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81.
Electrically conducting soluble polyaniline (PANI), containing different amounts of a bulky lipophilic cationic additive, tridodecylmethylammonium chloride (TDMACl), was studied by Raman (λexc=780 nm) and UV–vis spectroscopy. PANI was made simultaneously electrically conducting and soluble with bis[4-(1,1,3,3-tetramethylbutyl)phenyl]phosphoric acid in dichloromethane. The PANI membranes were prepared by drop casting on glassy carbon or ITO substrates. Raman and UV–vis measurements were carried out in a 0.1 M CaCl2 solution at potentials between 400 and ?600 mV (vs. SCE) at pH 6, or alternatively at the open circuit potential at pH 10. The results of Raman, UV–vis and cyclic voltammetric measurements confirm that the incorporation of TDMACl into the PANI membrane facilitates the oxidation and reduction of PANI.  相似文献   
82.
报告股骨干骨折切开复位内固定术后不愈合27例。其中,17例钢板固定者,只4例符合要求,9例髓内针固定者,有5例针短小。尚伴有固定方法,钢板或髓内针断裂,以及感染等方面原因有。本组再手术26例1次手术治愈,1例2次手术治愈。绝大部分经带蒂骨皮质剥离^[1]和坚强内固定术后而愈合,不需植骨。产生骨折不愈合的诸因素中,以忽视内固定的基本原则与术中操作不当为主。  相似文献   
83.
应用2%复方去氧胆酸钠、2%复方偏磷酸钠及Ⅰ号或Ⅱ号复方桔皮油乳剂等溶石剂经胆道引流管灌注治疗87例胆道残石病例。治疗前经 X 线或胆道镜确诊。残石部位:肝外胆管31例;肝内胆管37例;肝内外胆管19例。治疗中从引流瓶及大便淘洗中发现大量胆石碎片,经化学分析及电镜检查,与体外溶石试验结果一致。治疗结果:56例全溶,占64.37%;19例残石变小或变少,占21.24%;4例因肝内胆管病变中转手术,占4.86%;8例因治疗反应停止溶石,占9.20%。4例肿大的肝脾缩小,脸色由灰暗变为红润。对改善溶石治疗的有关措施进行了讨论。  相似文献   
84.
Three hundred and thirteen paediatric day case patients were prospectively audited to assess postoperative pain, nausea and vomiting using data sheets completed by nursing staff, anaesthetists and parents. The incidence of nausea and vomiting was 7.3% and was commoner in older children and those who had received opioids. Forty per cent of patients had some degree of postoperative pain; 17% of these patients were scored as having severe pain. Of children who had pain on returning home (31.4%), 85% of these required paracetamol. Fifteen per cent of children had a disturbed night due to pain and/or vomiting after their operation and 28.5% of children had pain on the following day. Boys undergoing circumcision were responsible for a disproportionately high percentage of the severe pain scores. Audit has helped to highlight deficiencies in the service provided and has led staff to try and improve their methods of analgesia.  相似文献   
85.
The aim of the present study is to evaluate drawbacks and advantagesof the choice of hospital versus population controls in a casecontrol study on diet and cancer through the analysis of a retrospectivestudy on diet and gastric cancer (GC) conducted in Forli, Italy,involving 232 cases, 430 population controls and 252 hospitalizedcontrols. The present paper reports the comparison of resultson diet and GC risk obtained using the 2 types of controls.Population controls tended, in general, to eat all kinds offoods slightly more frequently (bread, pasta, cold cuts, freshfish, seasoned cheeses, legumes, garlic, onions and preservedfruits), with the exception of cooked vegetables, which werereported less frequently by population than by hospital controls.ORs for specific foods adjusted for confounders and other foodswere consistent in the separate models including populationand hospital controls respectively for all food groups, withthe exception of cooked vegetables which represented a protectivefactor only when hospital controls were considered (high consumers,population controls: adjusted, OR=0.9, trend p value 0.54; highconsumers, hospital controls, adjusted OR=0.5, trend p value<0.01). Hospital controls were slightly less often currentsmokers (22.6 versus 30.0%) and more often regular wine drinkers(57.5 versus 47.8%) compared with population controls, but noneof these variables was associated with GC risk. The main resultsin this study were consistent using both types of controls,nevertheless the distribution of some dietary variables notrelated to the disease under study differed between the 2 controlgroups, suggesting some caution in the use of hospital controlswhen studying diseases other than GC.  相似文献   
86.
