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51.
Jung Han Kim Sang Jun Lee Young Bok Han Jung Jo Moon Jong Bae Kim 《Archives of pharmacal research》1994,17(2):115-118
This paper describes the isolation of isoguanosine from Croton tiglium L. and its cytotoxic effect against several tumor cell lines in culture and newly reports that isoguanosine has an antitumor activity against implanted S-180 ascitic tumor mice. Isoguanosine is effective at the dose of 24 mg/kg/day x 5, with T/C value of 168%. Isoguanosine inhibits the growth of S-180 and Ehrlich solid tumor in mice at the optimal doses of 96 mg/kg/day x 12 and 48 mg/kg/day x 12, with 1-T/C values of 65% and 60%, respectively. 相似文献
52.
53.
Navis G. J.; Dullaart R. P. F.; Vellenga E.; Elema J. D.; de Jong P. E 《Nephrology, dialysis, transplantation》1994,9(10):1477-1481
POEMS syndrome is a multisystem disorder associated with plasmacell dyscrasias. This report describes a patient with POEMS-associatedrenal disease and reviews the literature on biopsy-proven renalinvolvement in POEMS syndrome. Our patient had glomerulonephritiswith membranoproliferative features on light-microscopy withoutcharacteristic findings on immunofluorescence, and with ultra-structural evidence of glomerular microangiopathy. Ultrastructuralevidence of microangiopathy was also found in vasa nervorum.In 20 other cases of POEMS- associated renal disease, 16 hadglomerular disease. Light-microscopy showed membranoproliferative-likeglomerulopathy in 14 patients and glomerular microan giopathyin two. Ultrastructural evidence of microangi opathy was presentin all 15 patients in whom electron- microscopy was done. Thus,in most patients with POEMS-associated glomerular disease acharacteristic lesion is present with evidence of endothelialinjury. As endothelial damage is also found in endoneural vessels,generalized endothelial injury may play a role in non-renalmanifestations of POEMS syndrome. In previous reviews manifestationsof the POEMS syndrome were similar for patients with or withoutmyeloma. Among patients with biopsy-proven glomerular disease,however, myeloma patients are underrepres ented. Whether thisrepresents a sampling error or has true pathophysiological significanceremains to be established. 相似文献
54.
Kyung Bok Lee Jong Sig Kim Sang Tae Kwak Wonbo Sim Jong Hwan Kwak Yeong Shik Kim 《Archives of pharmacal research》1998,21(5):555-558
Chondroitin sulfates were isolated from the mud snail. For the quantitative analysis of enzymatic digestion products of isolated
chondroitin sulfates, strong anion exchange-high performance liquid chromatography (SAX-HPLC) was performed. By the action
of chondroitinase ABC, three unsaturated disaccharides 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-D-galactose (ΔDi-OS), 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-6-O-sulfo-D-galactose (ΔDi-6S) and 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-4-O-sulfo-D-galactose (ΔDi-4S) were produced from the mud snail chondroitin sulfates. The analysis showed that relative proportion
of ΔDi-OS/ΔDi-6S/ΔDi-4S was 58.7/3.1/38.2. The immunomodulating activity of chondroitin sulfate was examined by cell proliferation
assay and these results suggest that it might be a immunosuppressant. 相似文献
55.
56.
J. K. Kang Sang Won Lee Min Woo Baik Byung Chul Son Yong Kil Hong Chul Ku Jung Keon Hee Ryu 《Child's nervous system》1998,14(7):297-301
Accurate assessment and replacement of blood loss and fluid–electrolyte deficit during craniosynostosis repair is difficult
owing to patient size and the diversity of surgical technique. Forty-three patients undergoing primary craniosynostosis repair
over a 10-year period were studied retrospectively to determine blood loss and fluid deficit and to assess blood transfusion
practices during both intraoperative and postoperative periods. Blood loss was calculated on the basis of estimated red cell
mass (ERCM) and fluid-electrolyte imbalance was investigated with blood samplings. Blood transfusion was considered appropriate
if the postoperative or posttransfusion ERCM was within 12% of the preoperative value. Estimated fluid requirement (EFR) was
used in 4 ml kg–1 h–1 except for neonates. Intraoperatively, 80% of all patients were appropriately managed with respect to blood transfusion and
EFR. Postoperatively only 20% of the patients receiving transfusions were transfused appropriately. In 23.3% of these patients
(10/43) unexpected respiratory distress developed immediately after their recovery from the anesthesia. With the measurement
of estimated blood volume and allowable blood loss, appropriate transfusion could be achieved for the successful treatment
of the primary craniosynostosis.
Received: 16 February 1998 相似文献
57.
Y M Chung T S Yeh Y Y Tsai H Chiang J H Liu 《Ophthalmologica. Journal international d'ophtalmologie. International journal of ophthalmology. Zeitschrift für Augenheilkunde》1988,196(3):161-166
Lymphomatoid granulomatosis is an angiocentric and angiodestructive lympho-proliferative disorder involving multisystems but rarely conjunctiva. We present a 62-year-old Chinese female with lymphomatoid granulomatosis who had an ulcerative conjunctival nodule. Conjunctival biopsy revealed pathological findings important for diagnosis and indicating progression of disease severity. To our knowledge, this is the first report to demonstrate pathological findings characteristic of lymphomatoid granulomatosis with conjunctival involvement. 相似文献
58.
