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41.
Standard imaging techniques using a curved linear array echoendocope are summarized to facilitate the attainment of expertise in endoscopic ultrasonography and endoscopic ultrasound‐guided fine needle aspiration, and to promote the widespread use of this diagnostic and therapeutic tool. Typical images of the mediastinal organs, the bilio‐pancreatic systems and neighboring organs by scanning from the esophagus, stomach, duodenal bulb, and descending portion of the duodenum, are shown in a sequential manner. The basic techniques of endoscopic ultrasound‐guided fine needle aspiration are also presented.  相似文献   
42.
氯胺酮和依托咪酯的BIS50及其对脑电双频指数的影响   总被引:4,自引:0,他引:4  
目的 分别测定氯胺酮和依托咪酯诱导时半数患者入睡时的脑电双频指数(BIS)即BIS50和半数有效量(ED50),比较他们对BIS的影响。方法 选择40例无服用精神药物和镇静催眠药、无术前用药的择期手术患者(ASAⅠ~Ⅱ级),随机分为氯胺酮组(K组,n=20)和依托咪酯组(E组,n=20),以半数效量序贯法分别进行氯胺酮和依托咪酯诱导的睡眠观察,以对语言指令不应和睫毛反射消失为入睡指标,同时记录BIS的变化。对取得的数据以直线回归的方法和加权均数法分别求得氯胺酮、依托咪酯的BIS50和ED50。结果 氯胺酮和依托咪酯诱导后,BIS明显下降(P=0.000983),但两者各自BIS下降幅度在入睡与未睡患者之间没有明显差异(P=0.920501和0.956263)。氯胺酮的BIS50和ED50分别是78.81(95%可信区间67.27~97.10)和0.757mg/kg(95%可信区间0.535~1.071mg/kg),依托咪酯的BIS50和ED50分别是60.00(95%可信区间49.74~76.95)和0.089mg,/kg(95%可信区间0.073~0.107mg/kg)。结论 氯胺酮和依托咪酯皆显著降低BIS,但仅凭BIS难以准确预计是否进入睡眠状态。  相似文献   
43.
The relationship between primary tumor proliferative activity and clinical and pathologic characteristics was analyzed in relation to menopausal status in 32 patients with malignant or benign breast disease. The thymidine labeling index (TLI) showed significantly higher median values in the cancer patients (3.48 per cent) than in the patients with benign diseases (1.02 per cent). TLI was not significantly affected by delayed incubation at room temperature for about 1 hour. In the breast cancer patients, TLI did not significantly correlate to tumor size, the presence of axillary lymph node metastasis or pathologic nuclear grading. The only significant difference was limited to the breast cancer patients without axillary lymph node metastasis in relation to menopausal status; the TLI in the premenopausal patients (5.10 per cent) was significantly higher (p<0.05) than that in the postmenopausal patients (2.28 per cent). These data thus suggest that among premenopausal patients without axillary lymph node metastasis, those with a high TLI could be potential candidates for adjuvant chemotherapy.  相似文献   
44.
Abstract. Objectives. To define risk factors associated with bacteraemia caused by Staphylococcus aureus or coagulase-negative staphylococci; and to use them to define patients in need of empiric anti-staphylococcal antibiotic treatment. Design, Derivation set: observational, prospective study; validation set: retrospective analysis of a prospectively collected database. Setting. Derivation set: Beilinson Medical Centre, Petah Tiqva, Israel—a 900-bed university hospital. Validation set: St Thomas's Hospital, London, UK—an 800-bed teaching hospital. Subjects. All episodes of bacteraemia detected at Beilinson Medical Centre between March 1988 and September 1990 (derivation set, n = 1410), and at St Thomas's Hospital during 1987–1990 (validation set, n = 1040). Interventions. None. Main outcome measures. Percentage of staphylococcal bacteraemia in groups of patients defined by the models. Results. The following factors were associated with Staphylococcus aureus bacteraemia: focus of infection (whether high or low risk), haemodialysis, intravenous drug abuse and infection acquired in the orthopaedic ward. A logistic model was used to divide the derivation set into three groups with percentages of Staphylococcus aureus bacteraemia of 1.8%, 13.2% and 33.7% (P < 0.0001); and the validation group 2.5%, 18.2% and 53.2% (P < 0.0001). Factors associated with coagulase-negative staphylococcal bacteraemia were: central or peripheral intravenous catheter as the focus of infection, a preterm neonate, the presence of a central intravenous catheter, low temperature, and a low white blood cell count. A second model including those factors was used to divide the derivation set into three groups with percentages of coagulase-negative staphylococcal bacteraemia of 1.9%, 22.8%, and 43% (P < 0.0001). In the validation set, the percentages were 2.9%, 22.4% and 31.0% (P < 0.001). Conclusions. The present study defines groups at high risk for staphylococcal bloodstream infection, in which empiric treatment should include an anti-staphylococcal drug.  相似文献   
45.
