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21.
Gastroesophageal reflux disease (GERD) is the most common disease of the upper gastrointestinal tract. With the introduction of proton pump inhibitors medical treatment of GERD has been significantly improved. However, the development of laparoscopic antireflux surgery resulted in an increasing interest of surgeons in this disease. An interactive meeting was organized in order to develop an agreement between gastoenterologists and surgeons regarding therapeutic decisions and this is the main topic of this paper.  相似文献   
22.
Secondary analysis of four surveys was carried out in order to examine the association of physical activity and various aspects of mental health in the household populations of the United States and Canada. Level of physical activity was shown to be positively associated with general well-being, lower levels of anxiety and depression, and positive mood. This relationship is independent of the effects of socioeconomic status and physical health, and described younger and older members of both sexes. The association is particularly strong for women and persons age 40 years and over. The robustness of this conclusion stems from the nature of the data sources: four population samples in two countries over the span of 10 years in which physical activity levels were assessed by four techniques and psychological status was assessed by six distinct scales. Although the surveys are cross-sectional, the most plausible explanation for the results is that physical activity enhances mental health in certain respects. Data on the comparative effects of recreation and housework suggest that quality of time, and not mere energy expenditure, must be taken into account in attempts to explain the psychological benefits of physical activity.  相似文献   
23.
Cystic pancreatic tumors: CT and sonographic assessment   总被引:6,自引:0,他引:6  
Thirty-five CT scans and 23 sonograms of 45 pathologically proved pancreatic cystic neoplasms (16 microcystic adenomas, 17 mucinous [macrocystic] cystadenomas, and 12 mucinous [macrocystic] cystadenocarcinomas) in 43 patients were retrospectively and blindly reviewed. Radiologic findings and their usefulness in differentiating microcystic from mucinous subtypes were assessed. The number of cysts within the tumors (more than six in microcystic adenomas and six or fewer in mucinous cystadenomas and cystadenocarcinomas) and the diameter of the majority of cysts within the tumor (less than or equal to 2 cm in microcystic adenomas and greater than 2 cm in mucinous tumors) were the most helpful radiologic findings in differentiating tumor types. Calcification was present in 38% of microcystic adenomas, 18% of mucinous cystadenomas, and 8% of mucinous cystadenocarcinomas by CT. Calcification was not definitely identified on any of the sonograms. A central scar was identified in only two (13%) of 16 microcystic adenomas. Blind retrospective review was often able to correctly classify tumors as either microcystic (CT, 93%; sonography, 78%) or mucinous (CT, 95%; sonography, 93%). All tumors with a typical appearance on either CT or sonography were categorized correctly. Cystic pancreatic tumors may be difficult to prospectively separate from other types of pancreatic cysts. Assuming a cystic neoplasm is present, it often can be classified correctly as microcystic or mucinous (macrocystic) by using the above criteria.  相似文献   
24.
Autoimmune progesterone dermatitis is a rare condition, characterized by recurrent premenstrual exacerbations of a dermatosis, in which sensitivity to progesterone can be demonstrated. The sensitizing mechanism is unknown. The aim of this study was to test the hypothesis that cross-sensitivity between steroid groups could induce allergy to endogenous progesterone in these patients. 5 patients with autoimmune progesterone dermatitis and 1 with oestrogen-sensitive dermatitis have been patch tested with a corticosteroid series, conjugated oestrogen 1% in petrolatum (pet.), and 17-α-OH-progesterone 2% pet. There were no immediate or delayed reactions at 2 and 4 days to any steroid group. We have therefore been unable to demonstrate steroid cross-sensitivity, or a use for 17-α-OH-progesterone in the investigation of oestrogen - and progesterone-sensitive dermatoses.  相似文献   
25.
Tumor targeting by an aptamer.   总被引:10,自引:0,他引:10  
Aptamers are small oligonucleotides that are selected to bind tightly and specifically to a target molecule. We sought to determine whether aptamers have potential for in vivo delivery of radioisotopes or cytotoxic agents. METHODS: TTA1, an aptamer to the extracellular matrix protein tenascin-C, was prepared in fluorescent and radiolabeled forms. After in vivo administration, uptake and tumor distribution of Rhodamine Red-X-labeled aptamer was studied by fluorescence microscopy. In glioblastoma (U251) and breast cancer (MDA-MB-435) tumor xenografts, biodistribution and imaging studies were performed using TTA1 radiolabeled with (99m)Tc. Tenascin-C levels and tumor uptake were studied in a variety of additional human tumor xenografts. To assess the effect of radiometal chelate on biodistribution, mercapto-acetyl diglycine (MAG(2)) was compared with diethylenetriaminepentaacetic acid and with MAG(2)-3,400-molecular-weight PEG (PEG(3,400)). RESULTS: Intravenous injection of fluorescent aptamer TTA1 produced bright perivascular fluorescence in a xenografted human tumor within 10 min. In the ensuing 3 h, fluorescence diffused throughout the tumor. Labeled with (99m)Tc, TTA1 displayed rapid blood clearance, a half-life of less than 2 min, and rapid tumor penetration: 6% injected dose (%ID)/g at 10 min. Tumor retention was durable, with 2.7 %ID/g at 60 min and a long-lived phase that stabilized at 1 %ID/g. Rapid tumor uptake and blood clearance yielded a tumor-to-blood ratio of 50 within 3 h. Both renal and hepatic clearance pathways were observed. Using the (99m)Tc-labeled aptamer, images of glioblastoma and breast tumors were obtained by planar scintigraphy. Aptamer uptake, seen in several different human tumors, required the presence of the target protein, human tenascin-C. Modification of the MAG(2) radiometal chelator dramatically altered the uptake and clearance patterns. CONCLUSION: TTA1 is taken up by a variety of solid tumors including breast, glioblastoma, lung, and colon. Rapid uptake by tumors and rapid clearance from the blood and other nontarget tissues enables clear tumor imaging. As synthetic molecules, aptamers are readily modified in a site-specific manner. A variety of aptamer conjugates accumulate in tumors, suggesting imaging and potentially therapeutic applications.  相似文献   
26.
