首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
目的调查广州地区老年患者肺炎链球菌分离株对青霉素的敏感性,并分析其亲缘关系。方法K—B纸片法对33株分离自老年住院病人的肺炎链球菌进行青霉素药敏试验;应用PCR技术检测青霉素结合蛋白基因pbp1a,pbp2x,pbp2b;用盒式PCR(BOX—PCR)分析菌株间亲缘关系。用多位点测序分型技术(multilocus sequence typing,MLST)检测青霉素耐药菌株的分子分型。结果青霉素的耐药率为3.03%(1/33):用PCR方法鉴定PSSP的准确率为68.75%;BOX-PCR可将这33株肺炎链球菌分为21型。MIST分型显示,青霉素耐药菌株属ST271型。结论广州地区老年患者肺炎链球菌对青霉素耐药率较低.用PCR方法检测PSSP有一定的可行性。BOX—PCR显示了较高的分辨率,能快速可靠地检测菌株间的亲缘关系。广州地区流行的耐药克隆与Taiwan^19F-14株同源。  相似文献   

2.
肺炎链球菌的耐药性和pbp2b基因扩增产物图谱的相关性   总被引:13,自引:1,他引:13  
目的 了解肺炎链球菌对青霉素和其它抗生素的耐药情况;对40株青霉素敏感菌株和30株青霉素不敏感菌株进行pbp2b基因扩增产物RFLP图谱相关性研究。方法 采用肉汤稀释法、E-试验和K-B纸片法进行抗生素药物敏感试验;通过用特异性引物pF和pR对肺炎链球菌进行PCR扩增,并对扩增产物进行限制性内切酶HaeⅢ消化反应。结果 肺炎链球菌对青霉素的不敏感率为9.9%~14.6%;40株青霉素敏感菌株(MICs≤0.094μg/ml)中的39株(97.5%)为s1、s2和s3三种之一,1株为r1;30株青霉素不敏感菌株(MICs≥0.12μg/ml)中的26株(86.7%)为r1-16六种之一,其余4株为s1。结论 青霉素和β-内酰胺酶类抗生素对北京地区的肺炎链球菌具有活性;肺炎链球菌的耐药性和pbp2b基因扩增产物图谱之间有相关性。  相似文献   

3.
肺炎链球菌pbp2B基因突变与耐药表型关系的研究   总被引:1,自引:0,他引:1  
肺炎链球菌主要通过青霉素结合蛋白基因突变,从而改变细胞壁上高相对分子质量青霉素结合蛋白(PBP)的结构,降低了其对抗生素分子的亲和性而产生对青霉素等B内酰胺类抗生素的耐药性。我们对分离自本院的30株肺炎链球菌(青霉素敏感4株,中介5株,耐药21株)用聚合酶链反应(PCR)扩增p6p2B基因,对PCR产物直接进行DNA测序,并与青霉素敏感的SpR6株序列(GenBank登录号NC003098)相比较。  相似文献   

4.
目的调查急慢性上颌窦炎及咽炎患者肺炎链球菌带菌及耐药情况. 方法用E-test法及纸片扩散法测定耐药情况. 结果 86株肺炎链球菌中,对青霉素敏感64株(74.4%),低度耐药18株(20.9%),高度耐药4株(4.7%),青霉素耐药菌株对红霉素、氯霉素、复方新诺明及四环素的耐药率比青霉素敏感株高,所有菌株对万古霉素敏感. 结论了解细菌耐药性的变化是合理应用抗生素的重要依据.  相似文献   

