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181.
An automatic system for marine meiobenthos separation was developed by using laser-induced fluorescence technology. Rose Bengal was used as organism dye and the spectrums of Rose Bengal were measured. Laser-induced fluoresce ncesystem was established to detect marine meiobenthos in sediments. Data obtained from experiments were analyzed by using a mathematical model. The results showed that laser-induced fluorescence technology worked well in the system. The system could select the meiobenthos efficiently and precisely. 相似文献
182.
Character of HBV (hepatitis B virus) polymerase gene rtM204V/I and rtL180M mutation in patients with lamivudine resistance 总被引:2,自引:0,他引:2
Objectives: To investigate the relationship between HBV (hepatitis B virus) polymerase gene 180 and 204 sites mutation and lamivudine resistance. Methods: One hundred forty-one patients with lamivudine resistance after lamivudine treatment and 60 chronic hepatitis B patients without lamivudine treatment were enrolled in this study. The serum HBV DNA mutation was analyzed by sequence detection via polymerase chain reaction (PCR). The sequences of the same patient were analyzed before and after lamivudine treatment. Results: One hundred and nine lamivudine resistance patients had HBV YMDD (tyrosine-methionine-aspartate-aspartate) mutation. Among them, 45 patients had rtL180M/M204V mutation (41.28%), 28 patients had rtL 180M/M204I mutation (25.70%) and 36 patients had rtM204I mutation (33.02%). There were 6 patients with rtL180M mutation in 32 lamivudine resistance patients. Sixty chronic hepatitis patients without lamivudine treatment had no mutations. Conclusions: HBV mutations, which play an important role in lamivudine resistance usually locate at polymerase gene 204 site; 180 site mutation was also observed in these patients. Evaluation of the anti-virus therapy by surveillance of the two sites mutations is of importance. 相似文献
183.
Chinese local undergraduate universities are in a process of transition into universities of applied sciences. Important aspects of this include strengthening cooperation between universities and industry, cultivating applied talent needed in industry, improving students’ employment rates, and promoting economic development. Internships are an important way to help students gain practical experience and deepen university-industry cooperation. The purpose of this paper is to analyze the challenges of the existing internship process in an undergraduate university in China and give suggestions to improve internship quality. Qualitative data from 35 students and 12 administrators/faculty were collected at a local undergraduate university, H University (HU), in central China, which is currently undergoing the process of becoming a university of applied sciences. The findings of the study show issues with the university’s model, including communication between industry and university, internship evaluation, student guidance, and internship quality. Recommendations based on the literature are provided. 相似文献
184.
GAO Li SHI Xue-yun 《美中教育评论》2007,4(1):14-19,24
In the base of utility and marginal utility, the article put forward the concept of utility and marginal utility of educational outlay and the theory of them, and analyzed the actuality of educational resource deployment in our country, gave some advice about how to improve our educational resource deployment of compulsory education. 相似文献
185.
A first order system model of fracture healing 总被引:1,自引:0,他引:1
INTRODUCTION Fracture healing is an important research subject in biomechanics. During the last years, many theories and simulation models have been proposed for de- veloping a comprehensive view of the mechanisms controlling bone morphogenesis. Pauwels (1960) was one of the first authors to propose a theory of tissue differentiation in response to local mechanical stress and strain. He assumed that deviatoric stresses com- prise the specific stimulus for the formation of fibrous connecti… 相似文献
186.
RSS made easy: a basic guide for librarians 总被引:1,自引:0,他引:1
Really Simple Syndication (RSS) uses extensive markup language (XML) to constantly scan the content of Web sites for updates, which will then be delivered to subscribers' desktops or mobile devices through an RSS feed. RSS helps professionals stay current while reducing workloads. Librarians need to get familiar with RSS to educate their users, to stay current in information technology, and to generate and disseminate selected information to target user groups. doi:10.1300/J115v26n01_04. 相似文献
187.
Preimplantation genetic diagnosis (PGD) refers to a procedure for genetically analyzing embryos prior to implantation, improving
the chance of conception for patients at high risk of transmitting specific inherited disorders. This method has been widely
used for a large number of genetic disorders since the first successful application in the early 1990s. Polymerase chain reaction
(PCR) and fluorescent in situ hybridization (FISH) are the two main methods in PGD, but there are some inevitable shortcomings
limiting the scope of genetic diagnosis. Fortunately, different whole genome amplification (WGA) techniques have been developed
to overcome these problems. Sufficient DNA can be amplified and multiple tasks which need abundant DNA can be performed. Moreover,
WGA products can be analyzed as a template for multi-loci and multi-gene during the subsequent DNA analysis. In this review,
we will focus on the currently available WGA techniques and their applications, as well as the new technical trends from WGA
products. 相似文献
188.
