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861.
Pittman CI Pendleton S Bisha B O'Bryan CA Belk KE Goodridge L Crandall PG Ricke SC 《Journal of food science》2011,76(6):M433-M438
Abstract: Escherichia coli O157:H7 and Salmonella spp. are bacterial pathogens often associated with beef, and cause many cases of foodborne illness each year in the United States. During beef slaughter and processing, these bacteria may spread from the hide or intestines to the carcass. The objective of this research was to investigate the use of naturally occurring compounds citrus essential oils (CEOs) extracted from orange peel to reduce or eliminate these pathogens at the chilling stage of processing, or during fabrication. Brisket flats (used to simulate beef subprimals) were spot inoculated with approximately 6 log of surrogate generic E. coli cocktail (previously shown to be identical in growth and survival parameters to E. coli O157:H7 and Salmonella spp.). Following drying, CEOs were applied by spraying at concentrations of 3% and 6% to the surface of different pieces of meat. Treatments were applied using a custom built spray cabinet at 2.07 bar and applied at a rate of 3.79 L/min to replicate commercial practices. The CEOs significantly reduced (P < 0.05) the concentration of E. coli on the brisket flats in comparison to inoculated no spray or water sprayed controls over a period of 90 d, while causing an initial reduction of approximately 1.4 log units. Total aerobic bacteria and psychrotrophic counts were also reduced on uninoculated briskets following treatment. These results indicate that 3% cold‐pressed terpeneless Valencia orange oil could be used as an additional intervention against E. coli O157:H7 and Salmonella spp. at the refrigerated storage stage of processing. Practical Application: CEOs are natural compounds that have been designated as Generally Recognized as Safe (GRAS). They can be used to control Salmonella spp. and E. coli O157:H7 on beef carcasses at the chilling stage. 相似文献
862.
Abstract: Rapid detection of Salmonella in foods is often limited by the high demand for the sensitivity of detection, poor physiological conditions of the target cells, and high concentration of background flora. In this study, the conditions of nonselective enrichment cultivation were modified in order to improve the quantitative detection of heat‐injured Salmonella in minced meat. The effect of the modifications on the recovery was observed by means of RNA‐based sandwich hybridization, which was adjusted for the quantification of Salmonella enterica 23S rRNA in crude cell extracts. The supplementation of buffered peptone water with the enzyme‐controlled substrate delivery system EnBase‐Flo® and ferrioxamine E was shown to improve the recovery of cells in both single strain cultures and in the presence of minced meat. The presented results can be used for the development of more efficient enrichment cultivation media for faster detection of food borne Salmonella. 相似文献
863.
A total of 39 Salmonella enterica serovar Saintpaul strains from imported seafood, pepper and from environmental and clinical samples were analyzed for the presence of virulence genes, antibiotic resistance, plasmid and plasmid replicon types. Pulsed-field gel electrophoresis (PFGE) fingerprinting using the XbaI restriction enzyme and plasmid profiling were performed to assess genetic diversity. None of the isolates showed resistance to ampicillin, chloramphenicol, gentamicin, kanamycin, streptomycin, sulfisoxazole, and tetracycline. Seventeen virulence genes were screened for by PCR. All strains were positive for 14 genes (spiA, sifA, invA, spaN, sopE, sipB, iroN, msgA, pagC, orgA, prgH, lpfC, sitC, and tolC) and negative for three genes (spvB, pefA, and cdtB). Twelve strains, including six from clinical samples and six from seafood, carried one or more plasmids. Large plasmids, sized greater than 50 kb were detected in one clinical and three food isolates. One plasmid was able to be typed as IncI1 by PCR-based replicon typing. There were 25 distinct PFGE-XbaI patterns, clustered to two groups. Cluster A, with 68.5% similarity mainly consists of clinical isolates, while Cluster C, with 67.6% similarity, mainly consisted of shrimp isolates from India. Our findings indicated the genetic diversity of S. Saintpaul in clinical samples, imported seafood, and the environment and that this serotype possesses several virulent genes and plasmids which can cause salmonellosis. 相似文献
864.
