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11.
Coiled bodies and interfascicular threads are conspicuous white matter abnormalities of brains of patients with progressive supranuclear palsy (PSP). Both structures are argyrophilic and immunoreactive for the microtubule-binding protein tau. This report concerns the ultrastructural localization of interfascicular threads and their relationship to coiled bodies in five PSP patients. We showed for the first time that abnormal tubules with a 13- to 15-nm diameter and fuzzy outer contours were the common structures of coiled bodies in the oligodendroglial perikarya and of interfascicular threads. Moreover, the tubules were immunolabeled by anti-tau antibodies. The abnormal tau-positive tubules of interfascicular threads were located in the inner loop of the myelin sheath. Our study further indicated that the thread-like structures in the white matter comprised, at least in part, oligodendroglial processes, and that they were also present in gray matter. We consider that the formation of coiled bodies in the perikarya and of interfascicular threads represents a common cytoskeletal abnormality of the oligodendroglia of PSP patients. Moreover, even though the white matter alterations of PSP resemble those of corticobasal degeneration, there are certain ultrastructural differences in the abnormal oligodendroglial tubules of the two diseases. Received: 4 October 1996 / Accepted: 6 December 1996  相似文献   
12.
To elucidate the effect of jaundice on the electrophysiological characteristics of the gastric mucosa and gastric acid secretion, gastric mucosal potential difference (PD) and gastric acid secretion were measured in rats with obstructive jaundice. Also transepithelial potential difference (TEPD), short circuit current (Isc) and transepithelial electrical resistance (Rt) were measured in the isolated gastric mucosa of rats with obstructive jaundice. Secondly, to confirm whether the alteration of these parameters were induced by jaundice and increased serum bile acids in the jaundiced rats, the effects of biliary drainage on the electrophysiological characteristics and gastric acid secretion, and the effects of bile acid (TCA) on TEPD, Isc, Rt were evaluated. PD, TEPD, Isc and gastric acid secretion were reduced in the jaundiced rats, and tended to recover after biliary drainage. TEPD and Isc were reduced significantly by TCA administration. These results suggest that active ion transport in the gastric mucosal cells and gastric acid secretion are impaired in jaundiced rats and the increased serum bile acid in jaundiced rats may cause these dysfunctions and the impaired active ionic transport function is improved by biliary drainage.  相似文献   
13.
We investigated the effects of energy restriction on the pituitary-ovarian axis and on a hormone responsive gene, the mouse mammary tumor virus (MMTV). Female C3H/SHN F1-hybrid mice, known to display a high incidence of mammary tumors, ate an energy-restricted diet (48 kcal/wk) or a control diet (95 kcal/wk) beginning at the time of weaning. By 67 wk of age, 12 of 32 mice in the control group, but none of the 33 mice in the energy-restricted group, had developed mammary tumors. Six tumor-free mice from each group were studied in detail at 67 wk of age. All six tumor-free control mice, but none of the six energy-restricted mice, showed uterine endometrial hyperplasia at autopsy. Mice subjected to energy restriction did not display an estrous cycle. The average levels of MMTV mRNA in mammary glands and uteri were strongly reduced by energy restriction. MMTV mRNA levels in mammary glands from control mice were two orders of magnitude lower than those in mammary tumors. Energy restriction lowered the percentage of pituitary mammatropes and suppressed proliferation of mammatropes with advancing age. Energy restriction thus appeared to inhibit endometrial hyperplasia and to decrease MMTV production at the mRNA level in the mammary glands and in the uterus. These effects may be a consequence of hormonal changes originating at the pituitary-ovarian axis.  相似文献   
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Summary We describe a giant aneurysm of the anterior communicating artery (ACoA) which was treated with a STA-RA graft-A3 bonnet bypass and A3–A3 side-to-side anastomosis. A giant and partially thrombosed ACoA aneurysm was partially coated 3 years before his current presentation, its gradual increase producing visual field disturbances. An A3–A3 side-to-side anastomosis and STA-RA graft-A3 bonnet bypass were performed. The aneurysm was dissected, and the thrombus removed under transient parent-artery occlusion. The aneurysmal neck was successfully clipped without encountering ischemic changes. This strategy may be useful for treating giant or thrombosed aneurysms in the region of the ACoA.  相似文献   
17.
