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71.
In vivo multiple-mouse imaging at 1.5 T.   总被引:3,自引:0,他引:3  
A multiple-mouse solenoidal MR coil was developed for in vivo imaging of up to 13 mice simultaneously to screen for tumors on a 1.5 T clinical scanner. For the coil to be effective as a screening tool, it should permit acquisition of MRIs in which orthotopic tumors with diameters >2 mm are detectable in a reasonable period of time (<1 hr magnet time) and their sizes accurately measured. Using a spin echo sequence, we demonstrated that this coil provides sufficient sensitivity for moderately high resolution images (156-176 microm in plane-resolution, 1.5 mm slice thickness). This spatial resolution permitted detection of primary brain tumors in transgenic/knockout mice and orthotopic xenografts. Brain tumor size as measured by MRI was correlated with size measured by histopathology (P < 0.001). Metastatic tumors in the mouse lung were also successfully imaged in a screening setting. The multiple mouse coil is simple in construction and may be implemented without any significant modification to the hardware or software on a clinical scanner.  相似文献   
72.
综合医院精神科会诊患者失眠的临床研究   总被引:3,自引:0,他引:3  
目的:探讨综合医院精神科会诊患者失眠的临床特征及与其它精神障碍的关系。方法:对168例精神科会诊患者进行分析。结果:128例(76、2%)会诊患者有失眠.其中61.7%(79/128)为慢性失眠。原发性失眠仅占5.5%(7/128),85.1%(109/128)是与其它精神障碍有关的失眠。常见的精神障碍诊断为焦虑障碍、心境障碍和谵妄。60.9%的失眠患者在会诊前得到了处理。结论:应对临床医师进行精神卫生教育,提高他们对失眠等常见精神障碍的识别和处理能力。  相似文献   
73.
Eighteen Coopworth ewe lambs were divided into three groups based on the initial cystourethrogram and cystometry findings at 5 – 7 weeks of age: group 1, 6 lambs with spontaneous low-pressure bilateral vesicoureteric reflux (VUR) on bladder filling were used to study the natural history of reflux; group 2, 5 lambs with no VUR detected were used to establish an experimental model of bilateral VUR using an unroofing surgical procedure; group 3, 7 lambs with spontaneous VUR detected during micturition had the same surgical procedure to increase the degree of VUR. All three animal groups were followed for 4 – 10 months. Spontaneous VUR was demonstrated in 13 of 18 lambs (25/36 ureters). The presence and severity of spontaneously occurring reflux in group 1 lambs diminished with increasing age. VUR was created successfully in group 2 and increased in degree in group 3 animals. The only significant histological finding in all three animal groups with grades II and III VUR was distal renal tubular dilatation. The sheep is a useful and readily available animal for studying VUR. During 4 – 10 months of follow-up, sterile reflux without bladder outflow obstruction resulted in distal renal tubular dilatation, but no renal parenchymal damage. Received April 17, 1997; received in revised form August 5, 1997; accepted August 21, 1997  相似文献   
74.
从2105例胃癌癌旁组织中找出微小腺癌31例(〈0.1cm),观察其组织发生的特征,发现胃腺癌的发生有8种形式:①腺颈部干细胞癌变;②表面上皮癌变;③腺上皮癌变;④肠化生上皮癌变;⑤微腺囊癌变;⑥溃疡边缘上皮癌变;⑦扁平腺瘤癌变;⑧贲门交界处柱状上皮癌变。  相似文献   
75.
“C”型曲线的中耳声学特性改变与鼓室积液的关系   总被引:10,自引:2,他引:8  
对40耳声导抗检查为“C”型曲线患耳进行中耳系统共振频率点测试并进行鼓室穿刺抽液,结果表明:共振频率点低于600Hz,患耳鼓室积液阳性率为82.1%,高于600Hz患者鼓室和液阳性率16.7%,提示依据鼓室导抗图和共振频率点测定可初步判断“C”型曲线患耳鼓室积液的可能.  相似文献   
76.
