产超广谱β-内酰胺酶及AmpC酶的阴沟肠杆菌的耐药性分析

目的 分析产超广谱β-内酰胺酶（extended spectrum β lactamases,ESBLs）及AmpC酶的阴沟肠杆菌的分布情况及耐药特征.方法 选择49株阴沟肠杆菌,采用纸片扩散法进行药物敏感试验,按美国临床实验室标准化协会推荐的确证试验检测产ESBLs阳性菌株;头孢西丁纸片扩散法初步筛选产AmpC酶阳性菌株,采用PCR检测AmpC酶基因.结果 抗生素敏感试验结果显示阴沟肠杆菌对头孢西丁、替卡西林/克拉维酸、头孢曲松、氨曲南的耐药率均达79.6％以上,对美罗培南敏感率较高,达91.8％.49株阴沟肠杆菌中对头孢西丁耐药的菌株46株（93.9％）;产ESBLs菌株29株（59.2％）,PCR 扩增产AmpC酶的阴沟肠杆菌36株（73.5％）,同时产两种酶的菌株为13株（26.5％）.结论 产ESBLs 及AmpC酶阴沟肠杆菌普遍且耐药现象严重.     

介绍一种同时存在AmpC酶和超广谱β内酰胺酶的检测方法

目的：研究自血培养分离的阴沟肠杆菌的耐药特点，以指导临床用药。方法：收集1997-2000年期间我院住院患血液中分离到的10株阴沟肠杆菌，用纸片扩散法对13种抗菌药物进行了检测，用改良的酶提取物三维试验方法进行持续高产AmpC酶和超广谱β内酰胺酶（ESBLs）的双重检测。结果：10株阴沟肠杆菌中1株持续高产AmpC酶，1株既有持续主产AmpC酶，又产ESBLs；3株只产ESBLs，其余5株未发现持续高产AmpC酶和ESBLs。2株持续高产AmpC酶和3株产ESBLs均对第三代头孢菌素和β内酰胺酶抑制剂的复方制剂等多种抗菌药显示高度耐药。结论：使用改良的酶提取物三维试验可同时检测高产AmpC酶（包括染色体型和质粒型）和ESBLs的菌株。根据阴沟杆菌产生不同的β内酰胺酶选择性用药，治疗高产AmpC酶多耐药菌，使用第三代头孢菌素和酶抑制复方制剂通常导致临床治疗失败，应选用第四代头孢菌素或碳青霉烯类，或两与氨基糖苷类或氟喹诺酮类联合治疗。碳青霉烯类抗生素是惟一对AmpC酶和ESBLs均稳定的β内酰胺类抗生素，可用于治疗产ESBLs菌引起的重症感染。     

非特异性阴道炎患者分泌物肠杆菌产β-内酰胺酶研究

目的：分析非特异性阴道炎患者分泌物的肠杆菌中产β-内酰胺酶情况,为临床合理使用抗菌药物提供依据。方法应用三维抑制试验回顾性分析2012～2013年625例确诊为非特异性阴道炎患者送检的分泌物经中的肠杆菌产头孢菌素酶（AmpC）、超广谱β-内酰胺酶（ESBLs）、和超超广谱β-内酰胺酶（SSBL）的情况。结果各种肠杆菌β-内酰胺酶表型中,大肠埃希菌、阴沟肠杆菌、产气肠杆菌产 ESBLs≥25％属于高产类型;阴沟肠杆菌产AmpC≥25％属于高产酶类型,且所有菌株产β-内酰胺酶均大于或等于10％,提示在非特异性阴道炎患者体内肠杆菌β-内酰胺酶表型比例较高。结论针对非特异性阴道炎患者合理使用β-内酰胺类抗菌药物避免耐药株产生显得非常重要。     

PER-1型超广谱β内酰胺酶在革兰阴性杆菌中的流行情况调查

目的；了解：PER-1型超广谱β内酰胺酶(ESBLs)在革兰阴性杆菌中的流行情况。方法：采用纸片扩散试验初筛和确证ESBLs表型，用聚合酶链反应(PCR)扩增耐药基因及PCR产物测序验证PER-1型ESBLs结果：ESBLs的总检出率27．3％(179／656)，PER-1型占ESBLs的8．9％(16／179)，产酶菌以鲍曼不动杆菌为主。结论：应加强对：PER-1型ESBLs的检测，以有效控制由产生该型ESBLs细菌引起的医院感染。     

