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11.
To elucidate the mechanisms by which thiamine deficiency affects hepatic microsomal monooxygenase activities, the effect of thiamine deficiency on two constitutive cytochrome P450 isozymes, P450IIE1 and P450IIC11, was investigated, using weanling male Sprague-Dawley rats. The clinical signs of thiamine deficiency were apparent after feeding a thiamine-deficient diet for 3 weeks. Thiamine deficiency caused an increase in P450IIE1, which was determined by N-nitrosodimethylamine demethylase assay and immunoquantitation of P450IIE1. This increase in the P450IIE1 level was mainly attributed to thiamine deficiency per se but not to dietary restriction. Ketone bodies were not elevated in thiamine-deficient rats, whereas ketone bodies were elevated and may have served as inducing factors in calorically restricted pair-fed animals. Injections of pyruvate or pyrithiamine in addition to thiamine deficiency did not potentiate the induction effect. On the other hand, thiamine deficiency did not affect the level of P450IIC11 during the 3 weeks of feeding the thiamine-deficient diet. In addition, thiamine deficiency increased cytosolic glutathione S-transferase activity but not steroid isomerase activity. The present study demonstrates the specificity of thiamine deficiency per se in the induction of P450IIE1 which does not involve an increase in the ketone body level. 相似文献
12.
Ischemic necrosis of the entire femoral head and rapidly destructive hip disease: potential causative relationship 总被引:6,自引:0,他引:6
Kyung Nam Ryu Eui Jong Kim Myung Chul Yoo Yong Koo Park David J. Sartoris Donald Resnick 《Skeletal radiology》1997,26(3):143-149
Objective. Rapidly destructive hip disease (RDHD) is an uncommon disorder of the hip that has been considered a disease of unknown cause
and distinct from ischemic necrosis of the femoral head. The objective of this study was to investigate ischemic necrosis
of the femoral head as one potential cause of RDHD. Design and patients. In 600 patients who underwent MR imaging of the hip, 20 cases of ischemic necrosis involving the entire femoral head in 18
patients (3%) were retrospectively studied with routine radiography and MR imaging. All patients had surgically confirmed
ischemic necrosis of the femoral head. Results and conclusions. All patients showed rapid destruction of the femoral head on routine radiography and MR imaging as compared with the gradual
onset of clinical symptoms. Plain radiographs showed several bone fragments at the inferomedial aspect of the femoral head
(75%), acetabular erosions (55%), eccentric depression at the lateral articular surface of the femoral head conforming to
the adjacent acetabulum (35%), and mild osteoarthritis (15%). Bone sclerosis was often present at sites of impaction between
the femoral head and the acetabulum. MR imaging showed marked distention of the joint capsule in all cases. In 14 of 20 cases,
the contents of the joint space showed predominantly low or intermediate signal intensity on T1- and T2-weighted images. Ischemic
necrosis involving the entire femoral head may represent one of the causes of RDHD. 相似文献
13.
Arthroscopic all-inside repair techniques of lateral meniscus anterior horn tear: a technical note 总被引:1,自引:0,他引:1
Choon Key Lee Jeung Tak Suh Chong Il Yoo Hyung Lae Cho 《Knee surgery, sports traumatology, arthroscopy》2007,15(11):1335-1339
Although the conventional outside-in technique is especially useful for repairing tears in the anterior portion of the meniscus,
it has a disadvantage of making an additional 1–2 cm sized skin incision and tying knots subcutaneously over the capsule.
Therefore we devised two all-inside repair techniques of lateral meniscus anterior horn tear according to the site of meniscal
tear, meniscosynovial junction or red–red zone. Because these techniques are modified methods of the outside-in meniscal repair
using a spinal needle, they are as simple as conventional outside-in technique. In addition they have advantages of vertical
mattress suture, which is an important characteristic of the all-inside repair, and no additional incision. We recommend these
techniques as an alternative method for repairing an anterior horn tear of the lateral meniscus. 相似文献
14.
15.
J D Lee K H Shin S N Cho J S Shin M G Lee W I Yang C Y Park H S Yoo J T Lee O D Awh 《European journal of nuclear medicine》1992,19(12):1011-1015
Immunoscintigraphy with radiolabelled monoclonal antibodies is widely used to detect solid tumours, but only a few trials have been carried out concerning the specific in vivo localization of an inflammatory process. The purpose of this study was to investigate the detectability of tuberculous foci utilizing this method with radiolabelled bacillus Calmette-Guérin (BCG)-specific F(ab')2 in rabbits. All of the tuberculous lesions (n = 8) were clearly visualized on serial scintigraphy for up to 48 h after injection of the antibody. Immunohistochemical and Ziel-Neelson staining of the tuberculous lesions confirmed the presence of the tuberculous antigens and bacilli. It failed to demonstrate any sustained retention of the BCG-specific antibody fragment in the control group with syphilitic orchitis (n = 2). Therefore, the specific in vivo localization of tuberculosis is feasible by immunoscintigraphy. 相似文献
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18.
进一步研究了抗三尖杉酯碱的HL-60细胞(HR20)抗细胞凋亡的机制及该抗性和抗药性的关系。结果表明,环孢菌素A(CsA)20,10μg·ml ̄(-1)诱导HL-60细胞发生凋亡,而阻断HR20细胞于G_1期,就不能诱导细胞发生凋亡。低浓度的CsA明显增加柔红霉素在HR20细胞内的积聚,其逆转抗药性作用与阻断细胞周期运行无关。CsA10μg·ml ̄(-1)处理HR20细胞,可引起50kDa的蛋白质高度磷酸化。结果提示:环孢菌素A阻断抗三尖杉酯碱的HL-60细胞于G_1期,而诱导敏感的HL-60细胞发生凋亡,其阻断作用与抗药性无关 相似文献
19.
Nae Yu Kim Jung-Soo Pyo Dong-Wook Kang Seung-Min Yoo 《Pathology, research and practice》2019,215(3):580-585
Objective
The aim of this study was to elucidate the clinicopathological significance and prognostic role of loss of claudin-1 in colorectal cancer (CRC).Methods
The correlations between claudin-1 expression and clinicopathological characteristics, including survival rates, were assessed using immunohistochemistry on 260 archival, paraffin-embedded CRC tissues. In addition, the correlations between cludin-1 and nuclear factor-kappa B (NF-κB), epithelial-mesenchymal transition markers and tumor-infiltrating lymphocytes were investigated.Results
Claudin-1 expression was markedly lost in 42.7% of the 260 CRCs analyzed. Loss of claudin-1 expression significantly correlated with larger tumor size, vascular invasion, higher pT stage, and high metastatic lymph node ratio. In addition, loss of claudin-1 expression significantly correlated with NF-κB activation (P?<?0.001), high SNAI (P?<?0.001), and low E-cadherin (P?<?0.001) expressions. Patients with high immunoscores showed significantly lower rates of claudin-1 expression loss (P?=?0.020). In detail, loss of claudin-1 expression were frequently found in CRCs low CD3- and CD8-positive lymphocytes. There were significant correlations between claudin-1 expression loss and poor overall and recurrence-free survivals (P?<?0.001 and P?<?0.001, respectively).Conclusion
Taken together, our results suggest that the loss of claudin-1 expression significantly correlates with aggressive tumor behaviors, high SNAI expression, lower immunoscore, and poor prognoses. 相似文献20.
Inhibition of p38MAP kinase suppresses fibrotic reaction of retinal pigment epithelial cells 总被引:3,自引:0,他引:3