全文获取类型
收费全文 | 58025篇 |
免费 | 3057篇 |
国内免费 | 304篇 |
专业分类
耳鼻咽喉 | 664篇 |
儿科学 | 1711篇 |
妇产科学 | 1991篇 |
基础医学 | 8428篇 |
口腔科学 | 960篇 |
临床医学 | 4891篇 |
内科学 | 12888篇 |
皮肤病学 | 1625篇 |
神经病学 | 5134篇 |
特种医学 | 1564篇 |
外国民族医学 | 31篇 |
外科学 | 8244篇 |
综合类 | 229篇 |
一般理论 | 14篇 |
预防医学 | 4265篇 |
眼科学 | 977篇 |
药学 | 3839篇 |
中国医学 | 172篇 |
肿瘤学 | 3759篇 |
出版年
2023年 | 283篇 |
2022年 | 292篇 |
2021年 | 844篇 |
2020年 | 538篇 |
2019年 | 893篇 |
2018年 | 1475篇 |
2017年 | 1126篇 |
2016年 | 1120篇 |
2015年 | 1378篇 |
2014年 | 1465篇 |
2013年 | 2270篇 |
2012年 | 3518篇 |
2011年 | 3521篇 |
2010年 | 1871篇 |
2009年 | 1521篇 |
2008年 | 3144篇 |
2007年 | 3195篇 |
2006年 | 3082篇 |
2005年 | 3267篇 |
2004年 | 3192篇 |
2003年 | 2865篇 |
2002年 | 2756篇 |
2001年 | 1581篇 |
2000年 | 1565篇 |
1999年 | 1310篇 |
1998年 | 412篇 |
1997年 | 351篇 |
1996年 | 326篇 |
1995年 | 352篇 |
1994年 | 301篇 |
1993年 | 272篇 |
1992年 | 785篇 |
1991年 | 714篇 |
1990年 | 694篇 |
1989年 | 706篇 |
1988年 | 624篇 |
1987年 | 639篇 |
1986年 | 533篇 |
1985年 | 554篇 |
1984年 | 397篇 |
1983年 | 350篇 |
1982年 | 300篇 |
1981年 | 240篇 |
1979年 | 317篇 |
1978年 | 244篇 |
1977年 | 236篇 |
1975年 | 235篇 |
1974年 | 253篇 |
1973年 | 236篇 |
1968年 | 251篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
Rosangela Saga Kamikawa Marlene Fenyo Pereira Angela Fernandes Maria Inês Meurer 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2006,101(3):374-378
OBJECTIVE: To determine the location in soft tissues of the calcifications, similar to calcified carotid atheromas, that can be observed radiographically in the cervical region in panoramic radiographs. STUDY DESIGN: In each anatomic cadaver specimen preserved in formol, consisting of the head and neck, radiopaque spheres (made from gutta-percha) were positioned in anatomic structures of the cervical region that can be sites of calcification. For each anatomic structure marked in this way, panoramic radiography was performed, consisting of 17 radiographs. The images obtained were analyzed by 24 examiners who indicated which radiographs, in their opinion, presented the radiopaque reference projected in the region of bifurcation of the carotid artery. Analysis of 2 proportions from agreement and disagreement was used to determine radiopacities that could be confused in panoramic radiographs with calcified atheromas in the carotid artery. RESULTS: The results showed that 75% (18) of the examiners correctly indicated the reference in the bifurcation of the carotid artery and 79.2% (19) indicated a triticeous cartilage as calcified atheroma of the carotid artery. CONCLUSIONS: Calcified atheromas of the carotid artery are not the only features that can produce radiopaque images lateral to the panoramic radiograph; the presence of calcification in the triticeous cartilage also can induce an erroneous diagnosis of calcified carotid atheroma. 相似文献
73.
Rakel Kling Marc Corbière Rebecca Milord Janet G Morrison Kevin Craib Annalee Yassi Claire Sidebottom Catherine Kidd Victoria Long Sharon Saunders 《AAOHN journal》2006,54(11):481-487
This study examined the use and effectiveness of the Alert assessment form. The form is part of the Alert system, used by one large acute care hospital to identify patients with a propensity for violence. All reported incidents of patient violence from August 1, 2003, through December 31, 2004, were included in patient charts. One hundred seventeen violent patient charts were reviewed and compared with 161 non-violent patient charts, randomly chosen from the same time period. Overall use of the Alert assessment form for violent and non-violent patients was 75.7% and 35.4%, respectively. The assessment form was found to have moderate sensitivity (71%) and high specificity (94%). It is reasonably effective in identifying potentially violent or aggressive patients when it is used according to protocol. Efforts to improve the tool are warranted, as is evaluation of its benefit in settings with low prevalence of violence. Also, greater effort must be taken to prevent violence once an aggressive patient has been identified. 相似文献
74.
