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121.
Expression and distribution of vascular endothelial growth factor protein in human brain tumors 总被引:9,自引:0,他引:9
T. Pietsch Markus M. Valter Helmut K. Wolf A. von Deimling H.-J. Su Huang Webster K. Cavenee Otmar D. Wiestler 《Acta neuropathologica》1997,93(2):109-117
Marked neovascularization is a hallmark of many neoplasms in the nervous system. Recent reports indicate that the endothelial
mitogen vascular endothelial growth factor (VEGF) may play a critical role in the regulation of vascular endothelial proliferation
in malignant gliomas. Using novel monoclonal antibodies to the VEGF polypeptide we have determined the expression and cellular
distribution of VEGF protein in a representative series of 171 human central nervous system (CNS) tumors by immunohistochemistry
and immunoblotting. In agreement with previous in situ hybridization data, 19 out of 20 glioblastomas (95%) showed immunoreactivity
for VEGF, whereas both the percentage of immunoreactive tumors and the extent of immunoreactivity for VEGF were significantly
lower in astrocytomas. Of the pilocytic astrocytomas (WHO grade I) 44% were immunoreactive for VEGF, but we observed several
cases with pronounced vascular proliferates in the absence of VEGF. In ependymomas, meningiomas, hemangioblastomas, and primitive
neuroectodermal tumors, there was no correlation between VEGF expression, vascular endothelial proliferation and the grade
of malignancy. Oligodendrogliomas and the oligodendroglial component of mixed gliomas lacked immunoreactive VEGF, indicating
that endothelial growth factors other than VEGF may regulate tumor angiogenesis in these neoplasms. Western blot analysis
showed a predominant VEGF protein species of 23 kDa and confirmed the immunohistochemical data in all cases. Our findings
demonstrate that VEGF is expressed in a wide spectrum of brain tumors in which it may induce neovascularization. However,
other angiogenic factors also appear to contribute to the vascularization of CNS neoplasms.
Received: 18 April 1996 / Revised, accepted: 20 August 1996 相似文献
122.
Comparison of photocoagulation with the argon, krypton, and diode laser indirect ophthalmoscopes in rabbit eyes. 总被引:7,自引:0,他引:7
PURPOSE: The purpose of this study is to compare photocoagulation with the argon green, krypton red, and diode infrared laser indirect ophthalmoscopes in an experimental setting. METHODS: Photocoagulation was performed with each of the laser indirect ophthalmoscopes in a grid pattern within one sector of the same eye of 14 Dutch-belted rabbits. Treatment was performed either with or without scleral depression. Measurements of the retinal burn diameters were performed after hemisecting the globes, and the burns were examined with light microscopy. RESULTS: Variation in burn intensity and diameter (10% to 28%) was common with all 3 laser indirect ophthalmoscopes. Five times more output energy was required to make equivalent burns with the diode laser indirect ophthalmoscope than with the argon or krypton laser indirect ophthalmoscopes. Choriovitreal hemorrhages only occurred during scleral depression. Histopathologically, the argon green laser indirect ophthalmoscope burns spared the choroid and inner sclera, while the intense krypton and diode burns had full-thickness choroidal involvement and even thermal injury to the inner sclera. Scleral depression reduced the mean energy required to create equivalent burns with all three laser indirect ophthalmoscopes. There was a 10% to 40% reduction in the mean retinal burn diameter with scleral depression (argon green, P < 0.0005; krypton red, P < 0.0005; and diode, P < 0.025). CONCLUSION: Photocoagulation with the argon green, krypton red, or diode infrared laser indirect ophthalmoscopes is a safe and effective method of retinal ablation. Decreasing the posterior nodal distance of the eye with scleral depression will produce a smaller spot on the retina with the laser indirect ophthalmoscope. 相似文献
123.
缺氧缺血性脑病新生鼠胃壁内一氧化氮的改变 总被引:12,自引:1,他引:11
目的探讨缺氧缺血性脑病新生鼠胃壁局部一氧化氮(NO)的改变及窒息对消化系统的影响。方法采用二氢硫辛酰胺脱氢酶NADPH组织化学方法,检测24只正常或缺氧新生鼠胃壁各层一氧化氮合成酶(NOS)的分布变化。结果急性缺氧组与正常对照组相比,NOS阳性产物无论在分布、染色深浅、纤维密度及NOS阳性胞体数目上,差异均无显著意义(P>0.05)。但在缺氧缺血性脑病组,其肌层的NOS阳性纤维无论是密度还是染色深浅,均明显强于正常对照组,NOS阳性胞体亦明显多于正常对照组,其差异有非常显著意义(P<0.01);而粘膜和粘膜下层的NOS分布与正常对照组相比,差异无显著意义(P>0.05)。结论窒息时胃动力降低及胃粘膜病变与一氧化氮在胃壁内的改变有关 相似文献
124.
