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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
921.
Excimer laser coronary angioplasty is a new technique for ablation of coronary stenosis, however, the indications for its application are still controversial. We describe two male patients, 60 and 65 years old, who underwent unsuccessful balloon PTCA with a short, concentric and calcified coronary stenosis, although balloon inflation pressure was increased to a maximum in both cases. Excimer laser angioplasty following the failed procedures showed no evidence for tissue ablation angiographically, but a repeat attempt with balloon angioplasty was successful in both cases. Thus, laser angioplasty may be considered as an adjunct technique to balloon angioplasty after a failed PTCA in resistant, non-inflatable lesions. 相似文献
922.
The incidence of malignant tumours in 570 patients with kidney transplants was examined. It was found to be 20-30 times higher than in the average (normal) population. In accordance with the literature, mainly skin cancers were observed, but at variance with these data, the number of lymphoreticular malignancies was small. On the basis of their study, the authors emphasize the oncogenetic effect of immunosuppression. By comparing the conventional (AZA+PRED) and Cyclosporine (CYA+PRED) treatments, they point out that this risk should be taken into consideration even in Cyclosporine therapy which has otherwise a much more favourable effect. 相似文献
923.
924.
In 31 patients with an essential blepharospasm investigations were undertaken with transcranial cortical and cisternal magnetic stimulation of the facial nerve. Cortical stimulation was performed contralaterally, whereas cisternal stimulation was ipsilateral; the latencies and amplitudes of the potentials were determined. However, the extracranial part of the facial nerve was stimulated in the region of the stylomastoid foramen for neuromyography electrically. In most measurements the response potentials in the orbicularis oculi muscle and the levator labii muscle were determined. Cisternal stimulation yielded normal latencies, whereas cortical stimulation showed an increase of latency in some blepharospasm patients. A difference between the orbicularis oculi muscle and the levator labii muscle as known in patients with hemifacial spasm (20) could not be observed. The mean values of all latencies after cortical stimulation were normal. The method of transcranial magnetic stimulation is an important part of the complete investigation of patients with facial hyperkinesias as shown here in blepharospasm patients. 相似文献
925.
B C Elson D M Ikeda I Andersson C Wattsg?rd 《AJR. American journal of roentgenology》1992,158(5):993-995
The mammographic features of fibrosarcoma of the breast, a rare malignant tumor, have not been described. Accordingly, we reviewed the mammograms, pathology reports, and medical records of five women with this tumor. All cases had surgical biopsies and a diagnosis made by histologic evaluation. The age of the patients ranged from 48 to 79 years. Histologically, three of the five fibrosarcomas were thought to have arisen from phyllodes tumor, and four were palpable. On mammograms, the tumors were dense masses with largely indistinct margins, ranging from 1.5 to 7.0 cm in diameter. One contained calcified osseous elements suggesting osseous trabeculae. Although the osseous trabeculae in that tumor strongly suggested sarcoma, most of the tumors had a nonspecific appearance on mammograms. Fibrosarcomas of the breast have a nonspecific mammographic appearance. Surgical biopsy and histologic evaluation are necessary for definitive diagnosis. 相似文献
926.
J F H?nig 《Bulletin du Groupèment international pour la recherche scientifique en stomatologie & odontologie》1992,35(3-4):107-115
Previous studies indicate that HPV type 16 and 18 (HPV) are associated with squamous cell carcinoma of the head and neck. In this investigation we evaluate in our hospital 253 patients with oral squamous cell carcinoma of the tongue not related to tobacco or alcohol with a tumor index of T2 NO MO between 1981 and 1991. From 12 patients we were able to obtain tissue. For detection of human papilloma virus, DNA sequences 6, 11, 16, 18, 31 and 33 in paraffin-embedded human tissue biopsies a non-radioactive in situ hybridization procedure was utilized. Approximately 60% of the carcinoma of the tongue are positive for episomal viral DNA 6, 11, 16 and 18. These results confirms that HPV infection may play a possible role in the multifactorial etiology of carcinogenesis of squamous cell carcinoma of the tongue and probably acting synergistically with other carcinogenesis. 相似文献
927.
