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71.
Weaver  DA; Hei  TK; Hukku  B; McRaven  JA; Willey  JC 《Carcinogenesis》1997,18(6):1251-1257
To establish a cell culture model for lung carcinogenesis, independent populations of the human papillomavirus 18-immortalized human bronchial epithelial cell line BEP2D were treated with high linear energy transfer radon-simulated alpha-particles, expanded and xenotransplanted into Nu/Nu mice. Six independent cell lines were established from tumors that developed from three separate radiation treatments as follows: treatment (Tx) 1 (30 cGy--two doses), H2BT, Tx 2 (30 cGy-- single dose), R30T1L, R30T2 and R30T3L, Tx 3 (30 cGy--single dose), H1ATN and H1ATBA1. Cytogenetic analysis revealed common changes in all tumor lines: loss of the Y chromosome (ch), one of three copies of ch8, one of three copies of ch14, and one of two copies of ch4p16-pter and ch11p15-pter. Analysis of polymerase chain reaction-amplified short tandem repeats of informative loci confirmed the loss of chY in all lines and loss of heterozygosity (LOH) at eight loci spanning the length of ch8 in all lines from Tx's 1 and 2. Our data support previous studies indicating the presence of tumor suppressor genes on ch8. LOH also was confirmed on ch14 at locus D14S306 in all cell lines from Tx 2 and in one of two lines from Tx 3. This region, 14q12-q13, may contain changes in one of the five known somatostatin receptor genes (SSTR1). No LOH was detected at any of the informative loci tested for on ch4 or ch11.   相似文献   
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Childhood tuberculosis is perceived by many as a disease of the past. Experience in a children's hospital serving a deprived population suggested that tuberculosis and other mycobacterial infections were not declining in clinical practice. Fifty three tuberculous and 11 atypical mycobacterial infections were identified between 1978 and 1992. There was no decline in tuberculosis and nine of the 11 atypical infections occurred in the last five years. Altogether 40% of cases of tuberculosis were in non-Asian children; 32% had arrived in the UK or visited family overseas in the previous year; and 38% had a history of tuberculosis contact, usually a close adult relative. Nationally, the previous decline in tuberculosis in all ages has reversed. In the local health districts in London's east end, childhood tuberculosis has also stopped declining and seems to be increasing. It is regrettable that BCG vaccination has been abolished by some districts in the UK, against current recommendations. Childhood tuberculosis is still common in the practice described here, including among children who do not fall into conventionally recognised high risk groups. Inner city dwellers and junior doctors are both highly mobile populations, adding to the risk that paediatricians, particularly those in training, may encounter tuberculosis with little or no previous experience of the condition.  相似文献   
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Multisection, dual-echo magnetic resonance (MR) transaxial images of blood vessels contain both anatomic and qualitative information about flow. Even so, the images are produced as a series of two-dimensional tomographic sections from which full visualization of connected structures is difficult. A computer algorithm was developed that automatically detects flowing blood based on pixel intensity and calculated T2 and provides reconstructed views of vessels while analyzing and displaying flow characteristics. Images of abdominal vessels, aortic aneurysms, and the heart were encoded by flow and color to demonstrate depth. In addition, these data were reconstructed to derive a more accurate assessment of patency. With this technique, transaxial images can be used to analyze flow patterns, determine patent areas, and visualize all levels of vessels in a single image.  相似文献   
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OBJECTIVE: To determine whether children's food consumption is increased by the size of the group of children in which they are eating. DESIGN: Crossover study. SETTING: University based preschool. PARTICIPANTS: 54 children, aged 2.5-6.5 years. INTERVENTIONS: Each child ate a standardised snack in a group of three children, and in a group of nine children. MAIN OUTCOME MEASURES: Amount each individual child consumed, in grams. RESULTS: Amount eaten and snack duration were correlated (r = 0.71). The association between group size and amount eaten differed in the short (<11.4 min) versus the long (> or =11.4 min) snacks (p = 0.02 for the interaction between group size and snack duration). During short snacks, there was no effect of group size on amount eaten (16.7 (SD 11) g eaten in small groups vs 15.1 (6.6) g eaten in large groups, p = 0.42). During long snacks, large group size increased the amount eaten (34.5 (16) vs 26.5 (13.8), p = 0.02). The group size effect was partially explained by a shorter latency to begin eating, a faster eating rate and reduced social interaction in larger groups. CONCLUSIONS: Children consumed 30% more food when eating in a group of nine children than when eating in a group of three children during longer snacks. Social facilitation of food consumption operates in preschool-aged children. The group size effect merits consideration in creating eating behaviour interventions.  相似文献   
76.