For a period of six months, we collected 12 cases of nocturnal asthmatics (7 males, 5 females); their ages ranged from 20 to 66 (the average age is 49). We found that administration of Uniphyllin (10 mg/kg) once a day at 6 PM could maintain the blood level of theophylline within therapeutic range at least 12 to 24 hrs. The peak expiratory flow rate of the 6 cases we collected, were significantly improved. The result of pharmokinetic parameters: 1) The average of a single dose (12 cases) is AUC (ug. hr/ml) 275.1 +/- 62. k; Kel (hr-1) 0.068 +/- 0.019; Ka (hr-1) 0.33 +/- 0.07); Tmax (hr) 6.3 +/- 1.4; T 1/2 (hr) 11.2 +/- 4.4; Clearance/F (ml/kg/hr) 37.9 +/- 9.0.2). The average of steady state (12 cases) is Css (mg/L) 5. 7 +/- 2.6; Cmax-Cmin (mg/L) 10.09 +/- 1.46.3). The average of relative bioavailability (3 cases) is 82%, 83%, 102%. However, the extent of absorption data is available for only 3 subjects. There are too few subjects to draw any meaningful conclusions about this relative bioavailability. Four cases show slight symptoms, including 1 case of dizziness, 2 cases of nausea, and 1 case gaseousness. It is suggested that the drug be administered at about 6-8 PM to coincide peak levels in the early morning in nocturnal asthmatics. 相似文献
125.
T Huang 《中华心血管病杂志》1991,19(4):231-4, 268
Using the standard 12-lead electrocardiographic QRS scoring system modified by Nancy (1985), 99 ECGs of 52 patients with acute myocardial infarction were used for estimating myocardial infarct size (MIS). One point was designed to represent 3% of the left ventricle. Each patient had the first score of ECG at the day ranged from 7 to 12 and the second 25-32 days post acute chest pain except 5 cases died before the second scoring. The results showed that the averaged score was 6.7 +/- 3.1 points accumulated from all 99 ECGs and 11.0 points from 5 cases died. There was no statistic difference between the points value of the first scoring 6.4 +/- 2.9 vs second 6.5 +/- 2.7 points, nor between the points received from Q waves 4.0 +/- 1.5 vs 3.9 +/- 1.4 points in 47 patients. There was nevertheless strong correlation both between the total points of the first and second scoring, r = 0.85 (P less than 0.0005), and those between the points related to Q wave, r = 0.81 (P less than 0.005). Furthermore, early serial serum CPK changes were determined for evaluating MIS in 25 patients, the results were compared to the first and second scores respectively, the correlations were significant, r = 0.58, P less than 0.0025 and r = 0.47, P less than 0.01.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
126.
The extraction, purification, pharmacological experiments and chemical analysis of anti-hepatoma active principles of Radix Aconiti Kusnezoffii have been studied. The results show that the medicinal material Radix Aconiti Kusnezoffii is efficacious in inhibiting hepatoma, and the active principles are mainly made up of poisonous ester alkaloids. The liver targeting delivery system will be the first choice for its anti-hepatoma preparation, and the effective component AY3a is fit for the preparation of targeted microspheres. 相似文献
127.
128.
129.
Kuan-Pin Su Shih-Yi Huang Chih-Chiang Chiu Winston W Shen 《European neuropsychopharmacology》2003,13(4):267-271
Patients with depression have been extensively reported to be associated with the abnormality of omega-3 polyunsaturated fatty acids (PUFAs), including significantly low eicosapentaenoic acid and docosahexaenoic acid in cell tissue contents (red blood cell membrane, plasma, etc.) and dietary intake. However, more evidence is needed to support its relation. In this study, we conducted an 8-week, double-blind, placebo-controlled trial, comparing omega-3 PUFAs (6.6 g/day) [corrected] with placebo, on the top of the usual treatment, in 28 patients with major depressive disorder. Patients in the omega-3 PUFA group had a significantly decreased score on the 21-item Hamilton Rating Scale for Depression than those in the placebo group (P < 0.001). From the preliminary findings in this study, omega-3 PUFAs could improve the short-term course of illness and were well tolerated in patients with major depressive disorder. 相似文献
130.
Hao Cheng Zhongyao Wu Jianliang Zheng Guilan Lu Jianhua Yan Min Liu Danping Huang Jianxian LinZhongshan Ophthalmic Center Sun Yat-sen University Guangzhou China 《眼科学报》2003,19(1):54-59
Purpose: To study the changes of telomerase activity and cytotoxic effects by Cisplatin; cis-dichlorodiamine platinum (CDDP) in cultured human choroidal melanoma. Material and Methods: The primary cultured human choroidal melanoma cells were cultured in the presence and absence of CDDP with different concentration and time respectively. The toxic effects were evaluated by MTT and the level of telormarse was detected by PCR-ELISA assay. And the relationship between telomerase activity and cytotoxic effects were analyzed by a correlation analysis.Results: Following the increase of the concentration and the time of CDDP, gradually repressed telomerase activity was detected in cultured cells. Meanwhile, the restrain rate of the cells increased. The telomerase activity at 24h and 1μg/ml was repressed significantly compared with the control cells. However, the appearance of cell death lagged behind the decreasing of telomerase.Conclusions: CDDP is an effective telomerase inhibitor in cultured choroidal melan 相似文献