AIMS: Overweight is common during late puberty in female patients with Type 1 diabetes. The aim of this study was to examine the change in body composition from late puberty to early adulthood in such female patients in comparison with age-matched control subjects. METHODS: Eighteen females with Type 1 diabetes and 19 healthy female control subjects were recruited for a case-control study at the age of 16-19 years (baseline). Six years later, 16 of the diabetic females and 17 of the control subjects were re-examined (follow-up). Body composition was assessed by dual energy X-ray absorptiometry. RESULTS: Body mass index (BMI) and fat mass index (total fat mass/height2) were significantly higher at baseline in the diabetic patients than in the control subjects (26.4 +/- 2.6 vs. 23.9 +/- 3.7 kg/m2, P < 0.05, and 10.0 +/- 2.4 vs. 8.0 +/- 2.8 kg/m2, P = 0.04, respectively). At follow-up, these parameters still tended to be higher in the diabetic group (27.8 +/- 4.9 vs. 24.6 +/- 5.7 kg/m2, P = 0.09, and 11.8 +/- 5.6 vs. 8.7 +/- 4.9 kg/m2, P = 0.05, respectively). BMI at baseline was strongly correlated to BMI at follow-up in both diabetic patients (r = 0.60; P < 0.05) and control subjects (r = 0.83; P < 0.01). CONCLUSIONS: Increased fat mass in pubertal girls with Type 1 diabetes seems to persist in young adulthood. This study emphasizes the need for new strategies to prevent the development of overweight during puberty in diabetic girls.  相似文献   
87.
This study presents a unique observational approach to basketball, based on the theory of psychological performance crisis in competition. The approach used takes into account the responses of a player's actions to significant social factors such as team-mates, spectators, the coach and the referees. The contribution of this approach beyond traditional observational techniques is discussed. In our investigation, a single case design was used, in which a professional basketball player was observed during 10 home and 3 away games of the regular season. The relations between the observations and the crisis concept are discussed in detail. In addition, some relevant methodological and applied aspects are presented.  相似文献   
88.
We investigated the role of metabolism in muscle fatigue during voluntary exercise in persons with mild multiple sclerosis (MS). Six MS and 8 healthy control subjects performed intermittent, progressive, isometric contractions of the ankle dorsiflexors, during which we measured maximum voluntary force (MVC), inorganic phosphate (Pi), phosphocreatine (PCr), and pH. During exercise. MVC fell sooner in MS, but by the end of exercise the relative decrease in MVC was similar in both groups. In contrast, at the end of exercise Pi/PCr increased to 1.86 ± 0.22 in controls but to only 0.66 ± 0.04 in MS (P < 0.01); likewise, pH was 6.75±0.04 in controls and unchanged (7.06 ± 0.04) in MS (P <0.01). The smaller metabolic change at the same relative exercise intensity suggests a failure of muscle activation that is present even in mild MS. Neurophsyiologic measures of activation indicated some central activation failure and no neuromuscular junction impairment in MS, and suggested that activation failure beyond the muscle membrane(excitation–contraction coupling) may be important in MS. We conclude that metabolic factors do not play a significant role in the development of muscle fatigue during voluntary exercise in mild MS. © 1994 John Wiley & Sons, Inc.  相似文献   
89.
应用ATL-ultramark超6型彩色多普勒超声诊断仪诊断扩张型心肌病100例,并与性别、年龄相应的正常人对比分析。结果:除扩张型心肌病各组室间隔及左室后壁舒张期厚度与相应正常对照组相比无显著性差异(P>0.05)外,其左室舒张内径及收缩内径、左房内径明显大于正常对照组(P<0.01),左室射血分数及左室内径缩短分数较正常对照组明显降低(P<0.01),并见心腔内血流速度缓慢,颜色变淡。另在77例病人中探及40例瓣膜返流。提示该诊断方法对扩张型心肌病具有直观、简便、准确、迅速的优点,为本病的诊断及鉴别诊断提供了良好的手段。  相似文献   
90.
本文比较了11例眼球异物CT与X线影像,并经手术摘出异物证实,CT眼球异物检出及定位准确性均优于X线,尤其对球壁异物的定位,而且能显示断层眼球壁轮廓,具有直观效果,CT异物影像比异物明显扩大,应警惕CT伪影可能使球壁异物定位发生误差,CT目前尚不能完全取代眼球异物常规X线检查。  相似文献   
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