全文获取类型
收费全文 | 13004篇 |
免费 | 21篇 |
国内免费 | 2篇 |
专业分类
教育 | 10010篇 |
科学研究 | 1299篇 |
各国文化 | 12篇 |
体育 | 528篇 |
文化理论 | 403篇 |
信息传播 | 775篇 |
出版年
2024年 | 2篇 |
2023年 | 17篇 |
2022年 | 33篇 |
2021年 | 32篇 |
2020年 | 62篇 |
2019年 | 105篇 |
2018年 | 2288篇 |
2017年 | 2172篇 |
2016年 | 1660篇 |
2015年 | 190篇 |
2014年 | 183篇 |
2013年 | 448篇 |
2012年 | 280篇 |
2011年 | 729篇 |
2010年 | 860篇 |
2009年 | 459篇 |
2008年 | 662篇 |
2007年 | 1165篇 |
2006年 | 86篇 |
2005年 | 411篇 |
2004年 | 465篇 |
2003年 | 379篇 |
2002年 | 136篇 |
2001年 | 19篇 |
2000年 | 29篇 |
1999年 | 5篇 |
1998年 | 5篇 |
1997年 | 21篇 |
1996年 | 13篇 |
1995年 | 14篇 |
1994年 | 14篇 |
1993年 | 4篇 |
1992年 | 6篇 |
1991年 | 7篇 |
1990年 | 8篇 |
1989年 | 7篇 |
1987年 | 3篇 |
1986年 | 3篇 |
1985年 | 4篇 |
1981年 | 4篇 |
1978年 | 3篇 |
1977年 | 5篇 |
1976年 | 6篇 |
1974年 | 2篇 |
1970年 | 2篇 |
1959年 | 1篇 |
1957年 | 1篇 |
1956年 | 1篇 |
1948年 | 1篇 |
1872年 | 2篇 |
排序方式: 共有10000条查询结果,搜索用时 109 毫秒
911.
Franky D. Shah Rasheedunnisa Begum Bhairavi N. Vajaria Kinjal R. Patel Jayendra B. Patel Shilin N. Shukla Prabhudas S. Patel 《Indian journal of clinical biochemistry : IJCB》2011,26(4):326-334
Oral cancer has emerged as an alarming public health problem with increasing incidence and mortality rates all over the world.
Therefore, the implementation of newer screening and early detection approaches are of utmost importance which could reduce
the morbidity and mortality associated with this disease. Sensitive and specific biomarkers for oral cancer are likely to
be most effective for screening, diagnosis, staging and follow-up for this dreaded malignancy. Unlike other deep cancers,
oral cancer is located in oral cavity. Hence, the direct contact between saliva and oral cancer lesion makes the measurement
of tumor markers in saliva an attractive alternative to serum and tissue testing. The DNA, RNA and protein molecules derived
from the living cancer cells can be conveniently obtained from saliva. Thus, salivary biomarkers, a non-invasive alternative
to serum and tissue-based biomarkers may be an effective modality for early diagnosis, prognostication and monitoring post
therapy status. In the current post-genomic era, various technologies provide opportunities for high-throughput approaches
to genomics and proteomics; which have been used to evaluate altered expressions of gene and protein targets in saliva of
oral cancer patients. The emerging field of salivary biomarkers has great potentials to prove its clinical significance to
combat oral cancer. Hence, we have reviewed importance of several salivary genomics and proteomics biomarkers for oral cancer. 相似文献
912.
Gupta S Verma M Gupta AK Kaur A Kaur V Singh K 《Indian journal of clinical biochemistry : IJCB》2011,26(2):178-181
Thyroid function tests are very important for the diagnosis and monitoring of patients with thyroid dysfunction. The guidelines
recommend serum thyroid stimulating hormone (TSH) as the single most reliable test to diagnose all common forms of hypothyroidism
and hyperthyroidism. The aim of this study was to analyze the ordering pattern for thyroid function tests by physicians and
the analysis of results based on the clinical history. The mean age of the patients was 32.5 ± 6.5 years. Majority of samples
(87.7% of total) were received from the departments of Medicine and Gynae. Thyroid profiles (47.5%) were ordered more frequently
as compared to TSH only (46%). There was no significant difference in the percentage of normal reports for both types of tests.
