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N-Alkoxycarbonylaminodicarboxylic acids were reacted in dichloromethane with N-ethyl-N′-(dimethylaminopropyl)carbodiimide hydrochloride, and with methyl chloroformate in the presence of N-methylmorpholine. Removal of secondary products by washing the mixtures with aqueous solutions gave good yields of the pure crystalline internal anhydrides. Anhydrides of N-benzyloxycarbonyl- (Z) and N-9-fluorenylmethoxycarbonyl-(Fmoc) L-glutamic and L-aspartic acids and of N-tert.-butoxycarbonyl-L-aspartic acid were prepared in this way. The compounds were shown to be amenable to normal phase high-performance liquid chromatography (NP-HPLC) on a CN-column using tert.-butanol-hexane as solvent. The products of the reactions of Z- and Fmoc-glutamic acid with hot acetic anhydride were examined by nuclear magnetic resonance and NP-HPLC before and after methanolysis in an attempt to establish if any of the corresponding pyroglutamates were formed. The reaction of Fmoc-chloride with Fmoc-glutamate was examined for the same reason. It is concluded that the side product generated during the reaction of Fmoc-chloride with glutamic acid which is used for analysis of the latter is the N-protected internal anhydride and not the pyroglutamate as reported in the literature. 相似文献
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目的 探讨利用吻合器通过切除直肠下端黏膜 ,肛垫悬吊治疗脱垂性痔的手术疗效和安全性。方法 应用该术式治疗 31例Ⅲ、Ⅳ度环形脱垂痔患者 ,男 18例 ,女 13例 ,平均年龄 49岁 ,痔脱垂病史 7年 ,11例曾接受硬化剂治疗 ,3例有手术治疗史。结果 2 1例术后立即完全回缩 ,8例术后第 3天后完全回缩 ,2例未能完全回缩。无术后肛门疼痛及肛门部水肿 ,无吻合口出血、尿潴留。术后平均住院 4d ,随访 2~ 2 4个月。术后无大便失禁、肛门狭窄、复发。结论 经吻合器直肠下端黏膜环形切除肛垫悬吊术治疗脱垂性痔具有疗效显著、手术后并发症少、住院时间短等特点。 相似文献
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AKIHISA FUKUDA TORU KAJIYAMA HIROYUKI KISHIMOTO HIROAKI ARAKAWA HITOSHI SOMEDA MASAHIKO SAKAI HIROSHI SENO TSUTOMU CHIBA 《Journal of gastroenterology and hepatology》2006,20(1):46-50
Background: Bleeding is one of the main symptoms of internal hemorrhoids. However, the conventional Goligher's classification of internal hemorrhoids does not consider the severity of bleeding. We intended to establish a useful method for evaluating internal hemorrhoids using a colonoscope that reflected the severity of the symptoms.
Methods: Using a colonoscope in the retroflexed and forward viewing position, 104 patients with symptomatic internal hemorrhoids were evaluated based on the criteria of range, form and red color signs (RCS). Range was determined by the circumferential distribution of internal hemorrhoids and scaled from 0 to 4. Form was determined by size and scaled from 0 to 2. The presence of RCS was also evaluated. Symptoms were determined by interview and scaled from 0 to 3. Patients were treated by endoscopic band ligation (EBL) and were examined endoscopically before and 4 weeks after the treatment.
Results: Before the treatment, range, form and RCS were significantly correlated to bleeding ( P < 0.01), and form was significantly correlated to prolapse ( P < 0.05). The endoscopic classification scores at 4 weeks after EBL improved significantly (range from 3.25 ± 0.05–0.56 ± 0.08 [ P < 0.01] and form from 2.81 ± 0.04–0.56 ± 0.07 P < 0.01).
Conclusion: The new endoscopic classification of internal hemorrhoids proved to be closely correlated to symptoms, particularly bleeding, and thus highly useful in evaluating the effectiveness of the treatment. 相似文献
Methods: Using a colonoscope in the retroflexed and forward viewing position, 104 patients with symptomatic internal hemorrhoids were evaluated based on the criteria of range, form and red color signs (RCS). Range was determined by the circumferential distribution of internal hemorrhoids and scaled from 0 to 4. Form was determined by size and scaled from 0 to 2. The presence of RCS was also evaluated. Symptoms were determined by interview and scaled from 0 to 3. Patients were treated by endoscopic band ligation (EBL) and were examined endoscopically before and 4 weeks after the treatment.
