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21.
目的分析贵阳地区儿童重症社区获得性肺炎支气管肺泡灌洗液(BALF)病原学分布及耐药特点。方法收集989例重症社区获得性肺炎患儿临床资料,将支气管肺泡灌液采用支气管镜取出进行细菌培养、病毒以及肺炎支原体(MP)检测。结果(1)989例重症社区获得性肺炎患儿病原检出阳性716例,阳性率72.40%,细菌、病毒、支原体检出率分别33.27% (329例)、22.45%(222例)、31.45%(311例)。(2)细菌感染中的肺炎链球菌、金黄色葡萄球菌为最为常见的革兰阳性菌株(G+);而肺炎克雷伯菌、大肠埃希菌为最为常见的革兰阴性菌株(G-)。培养菌株对青霉素类、红霉素、第1、2、3代头孢类抗生素有较高的耐药性,对头孢吡肟、拉氧头孢、哌拉西林、左氧氟沙星有较高的敏感性,对亚胺培南、万古霉素、利奈唑烷均无耐药发生。(3)病毒感染检出222例,其中呼吸道合胞病毒131例,腺病毒检测49例,流感病毒6例(A型2例,B型4例),副流感病毒36例(1型3例、2型4例、3型29例),病毒检出率以0~12月龄组最高,RSV、ADV感染主要集中在冬春季节。(4)肺炎支原体检出阳性率31.45%(311例),肺炎支原体检出率以3~5岁组最高。结论贵阳地区重症肺炎中肺炎克雷伯杆菌、肺炎链球菌、大肠埃希菌、金黄色葡萄球菌为重要的细菌病原。重要病毒为腺病毒和呼吸道病毒为主,1~12月龄组的病毒感染检出率比较高。 相似文献
22.
新型隐球菌脑膜炎的诊断探讨及文献复习 总被引:3,自引:0,他引:3
目的:探讨新型隐球菌脑膜炎(CNM)的临床特点及诊断方法。方法:对18例CNM患者的临床资料进行回顾性分析并文献复习。结果:18例患者均经病原学确诊。大部分CNM患者为亚急性起病,临床表现无特异性,误诊率高,首诊误诊率为72%,其中误诊为结核性脑膜炎的占69%。结论:脑脊液中找到新型隐球菌是诊断该病的重要依据,多种快速检测手段结合可提高早期诊断率。 相似文献
23.
Carlo Bertucci Enrico Domenici Piero Salvadori 《Journal of pharmaceutical and biomedical analysis》1990,8(8-12):843-846
The application of a circular dichroism (c.d.) detection system in HPLC using a chiral stationary phase is presented. The simultaneous measurement of the absorbance and c.d. signal allows the evaluation of the anisotropy factor (g = Δ/) and thus the determination of the enantiomeric excess (e.e.) of the eluates. When this detection system is used in preparative chiral chromatography the collection of the enantiomeric fractions can be readily optimized. 相似文献
24.
25.
目的:对不同年龄组正常人脑进行水分子扩散加权成像,探讨年龄因素对正常人脑白质及灰质核团ADCav值的影响,为进一步研究放射性脑损伤提供不同年龄段ADCav正常值范围。方法:研究样本60例,分为<60岁和≥60岁两个年龄组,进行脑水分子扩散加权成像,并分别测量额叶和枕叶白质ADC值作为皮质下白质的代表,测量丘脑ADC值作为灰质团块的代表。结果:年龄<60岁组脑白质的ADCav值为(0.70±0.07)×10-3mm2/s,丘脑的ADCav值为(0.83±0.08)×10-3mm2/s;年龄≥60岁组脑白质的ADCav值为(0.73±0.10)×10-3mm2/s,丘脑的ADCav值为(0.84±0.06)×10-3mm2/s。两年龄组脑白质间差异具有统计学意义(P<0.05),丘脑间无统计学意义,白质和丘脑间有显著性差异(P<0.001)。结论:①伴随年龄的增长,正常脑白质ADC值呈现微弱的增长趋势,尤其是60岁以上老年人ADC值的增长趋势更为明显;②定量的ADC值分析对疾病的早期诊断及检测病变的发生、发展都有重要的意义;③临床研究中在对照样本的选取上应注意年龄因素的影响,本研究所得数据可作为进一步研究的正常参考值。 相似文献
26.
N S Davis 《The Prostate》1987,11(4):353-360
The finding of significant numbers of endocrine-paracrine (EP) cells in the prostate glands of guinea pigs and man suggests that these cells may be important in the regulation or modulation of prostatic function. Serotonin is a biogenic amine common to most prostatic EP cells. In order to extend current knowledge relating to these cells, an assay was developed using high-performance liquid chromatography to quantitate serotonin and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) in guinea pig and human prostatic tissue extracts. Levels of serotonin and 5-HIAA in the guinea pig whole-gland preparation were 105.4 +/- 70.6 ng/g and 48.4 +/- 95.7 ng/g, respectively. Normal human prostatic tissue contained 1423.9 +/- 750.8 ng/g serotonin and 66.7 +/- 92.8 ng/g 5-HIAA. Recoveries ranged between 60 and 100%. The detection limits were 24 pg/injection for serotonin and 12 pg/injection for 5-HIAA. This assay provides an expeditious, specific and highly sensitive method for the simultaneous determination of monoamines in guinea pig and human prostatic tissue. 相似文献
27.