The new prevalence data regarding the estimated global number of human immunodeficiency virus positive (HIV+) cases, i.e., including people who are either aware or unaware of their HIV infection in 2010, lead many to wonder why the
increase in incidence has reached today’s unprecedented level and escalated within such a short time. This, in spite of prevention
campaigns in countries affected by HIV/acquired immune deficiency syndrome (AIDS) with their urgent messages aimed at preventing
HIV transmission by promoting changes in individual’s behavior. This article analyzes the background of the prevention strategies,
in particular their political, social and legal concepts in terms of human rights, and reveals traits of human behavior not
considered thus far. A radical reappraisal is necessary, at social and legislative levels, as well as options additional to
current concepts. When ethical issues come up, they become blamed for outmoded moralistic positions. However, ignoring the
reality has led to dire consequences from prioritizing individual human rights over society’s collective need to prevent the
spread of HIV. 相似文献
189.
Winegrape is an important perennial crop in California, USA. Each year California winegrape farming consumes about 20 million
kilograms of pesticides that have been a pollutant source to the fresh water systems of the state. The variation of pesticide
use among winegrape growers has been significant. It has been observed that some growers have developed effective ways to
reduce pesticide use, yet control pests efficiently to ensure harvest. Identification of the growers with low and high pesticide
use is very helpful to extension programs that aim on reducing pesticide environmental risk. In this study, an index approach
is proposed to quantitatively measure pesticide use intensity at grower level. An integrated pesticide use index is developed
by taking pesticide quantity and toxicity into account. An additive formula and a multiplying formula were used to calculate
the pesticide use index, i.e., PUI and PUIM. It was found that both PUI and PUIM were capable of identifying the low and high
pesticide users while PUI was slightly more conservative than PUIM. All pesticides used in California winegrape farming were
taken into account for calculating the indices. Madera County, one of the largest winegrape producers in California, was taken
as an example to test the proposed approach. In year 2000, among the total 208 winegrape growers, 28 with PUI≤10 and 34 with
10<PUI≤20 were identified as low pesticide users who were characterized with both low quantity and low toxicity of pesticide
use. Most of the growers had small-sized vineyards, i.e., one field and small planted areas. Furthermore, they had very low
pesticide use intensity, used only 1–2 types of pesticides (mainly fungicides), applied few pesticides (1–3 only), and emphasized
the use of low toxicity compounds. Meanwhile, 19 growers with PUI>60, identified as high pesticide users, had large-sized
vineyards, i.e., more fields and large planted areas. They used all types of pesticides and many compounds, which indicated
that their pest controls heavily depended on pesticides rather than on-farm management. Through the case study, the proposed
approach proved to be useful for analyzing the growers’ pesticide use intensities and interpreting their pesticide use behaviors,
which led to a new start point for further investigation of searching ways to reduce pesticide environmental risk. 相似文献
190.
In this paper, we report the clinical and molecular features of the distinct TGFBI (human transforming growth factor β-induced, OMIM No. 601692) gene-linked corneal dystrophy. Altogether, five pedigrees and
ten unrelated individuals diagnosed as corneal dystrophy were recruited. Peripheral venous DNA was extracted, and then amplified
by polymerase chain reaction (PCR) and scanned for mutation by single-stranded conformation polymorphism (SSCP). Direct DNA
sequencing was used to analyze the mutations of the TGFBI gene. In our study, thirty patients from five pedigrees and ten sporadic patients were diagnosed as four TGFBI gene-linked corneal dystrophies of granular corneal dystrophy type I (GGCD I), Avellino corneal dystrophy (ACD), lattice
corneal dystrophy type I (LCD I), and lattice corneal dystrophy type IIIA (LCD IIIA), and in total, seven disease-causing
mutations, namely R555W, A546D, A546T, and T538P mutations in exon 12, R124H and R124C mutations in exon 4, and P501T mutation
in exon 11, were identified, while four polymorphisms of V327V, L472L, F540F, and 1665-1666insC were screened in exons 8,11,
and 12. The study ascertained the tight genotype-phenotype relationship and confirmed the clinical and genetic features of
four TGFBI gene-linked corneal dystrophies. 相似文献