BACKGROUND/AIMS: Palliative treatment of advanced esophageal carcinoma by esophageal tunnelization with a prosthesis allows immediate relief of dysphagia. However, the procedure is subject to a high rate of morbidity, including gastroesophageal reflux (GER) present in all patients with a prosthesis positioned through the gastroesophageal junction, resulting in complications (pyrosis, aspiration pneumonias, sleep disorders) and reduced quality of life in these patients who already have a lower rate of survival. In an attempt to reduce GER and its complications, the authors created a surgical prosthesis coupled to an anti-reflux valve system, comparing it to the use of an esophageal prosthesis without an anti-reflux valve mechanism. METHODOLOGY: Twenty-two patients were allocated to 2 tunnelization groups: esophageal prosthesis without an anti-reflux valve mechanism (group 1) and surgical prosthesis coupled to an anti-reflux valve system (group 2). The GER was quantified measuring esophageal-gastric pH, and using fluoroscopy, contrast radiographs and esophageal emptying scintigraphy. Initially, the pH of secretions in S1 (esophagus) and S2 (stomach) was determined using reagent strips after aspirating their contents with different syringes. First with the patient seated at rest in bed, later performing a Valsalva maneuver, deep breathing and forced coughing. The same procedure was performed with the patient in left lateral decubitus, right lateral decubitus, and dorsal decubitus with the head of the bed lowered to 20 degrees. After finishing these maneuvers, 15 ml of 1 molar acetic acid were infused through the catheter positioned in the antrum, and, after 5 min, S1 and S2 material sampling was repeated in the same positions as mentioned above. RESULTS: The pH values between the various positions and maneuvers performed in each group separately were not significantly different, but, if we compare the 2 groups, and the secretions obtained in S1 and S2, there was a significant difference in pH measures in all positions. In the patients in group 1, S1 presented a mean pH ranging from 2.87-3.62 in the initial measures, and between 2.17 and 3.5 after the infusion of 15 ml of 1 molar acetic acid. On the other hand, in group 2, the mean pH of S1 remained between 6.34 and 8.32 in the initial measures and between 4.99 and 7.33 in the presence of acid infusion. At the level of S2, the pH remained unchanged between 2 and 2.7, in both groups. CONCLUSIONS: The authors conclude that the association of an esophageal prosthesis with a valve system significantly reduces GER, as compared with its use alone. Furthermore, it allows marked reduction of the symptoms and resulting complications, and does not interfere clinically with esophageal emptying. It thus significantly improves the quality of life of these patients.  相似文献   
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假肿瘤性胰腺炎的CT表现   总被引:8,自引:0,他引:8  
目的 提高对慢性假肿瘤性胰腺炎的影像学特征的认识,材料与方法 回顾性分析12例经临床、病理诊断的假肿瘤性胰腺炎的特点,结果 12例均见胰产质肿块形成,大多为类圆形,直径为2.5~4cm,边缘规则,肿块较均质,如肿块较大,则密度不均,中心坏死,边缘不规则,8例肿块内有钙化,CT增强扫描肿块大多呈明显强化,11例位于胰头部,1例位于胰体部,7例B超呈低回声,5例为不均匀回声,结论 假肿瘤性胰腺炎与胰腺  相似文献   
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