Endocrine tumor of the pancreas is potentially malignant. A multicenter analysis of these tumors was conducted to clarity the present status of their surgical management and the subsequent long-term surgical results. The Japan pancreatoduodenectomy (JPD) study group carried out the study; 368 patients were enrolled and variables related to tumor characteristics, surgery, and survival were retrospectively analyzed. There were 222 patients with functioning tumor and 143 patients with nonfunctioning tumor. Malignant tumor was found in 140 of 368 (38%) of the patients, and 63/140 (45%) of these patients had metastatic lesion; the most common site of the metastasis was liver 34/136 (25%), followed by regional lymph nodes 26/136 (19%). Pancreatic resection was performed in 91% of patients with nonfunctional tumor and in 83% of those with malignant tumor, and 73% of the pancreatic resections were done with lymph node dissection. The overall 5-year actuarial survival rate was 76% in patients with malignant tumor. The actuarial 5-year survival rate was 93% in the patients without metastasis and 83% in patients who received curative resection. Multivariate analysis showed that the presence or absence of synchronous metastasis was the sole significant prognostic factor. The results suggest that: (i) malignant endocrine tumor of the pancreas is a curable malignancy when pancreatic resection with lymph node dissection is adopted and (ii) that synchronous metastasis is the dominant prognostic factor. This study was carried out as a group project. The authors' institutions are as follows  相似文献   
18.
Two siblings with ileal atresia are described; one boy presented with ileal perforation and the other with meconium peritonitis, diagnosed by antenatal ultrasonography. The site and type of atresia, complications and associated anomalies of reported cases among siblings also are discussed.  相似文献   
19.
Two elderly women complaining of intermittent claudication complicated with persistent sciatic artery are herein reported. A direct femoral arteriogram showed hypoplasty of the superficial femoral artery and an unnatural anatomical relationship between the distal superficial femoral artery and the proximal popliteal artery, thus suggesting the presence of persistent sciatic artery. The diagnosis of persistent sciatic artery was finally made based on the aortography findings including the iliac arterial system and computed tomography (CT) scan. Magnetic resonance imaging (MRI) was helpful to demonstrate the entire image of this anomaly in cases with non-thrombolized sciatic artery. These diagnostic methods were useful in designing the optimal surgical strategy. The first case with a gluteal pulsating mass underwent exclusion of the persistent sciatic artery including the aneurysm through a retroperitoneal approach with a combination of femorotibial bypass, while the second case with thrombosed persistent sciatic artery only underwent femoropopliteal bypass. To recognize such a rare lesion, awareness of the differential diagnosis is important, and to provide appropriate treatment, an accurate whole image including adequate angiography, a CT scan, and magnetic resonance imaging is necessary.  相似文献   
20.
OK-432 is an immunopotentiator which is normally administered by injection. In the present study, the antitumor activity of orally administered OK-432 on various solid tumors and the absorption of OK-432 from the gut were studied. Orally administered OK-432 inhibited the growth of Meth-A and BAMC-1 fibrosarcomas which had been subcutaneously transplanted in BALB/c mice. Autoradiograms of mice which had been administered 14C-labelled OK-432 orally demonstrated the absorption of OK-432 from the gut, and about 6% of orally administered OK-432 was absorbed 24 hrs after its administration. Moreover, an immunofluorescent study using an anti-OK-432 antibody revealed specific fluorescence in the mesenteric lymph node of mice which had been orally administered with OK-432. These results suggest that oral administration of OK-432 may be a beneficial immunotherapy.  相似文献   
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