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921.
Magnetic resonance imaging (MRI) proved to be an important diagnostic tool in the correct staging of bladder neoplasms. The advantage of multiplane imaging and high soft-tissue contrast may be extended by the use of MRI contrast media such as the gadoliniumdiethylene-triaminepentaacetic acid complex. In 60 patients with suspected or proved bladder tumors, the results of preoperative gadolinium-enhanced MRI were correlated with the histopathologic findings. The staging accuracy of infiltrating tumors was 83% and sensitivity and specificity 86% and 83%, respectively. Three tumors could only be localized after administration of gadolinium. All active tumors demonstrated significant contrast enhancement after intravenously injected gadolinium. Small papillary tumors or carcinoma in situ remain problematic to preoperative staging procedures. The advantages of gadolinium-enhanced MRI will best be employed in the exact pretherapeutic staging of infiltrative bladder neoplasms or in restaging procedures after chemotherapy and radiotherapy. 相似文献
922.
923.
Regulation of gene expression by aldosterone in tight epithelia 总被引:2,自引:0,他引:2
F Verrey 《Seminars in Nephrology》1990,10(4):410-420
924.
Oral contraceptive use and invasive cervical cancer 总被引:1,自引:0,他引:1
The relationship between oral contraceptive use and the risk of invasive cervical cancer was investigated using data from a hospital-based case-control study conducted in the greater Milan area, Northern Italy. A total of 367 women under 60 years of age with a histologically confirmed diagnosis of invasive cervical cancer was compared with a group of 323 controls admitted for a spectrum of acute conditions, non-gynaecological, hormonal or neoplastic and apparently unrelated to oral contraceptive use. Cases had used oral contraceptives more frequently than controls, the age-adjusted relative risk (RR) being 1.53 (95% confidence interval 0.99-2.36). The risk increased with duration of use: compared with never users the age-adjusted RR was 1.48 for up to two years and 1.83 for more than two years (chi 2(1) = 5.28, p = 0.02). Allowing for major identified potential confounding factors, including sexual and reproductive habits, by means of multiple logistic regression, did not explain the association (multivariate RR 1.85 for ever use, 1.05 for up to two years and 2.47 for more than two years). When the interaction between oral contraceptive use and parity or sexual habits was analysed, the effects of various factors appeared independent: the point estimate for multiparous oral contraceptive users versus nulliparous never users was 8.01. There was no consistent influence on risk of invasive cervical cancer of age at first use, whereas the RRs were slightly greater for women who had first used oral contraceptives less than ten years before or had last used them less than five years before diagnosis: these findings, however, were far from significant. 相似文献
925.
D J Pearson J P Day V J Suarez-Mendez P F Miller S Owen A Woodcock 《European journal of clinical nutrition》1990,44(4):277-283
Nutritional selenium deficiency disease, due to low soil selenium content, is well recognized in British livestock. The adequacy of the selenium status of 25 healthy human volunteers, 50 blood donors, 94 general medical patients and 106 allergy clinic patients was investigated in 1987/8 by measuring serum selenium concentration and platelet glutathione peroxidase activity. Mean serum selenium concentration for the entire study population was 92 micrograms/l. Significant linear correlations between serum selenium concentration and peroxidase activity indicate that a substantial proportion of both healthy volunteers and medical patients are of low selenium nutritional status. Twenty-five per cent of healthy volunteers and 50 per cent of medical patients had serum selenium values below those required for full expression of selenium-dependent enzyme activity. Deficiency of the antioxidant activities of selenium and selenium-dependent enzymes may be relevant to geographical differences in morbidity from a wide range of human disease states. 相似文献
926.
Renal blood flow, glomerular filtration rate and sodium excretion are known to be affected by adenosine. The present studies were undertaken to investigate the actions of adenosine and its analogs (both agonists and antagonists) on phosphoinositide (PI) hydrolysis in the outer medullary slices. Adenosine was found to cause a dose-dependent stimulation of PI hydrolysis (ED50, 2.8 microM) in renal slices from outer medulla. The adenosine analogs 5'-(N-cyclopropyl)-carboxamidoadenosine (NCCA) and 5'-N-ethylcarboxamidoadenosine (NECA) also stimulated PI hydrolysis in renal medulla. Stimulation of PI hydrolysis was blocked by the adenosine antagonists: aminophylline, 1,3-dipropyl-7-methylxanthine (DMX) and 8-(p-sulfophenyl)-theophylline (8-SPT). Caffeine not only antagonized adenosine-stimulated PI hydrolysis but also increased PI hydrolysis independently. These results indicate that adenosine stimulates PI hydrolysis in renal medulla through a receptor-mediated mechanism. 相似文献
927.
The efficacy of tobramycin in the treatment of ulcerative colitis 总被引:11,自引:4,他引:7
D. A. BURKE A. T. R. AXON S. A. CLAYDEN M. F. DIXON D. JOHNSTON R. W. LACEY 《Alimentary pharmacology & therapeutics》1990,4(2):123-129
This paper reports a double-blind placebo-controlled trial of oral tobramycin in acute ulcerative colitis. Eighty-four patients with an acute relapse of ulcerative colitis were randomized to receive oral tobramycin or placebo for 1 week as an adjunct to steroid therapy. At endpoint, 31 of 42 (74%) in the tobramycin group achieved complete symptomatic remission compared with 18 of 42 (43%) in the placebo group (P = 0.008). The tobramycin group achieved better histological scores (P less than 0.05) at endpoint. These findings show that treatment with oral tobramycin improves the short-term outcome of patients with ulcerative colitis in relapse. 相似文献
928.
929.
With the aim of preventing deep vein thrombosis after radical or modified mastectomy, 100 patients were randomly assigned to one of two different groups: the first group was treated with defibrotide (400 mg b.i.d. e.v.) starting from the day before the operation and continuing for the following seven days. The second group was given calcium heparin (5,000 IU b.i.d. by s.c. route) from day 0 to the 7th post-operative day. Neither side effects nor DVT or PE were observed. The quantity of fluids from the drainages rapidly decreased in both groups from the first day to the third one, while the quantity of blood cells was negligible starting from the second post-operative day. On this basis defibrotide may be considered an effective and well tolerated drug for the prevention of DVT. 相似文献
930.