Results: Before the treatment, range, form and RCS were significantly correlated to bleeding ( P < 0.01), and form was significantly correlated to prolapse ( P < 0.05). The endoscopic classification scores at 4 weeks after EBL improved significantly (range from 3.25 ± 0.05–0.56 ± 0.08 [ P < 0.01] and form from 2.81 ± 0.04–0.56 ± 0.07 P < 0.01).
Conclusion: The new endoscopic classification of internal hemorrhoids proved to be closely correlated to symptoms, particularly bleeding, and thus highly useful in evaluating the effectiveness of the treatment. 相似文献
26.
双相情感障碍混合相临床特征对照研究 总被引:2,自引:0,他引:2
目的:了解双相情感障碍混合相的临床特征。方法:收集42例双相情感障碍混合相患者(混合组)与93例无混合发作的双相情感障碍躁狂相的患者(躁狂组)住院治疗的临床资料进行对比。结果:混合组年龄稍低,多见于女性和独身者,性格多为外向型或中间型,首次发作多为抑郁,多伴有精神病性症状及自杀意念和企图。多元逐步回归分析提示,混合发作与自杀意念和企图、性格、性别、首次发作形式有显著的相关性。混合组具有易被误诊、住院时间长、疗效较差的特点。结论:双相情感障碍混合相临床表现具有特殊性、严重性及相应的难治性,应加强重视。 相似文献
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Analysis of count data from clinical trials using mixed effect analysis has recently become widely used. However, algorithms
available for the parameter estimation, including LAPLACE and Gaussian quadrature (GQ), are associated with certain limitations,
including bias in parameter estimates and the long analysis runtime. The stochastic approximation expectation maximization
(SAEM) algorithm has proven to be a very efficient and powerful tool in the analysis of continuous data. The aim of this study
was to implement and investigate the performance of a new SAEM algorithm for application to count data. A new SAEM algorithm
was implemented in MATLAB for estimation of both, parameters and the Fisher information matrix. Stochastic Monte Carlo simulations
followed by re-estimation were performed according to scenarios used in previous studies (part I) to investigate properties
of alternative algorithms (Plan et al., 2008, Abstr 1372 []). A single scenario was used to explore six probability distribution models. For parameter estimation, the relative bias
was less than 0.92% and 4.13% for fixed and random effects, for all models studied including ones accounting for over- or
under-dispersion. Empirical and estimated relative standard errors were similar, with distance between them being <1.7% for
all explored scenarios. The longest CPU time was 95 s for parameter estimation and 56 s for SE estimation. The SAEM algorithm
was extended for analysis of count data. It provides accurate estimates of both, parameters and standard errors. The estimation
is significantly faster compared to LAPLACE and GQ. The algorithm is implemented in Monolix 3.1, (beta-version available in
July 2009). 相似文献
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F. Pott F. S. Larsen E. Ejlersen P. Linkis L. G. Jrgensen N. H. Secher 《Clinical physiology and functional imaging》1995,15(2):119-130
Summary. During transplantation of the liver cerebral perfusion was monitored by transcranial Doppler determined middle cerebral artery mean flow velocity (Vmean) and pulsatility index (PI) in six fulminant hepatic failure patients and 11 patients with chronic liver disease. In both groups of patients Vmean, PI and central haemodynamic variables were recorded during (1) the last preanhepatic hour; (2) the anhepatic phase; (3) the first 15 min of reperfusion; and (4) for the following 45 min of reperfusion. No significant differences were detected between the two groups of patients with respect to changes of variables with time. The Vmean (40±13 cm s-1 [mean±SD]), thoracic electrical impedance (TI) (30±7 Ohm), heart rate (97±19 beats min-1), mean arterial pressure (84±9 mmHg) and arterial carbon dioxide tension (PaCO2, 4.5±0.4 kPa) remained stable in the anhepatic phase, while cardiac output (CO, 7.6±2.7 to 5.4±1.41 min-1), stroke volume (SV, 79±26 to 56±15 ml) and PI (1.2±0.3 to 0.9±0.2) decreased (P<0.05). During reperfusion, CO (9.9±4.01 min-1), SV (105±40 ml), PaCO2 (5.5±0.6 kPa), Vmean (57±17 cm s-1) and PI (1.2±0.2) became elevated. Taken together, during the anhepatic phase of the liver transplantation a maintained central blood volume as indicated by the constant TI served for a stable blood pressure and in turn cerebral perfusion, whereas revascularization of the graft increased cerebral perfusion concomitant with an elevated carbon dioxide tension. 相似文献