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71.
A novel naturally occurring antiangiogenic agent isolated from cartilage, referred to as Neovastat (AE-941), was examined for its efficacy against tumor neovascularization and progression. Exposure to Neovastat results in ex ovo antiangiogenic properties in the chorioallantoid membrane of chicken embryo (71% decrease in the angiogenic index as compared to the basic fibroblast growth factor (bFGF) treated control embryos, P < 0.0001). Oral administration of Neovastat inhibits bFGF-induced angiogenesis in the Matrigel mouse model (87.5% decrease in hemoglobin as compared to the bFGF-treated control implants, P < 0.0001). Neovastat also induces a dose response decrease of lung metastases in the Lewis lung carcinoma model (oral administration; 69.1% of inhibition obtained at the maximal dose of 0.5 ml/day, P < 0.0001). Combined with a sub-optimal dose of cisplatinum (2 mg/kg, i.p.), Neovastat (0.5 ml/day) improved the therapeutic index by increasing the antimetastatic efficacy and by exerting a protective activity against cisplatinum-induced body weight loss and myelosuppression. In summary, our experimental data provide evidence of antiangiogenic and antimetastatic properties of Neovastat, following oral administration.  相似文献   
72.
R P Vertes 《Neuroscience》1984,11(3):669-690
The origins of projections within the medial forebrain bundle from the upper brainstem were examined with the horseradish peroxidase technique. Labeled cells were found in approximately 15 upper brainstem nuclei following injections of a conjugate of horseradish peroxidase and wheat germ agglutinin at various levels of the medial forebrain bundle. Labeled nuclei included (from caudal to rostral): dorsal and ventral parabrachial nuclei; Kolliker-Fuse nucleus; dorsolateral tegmental nucleus; A7 (lateral pontine tegmentum medial to lateral lemniscus); median and dorsal raphe nuclei; distinct group of cells oriented mediolaterally in the dorsal pontine tegmentum below the central gray; B9 (ventral midbrain tegmentum dorsal to medial lemniscus); retrorubral nucleus; nucleus of Darkschewitsch, interfascicular nucleus; rostral and caudal linear nuclei; ventral tegmental area; medial part of substantia nigra, pars compacta; and the supramammillary nucleus. With the exception of the ventral parabrachial nucleus, Kolliker-Fuse, A7, B9 and substantia nigra, pars compacta, each of the nuclei mentioned above sent strong projections along the medial forebrain bundle to the rostral forebrain. Sparse labeling was observed throughout the pontine and midbrain reticular formation. With the exception of the dorsal raphe nucleus, projections to the most anterior regions of the medial forebrain bundle (level of the anterior commissure) essentially only arose from presumed dopamine-containing nuclei-retrorubral nucleus (A8 area), interfascicular nucleus, rostral and caudal linear nuclei, substantia nigra pars compacta, and ventral tegmental area. Evidence was reviewed indicating that major forebrain sites of termination for these dopaminergic nuclei are structures that have been collectively referred to as the 'ventral striatum'. It is concluded from the present findings that several pontine and mesencephalic cell groups are in a position to exert a strong, direct effect on structures in the anterior forebrain and that the medial forebrain bundle is the main communication route between the upper brainstem and the forebrain.  相似文献   
73.
Au LC  Lin ST  Peng HJ  Liang CC  Lee SS  Liao CD  Chang ZN 《Allergy》2002,57(3):215-220
BACKGROUND: Cyn d 1, the major allergen of Bermuda grass pollen, contains some acidic/basic isoforms. The N-terminal amino acid sequences of some acidic Cyn d 1 isoforms were found to be different from those of Cyn d 1 cDNA clones identified previously. METHODS: A predicted 17-meric oligonucleotide probe was designed to fish the unidentified isoallergen cDNAs out of BGP cDNA library. The reactive clones were isolated and verified by sequencing. Two of them were expressed in the yeast Pichia pastoris to obtain recombinant Cyn d 1 proteins. RESULTS: All four cDNA clones encode the full-length Cyn d 1 with mature proteins of 244 amino acid residues. A 97-99% identity was found among the deduced amino acids of these four clones while an 86% identity was elicited between the four clones and the ones previously identified. The predicted isoelectric focusing (pI) values of the newly identified Cyn d 1s are acidic while pIs of the previously identified Cyn d 1s are basic. The two recombinant acidic Cyn d 1 proteins possess the epitopes recognized by mouse and rabbit polyclonal anti-Cyn d 1 antibodies, and have human IgE-binding capacity as revealed by immunodot assay. CONCLUSIONS: The present study identified full-length cDNAs encoding new isoallergens of Cyn d 1, and separated Cyn d 1 gene into an acidic group and a basic group.  相似文献   
74.
