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1.
Transcapillary fluid balance consequences of missing initial lymphatics studied in a mouse model of primary lymphoedema 总被引:1,自引:0,他引:1
Tine V. Karlsen Marika J. Karkkainen Kari Alitalo Helge Wiig 《The Journal of physiology》2006,574(2):583-596
To investigate the phenotypic consequences of a deranged lymphangiogenesis in relation to tissue fluid accumulation and the possible role of inflammation in the pathogenesis of lymphoedema, we measured determinants of transcapillary fluid filtration and inflammatory mediators in the interstitial fluid in genetically engineered Chy mice, a model for primary congenital lymphoedema (Milroy's disease). Although initial lymphatics were not present in dermis in any of the areas studied (fore paw, hind paw, thigh and back skin) interstitial fluid pressure ( P if ), measured with micropipettes, and tissue fluid volumes were significantly increased only in the areas with visible swelling – the fore and hind paw, whereas interstitial colloid osmotic pressure (COPif ) was increased in all the skin areas examined. A volume load of 15% of body weight resulted in a more pronounced increase in P if as well as a four-fold increase in interstitial fluid volume in Chy relative to wild-type (wt) mice, showing the quantitative importance of lymphatics for fluid homeostasis during acute perturbations. A similar level of proinflammatory markers in interstitial fluid in early established lymphoedema (3–4 months) in Chy and wt suggests that inflammation does not have a major pathogenetic role for the development of lymphoedema, whereas a reduced level of the immunomodulatory cytokine interleukin (IL)-4 may result in a reduced immunological defence ability and thus lead to the increase in inflammatory cytokines IL-2 and IL-6 observed at a later stage (11–13 months). Our data suggest that primary lymphoedema results in a high interstitial fluid protein concentration that does not induce an interstitial inflammatory reaction per se , and furthermore shows the paramount importance of the initial lymphatics in tissue fluid homeostasis, especially during perturbations of transcapillary fluid balance. 相似文献
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Short-Ti inversion-recovery pulse sequence: analysis and initial experience in cancer imaging 总被引:2,自引:0,他引:2
Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy. 相似文献
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Sixteen cases of histopathologically proved solitary rectal ulcer syndrome were encountered. Fifteen patients underwent barium enema study; in nine cases the findings--including rectal stricture, granularity of the mucosa, and thickened rectal folds-were nonspecific. In six cases the study was normal. All patients had a long history of defecation disorders, and defecography was performed in all. In seven cases, intussusception of the rectal wall was seen; in another case the intussusception was accompanied by a rectocele. One case showed rectal prolapse. In four cases, failed relaxation of the puborectalis occurred and prevented the passage of the bolus; in another case there was abnormal perineal descent. In two patients studies were normal. In patients with defecation disorders, the possibility of this syndrome should be considered. Defecography is the method of choice for establishing the diagnosis. 相似文献
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Hans Rostad Anne Naalsund Randi Jacobsen Trond Eirik Strand Helge Scott Erik Heyerdahl Str?m Jarle Norstein 《European journal of cardio-thoracic surgery》2004,26(4):782-786
OBJECTIVE: The final outcome of patients with small cell lung cancer (SCLC) is poor with an overall 5-year survival rate of less than 10%. Therefore, the question of surgery in patients with a technically-operable solitary tumor has been raised. The purpose of this study was to identify the proportion of patients with operable SCLC and to assess the prognosis of different treatment strategies. For patients who were operated, we compared the resection specimens from patients with more than 5-year survival with those with shorter survival to see whether the specimens belonged to different subclasses of SCLC. METHODS: In Norway all clinical and pathologic departments submit reports on cancer patients to the Cancer Registry. The Registry also has a law-regulated authority to collect supplemental information regarding diagnosis, treatment and outcome for all cancer patients from the hospitals in charge. All reports on patients diagnosed as having SCLC in limited disease or unknown stage during the time interval 1993-1999 were reviewed. Patients with a T2-tumor, in whom a pneumonectomy would have to be performed, were classified as potentially operable. Five-year relative survival was calculated for patients diagnosed in 1993-1997. RESULTS: During the actual period 2442 individuals with SCLC were identified. The majority was treated with conventional chemotherapy or concurrent chemoradiotherapy while 38 underwent surgical therapy. Following reclassification of 697 patients reported to have limited disease or unknown stage 180 were judged to be in stage I. In addition to the 38 resected patients 14 were considered fit for surgery technically and medically while 97 were found to be potentially operable treatment modalities apart from surgery yielded a 5-year survival rate <7%. For stage I (N=96) the rate was 11.3% in conventionally treated patients compared to 44.9% for those who underwent surgical resection. By pathological review of surgical specimens a diagnosis of SCLC was confirmed in all patients treated by surgery in the groups with long and short survival. CONCLUSION: This investigation demonstrates that patients with SCLC having a peripherally located tumor should be referred to surgery, as long time survival is far better than for conventionally treated patients. 相似文献