77.8% of TFT and 76.6% of TSH samples had results within the reference range. The percentage of abnormal results was 13.7%
in the patients who were screened for thyroid disorders. There is a need to redefine the case definition for thyroid dysfunction
and order the appropriate test in a rational and cost effective manner. 相似文献
913.
Singh B Goswami B Gupta VK Chawla R Mallika V 《Indian journal of clinical biochemistry : IJCB》2011,26(2):131-135
Ensuring quality of laboratory services is the need of the hour in the field of health care. Keeping in mind the revolution
ushered by six sigma concept in corporate world, health care sector may reap the benefits of the same. Six sigma provides
a general methodology to describe performance on sigma scale. We aimed to gauge our laboratory performance by sigma metrics.
Internal quality control (QC) data was analyzed retrospectively over a period of 6 months from July 2009 to December 2009.
Laboratory mean, standard deviation and coefficient of variation were calculated for all the parameters. Sigma was calculated
for both the levels of internal QC. Satisfactory sigma values (>6) were elicited for creatinine, triglycerides, SGOT, CPK-Total
and Amylase. Blood urea performed poorly on the sigma scale with sigma <3. The findings of our exercise emphasize the need
for detailed evaluation and adoption of ameliorative measures in order to effectuate six sigma standards for all the analytical
processes. 相似文献
914.
Thomas Gould 《Publishing Research Quarterly》2011,27(1):36-53
Perhaps nothing strikes more fear into the hearts of all tenure-track professors than the process itself. Are four papers in this journal good enough? Are eight papers in another okay? What if someone doesn’t like me or my area of research? These issues have plagued academia since the first essay was penned by the first researcher hundreds of years ago. While personal bias and journal preference continue to infect honest tenure reviews, solutions exist. This does not mean we have a magic bullet to solve issues of bullying or elitism. However, if we are honest in our desire to improve the Academy, we should avail ourselves of every possible tool for improvement. This essay is based on a survey sent to 2,500 mass communication educators. Of the almost 500 respondents, roughly 10% took the time to express emotions that ranged from fear and confusion to outright rage and anger, all because what ought to be clear is not. The author offers 10 ideas of how academia can improve its evaluation of new faculty, as well as a few suggestions regarding the unnecessary inclusion of personal issues in a process that ought to be about creating better researchers and teachers. 相似文献
915.
916.
Stuart Glover 《Publishing Research Quarterly》2011,27(1):54-61
The article documents the editorial relationship between Peter Carey and his New York based editor for Knopf, Gary Fisketjon,
who worked with Carey on his True History of the Kelly Gang. This account provides the basis for a discussion of how globalised publishing, while promising unity—a single text across
all territories—has instead introduced a tension into the previously cohesive triad of author, editor, and the single authorized
text. As Fisketjon’s experience lays bare, major contemporary texts that are published in multiple editions in different global
centers may well proceed through competing or at least parallel editing processes with different presses, different editors,
and in different publishing territories. The authorized single edition, even of major literary texts, has been replaced by
competing editions. The single edit and editor have been replaced by competing “servant[s] of the writer” (to use Fisketjon’s
phrase). Cohesion, while not quite giving way to disunity, gives way to multiplicity and plurality. The experience of the
Kelly Gang book is cast against a longer narrative of Carey’s interactions with editors including the University of Queensland Press
(UQP) from the 1970s and Faber from the 1980s. 相似文献
917.
