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101.
A limited flip angle gradient-echo 3D volume acquisition imaging protocol for mapping partial pressure of oxygen (pO2) in perfluorocarbon compounds (PFCs) at low field (0.14 T) is presented. The pO2 measurement method is based on the paramagnetic effect of dissolved molecular oxygen (O2) which reduces the PFC 19F T1? Specific objectives related to imaging of PFCs through use of the protocol include improved image signal-to-noise characteristics and elimination of 19F chemical shift artifacts. A parametric Wiener deconvolution filtering algorithm is used for suppression of 19F chemical shift artifacts. Application of the protocol is illustrated in a series of calculated pO2 maps of a gas equilibrated, multi-chamber phantom containing perfluorotributylamine (FC-43). The utility of the protocol is demonstrated in vivo through images of a commercially available perfluorocarbon based blood substitute emulsion containing FC-43 sequestered in the liver and spleen of a rat.  相似文献   
102.
Assessment of carbohydrate tolerance in pregnancy   总被引:4,自引:0,他引:4  
A review is given of the various methods of assessing carbohydrate tolerance in pregnancy. Oral glucose tolerance screening and diagnostic tests have been in use for more than 25 years. They are easily administered, relatively inexpensive, and present reasonable sensitivity; therefore, they continue to be used quite extensively. However, lack of reproducibility of the results and side effects such as nausea, vomiting, and headache have led to the use of alternate methods including glucose polymer (Polycose) and standard breakfast meals. These methods have been reported to present satisfactory results in clinical practice. Glycosylated hemoglobin (HbA1c) and fructosamine assays are also alternate forms of testing carbohydrate metabolism HbA1c measurement have been proven insensitive as a screening test for gestational diabetes, while their use as an index of overall glucose control remains valuable. The role of fructosamine in the assessment of carbohydrate intolerance remains controversial with conflicting claims made by various investigators regarding its sensitivity in detecting gestational diabetes and its response to alterations in glycemic control. In this review, the relative advantages and disadvantages of each glucose tolerance test are discussed and recommendations are given regarding their utility in pregnancy.  相似文献   
103.
隐睾患儿血清FSH、LH、T水平及其临床意义   总被引:2,自引:0,他引:2  
目的研究隐睾患儿血中促卵泡激素(FSH)、促黄体激素(LID和睾酮(T)激素水平变化,探讨其临床意义及在隐睾症发病中的作用。方法应用化学发光免疫技术检测42例隐睾症和23例斜疝(对照组)患儿血清FSH、LH、T水平。结果单侧隐睾症组和斜疝组之间血清FSH、LH和T水平无显著性差异(P>0.05);(2)双侧隐睾组血清FSH水平高于斜疝组,差别有统计学意义(P<0.05);单侧隐睾症组血清FSH高于斜疝组,低于双侧隐睾症组,差别无统计学意义(P>0.05)。结论(1)血清中性激素LH和T水平的变化在隐睾发生中并不起主要作用;(2)血清FSH水平的升高可能反映睾丸功能损害严重程度。  相似文献   
104.
目的了解流行性出血热病毒(EHFV)对心脏的损害情况。方法对103例流行性出血热(EHF)患者的心电图及心肌酶学检测结果进行分析。结果72例(69.9%)患者出现心电图异常,以窦性心动过缓(27.9%)及窦性心动过速(22.3%)最常见,明显高于其它类型的心电图改变(P分别<0.05和0.001)。103例流行性出血热(EHF)患者的CK、LDH及HBDH的升高者分别为43例(41.2%)、73例(70.9%)及46例(44.7%),以LDH异常最常见。轻型、中型、重型及危重型流行性出血热患者的LDH值分别为(346.3±155.6)IU/L、(330.7±130.7)IU/L、(1114.4±872.4)IU/L及(1227.1±936.7)IU/L,经统计学处理重型及危重型的值与轻型、中型比较均有显著性或高度显者性差异。结论EHF患者并发心肌损害较普遍,而且病情愈重者,心肌损害愈严重。  相似文献   
105.
