全文获取类型
收费全文 | 1464853篇 |
免费 | 95179篇 |
国内免费 | 1988篇 |
专业分类
耳鼻咽喉 | 19523篇 |
儿科学 | 49196篇 |
妇产科学 | 41092篇 |
基础医学 | 207144篇 |
口腔科学 | 36980篇 |
临床医学 | 120945篇 |
内科学 | 284970篇 |
皮肤病学 | 27319篇 |
神经病学 | 116353篇 |
特种医学 | 59255篇 |
外国民族医学 | 366篇 |
外科学 | 229859篇 |
综合类 | 29198篇 |
现状与发展 | 1篇 |
一般理论 | 300篇 |
预防医学 | 111231篇 |
眼科学 | 31821篇 |
药学 | 107868篇 |
1篇 | |
中国医学 | 3118篇 |
肿瘤学 | 85480篇 |
出版年
2018年 | 34378篇 |
2017年 | 27001篇 |
2016年 | 31185篇 |
2015年 | 12595篇 |
2014年 | 16799篇 |
2013年 | 25122篇 |
2012年 | 40412篇 |
2011年 | 57306篇 |
2010年 | 40083篇 |
2009年 | 31923篇 |
2008年 | 55869篇 |
2007年 | 62090篇 |
2006年 | 39062篇 |
2005年 | 40510篇 |
2004年 | 40700篇 |
2003年 | 41283篇 |
2002年 | 38553篇 |
2001年 | 58543篇 |
2000年 | 60312篇 |
1999年 | 50977篇 |
1998年 | 14516篇 |
1997年 | 13165篇 |
1996年 | 13224篇 |
1995年 | 12519篇 |
1994年 | 11955篇 |
1993年 | 11022篇 |
1992年 | 41103篇 |
1991年 | 40522篇 |
1990年 | 40080篇 |
1989年 | 38849篇 |
1988年 | 36235篇 |
1987年 | 35479篇 |
1986年 | 33833篇 |
1985年 | 32246篇 |
1984年 | 23998篇 |
1983年 | 20898篇 |
1982年 | 12476篇 |
1981年 | 10948篇 |
1979年 | 22728篇 |
1978年 | 15942篇 |
1977年 | 13752篇 |
1976年 | 13030篇 |
1975年 | 14211篇 |
1974年 | 16723篇 |
1973年 | 16096篇 |
1972年 | 15325篇 |
1971年 | 14232篇 |
1970年 | 13246篇 |
1969年 | 12769篇 |
1968年 | 12007篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
81.
We report a case of intestinal obstruction in a 73-year-old woman caused by ileocolic intussusception. The underlying cause was a giant submucosal ulcerating lipoma (6?×?3.3?×?3.8 cm) extending from the superior mucosal lip of Bauhin’s valve. Abdominal ultrasonography showed a pathognomonic target-like mass appearing as multiple concentric rings. CT scan confirmed the diagnosis. Because of apparent obstruction, a laparotomy with right hemicolectomy and ileocolic anastomosis was performed. Lipomas most frequently occur in the cecum and ascending colon where they represent the most common submucosal mesenchymal tumor. They typically occur in elderly women with an incidence that varies from 0.15 to 0.56 %. Pain, rectal bleeding, and obstruction are typical symptoms. When faced with an intussusception in children, reduction with air per rectum can be performed. In adults, however, malignant cell spreading and seeding is of big concern. Since approximately 20–50 % of all underlying causes are malignant, explorative surgery is favored in adults. 相似文献
82.
Breast Elastography: How to Perform and Integrate Into a “Best-Practice” Patient Treatment Algorithm
Breast elastography has been available for more than 15 years but is not widely incorporated into clinical practice. Many publications report extremely high accuracy for various breast elastographic techniques. However, results in the literature are extremely variable. This variability is most likely due to variations in technique, a relatively steep learning curve, and variability in methods between vendors. This article describes our protocol for performing breast elastography using both strain elastography and shear wave elastography, which produces high sensitivity and specificity. Additionally, we will describe the most commonly known false-positive and false-negative lesions as well as how to detect them. 相似文献
83.
84.
85.
J. Savige L. Amos Frank Ierino H. G. Mack R. C. Andrew Symons P. Hughes 《Ophthalmic genetics》2016,37(4):369-376
Background: Dense deposit disease and atypical hemolytic uremic syndrome are often caused by Complement Factor H (CFH) mutations. This study describes the retinal abnormalities in dense deposit disease and, for the first time, atypical haemolytic uremic syndrome. It also reviews our understanding of drusen pathogenesis and their relevance for glomerular disease. Methods: Six individuals with dense deposit disease and one with atypical haemolytic uremic syndrome were studied from 2 to 40 years after presentation. Five had renal transplants. All four who had genetic testing had CFH mutations. Individuals underwent ophthalmological review and retinal photography, and in some cases, optical coherence tomography, and further tests of retinal function. Results: All subjects with dense deposit disease had impaired night vision and retinal drusen or whitish-yellow deposits. Retinal atrophy, pigmentation, and hemorrhage were common. In late disease, peripheral vision was restricted, central vision was distorted, and there were scotoma from sub-retinal choroidal neovascular membranes and atypical serous retinopathy. Drusen were present but less prominent in the young person with atypical uremic syndrome due to a heterozygous CFH mutation. Conclusions: Drusen are common in forms of C3 glomerulopathy caused by compound heterozygous or heterozygous CFH mutations. They are useful diagnostically but also impair vision. Drusen have an identical composition to glomerular deposits. They are also identical to the drusen of age-related macular degeneration, and may respond to the same treatments. Individuals with a C3 glomerulopathy should be assessed ophthalmologically at diagnosis, and monitored regularly for vision-threatening complications. 相似文献
86.
A novel BRAF mutation in association with primary amelanotic melanoma with oral metastases 下载免费PDF全文
87.
Henry Havel Gregory Finch Pamela Strode Marc Wolfgang Stephen Zale Iulian Bobe Hagop Youssoufian Matthew Peterson Maggie Liu 《The AAPS journal》2016,18(6):1373-1378
Advancing nanomedicines from concept to clinic requires integration of new science with traditional pharmaceutical development. The medical and commercial success of nanomedicines is greatly facilitated when those charged with developing nanomedicines are cognizant of the unique opportunities and technical challenges that these products present. These individuals must also be knowledgeable about the processes of clinical and product development, including regulatory considerations, to maximize the odds for successful product registration. This article outlines these topics with a goal to accelerate the combination of academic innovation with collaborative industrial scientists who understand pharmaceutical development and regulatory approval requirements—only together can they realize the full potential of nanomedicines for patients. 相似文献
88.
89.
90.
M. Alexandra Friedman Charlotte M. Niznik Janelle R. Bolden Lynn M. Yee 《Journal of community health》2016,41(2):354-358
While peer support has been investigated in multiple clinical contexts, its application to the postpartum setting is unknown. The aim was to assess acceptability of a postpartum peer support program for women with diabetes. Observational survey-based needs assessment of forty low-income women with diabetes, receiving care at a major medical institution. Mean age and gravidity were 30.7 years and 3.15 ± 1.67 respectively. 45 % expressed interest in a “buddy.” There was no significant difference between groups desiring and not desiring this program. A majority of respondents desired telephone, text messaging, and in-person contacts (79.2, 72.1, 83.8 %), with 72.5 % of patients desiring diabetes-related activities during clinic waiting time. Many women desire a postpartum diabetes reciprocal peer program for support outside of clinician visits. Patients are receptive to educational services during their wait and outside of clinic time, a potentially valuable opportunity to share important health information. 相似文献