全文获取类型
收费全文 | 13594篇 |
免费 | 124篇 |
国内免费 | 122篇 |
专业分类
教育 | 8973篇 |
科学研究 | 1675篇 |
各国文化 | 89篇 |
体育 | 1717篇 |
综合类 | 19篇 |
文化理论 | 170篇 |
信息传播 | 1197篇 |
出版年
2021年 | 79篇 |
2020年 | 155篇 |
2019年 | 205篇 |
2018年 | 949篇 |
2017年 | 944篇 |
2016年 | 720篇 |
2015年 | 232篇 |
2014年 | 246篇 |
2013年 | 1570篇 |
2012年 | 281篇 |
2011年 | 517篇 |
2010年 | 468篇 |
2009年 | 358篇 |
2008年 | 387篇 |
2007年 | 487篇 |
2006年 | 200篇 |
2005年 | 251篇 |
2004年 | 513篇 |
2003年 | 434篇 |
2002年 | 361篇 |
2001年 | 402篇 |
2000年 | 256篇 |
1999年 | 162篇 |
1998年 | 106篇 |
1997年 | 106篇 |
1996年 | 96篇 |
1995年 | 107篇 |
1994年 | 101篇 |
1993年 | 77篇 |
1992年 | 152篇 |
1991年 | 119篇 |
1990年 | 135篇 |
1989年 | 149篇 |
1988年 | 110篇 |
1987年 | 129篇 |
1986年 | 120篇 |
1985年 | 135篇 |
1984年 | 120篇 |
1983年 | 123篇 |
1982年 | 96篇 |
1981年 | 81篇 |
1980年 | 91篇 |
1979年 | 135篇 |
1978年 | 87篇 |
1977年 | 72篇 |
1976年 | 91篇 |
1975年 | 65篇 |
1974年 | 72篇 |
1973年 | 68篇 |
1971年 | 66篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
981.
J. J. Vasileva 《Scientific and Technical Information Processing》2011,38(4):243-250
The problem of the necessity of creating an effective means of access to information resources and their management in the
innovative sphere under conditions of the formation of a common information space is described. The model of an information
and analytical system at the regional level is suggested as a solution and the methodological approaches and requirements
for setting up such a system are defined. The architecture and logic of functioning of the regional information and analytical
system of innovative sphere is reviewed. 相似文献
982.
M. N. Kotov 《Scientific and Technical Information Processing》2011,38(2):78-82
This work considers the topic of international conflict (IC) analysis and examines a number of present approaches to their
analysis. The developed IC phase-factor model and a general scheme for predicting IC development directions are described. 相似文献
983.
Innovation informatization for state financial control bodies 总被引:1,自引:0,他引:1
A. Ya. Bystryakov V. V. Mizintseva 《Scientific and Technical Information Processing》2011,38(2):69-77
The lack of a unified system of innovative information support of the activity of state bodies and at the same time the need
for quick, qualified, and motivated decisions determine the role of informatization for bodies of state financial control
(SFC). The article considers the basic features of information supply to SFC bodies and the requirements imposed on information
in the financial sphere; the basic objectives and problems of information supply; risks and problems in the process of informatization
in the SFC system; and the ways to deal with the existing problems within the Unified Information Space to be formed in accordance
with the Electronic State and the Efficiency of State Governance program (by 2015). 相似文献
984.
This paper examines a controversial research programme aimed at the production of transgenic cows in New Zealand. It emphasizes the contested representation of the research, in its promotion, in its governance, and in the opposition sparked amongst environmentallanti-genetic modification groups and within the Māori community. The paper contends that the case of New Zealand's genetically modified cows certainly reveals some unique features of the prevailing economic, geographical and cultural context, but nonetheless has salience for the broader understanding of the promotion, public reception and governance of genetic modification. 相似文献
985.
Farrokhi E Shayesteh F Asadi Mobarakeh S Roghani Dehkordi F Ghatreh Samani K Hashemzadeh Chaleshtori M 《Indian journal of clinical biochemistry : IJCB》2011,26(3):244-248
Familial hypercholesterolemia (FH) is an autosomal dominant disorder of lipoprotein metabolism caused mainly by mutations
in the low-density lipoprotein receptor (LDLR) and apolipoprotein B 100 (APOB) genes. Until now, the molecular basis of FH
has been demonstrated in detail in many populations, but there is still very limited Molecular data concerning FH in Iran.
The aim of this study was to characterize the LDLR and APOB gene mutations in an Iranian population. A total of 30 non-related
Iranian possible FH subjects were studied. Diagnosis of FH was based on the Dutch Lipid Clinic Network diagnostic criteria.