75.
Ch. Deliveliotis F. Sofras D. Picramenos Ch. Bellos N. J. Stavropoulos Th. Becopoulos 《International urology and nephrology》1995,27(4):365-367
We present a very rare case of gigantic hydrocalycosis which was caused by an obstructed stone. It was so large that it displaced
the rest kidney into the contralateral lumbar fossa giving the appearance of a crossed ectopic kidney. 相似文献
76.
Dalton Pompêo de Pina M.D. 《Aesthetic plastic surgery》1990,14(1):27-33
Recently many mammaplasty techniques have been presented with special attention paid to the resulting scar's size and its position. The surgeon should try to hid the scar, and if the inverted T incision is used, its horizontal branch should be as short as possible and kept in the breast area. Neverthelss, excessive concern about the final scar size should not interfere with the final results of the mammaplasty as far as shape, volume and lasting results are concerned. The author presents his experience in mammaplasty with respect to the volume, the shape, and the scar size interrelationships. 相似文献
77.
78.
Catherine Loudes Geneviève Rougon Claude Kordon Annie Faivre-Bauman 《The European journal of neuroscience》1997,9(11):2323-2333
We have previously shown that the morphological and biochemical maturation of developing rat hypothalamic dopaminergic neurons is accelerated when they are cocultivated with pituitary intermediate lobe cells, one of their targets. Only two subsets of hypothalamic dopaminergic neurons (arcuate, A12, and periventricular, A14, nuclei) may project to the pars intermedia. In order to determine whether the two populations are equally responsive to coculture conditions, we microdissected the hypothalamus of 17-day-old rat fetuses in two fragments containing cell bodies from the A12 and from the A14 regions, prepared neuronal cultures from both portions and incubated them separately with intermediate lobe cells. The presence of intermediate lobe cells increased tyrosine hydroxylase levels in both dopaminergic neuron subsets, but morphological differentiation was accelerated in dopaminergic neurons originating in the arcuate nucleus only. We then investigated whether physical contact between developing arcuate neurons and their target cells was a prerequisite of the morphological effect by interposing a semipermeable membrane between cultivated neurons and intermediate lobe cells in transwell culture dishes. The morphological effect was no longer observed under transwell coculture conditions, pointing to the involvement of membrane-bound molecules. Accordingly, the stimulating effect of coculture on arcuate dopaminergic neurons was completely abolished by the removal of polysialic acid on neural cell adhesion molecules by endoneuraminidase N treatment. Thus, maturation of A12 and A14 dopaminergic neurons exhibits differential susceptibility to intermediate lobe target cells, and polysialylated-NCAM is required for the contact-dependent effect. 相似文献
79.
Physician based surveillance system for occupational respiratory diseases: the experience of PROPULSE, Québec, Canada. 总被引:1,自引:0,他引:1
下载免费PDF全文
![点击此处可从《Occupational and environmental medicine》网站下载免费的PDF全文](/ch/ext_images/free.gif)
OBJECTIVE: To evaluate the feasibility of implementing a physician based surveillance system of occupational respiratory diseases (PROPULSE) in Québec with regard to physician participation rate, characteristics of reported cases, and comparison with official statistics from the Workers' Compensation Board (WCB). METHODS: All chest physicians and allergists in Québec were asked to report suspected new cases of occupational respiratory diseases, on a monthly basis, between October 1992 and September 1993. For each case, personal information was collected and the physician's opinion on whether the condition was related to work was categorised as highly likely, likely, and unlikely. RESULTS: Of the 161 physicians initially approached, 68% participated. Physicians rated 48% of suspected cases as highly likely, 29% as likely, and 20% as unlikely. The most often reported diagnosis was asthma (63%), followed by diseases related to asbestos (16%). Silicosis was less frequent (5%) but it was reported for six workers under 40 of whom five were involved in sandblasting activities. The high proportion of cases of asthma probably reflects the increasing importance of this disease but may also reflect the different patterns of reporting among physicians with different expertise. The distribution of cases by diagnostic category is quite different between the PROPULSE system and that of the WCB (annual mean number of compensated cases during a four year period). Asthma and allergic alveolitis are more frequent in PROPULSE, reactive airways dysfunction syndrome are about the same in both systems, and other diseases are more frequent among compensated cases. The most frequent sensitising agents reported for asthma were the same in both systems (isocyanates, flour, and wood dust). 15% of the PROPULSE cases were not covered by the WCB, and therefore would not be found in the board's official statistics. CONCLUSIONS: A physician based reporting procedure can be implemented as part of a surveillance system to supplement data from other sources and thus provide a better understanding of the occurrence of occupational respiratory diseases. 相似文献
80.