SPR生物传感器快速检测沙门氏菌研究初探 总被引:6,自引:0,他引:6
使用集成化手持式SpreetaTM SPR传感器快速检测沙门氏菌,利用亲和素-生物素系统保证检测的准确性;利用沙门氏菌抗体的免疫吸附反应,保证结果的特异性;并引入复合抗体作为第二抗体以扩大检测的响应信号,检测到鼠伤寒沙门氏菌的浓度为105cfu/mL,整个检测过程在1h内完成,从一定程度实现了食品中病原微生物的快速检测。 相似文献
865.
Li-Zhen Deng Arun S. Mujumdar Sriram K. Vidyarthi Jinwen Xu Magdalena Zielinska 《Critical reviews in food science and nutrition》2020,60(15):2481-2508
Abstract With a growing demand for safe, nutritious, and fresh-like produce, a number of disinfection technologies have been developed. This review comprehensively examines the working principles and applications of several emerging disinfection technologies. The chemical treatments, including chlorine dioxide, ozone, electrolyzed water, essential oils, high-pressure carbon dioxide, and organic acids, have been improved as alternatives to traditional disinfection methods to meet current safety standards. Non-thermal physical treatments, such as UV-light, pulsed light, ionizing radiation, high hydrostatic pressure, cold plasma, and high-intensity ultrasound, have shown significant advantages in improving microbial safety and maintaining the desirable quality of produce. However, using these disinfection technologies alone may not meet the requirement of food safety and high product quality. Several hurdle technologies have been developed, which achieved synergistic effects to maximize lethality against microorganisms and minimize deterioration of produce quality. The review also identifies further research opportunities for the cost-effective commercialization of these technologies. 相似文献
866.
Salmonella infantis and Escherichia coli multiplied to varying degrees during the fermentation of unacidified horsebean, pea and chickpea tempeh. Active mycelial growth on the beans resulted in a sharp increase in pH. This was always accompanied by a sharp increase in the growth rate of the test organisms. Acidification of the beans during soaking decreased the growth rate of the test organisms only until active mycelial growth started. Inoculation of cooked beans with Lactobacillus plantarum resulted in a complete inhibition of E coli in unacidified and acidified chickpea tempeh and acidified pea tempeh. Marked inhibition of E coli was also noted in unacidified pea tempeh and acidified horsebean tempeh. S infantis was also completely inhibited by L plantarum in unacidified and acidified chickpea tempeh. In pea and horsebean tempeh, counts of S infantis were always lower in Lactobacillus-inoculated fermenting beans than in the control. Beside the pH, undissociated acids and other substances produced by L plantarum may be inhibitory to the test organisms. The use of L plantarum may be considered for the control of pathogens during commercial-scale tempeh production. 相似文献
867.
目的用PFGE方法绘制不同血清型的沙门菌指纹图谱,并且进行同源性分析。方法首先将从食品中检测出6中不同血清型的沙门菌菌株制成琼脂模块,再提取菌株的DNA,用限制性内切酶XbaⅠ对细菌DNA进行酶切,用Bio-radCHEPMAPPER绘制出菌株的PFGE指纹图谱,最后用QuantityOneTM图像分析软件进行同源性分析。结果所有的菌株的同源性均用相似性系数(矩阵)和百分数表示。结论用PFGE绘制菌株的指纹图再用QuantityOneTM图像分析软件进行分析,是确定食源性致病菌沙门菌同源性的一种有效的方法。 相似文献
868.
In our studies of structure-activity relationships, four aminonitrophenol isomers and eleven derivatives of 3-amino-4-nitrophenol and 4-amino-3-nitrophenol were tested for their ability to induce mutations in Salmonella typhimurium strains TA1535, TA100, TA1537, TA1538 and TA98. In the presence of an Aroclor-1254-induced rat-liver microsomal activation system (S9mix), 4-N- β -hydroxyethylamino-3-nitroanisole and (4-amino-3-nitro) phenoxyethanol were mutagenic in several of these strains. The compounds 3-amino-4-nitrophenol, 3-N-methylamino-4-nitrophenol, 3-N-β-hydroxyethylamino-4-nitrophenol, 3-amino-4-nitroanisole, 3-N-methylamino-4-nitroanisole, 3-N- β -hydroxyethylamino-4-nitroanisole, (3-amino-4-nitro)phenoxyethanol, (3-methylamino-4-nitro)phenoxyethanol, (3-N- β -hydroxyethylamino-4-nitro)phenoxyethanol, 4-amino-3-nitrophenol and 4-N- β -hydroxyethylamino-3-nitrophenol were inactive, both in the presence and in the absence of S9 mix. In contrast to the results with 3-amino-4-nitrophenol and 4-amino-3-nitrophenol, which were negative, the isomers 2-amino-4-nitrophenol and 2-amino-5-nitrophenol were found to be mutagenic. These results on mutagenic and non-mutagenic aminonitrophenols and their derivatives suggest that the occurrence of mutagenic activity among these compounds depends on the nature of the substituent chemical groups and their position in the molecular structure of the compounds.
