全文获取类型
收费全文 | 3036篇 |
免费 | 197篇 |
国内免费 | 118篇 |
专业分类
耳鼻咽喉 | 94篇 |
儿科学 | 175篇 |
妇产科学 | 25篇 |
基础医学 | 319篇 |
口腔科学 | 47篇 |
临床医学 | 306篇 |
内科学 | 778篇 |
皮肤病学 | 58篇 |
神经病学 | 119篇 |
特种医学 | 468篇 |
外国民族医学 | 1篇 |
外科学 | 229篇 |
综合类 | 83篇 |
一般理论 | 1篇 |
预防医学 | 234篇 |
眼科学 | 131篇 |
药学 | 150篇 |
中国医学 | 1篇 |
肿瘤学 | 132篇 |
出版年
2020年 | 20篇 |
2019年 | 34篇 |
2018年 | 40篇 |
2016年 | 45篇 |
2015年 | 40篇 |
2014年 | 45篇 |
2013年 | 77篇 |
2012年 | 92篇 |
2011年 | 90篇 |
2010年 | 82篇 |
2009年 | 85篇 |
2008年 | 91篇 |
2007年 | 134篇 |
2006年 | 103篇 |
2005年 | 107篇 |
2004年 | 65篇 |
2003年 | 65篇 |
2002年 | 70篇 |
2001年 | 73篇 |
2000年 | 71篇 |
1999年 | 74篇 |
1998年 | 112篇 |
1997年 | 117篇 |
1996年 | 125篇 |
1995年 | 80篇 |
1994年 | 74篇 |
1993年 | 69篇 |
1992年 | 48篇 |
1991年 | 78篇 |
1990年 | 58篇 |
1989年 | 81篇 |
1988年 | 83篇 |
1987年 | 84篇 |
1986年 | 61篇 |
1985年 | 91篇 |
1984年 | 60篇 |
1983年 | 45篇 |
1982年 | 45篇 |
1981年 | 36篇 |
1980年 | 50篇 |
1979年 | 39篇 |
1978年 | 27篇 |
1977年 | 34篇 |
1976年 | 42篇 |
1975年 | 27篇 |
1974年 | 23篇 |
1973年 | 21篇 |
1971年 | 24篇 |
1970年 | 21篇 |
1967年 | 17篇 |
排序方式: 共有3351条查询结果,搜索用时 15 毫秒
1.
Patrick Demkowicz BS Renelle Pointdujour-Lim MD Sofia Miguez BA Yesung Lee BS Bailey S. C. L. Jones BS Christopher A. Barker MD Marcus Bosenberg MD PhD David H. Abramson MD Alexander N. Shoushtari MD Harriet Kluger MD Jasmine H. Francis MD Mario Sznol MD Mathieu F. Bakhoum MD PhD 《Cancer》2023,129(20):3275-3286
2.
3.
4.
Chhavi Raj Bhatt Mary Redmayne Michael J. Abramson Malcolm R. Sim Christopher Brzozek Berihun M. Zeleke Geza Benke 《Australasian physical & engineering sciences in medicine / supported by the Australasian College of Physical Scientists in Medicine and the Australasian Association of Physical Sciences in Medicine》2018,41(4):985-991
The aims of this study were to evaluate the weekly and annual cumulative radiofrequency-electromagnetic field (RF-EMF) exposure attributed to mobile phone (MP) use, and assess whether a novel app (Quanta Monitor?) could be employed in a small human sample to characterise the RF-EMF exposures associated with the use of MPs. Ten participants provided their two months’ daily objective data on their MP exposures (i.e. transmitted and received power densities) attributed to different modes of MP usage such as cellular calls, cellular data and Wi-Fi. The results demonstrated that total transmitted power density (cellular phone calls, data and Wi-Fi surfing) could be many orders of magnitude higher than that from the total received power density. Of the total transmitted power density, cellular data use contributed the largest portion. Our study showed that Quanta Monitor? could be employed in prospective assessment of exposures to MPs in epidemiological studies. 相似文献
5.
6.
