首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   107篇
  免费   5篇
化学工业   29篇
金属工艺   1篇
建筑科学   1篇
能源动力   1篇
轻工业   36篇
石油天然气   3篇
无线电   3篇
一般工业技术   6篇
冶金工业   12篇
原子能技术   1篇
自动化技术   19篇
  2023年   1篇
  2022年   1篇
  2021年   3篇
  2019年   2篇
  2018年   4篇
  2017年   1篇
  2016年   2篇
  2015年   9篇
  2014年   6篇
  2013年   11篇
  2012年   6篇
  2011年   6篇
  2010年   7篇
  2009年   6篇
  2008年   6篇
  2007年   2篇
  2006年   3篇
  2005年   3篇
  2004年   5篇
  2002年   1篇
  2000年   4篇
  1999年   1篇
  1998年   9篇
  1997年   4篇
  1996年   3篇
  1995年   1篇
  1994年   1篇
  1993年   1篇
  1990年   1篇
  1978年   1篇
  1976年   1篇
排序方式: 共有112条查询结果,搜索用时 25 毫秒
31.
To be able to diagnose systemic candidiasis (SC) and to predict outcomes in SC patients are still challenging tasks for physicians. Previous proteomic studies suggest that anti-Candida methionine synthase (Met6p) IgG antibodies may be a candidate marker for SC. To evaluate their reliability for diagnosis, prognosis and risk stratification in SC, we developed a generic prototype strategy for their measurement in SC. Receiver-operating-characteristic curve analyses revealed a high diagnostic accuracy for this prototype format, which was slightly better to that for the widely used Western blot assays. Multivariate logistic-regression models showed a positive association between serum anti-Met6p IgG antibody levels and SC risk that was independent from established SC risk factors and other baseline variables. After adjusting for and stratifying according to known prognostic factors, a significant trend toward a lower two-month mortality risk with increasing levels was evidenced in SC patients at presentation. We conclude that these antibodies may be useful in discriminating SC from non-SC patients and determining risk stratification in SC. These may also confer protection against SC and be valuable for the design of future immunotherapies. Furthermore, our prototype format has the potential to make impact on other infectious diseases, cancers, allergies or autoimmune disorders.  相似文献   
32.
In this work experimental data for the refractive index on mixing for butyl acetate + (toluene, ethylbenzene, p-xylene, isopropylbenzene, butylbenzene, isobutylbenzene, mesitylene, or t-butylbenzene) binary mixtures, and some computed derived properties, as a function of temperature, are presented. The mixtures show a clear expansive trend for the highest molar mass compounds. Values of measured properties were compared with results obtained by semiempirical relations and equations of state with simple mixing rules. Accurate results were obtained with the latter, and such parameters could be used in the prediction of multicomponent refractive indices or other thermodynamic properties using standard thermodynamic expressions  相似文献   
33.
The Candida albicans CDR1 gene encodes a member of the ABC-type family of multidrug transporters which has been shown to be involved in azole resistance. Using an in-frame gene fusion between the CDR1 open reading frame and the green fluorescent protein allele yEGFP3, an optimized derivative for its use in C. albicans, we show here how the CDR1-yEGFP3 gene expression is induced in response to azoles as well as to other structurally unrelated drugs like cycloheximide. Moderate increases were observed for calcofluor, canavanine, 5′-fluorcytosine, cilofungin and caffeine, while no induction was found for the antifungals benomyl and amphotericin B or hydrogen peroxide at subinhibitory concentrations. The use of confocal microscopy enabled us to localize the Cdr1p fusion protein at the cell periphery, thus suggesting a cytoplasmic membrane localization. These results suggest deregulation of CDR1 gene as a putative mechanism for the generation of azole resistance in this clinically important pathogenic fungus. © 1998 John Wiley & Sons, Ltd.  相似文献   
34.
We describe a case of double outlet right ventricle with subaortic ventricular septal defect and pulmonary stenosis treated successfully with cardiopulmonary bypass. We consider the clinical history and angiocardiographic and surgical findings of this rare anomaly. We stress the difficulties of reconstruction of the outflow tract of the right ventricle, because of the anomalous pathway of the right coronary artery, the posterior situation of the pulmonary artery, and the abnormal anatomy present in the outflow tract of the right ventricle.  相似文献   
35.
36.
