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21.
The aim was to investigate the prevalence of non-alcoholic steatohepatitis (NASH) and risk factors for hepatic fibrosis in morbidly obese patients submitted to bariatric surgery. This retrospective study recruited all patients submitted to bariatric surgery from January 2007 to December 2012 at a reference attendance center of Southern Brazil. Clinical and biochemical data were studied as a function of the histological findings of liver biopsies done during the surgery. Steatosis was present in 226 (90.4%) and NASH in 176 (70.4%) cases. The diagnosis of cirrhosis was established in four cases (1.6%) and fibrosis in 108 (43.2%). Risk factors associated with NASH at multivariate analysis were alanine aminotransferase (ALT) >1.5 times the upper limit of normal (ULN); glucose ≥ 126 mg/dL and triglycerides ≥ 150 mg/dL. All patients with ALT ≥1.5 times the ULN had NASH. When the presence of fibrosis was analyzed, ALT > 1.5 times the ULN and triglycerides ≥ 150 mg/dL were risk factors, furthermore, there was an increase of 1% in the prevalence of fibrosis for each year of age increase. Not only steatosis, but NASH is a frequent finding in MO patients. In the present study, ALT ≥ 1.5 times the ULN identifies all patients with NASH, this finding needs to be further validated in other studies. Moreover, the presence of fibrosis was associated with ALT, triglycerides and age, identifying a subset of patients with more severe disease.  相似文献   
22.
The aim of this work was to investigate the mechanism of action of 2‐ferrocenyl‐1,1‐diphenylbut‐1‐ene ( 1 ) on HL‐60 human leukemia cells. While inactive against noncancerous cells, 1 provoked a concentration‐dependent decrease in viable tumor cells, primarily via apoptosis, as evidenced by analysis of cell morphology, activation of caspases 3 and 7, increased DNA fragmentation, and externalization of phosphatidylserine. Necrosis was observed only at the highest tested concentration (4 μM ). Compound 1 interfered with the cell cycle, causing an accumulation of cells in the G1/G0 phase. Interaction of 1 with dsDNA and ssDNA was observed by differential pulse voltammetry and confirmed by hyperchromicity in the UV/Vis spectra of dsDNA, with an interaction constant of 2×104 M ?1. Both the organic analogue 1,1,2‐triphenylbut‐1‐ene ( 2 ) and ferrocene were inactive against cancer and noncancer cell lines and did not react with DNA. These results reinforce the idea that the hybrid strategy of conjugating ferrocene to the structure of tamoxifen derivatives is advantageous in finding new substances with antineoplastic activity.  相似文献   
23.
Highly permeable cellular anorthite glass ceramics with porosity of ∼95% were obtained by a simple replication technique using near-stoichiometric glass powders and a polymeric foam as sacrificial template material. Impacts of sintering conditions and additions of minor constituents, respectively, on microstructural evolution and resulting macroscopic properties of the derived foams were investigated by X-ray diffraction, scanning electron microscopy (SEM), differential thermal analysis and X-ray microcomputer tomography. Apparent activation energies of crystallization and the Avrami coefficient were estimated from nonisothermal crystallization experiments to evaluate the impact of titania and zirconia, respectively, as potential nucleation agents. Consistent with SEM analyses, it was found that crystal growth occurs in two dimensions. While TiO2 primarily acts on the viscosity of the precursor glass and, thus, on the process of sintering by viscous flow, ZrO2 is found to exhibit at least some nucleation efficiency. As compared with sintering of ceramic powders and solid-state reactions in general, the glass ceramic route enables significant reduction in sintering time and temperature.  相似文献   
24.
Increasing reports of multidrug-resistant malaria parasites urge the discovery of new effective drugs with different chemical scaffolds. Protein kinases play a key role in many cellular processes such as signal transduction and cell division, making them interesting targets in many diseases. Protein kinase 7 (PK7) is an orphan kinase from the Plasmodium genus, essential for the sporogonic cycle of these parasites. Here, we applied a robust and integrative artificial intelligence-assisted virtual-screening (VS) approach using shape-based and machine learning models to identify new potential PK7 inhibitors with in vitro antiplasmodial activity. Eight virtual hits were experimentally evaluated, and compound LabMol-167 inhibited ookinete conversion of Plasmodium berghei and blood stages of Plasmodium falciparum at nanomolar concentrations with low cytotoxicity in mammalian cells. As PK7 does not have an essential role in the Plasmodium blood stage and our virtual screening strategy aimed for both PK7 and blood-stage inhibition, we conducted an in silico target fishing approach and propose that this compound might also inhibit P. falciparum PK5, acting as a possible dual-target inhibitor. Finally, docking studies of LabMol-167 with P. falciparum PK7 and PK5 proteins highlighted key interactions for further hit-to lead optimization.  相似文献   
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26.
IP multihoming is a networking concept with a deceptively simple definition in theory. In practice, however, multihoming has proved difficult to implement and optimize for. Moreover, it is a concept, which, once adopted in the core Internet architecture, has a significant impact on operation and maintenance. A trivial definition of multihoming would state that an end-node or an end-site has multiple first-hop connections to the network. In this paper, we survey and summarize in a comprehensive manner recent developments in IP multihoming. After introducing the fundamentals, we present the architectural goals and system design principles for multihoming, and review different approaches. We survey multihoming support at the application, session, transport, and network layers, covering all recent proposals based on a locator/identifier split approach. We critically evaluate multihoming support in these proposals and detail recent developments with respect to multihoming and mobility management.  相似文献   
27.