改良三维试验同时检测阴沟肠杆菌中的AmpC酶和超广谱β-内酰胺酶

目的研究瑞安市人民医院临床标本分离出的的阴沟肠杆菌产AmpC酶和超广谱β-内酰胺酶（ESBLs）情况，以指导临床用药。方法收集瑞安市人民医院2006年1～12月临床标本分离到的96株阴沟肠杆菌，用纸片扩散法对14种抗菌药物进行了药敏试验，用改良三维试验进行持续高产AmpC酶和ESBLs的双重检测。结果96株阴沟肠杆菌中11株（11．5％）高产AmpC酶；2株（2．1％）既持续高产AmpC酶又产ESBLs；40株（41．6％）只产ESBLs；其余43株（44．8％）未发现持续高产AmpC酶或ESBLs。结论使用改良的酶提取物三维试验可同时检测高产AmpC酶和ESBLs菌株，应根据阴沟肠杆菌产生不同的ESBLs来选择性用药。     

阴沟肠杆菌高产AmpC酶和ESBLs的检测及其多重耐药机制的研究

目的探讨深圳地区多重耐药阴沟肠杆菌的流行状况及耐药机制。方法研究者对临床分离82株阴沟肠杆菌采用超广谱β-内酰胺酶(ESBLs)表型确证试验和氟氯西林(FCC)双抑制剂扩散协同试验法(DIDST)分别检测ESBLs、持续高产AmpC酶。结果从82株临床分离的阴沟肠杆菌中,检出33株(占40.2%)产去阻遏持续高产AmpC酶,25株(占30.5%)产ESBLs,14株(占17.1%)同时表达AmpC酶和ESBLs,10株(占12.2%)两种酶都不表达。结论高产AmpC酶和ESBLs是阴沟肠杆菌对头孢菌素耐药的主要机制,高产AmpC酶和ESBLs的产生与β酰胺类抗菌药物的广泛应用有着直接关系,临床治疗多重耐药阴沟肠杆菌应首选碳青霉烯类药物。     

我院2009年度大肠埃希菌耐药情况的调查

目的了解我院大肠埃希菌对各种抗菌药物耐药情况,初步探讨其耐药机制。方法通过收集我院2009年度各种标本中检出的大肠埃希菌,通过纸片扩散法检测抗菌药物敏感性和两纸片协同法及CLSI纸片确证试验来筛选和确证耐药机制。结果各类标本中共检出大肠埃希菌80例,其中产超广谱β内酰胺酶(ESBLs)41例,产质粒型头孢菌素酶(AmpC酶)2例。结论 我院作为基层医院,但大肠埃希菌耐药率不低,产超广谱β内酰胺酶的大肠埃希菌比率较高。     

某地区分离自呼吸系统感染患者产ESBLs、AmpC酶肠杆菌科细菌耐药性检测

目的 分析肠杆菌科细菌临床分离株产超广谱β-内酰胺酶(ESBLs)和头孢菌素酶(AmpC酶)情况,及其与肠杆菌科细菌耐药性的关系.方法 收集该地区12家医院2009～2010年分离自呼吸系统感染患者呼吸道标本的肠杆菌科细菌1 612株,双纸片增效法检测ESBLs、三维试验检测AmpC酶、K-B纸片法检测菌株耐药性,采用χ2检验进行统计学分析.结果 1 612株细菌中,产ESBLs和AmpC酶菌株检出率分别为45.0%(726/1 612)和11.6%(187/1 612),产酶株对多种抗菌药物的耐药率高于非产酶株;未检出碳青霉烯类抗菌药物耐药菌株.结论 分离自该地区呼吸道感染患者呼吸道标本的产ESBLs和AmpC酶肠杆菌科细菌具有多药耐药性,应加强细菌耐药性监测,采取有效措施防止耐药性的水平传播.     

