4635篇 |
出版年
2024年 | 250篇 |
2023年 | 955篇 |
2022年 | 2435篇 |
2021年 | 3194篇 |
2020年 | 2386篇 |
2019年 | 1706篇 |
2018年 | 1933篇 |
2017年 | 2005篇 |
2016年 | 1941篇 |
2015年 | 3114篇 |
2014年 | 3869篇 |
2013年 | 4510篇 |
2012年 | 6508篇 |
2011年 | 6857篇 |
2010年 | 5130篇 |
2009年 | 4507篇 |
2008年 | 5240篇 |
2007年 | 5072篇 |
2006年 | 4233篇 |
2005年 | 3577篇 |
2004年 | 2627篇 |
2003年 | 2278篇 |
2002年 | 1842篇 |
2001年 | 1539篇 |
2000年 | 1373篇 |
1999年 | 849篇 |
1998年 | 312篇 |
1997年 | 256篇 |
1996年 | 196篇 |
1995年 | 182篇 |
1994年 | 167篇 |
1993年 | 125篇 |
1992年 | 179篇 |
1991年 | 184篇 |
1990年 | 146篇 |
1989年 | 108篇 |
1988年 | 93篇 |
1987年 | 91篇 |
1986年 | 85篇 |
1985年 | 50篇 |
1984年 | 37篇 |
1983年 | 40篇 |
1982年 | 32篇 |
1981年 | 21篇 |
1980年 | 21篇 |
1979年 | 31篇 |
1978年 | 18篇 |
1977年 | 16篇 |
1976年 | 13篇 |
1974年 | 17篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
Changes of Intestinal Caicitonin Gene-related Peptide in Acute Intestinal Radiation Sickness in Rats
The characteristic distribution of calcitonin gone-related peptide(CGRP)inthe small intestine of rats and its changes in acute intestinal radiation sickness(AIRS)were studied with immunocytochemistry(whole mount stretch preparations of the smallintestine and cryostat sections)and radio-immunoassay.It was found that in all the lay-ers of the intestinal walls,there were large amounts of CGRP immunoreactive(CGRP-I)nerve fibers which existed in especiaUy high density in the myenteric,submucosal andmucosal plexuses.There was also a rather high density of the nerves around the smallvessels of the small intestine and the intestinal crypts.Some CGRP-I neurons were seenin the myenteric and submucosal plexuses.In AIRS,the intestinal CGRP showed a dip-hasic change,in a lower level in the 24th h and a higher level in the 48th and 72nd h af-ter irradiation.The results indicate that CGRP may be related to the regulation of the motility,se-cretion,absorption,sensation,and regional blood flow of the gastrointestinal tract.Pro-bably,CGRP is released under the stress of AIRS and participates in the mechanism ofinjury through many ways especially through the influence on the regional blood flowand the increase of the permeability of blood vessels. 相似文献
62.
64.
Summary;To investigate the distribution of possible novel mutations from parkin gene in variant sub-set of patients with Parkinson’s disease(PD)in China and explore whether parkin gene plays an im-portant role in the pathogenesis of PD,70 patients were divided into early-onset group and late-onsetgroup; 70 healthy subjects were included as controls.Genomic DNA from 70 normal controls andfrom those of PD patients were extracted from peripheral blood leukocytes by using standard proce-dures.Mutations of parkin gene(exon 1—12)in all the subjects were screened by PCR-single strandconformation polymorphism(SSCP),and further sequencing was performed in tue samples with ab-normal SSCP results,in order to confirm the mutation and its location.A new missense mutationGly284Arg in a patient and 3 abnormal bands in SSCP electrophoresis from samples of another 3 pa-tients were found.All the DNA variants were sourced from the samples of the patients with early-on-set PD.It was concluded that Parkin point mutation a 相似文献
65.
66.
对定坤丹(蜜丸)进行了显微鉴定研究,将29种组成药物全部检出,对各组成药物的显微鉴别特征作了简明描述,并附显微特征图。 相似文献
67.
140 patients with brain tumor were treated by CT-guided stereotactic injections of radionuclides, such as Aurum-198 (198 Au), Phosphorus-32 (32 P) and Yttrium-90 (90Y). Of these patients aged from 3 to 67 years (average 37), 64 were male and 76 female. Astrocytoma was found in 75 patients, craniopharyngioma in 46, metastatic carcinoma in 7, meningioma in 5, germinoma in 4 and pituitary adenoma in 3. The tumors were located in the deep part or functionally critical area of the brain. After 267 times of injection of colloidal isotopes, no major adverse effects or complications occurred. Follow-up for 6 to 48 months showed improvement in symptoms in 104 (74.3%) patients and CT scanning showed the diminished tumors.
相似文献
68.
作者对自制新荧光剂EPQS进行了性能测试。结果:量子产率为0.21;最大激发波长和荧光波长分别为375nm和484nm,stokes位移109nm;检测生物化合物常用的缓冲溶液对荧光峰位无影响,对荧光强度影响很小;温度的影响也小(18~43℃,FRI61.5~58.1),PH的影响也不大。说明EPQS不仅荧光参数好,而且稳定性也好。适合在较广泛的环境条件下使用。 相似文献
69.
Dongmin Kang 《Taehan Sohwagi Hakhoe chi》2007,49(5):287-293
Development of in vivo animal imaging instrumentations and methods contributes to the early diagnosis of cancer. Of variable imaging modalities, in vivo optical imaging such as bioluminescence and fluorescence is one of the best methods to measure molecular change of cancer cells. High sensitivity and relatively low cost of optical method gives benefits to apply for translational research in the field of cancer. Nano-probes to label and detect early cancer cells have been developed by nano-chemists and molecular imaging researchers. Quantum dots made from fluorescent semi-conductors show good advantages in term of imaging probes; high quantum yields, large molar extinction coefficients, size-dependent tunable emission and high photostability. To detect a gastrointestinal (GI) cancer, newly developed endoscopes have been used. Among them, near infrared fluorescence endoscope and confocal endomicroscope are good candidates for clinical application. In animal studies, successful results to detect cancer in gastrointestinal tract have been obtained. Prospect of nanoparticles as optical imaging moiety is promising to detect GI cancers if their toxicity is minimized. Future fluorescence confocal endoscope with safe cancer targeting nanoparticles will be useful for the detection and treatment of GI cancers. 相似文献
70.
Suk Hee Heo Yong Yeon Jeong Sang Soo Shin Tae Woong Chung Heoung Keun Kang 《Korean journal of radiology》2007,8(2):180-183
We report an uncommon case of solitary, small hepatic angiosarcoma that was initially considered as a hemangioma. We present the imaging findings, with an emphasis on the initial and follow-up CT and MR findings, as well as report on the more suggestive findings of angiosarcoma than those of a hemangioma. 相似文献