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141.
142.
The efficacy of TKIs in treatment of human primary small cell lung cancer xenograft model in vivo 下载免费PDF全文
Objective: To study the treatmaient of non-small cell lung cancer, we established the HU-Prim allograft transplantation tumor model. Methods: The fresh tumor samples were transplanted in the right scapular subcutaneous layer of the severe combined immunodeficient Non-obese diabetic/severe combined immunodeficient(NOD/SCID) mice. The pathological features of the tumors were observed. Nonnecrotic tissue was inoculated subcutaneously into the right axillary. When the tumor in burdened rat grew approximately 100 mm3, according to the tumor size all the animals were divided into the following four groups, eight rats in each group: solvent control group, gefitinib group(100 mg/kg), erlotinib group(50 mg/kg), afatinib group(20 mg/kg). Aniamals were treated with drugs by intragastric(i.g.) administrated, once daily, for consecutively 14 days. Measure the tumor size 2-3 times every week. Results: Hu Prime1-NSCLC mutant sensitive xenograft model research data showed that reversible tyrosine kinase inhibitors gefitinib, erlotinib and irreversible tyrosine kinase inhibitor afatinib could effectively inhibit tumor growth in EGFR positive NSCLC allografts model. The pharmacodynamic activity of irreversible inhibitor was better than that of the reversible inhibitor. Specimens from clinical anthropogenic tumor retain characteristics of the human primary malignancy, histopathology, biological characteristics, and tumor markers, etc., which can more accurately reflect the characteristics of the tumor and the impact of interventions. Conclusion: The model is not only a good antitumor drug experimental platform, but also a new evaluation tool of individualized medication. 相似文献
143.
Karl H. Summer Dominik Klein Nada de Ruiter Josef Abel 《Biological trace element research》1989,21(1):165-169
In the present study we report on the effects of commonly used nonsteroidal antiinflammatory drugs on metallothionein (MT)
and MT-I mRNA levels. A single dose of chloroquine (100 mg/kg), diclofenac (100 mg/kg), indomethacin (10 mg/kg), or piroxicam
(100 mg/kg) was administered ip to C57B1 mice. After 18 h, MT levels were determined with a Cd-saturation radioassay. MT-I
mRNA levels were measured by Northern Blot analyses using a probe containing the mouse MT-I gene. All drugs tested caused
an increase in the MT content of the liver but not of the kidneys and lung. The lowest and highest effects were observed with
chloroquine (8 times the control value) and diclofenac (18 times), respectively. In accordance with the stimulation of MT
synthesis, increased accumulation of hepatic MT-I mRNA could be demonstrated.
These results indicate that elevated MT levels may contribute to the effectiveness of nonsteroidal antiinflammatory drugs
in the treatment of rheumatoid arthritis (RA). 相似文献
144.
We used a computer-assisted morphometry approach to analyze quantitatively the process of cytoplasmic granule formation in mouse pancreatic acinar cells stimulated with pilocarpine to induce secretion. Our findings suggest that each condensing vacuole/immature granule of pancreatic acinar cells is formed by the progressive aggregation of 106 to 128 unit progranules of narrowly fixed volume, define a range of 7.7 to 9.2 for the factor of volume condensation between the largest immature granules and the mature unit granule, and predict that the formation of a single mature unit granule by the aggregation and fusion of unit progranules involves a net reduction of at least 95% in the amount of membrane surface area associated with these structures. 相似文献
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Luca Caracciolo S. Sakura Minami Takako Niikura Yasuji Matsuoka R. Scott Turner Mark P. Mattson Francesca Bosetti 《Journal of neurochemistry》2013,124(1):59-68
Several epidemiological and preclinical studies suggest that non‐steroidal anti‐inflammatory drugs (NSAIDs), which inhibit cyclooxygenase (COX), reduce the risk of Alzheimer's disease (AD) and can lower β‐amyloid (Aβ) production and inhibit neuroinflammation. However, follow‐up clinical trials, mostly using selective cyclooxygenase (COX)‐2 inhibitors, failed to show any beneficial effect in AD patients with mild to severe cognitive deficits. Recent data indicated that COX‐1, classically viewed as the homeostatic isoform, is localized in microglia and is actively involved in brain injury induced by pro‐inflammatory stimuli including Aβ, lipopolysaccharide, and interleukins. We hypothesized that neuroinflammation is critical for disease progression and selective COX‐1 inhibition, rather than COX‐2 inhibition, can reduce neuroinflammation and AD pathology. Here, we show that treatment of 20‐month‐old triple transgenic AD (3 × Tg‐AD) mice with the COX‐1 selective inhibitor SC‐560 improved spatial learning and memory, and reduced amyloid deposits and tau hyperphosphorylation. SC‐560 also reduced glial activation and brain expression of inflammatory markers in 3 × Tg‐AD mice, and switched the activated microglia phenotype promoting their phagocytic ability. The present findings are the first to demonstrate that selective COX‐1 inhibition reduces neuroinflammation, neuropathology, and improves cognitive function in 3 × Tg‐AD mice. Thus, selective COX‐1 inhibition should be further investigated as a potential therapeutic approach for AD. 相似文献
147.
A phosphorylation system for formation of ATP from AMP by Zymolyase-treated cells of Candida boidinii (Kloeckera sp.) No. 2201 was developed as an ATP production process. This system was shown to be an energy conversion system, from a reduced C1 -compound to ATP through reduction of NAD+ and oxidative phosphorylation but not substrate level phosphorylation, together with phosphorylation of AMP to ADP.Reaction conditions for the ATP production were optimized in respect of substrate and coenzyme concentrations, pH and temperature, osmotic pressure, and oxygen supply. Under the optimal conditions, 26 mM (13 g/liter) and 8.5 dim (4g/liter) of ATP were produced with methanol and formate as C1 -substrate, respectively. 相似文献
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Dr. J. M. Scheiff 《Cell and tissue research》1976,170(3):305-314
Summary Multinucleate epithelial cells occur in the thymus of C3H mice. They are poorly differentiated and scarce, but are more numerous in the medulla than in the cortex. Their increase in number with age is particularly significant between the first and the third months especially for cells with a large number of nuclei, and may be related to thymic involution.Viral particles of type C, similar to those described in murine leukemias, are found in mono- and multinucleate medullary epithelial cells.Research supported by grant 10.013 of the Fonds de la Recherche Fondamentale Collective (Brussels) 相似文献