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151.
Eiji Takeuchi Yuji Nimura Shin-ichi Mizuno Hideaki Suzuki Shinsuke Iyomasa Masaki Terasaki Hiroshi Kuriki Keiko Tamiya-Koizumi Shonen Yoshida 《Journal of Hepato-Biliary-Pancreatic Surgery》1997,4(3):254-262
Hepatocyte regeneration has been widely investigated, with the mitotic index and the incorporation of [3H]thymidine being used as regeneration markers. We focused on the induction of DNA replication enzymes, particularly DNA polymerases
(pol) α, δ, and ε. Using rat models, we have shown that the activity of pol α in crude liver extract well represents the regenerating
capacity of hepatocytes. Using pol α as an indicator, we analyzed liver regeneration in rat models under various conditions:
obstructive jaundice, external or internal biliary drainage, and the obstruction of portal vein branches. It has been revealed
that the ligation of the common bile duct alone induces a certain amount of hepatocyte proliferation. It was striking that
external biliary drainage suppressed regeneration capacity in cholestatic rat liver after partial hepatectomy. The strong
regeneration in nonligated lobes induced by portal branch ligation was similar to the liver regeneration seen after partial
hepatectomy with respect to the induction of DNA polymerases. Taken together, the aspects of DNA replication, particularly
the induction of DNA polymerases, may contribute to shedding new light on the regeneration of human liver.
This work was supported in part by a Grant-in-Aid for General Scientific Research and for Cancer Research from the Ministry
of Education, Science and Culture, Japan, and by grants from the Uehara Memorial Foundation 相似文献
152.
Satoshi Abe 《Journal of orthopaedic science》1997,2(2):75-83
The purpose of this study was to validate the hypothesis of neural histogenesis of Ewing's sarcoma of bone and related tumors
by light microscopic, electron microscopic, and immunohistochemical analysis. We studied 32 round-cell sarcomas (19 cases
of Ewing's sarcoma of bone, 3 extraskeletal Ewing's sarcomas, 5 peripheral primitive neuroectodermal tumors (PNET) and 5 cases
of unclassified small round-cell type of neurogenic sarcoma (NS). Immunoreactivity for MIC2 was observed in all cases of Ewing's
sarcoma and PNET, and in 1 cases of NS. Positive immunoreactivity for neural markers (NSE, synaptophysin, S-100) was found
frequently in some tumors. Ultrastructurally, some specific features of neural differentiation, such as a fragmented basal
lamina and neurosecretory granule-like particles, were found even in typical cases of Ewing's sarcoma of bone, which presented
without a rosette arrangement and were almost negative for neural immuno-markers, but positive for MIC2. These ultrastructural
neural features were observed less frequently in Ewing's sarcoma of bone than in PNET and NS. However, no significant correlation
was demonstrated between the immunoreactivity for neural markers and the ultrastructural and histological neural features.
These results support the hypothesis of a neural origin of Ewing's sarcoma and related neoplasms, and suggest that some overlapping
entity could persist in PNET and Ewing's sarcoma and that this entity could be seen in histological and immunohistochemical
studies of both tumors. 相似文献
153.
Cytomegalovirus (CMV) is regarded as a predominant infectious agent in solid organ transplants. CMV disease has highly protean
clinical manifestations. Nevertheless, urinary tract involvement seems to be very rare during CMV infection. We report two
cases of renal transplant recipients in whom ureteral stricture developed in the course of CMV disease. Histologic data were
available for them and were consistent with CMV infection. We discuss previous case reports and propose physiopathologic mechanisms.
Received: 3 October 1996 Received after revision: 13 February 1997 Accepted: 17 February 1997 相似文献
154.
胃癌病人天然杀伤细胞活性监测 总被引:2,自引:0,他引:2
报道微量细胞毒试验——LDH 释放法用于对胃癌病人临床免疫的监测.测定100例正常人和50例胃癌病人外周血 NK 细胞毒.结果:正常人值为36.10±5.68,胃癌组中,10例早期胃癌为28.76±4.70,25例进展期胃癌为14.51±5.80,15例晚期胃癌为11.86±4.43,与正常人值比较,P 值分别>0.05,<0.01和<0.01.NK 细胞毒活性随胃癌病变的进展和肿瘤体积的增大而逐渐降低,手术切除肿瘤后可有不同程度回升,甚至恢复到正常水平。长期化疗能损伤 NK 活性. 相似文献
155.
目的:探讨人卵巢癌标本中,肿瘤转移抑制基因nm23-H1编码蛋白NDPK-A表达的临床意义及其与预后的关系。方法:应用免疫组织化学抗生蛋白链菌素-过氧化酶结合(S-P)法,检测58例人卵巢癌标本中nm23-H1蛋白水平。结果:nm23-H1蛋白的表达与患者手术时是否有淋巴结及大网膜转移相关(P〈0.05),但原发灶与转移灶间的阳性表达率相差不显著;与患者术后生存时间密切相关(P〈0.01),术后生 相似文献
156.