All samples were initially tested for three common APOB gene mutations including R3500Q, R3500 W and R3531C using PCR-RFLP
assay. Subsequently, promoter and coding region of the LDLR gene was screened by PCR-SSCP analysis and positive results were
confirmed by DNA sequencing. Four previously reported polymorphisms 1413G > A, 1725C > T, 1773T > C and 2140 + 5G > A were
found in ~17% (5/30) of population studied. Moreover, no variation was found in APOB gene. Our data indicated that LDLR and
APOB gene mutations have not contribution to possible FH in Iranian population studied here. However, we examined three common
APOB mutations and LDLR in only 30 patients, and to determine the role of these genes in developing FH in Iran, more FH samples
and populations needed to be investigated for the mutations of the related genes. 相似文献
986.
Venkateshwari A Sri Manjari K Krishnaveni D Nallari P Vidyasagar A Jyothy A 《Indian journal of clinical biochemistry : IJCB》2011,26(2):136-139
Pancreatic fibrosis is a key pathological feature in the etiology of chronic pancreatitis that leads to obliteration of exocrine
and endocrine pancreatic tissues and its replacement by fibrous tissue resulting in clinical manifestations. Matrix metalloproteinase
9 is a member of the MMP family that is also known as gelatinase B, degrades type IV collagen of extracellular matrix and
basal membrane. The present study is aimed at evaluating the clinical significance of plasma concentration of MMP-9 in chronic
pancreatitis. The samples were obtained from 112 chronic pancreatitis patients and an equal number of age and sex matched
healthy controls. MMP-9 levels were quantitatively measured by ELISA assay. Statistical analysis was applied to test the significance
of results. The present study revealed a significant increase of plasma MMP 9 levels in chronic pancreatitis patients compared
to control subjects. Elevated levels were also observed in all the patient groups compared to control subjects with regard
to sex, age, addictions etc. MMP-9 degrades the type IV collagens in normal basement membrane, which in turn activates the
pancreatic stellate cells which promote the development of pancreatitic fibrosis. Thus, elevated plasma levels of MMP-9 may
act as a susceptibility factor for the development of chronic pancreatitis. 相似文献
987.
Kannan Vaidyanathan M. P. Narayanan D. M. Vasudevan 《Indian journal of clinical biochemistry : IJCB》2011,26(4):319-325
Organic acidurias are an important class of inherited metabolic disorders arising due to defect in intermediary metabolic
pathways of carbohydrate, amino acids and fatty acid oxidation. This review summarizes the current knowledge about the important
organic acidurias in the Indian population. Specifically, diagnosis and principles of treatment of organic acidurias are covered.
The salient features of common organic acidurias as well as their prevalence in various parts of the world are reviewed in
some detail. 相似文献
988.
989.
Khan S Bhargava A Pathak N Maudar KK Varshney S Mishra PK 《Indian journal of clinical biochemistry : IJCB》2011,26(2):161-168
The present study evaluated the plausible role of circulating biomarkers in immune pathogenesis of chronic hepatitis considered
a priority in clinical hepatology. Total viral load of chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) patients
was quantified and correlation studies were performed with circulating levels of Th1/Th2 cytokines; C reactive protein and
circulating nucleosomes; glutathione reductase (GR) and superoxide dismutase. To our knowledge, the study is first among its
kind that validates strong positive correlation of viral load with IL-4, IL-6, GR in HBV and IL-6, IL-10, GR in HCV infections.
Although, multi-centric studies including large cohorts are required for translating our findings to clinical practice, however,
role of these biomarkers with potential diagnostic or prognostic significance might be helpful in clinical assessment of high-risk
individuals, thereby, designing interventional strategies, towards development of personalized medicare. The results of our
study also offer valuable insights of immune signaling mediators engaged in development of hepatocellular carcinoma. 相似文献
990.
Biswas D Vettriselvi V Choudhury J Jothimalar R 《Indian journal of clinical biochemistry : IJCB》2011,26(2):172-177
Mutations in different regions of adiponectin gene have been reported to be associated with obesity, atherosclerosis and type
2 diabetes mellitus. The present study was aimed to investigate the association among SNP 45 T > G of adiponectin gene and
type 2 diabetes in South Indian population. 75 clinically diagnosed case of type 2 diabetes were studied and compared with
75 apparently healthy controls. The genotype frequency of SNP45 T > G in exon 2 of adiponectin gene was determined by PCR
based restriction enzyme analysis using the restriction enzyme SmaI. (recognition site: CCC↓GGG). Three kind of genotypes: wild type TT (470 bp), heterozygous type TG (470 bp, 336 bp, 134 bp)
and homozygote mutant type GG (336 bp, 134 bp) were studied. A positive association has been found between SNP45 T > G and
type 2 diabetes in the study population (P = 0.010, OR = 3.797, 95% CI = 1.312–10.983). Therefore, SNP45T > G in adiponectin gene may be one of the risk factors for
type 2 diabetes. 相似文献