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111.
Fast CT-PRESS-based spiral chemical shift imaging at 3 Tesla. 总被引:2,自引:0,他引:2
Dirk Mayer Dong-Hyun Kim Elfar Adalsteinsson Daniel M Spielman 《Magnetic resonance in medicine》2006,55(5):974-978
A new sequence is presented that combines constant-time point-resolved spectroscopy (CT-PRESS) with fast spiral chemical shift imaging. It allows the acquisition of multivoxel spectra without line splitting with a minimum total measurement time of less than 5 min for a field of view of 24 cm and a nominal 1.5x1.5-cm2 in-plane resolution. Measurements were performed with 17 CS encoding steps in t1 (Deltat1=12.8 ms) and an average echo time of 151 ms, which was determined by simulating the CT-PRESS experiment for the spin systems of glutamate (Glu) and myo-inositol (mI). Signals from N-acetyl-aspartate, total creatine, choline-containing compounds (Cho), Glu, and mI were detected in a healthy volunteer with no or only minor baseline distortions within 14 min on a 3 T MR scanner. 相似文献
112.
Reem Haj-Ali BDS DDS MS ; Mary Walker DDS PhD ; Karen Williams PhD ; Yong Wang PhD ; Paulette Spencer DDS PhD 《Journal of prosthodontics》2006,15(2):82-88
PURPOSE: The purpose of this study was to compare the dentin/adhesive interfacial characteristics when bonding to noncarious as well as caries-affected dentin. MATERIALS AND METHODS: Seven extracted, unerupted, third molars were sectioned into halves. Artificial caries was created on one-half of each tooth, leaving the other half as a control. Dentin surfaces were treated with UNO adhesive according to the manufacturer's instructions for the wet-bonding technique and under environmental conditions present in the oral cavity. Dentin/adhesive interface sections of each half-tooth were stained with Goldner's trichrome, a classic bone stain, and examined using light microscopy. The width of exposed collagen was measured directly from photomicrographs, and adhesive penetration was analyzed qualitatively. RESULTS: The degree and extent to which the adhesive encapsulated the demineralized dentin matrix were reflected in the color difference in the stained sections with the noncarious dentin sections showing a degree of collagen encapsulation superior to that of the caries-affected dentin sections. The overall mean widths of exposed collagen were significantly (p < or = .05) greater at the caries-affected dentin/adhesive interface, 8.6 (1.7) microm, as compared with those at the noncarious dentin/adhesive interface, 6.0 (1.5) microm. CONCLUSIONS: The morphologic characteristics of the caries-affected dentin/interface suggest an increase in the exposed collagen zone and a decrease in the quality of the adhesive infiltration when compared with noncarious dentin. The evidence suggests that dentin substrate characteristics have a significant effect on the dentin/adhesive interface structure. 相似文献
113.
Bi-Hua BIE Yong CHEN Zhi-Qi ZHAO Institute of Neurobiology Fu-Dan University Shanghai China Institute of Shanghai Physiology Chinese Academy of Sciences Shanghai China 《中国神经科学杂志》2006,(2)
Objective Ligustrazine, also named as tetramethylpyrazine, is a compound purified from Ligusticum chuanxiong hort and has ever been testified to be a calcium antagonist. The present investigation was to determine the antinoci-ceptive effect of ligustrazine and, if any, the peripheral ionic mechanism involved. Methods Paw withdrawal Latency ( PWL) to noxious heating was measured in vivo and whole-cell patch recording was performed on small dorsal root ganglion (DRG) neurons. Results Intraplantar injection of ligustrazine (0.5 mg in 25μl) significantly prolonged the withdrawal latency of ipsilateral hindpaw to noxious heating in the rat. Ligustrazine not only reversibly inhibited high-voltage gated calcium current of dorsal root ganglion (DRG) neuron in dose-dependent manner with IC50 of 1.89 mmol/L, but also decreased tetrodotoxin (TTX) -resistant sodium current in relatively selective and dose-dependent manner with IC50 of 2.49 mmol/L. Conclusion The results suggested that ligustrazine could elevate the threshold of thermal nociception through inhibiting the high-voltage gated calcium current and TTX-resistant sodium current of DRG neuron in the rat. 相似文献
114.
经皮椎弓根技术治疗胸腰椎骨折的临床探讨 总被引:2,自引:0,他引:2
目的:探讨微创经皮椎弓根螺钉内固定手术治疗胸腰椎骨折的可行性及其疗效。方法:20例胸腰椎骨折病例,男13例,女7例;年龄28~65岁,平均48·2岁。其中16例损伤平面以下无神经功能损害、无双下肢和大小便障碍;4例有不同程度的脊髓损伤,按Frankel分级:C级1例,D级3例。在C形臂X线的定位下确定需要固定的椎弓根根部,做4个1·5cm长的切口,固定与复位均在4个小切口内完成。结果:所有病例均获随访,时间9~18个月,平均15个月。术后患者椎体高度均有不同程度恢复,椎体后凸畸形获得不同程度矫正。手术时间约1·5h,出血量约80ml。结论:微创经皮椎弓根螺钉内固定手术操作简便、安全可靠,具有创伤小、出血少、疼痛轻、恢复快、住院时间短等优点。 相似文献
115.
