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Pancreatoblastoma is a rare tumor and has been reported only four times in the cytologic literature, three times in fine-needle aspiration (FNA) biopsy and once in an imprint of resected tumor. We are reporting the fourth case of FNA cytology with immunohistochemical and electron microscopic studies. The patient is a 24-yr-old African American woman, who presented with a pancreatic mass, hepatic masses, and abdominal lymphadenopathy. The aspiration smears of the liver mass showed a biphasic tumor composed of bland-appearing primitive spindled stromal fragments with "spider-web"-like long fibrils interconnecting with sharply angulated islands of cohesive epithelium. At high power, the epithelium is composed of medium-sized cells with round-to-oval vesicular nuclei with fine chromatin and one-to-two small nucleoli. The neuroendocrine component was demonstrated immunohistochemically with synaptophysin and chromogranin expressions. The acinar component and squamoid component were demonstrated ultrastructurally by the presence of 400-600 nm zymogen granules and tonofilaments. The literature was reviewed and the cytological features of all the four cases of pancreatoblastoma are summarized.  相似文献   
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The present study investigated sex differences and the effect of a high level of estradiol in the female meadow vole on performance in the forced swim test (FST) and the Morris water maze in meadow voles. Female meadow voles were ovariectomized (OVX) and administered either vehicle (sesame oil) or estradiol for 2 days prior to performing the FST. Four days following the FST, all animals were run in the Morris water maze. Results indicated that estradiol-injected female meadow voles showed more 'depressive-like' behaviors in the FST (greater time spent immobile and less time spent swimming) than vehicle-treated female or male meadow voles. In addition, estradiol-treated females had impaired performance (greater latencies and distance swam to reach the hidden platform) than both vehicle-treated female and male meadow voles, consistent with previous data. Despite the fact that estradiol administration increased 'depressive-like' behaviors in the FST and impaired performance in the Morris water maze, there was no correlation between the two behaviors indicating that 'depressive-like' behaviors did not account for the differences seen in spatial performance in the Morris water maze. To our knowledge, this is the first demonstration in rodents indicating that estradiol-mediated changes in behavior in the FST is not indicative of subsequent performance in the Morris water maze.  相似文献   
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L1 is a neural cell adhesion molecule mainly involved in axon guidance and neuronal migration during brain development. Mutations in the human L1 gene give rise to a complex clinical picture, with mental retardation, neurologic abnormalities and a variable degree of hydrocephalus. Recently, a transgenic mouse model with a targeted null mutation in the L1 gene was generated. These knockout (KO) mice show hypoplasia of the corticospinal tract. Here we have performed further studies of these KO mice including magnetic resonance imaging of the brain, neuropathological analysis and behavioral testing. The ventricular system was shown to be abnormal with dilatation of the lateral ventricles and the 4th ventricle, and an altered shape of the Sylvius aqueduct. Additionally, the cerebellar vermis of the KO mice is hypoplastic. Their exploratory behavior is characterized by stereotype peripheral circling reminiscent of that of rodents with induced cerebellar lesions.   相似文献   
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To find out the efficacy of sucralfate in preventing gastrointestinal side effects of non-steroidal anti-inflammatory drugs (NSAIDs) a prospective, randomised single blind study was conducted from 1989 to 1992. Patients with osteoarthritis, rheumatoid arthritis and other long standing painful conditions, who were expected to receive NSAIDs for over three months, were recruited into the study. All medicines were discontinued for a period of 10–15 days prior to initial endoscopic assessment. NSAID therapy was started and the patients were randomised to receive either placebo (group A) or sucralfate (group B) in addition. Patient were reassessed clinically every week and an endoscopic examination was repeated after 6–8 weeks of follow-up. A total of 176 patients were studied in group A (n=91) and group B (n=85). At the end of 8 weeks gastrointestinal symptoms were present in 30.6% and 26.4% patients of group A and B respectively. Endoscopic assessment showed superficial lesions in 36.5% and 18.7% while endoscopic ulcer in 2.4% and 1.1% patients of groups A and B respectively. Thus in patients receiving chronic NSAID therapy, simultaneous administration of sucralfate reduces the incidence of superficial gastric lesions but has no significant effect on symptoms or ulcer formation.KEY WORDS: Gastropathy, Sucralfate, Nonsteroidal anti-inflammatory drugs  相似文献   
38.
Rapid slide culture method using human blood medium was utilized for the primary culture of Mycobacterium tuberculosis and the results obtained were compared with results of smear examination of sputum specimens from fresh cases of pulmonary tuberculosis. Smear and rapid slide culture results of a total of 320 patients were analyzed. Slide culture was positive in 104 cases whereas smears were positive in 90 cases. Early culture confirmation in 7 days coupled with positivity better than smear examination, makes rapid slide culture a better method for diagnosis.KEY WORDS: Mycobacterium tuberculosis, Rapid slide culture, Bacteriological techniques, Colony count microbial  相似文献   
39.
The effect of vagotomy on the post-prandial alkaline tide was assessed by measuring the fasting and postprandial urinary pH before and after vagotomy in 50 cases of chronic duodenal ulcer treated by posterior truncal vagotomy or gastrojejunostomy or pyloroplasty. Results showed that post-prandial urinary pH fell after vagotomy confirming the completeness of vagotomy. This test is safe, reliable, noninvasive and a simpler bedside procedure as compared to the conventional Hollander''s insulin test.KEY WORDS: Vagotomy, Alkaline tide  相似文献   
40.
Several studies have reported on the appearance of cutaneous porphyria in people treated with estrogen. This study was undertaken to investigate the effects of oral contraceptives (OCs) on levels of porphyrins in urine in nonporphyric women. 30 women aged 21-40 and on OCs were observed as the study group, and 10 women using other contraceptive methods were observed as the control group. Urinary porphyrins were measured by the Remington method. Levels of urinary coproporphyrin and of urinary uroporphyrin were higher in the study group than in the control group. These differences, however, are not statistically significant. To study the effect of duration of OC treatment, women who had taken OCs for 3-6 months and women who had taken OCs for longer than 6 months were observed, and the means of urinary coproporphyrin and uroporphyrin measured. Again, the differences were found to be insignificant, although slightly higher values of urinary coproporphyrin were obtained for women who had been on OCs for a longer period. These results compare favorably with others reported in the published literature. It can be concluded that OC treatment has no significant bearing on porphyrin metabolism.  相似文献   
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