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排序方式: 共有622条查询结果,搜索用时 15 毫秒
1.
Only patients with dysplasia progress to adenocarcinoma in Barrett''s oesophagus. 总被引:12,自引:3,他引:9 下载免费PDF全文
Columnar lined oesophagus (Barrett's oesophagus) carries a risk for the development of adenocarcinoma. Epithelial dysplasia appears to be a precursor but the utility of this marker for predicting subsequent adenocarcinoma is unsettled. We therefore prospectively studied 81 patients with histologically proven columnar epithelium of at least the distal 3 cm of the tubular oesophagus with regular endoscopic biopsies for a total of 289.2 patient years (mean 3.6 years, range 0.5-8). Twenty three patients (28%) had epithelial dysplasia detected during follow up. Both patients with persistent high grade dysplasia present on initial biopsies developed adenocarcinoma after 2.6-4.5 years, despite the absence of gross macroscopic change. The initial single layer pleomorphic high grade dysplasia in one patient regressed to low grade dysplasia which has persisted for 1.5 years. Of 10 patients with initial low grade dysplasia, one progressed to adenocarcinoma in 4.3 years. The low grade dysplasia persisted unchanged in seven patients for 1.5-7 years and appears to have regressed in two patients after three to five years. Ten patients developed low grade dysplasia during the surveillance period. This has persisted unchanged in six patients from 0.5-5 years, regressed in three for 0.5-5 years and has appeared after the first yearly biopsy in one patient. No patient without dysplasia has developed adenocarcinoma. The incidence of adenocarcinoma in Barrett's oesophagus in this study is one case per 96 patient years. This is 61 times (95% confidence limits 12-176) the age adjusted incidence of oesophageal cancer in Australia. Persistent high grade dysplasia appears to be a sensitive indicator for the development of subsequent adenocarcinoma. 相似文献
2.
Predicting cholangiocarcinoma in patients with primary sclerosing cholangitis before transplantation. 下载免费PDF全文
Patients with primary sclerosing cholangitis are at an increased risk of developing cholangiocarcinoma, which is difficult to diagnose because the biliary tree is already distorted. Eleven patients with primary sclerosing cholangitis who underwent orthotopic liver transplantation at this hospital were evaluated. Four patients had coincidental histologically proved cholangiocarcinoma. Patients with cholangiocarcinoma in contrast to patients without tumour presented with rapid onset of persistent jaundice, pruritus, and weight loss associated with an appreciable rise in bilirubin (8x v 2x) and alkaline phosphatase (3.5x v 1.2x) over one year. Cholangiography and computed tomography showed appreciably dilated intrahepatic bile ducts (3/4 v 0/7). The diagnosis of cholangiocarcinoma could only be established before operation in one patient by fine needle aspiration cytology. Tumour was recognised at operation in one other. Histological examination of hepatectomy specimens showed that patients with cholangiocarcinoma had less advanced histological features of primary sclerosing cholangitis. Multiple areas of carcinoembryonic antigen positive epithelial atypia and carcinoma in situ were found in all patients with cholangiocarcinoma. Cholangiocarcinoma recurred in two patients at 14 and 39 months after transplantation. Superimposed cholangiocarcinoma can be predicted in most patients with cholangitis before transplantation, although a definitive diagnosis is difficult to make. Their prognosis after successful transplantation is guarded. 相似文献
3.