Bernhard L mmle Mauro Berrettini Hans Peter Schwarz Mary Jo Heeb John B. Griffin 《Thrombosis research》1986,41(6):747-759
The immunoblotting technique was applied to the study of Factor XII (F.XII) in plasma. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of whole plasma followed by electroblotting of the electropherograms to nitrocellulose (NC) membranes and immunologic detection by a double antibody technique was used. 125-F.XII was transferred to the NC membrane in amounts proportional to the amount applied to the gel provided that a constant amount of carrier protein was present. Based on this, a quantitative assay was developed using either normal plasma or F.XII dilutions in F.XII-deficient plasma as standards. The measurement of F.XII antigen by immunoblotting was reproducible and gave values similar to those obtained by radial immunodiffusion. Two normal plasma pools contained 26 and 29 μ/ml of F.XII according to the immunoblotting assay. Compared to other immunoassays, immunoblotting has the advantage of directly estimating the apparent molecular weight (MW) of the protein of interest. Thus, we could confirm the normal apparent MW (80,000) of a F.XII-like molecule previously isolated from a cross reacting material (CRM)-positive F.XII-deficient plasma. None of eight CRM-negative F.XII-deficient plasmas showed an 80,000 MW immunoreactive molecule. However, five of these eight plasmas had a faint autoradiographic band at 115,000 MW that was similarly seen in only three out of 43 individual normal plasmas. The nature of this 115,000 MW band remains to be defined. 相似文献
28.
计算机辅助检测对检出乳腺X线片中成簇微钙化灶的价值 总被引:4,自引:0,他引:4
目的:探讨计算机辅助检测系统(CAD)对检出乳腺X线钼靶摄影片中成簇微钙化灶的临床应用价值。方法:将22例乳腺X线钼靶片上疑有簇状钙化灶患者和13例正常对照者的140张乳腺钼靶X线片,经专业扫描仪数字化处理后,应用CAD软件标记其中的微钙化灶,由6位放射科医师分别单独阅片,再结合CAD阅片,结果采用受试者操作特性(ROC)曲线法进行分析。结果:6位放射科医师结合CAD阅片后,评价效果均优于未结合CAD时,其中3位低年资医师(有1年临床经验)和1位中年资医师(有5年以上临床经验)的两次评价结果有显著性差异(P<0.05)。结论:CAD有助于提高乳腺X线片中成簇微钙化灶的检出率,尤其对缺少诊断经验医师的作用更大。 相似文献
29.
Dmitri Artemov Zaver M. Bhujwalla Ross J. Maxwell John R. Griffiths Ian R. Judson Martin O. Leach Jerry D. Glickson 《Magnetic resonance in medicine》1995,34(3):338-342
The anticancer agent temozolomide labeled with 13C (8-Carbamoyl-3-13C-methylimidazo-[5,1-d]-1,2,3,5-tetrazin-4-(3H)-one), was noninvasively detected in subcutaneous RIF-1 tumors by a selective cross polarization 13C NMR method, at a field strength of 9.4T. Pharmacokinetics of the drug, at a dose of 150 mg/kg, were determined for intravenous and intraperitoneal modes of administration (three animals per mode). The half-life of the drug in the tumors was approximately 60 min. The uptake and clearance of the drug, however, varied significantly between individual hosts, for both modes of administration. These results demonstrate the feasibility of obtaining pharmacokinetics of anticancer agents for individual tumors without the need for a label that might modify drug activity (e.g., fluorine). The variability of the in vivo measurements, even within the same tumor model, demonstrates the necessity of directly monitoring the tumor to evaluate drug pharmacokinetics. 相似文献
30.
Vasopressin (AVP) receptor binding within hypothalamic sites was compared between cycling and lactating female golden hamsters. The density of AVP receptor binding was analyzed by quantitative autoradiography within the ventrolateral hypothalamus and dorsomedial hypothalamic nucleus. Lactation was correlated with a disappearance of AVP receptor binding within the ventrolateral hypothalamus. In contrast, lactation was associated with a two- to three-fold increase in the density of AVP receptor binding within the dorsomedial hypothalamic nucleus. These results suggest that AVP receptor binding within the ventrolateral hypothalamus is responsive to gonadal hormones in female golden hamsters. However, the increase in binding observed within the dorsomedial hypothalamus may be related to other neurobiological changes associated with lactation. 相似文献