Mitchell Weisberg 《Publishing Research Quarterly》2011,27(2):188-196
The purpose of this article is to add to the collective body of knowledge on student behavior and attitudes relative to the
adoption of digital textbooks. The article summarizes an ongoing research project that examines past, current and evolving
behavior in the classroom related to digital textbooks and school. It includes students, faculty and administrative attitudes
behaviors and perceptions. This research was undertaken at the Sawyer Business School of Suffolk University in Boston, Massachusetts.
Student attitudes and behavior toward their use of digital textbooks (eTextbooks) in higher education was examined in an ongoing
longitudinal study over two years at Sawyer Business School, Suffolk University. Students in the class were divided into six
teams. Five of the teams were assigned an eTextbook device and the sixth team was given a paper textbook for use through the
semester. The digital technologies examined were: Amazon Kindle, Sony eReader Touch, Apple iPad, enTourage eDGe, and CourseSmart.
Student attitudes and behaviors were examined pre and post class by survey each semester, and during the semesters through
quizzes, journals and classroom discussion. Differential learning was measured between the six teams. Student attitudes and
behaviors are becoming more receptive to and accepting of using digital textbooks each year. There was no significant difference
in learning between the eTextbook devices teams or between them and the paper textbook team. 相似文献
918.
Joseph J. Esposito 《Publishing Research Quarterly》2011,27(1):13-18
The migration from print books to ebooks is more than a change of format; it is also the first step in an ongoing process,
whose final outcome is hard to predict. Ebooks are likely to lead to a restructuring of the industry by enabling cross-border
commerce. This in turn is likely to lead to difficult disputes over territorial rights. It appears probable that these disputes
will be resolved by an assertion of the dominance of the American market and the publishers that already serve it well, as
authors are likely to place their rights with practitioners in the largest markets. This in turn will lead to the acquisition
of many smaller “national” publishers, which cannot compete on a world stage with truly global publishers. But rather than
simply becoming sources of editorial product for American-based global marketing machines, smaller publishers operating in
different regions will respond through innovation, both in product design (attempting to do electronically what cannot be
done in print) and in developing new marketing plans that the giant publishers would be indisposed to pursue. 相似文献
919.
James Lichtenberg 《Publishing Research Quarterly》2011,27(2):101-112
The forces for change in the 600 hundred-year history of book publishing have never been more powerful and fundamental than
in 2011. Barely 12 months ago, what publishers viewed as “innovation” was the creation of digitized versions of physical books
to be ‘consumed’ on e-reading devices. As 2011 begins, that change is largely regarded as accepted business practice, and
the edge of “innovation” is moving in more complex directions. Publishing finds itself in the midst of a ‘phase shift’ from
the scarcity model of print to a complex, new world of digital abundance. The dimensions of change, moreover, its speed, and
its extent are still unknown. While book publishing begins with the creative work of authors, digital technologies are turning
the business models inside out. Among the forces for change acting on book publishing, this article examines several phenomena
that are working their way in from the edge to the center of the industry, including complex interwoven considerations around
container, context, and customer. 相似文献
920.
Dustin Hillard Eren Manavoglu Hema Raghavan Chris Leggetter Erick Cantú-Paz Rukmini Iyer 《Information Retrieval》2011,14(3):315-336
The critical task of predicting clicks on search advertisements is typically addressed by learning from historical click data.
When enough history is observed for a given query-ad pair, future clicks can be accurately modeled. However, based on the
empirical distribution of queries, sufficient historical information is unavailable for many query-ad pairs. The sparsity
of data for new and rare queries makes it difficult to accurately estimate clicks for a significant portion of typical search
engine traffic. In this paper we provide analysis to motivate modeling approaches that can reduce the sparsity of the large
space of user search queries. We then propose methods to improve click and relevance models for sponsored search by mining
click behavior for partial user queries. We aggregate click history for individual query words, as well as for phrases extracted
with a CRF model. The new models show significant improvement in clicks and revenue compared to state-of-the-art baselines
trained on several months of query logs. Results are reported on live traffic of a commercial search engine, in addition to
results from offline evaluation. 相似文献