David L. Mattson Shanhong Lu Allen W Cowley Jr 《Clinical and experimental pharmacology & physiology》1997,24(8):587-590
1. Nitric oxide (NO) has been implicated as an important controller in the short- and long-term regulation of arterial pressure. Studies performed in our laboratory have demonstrated that chronic intravenous administration of the NO synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) selectively decreases renal medullary blood flow, causes sodium and water retention and leads to hypertension. 2. To determine the importance of the renal medullary effects in this model of hypertension, further studies were conducted to examine the influence of selective stimulation or inhibition of renal medullary NO on whole kidney function and cardiovascular homeostasis. With the use of a unique catheter to directly infuse into the renal medullary interstitial space, stimulation (bradykinin or acetylcholine) or inhibition (L-NAME) of renal medullary NO selectively increased or decreased renal medullary blood flow. 3. The changes in medullary flow in these experiments were associated with parallel changes in sodium and water excretion independent of alterations in renal cortical blood flow or glomerular filtration rate. 4. Studies were then undertaken to examine the long-term effects of selective NO inhibition in the renal medulla on cardiovascular homeostasis. Chronic infusion of L-NAME directly into the renal medullary interstitial space of uninephrectomized Sprague-Dawley rats led to a selective decrease in renal medullary blood flow that was sustained throughout the 5 day L-NAME infusion period. The decrease in medullary blood flow was associated with retention of sodium and the development of hypertension and the effects were reversible. 5. The data reviewed indicate that NO in the renal medulla has a powerful influence on fluid and electrolyte homeostasis and the control of blood pressure. 相似文献
157.
Summary A study of the association between the rate of proliferation of marrow fibroblast-like stromal cells (in vitro) and the rate of endosteal bone mineralization (EsMR) (in vivo) was undertaken in an osteopenic rat model. We report than 200 g male rats treated with cortisone acetate (5 mg/day for 7
days) exhibit decreases in marrow fibroblast colony-forming units (FCFU) and tetracycline-based measurements of EsMR at the
level of the femoral midshaft. In cortisone-treated rats recovering for 1–3 weeks, the FCFU census and EsMR normalized during
the first posttreatment week, remained at control levels after 2–3 weeks, and exhibited a relapse in the third week which
signified only partial recovery. These changes were unrelated to patterns of body weight gain. The data indicate that the
FCFU census can serve to index endosteal osteoblast vigor. 相似文献
158.
Maria Cristina Locatelli Lucilla Tedeschi Maurizia Clerici Antonella Romanelli Adelaide D'Antona Roberto Labianca Gino Luporini 《Supportive care in cancer》1996,4(3):218-219
We have reviewed the incidence of cisplatin-induced anaemia in patients affected with solid tumours treated with at least three courses of first-line cisplatincontaining regimens. In our experience, a low percentage (5%) of patients required transfusions of red blood cells. We think it is of the utmost importance to adopt uniform criteria in monitoring and treatment of patients at risk of developing cisplatin anaemia and to identify subsets of patients to eventually treat with erythropoietin. 相似文献
159.
补肾中药对雄激素致不孕大鼠卵巢核仁组成区蛋白的影响 总被引:4,自引:0,他引:4
观察补肾中药对雄激素致不孕大鼠卵巢核仁组成区蛋白的影响。用SD雌性大鼠幼仔,出生9d龄注射丙酸睾丸酮,制成雄激素致不孕大鼠(ASR)模型。80d龄灌服补肾中药水溶液两周。100d龄心脏灌注处死。以核仁组成区蛋白嗜银染色(AgNOR)和增殖细胞核杭原(PcNA)为指标,观察卵巢颗粒细胞、间质腺细胞的形态学变化。结果:补肾中药能够使ASR卵巢颗粒细胞增殖、卵泡发育。治疗组的AgNOR和PcNA计数明显高于模型组,而与对照组之间无显著差异。结论:补肾中药的这种作用可能是通过调节了下丘脑-垂体-卵巢性腺功能的结果,从而促使卵巢颗粒细胞发育、卵泡成熟。 相似文献
160.
Satomi Kitagawa Yu Yamaguchi Emiko Sameshima Masaru Kunitomo 《Clinical and experimental pharmacology & physiology》1994,21(12):963-970
1. Endothelium-dependent relaxation in response to acetylcholine (ACh) and the calcium ionophore A 23187 was examined in aorta, coronary, basilar and renal arteries isolated from Watanabe heritable hyperlipidaemic (WHHL) rabbits of 2, 6 and 12 months of age, with normolipidaemic heterozygous WHHL rabbits as controls. 2. In the rings of WHHL rabbit aortae and coronary arteries preconstricted with vasoconstrictors, endothelium-dependent relaxation in response to ACh was attenuated with age compared to the heterozygous WHHL rabbits. A significant negative correlation was found between the total cholesterol content and the relaxation response to ACh in the aortae or coronary arteries from 6 and 12 month old WHHL rabbits. 3. In the rings of basilar arteries, endothelium-dependent relaxations to ACh were not modified with age. Similarly, in the rings of renal arteries, the relaxation response to ACh was not changed with age, but in the 6 and 12 month preparations, after the age of 6 months, a contraction following the relaxation appeared at higher concentrations of ACh (10?7 to 10?6 mol/L). The contraction was endothelium-dependent and inhibited by indomethacin. 4. A 23187-induced endothelium-dependent relaxations were also markedly attenuated in the aorta and significantly in the coronary artery with age. 5. Endothelium-independent relaxation to sodium nitroprusside was not changed in all arteries from WHHL rabbits of different ages. 6. These findings indicate that in the aorta and coronary artery of the WHHL rabbit, the endothelium-dependent relaxation to ACh and A 23187 becomes impaired with increasing age (i.e., with the progression of cholesterol deposition in the arterial wall) but is preserved in the basilar and renal artery. 相似文献