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111.
AIM:To determine the relationship between ischemia, hypoxia and the production of vascular endothelial growth factor in rat myocardium and its basic mechanism. METHODS:(1) 28 Wistar rats were randomly divided into 4 groups: group A, normal control;group B, 1 day's acute myocardial infarction;group C, 3 day's acute myocardial infarction;group D, 7 day's acute myocardial infarction. (2) Rat cardiac myocytes cultured were primarily divided into some groups, hypoxia incubated 24 hours; PMA groups, hypoxia incubated 24 hours with PKC activator (PMA), A 0 ng/mL; B 10 ng/mL; C 100 ng/mL; D 1 000 ng/mL; Chelerythrine groups, hypoxia incubated 24 hours with PKC inhibitor (chelerythrine), A 0 nmol/L; B 10 nmol/L. (3) By computer scanned and quantitated, vascular endothelial growth factor (VEGF) protein was detected with immunohistochemical technique. RESULTS:The longer time of ischemia and hypoxia was, the higher the VEGF production.The relat ionship was found between the time of ischemia or hypoxia and the production of VEGF.The product ion of VEGF protein was further promoted by PMA with different concentrat ion, decreased by chelerythrine.CONCLUSION: Ischemia or hypoxia strongly stimulated the production of VEGF in myocardium, which played an important role in autoprotecting of ischemic or hypoxic myocardium. Hypoxia-induced PKC activation is one kind of basic mechanisms in this course. 相似文献
112.
AIM:To observe pathomorphological changes in cerebral cortex and hippocampus in the mouse with synthetic vascular dementia.METHODS:The synthetic vascular dementia model was produced in the mouse. Animals were killed 7 d, 15 d, and 30 d after the operation, brain tissues were removed and embedded in paraffin. Section of 8μm thickness were stained with hematoxylin-eosin(HE)and Nissl methods, and observed with light microscope.RESULTS:The cerebral cortex in the mouse became thinner on the seventh day, karyopyknosis in partial nervous cells was formed, the number of local neurons was reduced, sieve structure was observed, and glial cells pro liferated, with the similar results 15 d and 30 d afteroperation.Model mouseπs hippocampal cells in CA1 area were reduced and almost disappeared 30 d after operation.At the same time, glial cells were abundantly proliferated, tu bercles were formed.Cells in CA2, CA3 area were also reduced and hippocampal sclerosis occurred.CONCLUSION:Delayed necrosis of hippocampal pyramidal cells may be the pathological basis of ischemia cerebral vascular dementia. 相似文献
113.
Hiro HORIKIRIZONO Kumiko ISHIGAKI Keigo IIZUKA Kei TAMURA Naoki SAKURAI Kazuyuki TERAI Tatsuya HEISHIMA Orie YOSHIDA Kazushi ASANO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(5):720
Angiogenesis plays an important role in the proliferation and metastasis mechanisms of malignant tumors. Vascular endothelial growth factor (VEGF), a group of cytokines that contribute to angiogenesis and vasculogenesis. This study aimed to investigate the serum VEGF-A concentrations in dogs with various proliferative diseases. A total of 202 dogs that were histopathologically diagnosed with proliferative diseases were included in the study. Serum VEGF-A concentrations were measured using enzyme-linked immunosorbent assay. Median serum VEGF-A concentrations in dogs were as follows: healthy dogs, 4 pg/ml [0–21 pg/ml]; hepatocellular carcinoma, 30 pg/ml [0–158 pg/ml, P=<0.001]; hepatocellular adenoma, 32 pg/ml [0–49 pg/ml, P=0.003]; hepatic nodular hyperplasia, 18 pg/ml [0–51 pg/ml, P=0.595]; adrenal pheochromocytoma, 32 pg/ml [0–187 pg/ml, P=<0.001]; adrenocortical carcinoma, 32 pg/ml [3–161 pg/ml, P=0.002]; adrenocortical adenoma, 27 pg/ml [0–106 pg/ml, P=0.005]; colorectal adenocarcinoma, 36 pg/ml [0–75 pg/ml, P=0.002]; colorectal adenoma, 43 pg/ml [0–48 pg/ml, P=0.144]; inflammatory colorectal polyps, 37 pg/ml [0–111 pg/ml, P=<0.001]; pulmonary adenocarcinoma, 35 pg/ml [4–107 pg/ml, P=0.002]; pulmonary histiocytic sarcoma, 35 pg/ml [0–131 pg/ml, P=0.016]; and follicular thyroid carcinoma, 35 pg/ml [0–106 pg/ml, P=0.009]. The serum VEGF-A concentrations were significantly higher in dogs with neoplastic lesions compared to healthy dogs, except for colorectal adenoma. High serum VEGF-A concentrations were observed in dogs with proliferative diseases. The present study suggests that angiogenesis-inhibiting therapy, which targets VEGF-A, may be useful for canine neoplastic diseases. 相似文献