5.
目的 调查研究肺炎链球菌临床分离株的pbp2x基因和氨基酸序列的变异特点,探讨本地区的肺炎链球菌对青霉素及头孢噻肟的耐药机制.方法 2006年1月-2007年2月收集肺炎链球菌临床分离株34株,进行青霉素及头孢噻肟药敏试验,对青霉素不敏感的肺炎链球菌(PNSP)的青霉素结合蛋白pbp2x基因进行PCR扩增和测序,并进行BLAST分析.结果 有12株PNSP(青霉素及头孢噻肟MIC≥0.5 mg/L)发生了2个重要位点的氨基酸的替换:第一个保守基序STMK内Thr338→Ala及第三个保守基序KSG之前的Leu546→Val氨基酸替换.另外,菌株15发生了第二个保守基序SSN之前的His394→Leu氨基酸替换,而且本研究首次发现了紧邻第一个保守基序STMK后,Met342→Ile位点的氨基酸替换.有17个菌株的pbp2x基因的核苷酸及氨基酸序列出现了新的变异,已向GenBank提交,获得序列号:EU044831、EU089706-EU089709、EU106881-EU106884、EU124672.结论 本地区大多数PNSP的pbp2x核苷酸及氨基酸变异序列高度相似,提示肺炎链球菌对青霉素及头孢噻肟的耐药与pbp2x基因变异相关.  相似文献   

6.
目的 调查急慢性上颌窦炎及咽炎患者肺炎链球菌带菌及耐药情况。方法 用E—test法及纸片扩散法测定耐药情况.结果 86株肺炎链球菌中,对青霉素敏感64株(74.4%),低度耐药18株(20.9%),高度耐药4株(4.7%),青霉素耐药菌株对红霉索、氯霉素、复方新诺明及四环素的耐药率比青霉素敏感株高,所有菌株对万古霉素敏感.结论 了解细菌耐药性的变化是合理应用抗生素的重要依据。  相似文献   

7.
目的 研究肺炎链球菌murM基因变异与青霉素及头孢曲松耐药的相关性。方法 应用PCR技术扩增肺炎链球菌murM基因并进行基因测序。选取肺炎链球菌株 5 5株 ,包括青霉素敏感株 10株 (MIC≤ 0 .0 6 μg/ml) ;青霉素耐药株 4 5株 ,其中低水平耐药 10株 (MIC 0 .12~ 1μg /ml) ,高水平耐药 35株 (MIC≥ 2 μg/ml) ,在青霉素高水平耐药菌株中 ,对头孢曲松耐药 13株 (MIC≥ 2 μg/ml)。用敏感株R36AmurM基因序列作为比较标准。结果  5 5株肺炎链球菌murM基因PCR产物测序结果 ,16株murM基因发生显著变异 (变异率≥ 3% ) ,1株青霉素MIC 3μg/ml、头孢曲松MIC 2 μg/ml的菌株 ,其murM基因变异率 3.4 % ;15株青霉素MIC≥ 8μg/ml或头孢曲松MIC≥ 2 μg/ml的菌株 ,murM基因变异率达 10 % ,呈嵌合式变异。murM基因变异与肺炎链球菌青霉素及头孢曲松MIC显著相关 (χ2 =36 .5 32 ,P <0 .0 1;χ2 =37.116 ,P <0 .0 1)。结论 肺炎链球菌murM基因变异与青霉素高度耐药 (MIC≥8μg/ml)及头孢曲松耐药 (MIC≥ 2 μg/ml)有显著的相关性。  相似文献   

