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91.
Thyroglobulin molecules from normal rats and rats treated with propylthiouracil (PTU) were studied in the electron microscope by the negative staining technique. Intracellular molecules were prepared from exocytotic vesicles and extracellular molecules from the high-speed centrifugation supernatant.In accord with our previous findings, extracellular thyroglobulin molecules from normal glands had an ovoid conformation, whereas extracellular molecules from PTU-treated glands had a different, cylindrical shape. Thyroglobulin molecules from exocytotic vesicles were of the ovoid variety in normal as well as in PTU-exposed thyroids.Two interpretations are discussed. One would be that PTU exerts a non-physiological effect on ovoid molecules in connection with exocytosis of thyroglobulin. The other interpretation is that thyroglobulin molecules normally undergo 2 transformations (ovoid-cylinder-ovoid) during the process of exocytosis; PTU would inhibit the second transformation and cause accumulation of cylinders in the colloid. 相似文献
92.
Masato SHIRAI Edgar JARAMILLO Ragnar BEFRITS Eduard JONAS Tryggve LJUNG Premysl SLEZAK 《Digestive endoscopy》1998,10(3):211-215
Abstract: Vascular ectasia of the upper and lower gastrointestinal tract (GIT) is occasionally seen at diagnostic endoscopy. The therapeutic relevance of these lesions are not always immediately clear. The aim of this study was to review a single institution's experience in the endoscopic diagnosis and treatment of GIT vascular ectasia. In order to identify and determine the characteristics and clinical course of patients with vascular ectasia, records of all adult patients undergoing upper or lower GIT endoscopy between September 1996 and August 1997 were reviewed. During the study period 2547 gastroscopies and 1759 colonoscopies were performed. Eighteen patients (0.7%) were diagnosed with vascular ectasia of the upper GIT and 23 patients (1.6%) the lower GIT. Mean age was 72.7 years and the majority of patients were male. A large percentage of patients had coexisting systemic disease. Anemia without overt GIT bleeding was the presenting clinical sign in 67% of upper GIT and 43% of lower GIT vascular ectasia. Fourteen patients received endoscopic treatment for upper GIT and 18 for lower GIT vascular ectasia. Endoscopic treatment was effective in 12 (86%) and 14 patients (78%) with upper and lower GIT vascular ectasia, respectively. Follow-up ranged from 2 to 12 months. There was only one death in each group, both due to systemic diseases unrelated to vascular ectasia. Vascular ectasia of the GIT is a not infequent cause of upper and lower gastrointestinal bleeding and might be occult. Patients are usually elderly with coexisting systemic disease. Multi-modality endoscopic management is the first line of treatment for this condition and seems both effective and safe. 相似文献
93.
Adjuvant chemotherapy in colorectal cancer: a joint analysis of randomised trials by the Nordic Gastrointestinal Tumour Adjuvant Therapy Group 总被引:1,自引:0,他引:1
Glimelius B Dahl O Cedermark B Jakobsen A Bentzen SM Starkhammar H Grönberg H Hultborn R Albertsson M Påhlman L Tveit KM;Nordic Gastrointestinal Tumour Adjuvant Therapy Group 《Acta oncologica (Stockholm, Sweden)》2005,44(8):904-912
Due to uncertainties regarding clinically meaningful gains from adjuvant chemotherapy after colorectal cancer surgery, several Nordic Groups in the early 1990s initiated randomised trials to prove or reject such gains. This report gives the joint analyses after a minimum 5-year follow-up. Between October 1991 and December 1997, 2 224 patients under 76 years of age with colorectal cancer stages II and III were randomised to surgery alone (n = 1 121) or adjuvant chemotherapy (n = 1 103) which varied between trials (5FU/levamisole for 12 months, n = 444; 5FU/leucovorin for 4-5 months according to either a modified Mayo Clinic schedule (n = 262) or the Nordic schedule (n = 397). Some centres also randomised patients treated with 5FU/leucovorin to±levamisole). A total of 812 patients had colon cancer stage II, 708 colon cancer stage III, 323 rectal cancer stage II and 368 rectal cancer stage III. All analyses were according to intention-to-treat. No statistically significant difference in overall survival, stratified for country or region, could be found in any group of patients according to stage or site. In colon cancer stage III, an absolute difference of 7% (p = 0.15), favouring chemotherapy, was seen. The present analyses corroborate a small but clinically meaningful survival gain from adjuvant chemotherapy in colon cancer stage III, but not in the other presentations. 相似文献
94.