目的:探讨人参银杏复方制剂对缺氧复氧后海马CAI区神经元的保护作用机制。方法:应用低压氧舱仿海拔8000米高空缺氧模型,采用免疫组织化学及免疫荧光方法并结合图像分析等技术,观察预防性应用人参银杏复方制剂对缺氧24h复氧0h、24h时段海马CAI区GABA、Glu表达的影响。结果:缺氧24h复氧卟组海马CAI区GABA免疫反应阳性神经元数量、Glu免疫反应阳性神经元荧光强度分别较常氧对照组减少和减弱,复氧24h后上述变化更加明显。预防性应用人参银杏复方制剂后海马CAI区GABA免疫反应阳性神经元数量在复氧0h和24h时较常氧对照组多,以复氧0h时增加最明显;Glu免疫反应阳性神经元荧光强度在复氧0h、24h时段也较缺氧复氧实验组相应时段增加。结论:人参银杏复方制剂可增加缺氧复氧后海马CAI区GABA表达及防止Glu过度释放,对缺氧复氧性脑损伤具有保护作用。  相似文献   
75.
76.
Preliminary experiments indicated that solutions of aspirin (ASA) in buffered saline, pH 7.35, did not significantly change nasal airways resistance (NAR) when 0.1 ml of solution containing 22.5 mg (or less) per deciliter was sprayed into each nostril. Subsequently it was shown that this quantity of ASA administered intranasally did not significantly change NAR responses 15 min later to intranasal administration of increasing concentrations of histamine, methacholine, or an irritant (NH3 gas). However, the same atopic subjects demonstrated significantly decreased responses to intranasal challenge with short ragweed extract (SRW) after intranasal ASA. In addition, prior oral administration of ASA, Na salicylate, and indomethacin significantly inhibited nasal challenge responses to SRW in sensitive subjects under controlled conditions.  相似文献   
77.
The responses of 148 atopic patients to some 43 different extracts of allergenic pollen were tested by prick tests. The measure of dissimilarity was introduced and calculated for all pairs of allergens. The investigated allergens were clustered into groups, according to their unbiased greatest similarity, by a matrix-structuring method. Results indicate that subgroups of allergens can be distinguished even within groups of closely related pollen allergens that were believed to be fully cross-reactive. A few cases are demonstrated for various varieties of olives, pecans, date palms, and turf grasses and for some wild chenopods and amaranths. The usefulness of the suggested solution for allergy research and for clinical practice is discussed.  相似文献   
78.
In a first approach, Ole e 8, a novel Ca2+-binding protein from olive pollen, was cloned and produced in Escherichia coli. We have obtained the natural form of Ole e 8 (nOle e 8) from the pollen and examined its immunologic equivalence with its recombinant form (rOle e 8). Size exclusion chromatography and a phenyl-Sepharose CL-4B affinity column were used to obtain nOle e 8 from the olive pollen. Inhibition assays by immunoblotting, using rOle e 8-specific rabbit antiserum, were performed to analyze the immunologic equivalence between the natural and the recombinant allergen, as well as to detect its presence in other pollens. Recombinant and natural Ole e 8 resulted immunologically equivalents, since they completely inhibited the IgG binding of the polyclonal antiserum to each other. Ole e 8-like proteins were detected in Oleaceae and Juniperus communis pollen, and might contribute to cross-reactivity processes between taxonomically related pollens.  相似文献   
79.
目的 :探讨抑郁症脑损伤的机制 ,研究银杏叶提取物 (EGb)及合成抗抑郁药盐酸文拉法辛(Venlafaxine)对抑郁大鼠的抗脑损伤及神经元保护作用。方法 :慢性应激建立大鼠抑郁模型。将 84只雄性大鼠分为正常对照组、抑郁模型组和不同治疗组。快速断头法处死 ,取海马后一侧进行免疫组化反应 ,观察海马CA3区nNOS蛋白的表达 ;另一侧检测NO含量 ;同时测定血清中NO含量。结果 :抑郁模型组海马nNOS表达增加 ,海马及血清中NO含量增加 ,P <0 0 1;联合用药组海马nNOS表达下降 ,海马及血清中NO含量减少 ,P <0 0 1。结论 :慢性应激增加海马nNOS表达 ;EGb有减轻神经元损伤 ,保护神经元的作用 ,其与Venlafaxine合用可能会达到对抑郁进行多靶点、多层次的治疗 ,弥补单一用药的不足。  相似文献   
80.
Rabbit retinal Müller cells were isolated by means of papaine and mechanical dissociation. These cells were shown to have a well preserved morphology and to preserve viability for many hours. Intense wheat germ agglutinin binding occurs on the photoreceptor side of Müller cells, especially in the microvillous region. Rabbit retinal Müller cells have a Na+,K+-activated adenosine triphosphatase activity in the same order of magnitude as brain astroglial cells.  相似文献   
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