8.
目的了解广州地区肺炎住院的患儿感染肺炎链球菌的耐药性及血清型分布情况。方法用吸痰法采集患儿痰标本进行涂片,革兰氏染色镜检,合格痰标本划线接种血平板,用E-test法检测分离到的肺炎链球菌对青霉素、阿莫西林、头孢曲松、头孢呋辛、亚胺培南、氧氟沙星、万古霉素、红霉素和克林霉素9种药物的耐药性,采用K-B法检测四环素、复方新诺明的耐药性,并采用荚膜肿胀技术对分离到的79株肺炎链球菌进行血清分型。结果79株肺炎链球菌中青霉素耐药肺炎链球菌(PRSP)11.4%,青霉素中介肺炎链球菌(PISP)77.2%,青霉素敏感肺炎链球菌(PSSP)11.4%,对红霉素、克林霉素的耐药率分别为100%和93.7%,对阿莫西林、氧氟沙星、万古霉素的耐药率均为0,对头孢曲松、头孢呋辛、亚胺培南的耐药率分别为3.8%、72.2%、2.5%。79株肺炎链球菌中只有1株PSSP仅对红霉素耐药.78株肺炎链球菌对两种以上药物耐药.多重耐药率为98.7%(78/79),同时对克林霉素、红霉素、四环素、复方新诺明耐药的菌株65株,占82.3%(65/79)。79株肺炎链球菌血清型分别为19F(70.9%),23F(16.5%),6B(5.1%),4(2.5%),15B(2.5%),不能分型(2.5%),7价疫苗涵盖率为94.9%(75/79)。结论广州地区肺炎住院患儿肺炎链球菌对大环内脂类抗生素红霉素和林可酰胺类抗生素克林霉素耐药情况严重,对二代头孢菌素头孢呋辛耐药率居高,临床治疗儿童肺炎链球菌感染的肺炎应首选阿莫西林和三代头孢菌素。7价疫苗覆盖率高。预防儿童肺炎链球菌感染所致的肺炎,采用7价疫苗可以达到很好效果。  相似文献   

9.
对1966年~1993年21个省分离的218株A、B和C群脑膜炎奈瑟氏菌(Nm)检查对青霉素的耐药情况及其机理,耐药菌株和敏感菌株的penA基因扩增后经HpaⅡ消化并比较了它们的酶切图谱。108株A群Nm中有2株耐药,它们是1987年和1988年分离的;101株B群Nm中有6株耐药,1983年以前仅1株,其余5株是以后的,耐药菌株从3.8%上升到6.7%;9株C群Nm中分离出1株耐药菌株,为70年代分离的。上述耐药菌株中,1株A群和5株B群为病人菌株,其余皆为携带者菌株。耐药的A群和C群Nm与其敏感菌株penA基因的HpaⅡ酶切图谱相同,但耐药的B群Nm的penA基因酶切图谱显出5种谱型,它们与敏感菌株的图谱明显不同。实验结果初步表明我国所分离的少数Nm对青霉素耐药,B群Nm较A群耐药明显些,前者对青霉素耐药可能是penA基因的改变所致,关于A群和C群Nm对青霉素的耐药机理尚需进一步探讨。  相似文献   

10.
79株肺炎链球菌的耐药性测定   总被引:38,自引:0,他引:38  
目的调查北京地区肺炎链球菌对青霉素等抗生素的耐药率。方法用Etest及琼脂稀释法测定临床分离的79株肺炎链球菌15种抗生素的最低抑制浓度(MIC)。结果Etest测得10株(12.7%)低耐青霉素(MIC0.125~1μg/ml),1株(1.3%)高耐青霉素(MIC4μg/ml);仅1株处于头孢曲松、头孢噻肟中介范围(MIC1μg/ml).琼脂稀释法测得阿莫西林、阿莫西林/棒酸、头孢呋肟、环丙沙星、氯霉素、四环素、红霉素的耐药率分别为1.3%、1.3%、2.5%、2.5%、16.5%、49.4%、40.5%,所有菌株对头孢曲松、万古霉素敏感。结论北京地区14%的肺炎链球菌耐青霉素,耐三代头孢菌素及多重耐药株罕见。  相似文献   

11.
Renal dysplasia and asplenia in two sibs   总被引:2,自引:0,他引:2  
A family is reported in which two sibs, one male and the other female, both died within 24 hours of birth with enlarged polycystic kidneys. Postmortem histology in the second child showed gross renal dysplasia. In both children the pancreas was enlarged, nodular and cystic but the liver appeared macroscopically normal. In the second child, histological examination confirmed pancreatic fibrosis with cystic dilation of ducts, but showed portal fibrosis with bile duct proliferation in the liver.
This combination of findings is very reminiscent of those in a girl and her brother reported by Ivemark et al. (1959). The children reported here also showed absence or hypoplasia of the spleen, cardiac anomalies and other features of the Ivemark syndrome (Ivemark 1955), a quite different, usually sporadic, congenital disorder. It is suggested that the children described here have a distinct lethal congenital disorder, probably inherited in an autosomal recessive manner.  相似文献   