A method of assessing facial attractiveness is described in which facial photographs were ranked by adults in order from the most to the least attractive. The rankings of a group of normal 10-year-old children were compared to those given to a group of similarly aged patients with repaired clefts. Most previous methods have grouped patients into categories, but this tends to obscure individual differences in facial attractiveness: patients with small differences in appearance are generally placed in the same group. In the ranking technique described in this paper these individual differences were not obscured. Those individuals with repaired clefts were consistently judged as being less attractive than those in the normal group. It is suggested that this method could be further developed to assess the cosmetic benefit produced by treatment of facial deformity.  相似文献   
27.
Secretion of plasminogen activators and their inhibitors was examined in cultures of human retinal pigment epithelial (RPE) cells. The methods employed were zymography and reverse zymography, solid-phase immunocapture assay, metabolic labeling followed by immunoprecipitation, and immunofluorescence. The results showed that these cells produce urokinase-type plasminogen activator (u-PA) and a plasminogen activator inhibitor (PAI) which is immunologically and biochemically similar to PAI-1. Tissue-type plasminogen activator activity (t-PA) was not detected, but we detected small amounts of t-PA in an inactive complex with inhibitor in RPE cell-conditioned media. We conclude that RPE cells have the potential to utilize u-PA-catalyzed plasminogen activation which is subject to regulation by PAI-1. These results may have a bearing on the pathogenesis of proliferative retinal diseases.  相似文献   
28.
A prospective randomized trial of laparoscopic versus open appendectomy.   总被引:20,自引:0,他引:20  
BACKGROUND. Laparoscopic appendectomy is feasible, but whether it confers any advantage to patients with acute appendicitis is not known. We performed a randomized controlled trial to compare results of laparoscopic and open appendectomy in patients with signs and symptoms suggesting acute appendicitis who were seen by one surgical team. METHODS. Sixty-two consecutive patients were randomized, 30 to laparoscopy and 32 to a classical open appendectomy. Postoperative recovery, complications, and return to normal activities were compared in the two groups. RESULTS. The laparoscopy group were discharged earlier (2.5 vs 3.8 days, p less than 0.01). Postoperative complications were more frequent after open appendectomy. Follow-up showed less pain, shorter bed stay at home, and faster return to work and sport after laparoscopic appendectomy. CONCLUSIONS. This prospective randomized study shows that laparoscopic appendectomy is superior to open appendectomy in terms of hospital stay, postoperative complications, and return to normal activities and is recommended as the approach of choice in the management of acute appendicitis.  相似文献   
29.
30.
INTRODUCTION: Clinical decisions are based on x-ray measures of radiographs. However, the reliability of assessing the angular measurement of fractured femurs in children is unknown. The purpose of this study was to determine the intra- and interrater reliability of an x-ray assessment of femoral shaft fracture angulation in children. METHODS: On 2 occasions, 3 raters evaluated 30 radiographs of children aged 4 to 10 years, 3 to 24 months after a femoral fracture. The radiographs were evaluated by an orthopedic surgeon, an orthopedic fellow and a research assistant, using a standardized methodology. Reliability was assessed with the intraclass correlation coefficient (ICC), an index of concordance that ranges from 01, where > 0.75 indicates excellent concordance. RESULTS: The ICC for the intrarater ranged from 0.75 to 0.97. The interrater reliability ICC for anterior or posterior angulation was 0.91 (95% confidence interval [CI] 0.840.95) and for varus or valgus angulation was 0.90 (95% CI 0.790.95). A change in measurement of more than 5 degrees exceeds the variation in measurement and, therefore, can be attributed to a true shift in fracture position. CONCLUSIONS: With specific standardized protocols, radiographic assessment of femoral fractures is reliable, irrespective of the examiner's level of experience.  相似文献   
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