关于课堂多媒体教学的思考   总被引:10,自引:1,他引:9  
多媒体教学已成为课堂教学的一种常用手段,多媒体教学应从实际需要出发,以提高教学效果为目标;需要教师掌握多种计算机及多媒体知识技能,科学地进行教学设计;教学过程中应发挥多媒体的优势,注重师生交流。对此本文进行了探讨。  相似文献   
106.
OBJECTIVE: To study the effect of the cervical plexus and the accessory nerve to the function of the trapezius muscle. STUDY DESIGN AND SETTING: Eighteen adult male Sprague-Dawley rats were randomly divided into three groups. The neurotomies were performed in the left sides and the right sides served as within-subject controls. In group A, the accessory nerve was transected. The C2-5 were transected in group B, and both of the accessory nerve and C2-5 were cut in group C. The electrophysiologic, myophysiologic, and histologic changes of the muscles were measured. RESULTS: There were significant differences (P < 0.05) between the three groups in the recovery rates of the transverse area of the muscles. The CMAP recorded from the experimental sides in group B were similar to the control sides. The values of the maximum tension of the tetanus contraction between the two sides showed no differences either (P > 0.05). CONCLUSION: The accessory nerve supplies the most important motor input to the trapezius. Motor innervations of the cervical plexus are not very significant.  相似文献   
107.
广西巴马长寿乡壮族长寿老人永生细胞库的建立   总被引:3,自引:0,他引:3  
目的:建立广西巴马长寿乡壮族长寿老人永生细胞库。方法:使用EB病毒转化外周血B淋巴细胞方法。结果:建立了长寿者外周血细胞转化永生细胞株的方法,转化成功率77.4%。建立了65株长寿老人、直系亲属永生细胞株及长寿老人资料库和完整的细胞株档案。结论:广西巴马长寿乡壮族长寿老人永生细胞库的建立为永久保存细胞系及后续研究提供了必要的基础。  相似文献   
108.
OBJECTIVE: To study how blood supply of the esophageal and gastric stumps influences the anastomotic healing after esophagogastrostomy in rabbits. METHODS: Twenty-seven New Zealand rabbits were randomly divided into 3 groups to receive esophagogastrostomy, followed by different procedures. Except for those in group I, all the rabbits were subjected to procedures of reducing the blood supply either of the esophageal or the gastric stump (group II and group III, respectively), followed by single-layer esophagogastric anastomoses using interrupted 5-0 polypropylene sutures. Ten days after operation, all the rats were killed and the anastomotic sites excised for measurement of the inner diameter, tensile strength, and hydroxyproline concentration. RESULTS: Healing of the esophagograstric anastomosis was obtained in all the rabbits but one with anastomotic leakage in group I and one with perforation of the gastric fundus in group III. The anastomotic inner diameters were similar in all the three groups, whereas the tensile strength and hydroxyproline concentration at the anastomoses decreased in group III in comparison with the other two groups (P<0.05) that had similar measurements (P>0.05). CONCLUSIONS: Extended length of the free esophageal stump does not significantly affect anastomotic healing as decrease of blood supply in the gastric stump.  相似文献   
109.
本文应用电力载波技术,实现远端时钟的中央控制。系统通过电力载波芯片从电力线上收发控制信号,中央控制端发送的时钟校准信号到电力线网络,接人网络的远端时钟接收到校准信号后,由微处理器解析数据调整受控端时钟显示,从而实现时钟的中央控制。  相似文献   
110.
用放射免疫法测定产后40天和60天乳母血清泌乳素基础水平和吸吮后泌乳素最大反应性增值,发现其与乳母泌乳量、婴儿吸吮频率、吸吮时间之间均不存在正相关关系,推测引起泌乳素分泌除吸吮外,还存在其他机理。  相似文献   
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