H J Kim C H Kang Y T Kim S-W Sung J H Kim S M Lee C-G Yoo C-T Lee Y W Kim S K Han Y-S Shim J-J Yim 《The European respiratory journal》2006,28(3):576-580
Although surgical lung resection could improve prognosis in some patients with multidrug-resistant tuberculosis (MDR-TB), there are no reports on the optimal candidates for this surgery. The aim of the present study was to elucidate the prognostic factors for surgery in patients with MDR-TB. Patients who underwent lung resection for the treatment of MDR-TB between March 1993 and December 2004 were included in the present study. Treatment failure was defined as greater than or equal to two of the five cultures recorded in the final 12 months of treatment being positive, any one of the final three cultures being positive, or the patient having died during treatment. The variables that affected treatment outcomes were identified through univariate and multivariate logistic regression analysis. In total, 79 patients with MDR-TB were included in the present study. The treatment outcomes of 22 (27.8%) patients were classified as failure. A body mass index <18.5 kg x m(-2), primary resistance, resistance to ofloxacin and the presence of a cavitary lesion beyond the range of the surgical resection were associated with treatment failure. Low body mass index, primary resistance, resistance to ofloxacin and cavitary lesions beyond the range of resection are possible poor prognostic factors for surgical lung resection in multidrug-resistant tuberculosis patients. 相似文献
116.
足部骨筋膜室综合征早期诊断与治疗 总被引:2,自引:0,他引:2
目的:探讨足部骨筋膜室综合征早期诊断与治疗结果。方法:1998年1月-2003年12月收治15例足骨筋膜室综合征患者(均为男性:年龄15~55岁,平均32岁),行足背双切口减压4例,足底内侧减压9例,足内外两侧减压2例。1周后行减张缝合或植皮术。结果:15例随访9~24个月,12例恢复佳,足运动感觉正常;2例有足底感觉减退、足趾麻木;1例遗留前足挛缩、无力,足趾麻木。无爪形趾及功能障碍者。结论:足损伤后,Whiteside法测定组织间隙压力是诊断足骨筋膜室综合征的可靠方法。治疗时足部如有骨折、血肿者,骨筋膜室减张切口,宜选择足底内侧切开效果较好。 相似文献
117.
Sung Woo Lee Sung Hyuk Choi Yunsik Hong Wanbae Kim 《European journal of emergency medicine》2006,13(2):117-118
Generally, a computed tomography scan is conducted for the diagnosis of stroke in the emergency department, because these scans are easier and faster in the detection of stroke. If there are no signs of hemorrhage on computed tomography scan, an ischemic stroke is diagnosed and treated accordingly. A magnetic resonance imaging scan may be taken in order to verify ischemic stroke. This process may lead to improper treatment and is time consuming. To address this situation, case studies are presented in which magnetic resonance imaging diffusion-weighted imaging and gradient recalled echo were performed to detect hemorrhagic and ischemic stroke and particularly, subarachnoid hemorrhage, which is undetectable with a computed tomography scan. 相似文献
118.
Pulmonary Lophomonas blattarum infection in patients with kidney allograft transplantation 总被引:3,自引:0,他引:3
Yong Wang Zheng Tang Shuming Ji Zhen Zhang Jinsong Chen Zhen Cheng Dongrui Cheng Zhihong Liu Leishi Li 《Transplant international》2006,19(12):1006-1013
The aim of the study was to analyse the clinical manifestation and management of pulmonary Lophomonas blattarum infection in four allograft transplantation recipients retrospectively. Four patients with pulmonary L. blattarum infection were diagnosed by using Fiberoptic bronchoscopy (FOB) and bronchoalveolar lavage (BAL) examination. Their clinical manifestation and management are summarized. Four cases of pulmonary L. blattarum were found during the period from the second month to the third month after transplantation. Concurring infection by other pathogens was found in three of them. Common initial symptoms included fever (>38 degrees C) without cough and breathlessness. Lower lobe shadowing could be found on chest X-ray. Body temperature decreased to the normal range in three patients and to 37.5 degrees C in the other one, after intravenous injection of metronidazole and tapering immunosuppressant. Radiological examination confirmed improved health condition of the patients afterwards. Two patients received repeated FOB and only dead L. blattarum was found. Pulmonary L. blattarum infection in allograft transplant recipients carry relatively obscure initial symptoms. Possible L. blattarum infection needs to be screened in post-transplantation pulmonary infection patients with similar symptoms, especially in those who respond poorly to anti-infection treatment. Microscopic examination of BAL fluid can help to identify pulmonary L. blattarum infection and metronidazole is an ideal treatment choice. 相似文献
119.
120.
Twenty-five women receiving sedation for outpatient hysteroscopic polypectomy were injected with 0.25% bupivacaine 10 mL (paracervical group) and another 25 received the same volume of saline (control group) at the cervical fornix. Both groups were given target-controlled propofol sedation during the procedure. More propofol (mg/min) was needed for adequate anesthesia in the control group compared to the paracervical group (6.5 versus 4.6). In addition, the postoperative pain scores were lower in the paracervical group than in the control group. Hemodynamic changes and postoperative side effects were similar in the two groups. This prospective, randomized, double-blind, placebo-controlled study confirmed the effective use of paracervical blocks. This approach has the effect of reducing the amount of intraoperative propofol and decreasing postoperative pain in outpatient hysteroscopic surgery. 相似文献