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1.
氟喹诺酮类药物(FQs)耐药性产生的分子机制   总被引:3,自引:0,他引:3  
随着氟喹诺酮类药物的广泛使用,细菌对该类药物产生耐药性日趋严重,这引起了国内外的高度重视。本文就FQs耐药性产生的分子机制,即药靶的改变,药物在菌体内蓄积浓度下降及由质粒介导的耐药等机制做了综述。  相似文献   

2.
氟喹诺酮类药物耐药性的研究进展   总被引:1,自引:0,他引:1  
随着氟喹诺酮类药物(FQs)在兽医和人医临床上的广泛使用,细菌对该类药物的耐药性日趋严重,这引起了国内外的高度重视。本文就FQs耐药性的研究进展,包括耐药性的发展,耐药性产生的分子机制即靶酶的改变,药物在菌体内蓄积浓度下降,以及由质粒介导的耐药等机制做了综述。  相似文献   

3.
喹诺酮类药物耐药性现状与分析   总被引:3,自引:1,他引:2  
喹诺酮类药物是一类合成广谱抗菌药,尤其是近年来合成的氟喹诺酮类药物,因其使用剂量低、抗菌谱广、疗效好而被广泛应用于临床。然而,随着临床用量的增加和使用范围的不断扩大,细菌耐药性问题也随之出现,并且发展迅速。国际社会也已意识到这一问题的严重性。本文介绍了喹诺酮类药物耐药性的发展现状及由此产生的严重后果。对其耐药性产生的机制,即基因突变、细菌的主动排药系统及细菌的获得耐药性进行了分析,并提出一些相关对策。  相似文献   

4.
《畜牧与兽医》2016,(11):120-123
抗菌药物如氟喹诺酮类、四环素类、大环内酯类、杆菌肽类和氨基糖苷类等广泛用于细菌所致疾病的治疗,然而抗菌药物的广泛应用导致药物对细菌选择性压力不断增加,细菌耐药性也日益严重。尽管细菌耐药性和毒力基因发挥的作用不同,但是细菌对抗菌药物产生耐药性会对细菌的毒力具有一定的影响。本文将对细菌对氟喹诺酮类、四环素类、大环内酯类、杆菌肽类和氨基糖苷类药物耐药后对毒力的影响进行综述。  相似文献   

5.
金黄色葡萄球菌氟喹诺酮的耐药抑制剂研究进展   总被引:1,自引:0,他引:1  
金黄色葡萄球菌是引起人和动物感染的一种重要病原菌,它可以对氟喹诺酮等多种抗菌药物产生耐药性,严重影响临床治疗效果。NorA蛋白介导的药物主动外排成为葡萄球菌对氟喹诺酮类药物耐药的重要机制,利血平等作为NorA外排蛋白抑制剂,可有效降低其耐药性的产生。CCCP等能量抑制剂可加强细菌对氟喹诺酮类药物的摄取量。文章从葡萄球菌对氟喹诺酮类药物耐药机制、耐药抑制剂作用途径和能量抑制剂影响等方面,简要介绍金黄色葡萄球菌氟喹诺酮的耐药抑制剂研究进展。  相似文献   

6.
细菌耐药性的产生机理及其控制对策   总被引:6,自引:2,他引:4  
随着抗菌药的广泛应用,细菌的耐药性越来越高,给临床治疗带来诸多困难,因此了解细菌耐药性的产生机理具有重要意义。抗菌药主要以细菌4个必要的细胞内途径为靶位,包括细胞壁的合成、蛋白质的合成、核酸(DNA或RNA)的合成以及细菌的代谢过程。细菌耐药性产生包括生化机理和基因机理,重要的生化机理包括抗菌药破坏酶的产生、靶位的改变和主动外排系统的出现。细菌耐药性的基因机理主要包括基因的突变和外源抗性基因的获得。近年来,喹诺酮类药物耐药性机理成为了研究的热点,并且已经证明由质粒pMG252介导的耐药性具有重要的意义。  相似文献   

7.
氟喹诺酮类药物的耐药现状及对策   总被引:2,自引:1,他引:1  
氟喹诺酮类药物因其广谱高效、吸收好、体内分布广及耐药性小等特点已成为临床治疗感染性疾病的主要药物之一。但由于盲目及不合理应用,使得其耐药性近年来呈蔓延增长趋势,且耐药机制愈来愈复杂多样。文章就近年氟喹诺酮类药物耐药性的发展及其特点作了综述,并分析了其耐药机制,提出了减缓耐药性的一些相关对策。  相似文献   

8.
近几年合成的第三代喹诺酮类药物抗菌谱广、抗菌活性高,对革兰氏阴性菌有良好的抗菌作用,对细胞、组织穿透性强,易吸收,且在体内分布广泛,对各组织系统的感染均有良好疗效。细菌对其产生突变耐药的发生率低,无质粒介导的耐药性发生,与其他抗菌药无交叉耐药性;大多数品种半衰期相对较长,用药次数少,使用方便。本试验应用氟喹诺酮类药物治疗实验室条件下兔巴氏杆菌攻毒后的家兔和临床患病家兔,比较了它们的效果,取得了一定的数据。  相似文献   

9.
动物用氟喹诺酮类药物的研究   总被引:4,自引:0,他引:4  
氟喹诺酮类药物(FQS)是第3代喹诺酮类药物,是一族化学台成的抗菌药物的总称。自20世纪80年代上市以来.氟喹诺酮类药物因为具有抗菌谱广.抗菌活性强、不易产生耐药性、毒副作用小等特点而成为目前临床上治疗各种感染性疾痫的常用药物。随着氟喹诺酮类药物的不断开发应用.国内外科技工作者对该类药物进行了大量研究工作。  相似文献   

10.
猪链球菌对喹诺酮类药物的耐药性日益严重,尤其在我国更为突出,文章对猪链球菌的耐药性状况、对喹诺酮类药物耐药的分子机制以及如何防止耐药性产生等问题进行了概述,以期为进一步研究提供理论依据.  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
14.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

15.
Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.  相似文献   

16.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

17.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

18.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

19.
The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.  相似文献   

20.
<正>1.INTRODUCTION Ensuring transportation network security is one Of the most daunting challenges confronting homeland security agencies today.Significant research has been dedicated.To model and analyze the vulnerability of transportation systems,while notably fewer studies propose specific strategies for deploying defensive technologies to safeguard these systems.  相似文献   

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