Tone K Omsland Luai Awad Ahmed Anna Grønskag Berit Schei Nina Emaus Arnulf Langhammer Ragnar M Joakimsen Lone Jørgensen Anne Johanne Søgaard Clara G Gjesdal Haakon E Meyer 《Journal of bone and mineral research》2011,26(4):850-856
Higher rates of hip fracture and all fractures combined have been observed in urban compared with rural areas, but whether there are urban‐rural differences in distal forearm fracture rates is less studied. The aim of this longitudinal study was to compare the incidence of forearm fracture in postmenopausal women in urban and rural areas in Norway and to investigate risk factors that could explain potential fracture differences. The study included data from 11,209 women aged 65 years or more who participated in two large health studies, the Tromsø Health Study in 1994–1995 and the Nord‐Trøndelag Health Study in 1995–1997. Forearm bone mineral density (BMD) was measured by single‐energy X‐ray absorptiometry in a subsample of women (n = 7333) at baseline. All women were followed with respect to hospital‐verified forearm fractures (median follow‐up 6.3 years). A total of 9249 and 1960 women lived in areas classified as rural and urban, respectively. Urban women had an increased forearm fracture risk [relative risk (RR) = 1.29, 95% confidence interval (CI) 1.09–1.52] compared with women in rural areas. Rural women had higher body mass index (BMI) than urban women, and the RR was moderately reduced to 1.21 (95% CI 1.02–1.43) after BMI adjustments. Rural women had the highest BMD. In the subgroup with measured BMD, adjustments for BMD changed the urban versus rural RR from 1.21 (95% CI 0.96–1.52) to 1.05 (95% CI 0.83–1.32), suggesting that BMD is an important explanatory factor. In conclusion, higher rates of forearm fractures was found in urban compared with rural women. © 2011 American Society for Bone and Mineral Research. 相似文献
95.
Jonas E Näslund E Freedman J Befrits R Blomqvist L Siösteen AK Jacobsson H Hultcrantz R 《Journal of gastroenterology and hepatology》2006,21(4):674-681
BACKGROUND AND AIM: Primary sclerosing cholangitis is a chronic cholestatic disease characterized by obliterative fibrosis of intrahepatic and/or extrahepatic bile ducts. The unpredictable clinical course of the disease can be relentless, leading to premature death in a large percentage of patients. Prognostic index formulas, the revised Mayo model being the most frequently used, have been developed to predict clinical course and prognosis. The aim of this study was to investigate the potential value of dynamic (99m)Tc-HIDA SPECT in patients with primary sclerosing cholangitis by correlating scintigraphic results with cholangiographic and biochemical findings and prognostic scoring systems used in clinical practice. METHODS: In 18 patients with primary sclerosing cholangitis, segmental parenchymal and bile duct functions were measured using dynamic (99m)Tc-HIDA SPECT. Quantitative scintigraphic results were compared to cholangiographic findings, as graded by a biliary classification system, the Child-Pugh score and revised Mayo prognostic score, as well as the individual biochemical parameters included in the scoring systems. RESULTS: In individual segments, scintigraphic quantitative parameters indicative of bile flow showed a statistically significant correlation with the state of the bile-flow path for the respective segments as assessed by the biliary classification system. The revised Mayo score correlated with the scintigraphic quantitative parameters indicative of parenchymal function and bile flow as calculated for the whole liver. CONCLUSIONS: Dynamic (99m)Tc-HIDA SPECT, capable of assessing different aspects of liver function for the total liver, as well as for individual segments, has potential value in the management of patients with primary sclerosing cholangitis. 相似文献
96.