165株肠杆菌科细菌产超广谱β-内酰胺酶和AmpC酶状况及耐药性分析

目的了解江都地区肠杆菌科细菌产β-内酰胺酶的类型及耐药状况,并比较不同产酶茵对常规抗菌药物的耐药率。方法利用琼脂纸片扩散（K—B）法按美国国家临床实验室标准委员会（CLSI）规定检测超广谱β-内酰胺酶（ESBLs）,用头孢西丁敏感试验筛查AmpC酶并做三维确证试验。结果在165株肠杆菌科细菌中,41株产ESBLs（24．9％）,22株产AmpC酶（13．3％）,8株同时产ESBLs和AmpC酶（4．9％）。不同产酶菌对13种抗菌药物耐药率明显不同,亚胺培南耐药率最低,哌拉西林／他唑巴坦、头孢吡肟次之。结论治疗产ESBLs和（或）AmpC酶的肠杆菌科细菌感染,亚胺培南等碳青霉烯类药物为首选,哌拉西林／他唑巴坦、头孢吡肟、头孢哌酮／舒巴坦及阿米卡星为备选药物。     

阴沟肠杆菌6株中产超广谱β内酰胺酶的基因型

目的：研究阴沟肠杆菌6株的超广谱β内酰胺酶(ESBLs)的基因型。方法：分别使用对TEM型、SHV型和CTX-M型基因特异的引物,PCR扩增6株阴沟肠杆菌接合子Esbl基因,对PCR产物直接测序分析其基因型。结果：3株阴沟肠杆菌的接合子均含有CTX—M-3型酶,同时含有TEM型酶。另3株阴沟肠杆菌接合子均含有一种等电点为8．3未知的β内酰胺酶,同时含有一种pI为5．4或5．5未知的β内酰胺酶。结论：临床分离的阴沟肠杆菌可产CTX-M-3型酶,对头孢菌素类产生耐药性。     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.     

Dissociable correlates of two classes of retrieval processing in prefrontal cortex

Although substantial evidence suggests that the prefrontal cortex (PFC) implements processes that are critical for accurate episodic memory judgments, the specific roles of different PFC subregions remain unclear. Here, we used event-related functional magnetic resonance imaging to distinguish between prefrontal activity related to operations that (1) influence processing of retrieval cues based on current task demands, or (2) are involved in monitoring the outputs of retrieval. Fourteen participants studied auditory words spoken by a male or female speaker and completed memory tests in which the stimuli were unstudied foil words and studied words spoken by either the same speaker at study, or the alternate speaker. On "general" test trials, participants were to determine whether each word was studied, regardless of the voice of the speaker, whereas on "specific" test trials, participants were to additionally distinguish between studied words that were spoken in the same voice or a different voice at study. Thus, on specific test trials, participants were explicitly required to attend to voice information in order to evaluate each test item. Anterior (right BA 10), dorsolateral prefrontal (right BA 46), and inferior frontal (bilateral BA 47/12) regions were more active during specific than during general trials. Activation in anterior and dorsolateral PFC was enhanced during specific test trials even in response to unstudied items, suggesting that activation in these regions was related to the differential processing of retrieval cues in the two tasks. In contrast, differences between specific and general test trials in inferior frontal regions (bilateral BA 47/12) were seen only for studied items, suggesting a role for these regions in post-retrieval monitoring processes. Results from this study are consistent with the idea that different PFC subregions implement distinct, but complementary processes that collectively support accurate episodic memory judgments.     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高＜20％视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P＜0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P＜0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P＜0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.     

Digital imaging among medical facilities

The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.     

Myocardial elastography at both high temporal and spatial resolution for the detection of infarcts

Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.     

Clinical Pharmacokinetics of Morphine

Morphine, the most widely used mu-opioid analgesic for acute and chronic pain, is the standard against which new analgesics are measured. A thorough understanding of the pharmacokinetics of morphine is required in order to safely and effectively use this analgesic in a wide variety of patients with different levels of organ function. A MEDLINE search was conducted to identify literature published between 1966 and January 2002 relevant to the pharmacokinetics of morphine. These publications were reviewed and the literature summarized regarding unique and clinically important elements of morphine disposition relative to its parenteral administration (including intravenous, intramuscular, subcutaneous, epidural and intrathecal administration), absorption profile (immediate release, controlled release, and sublingual/buccal, and rectal administration), distribution, and its metabolism/ excretion. Special populations, including infants, elderly, and those with renal/liver failure, have a unique morphine pharmacokinetic profile that must be taken into account in order to maximize analgesic efficacy and reduce the risk of adverse events.