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81.
82.
Jiang He Mary Rusckowski Yi Wang Shuping Dou Xinrong Liu Surong Zhang Guozheng Liu Donald J. Hnatowich 《Molecular imaging and biology》2007,9(1):17-23
Objective Pretargeting with radioactivity has significantly improved tumor to normal tissue radioactivity ratios over conventional antibody
imaging in both animal studies and clinical trials. This laboratory is investigating DNA analogues such as phosphorodiamidate
morpholinos (MORFs) for pretargeting using technetium-99m (99mTc) for detection. However, the unique properties of fluorescence activation and quenching combined with oligomers with their
unique properties of hybridization may be particularly useful when used together for pretargeting with optical detection.
The use of linear fluorophore-conjugated oligomer duplexes have been little used in animals, and to our knowledge, have not
previously been considered for pretargeting applications.
Methods A MORF/cDNA pair was selected such that when hybridized, the fluorescence of the Cy5.5-conjugated 25 mer MORF (Cy5.5–MORF25)
is inhibited with a BHQ3-conjugated 18 mer complementary DNA (BHQ3–cDNA18). The short BHQ3–cDNA18 was selected to dissociate
in the presence of a long cMORF25 in the pretargeted tumor, thus releasing the inhibitor from the Cy5.5 emitter. In this manner,
the Cy5.5 fluorescence will be inhibited everywhere but in the target. The dissociation was first examined in vitro by adding the duplex to the cMORF25 both in solution and immobilized on polystyrene microspheres and by surface plasmon resonance
(SPR). Thereafter, biotinylated cMORF25 immobilized on streptavidin polystyrene microspheres were administered intramuscularly
in one thigh of hairless SKH-1 mice as target while an identical weight of the identical microspheres but without the cMORF25
was administered in the contralateral thigh as control. The animals then received IV the Cy5.5–MORF25/BHQ3–cDNA18 duplex or
equal molar dosage of single-chain Cy5.5–MORF25 and were imaged.
Results The SPR studies showed that the immobilized cDNA18 rapidly captured the flowing MORF25 to provide a duplex with a slow dissociation
rate constant. Furthermore, when cMORF25 was next allowed to flow over the now immobilized duplex, the cDNA18 was unable to
prevent dissociation of the heteroduplex and the formation and release of the cMORF25-MORF25 homoduplex. Images of animals
obtained soon after receiving the Cy5.5–MORF25 singlet showed intense whole body fluorescence obscuring the target thigh.
However, only 5 minutes after receiving the Cy5.5–MORF25/BHQ3–cDNA18 duplex, the target thigh was clearly visible along with
only the kidneys.
Conclusions This first study of optical pretargeting provides a proof of concept that oligomer pretargeting found to be useful with radioactivity
detection is applicable with fluorescent detection as well. In addition, our results demonstrate that by using linear oligomers
for optical pretargeting, chain lengths (and base sequences) may be manipulated to provide duplexes with stabilities and fluorescence
inhibition optimized for pretargeting and other in vivo applications of optical imaging. 相似文献
83.
目的 探讨超声刀在腹腔镜胆囊切除术中的应用价值。方法 将 86例腹腔镜胆囊切除术患者随机分为超声刀组 ( 3 4例 )与电刀组( 5 2例 ) ,分别使用超声刀与单极电刀完成手术 ,比较术中及术后的效果。结果 86例手术顺利完成 ,无中转开腹。手术时间分别为 ( 4 5±7)min和 ( 62± 9)min(P <0 0 1) ,术中出血量分别为 ( 5± 0 .8)ml和 ( 2 0± 5 )ml(P <0 .0 1) ,术后肠道功能恢复时间分别为 ( 2 0± 4)h和 ( 2 4±6)h(P <0 0 1) ,两组均无胆瘘发生。结论 超声刀在腹腔镜胆囊切除术中较电刀更快捷 ,出血更少 ,术后恢复更快 相似文献
84.
目的:分析肾移植后免疫抑制剂对长期存活的影响,寻找移植后不同时间合适的免疫抑制用药方案及其用药剂量。 方法:对肾移植一年以上、肾功能正常的497例患者进行5年连续随访。根据移植后2、3、5年的不同免疫抑制用药将患者分为三联、二联、传统二联治疗三组。统计各组的排异发生率,排异和无排异患者免疫抑制用药的种类、剂量及CsA浓度,对排异患者追踪排异发生前12个月内的药物更动情况。 结果:肾移植后2、3、5 相似文献
85.
Anatomic and spiral computed tomographic study of the genial tubercles for genioglossus advancement.
Shan Kai Yin Hong Liang Yi Wen Ying Lu Jian Guan Hong Min Wu Zhen Yu Cao Dong Zhen Yu Yan Yan Huang Chun Gen Wu 《Otolaryngology--head and neck surgery》2007,136(4):632-637
OBJECTIVE: To measure and compare Chinese mandibular genial tubercles measured anatomically and with computed tomography (CT). STUDY DESIGN AND SETTING: Spiral CT scans were taken of 40 adult human skulls; the superior genial spines were measured using anatomic and CT methods. RESULTS: The height and width of the superior genial spines, mandible thickness, and distance from the menton to the inferior and superior margins of the superior genial spines were 5.82 +/- 0.71, 6.98 +/- 1.35, 11.95 +/- 1.59, 11.08 +/- 2.05, and 16.91 +/- 2.30 mm from anatomic measurements and 6.17 +/- 0.71, 7.01 +/- 1.13, 12.19 +/- 1.64, 10.41 +/- 1.55, and 15.73 +/- 2.12 mm using spiral CT, respectively. The anatomic and CT measurements were correlated. CONCLUSION: Spiral CT of the genial tubercles can help locate the osteotomy in genioglossus advancement. SIGNIFICANCE: This study acquired reference data on Chinese genial tubercles demonstrating that CT measurements of the genial tubercles reflect their anatomy, which should allow accurately locate the osteotomy. 相似文献
86.