Aminonitriphenols: relation structure-activité 相似文献
Aminonitriphenols: relation structure-activité 相似文献
869.
为检测沙门菌在本市食品中的污染和耐药情况,采集各类食品样品303件,经增菌后通过特异的免疫磁珠(IMS)吸附并接种XLD平板分离沙门菌.分离的菌株按年度分成2组,分别以改良K-B法测试对28种抗生素的耐药性.在303件样品中检出87件阳性,总阳性率28.71%.分离到的112株沙门菌以德比、肠炎血清型占优势.肉类制品的阳性率40.20%(82/204)明显高于其它食品,共分离出107株沙门菌(107/112,95.54%).菌株耐药率在2年中有显著改变的抗生素有环丙沙星、复方新诺明、妥布霉素、二甲胺四环素、氯霉素和链霉素.耐10种以上抗生素的多重耐药株有12株(12/112,10.71%),有4株头孢哌酮耐药株.IMS用于食品中沙门菌的分离效果较好.结果显示耐环丙沙星和多重耐药菌株的增多说明加强食源性沙门菌耐药监测的重要性。 相似文献
870.
R. Edenharder Claudia Speth Michaela Decker Karl Ludwig Platt 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1998,207(6):464-471
Nine naphthoquinones, 19 anthraquinones, and nine structurally related monoketonic compounds such as anthrone, xanthone,
etc., inhibited mutagenicity induced by 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) in Salmonella typhimurium TA 98 in the presence of rat liver S9 with distinct structure-activity relationships. A carbonyl function was a prerequisite
for antimutagenicity while, in general, anthraquinones (IC50 values: 2.3–>213 nmol/ml top agar) were more potent antimutagens than structurally related monoketonic compounds (IC50 values: 25.3–94.9 nmol/ml top agar) and naphthoquinones (IC50 values: 3.7–90.7 nmol/ml top agar). The parent compounds and methyl substituted derivatives were already the most potent while
introduction of polar substituents such as COOH and SO3H considerably reduced antimutagenicity. Introduction of OH functions had equivocal effects: with increasing numbers, antimutagenic
potencies were concomitantly reduced; however, anthraflavic acid, chrysazin, quinizarin, and especially 5,8-dihydroxy-1,4-naphthoquinone
were more potent than the parent compounds. The patterns of inhibition by quinones of 7-ethoxyresorufin-O-dealkylase activities in rat liver microsomes, linked to cytochrome P-450-dependent oxidation of IQ to N-hydroxy-IQ (N-OH-IQ), were in general identical with those obtained in the Salmonella/reversion assay except for chrysophanic acid, emodin, and some naphthoquinones which were very potent in this assay (IC50: 0.20–45.0 μM). On the other hand, mutagenicity of N-OH-IQ in S. typhimurium TA 98NR was not inhibited by nonpolar quinones (except 1,4-naphthoquinone) but rather by polar compounds and especially by
hydroxyquinones (IC50 values: 5.3–106.7 nmol/ml top agar or not reached). Inhibition of mutagenic activities of IQ, 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline, 2-amino-6-methyldipyrido[1,2-a:3′,2′-d]imidazole, and 3-amino-1-methyl-5H-pyrido[4,3-b]indole by chrysazin, chrysophanic acid, physicon, and purpurin varied, but no clearcut structure-activity relationships of
the mutagens were observed.
Received: 29 May 1998 相似文献