The authors aimed to study the deasphalting process on laboratory scale through the design and development of a supercritical extraction experimental unit. The experimental unity used in tests is composed by a pump, an extractor with useful volume of 3 L and one separator vessel. Extractions in supercritical condition were carried out using petroleum residue (vacuum residuum) as feedstock and water as solvent. Temperature and pressure were manipulated to maintain the solvent in the required conditions, thus facilitating the extraction process and avoiding sharp changes in the system. In both phases, the products in the deasphalted oil stream present adequate characteristics for the production of lubricant oils and those in the asphalt residue stream present an elevated concentration of asphalt molecules.  相似文献   
37.
The impact of acid incorporation (acetic + lactic, 0.5%) into rice starch-based doughs enriched with different proteins (egg albumin, calcium caseinate, pea protein and soy protein isolates) at different doses (0, 5 and 10%) has been investigated on dough viscoelastic and pasting profiles. Oscillatory (stress and frequency sweeps) and creep-recovery tests were used to characterize the fundamental viscoelastic behaviour of the doughs, and thermomechanical assays were performed to assess dough viscometric performance. Supplementation of gluten-free doughs with proteins from vegetal sources led to more structured dough matrices (higher viscoelastic moduli and steady viscosities, and lower tan δ, instantaneous and retarded elastic compliances) effect being magnified with protein dose. Acid addition decreased these effects. Incorporation of proteins from animal source resulted in different viscoelastic behaviours according to the protein type, dosage and acidification, especially for casein. Acidification conferred lower dough deformation and notably higher steady viscosity and viscoelastic moduli for 5 %-casein-added dough. Protein-acid interaction favoured higher viscosity profiles, particularly for doughs with proteins of vegetable origin and lower dosage. Dough acidification decreased the pasting temperatures and the amylose retrogradation. Acidification of protein-enriched rice-starch doughs allowed manipulation of its viscometric and rheological properties which is of relevant importance in gluten-free bread development.  相似文献   
38.
Twenty-three children who had unilateral surgery for idiopathic clubfeet underwent gait analysis and isokinetic muscle-strength testing at an average of 10 years after surgical release. Ankle sagittal-plane kinematics were disturbed in 20 clubfeet. Fifteen children had an internal foot-progression angle. Genu valgum and knee hyperextension were common. Plantarflexion power was decreased by 23% on the side of surgery (p = 0.00005). Quadriceps weakness (defined as a decrease in strength >10% of the nonoperated-on limb's strength) was seen in nine of 22 operated-on limbs and hamstring weakness in eight of 22. Gastrocsoleus weakness exceeded 10% in 16 of 21 clubfeet. Average weakness of the gastrocsoleus was 27% (p < 0.05). Ten-year analysis of children treated with clubfoot releases revealed disturbances in ankle motion and strength. Loss of plantarflexion power and gastrocsoleus strength can be predicted by Achilles tendon lengthening. Knee kinematic abnormalities and weakness also were seen. These abnormalities produce functional difficulties in gait and may lead to degenerative changes later.  相似文献   
39.
An analysis of different thermodynamic properties as a function of temperature provides valuable information about their characteristics. The ultrasonic velocity of the ternary mixtures ethanol+water+1-pentanol at the range 288.15–323.15 K and atmospheric pressure, has been measured over the whole concentration range. The experimental ultrasonic velocities have been analysed in terms of different theoretical models, an adequate agreement between the experimental and predicted values both in magnitude and sign being obtained, despite the high non-ideal trend and partial miscibility of the ternary mixture studied in this work. The obtained experimental values indicate varying extent of interstitial accommodation among unlike molecules as a function of steric hindrance attending to 1-pentanol as key component and as a function of hydrogen bond and temperature attending to ethanol as key component.  相似文献   
40.
The nucleotide sequence of the 3.5-kb right junction fragment of the streptococcal conjugative transposon Tn5252 was obtained. The DNA fragment was found to carry four putative genes one of which displayed a high degree of similarity to prokaryotic 5C-cytosine methyltransferases carrying multiple sequence specificities. No cognate endonuclease gene was detected in the sequenced DNA. Purified methylase polypeptide synthesized in a T7 promoter-controlled overexpression system was found to lack methylase activity while the cell extracts of host cells containing the recombinant plasmid carrying the methylase gene were active. In vivo mutations in the methylase gene did not seem to affect the transferability of the element.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号