Amy C Y Lo Alvin K H Cheung Victor K L Hung Chung-Man Yeung Qing-Yu He Jen-Fu Chiu Stephen S M Chung Sookja K Chung 《Journal of cerebral blood flow and metabolism》2007,27(8):1496-1509
Previously, we reported that transgenic mice overexpressing endothelin-1 in astrocytes showed more severe neurological deficits and increased infarct after transient focal ischemia. In those studies, we also observed increased level of aldose reductase (AR), the first and rate-limiting enzyme of the polyol pathway, which has been implicated in osmotic and oxidative stress. To further understand the involvement of the polyol pathway, the mice with deletion of enzymes in the polyol pathway, AR, and sorbitol dehydrogenase (SD), which is the second enzyme in this pathway, were challenged with similar cerebral ischemic injury. Deletion of AR-protected animals from severe neurological deficits and large infarct, whereas similar protection was not observed in mice with SD deficiency. Most interestingly, AR(-/-) brains showed lowered expression of transferrin and transferrin receptor with less iron deposition and nitrotyrosine accumulation. The protection against oxidative stress in AR(-/-) brain was also associated with less poly(adenosine diphosphate-ribose) polymerase (PARP) and caspase-3 activation. Pharmacological inhibition of AR by Fidarestat also protected animals against cerebral ischemic injury. These findings are the first to show that AR contributes to iron- and transferrin-related oxidative stress associated with cerebral ischemic injury, suggesting that inhibition of AR but not SD may have therapeutic potential against cerebral ischemic injury. 相似文献
59.
Deficiency of insulin receptor substrate-1 impairs skeletal growth through early closure of epiphyseal cartilage. 总被引:5,自引:0,他引:5
Kazuto Hoshi Naoshi Ogata Takashi Shimoaka Yasuo Terauchi Takashi Kadowaki Shin-Ichi Kenmotsu Ung-Il Chung Hedehiro Ozawa Kozo Nakamura Hiroshi Kawaguchi 《Journal of bone and mineral research》2004,19(2):214-223
Morphological analyses in and around the epiphyseal cartilage of mice deficient in insulin receptor substrate-1 (IRS-1) showed IRS-1 signaling to be important for skeletal growth by preventing early closure of the epiphyseal cartilage and maintaining the subsequent bone turnover at the primary spongiosa. Introduction: IRS-1 is an essential molecule for intracellular signaling by IGF-I and insulin, both of which are potent anabolic regulators of cartilage and bone metabolism. To clarify the role of IRS-1 signaling in the skeletal growth, morphological analyses were performed in and around the epiphyseal cartilage of mice deficient in IRS-1 (IRS-1(-/-)), whose limbs and trunk were 20-30% shorter than wildtype (WT) mice. MATERIALS AND METHODS: The epiphyseal cartilage and the primary spongiosa at proximal tibias of homozygous IRS-1(-/-) and WT male littermates were compared using histological, immunohistochemical, enzyme cytohistochemical, ultrastructural, and bone histomorphometrical analyses. RESULTS: In and around the WT epiphyseal cartilage, IRS-1 and insulin-like growth factor (IGF)-1 receptors were widely expressed, whereas IRS-2 was weakly localized in bone cells. Chronological observation revealed that height of the proliferative zone and the size of hypertrophic chondrocytes were decreased in WT mice as a function of age, and these decreases were accelerated in the IRS-1 (-/-) cartilage, whose findings at 12 weeks were similar to those of WT at 24 weeks. In the IRS-1(-/-) cartilage, proliferating chondrocytes with positive proliferating cell nuclear antigen (PCNA) or parathyroid hormone (PTH)/PTH-related peptide (PTHrP) receptor immunostaining had almost disappeared by 12 weeks. Contrarily, TUNEL+ apoptotic cells were increased in the hypertrophic zone, at the bottom of which most of the chondrocytes were surrounded by the calcified matrix, suggesting the closure of the cartilage. In the primary spongiosa, bone volume, alkaline phosphatase (ALP)+ osteoblasts, TRACP+ osteoclasts, and the osteopontin-positive cement line were markedly decreased. Bone histomorphometrical parameters for both bone formation and resorption were significantly lower in IRS-1(-/-) mice, indicating the suppression of bone turnover. CONCLUSION: The IRS-1(-/-) epiphyseal cartilage exhibited insufficient proliferation of chondrocytes, calcification of hypertrophic chondrocytes, acceleration of apoptosis, and early closure of the growth plate. Thus, the data strongly suggest that IRS-1 signaling is important for the skeletal growth by preventing early closure of the epiphyseal cartilage and by maintaining the subsequent bone turnover at the primary spongiosa. 相似文献
60.