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961.
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Background Objective of the study was to investigate particular clinicopathological features of colorectal signet-ring cell carcinoma.Methods The data of 34 patients with primary colorectal signet-ring cell carcinoma were compared with those of 4,458 consecutive patients with primary non-signet-ring cell colorectal adenocarcinoma between 1978 and 1999. For outcome analysis patients, after curative resection of signet-ring cell cancer, were matched for age, gender, tumour site and stage with patients suffering from poorly differentiated non-signet-ring cell colorectal adenocarcinoma.Results Signet-ring cell carcinoma patients were significantly younger than patients with non-signet-ring cell colorectal adenocarcinoma (median age 60 years vs 64 years, P=0.033). The most common tumour sites were the rectum (47%) and the right hemicolon (29%). They presented with significantly more advanced tumour stages and a significantly higher frequency of distant metastases (44% vs 21%, P=0.002). The rate of curative resections was significantly lower (35% vs 79%, P<0.001). However, the prognosis after curative resection of signet-ring cell cancer was as poor as in poorly differentiated non-signet-ring cell colorectal adenocarcinoma of the same stage (5-year survival rate 46% vs 57%, p=0.935).Conclusions Colorectal signet-ring cell carcinoma is characterized by diagnosis in more advanced tumour stages resulting in lower rates of curative resection. Prognosis is as poor as in non-signet-ring cell colorectal cancer of low differentiation in the same stage.  相似文献   
964.
The use of oral bisphosphonates, particularly members of the aminobisphosphonate subclass, is well established for the treatment of osteoporosis. In a number of clinical settings, intravenous administration appears to be advantageous. However, current dosing and efficacy data are limited while definitive, long-term trials with some of these agents are ongoing. In this article, we review the available information and discuss the use of these drugs on that basis.  相似文献   
965.
A case of pyoderma gangrenosum progressively developing after bilateral mastopexy at the surgical site is described. The described case was successfully treated with corticosteroids, the application of the dermal regeneration template Integra and autologous skin grafts. This approach was able to save the patient's life and to generate a high-quality aesthetical outcome. The article reported the case, reviewed the literature of pyoderma gangrenosum related to mastopexy or augmentation mammoplasty and discussed the use of a dermal regeneration template to optimise aesthetical results after reconstructive surgery.  相似文献   
966.
The MEDLINE database was used to survey the period January 1964 to July 2003 for the number of publications relating to telemedicine (n = 5911), as well as their distribution by country (n = 42). Publications per million inhabitants were then correlated with each country's population density, gross national product, human development index (HDI) and number of PCs per 1000 inhabitants. Telemedicine publications made up 0.05% of all medical publications cited in MEDLINE. American and European countries along with others classified as industrialized produced 97% of all telemedicine publications. In terms of publications per million inhabitants, Norway and Finland took the lead. There were significant correlations between telemedicine publications per capita and HDI (r = -0.60), number of PCs per 1000 inhabitants (r = 0.73) and gross national product per capita (r = 0.69), but not population density (r = -0.12).  相似文献   
967.

Empfehlung des Umweltbundesamtes

Nitrat im TrinkwasserMaßnahmen gem. § 9 TrinkwV 2001 bei Nichteinhaltung von Grenzwerten und Anforderungen für Nitrat und Nitrit im Trinkwasser  相似文献   
968.
A 4-year-old boy was hit by a car travelling at 40 km/h and was admitted 3.5 h later to the department of paediatric surgery. Because he was haemodynamically unstable and needed blood transfusion, the patient underwent an emergency operation. The liver was ruptured in the right lobe. A large haematoma was found in the serosa of the duodenum, along with a Meckel's diverticle, which was left in place. The liver rupture was covered and sealed. One month after the accident the patient was re-admitted, because of abdominal pain and gastrointestinal bleeding. The cause was thought to be the Meckel's diverticle, which was removed later. Two months after the trauma the patient was re-admitted with abdominal pain, again with haematemesis and melaena. The diagnosis of hemobilia was obtained with MRI and angiography, which revealed a ruptured pseudoaneurysm of the ramus dexter of the proper hepatic artery. The patient was successfully treated with embolization. The diagnostic delay was two months, which illustrates the importance of considering the possibility of the diagnosis hemobilia in case of gastrointestinal haemorrhage combined with biliary symptoms.  相似文献   
969.
Bisphenol A induces feminization in Xenopus laevis tadpoles   总被引:6,自引:0,他引:6  
To evaluate possible estrogenic effects of bisphenol A (BPA) in an amphibian model, Xenopus laevis tadpoles were exposed to BPA and 17beta-estradiol (E2) during larval development. After metamorphosis, the gonadal phenotype was determined by gross morphology, and testes were further examined histologically to validate the results. BPA treatment altered the normal sex ratio toward females depending on the BPA concentrations added. Chemical analysis showed a time-dependent decline of BPA during semistatic exposure, indicating that BPA is taken up and metabolized to some extent by tadpoles. In addition, tadpoles were exposed to BPA and E2 for 2 weeks during sensitive stages of sexual differentiation. Afterward, the expression of an estrogenic biomarker, estrogen receptor (ER) mRNA, was assessed by semiquantitative RT-PCR. Both BPA and E2 up-regulated ER mRNA significantly. In conclusion, these results show clear evidence that BPA induces feminization in X. laevis tadpoles, revealing an estrogenic potency of BPA that influences sexual development in amphibians.  相似文献   
970.
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