The purpose of this research is to explore the principle of the man-object relationship to identify the issues shown when handling packaging and emphasizing the usability aspect. For that, the theoretical reference of the research involves the analysis of the parameters according to the aspects that involve the use interactions of packaging in agreement with the definition and scientific concepts of ergonomics, allied to the development of product projects, discussing forms, handling, load transportation and the support of the product. Therefore, improperly handling of the packaging may cause damages to the products and even potential accidents. Coding and decoding are significant to facilitate the use recognition within the individual's repertoire. The packaging, within the macro-ergonomics universe, may be the object of ergonomics, whose contribution to solve problems is related to labor activities, by dealing with packaging, transportation and load resulting from the man-object interaction. The incorrect identification of information may lead to problems of interpretation and misuse, from the handling to the disposal of packaging. For this reason, this research suggests the adjustment of the man-object interface which may lead users to make mistakes regarding use and important choices, through adequate handling actions.  相似文献   
28.
The first objective of this study was to confirm that 4 days of head-down tilt (HDT) were sufficient to induce orthostatic intolerance, and to check if 4 days of physical confinement may also induce orthostatic intolerance. Evidence of orthostatic intolerance during tilt-up tests was obtained from blood pressure and clinical criteria. The second objective was to quantify the arterial and venous changes associated with orthostatic intolerance and to check whether abnormal responses to the tilt test and lower body negative pressure (LBNP) may occur in the absence of blood pressure or clinical signs of orthostatic intolerance. The cerebral and lower limb arterial blood flow and vascular resistance, the flow redistribution between these two areas, and the femoral vein distension were assessed during tilt-up and LBNP by ultrasound. Eight subjects were given 4 days of HDT and, 1 month later, 4 days of physical confinement. Tilt and LBNP test were performed pre- and post-HDT and confinement. Orthostatic intolerance was significantly more frequent after HDT (63%) than after confinement (25%, P < 0.001). Cerebral haemodynamic responses to tilt-up and LBNP tests were similar pre- and post-HDT or confinement. Conversely, during both tilt and LBNP tests the femoral vascular resistances increased less (P < 0.002), and the femoral blood flow reduced less (P < 0.001) after HDT than before HDT or after confinement. The cerebral to femoral blood flow ratio increased less after HDT than before (P < 0.002) but remained unchanged before and after confinement. This ratio was significantly more disturbed in the subjects who did not complete the tilt test. The femoral superficial vein was more distended during post-HDT LBNP than pre-HDT or after confinement (P < 0.01). In conclusion, 4 days of HDT were enough to alter the lower limb arterial vasoconstriction and venous distensibility during tilt-up and LBNP, which reduced the flow redistribution in favour of the brain in all HDT subjects. Confinement did not alter significantly the haemodynamic responses to orthostatic tests. The cerebral to femoral blood flow ratio measured during LBNP was the best predictor of orthostatic intolerance.  相似文献   
29.
Twenty-six Jersey cows were assigned randomly to one of two treatments. Twelve cows received biweekly subcutaneous injection of 500 mg of sometribove, USAN (recombinant methionyl bovine somatotropin), beginning 60 +/- 3 d postpartum and continuing throughout one lactation. Fourteen control animals received injections of placebo carrier. Milk samples were taken biweekly on weeks alternate to injection when differences in milk components were expected to be greatest compared with controls. The milk samples were analyzed for total nitrogen, noncasein nitrogen, and non-protein nitrogen. The average SCC for control and treatment groups was 44,000 +/- 47,000 and 56,000 +/- 65,000. Milk from sometribove-treated cows was significantly lower in total protein (3.92, 4.12%), true protein (3.74, 3.95%), and casein (3.11, 3.34%) than that from control cows on d 8 of the 14 d injection cycle. Casein as a percentage of true protein was lower (83.38, 84.52%), and non-protein nitrogen as a percentage of total nitrogen was higher (4.61, 4.26%) in milk from treated cows. The theoretical yield of Cheddar cheese was ca. .07% less for milk from treated cows than from control cows due to ca. 1% less casein as a percentage of true protein in the former. The differences in nitrogen distribution represent the response during the middle of the injection cycle when milk output was the highest and milk protein the lowest rather than the average response for the injection cycle. The results of the study indicate minimal impact on the cheese manufacturer because in practice milk is commingled from many dairies.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
30.
We investigate from first principles the electronic and transport properties of hybrid organic/silicon interfaces of relevance to molecular electronics. We focus on conjugated molecules bonded to hydrogenated Si through hydroxyl or thiol groups. The electronic structure of the systems is addressed within density functional theory, and the electron transport across the interface is directly evaluated within the Landauer approach. The microscopic effects of molecule-substrate bonding on the transport efficiency are explicitly analyzed, and the oxygen-bonded interface is identified as a candidate system when preferential hole transfer is?needed.  相似文献   
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