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AIM: To investigate the relationship between hemin and Erk1/2 activation in human umbilical vascular endothelial cells (HUVECs). METHODS: Cultured HUVECs were separately incubated with hemin or H2O2 for different times. Subsequently Erk1/2 phosphorylation and total Erk1/2 were determined by Western blotting assay. Flow cytometry was employed to determine the cell cycle distribution. RESULTS: Hemin at the concentration of 1-10 μmol/L induced the phosphorylation of Erk1/2 in HUVECs, and sustained the phosphorylation of Erk1/2 for three hours. The duration of phospho-Erk1/2 induced by hemin was much longer than that in H2O2 control (3 h vs 30 min). CONCLUSION: Hemin induces and sustains the phosphorylation of Erk1/2 in HUVECs, which indicates that the effect of hemin on the Erk1/2 activation may be one of pharmacological target of hemin. 相似文献
118.
XING Li-ying ZHENG Ling-yun WU Yu-e ZENG Cui-ling GUI Ya-li FANG Hai-yan WU Teng WANG Li-jing LI Wei-dong 《园艺学报》2014,30(11):1987-1992
AIM: To observe the pathological characteristics of the thoracic aorta in the p110δ-mutant mice.METHODS: The thoracic aorta of wild type male mice and p110δ-deficient male mice (8 weeks old) were achieved. HE, IHC and IF staining were performed on the paraffin fixed arterial sections. The mRNA expression was detected by real-time PCR.RESULTS: The vascular wall became thinner and the vessel diameter enlarged after inactivating mutation of p110δ. After inactivating mutation of p110δ, the smooth muscle cells showed vacuolar degeneration, morphological disorders and elastic fiber local fracture. The collagen content was reduced after inactivating mutation of p110δ. The expression of matrix metalloproteinase-3 (MMP-3) and MMP-9 was up-regulated after inactivating mutation of p110δ.CONCLUSION: Inactivating mutation of p110δ may contribute to the injury of artery vascular wall by up-regulation of MMPs. 相似文献
119.
谭凤梧 《沈阳农业大学学报》1989,(3)
本试验以玉米沈农171×33O单交种及其亲本沈农171自交系为试材,通过1987~1988年的试验,测定了不同采收期玉米笋产量、质量、笋支长棍等指标。试验结果表明:单交种及自交系最佳采收期各不相同,沈农171×330单交种玉米笋最佳采收期为吐丝后第2天,沈农171自交系为吐丝后第1天。 相似文献
120.
Steven A. Ringold DVM Efrat Kelmer DVM DACVECC 《Journal of Veterinary Emergency and Critical Care》2008,18(3):306-311
Objective: To demonstrate that ultrasound‐guided femoral artery catheterization is feasible and practical in dogs. Case series summary: Four female mixed breed dogs weighing 14–23 kg were used following a terminal junior surgery laboratory and had been anesthetized before the ultrasound study. Dogs were positioned in lateral recumbency with the upper limb abducted and immobilized. The dependent limb was extended and shaved and isopropyl alcohol was applied. An ultrasound transducer was oriented transverse to the axis of the limb and, following ultrasonographic identification, the femoral artery was cannulated and a catheter was placed using the Seldinger technique. Ultrasound‐guided catheterization was successful in 9 of 10 attempts; cannulization was successful in 10 of 10 attempts. Procedure time improved from 10 minutes to 1 minute during practice. Each of the 2 investigators was able to simultaneously ultrasound and cannulate the vessel. The major complication was hematoma formation, which occurred regardless of success. Information provided: Ultrasound‐guided femoral artery catheterization is feasible and relatively easy to master in medium‐size, anesthetized dogs. 相似文献