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孙湘  张国山 《有色设备》2002,(3):12-14,17
论述了铅始极片生产自动线各机构的工作原理,主要运行参数的分析与选取,该生产线技术先进,经构紧凑合理,指标稳定,运行可靠。  相似文献   
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介绍根据生产稀土的串级萃取工艺要求所设计的一套完整的、能够对流量进行自动检测、调节、显示及参数修改的测控系统。  相似文献   
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The agar dilution MIC method was used to test the activity of cefminox, a beta-lactamase-stable cephamycin, compared with those of cefoxitin, cefotetan, moxalactam, ceftizoxime, cefotiam, cefamandole, cefoperazone, clindamycin, and metronidazole against 357 anaerobes. Overall, cefminox was the most active beta-lactam, with an MIC at which 50% of isolates are inhibited (MIC50) of 1.0 microg/ml and an MIC90 of 16.0 microg/ml. Other beta-lactams were less active, with respective MIC50s and MIC90s of 2.0 and 64.0 microg/ml for cefoxitin, 2.0 and 128.0 microg/ml for cefotetan, 2.0 and 64.0 microg/ml for moxalactam, 4.0 and > 128.0 microg/ml for ceftizoxime, 16.0 and > 128.0 microg/ml for cefotiam, 8.0 and >128.0 microg/ml for cefamandole, and 4.0 and 128.0 microg/ml for cefoperazone. The clindamycin MIC50 and MIC90 were 0.5 and 8.0 microg/ml, respectively, and the metronidazole MIC50 and MIC90 were 1.0 and 4.0 microg/ml, respectively. Cefminox was especially active against Bacteroides fragilis (MIC90, 2.0 microg/ml), Bacteroides thetaiotaomicron (MIC90, 4.0 microg/ml), fusobacteria (MIC90, 1.0 microg/ml), peptostreptococci (MIC90, 2.0 microg/ml), and clostridia, including Clostridium difficile (MIC90, 2.0 microg/ml). Time-kill studies performed with six representative anaerobic species revealed that at the MIC all compounds except ceftizoxime were bactericidal (99.9% killing) against all strains after 48 h. At 24 h, only cefminox and cefoxitin at 4x the MIC and cefoperazone at 8x the MIC were bactericidal against all strains. After 12 h, at the MIC all compounds except moxalactam, ceftizoxime, cefotiam, cefamandole, clindamycin, and metronidazole gave 90% killing of all strains. After 3 h, cefminox at 2 x the MIC produced the most rapid effect, with 90% killing of all strains.  相似文献   
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Bacterial translocation (BT) is defined as the passage of enteric bacteria from the gastrointestinal tract to extraintestinal tissues. Bacterial overgrowth is one of the main promoting factors of BT, which is thought to play an important role in the pathogenesis of sepsis and necrotizing enterocolitis. It is believed that small-bowel colonization is established by bacterial spread through the rectum. Gastric acid is also involved in this process. An experimental study was designed for investigating the effect of gastric acid inhibition with the use of an H2-receptor antagonist on intestinal colonization and BT in newborn rats. Animals were divided into two groups: the ranitidine group (n = 20) received ranitidine 10 mg/kg per day intramuscularly for 5 days; the control group (n = 30) received saline solution. Mesenteric lymph node, spleen, liver, stomach, small bowel/cecum, and large bowel specimens were obtained from each rat 5 days later and gram-negative and -positive aerobic bacteria identified by the use of chocolate and Endo agar. It is concluded that: (1) there was a strong correlation between gastric and small-bowel bacterial colonization in the ranitidine group; (2) no correlation between large-and small-bowel colonization could be demonstrated; and (3) BT occurred only in the ranitidine group.  相似文献   
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综合应用统计分析、预测理论、模式识别、神经网络和专家系统等多项技术,针对德兴铜矿设备状态监测的实际情况。研究设备润滑磨损状态智能分析技术。  相似文献   
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