H Bell A Bj?rneboe B Eidsvoll K R Norum N Raknerud K Try Y Thomassen C A Drevon 《Alcohol and alcoholism (Oxford, Oxfordshire)》1992,27(1):39-46
The concentration of alpha-tocopherol was measured in liver biopsy specimens obtained from 83 patients with alcoholic and non-alcoholic liver diseases. The mean hepatic vitamin E content (as alpha-tocopherol) was significantly lower in 23 patients with alcoholic cirrhosis (17.6 +/- 12.1 nmol/mg wet weight liver), compared with 12 patients with normal liver histology (39.2 +/- 29.7 nmol/mg, P less than 0.01). The mean serum concentration of alpha-tocopherol was lower in patients with alcoholic cirrhosis (13.9 +/- 7.0 mumol/l) than in individuals with alcoholic fatty liver (21.3 +/- 9.3 mumol/l, P less than 0.01) and patients with normal liver histology (23.4 +/- 11.6 mumol/l, P less than 0.01). A decreased ratio of serum alpha-tocopherol/total serum lipids was also observed in patients with alcoholic cirrhosis, compared with patients with normal liver histology (P less than 0.05). There was a significant correlation between concentrations of alpha-tocopherol in liver and serum (r = 0.43, P less than 0.001). Furthermore, serum alpha-tocopherol correlated with retinol (r = 0.53, P less than 0.001), selenium (r = 0.45, P less than 0.001), and albumin (r = 0.37, P less than 0.001) in serum. We suggest that the reduced content of hepatic alpha-tocopherol observed in some patients may play a role in ethanol-induced lipid peroxidation. 相似文献
928.
E Kvist K E Sj?lin H Laursen T F Orntoft M A Sturmer 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》1992,100(7):650-654
In a retrospective study of 28 women and eight men with squamous cell metaplasia in different parts of the bladder, including the trigone, no histopathological differences were observed among the regions. All the five (female) patients with parakeratosis had a concomitant invasive bladder tumour. Thirty-eight% of all the patients had a simultaneous neoplastic tumour. The metaplastic lesions were investigated for keratin in 13 patients, and all were positive. In seven out of eight patients, the urothelium adjacent to the squamous cell metaplasia was also positive for keratin, indicating a direct transformation of the urothelium to squamous cell epithelium. The metaplastic cells were investigated for oestrogen receptors in five men and five women, and all were negative, suggesting no relationship between estrogens and squamous cell metaplasia of the bladder. Squamous cell metaplasia in the bladder is not considered a premalignant condition. However, metaplasia and neoplastic tumours are often associated with chronic tissue damage, and the presence of metaplasia may give a warning of conditions that can also cause cancer. 相似文献
929.
F J Skj?rten S H Brorson B Roald E H Str?m B Lund 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》1992,100(11):1001-1007
Fifty renal biopsies were studied by immunoelectron microscopy after embedding in a partly hydrophilic polyacrylic resin (LR White). Immunofluorescence studies were carried out on frozen sections of parallel tissue samples. Polyacrylic embedding gave good preservation of the renal ultrastructure and precise localization of immunoglobulin and C3c antibodies within glomerular electron-dense deposits. Non-specific staining of plasma proteins within vascular lumina could easily be detected. There was good correlation between immunoelectron and immunofluorescence microscopy. Immunoelectron microscopy is a very sensitive method, which can detect small amounts of antigen. More cases were, however, positive by immunofluorescence than by immunoelectron microscopy. This discrepancy may be explained by difference in sample size, and by difference in resolution of morphological details (electron microscopy versus fluorescence microscopy). 相似文献
930.
L Goedel-Meinen M Hofmann G Schmidt W Maier-Rudolph P Barthel A Schrag W Baedeker H Bl?mer 《Zeitschrift für Kardiologie》1991,80(3):187-193
This prospective study examined the influence of long-term amiodarone therapy on the parameters of the signal-averaged ECG and their relation to simultaneously derived Holter monitoring data. For this purpose, 23 patients with angiographically confirmed dilated cardiomyopathy or coronary heart disease and high-grade ventricular arrhythmias, in whom an average of four class I antiarrhythmic drugs had proven ineffective, were stabilized on amiodarone. Before the beginning of therapy, as well as after 2 months and, subsequently, every 3 months, a resting ECG, a signal-averaged ECG by Simson's method, and Holter monitoring were performed. Compared to the initial measurement, we found a significant increase in the duration of the total filtered QRS complex from an average of 114 +/- 24 ms to 127 +/- 35 ms, while the change in voltage did not reach the significance level. The incidence of late potentials remained largely constant under amiodarone; 10 patients showed a constant late potential, 12 patients had no late potential, and one patient with coronary heart disease developed a new late potential. In the long-term follow-up, we ascertained a relatively high responder rate under amiodarone between 41% and 81%. No relation could be detected between the results of the signal-averaged ECG and those of 24-h Holter monitoring. 相似文献