全文获取类型
收费全文 | 1061篇 |
免费 | 79篇 |
专业分类
电工技术 | 6篇 |
综合类 | 6篇 |
化学工业 | 478篇 |
金属工艺 | 11篇 |
机械仪表 | 8篇 |
建筑科学 | 61篇 |
矿业工程 | 5篇 |
能源动力 | 28篇 |
轻工业 | 188篇 |
水利工程 | 3篇 |
石油天然气 | 3篇 |
无线电 | 53篇 |
一般工业技术 | 148篇 |
冶金工业 | 40篇 |
原子能技术 | 2篇 |
自动化技术 | 100篇 |
出版年
2024年 | 6篇 |
2023年 | 32篇 |
2022年 | 110篇 |
2021年 | 119篇 |
2020年 | 51篇 |
2019年 | 43篇 |
2018年 | 42篇 |
2017年 | 50篇 |
2016年 | 35篇 |
2015年 | 45篇 |
2014年 | 39篇 |
2013年 | 62篇 |
2012年 | 61篇 |
2011年 | 76篇 |
2010年 | 59篇 |
2009年 | 48篇 |
2008年 | 51篇 |
2007年 | 26篇 |
2006年 | 33篇 |
2005年 | 23篇 |
2004年 | 18篇 |
2003年 | 13篇 |
2002年 | 14篇 |
2001年 | 4篇 |
2000年 | 5篇 |
1999年 | 10篇 |
1998年 | 11篇 |
1997年 | 9篇 |
1996年 | 7篇 |
1995年 | 5篇 |
1994年 | 5篇 |
1993年 | 3篇 |
1992年 | 4篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 5篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有1140条查询结果,搜索用时 15 毫秒
21.
Sonia Domingos-Pereira Karthik Sathiyanadan Lenka Polak Jacques-Antoine Haefliger Martina Schmittnaegel Carola H. Ries Patrice Jichlinski Beat Roth Laurent Derr Denise Nardelli-Haefliger 《International journal of molecular sciences》2023,24(1)
Bacillus Calmette-Guérin (BCG) instillations for the treatment of non-muscle-invasive bladder cancer patients can result in significant side effects and treatment failure. Immune checkpoint blockade and/or decreasing tumor-infiltrating myeloid suppressor cells may be alternative or complementary treatments. Here, we have characterized immune cell infiltration and chemoattractant molecules in mouse orthotopic MB49 bladder tumors. Our data show a 100-fold increase in CD45+ immune cells from day 5 to day 9 tumors including T cells and mainly myeloid cells. Both monocytic myeloid-derived suppressor-cells (M-MDSC) and polymorphonuclear (PMN)-MDSC were strongly increased in day 9 tumors, with PMN-MDSC representing ca. 70% of the myeloid cells in day 12 tumors, while tumor associated macrophages (TAM) were only modestly increased. The kinetic of PD-L1 tumor expression correlated with published data from patients with PD-L1 expressing bladder tumors and with efficacy of anti-PD-1 treatment, further validating the orthotopic MB49 bladder-tumor model as suitable for designing novel therapeutic strategies. Comparison of chemoattractants expression during MB49 bladder tumors grow highlighted CCL8 and CCL12 (CCR2-ligands), CCL9 and CCL6 (CCR-1-ligands), CXCL2 and CXCL5 (CXCR2-ligands), CXCL12 (CXCR4-ligand) and antagonist of C5/C5a as potential targets to decrease myeloid suppressive cells. Data obtained with a single CCR2 inhibitor however showed that the complex chemokine crosstalk would require targeting multiple chemokines for anti-tumor efficacy. 相似文献
22.
Solmaz Abdolrahimzadeh Martina Formisano Mariachiara Di Pippo Manuel Lodesani Andrew John Lotery 《International journal of molecular sciences》2022,23(14)
Stargardt disease is the commonest juvenile macular dystrophy. It is caused by genetic mutations in the ABCA4 gene. Diagnosis is not always straightforward, and various phenocopies exist. Late-onset disease can be misdiagnosed with age-related macular disease. A correct diagnosis is particularly critical because of emergent gene therapies. Stargardt disease is known to affect retinal pigment epithelium and photoreceptors. Many studies have also highlighted the importance of the choroid in the diagnosis, pathophysiology, and progression of the disease. The choroid is in an integral relationship with the retinal pigment epithelium and photoreceptors, and its possible involvement during the disease should be considered. The purpose of this review is to analyze the current diagnostic tools for choroidal evaluation and the extrapolation of useful data for ophthalmologists and researchers studying the disease. 相似文献
23.