Czaja K Kraeling R Klimczuk M Franke-Radowiecka A Sienkiewicz W Lakomy M 《Acta neurobiologiae experimentalis》2002,62(4):227-234
Previous morphological studies revealed that the adipose tissue is innervated by adrenergic nerve fibers. Furthermore, physiological studies showed that the metabolism of adipose tissue is controlled by the adrenergic component of the nervous system. However, nothing is known on the sources of innervation of different fat tissue depots. Therefore, we decided to study the distribution of ganglionic sympathetic neurons innervating adipose tissue in the pig by means of a retrograde tracing method. We used 9 male and 9 female pigs of approximately 50 kg body weight. The retrograde tracer, Fast Blue (FB), was injected into the subcutaneous, perirenal and mesentery fat tissue depots. Results of the present study showed that numerous centers of the sympathetic nervous system innervate adipose tissue in the pig. FB+ neurons projecting to the subcutaneous fat tissue were placed in the thoraco-lumbar region of the sympathetic chain ganglia (SChG). However, neurons supplying perirenal and mesentery fat tissue depots were found in both the SChG and prevertebral ganglia (PVG). We conclude that different adipose tissue depots (subcutaneous, perirenal and mesentery) have different sources of innervation and that there is no significant difference in the distribution of neurons innervating adipose tissue in male and female pigs. 相似文献
4.
Kaczmarek P Respondek-Liberska M Borowski D Wielgoś M Czuba B Oszukowski P 《Ginekologia polska》2007,78(11):861-864
OBJECTIVES: to confirm that fetal echocardiography is indeed possible in late first trimester and that it improves the standard of the so-called "genetic" ultrasound scan. MATERIAL AND METHODS: Early echocardiography was performed in 75 fetuses from high and low risk pregnancies. All fetuses underwent echocardiography examination in 18-22 weeks of gestation and established follow up. RESULTS: The most suitable method of visualization seems to be transabdominal examination, between 13.0-13.6 weeks of gestation, an transvaginal one, between 12.0-12.6 weeks of gestation, with 90% effectiveness. In researched group of 75 fetuses (with established follow up) there were four heart defects (5.3%). Three of them were diagnosed before 14th week of gestation. One case (tetralogy of Fallot) was overlooked. There were two false positive diagnosis verified at 20th week of gestation. CONCLUSIONS: Early echocardiography, especially between 12.0-13.6 weeks of gestation, is a possible and valuable method of diagnosis. Reference evaluation should be performed between 18 and 22 weeks of gestation. In cases with suspected anomalies karyotyping is recommended. Congenital heart disease diagnosed at late first trimester should be treated as the next potential marker of genetic disorder. 相似文献
5.
OBJECTIVES: Ovarian cancers still remain a significant worldwide epidemiological problem. The vast majority of newly diagnosed cases are in advanced clinical stages, and the five-year survival rate in all clinical stages amounts up to less than fifty percent. A better understanding of the biology of ovarian cancer can bring us closer to successful treatment and recovery. The aim of this study was to evaluate the expression of luteinizing hormone (LH)/human chorionic gonadotropin (hCG) receptor (LH/hCGR) and the expression of hCG protein in the ovarian cancer tissue. MATERIALS: Histologically proven primary ovarian cancer samples (n=20) were obtained from women undergoing gynecologic surgery. Frozen sections of ovarian cancer tissues were evaluated by means of indirect immunofluorescence. RESULTS: The expression of hCG protein was ubiquitous throughout all samples, while LH/hCGR was detected in only sixty percent of samples. Co-expression of LH/hCGR and hCG protein was detected in some individual cells in tumor tissue. Some cancer cells expressed only hCG protein, but not LH/hCGR. CONCLUSIONS: Expression of LH/hCG receptor is a characteristic feature of various histological types of ovarian cancer. Co-expression of LH/hCGR and hCG protein in individual cancer cells may point to an autocrine or paracrine mechanism of _hCG activity in the tumor microenvironment. Further studies are needed to evaluate LH/hCGR and hCG protein function in the course of neoplastic development. 相似文献
6.
Marcin Markowski Adam Kaliński Joanna Skwarska Jarosław Wawrzyniak Mirosława Bańbura Janusz Markowski Piotr Zieliński Jerzy Bańbura 《Bulletin of environmental contamination and toxicology》2013,91(3):302-305
The aim of this study was to determine the possibility of using feathers of blue tit nestlings to assess the level of endogenous accumulation of lead. For this purpose we conducted an experiment with lead application to randomly chosen nestlings from eight randomly drawn broods. Five days after the exposure, feathers of lead-treated nestlings had significantly higher lead concentrations than control nestlings. This result suggests that feathers can be used as reliable non-destructive bioindicators to assess the level of heavy metals originating from contaminated food, which is of great significance for comparative studies on ecological consequences of pollution. 相似文献
7.