97.
Microflora changes with norfloxacin and pivmecillinam in women with recurrent urinary tract infection
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Norinder BS Norrby R Palmgren AC Hollenberg S Eriksson U Nord CE 《Antimicrobial agents and chemotherapy》2006,50(4):1528-1530
Similar changes in the periurethral and vaginal microflora were observed in 19 women with recurrent urinary tract infection following treatment with norfloxacin (NOR) or pivmecillinam (PIV). Escherichia coli strains were suppressed by both treatments. Staphylococcus spp. and enterococci colony counts increased following PIV treatment in the periurethral flora but remained stable with NOR. 相似文献
98.
Endotoxin and occupational airway disease 总被引:2,自引:0,他引:2
Rylander R 《Current opinion in allergy and clinical immunology》2006,6(1):62-66
PURPOSE OF REVIEW: This review provides an update on the role of bacterial endotoxin in occupational airway disease, a problem of importance from diagnostic and preventive points of view. RECENT FINDINGS: Data from human inhalation studies have increased our understanding of the cell mechanisms underlying diseases related to endotoxin exposure. In addition, knowledge from molecular genetics may help us to identify individuals at risk. Several investigations have demonstrated that, apart from endotoxin, other microbial cell wall agents are also related to the risk for symptoms of occupational lung diseases, with pathogenic mechanisms different to those caused by endotoxin. Diagnostic methods have progressed from traditional lung function measurements to sampling of indicators of inflammation in the blood, nasal lavage and induced sputum. Investigations of a longitudinal design have provided important findings on the relationship between acute and chronic effects as well as exposures of risk and risk factors among individuals. SUMMARY: Endotoxin, as well as other agents derived from microbes, are important causative agents for occupational respiratory and other diseases, and exposure may occur in a large variety of occupational environments. Recent data from longitudinal studies provide important information on diagnostic and preventive measures. 相似文献
99.
Jörgen Månsson Bertil Marklund Ragnar Hultborn 《Scandinavian journal of primary health care》2013,31(2):83-89
Objective - To describe the diagnostic work-up pattern in primary health care, aiming, with as few diagnostic activities as possible, to identify a number of malignancies among patients presenting with various symptoms, where a malignancy may be a differential diagnosis. Design - Survey of computerised journals. Diagnostic codes (ICD-9 system in primary health care) relating to signs, symptoms or diagnosis were selected where colorectal, pulmonary, breast and prostate malignancies might be differential diagnoses. All diagnostic actions were analysed. Subjects - 6812 patients over 30 years of age from four health centres who were recorded for a total of 14 455 selected diagnostic codes. Results - The diagnostic actions resulted in 1426 X-ray or sonographic investigations, 340 endoscopies, 16 203 haematology, clinical chemistry or microbiology tests and 667 referrals to specialists. Forty-nine malignancies were diagnosed at the primary health care centres, while 10 malignancies were classified as "missed". The frequency of faecal-occult blood tests performed was low while that of ESR and pulmonary X-ray examinations was high. Conclusion - The task for a GP identifying one or two undiagnosed malignancies per year of the four most common types among all the non-neoplastic ailments, and with as little diagnostic activity as possible, is a professional challenge to be scrutinised continuously. 相似文献
100.
Increasing evidence suggests that the risk for sarcoidosis is related to exposure to microbes, particularly molds. Microbial cell wall agents, even in the absence of clinical infection, could cause a late hypersensitivity reaction leading to the formation of granulomas. A few interventions studies using antimicrobial treatment demonstrate improvement in sarcoidosis. It is suggested that diagnostic tools for the presence of microbes are used in patients with sarcoidosis and that antimicrobial treatment is considered in cases resistant to corticosteroids. 相似文献