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11.
This work studies the performance of three commercial ceramic ultrafiltration membranes (ZrO(2)-TiO(2)) treating raw effluent from a textile industry. The effect of crossflow velocity at 3, 4 and 5 m s(-1) as well as membrane characteristics, such as molecular weight cut-off (30, 50 and 150 kDa), on process performance were studied. Experiments were carried out in concentration mode in order to observe the effect of volume reduction factor simultaneously. Results showed a combined influence of both crossflow velocity and molecular weight cut-off on flux performance. TOC and COD removals up to 70% and 84% respectively were reached. On the other hand, almost complete color (>97%) and turbidity (>99%) removals were achieved for all the membranes and operating conditions.  相似文献   
12.
In this paper, consistency is understood in the standard way, i.e. as the absence of a contradiction. The basic constructive logic BKc4, which is adequate to this sense of consistency in the ternary relational semantics without a set of designated points, is defined. Then, it is shown how to define a series of logics by extending BKc4 up to minimal intuitionistic logic. All logics defined in this paper are paraconsistent logics.  相似文献   
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Shiftwork involving early morning starts and night work can affect both sleep and fatigue. This study aimed to assess the impact of different rostering schedules at an Australian mine site on sleep and subjective sleep quality. Participants worked one of four rosters;
4 × 4 (n = 14) 4D4O4N4O
7 × 4 (n = 10) 7D4O7N40
10 × 5 (n = 17) 5D5N50
14 × 7 (n = 12) 7D7N70
Sleep (wrist actigraphy and sleep diaries) was monitored for a full roster cycle including days off. Total sleep time (TST) was longer on days off (7.0 ± 1.9) compared to sleep when on day (6.0 ± 1.0) and nightshifts (6.2 ± 1.6). Despite an increase in TST on days off, this may be insufficient to recover from the severe sleep restriction occurring during work times. Restricted sleep and quick shift-change periods may lead to long-term sleep loss and associated fatigue.  相似文献   
15.
?ukasiewicz presented two different analyses of modal notions by means of many-valued logics: (1) the linearly ordered systems ?3,..., Open image in new window ,..., \(\hbox {L}_{\omega }\); (2) the 4-valued logic ? he defined in the last years of his career. Unfortunately, all these systems contain “?ukasiewicz type (modal) paradoxes”. On the other hand, Brady’s 4-valued logic BN4 is the basic 4-valued bilattice logic. The aim of this paper is to show that BN4 can be strengthened with modal operators following ?ukasiewicz’s strategy for defining truth-functional modal logics. The systems we define lack “?ukasiewicz type paradoxes”. Following Brady, we endow them with Belnap–Dunn type bivalent semantics.  相似文献   
16.
The present study examined spatial and nonspatial learning in adult Tg2576 mice. Transgenic mice were impaired in acquisition of a T-maze forced-choice alternation task. However, mutant mice were as sensitive as control mice to the introduction of retention intervals and proactive interference, and this suggested that short-term memory processes were intact in Tg2576 mice. Probe trials revealed that the Tg2576 mice did not use an allocentric strategy to navigate to the goal arm. However, mutant mice acquired an intramaze brightness discrimination, a simple room discrimination, and a contextual biconditional left-right discrimination in a T maze. Results suggest that Tg2576 mice are able to process both intramaze and extramaze stimuli but are impaired in forming an allocentric representation of their environment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
17.
Preexisting pesticide degradates are a concern for pesticide biomonitoring studies as exposure to them may result in overestimation of pesticide exposure. The purpose of this research was to determine whether there was significant formation and movement, of pesticide degradates over a 5‐week period in a controlled indoor setting after insecticide application. Movement of the pesticides during the study was also evaluated. In a simulated crack and crevice application, commercially available formulations of fipronil, propoxur, cis/trans‐permethrin, and cypermethrin were applied to a series of wooden slats affixed to the wall in one room of an unoccupied test house. Floor surface samples were collected through 35 days post‐application. Concentrations of the pesticides and the following degradates were determined: 2‐iso‐propoxyphenol, cis/trans 3‐(2,2‐dichlorovinyl)‐3‐3‐dimethyl‐(1‐cyclopropane) carboxylic acid, 3‐phenoxybenzoic acid, fipronil sulfone, fipronil sulfide, and fipronil desulfinyl. Deltamethrin, which had never been applied, and chlorpyrifos, which had been applied several years earlier, and their degradation products, cis‐3‐(2,2‐dibromovinyl)‐2,2‐dimethylcyclopropane‐1‐carboxylic acid, and, 3,5,6‐trichloro‐2‐pyridinol, respectively, were also measured. Propoxur was the only insecticide with mass movement away from the application site. There was no measurable formation or movement of the degradates. However, all degradates were present at low levels in the formulated product. These results indicate longitudinal repetitive sampling of indoor degradate levels during short‐term studies, is unnecessary.  相似文献   
18.
Prostate cancer (PCa) is globally the second most diagnosed cancer type and the most common cause of cancer-related deaths in men. Family history of PCa, hereditary breast and ovarian cancer (HBOC) and Lynch syndromes (LS), are among the most important risk factors compared to age, race, ethnicity and environmental factors for PCa development. Hereditary prostate cancer (HPCa) has the highest heritability of any major cancer in men. The proportion of PCa attributable to hereditary factors has been estimated in the range of 5–15%. To date, the genes more consistently associated to HPCa susceptibility include mismatch repair (MMR) genes (MLH1, MSH2, MSH6, and PMS2) and homologous recombination genes (BRCA1/2, ATM, PALB2, CHEK2). Additional genes are also recommended to be integrated into specific research, including HOXB13, BRP1 and NSB1. Importantly, BRCA1/BRCA2 and ATM mutated patients potentially benefit from Poly (ADP-ribose) polymerase PARP inhibitors, through a mechanism of synthetic lethality, causing selective tumor cell cytotoxicity in cell lines. Moreover, the detection of germline alterations in MMR genes has therapeutic implications, as it may help to predict immunotherapy benefits. Here, we discuss the current knowledge of the genetic basis for inherited predisposition to PCa, the potential target therapy, and the role of active surveillance as a management strategy for patients with low-risk PCa. Finally, the current PCa guideline recommendations are reviewed.  相似文献   
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20.
Colorectal carcinoma (CRC) is the third most common cancer. Likewise, it is a disease that has a long survival if it is prematurely detected. However, more than 50% of patients will develop metastases, mainly in the liver (LM-CRC), throughout the evolution of their disease, which accounts for most CRC-related deaths. Treatment it is certainly a controversial issue, since it has not been shown to increase overall survival in the adjuvant setting, although it does improve disease free survival (DFS). Moreover, current chemotherapy combinations are administered based on data extrapolated from primary tumors (PT), not considering that LM-CRC present a very particular tumor microenvironment that can radically condition the effectiveness of treatments designed for a PT. The liver has a particular histology and microenvironment that can determine tumor growth and response to treatments: double blood supply, vascularization through fenestrated sinusoids and the presence of different mesenchymal cell types, among other particularities. Likewise, the liver presents a peculiar immune response against tumor cells, a fact that correlates with the poor response to immunotherapy. All these aspects will be addressed in this review, putting them in the context of the histological growth patterns of LM-CRC, a particular pathologic feature with both prognostic and predictive repercussions.  相似文献   
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