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91.
The histologic features of prostatic duct-acinar dysplasia have been difficult to analyze ultrastructurally, because of the difficulty in properly selecting and processing such small, randomly situated grossly invisible lesions. We have succeeded in identifying dysplastic foci by examination of the cut surfaces of tissue slices under low magnification. Dysplasia foci were excised from the slices and were compared to adjacent normal tissue by both light and electron microscopy. By electron microscopy (EM), normal secretory cells were filled with myriad tiny clear vacuoles, which were markedly diminished to absent in the cytoplasm of dysplastic cells. Both apocrine and eccrine secretion characterized normal epithelium and were diminished in dysplasia. EM showed striking features of nuclear abnormality more prominently than light microscopy, and qualitative basement membrane abnormalities were revealed. By EM analysis, dysplastic epithelium resembled that of invasive carcinoma more than normal epithelial cells. 相似文献
92.
Stage A versus stage B adenocarcinoma of the prostate: morphological comparison and biological significance 总被引:3,自引:0,他引:3
Morphological features in radical prostatectomy specimens from 11 stage A and 73 stage B prostatic carcinomas were compared by mapping of tumor locations, and determinations of cancer volumes and histological patterns. Small stage A cancers were located anteromedially, while small stage B carcinomas were concentrated against the posterior capsule at the rectal surface. Small stage A carcinomas commonly invaded the anterior fibromuscular stroma and benign prostatic hyperplasia nodules, features that were uncommon even in large stage B tumors. Stage A cancers often appeared to arise within benign prostatic hyperplasia nodules and had a distinctive histological appearance. Even when large, stage A carcinomas tended not to spread close to the rectal surface of the gland. Stages A and B cancers spanned a roughly comparable volume range, and both showed progressive dedifferentiation with increasing volume. It is proposed that stages A and B cancers are biologically similar malignancies, distinguished only by their site of origin. Prognosis for patients with stage A carcinoma probably is closely related to tumor volume and dedifferentiation, features that are not reliably estimated in tissue samples removed at operation for benign prostatic hyperplasia. 相似文献
93.
赵瑛 《中国人民解放军军医大学学报》1995,(2)
Pinealectomyaffectsthediurnalvariationsin2-[~(125)I]iodomelatoninbindingsitesinchickenbursaofFabriciusZhaoYing(赵瑛);PoonAMS,Pa?.. 相似文献
94.
The prevalence of mitral valve pro.lapse in
Chinese was determined by screening 156 heal-
thy subjects and by patholobic examination of
86 adult autopsies. Mitral valve prolapse was
found in 7.7% in the clinical study and 5.8% in
the autopsy study. A slight female preponderance
was noted. 相似文献
95.
vanSonnenberg E; Casola G; Zakko SF; Varney RR; Cox J; Wittich GR; Hofmann AF 《Radiology》1988,169(2):505-509
The authors describe percutaneous treatment of gallbladder or bile duct stones in 18 patients who were poor surgical candidates or in whom conventional therapy failed. Dissolution was performed in most cases with methyl tert-butyl ether (MTBE) because of its potent dissolution properties; other solvents used included monooctanoin or chelating solutions. Gallbladder stones were eliminated in 11 of 13 patients (six of seven with dissolution alone, four of four with dissolution and basket extraction, one with basket removal alone). In five patients with stones in the common bile duct (n = 3), cystic duct remnant (n = 1), and intrahepatic bile ducts (n = 1), stones were eliminated with dissolution alone in two and with dissolution plus basket extraction in one. In two patients percutaneous therapy failed due to complications (vagal hypotension with bile peritonitis and transient respiratory arrest) that occurred during catheter placement. Preliminary results suggest that MTBE is effective for dissolution of many gallbladder stones and some bile duct stones. Noncholesterol solvents and adjuvant mechanical maneuvers are valuable adjuncts to achieve complete stone elimination. 相似文献
96.
Ultrasound imaging and ultrasound guided transrectal core biopsies were performed in 251 consecutive men with abnormal prostates on digital rectal examination. A hypoechoic defect on ultrasound was identified in 227 of 251 patients (90 per cent) corresponding to the area of palpable nodularity or abnormal firmness. A mean of 6.25 biopsies were obtained per patient using a commercially available spring-loaded gun. Biopsies were positive for cancer in 165 of the 251 prostates (66 per cent). Palpable nodules more often were hypoechoic and more often contained cancer than less distinct areas of abnormal firmness on digital examination. Among the clinical stages B1, B2 and B3 nodules 70, 76 and 88 per cent, respectively, were positive for cancer, as were 100 per cent of the clinical stage C prostates. Of 77 abnormally firm, nonnodular prostates 36 per cent were positive for cancer. Random biopsy of the contralateral normal lobe in 56 men with clinical stage B1 or B2 nodules showed cancer present contralaterally in 42 and 60 per cent, respectively; 20 per cent had positive biopsies despite a contralateral isoechoic ultrasound. In 78 patients with prior digitally guided biopsies, ultrasound guided biopsies confirmed previously diagnosed cancers in 94 per cent. However, in 23 of 43 patients (53 per cent) with previous negative digitally guided biopsies, ultrasound guided biopsies made the new diagnosis of cancer. Complications, including post-biopsy fever and bleeding, occurred in 6 of 251 patients (2.4 per cent). The combination of the new spring-loaded biopsy guns and transrectal ultrasound guidance of biopsies provides the urologist with a tool that allows multiple prostate cores to be obtained safely and painlessly, reducing the sampling error and increasing the accuracy in diagnosing prostate cancer in the man with a palpable abnormality of the prostate. 相似文献
97.
Normal anatomy of the prostate and changes in benign prostatic hypertrophy and carcinoma 总被引:2,自引:0,他引:2
J E McNeal 《Seminars in Ultrasound, CT and MRI》1988,9(5):329-334
98.
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