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991.
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Using traditional anatomical and histological methods, the muscle envelope of the pharynx-esophagus junction was investigated in humans and dogs. In the upper (cranial) portion of the esophagus of man and dogs, an inferior anatomical sphincter was detected which histologically can be referred to the group of rhabdo-sphincters. The upper esophageal sphincter is a purely esophageal structure which in man is located at a distance of 25-30 cm from the maxillary incisors. In adult humans, it is 25-30 mm long and is situated obliquely to the long esophageal axis. The posterior semicircle of the sphincter is located higher than the anterior one. In the area of the upper esophageal sphincter the esophageal wall is of different thickness. Due to the muscle envelope and submucous membrane of the base, the right wall is 1.7-2.0 times thicker than the left, anterior or posterior wall. The data obtained from fiber esophagoscopy of patients and electromyography of the pharynx-esophagus junction of dogs have shown that the upper (cranial) esophageal sphincter control food passage from the pharynx to the esophagus and prevents food reflux to the laryngopharynx, protecting airways from aspiration. 相似文献
995.
M F?rkkil? 《Scandinavian journal of work, environment & health》1987,13(4):367-369
Methods for assessing neurological disturbances in the diagnosis of the hand-arm vibration syndrome are described. The clinical examination should comprise a careful history of symptoms and vibration exposure and a consideration of neurological signs known to be associated with vibration exposure. There is as yet no etiologic diagnostic method for vibration-induced neurological lesions. The best method is a relevant clinical examination as described, in combination with a quantitative assessment of sensory modalities (such as the vibration perception threshold) and an electroneuromyographic test. 相似文献
996.
Coronary revascularization using percutaneous coronary intervention (PCI) has rapidly developed in the past 2 decades and its technical and pharmaceutical improvements may avoid bypass surgery in many situations. The use of drug-eluting stents (DES) challenges the classic indications for bypass surgery and shifts them toward PCI, with the need for a critical appreciation of procedure- and patient-related risks. Furthermore, invasive measures such as intravascular ultrasound or pressure wire allow lesion-specific and immediate therapeutic decisions. This overview summarizes the actual potential of coronary intervention. To be aware of potentials and limitations may help the non-interventionalist to advise his patient and to choose the appropriate treatment. 相似文献
997.
998.
R Malmi K O S?derstr?m 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》1991,99(3):233-243
Histological tissue sections of human testicular embryonal carcinoma from 13 patients and of a xenograft tumour in nude mice, as well as cell lines of human embryonal carcinoma, were investigated with eight different lectins to characterize the distribution of glycoconjugates in embryonal carcinoma. In all cases the malignant cells showed binding with Con A, WGA and RCA I conjugates, whereas other lectins were bound to some, but never to all, tumour cells in each group, revealing the heterogeneity of the malignant cells. A polarization of cancer cells was shown particularly with WGA and RCA I labelling, which was most intense on the luminal borders of the carcinoma cells, where pseudotubular structures were formed. The sugar staining properties were retained in cell culture and in the xenograft tumour. Regardless of the germ cell origin, embryonal carcinoma cells differed from normal germ cells. The distribution of glycoconjugates was also different from that of testicular carcinoma-in-situ germ cells, which share morphological features and the pattern of glycosylation with seminoma cells. However, the similarities in lectin binding pattern of seminomas and embryonal carcinomas suggest the close relationship between the two types of testicular malignancy, without excluding the possibility that embryonal carcinomas were derived from seminomas. Although lectins seem to be less important for differential diagnostic use in testicular cancer, our findings showed the usefulness of lectin histochemistry for characterization of embryonal carcinoma. 相似文献
999.
1000.
P J?ppinen T Hakulinen E Pukkala S Tola K Kurppa 《Scandinavian journal of work, environment & health》1987,13(3):197-202
The cancer incidence of 3,545 workers in the Finnish pulp and paper industry was assessed in a retrospective cohort study. The cohort included workers with continuous employment of at least one year between 1 January 1945 and 31 December 1961 and was followed until 31 December 1980. Six subcohorts were formed (sulfite mill, sulfate mill, paper mill, board mill, maintenance department, and power plant). Separate analyses were made for the 2,597 workers hired after 1 January 1945. The smoking habits were surveyed. Among the men, 196 cases of primary cancer were detected versus 203.8 expected [standardized incidence ratio (SIR) 96, 95% confidence interval (95% CI) 82-114], and there were 47 cancer cases among the women versus 57.9 expected (SIR 91, 95% CI 60-108). Lung cancer occurred in 78 men (62.6 expected, SIR 125, 95% CI 98-155), and the excess was the most prominent for the male board mill workers (40 observed, 81.1 expected, SIR 222, 95% CI 158-302), particularly after 20 year's latency (25 observed, 7.8 expected, SIR 323, 95% CI 209-476). Analogous excesses of lung cancer occurred among the men (especially the male board mill workers) who began work after 1 January 1945. The findings were not explained by smoking habits. 相似文献