OBJECTS: This report describes one of the first prospective studies delineating the relationship between infection, host antibody responses and disease exacerbations and remissions in a distinct subset of periodontitis patients infected with A. actinomycetemcomitans. DESIGN: The design of this longitudinal study included visits for each patient approximately every 2 months for up to 3 years. SUBJECTS AND METHODS: Subjects (n = 51) included 16 adult periodontitis (AP) and 11 early-onset periodontitis (EOP) patients with elevated serum IgG antibody to A. actinomycetemcomitans and infection with this microorganism, 12 AP patients with normal levels of anti-Aa antibody, and 12 normal subjects. MEASUREMENT OUTCOMES: Clinical parameters included a gingival index, plaque index, bleeding on probing, pocket depth, and attachment level. Disease activity was defined as loss of attachment during the monitoring intervals. Serum IgG, IgM and IgA antibody to A. actinomycetemcomitans Y4 (serotype b) was quantit-ated using an ELISA. Subgingival plaque samples were examined for A. actinomycetemcomitans using colony immunobiotting. Human serum IgG antibody specificities to outer membrane antigens (OMA) of A. actinomycetemcomitans Y4 were determined using Western immunoblotting. RESULTS: A. actinomycetemcomitans-infected AP patients had a higher frequency of teeth infected when compared to the EOP patients. However, the EOP patients exhibited a trend for higher levels of A. actinomycetemcomitans in those teeth that were infected. Active disease patients demonstrated a significantly greater frequency of infected sites, as well as significant elevations in the proportions of A. octinomycetemcomitans. Both EOP and AP groups showed significantly elevated IgG, IgM and IgA antibody to A. actinomycetemcornitans when compared to a periodontally normal group. The level of IgG antibody was significantly elevated in A. actinomycetemcomitans-positive patients with active disease, while IgA antibody was decreased in a number of the active group patients. Plaque samples derived from active sites showed a clear and significant increase in A. actinomycetemcomitans that occurred from 2–6 months prior to the identification of disease activity. Approximately 70% of the active disease patients showed an increase in IgG antibody level by 2–4 months prior to disease activity. Studies of the antigen reactivity patterns of serum IgG indicated that antibody to antigens of 65, 58, 48, 29 and 24 kDa were more frequent in patients who showed active disease, while those patients with the greatest frequency of active disease appeared to show a general decrease in the recognition of the A. actinomycetemcomitans OMA. CONCLUSIONS: It appears that A. actinomycetemcomitans infection relates to a particular type of disease with accompanying antibody responses that reflect periods of active disease. The dynamics of A. actinomycetemcomitans infection and the level and specificity of systemic antibody responses to this pathogen support an important contribution of the immune response to managing this infection. 相似文献
7.
8.
Ectodermal dysplasias (EDs) are a group of developmental disorders (more than 100) mainly affecting ectodermal tissues and organs. The X-linked hypohidrotic ED (HED) is the most common form of EDs, involving defects in teeth, sweat glands, and hair. In a few reports, HED has been associated with reduced salivary function. In the present case report, a dramatically reduced salivary fluid and acidic proline rich protein production was identified in a 38-year-old man with HED. Computed tomography was performed, revealing that one submandibular gland and both parotid glands were hypoplastic, whereas the right submandibular gland seemed to be absent. These findings are in line with a general developmental disturbance also involving the salivary glands. As salivary tests are inexpensive and easy to perform, it is suggested to routinely evaluate salivary secretion in persons with HED, to prevent a possible negative impact on oral health. 相似文献
9.
10.
A 20-year-old man with chronic granulomatous disease (CGD) and who was receiving granulocyte transfusions for a refractory liver abscess was studied to compare the kinetics of 111In-labeled granulocytes with those of two functional granulocyte assays, nitroblue tetrazolium reduction and chemiluminescence. Transfused granulocytes were eliminated in both rapid and slow phases. Peak recovery was noted in the first sample, which was obtained 10 minutes after transfusion for each assay. The elimination kinetics were similar over 24 hours. These results confirm the value of using 111In-labeled granulocytes as a marker of transfused granulocytes. These data also confirm that the oxidative metabolic function of granulocytes prepared by continuous-flow leukapheresis remains intact while in the recipient's circulation. The response of the patient adds support for the use of granulocyte transfusions in certain patients with CGD. 相似文献