Cross relaxation between macromolecular protons and water protons is known to be important in biologic tissue. In magnetic resonance (MR) imaging sequences, selective saturation of the characteristically short T2 macromolecular proton pool can produce contrast called magnetization transfer contrast, based on the cross-relaxation process. Selective saturation can be achieved with continuous wave irradiation several kilohertz off resonance or short, intense 0° pulses on resonance. The authors analyze 0° binomial pulses for T2 selective saturation, present design guidelines, and demonstrate the use of these pulses in spin-echo imaging sequences in healthy volunteers and patients. Using the phenomenologic Bloch equations modified for two-site exchange, the authors derive the analytic expressions for water proton relaxation under periodic pulsed saturation of the macromolecular protons. This relaxation is shown to be monoexpo-nential, with a rate constant dependent on the saturation pulse repetition rate and the individual and cross-relaxation rates.  相似文献   
77.
Immunoluminometric assays for lactoferrin and elastase-alpha 1-proteinase inhibitor complexes were developed using solid-phase methodology, which has already been published from this laboratory. The aim of the study was to develop a rapid method to see whether elevated granulocyte activity was present in the lung, as for example in neonatal sepsis. The lactoferrin assay gave reliable results within 30 minutes, the elastase-alpha 1-proteinase inhibitor complexes, within 5 hours. The correlation between both analytes was good, so that the lactoferrin assay could replace the elastase-alpha 1-proteinase inhibitor assay in emergency cases. The lactoferrin assay was used for rapid answer, the elastase-alpha 1-proteinase inhibitor complex assay for "fine" monitoring of the progress of the disease. Both assays could be used to measure concentrations in plasma or bronchoalveolar lavage using a 10 microliters sample. Plasma for the elastase-alpha 1-proteinase inhibitor complex determination had to be diluted 1:50 before being assayed. Only EDTA plasma was used in the assay, as either heparin plasma or serum resulted in granulocyte destruction, thus giving rise to elevated, and non-reproducible results. The results from bronchoalveolar lavage show an excellent correlation between elastase-alpha 1-proteinase inhibitor complexes and lactoferrin. No interference was seen from lipaemic or icteric plasma samples. Results from haemolytic samples i.e. where lysis of erythrocytes and leukocytes had occurred, had to be treated with care if no clinical indication of intravascular haemorrhage was present. The assays lend themselves to perinatal diagnosis, as the total volume of plasma or lavage needed is theoretically under 50 microliters, i.e. ethically acceptable for regular monitoring of neonates.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
78.
本实验用纯系CFW小鼠与Wistar大鼠建立“虚证”模型。以环核苷酸系统反应性为指标观察了肉桂挥发油的作用。通过气相色谱及气质联用等方法研究表明,本实验所提取的挥发油中桂皮醛含量约为92%。肉桂挥发油可显著降低“阳虚”——甲状腺素缺乏(甲减)模型升高了的cGMP系统反应性而使其降低了的耗O_2率升高;这是一种治疗作用。肉桂挥发油可显著升高“阴虚”——甲状腺素过多(甲亢)模型已升高了的cAMP系统反应性并使其升高了的耗O_2率进一步升高,这是一种恶化作用。这两种作用与中医对症治疗的原则是一致的。  相似文献   
79.
Hu WL  Hesse M 《Planta medica》1988,54(3):235-236
From the leaves of MELODINUS ACUTIFLORUS a new alkaloid, rhazicine N-oxide ( 2), and two known compounds, deacetylakuammiline ( 3) and 16- EPI-rhazinaline ( 4) were isolated. The structure of 2 was determined by spectral analysis and chemical correlation with rhazicine ( 1).  相似文献   
80.
We solve a discrete version of the classic Plateau problem, which asks for a minimal surface spanning a given curve. Our algorithm is based on a network-flow formulation that finds minimal slabs, intuitively corresponding to minimal "surfaces" of prescribed thickness. We let the slab thickness approach zero in order to obtain the desired minimal surface.  相似文献   
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