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101.
An X-ray diffraction study has been carried out on single crystals of two symmetrical ureines (N,N′-diiopropylurea and the familiar N,N′-dicyclohexylurea) and one unsymmetrical ureine (N-tert.-butyl.N′-methylurea). The presence/absence of intermolecular H-bonds in the crystal state has been compared to the situation assessed in solution by 1H n.m.r. It was shown by i.r. absorption that soluble ureines may disrupt intermolecular (peptide)N—H- O=C(peptide) H-bonds in methylene chloride, a point of practical interest, particularly in solid-phase peptide synthesis.  相似文献   
102.
Tryptic digestion of the mouse epidermal growth factor (mEGF) and the chromatographic separation of its proteolytic fragments by RP-HPLC affords the isolation of the pure hormone, of its 1–48 (Des(49–53)mEGF) and 1–45 (Des(46–53)mEGF) derivatives, and of the carboxyl-terminal pentapeptide W49–W50-E51-L52-R53. Kinetics of mEGF proteolytic degradation follows a two-state time-course: native mEGF being converted into Des(49–53)mEGF with an apparent half-time of 10min; and Des(49–53)mEGF subsequently hydrolyzed to Des(46–53)mEGF with an apparent half-time of 7 h. Native mEGF and its proteolytic fragments have been characterized by 1H-n.m.r. spectroscopy. In the aromatic and aliphatic regions, the 1H-n.m.r. spectrum proved to be a sufficiently sensitive probe for following controlled proteolysis, and for analyzing the influence of the carboxyl-terminal sequence on the hormone conformation and stability.  相似文献   
103.
Summary. The effect of medroxyprogesterone acetate (MPA: Depo-Provera, Upjohn) as a contraceptive agent was assessed in 45 patients with non-metastatic gestational trophoblastic disease and compared with 13 patients using hormonal and 26 patients using non-hormonal methods of contraception. In the whole group of 84 patients 18 (21.4%) required chemotherapy. There was no statistically significant difference in the incidence of persistent trophoblastic disease between MPA (9/45) and the oral contraceptive group (2/13) and MPA and the non-hormonal contraceptive groups (7/26).  相似文献   
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Introduction and Aims. This paper describes the sociodemographic characteristics of 196 psychotic patients admitted to acute psychiatric wards in the UK, Denmark, Germany and Italy, with the aim of comparing comorbid with non‐comorbid patients. Design and Methods. It is a prospective field study with repeated measures at 1, 6 and 12 months. Patients were recruited from acute psychiatric wards in four European centres. They were grouped as comorbid or not on the basis of urine analysis. The Schedules for Clinical Assessment in Neuropsychiatry was used to provide a psychiatric diagnosis, and the Positive and Negative Symptom Severity Scale for further information on specific symptoms with results from the Fragerstrom test for nicotine dependence also reported. Results. Comorbid patients were younger than those who were not but did not differ significantly in the other sociodemographic measures. Differences in sociodemographic characteristics of patients between centres were apparent. Comorbid patients had higher levels of positive and lower levels of negative symptoms than those who were non‐comorbid. Differences were found in the patterns of drug use between comorbid patients who were using cannabis compared with those who were not. Discussion and Conclusions. Cross‐cultural differences in the sociodemographic characteristics of the comorbid patient population give us a better insight into this heterogenous group.[Baldacchino A, Blair H, Scherbaum N, Grosse‐Vehne E, Riglietta M, Tidone L, Criaco C, Marelli MC, Sommer B, Tan L, Little H, Ghodse H. Drugs and Psychosis Project: A multi‐centre European study on comorbidity. Drug Alcohol Rev 2009;28:379–389]  相似文献   
107.
Aim The aim of this study was to explore the predictive value of quantitative assessment of hand movements in 3‐month‐old infants after neonatal stroke. Method Thirteen infants born at term (five females, eight males; mean gestational age 39.4wks, SD 1.19, range 37–41wks; mean birthweight 3240g, SD 203, range 2900–3570g) with neonatal arterial ischaemic cerebral infarction, and 13 healthy infants (mean gestational age 39.1wks, range 37–41wks, SD 1.26; mean birthweight 3190g, SD 259, range 2680–3490g) were enrolled in the study. The absolute frequency and the asymmetry of global hand opening and closing, wrist segmental movements, and independent digit movements were assessed from videotapes recorded at around 12 weeks. Neurological outcome was assessed when the infants were at least 18 months old using Touwen’s neurological examination. Results Five of the 13 infants with neonatal stroke had normal neurological development, and eight had hemiplegia. Asymmetry of wrist segmental movements and the absolute frequency of independent digit movements were significantly different between infants with and without hemiplegia (p=0.006 and p=0.008, respectively). No differences were found in global hand movements. Interpretation We propose that the observed abnormalities of hand movements are the result of two different mechanisms: direct disruption of the corticospinal projection to the spinal cord, and altered modulation of the central pattern generators of general movements.  相似文献   
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Radiofrequency catheter ablation is now the first line treatment for atrioventricular nodal reentrant tachycardia. The success rate is high with a low incidence of complications. However, a possible proarrhythmic effect of radiofrequency energy has been rarely reported and no study has demonstrated a direct correlation between the anatomic site of the radiofrequency application and the origin of a new post‐ablation arrhythmia. We present a case of a focal atrial tachycardia that occurred after slow pathway radiofrequency catheter ablation for atrial nodal reentrant tachycardia and originating close to the previous ablation site. This tachycardia was successfully treated with a second ablation session. (PACE 2011; 34:e33–e37)  相似文献   
110.
LA and PV Anatomy in Patients With AF. Introduction: Although transcatheter atrial fibrillation (AF) ablation requires accurate anatomic knowledge, pulmonary vein (PV) anatomy has not been fully investigated. Aim of this study is to describe left atrium (LA) and PV anatomy by magnetic resonance angiography (MRA) in a large cohort of patients with AF. Methods: MRA was performed in 473 patients preceding transcatheter AF ablation (paroxysmal 60.9%; persistent 39.1%). The Venice Chart classification was used to classify PV branching patterns. Results: About 40% of the patients presented typical PV branching pattern (2 left and 2 right PVs). A representative number of patients presented a common left trunk (19.9% and 11.0% short and long, respectively). A right middle PV was described in 12.5% and 2 right middle PVs in 1.5% patients. The remaining patients presented other complex, previously unclassified patterns: 6.3% presented an accessory PV originating from LA areas not describable as right or “upper” and 8.7% a common left trunk plus right middle PV. Diameters and circumference of each PV, LA, and LA appendage volumes resulted larger in patients presenting persistent compared to paroxysmal AF (P < 0.001). Conclusion: This study highlights that “typical” PV branching pattern is not a common finding. That 25.6% of the patients present at least 1 accessory PV needs to be kept in careful consideration when planning and performing transcatheter AF ablation. In addition, not only LA volume, but also each PV ostia and LA appendage are significantly enlarged in patients with persistent compared to paroxysmal AF. (J Cardiovasc Electrophysiol, Vol. 22, pp. 1‐7, January 2011)  相似文献   
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