12.
Over 200 schizophrenic patients belonging to three major and interrelated pedigree complexes have been investigated over the past 30 years in a North Swedish geographically isolated population, presently numbering about 6,000. An intensive investigation of a number of biochemical correlates and genetic markers in a few selected families belonging to one of the major pedigrees has indicated new strategies for the current research program.
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc2 (group specific antigen). Both enzymes are subject to genetic variation. A positive score for linkage between schizophrenia and low plasma DBH activity has been calculated, but, so far, available data are insufficient for discrimination between linkage and partial contribution of genetically controlled low plasma DBH to the pathogenesis of the disease. Alternatively, both mechanisms could be involved.
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population.  相似文献   

13.
About 1900, modern food selection and processing caused widespread epidemics of the B vitamin deficiency diseases of beriberi and pellagra which, for genetic reasons, often expressed as different diseases ranging from bowel and heart disease to dermatoses and psychoses. But the B vitamins merely help convert essential fatty acids (EFA) into the prostaglandin (PG) tissue regulators and it now turns out that, through hydrogenation, milling and selection of w3-poor southern foods, we have also been systematically depleting, by as much as 90%, a newly discovered trace Nordic EFA (w3) of special importance to primates and sole precursor of the PG3(4) series, even as a concurrent fiber deficiency increases body demand for EFA. Since substrate EFA is processed by many B vitamin catalysts, an EFA deficiency will mimic a panhypovitaminosis B, i.e., a mixture of substrate beriberi and substrate pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse endemic disease. This would consitute a second stage of the Modern Malnutrition and explain why some workers now hold the dominant diseases of modermized societies to be new, nutritionally based, pellagraform yet lipid-related and to range, once again, from heart disease to psychosis. It is an assumption that our dominant diseases are unrelated to each other or are merely revealed by our diagnostic acumen and therapeutic success; and that hydrogenating millions of tons of food oils annually, to destroy the rancidity producing w3-EFA, is safe for primates. Extensive beriberiform disease is reported here in 32 typical cases taken from medical practice which responds strikingly to linseed oil supplements (60% w3-EFA) in confirmation of identical results in Capuchins.  相似文献   

14.
There are an estimated over 200 million yearly cases of malaria worldwide. Despite concerted international effort to combat the disease, it still causes approximately half a million deaths every year, the majority of which are young children with Plasmodium falciparum infection in sub-Saharan Africa. Successes are largely attributed to malaria prevention strategies, such as insecticide-treated mosquito nets and indoor spraying, as well as improved access to existing treatments. One important hurdle to new approaches for the treatment and prevention of malaria is our limited understanding of the biology of Plasmodium infection and its complex interaction with the immune system of its human host. Therefore, the elimination of malaria in Africa not only relies on existing tools to reduce malaria burden, but also requires fundamental research to develop innovative approaches. Here, we summarize our discoveries from investigations of ethnic groups of West Africa who have different susceptibility to malaria.  相似文献   

15.
16.
Newton H 《Medical history》2011,55(2):153-182
Sick children were ubiquitous in early modern England, and yet they have received very little attention from historians. Taking the elusive perspective of the child, this article explores the physical, emotional, and spiritual experience of illness in England between approximately 1580 and 1720. What was it like being ill and suffering pain? How did the young respond emotionally to the anticipation of death? It is argued that children’s experiences were characterised by profound ambivalence: illness could be terrifying and distressing, but also a source of emotional and spiritual fulfilment and joy. This interpretation challenges the common assumption amongst medical historians that the experiences of early modern patients were utterly miserable. It also sheds light on children’s emotional feelings for their parents, a subject often overlooked in the historiography of childhood. The primary sources used in this article include diaries, autobiographies, letters, the biographies of pious children, printed possession cases, doctors’ casebooks, and theological treatises concerning the afterlife.  相似文献   

