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991.
Squamous cell carcinoma is an extremely rare primary liver tumour. A 42-year-old man presented at our hospital on 19 February 1986, with pain in the right upper quadrant of the abdomen and general fatigue, and reported an 8 year history of this complaint. Ultrasonography showed four cystic masses in the liver with a maximum diameter of 15 cm, one of which contained a solid component. A computed tomography (CT) scan confirmed a huge, predominantly cystic, mass in the liver with a small solid component and irregular wall. Calcifications were seen in the solid components. On 22 April 1986, a laparotomy was performed but the masses were too large to be removed. During 15 years of follow-up after the laparotomy, there had been no change seen in his abdominal CT scan. He subsequently arrived at our hospital again on 10 July 2001 with loss of appetite and of body weight. A CT scan showed a cyst in the liver of 25 cm in diameter with calcification that had a large solid part invading the liver. A post-mortem pathological dissection showed multiple cysts, the largest of which was 25 cm in diameter. They had large solid parts with calcification invading the liver. There were widespread metastatic lesions. Microscopic examination showed the tumour to be a well differentiated squamous cell carcinoma. To the best of our knowledge, this is the first report of a squamous cell carcinoma arising from 15 multiple non-parasitic hepatic cysts after a 15 year follow-up. Furthermore, 23 years had passed since the patient's symptoms appeared for the first time.  相似文献   
992.
A 60-year-old male with elevated serum AFP levels is reported. Other tumor markers apart from AFP were normal. Serum AFP did not bind to Con A or Lentil-lectin by affinity chromatography. Abdominal ultrasonography, computed tomography and endoscopic retrograded cholangiopancreatography demonstrated a tumor extending from the body to the tail of the pancreas. The tumor was strongly suggested to be an acinar cell carcinoma of the pancreas, based on the histological findings of the resected specimen. The peroxidase-antiperoxidase method showed cancer cells to be positive for AFP. In Japan; only 27 cases of pancreatic cancer with elevated serum AFP level have been reported. This is the first Japanese case of pancreatic cancer in which the binding of serum AFP to lectins was investigated.  相似文献   
993.
994.
Hen ovalbumin (OVA) is known to exist as a singly N-glycosylated form with a glycan chain on Asn-292 in egg white. Previous studies showed that di-N-glycosylated form of OVA [Di-OVA; CHO-Asn-292/CHO-Asn-311 (CHO, N-glycan chain)], which has two N-glycan chains on Asn-292 and Asn-311, was expressed only transiently in hen oviduct. Di-OVA was not found in egg white, suggesting that this form cannot be secreted normally and may possibly be converted to mono-N-glycosylated OVA (CHO-Asn-292/Asp-311) by the action of peptide:N-glycanase (PNGase) during synthesis and secretion. In this study, we have identified the putative PNGase activity in the homogenate of hen oviduct, purified 1,000-fold, and designated as PNGase HO. We examined the reactivity of Di-OVA to PNGase HO and found that this enzyme site-specifically cleaved off the glycan chain at Asn-311 to convert Di-OVA into the mono-N-glycosylated form (CHO-Asn-292/Asp-311). In contrast, this enzyme was found not to act on the mono-N-glycosylated OVA (CHO-Asn-292/Asn-311) found in egg white when it was tested as a substrate. The present findings support our view that de-N-glycosylation catalyzed by PNGase may be involved in quality control of newly synthesized proteins by converting its diglycosylated form into the mono-N-glycosylated form that can be secreted. However, the alternative possibility that de-N-glycosylation may trigger cytosolic degradation of the aberrantly glycosylated glycoprotein cannot be ruled out.  相似文献   
995.
996.
Recently chemoradiotherapy for esophageal cancer has been drawing public attention to the issue of quality of life maintenance for patients. Although the standard method of chemoradiotherapy is CDDP/5FU, it has been claimed that CDGP (a derivative of CDDP) alone is more effective than CDDP for the treatment of esophageal cancer due to its low nephro- and digestive toxicity. We used a small amount of CDGP/5-FU in combination with radiation instead of CDDP, for the treatment of esophageal cancer and performed clinical examination of patients. The partial response rate was 80% and the complete response rate was 50%. Major side-effects were leukopenia, neutropenia, thrombocytopenia and anemia. Further study of dosage and schedule is necessary, however, CDGP/5-FU combined with radiation therapy could be used as choices of chemoradiotherapy for esophageal cancer in the future.  相似文献   
997.
998.
Changes in pituitary mRNA levels of LHbeta-subunit (LHbeta) and glycoprotein hormone alpha-subunit (common alpha) were investigated in male Japanese quail under natural and laboratory conditions to clarify the mechanisms of seasonal regulation of luteinizing hormone (LH) secretion. In Experiment 1, birds were kept in outdoor cages under natural conditions from August for 12 months. Both LHbeta and common alpha mRNA levels decreased rapidly from August to September, and after a period of low levels from October through January, they began to increase in February and continued to increase until July. There were more pronounced seasonal changes in testicular weight and cloacal protrusion width with large decreases from August to September and increases from March to May. In Experiment 2, birds were kept on laboratory conditions and transferred from long to short daylengths at 20 or 9 degrees C and held for 14 days. Although common alpha mRNA levels, plasma LH concentrations, testicular weight, and cloacal protrusion area decreased on short days without low temperatures, levels of LHbeta mRNA did not change. Short daylengths combined with low temperatures induced testicular regression and caused decrease in all the parameters measured. Low temperatures under long days did not induce any change in the parameters significantly. These results suggest that (1) synthesis as well as secretion of LH is regulated seasonally, (2) short daylength does not suppress LH synthesis completely unless combined with low ambient temperature, and (3) the effect of photoperiod on the endocrine system regulating LH secretion is predominant over the effect of ambient temperature but ambient temperature acts as an environmental cue to terminate reproductive activities at late summer to early autumn in Japanese quail.  相似文献   
999.
1000.
We evaluated the incidence and outcome of lung involvement in 35 patients with autoimmune pancreatitis (AIP). Our results indicate that lung involvement is commonly observed in AIP (40%). In addition, corticosteroid treatment improved the lung lesions and appeared to reduce the probability of relapse compared with pancreatic lesions (0% vs 36%). This is the first report to assess the long‐term outcome of lung involvement in AIP (52 ± 33 months).  相似文献   
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