Anders Bergdahl Torun Nilsson Xiang Ying Sun Thomas Hedner Lars Edvinsson 《European journal of pharmacology》1998,360(2-3):165-173
The aim of the present study was to elucidate if the potentiating effect of neuropeptide Y on various vasoactive agents in vitro is (1) altered in mesenteric arteries from rats with congestive heart failure and (2) mediated by the neuropeptide Y Y1 receptor. The direct vascular effects of neuropeptide Y and its modulating effects on the contractions induced by endothelin-1-, noradrenaline-, 5-hydroxytryptamine (5-HT)-, U46619-(9, 11-dideoxy-11, 9-epoxymethano-prostaglandin F2) and ATP, and acetylcholine-induced dilatations were studied in the presence and absence of the neuropeptide Y Y1 antagonist, BIBP3226 (BIBP3226{(R)-N2-(diphenylacetyl)-N-[(4-hydroxyphenyl)methyl]-
-arginine-amide}). Neuropeptide Y, per se, had no vasoactive effect in the arteries. The potency of endothelin-1 was significantly decreased in congestive heart failure rats. Neuropeptide Y and neuropeptide Y-(13–36) potentiated the endothelin-1-induced contraction in congestive heart failure mesenteric arteries. In 20% of the congestive heart failure rats, sarafotoxin 6c induced a contraction of 31±4%. Neuropeptide Y also potentiated U46619- and noradrenaline-induced contractions but not 5-HT-induced contractions in congestive heart failure arteries. In sham-operated animals neuropeptide Y potentiated noradrenaline- and 5-HT-induced contractions. These potentiations were inhibited by BIBP3226. Acetylcholine induced an equipotent relaxation in both groups which was unaffected by neuropeptide Y. In conclusion, neuropeptide Y responses are altered in congestive heart failure rats. The potentiating effect differs between vasoactive substances. Neuropeptide Y Y1 and non-neuropeptide Y1 receptors are involved. 相似文献
87.
Ultraviolet Laser-Induced Fluorescence Spectroscopy Diagnosis of Human Stomach Malignant Tissues 总被引:2,自引:0,他引:2
To evaluate the potential of laser-induced autofluorescence spectroscopy for the detection of premalignant lesions of human
stomach, fluorescence properties of stomach tissues have been investigated in vitro and in vivo. A specially made optical
fibre probe and the multichannel fluorescence collection system have been used successfully in our research.
Paper received 26 June 1997; accepted in revised form 31 October 1997. 相似文献
88.
Dara L. Kraitchman Norbert Wilke Erik Hexeberg Michael Jerosch-Herold Ying Wang Todd B. Parrish Cheng-Ning Chang Yi Zhang Robert J. Bache Leon Axel 《Magnetic resonance in medicine》1996,35(5):771-780
MRI studies of first-pass contrast enhancement with polylysine-Gd-DTPA and myocardial tagging using spatial modulation of magnetization (SPAMM) were performed to assess the feasibility of a combined regional myocardial blood flow and 2D deformation exam. Instrumented closed-chest dogs were imaged at a baseline control state (Cntl) followed by two interventions: moderate coronary stenosis (St) achieved by partial occlusion of the left anterior descending (LAD) and moderate coronary stenosis with dobutamine loading (StD). Hypoperfusion of the anterior region (ANT) of the myocardium (LAD distribution) relative to the posterior wall (POS) based on the upslope of the signal intensity time curve from the contrast-enhanced MR images was demonstrated only with dobutamine loading (ANT:POS Cntl=1.077 ± 0.15 versus ANT:POS StD=0.477 ± 0.11, P<0.03) and was confirmed with radio-labeled microspheres measurements (ANT:POS Cntl=1.18 ± 0.2 ml/min/g versus ANT:POS StD=0.44 ± 0.1 ml/min/g; P<0.002). Significant changes in regional myocardial shortening were only seen in the StD state (P<0.02); the anterior region showed impaired myocardial shortening with dobutamine loading (P=NS), whereas the nonaffected POS region showed a marked increase in shortening when compared with Cntl (Cntl=0.964 ± 0.02 versus StD=0.884 ± 0.03; P<0.001). These results demonstrate that an integrated quantitative assessment of regional myocardial function and semiquantitative assessment of myocardial blood flow can be performed noninvasively with ultrafast MRI. 相似文献
89.
应用食道心房调博缩测定健康小儿窦房结功能,以了解西宁地区正常数值与平原地区进行对比。选择27例健康小儿,将F6二级电极导管从鼻腔送入,定位地食道心电图最大正负双相P波处,采用苏州东方电子仪器厂生产的DF-3A型心脏电生理治疗仪进行检查,从而作出诊断。 相似文献
90.
在竹叶及其提取物中检出了一种特殊的非蛋白氨基酸δ-OH-Lys,为了解其生物学意义,用化学发光法和电子自旋共振法(ESR)对δ-OH-Lys和Lys清除超氧阴离子自由基(O2-)的能力作了比较,结果表明赖氨酸在δ位羟化以后,抗活性氧自由基的活性有了显著提高。 相似文献