17.
Recent advancements in agricultural biotechnology have created a need for analytical techniques to determine introduced proteins in crops enhanced through modern biotechnology techniques. These proteins are expressed in plant tissues and may be present in food ingredients. Immunoassays are ideally suited for protein detection and may be used as both quantitative and threshold methods. Microplate ELISA and lateral flow devices are two of the most commonly used immunoassay formats for agricultural biotechnology applications. This paper provides general background information and a discussion of criteria for the validation and application of immunochemical methods to the analysis of proteins introduced into plants and food ingredients using biotechnology methods. It is the result of a collaborative effort of members of the Analytical Environmental Immunochemical Consortium. This collaborative effort represents the combined expertise of several organizations to reach consensus on establishing guidelines for the validation and use of immunoassays. Further, the paper offers developers and users a consistent approach to adopting the technology as well as aid in producing accurate and meaningful results.  相似文献   

18.
HLA-A,-B,-C,-DRB1 and -DQB1 alleles have been studied in Chimila Amerindians from Sabana de San Angel (North Colombian Coast) by using high resolution molecular typing. A frequent extended haplotype was found:HLA-A*24:02-B*51:10-C*15:02-BRB1*04:07-DQB1*03:02 (28.7%) which has also been described in Amerinndian Mayos Mexican population (Mexico, California Gulf, Pacific Ocean). Other haplotypes had already been found in Amerindians from Mexico (Pacific and Atlantic Coast), Peru (highlands and Amazon Basin), Bolivia and North USA. A geographic pattern according to HLA allele or haplotype frequencies is lacking in Amerindians, as already known. Also, five new extended haplotypes were found in Chimila Amerindians. Their HLA-A*24:02 high frequencies characteristic is shared with aboriginal populations of Taiwan; also, HLA-C*01:02 high frequencies are found in New Zealand Maoris, New Caledonians and Kimberly Aborigines from Australia. Finally, this study may show a model of evolutionary factors acting and rising one HLA allele frequency (-A*24:02), but not in others that belong to the same or different HLA loci.  相似文献   

19.
The preparation steps usually necessary for obtaining ultrathin frozen sections of biological material (chemical prefixation, enclosing, cryoprotective treatment, freezing, sectioning, and post-staining the sections for transmission electron microscopy) are submitted to a critical analysis. The application of cryo-ultramicrotomy, in particularly for cytochemical purposes, is reviewed. Fundamental considerations of chemical prefixation and poststaining are supported by examples from yeast cytology. Furthermore, the efficiency of the cryo-ultramicrotomy (electron optical resolution of ultrastructural details) is demonstrated on yeast cells and protoplasts.  相似文献   

20.
Starting with the integument, we see many organs are contractile sacs or multiples thereof, which tubes or bags constitute the major part of the entire body. Recognition of this basic unit and its characteristics sheds new light, individually and collectively, on many disorders previously considered unrelated. Muscular tears and perforations develop in the walls of these chambers, being no way peculiar to those organs, wherein, hydrochloric acid occurs. So, it is not necessary to explain the absence of excessive acid from patients who exhibit holes in the gastric, uterine, aortic, duodenal, rectal, pulmonary, retina, and other walls. Muscle, not acid is the great common factor relating idiopathic disorders in the gastrointestinal tract to each other and to similar diseases in other systems. When the units are linked together, the lesions tend to appear as arthropathies, i.e. at the joints. Rephrasing common-place observations, frees us from conventional, conceptual cul-de-sacs. An observation is only as good as its interpretation, so all possibilities must be considered, otherwise, we will remain blinded by our misconceptions.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号