The aim of this prospective study was to characterize an implant patient population exhibiting clinical signs of peri‐implantitis and to determine subsequently the incidence of progressive attachment loss. The predictive values of diagnostic parameters were evaluated. 25 patients with 54 endosseous implants that had been loaded for 41±15 months were included in the study. Clinical parameters included the assessment of plaque, bleeding on probing, probing depth, attachment levels, and Periotest® values. Probing measurements were performed in duplicate by means of a controlled force electronic probe (Periprobem). Peri‐implant crevicular fluid samples were collected and assayed for neutral proteolytic enzyme (NPE) activity (Periocheck®). Analysis of duplicate baseline probing data revealed a high degree of reproducibility (mean difference: 0.1±0.3mm). A minimum threshold of 1.0mm (>3×S.D.) loss of probing attachment was chosen to classify a site as positive for breakdown. Alternatively, the tolerance method was employed to identify sites with progressive attachment loss. After 6 months, irrespective of the analytical method, 6 percent of all sites (in 19% of the implants) and 28% of the patients had experienced further per attachment loss. There were significant differences ( p <0.05) in mean plaque (73% vs. 45%) and NPE (36% vs. 12%) scores between patients with progressive peri‐implantitis and those with stable peri‐implant conditions. Both bleeding on probing and the NPE‐test were characterized by high negative predictive values, and thus negative scores can serve as indicators for stable peri‐implant conditions. For monitoring peri‐implant health during recall visits, attachment level recordings with a controlled force electronic probe in conjunction with enzymatic diagnostic tests of the host response can be recommended.  相似文献   
46.
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   
47.
实验组为45名缓解的内源性抑郁症患(男25例,女20例)。对照组为15名缓解的双相障碍患者(男8例,女7例),71名正常人(男41例,女30例)。利用作者建立的想象结局法发现:实验组想象力总分显著低于正常人组,特别是当涉及不愉快事件的测题时,单项分亦显著低于正常人。双相障碍组总分亦显著低于正常人。实验组有关性内容的比率得分显著低于正常人。  相似文献   
48.
尼氏小体染色方法的改进及其在神经病理学研究中的应用   总被引:6,自引:0,他引:6  
组织或细胞的染色在病理学诊断、科学研究和教学工作中,都具有非常重要的意义和使用价值。组织切片染色的质量好坏对于医学诊断,科研和教学至关重要。为了更好的研究神经组织,使医学诊断、科研和教学工作更为方便,本文对Toluidine Blue(甲苯胺蓝)染色方法做了一些改进。在传统的甲苯胺蓝染色过程中,仅考虑对细胞核和尼氏小体进行染色,未考虑细胞浆和其他细胞器:而改进后的甲苯胺蓝染色方法在甲苯股蓝染色后用伊红再染色,既考虑对细胞核和尼氏小体进行染色,也对细胞浆进行了染色。结果显示传统的Toluidine Blue染色结果光镜下观察,细胞核和尼氏小体都可见,即尼氏小体为深蓝色,细胞核为蓝色,染色背景为淡蓝色;改进后的染色结果光镜下观察,尼氏小体为紫蓝色,细胞核为蓝色,染色背景为粉红色。可见,改进后的染色方法染出的组织切片比传统的要清晰、美观。随着科学技术的飞速发展,病理学的研究也随之发展,病理技术势必进一步提高,来适应科技的进步和医学的发展。改进的尼氏小体染色法能够使脑组织切片更清楚观察,更有利于医学工作者对神经组织及尼氏小体的研究。  相似文献   
49.
Abstract: Large–scale isolation of islets of Langerhans is one of the major obstacles in islet transplantation. Until now, isolation methods relied on enzymatic digestion, the duration of which relies on a decision dictated by the operator's experience. This approach has always hindered development of an automated method. The aim of this study was to develop a one–step method based on complete digestion of the pancreas. The original aspect of the technique (derived from the Ricordi method) is use of the University of Wisconsin (UW) solution in the digestion medium and a continuous flow collagenase processing circuit with local cooling and rewarming to allow tissue digestion to proceed at 37°C while settling of the cell suspension takes place at 4°C. A stopcock system permits the alternate use of two settling chambers so that while one is in the circuit, the other can be removed for cen–trifugation, resuspension of the crude islet preparation in collagenase in free UW solution, and further purification in a density gradient system. Ten experiments were performed, and 545, 750 ± 48, 670 purified pig islets were obtained per totally digested pancreas. Histological studies showed cell integrity. Insulin secretion in response to double glucose stimulation under perfusion conditions demonstrated the functional viability of the isolated islets. In conclusion, this one–step method makes it possible to obtain a high number of viable islets of Langerhans in the absence of any decision by an operator, and it should therefore provide basis for an automated method.  相似文献   
50.
Prediction of outcome from intensive care after gastroenterologic emergency   总被引:1,自引:0,他引:1  
Prognostic factors determining the outcome from intensive care were studied in 952 patients admitted to 25 Finnish ICUs after gastroenterologic emergency. Logistic regression analysis was used to create predictive models based on the APACHE II–system. The models were constructed by using data from a random two–thirds of the study population and validated in the remaining independent one–third together with the original APACHE II–index. The Acute Physiology Score, age, and a pre–existing liver disease were the three most important determinants of outcome. The inclusion of the TISS score describing the intensity of treatment into a model did not enhance the accuracy of the prediction. Our models were better calibrated than the original APACHE II–equation when tested by the goodness–of–fit –statistics. These statistical models may help the clinicians to predict the outcome for an individual patient by providing them information about the relative impacts of predictive factors or about the probability of death. These probabilities should be interpreted cautiously, taking into acount the limitations of statistical methods. This is especially important when assessing the highrisk patients. Their number in our study was too low for accurate outcome prediction.  相似文献   
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