Martina Casarin Alessandro Morlacco Fabrizio Dal Moro 《International journal of molecular sciences》2022,23(12)
In the case of pediatric urology there are several congenital conditions, such as hypospadias and neurogenic bladder, which affect, respectively, the urethra and the urinary bladder. In fact, the gold standard consists of a urethroplasty procedure in the case of urethral malformations and enterocystoplasty in the case of urinary bladder disorders. However, both surgical procedures are associated with severe complications, such as fistulas, urethral strictures, and dehiscence of the repair or recurrence of chordee in the case of urethroplasty, and metabolic disturbances, stone formation, urine leakage, and chronic infections in the case of enterocystoplasty. With the aim of overcoming the issue related to the lack of sufficient and appropriate autologous tissue, increasing attention has been focused on tissue engineering. In this review, both the urethral and the urinary bladder reconstruction strategies were summarized, focusing on pediatric applications and evaluating all the biomaterials tested in both animal models and patients. Particular attention was paid to the capability for tissue regeneration in dependence on the eventual presence of seeded cell and growth factor combinations in several types of scaffolds. Moreover, the main critical features needed for urinary tissue engineering have been highlighted and specifically focused on for pediatric application. 相似文献
24.
Kai Yao Siqi Li Zhiliang Liu Yiran Ying Petr Dvo?ák Linfeng Fei Tomá? ?ikola Haitao Huang Peter Nordlander Alex K.-Y.Jen Dangyuan Lei 《光:科学与应用(英文版)》2021,(11):2233-2244
The deep-level traps induced by charged defects at the grain boundaries (GBs) of polycrystalline organic–inorganic halide perovskite (OIHP) films serve as major... 相似文献
25.
Martina Halasova Zdenek Chlup Adam Strachota Martin Cerny Ivo Dlouhy 《Journal of the European Ceramic Society》2012,32(16):4489-4495
The presented work describes mechanical properties of materials prepared by the pyrolysis of polysiloxane resins. The polymeric precursors have different chemical composition. Materials under investigation are predetermined for high temperature resistant applications usually in composite form, i.e. accompanied by some reinforcement. Instrumented hardness tests were employed for material characterisation. The Vickers hardness, Martens hardness and indentation elastic modulus were the key parameters, determined either from the standard optical technique or load–indentation depth curves. The influence of mechanical properties on the monomers ratio was established. The exposition to the temperature between 1200 °C and 1500 °C in air was applied to observe damage caused by these severe conditions. 相似文献
26.
27.
28.
José M. León Blanco Pedro L. González-R Carmen Martina Arroyo García María José Cózar-Bernal Marcos Calle Suárez David Canca Ortiz 《Drug development and industrial pharmacy》2018,44(1):135-143
This work was aimed at determining the feasibility of artificial neural networks (ANN) by implementing backpropagation algorithms with default settings to generate better predictive models than multiple linear regression (MLR) analysis. The study was hypothesized on timolol-loaded liposomes. As tutorial data for ANN, causal factors were used, which were fed into the computer program. The number of training cycles has been identified in order to optimize the performance of the ANN. The optimization was performed by minimizing the error between the predicted and real response values in the training step. The results showed that training was stopped at 10?000 training cycles with 80% of the pattern values, because at this point the ANN generalizes better. Minimum validation error was achieved at 12 hidden neurons in a single layer. MLR has great prediction ability, with errors between predicted and real values lower than 1% in some of the parameters evaluated. Thus, the performance of this model was compared to that of the MLR using a factorial design. Optimal formulations were identified by minimizing the distance among measured and theoretical parameters, by estimating the prediction errors. Results indicate that the ANN shows much better predictive ability than the MLR model. These findings demonstrate the increased efficiency of the combination of ANN and design of experiments, compared to the conventional MLR modeling techniques. 相似文献
29.
30.
Mathilde H. Josefsen Lise Bonnichsen Jonas T. Larsson Eva M. Nielsen Martina Fricker Monica Ehling-Schulz Jeffrey Hoorfar Laurids S. Christensen 《Food Analytical Methods》2012,5(5):980-987
Discriminatory and robust typing methods are needed to improve the understanding of the dynamics of food-borne Campylobacter infections and epidemiology in primary animal production. To evaluate the strain discriminatory potential of typing methods, flaA short variable region (SVR) sequencing and Fourier transform infrared (FTIR) spectroscopy were applied on a collection of 102 epidemiologically related and unrelated Campylobacter jejuni strains. Previous application of FTIR spectroscopy for subtyping of Campylobacter has been limited. A subset of isolates, initially discriminated by flaA SVR sequencing, were further subjected to multilocus sequence typing (MLST). It was found that flaA SVR sequencing had a slightly higher discriminatory power than FTIR spectroscopy, based on the Simpson diversity index. The clustering of strains indicated that FTIR spectroscopy is indeed a suitable method for discrimination of Campylobacter. The isolates were assigned to six clusters based on flaA SVR sequences and nine clusters based on the FTIR spectroscopy profiles. Furthermore, the cluster analysis of flaA SVR sequences, MLST, and FTIR spectroscopy profiles showed a high degree of congruence, assigning the isolates to similar cluster structures. In conclusion, FTIR spectroscopy can be applied for subtyping of Campylobacter, and the high discriminatory potential of both flaA SVR sequencing and FTIR spectroscopy render them suitable screening methods for large numbers of strains. 相似文献