Anna Zawadzka Iwona Łozińska Zuzanna Molęda Mirosława Panasiewicz Zbigniew Czarnocki 《Journal of pineal research》2013,54(4):435-441
Novel inhibitors of cholinesterases, especially butyrylcholinesterase (BuChE), were obtained by coupling melatonin–tacrine heterodimers via the carbamate bond. Compounds 14a‐i possessed potent cholinesterase inhibitory activity (with IC50 values as low as 1.18 nm for acetylcholinesterase (AChE) and 0.24 nm for butyrylcholinesterase (BuChE)). These heterodimers exhibit selectivity toward BuChE, being from 4‐ to 256‐fold more active toward BuChE than AChE, but still acting as better AChE inhibitors than tacrine 4 . 相似文献
8.
17 serum samples from cats after surgery operations in one of veterinary clinic in Olsztyn have been examined. The study on anti-Toxoplasma gondii immunoglobulin IgG presence was carried out by direct agglutination method using the Toxo-Screen DA test. 70.6% positive samples in 1:40 titration, 58.8% in 1:4000 titration and 5.9% questionable result in both dilutions were obtained. 相似文献
9.
BACKGROUND. Gated single photon emission tomography (SPET) may simultaneously assess perfusion and function of the myocardium. AIM. To evaluate the relationship between the presence of ischaemia during an adenosine stress test and the changes in left ventricular (LV) function obtained after stress and at rest with gated SPET by using adenosine same-day stress and rest protocol. METHODS. The study population consisted of twenty eight patients. The gated SPET acquisition was performed both after adenosine vasodilatation and at rest with a protocol as follows: 300 MBq of Tc-99m Myoview at stress, 700 MBq reinjection at rest and double head gamma camera. Global left ventricular ejection fraction (LVEF) and end-diastolic and end-systolic volumes (EDV, ESV) as well as the regional wall motion reversibility from post-stress and resting scan were analysed. RESULTS. Wall motion disturbances were present in the stress study in 15 patients with subsequent improvement in 14 cases on the rest scans. An independent evaluation of the perfusion data revealed significant reversible myocardial ischaemia in 18 patients and negative result in 10. There was a significant difference between EDV change in patients with or without ischaemia (p<0.02). The post-stress LVEF and ESV were significantly different from those measured at rest. Reversible regional wall motion impairment indicated the presence of significant reversible myocardial ischaemia with an 88% positive predictive value (70% and 75% for sensitivity and specificity, respectively). CONCLUSIONS. The post-stress LVEF with gated SPET may not reflect true resting measurements. The qualitative assessment of regional wall motion reversibility shows better correlation with the ischaemic scan pattern than the difference in the LVEF and may be helpful in assessing the significance of reversible myocardial ischaemia. 相似文献
10.
Sławomira Kyrcz-Krzemień Grzegorz Helbig Mirosław Markiewicz 《Acta haematologica Polonica》2013,44(3):222-226
Acute myeloid leukemia (AML) is a heterogeneous disorder with a diverse prognosis. About 70% of AML patients may achieve complete remission after conventional chemotherapy, but long-term outcome remains unsatisfactory. The development of molecular biology resulted in a better understanding of AML pathogenesis as well as it allowed us the introduction of targeted therapy. However, most AML patients still require the allogeneic hematopoietic stem cell transplantation (alloHSCT) to be cured. The long-term results of alloHSCT for AML depend on a variety of factors including the age at transplant, the presence of well-defined risk factors and disease status at transplant. It seems that the combination of targeted therapy with conventional chemotherapy and subsequent alloHSCT may be a chance for curing a significant proportion of AML patients. 相似文献